This is a working overview of redox activity, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-08-22. Anything still debated is marked as such rather than presented as settled.
Quality control for GHK-Cu relies on documentation and independent testing rather than a single accepted standard. A certificate of analysis may report peptide purity, copper content, residual solvents, water content, and microbial limits, but the underlying methods and acceptance criteria vary by supplier. Verification can include mass confirmation, amino acid analysis, and comparison with a reference standard when one is available. Open questions include how different copper-binding modes or peptide isomers affect measured activity and whether conventional purity assays capture those differences. Buyers of research-grade material typically need to request raw data rather than rely solely on a summary certificate.
Laboratory characterization of GHK-Cu typically combines separation, spectroscopic, and elemental techniques. Reverse-phase high-performance liquid chromatography is widely used to assess peptide purity, often with ultraviolet detection near the copper-related absorption band or with mass spectrometry for identity confirmation. Because the molecule contains copper, elemental methods such as inductively coupled plasma mass spectrometry or atomic absorption spectroscopy are used to quantify metal content and confirm stoichiometry. No single universal pharmacopeial monograph exists for GHK-Cu. Laboratories therefore validate their own methods, and reported purity values depend on the chosen assay and calibration standards.
Stability of GHK-Cu is influenced by light, oxygen, moisture, pH, and temperature. Solid material is generally kept desiccated and frozen to reduce hydrolysis and oxidation, while aqueous solutions are best prepared fresh or stored cold in aliquots. Repeated freeze-thaw cycles can promote aggregation, precipitation, or peptide degradation. Copper coordination may change under strongly acidic or alkaline conditions, potentially altering the complex's spectroscopic properties. Published long-term stability data for specific matrices, such as cosmetic emulsions or biological buffers, are limited, so shelf-life claims should be treated as formulation-specific rather than universal.
Identity and purity are usually assessed with reversed-phase high-performance liquid chromatography, often paired with mass spectrometry. Copper content is measured separately by techniques such as inductively coupled plasma mass spectrometry or atomic absorption. Amino acid analysis confirms the peptide sequence after hydrolysis. Because the metal and the peptide can be quantified independently, a complete certificate of analysis normally reports both values rather than a single purity figure. This separation of measurements is important when comparing suppliers.
Solid GHK-Cu appears as a blue to blue-violet powder, and the colour is a direct consequence of copper coordination. The complex dissolves readily in water and in many polar solvents, while the free peptide behaves differently. Solubility in nonpolar media is low, which limits its use in oil-based systems. Solutions are typically prepared fresh because the dissolved form is more exposed to hydrolysis and to loss of the metal ion than the dry powder. Working concentrations are usually low, and preparation notes often specify the solvent and the order of addition.
Dry material is typically held at low temperature, often around minus twenty degrees Celsius, and protected from moisture and light. Copper complexes can release their metal ion under acidic conditions or in the presence of competing chelators. Hydrolysis of the peptide backbone is a slower but real pathway, and the histidine residue is susceptible to oxidation over long periods. Stability statements therefore depend on formulation, pH, and container, and they should be read as conditional rather than absolute.
| Property | Value | Notes |
|---|---|---|
| Primary identity method | Reverse-phase HPLC with mass spectrometry | Confirms peptide mass and retention behavior |
| Copper quantification | ICP-MS or atomic absorption spectroscopy | Measures metal content and stoichiometry |
| Spectroscopic feature | Visible absorption from copper(II) d-d transitions | Explains blue to blue-violet color |
| Recommended holding condition | Desiccated, protected from light, stored cold | Reduces hydrolysis, oxidation, and moisture uptake |
| Common purity check | HPLC area percent against a reference standard | Values depend on method and standard choice |
Analytical verification typically combines reversed-phase high-performance liquid chromatography with ultraviolet-visible detection. The copper complex absorbs visible light near 600–630 nm, giving a characteristic blue signal. Mass spectrometry confirms molecular mass and can detect free peptide or mismatched copper stoichiometry. Copper content is often measured independently by inductively coupled plasma mass spectrometry or atomic absorption spectroscopy. Purity, counterion identity, and residual solvents are additional quality-control parameters that methods may address.
Solid GHK-Cu is generally stored as a dry powder under frozen conditions to limit degradation. The peptide bond can hydrolyze, and the copper center can be displaced by strong chelators such as EDTA. Aqueous solutions are less stable than the solid and may lose color or form precipitates over time. Temperature, pH, and oxygen exposure are the main variables that affect shelf life. Neutral to slightly acidic conditions tend to preserve the complex better than strongly alkaline media.
Routine handling calls for minimizing freeze-thaw cycles and preparing solutions shortly before use. Glass or inert plastic containers reduce adsorption and metal leaching. Working stocks are often kept at 2–8 °C for short periods, while long-term reference material stays at −20 °C or below. Light protection is prudent because prolonged exposure may accelerate oxidation of the peptide. Documentation of lot number, concentration, and preparation date supports reproducibility in laboratory work.
Identity and purity are established with a combination of chromatographic and spectroscopic techniques. Reversed-phase high-performance liquid chromatography separates the intact complex from peptide fragments and free copper, and the elution profile yields a purity estimate. Mass spectrometry gives the mass of the intact species and exposes degradation products. Ultraviolet-visible spectroscopy displays a broad absorption band in the visible region that is characteristic of the copper center. Nuclear magnetic resonance is less informative here, because the paramagnetic metal broadens signals and complicates spectral interpretation.
Copper content is measured separately, since a peptide assay alone does not report the metal-to-peptide ratio. Elemental techniques such as inductively coupled plasma optical emission spectroscopy quantify copper after acid digestion of the sample. The result is compared with the theoretical value for a one-to-one complex, and a shortfall indicates free peptide or partial dissociation. Suppliers differ in how they state purity, as some quote peptide content and others quote the whole complex. A defined stoichiometry therefore requires both a peptide assay and a copper assay.
Solid GHK-Cu is usually supplied as a lyophilized powder and is kept cold and dry. Moisture, light, and repeated temperature cycling shorten its useful life in the laboratory. In aqueous solution the complex undergoes slow hydrolysis of the peptide backbone and gradual loss of coordinated copper. Buffers containing strong chelators, such as EDTA, compete for the metal and strip it from the peptide. Working solutions are therefore prepared shortly before use, and leftover liquid is not returned to the stock container.
Aqueous GHK-Cu solutions are less stable than the dry powder. Light, dissolved oxygen and elevated temperature all accelerate loss of the intact complex, and the main observable changes are fading of the blue colour and the appearance of peptide fragments. Acidic conditions protonate the histidine imidazole and weaken copper binding, while strongly alkaline conditions promote hydrolysis of the peptide backbone. Because several degradation routes operate at once, a single shelf-life figure does not describe all storage conditions.
Solid material is typically kept as a lyophilised powder in a sealed, light-protected container at minus 20 degrees Celsius, with desiccant where humidity is high. Working solutions are often prepared fresh, aliquoted and frozen to avoid repeated freeze-thaw cycles. Glassware and buffers are checked for trace metal contamination, since other transition metals can displace copper. Records of lot number, reconstitution date and storage temperature help trace unexpected colour changes. Blue colour itself is not a reliable purity test, because partly degraded solutions can remain visibly coloured.
Copper takes part in redox chemistry, and the same property that makes it useful in enzymes can generate reactive oxygen species when the ion is loosely bound. GHK chelates copper through imidazole, amino, and amide nitrogen donors, which reduces the amount of free copper in solution. Whether that chelation is protective, neutral, or harmful in a given tissue is not settled. Laboratory assays report both antioxidant and pro-oxidant behavior, depending on the conditions and the readout used.
Published work on GHK-Cu is dominated by in vitro experiments and small animal studies. Human trials tend to be short and small, with endpoints such as skin appearance rather than clinical outcomes. Review articles often summarize the same underlying laboratory findings, which can make the evidence base look broader than it is. Several basic questions remain open: the concentration of the intact complex in human tissue, the route by which it crosses the skin barrier, and whether effects seen in culture produce measurable changes in people.
Laboratory studies describe GHK-Cu as a source of copper that cells can take up, with reported effects on collagen, elastin, and glycosaminoglycan synthesis in cultured fibroblasts. The peptide also appears in wound-repair research, where it is linked to the activity of matrix metalloproteinases and their inhibitors. These observations come largely from cell and animal models. How directly the complex controls any single pathway in intact human skin remains an open question, and reported effects depend on concentration, vehicle, and exposure time.
=== COVID-19 === NUVAXOVID is a recombinant subunit vaccine licensed for the prevention of SARS-CoV-2 infection. Market authorization was issued on 20 December 2021. The vaccine contains the SARS-CoV-2 spike protein produced using the baculovirus expression system, which is eventually adjuvanted with the Matrix M adjuvant.
=== Tools for glycoproteins === X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy for complete structural analysis of complex glycans is a difficult and complex field. However, the structure of the binding site of numerous lectins, enzymes and other carbohydrate-binding proteins has revealed a wide variety of the structural basis for glycome function. The purity of test samples have been obtained through chromatography (affinity chromatography etc.) and analytical electrophoresis (PAGE (polyacrylamide electrophoresis), capillary electrophoresis, affinity electrophoresis, etc.).
=== 1988 === 11 February Running to Time, about the new InterCity 225; the National Express Coaches Rapide service; the project team of the Intercity 225, with project director Mike Rollin, and Mike Newman of GEC; the 225 train had to be delivered on 14 February 1988, with an operational life of thirty years; the InterCity 125 was not intended to have been primarily developed - in a board meeting, the commercial directors were not technologically knowledgeable of trains, and asked about alternatives, to be told by an engineering director that a 125 mph diesel train could be developed in two years, so the HST began at that meeting; the British Rail APT-E prototype, powered by the Leyland 2S/350 gas turbine; in 1974 BR commissioned the APT-P, which had ten years of development, due to the active tilting suspension; the 225 train was possibly to enter service on the UK's only large electrified line, the West Coast Main Line, but the much-straighter and faster East Coast Main Line was being electrified, so BR decided to implement the 225 train on the ECML instead; Crewe railway station, which opened in 1837, and where trains were first built nearby in 1843; Steve Corfield, of Crewe Works; the unsprung mass of a train, and Cardan shafts; Roger Ford of Modern Railways; John Prideaux, director of InterCity; David Carter of DCA in Warwick, who designed the livery; the Modernisation Plan was published in December 1954, which had advocated the electrification of the ECML, and the phasing-out of steam travel; the late-1980s ECML electrification had cost BR £350m - it was not government-funded, with 2,800 miles of copper wire, and 33,000 support masts, overseen by Don Heath; all of the improvements in the UK were on old lines of track, but France and Germany had built entire new electrified lines - the TGV was planned from the mid-1960s; G. Freeman Allen of Jane's World Railways; the 225 train underframe being built at Crewe Works; GEC Traction at Preston, Lancashire, Al Reed, the separately excited (Armature Controlled DC Motor) brushed DC electric motor, and Gerald West; the right-angle gearboxes were built by David Brown Ltd and Voith of Heidenheim an der Brenz in southern Germany; Eric Black of Metro-Cammell in Washwood Heath; the ST41 bogies were made by SIG Combibloc Group of Neuhausen am Rheinfall in Switzerland. Narrated by Robin Ellis, produced by Patrick Uden, directed by Paul Fabricius, made by Uden Associates. 12 February Playing with Fire 17 July The Air Fix!, about aviation safety; a television adaptation of a black comedy theatre production by 35-year-old James Castle, dressed as an airline pilot, largely featuring Turkish Airlines Flight 981, the Ermenonville air disaster, in France on 3 March 1974, to this day the worst airliner crash, without any survivors, with 177 British people killed, when a cargo door ruptured, and the subsequent enquiry led to a cover up by the airline and aviation authority; the DC10 had known design failings in its fuselage, and its cargo door design was known to be faulty by the aircraft manufacturer; the American Airlines Flight 96 crash had happened on 12 June 1972, involving a design failure of the cargo door, but the FAA nonetheless gave the DC-10 a certificate of airworthiness; the DC10 had been rushed into service; James Castle accused the aircraft industry of callous negligence; James Castle had been a British Airways aircraft maintenance technician from 1969 to 1977 at Heathrow Airport; he listed the numbers of children that lost one or both parents in the crash, and the numbers of women who were widowed; the theatre production had been going since December 1986, directed by Caroline Noh Narrated by James Castle, produced by Ben Gooder, made by Uden Associates 24 July Nic's Boat, about Nic Bailey, a 37-year-old architect with Foster and Partners; he designed a 40-ft trimaran, called MTC, for the Carlsberg Single-Handed Trans-Atlantic Race on 5 June 1988; he had helped to design the 1978 Sainsbury Centre for Visual Arts in Norwich and the Renault Centre in Swindon; boat builder Spud Rowsell in Exmouth, with Phil Morrison; the hull cost £46,000, and the rigging cost £46,000; the mast and rigging were fitted at Topsham, Devon; Robin Knox-Johnston; French yacht designer Bruno Fehrenbach; he sailed the Atlantic between the Rhumb Line Route and the Great Circle Route; some yachts made the journey to Newport, Rhode Island in ten days; the yacht mast was constructed by Proctor South West. Produced by Michael Wills, directed by Bob Bee, made by Juniper Productions 31 July The Living Dead 7 August Zen and the Art of TV Manufacture, a Panasonic TV factory in South Wales; in 1933 the company founder Kōnosuke Matsushita established seven guiding commercial principles; the Fidelity TV factory in west London was given one year - 1988 - to turn its fortunes around or be closed; the factory's closure was announced to the workforce on 25 January 1988, with the site closing at the end of July 1988; Amstrad bought the Fidelity name in May 1988. Narrated by Alan Howard, directed by Patrick Uden, produced by Michael Proudfoot, made by Uden Associates 14 August How Good Is Soviet Science?, about the political inhibition of Soviet technology in the 1980s; in many ways the Soviet Union in 1987 was a backward and underdeveloped nation, with food queues; the Soviet system didn't respond to changes in demand - everything was planned years in advance; physicist Alexander Prokhorov, who won the Nobel Prize for Physics in 1964; Russians were proud of mathematicians Pafnuty Chebyshev and Nikolai Lobachevsky; large government centrally planned projects were compatible with the communist system, notably its space programme; by the 1970s, the Russians realised that they were some distance behind other countries, such as in disciplines of computing and genetics; science teaching was emphasised at Soviet schools, and English was well taught as well; after secondary schools, half went into science; theoretical science was where Soviet teaching excelled, such as at the Steklov Institute of Mathematics; Yuri Ovchinnikov wanted to improve Soviet science; in the early 1950s, the Soviet Union tried to ignore the findings of genetics, through the work of Trofim Lysenko, who claimed that genetics was anti-communist, known as Lysenkoism leading to many scientists being imprisoned and executed; in the 1960s, a set of large biological research centres were built at Pushchino; one of the most well-built research institutes was the Shemyakin Institute of Bioorganic Chemistry, for biotechnology; Stalin did not like computer science, and it was largely banned until 1958; the Soviets were always years behind in computer science; the first recognisable transistor Soviet computer was the BESM-6 in the 1960s; later computers were the ES EVM series, copied from the IBM System/360; the Akademgorodok (Academic City) in Novosibirsk; the Institute of Automation and Electrometry researched optical memory on holographic slides to and much work on lasers; collaboration between Soviet research and Soviet industry was long-winded, maybe almost impossible - the centrally planned Soviet industry could not sufficiently adapt for short-term changes, as it had to be monotonously planned years in advance, for mass production; Soviet government research was perhaps excellent nonetheless; not many Soviet scientists could travel to international conferences; dissemination of current worldwide science was limited throughout the Soviet Union, due to widespread government restrictions; Suite No. 2 in B minor, BWV 1067. Narrated by US technology historian Loren Graham, produced by Chris Durlacher, directed by Martin Smith, made by Uden Associates, NDR and WGBH. Shown on Nova on 17 November 1987 and 22 March 1988 21 August Toys for the Boys, about the Williams racing team; Graham Hill and Jim Clark in 1967; Tomorrow's World in 1967, narrated by Derek Cooper; journalist Peter Windsor of Williams; aerodynamicist Frank Dernie, head of research at Williams; Keith Botsford, motor racing editor of the Sunday Times; the German racing manager Alfred Neubauer, in the late 1930s; there were 18 F1 teams, with 7 being British; Mobil Oil paid Williams £2.5m for advertising on the cars of Nigel Mansell and Riccardo Patrese; the Williams FW11; racing driver Howden Ganley; part of a BBC Horizon documentary broadcast on 9 March 1981, featuring the Williams FW07, and likewise narrated by Martin Jarvis and produced by Patrick Uden; engineering director Sir Patrick Head; Bach Mass in B minor; Mike Hawthorn, was killed on a public road, the A3 Guildford bypass, in his Jaguar Mark 1 on 22 January 1959; Canadian Gilles Villeneuve was thrown from his Ferrari, when qualifying for the 1982 Belgian Grand Prix; Swedish Ronnie Peterson, died after an accident on the start line at the 1978 Italian Grand Prix; Italian Elio de Angelis was killed in May 1986 at the Circuit Paul Ricard in south-east France; British Piers Courage burned to death at the 1970 Dutch Grand Prix; Jim Clark hit a tree on 7 April 1968 at the 1968 Deutschland Trophäe in the north-west of Baden-Württemberg; German Jochen Rindt was killed at the 1970 Italian Grand Prix after winning the championship in the same year, which was awarded posthumously; Bach Mass in B minor; Frank Williams had a crash on 8 March 1986 in the south of France, with Peter Windsor, in a Ford Sierra, making him quadraplegic; the Williams wind tunnel; Alan Jones waving the British flag at the 1980 Grand Prix; the 1988 season Williams car had a Judd V8 engine; the closing fanfare of Les préludes by Liszt; the documentary ends with German military march Prussia's Glory. Narrated by Martin Jarvis, produced by Patrick Uden, made by Uden Associates 28 August Cold Spring, Morning Sun, about atomic physicist Joan Hinton and her husband Erwin Engst. Joan's mother was teacher Carmelita Hinton. Joan worked on the top secret Manhattan Project at Los Alamos in 1944 which produced the atomic bombs that were dropped on Hiroshima and Hagasaki in the summer of 1945. After the war, Joan, her brother Bill, and her husband Erwin (Sid) Engst travelled to China to join Mao Ze Dong and the cultural revolution. Over the next five decades, Joan and Sid became pioneers in Chinese agricultural science and technology. Narrated by Liza Goddard, written, produced and directed by Chris Haws, Made by InCA. 18 September Taking the Tunnel, who would be travelling through the Channel Tunnel; the tunnel would open in May 1993; Colin Kirkland, technical director of Eurotunnel; Roger Vickerman of the University of Kent; historian Corelli Barnett, and how France and Germany spent money after the war improving rail infrastructure; journalist Kathy Watson; a working model was built of the two Channel rail terminals; 90% of the tunnel went through chalk; the French end was built much more water-tight than the English end, due to the worse geology; the tunnel was around one mile long at the English end, to meet the French side in 1990; the Single Market would stop duty free sales on the Channel ferries; the former Night Ferry across the Channel, which operated until 30 October 1980; TGV Est would connect Bordeaux, and TGV Nord would connect to Germany, the Netherlands, with a spur to the new tunnel; Richard D. North; tolls on the autoroutes discouraged local traffic, which slowed down British motorways; Daniel Ghouzi of Transmanche; Martin Simmons of Kent County Council; A292 junction of M20; Corelli Barnett believed that the British civil service was best at fudging, whereas the French civil service had been trained differently at the French grandes ecoles; a VTG ship from Dover to Dieppe carried trains; freight journeys over 250 miles were most cost effective by rail, but did lack logistical flexibility at either end; Michael Barclay of Tiphook Rail; a distribution centre in Paddock Wood in Kent, built by the Spanish Transfesa; UIC gauge was the main European gauge for freight; Artura Boix of Transfesa; Richard Hope of Railway Gazette; British trains had a 25 tonne axle weight, more than the European 22 tonnes; early plans for the new Eurostar trains, which would be dual voltage for travelling in England and France; rail writer Geoffrey Freeman Allen; the French trains would leave from the Gard du Nord; customs checks would be at the British end in London, but not in France; British Rail planned a high speed line across Kent to open in 1998 from King's Cross, but it would not open until September 2003, and to London in November 2007; Roger Ford of Modern Railways. Narrated by Geoffrey Palmer, produced by Patrick Uden, directed by Paul Fabricius, made by Uden Associates 25 September Road Test about road transport in the UK; there were two million vehicles in the UK in 1930; a test drive would be conducted from The Point, Milton Keynes at 8.30am to Maidstone, by different routes - Mike McDonald of the University of Southampton and Margaret Bell of the University of Nottingham in a Volvo 850 would go across London, and Peter Bonsall and Howard Kirby of the University of Leeds in a Volkswagen Passat B3, would follow the M25 to the north of London, George Hazel of Napier College and John Wootten in a Ford Granada would follow the M25 south of London, and Martin J. H. Mogridge would take the train on the new Thameslink from Bedford railway station via Blackfriars Railway Bridge; the test would be directed from the Road Traffic Research Centre at Middlesex Polytechnic, with Chris Wright, Peter Hills from Newcastle University, and psychologist Ivan Brown from the Applied Psychology Unit (MRC Cognition and Brain Sciences Unit) in Cambridge; variable-message signs (VMS) on the M6; before joining the M25, the vehicles had an average speed of 50 mph; the early plans in the 1940s for the M25, which the M25 to the south and west of London, now largely follows; when the M25 needed to be built, in the 1960s, many environmental objections had arisen for it to be built; Russ Kane in Capital Radio's Flying Eye; David Marsh at the AA Roadwatch studio in north London; the ramp meter, installed on the M6 by John Wootten; all of London's traffic lights were controlled from a computer centre in Westminster, with software (Split Cycle Offset Optimisation Technique) developed by Dennis Robertson; the Volvo 850 enters London along the Edgware Road and Park Lane to Hyde Park Corner; the prototype Autoguide system invented by Ian Catling; automatic vehicle identification (AVI) and piezoelectric strips developed at the University of Nottingham Department of Civil Engineering, and tested by Peter Davies on the Nottingham ring road, next to the QMC; the Volkswagen Passat arrives first at the Great Danes Hotel, making the 107 miles in two hours seventeen minutes, an average speed of 47 mph; the route south of London - 119 miles, also has a 47 mph average speed; the 96-mile rail journey had an average speed of 35 mph; the programme content would be copied by Top Gear fifteen years later. Narrated by Martin Jarvis, produced by David Sharp, directed by Mike Tomlinson, made by Orlando Productions 9 October Look, No Hands! about technology outpacing human knowledge; Hubert Dreyfus of University of California, Berkeley; Martin Corbett, industrial psychologist at the University of Warwick; work by Mike Cooley, and systems design; mechanical engineer Frederick Winslow Taylor and his meticulous improvements to industrial methods, in his book The Principles of Scientific Management; John Harris, manager of the Rolls-Royce helicopter engine plant at Leavesden, Hertfordshire; perhaps automation in engineering manufacturing processes could perhaps add or enhance, rather than totally replace, which required and produced less directly competent workers. Produced by Debra Hauer, directed by Christopher Rawlence, made by Hauer Rawlence Productions 16 October Spytech, John Pike of the Federation of American Scientists and how the Space Shuttle was built mostly for low Earth orbit reconnaissance satellites; but the Titan 34D was also available for many spy satellite launches; Christopher Andrew of the University of Cambridge; Harry Rositzke of the CIA, and the disastrous Operation Red Sox, from 1949 to 1953; William Colby, Director from 1973 to 1976 of the CIA, and how spying methods that worked in Germany during World War II were simply hopeless in a possibly more bizarre culture of communist eastern Europe in the early 1950s, so Ferret missions by B-29 aircraft over the border were attempted instead, but many were shot down; the Americans decided to go for high-altitude reconnaissance; on 1 May 1960, an aircraft photographing a missile construction factory, pilot was sentenced to 10 years, but released after two years in exchange for Rudolf Abel; H. Keith Melton and notorious improvised technology of the KGB; the Russian defector Stanislav Levchenko; the burst transmission method; camera lenses for spy satellites made by Itek; the Space Shuttle was built to maintain and repair the Key Hole set of spy satellites, such as KH-11 KENNEN, launched by the National Reconnaissance Office (NRO) in 1976, and introduced digital photography, and EOSAT and its Landsat program; Jeffrey T. Richelson, a writer on national security; Major-General George Keegan of the Twenty-Fifth Air Force described how the Soviet Union got to know when spy satellites would be overhead, and would hide anything sensitive; listening satellites sent their data to the NSA at Fort Meade in Maryland, such as data from Magnum, launched by the secret STS-51-C mission in January 1985; Paul Bracken and all-source intelligence fusion; Soviet intelligence in the US was quite widespread, with up to 800 spies operating out of Soviet trade missions, and operated much more widespread than the US had attempted; the new KH-12 satellite, that launched in November 1992, could see through clouds. Narrated by Mike Short, produced by Claudia Milne, made by Twenty Twenty 23 October Bamboo, the importance of bamboo to the Chinese economy; Prof Hsiung Wenyue of the Bamboo Research Centre of Nanjing Forestry University; bamboo structures do not collapse in high winds; over a thousand species of bamboo; bamboo dies out for ten years, then grows again; only 15% of China can be cultivated; bamboo can grow four feet in 24 hours, it is the fastest growing plant; bamboo has a tensile strength twice as much as timber; hospitals in China worked with herbal remedies; bamboo traders had quotas set by the Chinese government; bamboo shoots were mostly exported to Japan; growing bamboo helped soil structure; the Chinese government encouraged the growing of bamboo, as an alternative to timber. Narrated by Jenny Agutter, produced by Michael Blakstad, directed by Patrick Fleming, made by Workhouse Productions, made in cooperation with China Central Television 30 October Heavy Metal, chemist Neil Ward of the University of Surrey, who found abnormal pregnancies; medical doctor Robin Russell-Jones of the Campaign for Lead Free Air; environmental chemist Brian Davies of the University of Bradford; footage from the 1971 BBC A Public Poison, with chemist Derek Bryce-Smith, and Patrick Lawther of St Bartholomew's Hospital; Gloria all'Egitto from Aida by Giuseppe Verdi, with the assembly line of the Rover 800; Robin Brundle; Eric Fountain of Vauxhall Motors; Ojos Criollos by Louis Moreau Gottschalk. Narrated by Catherine Robins, produced by Michael Blakstad, made by Workhouse Productions 13 November Free Flight, about gliding, with Derek Piggott in a Rolladen-Schneider LS4 at Booker Gliding Centre in Buckinghamshire; in the UK there were about 350,000 flights and 2 deaths each year; a Schleicher ASW 24 in a wind tunnel with Loek Boermans at TU Delft Faculty of Aerospace Engineering in the Netherlands; the Schleicher ASH 25 with glider pilot John Jeffries at London Gliding Club west of Dunstable; at Wasserkuppe, a 3,000 ft mountain in the east of Hesse in the centre of Germany is where gliding mostly developed in the 1920s by the Deutsche Forschungsanstalt für Segelflug, due to German powered-aircraft manufacturing being legally restricted; nearby at Poppenhausen, Hesse is Alexander Schleicher GmbH & Co, with designer Gerhard Waibel, where gliders had wings made from carbon fibre, and covered in kevlar for torsional stiffness; the first glider of a contemporary design was the Akaflieg Stuttgart fs24 in 1951. Narrated by Robert Gary 20 November Chaos, Tim Palmer of the ECMWF; mathematician Robert L. Devaney; German mathematician Heinz-Otto Peitgen and fractal geometry; strange attractors in dynamical systems, such as weather systems; David Rand of the University of Warwick, and period-doubling bifurcation, discovered in 1975 by mathematician Mitchell Feigenbaum discovered; fractal landscapes; British mathematician Michael Barnsley, and affine transformations, which are applied to digital image processing; the chaos game; Soviet physicist Lev Landau; physicist Harry Swinney of the University of Texas; economist James B. Ramsey; Ian Stewart of the University of Warwick, and the unpredictable rotation of Hyperion. Written, produced and directed by Chris Haws, the programme was made by Independent Communications Associates (InCA). In 1989, it won the SciTech Award for best scientific documentary. 27 November The Art of Deception, about camouflage, deception, decoys and stealth. The Northrop Grumman B-2 Spirit was first displayed on Tuesday 22 November 1988, just five days before the programme was aired. Featured interviewees include: Richard P. Hallion of Wright-Patterson Air Force Base; Peter Varnish of the Admiralty Research Establishment at Funtington in West Sussex; defence writer Antony Preston; Roy Behrens of the Art Academy of Cincinnati; Lt Col Chris Nash of Surveillance, Target Acquisition, Night Observation and Counter-surveillance (STANOC); Major William Marshak of the AAMRL - now the 711th Human Performance Wing; Captain Brian Perowne, commanding officer of HMS Brazen (F91); aviation writer Bill Sweetman, and Commander Patrick Walker, commanding officer of HMS Trafalgar (S107) a Royal Navy hunter-killer submarine; John Hall of the Admiralty Research Establishment (former Admiralty Experiment Works) at Haslar. Narrated by Nick Chilvers, Written, produced and directed by Chris Haws, made by InCA and WGBH Boston
== Importance == Proteomic profiling is important in the advancement of our understanding of biological processes and mechanisms of disease. It helps in pathogen identification, thereby enhancing diagnostics and vaccine development by revealing protein interactions and functions related to virulence. Protein profiling has greatly helped in the early detection of cancers by using specific proteins found in the blood plasma. Recent studies have developed proteome-based tests with a high degree of accuracy in the detection of early stage cancers, using panels of proteins that distinguish cancerous from normal samples. For example, it has recently been demonstrated that using panels of ten sex-specific proteins, early-stage cancer could be identified with up to 93% accuracy in males and 84% in females at high specificity levels.
Neutron radiation has been reported in cold fusion experiments at very low levels using different kinds of detectors, but levels were too low, close to background, and found too infrequently to provide useful information about possible nuclear processes.
Sources: en.wikipedia.org
== Structure == Alginic acid is a linear copolymer with homopolymeric blocks of (1→4)-linked β-D-mannuronate (M) and α-L-guluronate (G) residues, respectively, covalently linked together in different sequences or blocks. The monomers may appear in homopolymeric blocks of consecutive G-residues (G-blocks), consecutive M-residues (M-blocks) or alternating M and G-residues (MG-blocks). α-L-guluronate is the C-5 epimer of β-D-mannuronate.
==== 2020 ==== Scientists report, using public biological data on 1.75 m people with known lifespans overall, to have identified 10 genomic loci which appear to intrinsically influence healthspan, lifespan, and longevity – of which half have not been reported previously at genome-wide significance and most being associated with cardiovascular disease – as well as haem metabolism as a promising candidate for further research within the field. Scientists report that after mice exercise their livers secrete the protein GPLD1, which is also elevated in elderly humans who exercise regularly, that this is associated with improved cognitive function in aged mice and that increasing the amount of GPLD1 produced by the mouse liver in old mice could yield many benefits of regular exercise for their brains – such as increased BDNF-levels, neurogenesis, and improved cognitive functioning in tests. Scientists report that yeast cells of the same genetic material and within the same environment age in two distinct ways, describe a biomolecular mechanism that can determine which process dominates during aging and genetically engineer a novel aging route with substantially extended lifespan. Reprogramming progress Scientists show that expression of nuclear reprogramming factors can lead to rapid and broad amelioration of cellular aging. A study shows that reprogramming induced with the OSK-genes can restore youthful epigenetic patterns as well as revert age-related vision loss.
Hong Kong generates most of its electricity locally. The vast majority of this energy comes from fossil fuels, with 46% from coal and 47% from petroleum. The rest is from other imports, including nuclear energy generated in mainland China. Renewable sources account for a negligible amount of energy generated for the territory. Small-scale wind-power sources have been developed, and a small number of private homes and public buildings have installed solar panels. With few natural lakes and rivers, high population density, inaccessible groundwater sources, and extremely seasonal rainfall, the territory lacks a reliable freshwater supply. The Dong River in Guangdong supplies 70% of the city's water, with the remaining demand met by harvesting rainwater locally. Toilets in most built-up areas of the territory flush with seawater, which reduces freshwater use. Broadband Internet access is widely available, with 99.3% of households connected. Connections over fibre-optic infrastructure are increasingly prevalent, contributing to the high regional average connection speed of 21.9 Mbit/s (the world's fourth-fastest). Mobile-phone use is ubiquitous; there are almost 22 million mobile-phone accounts registered in Hong Kong, which is almost triple the territory's population.
=== Ectendomycorrhiza === Although the Hartig net forms outside the root cells, penetration of plant cortical cells occasionally occurs. Many species of ectomycorrhizal fungi can function either as ectomycorrhizas or in the penetrative mode typical of arbuscular mycorrhizas, depending on the host. Because these associations represent a form of symbiosis in between arbuscular mycorrhizas and ectomycorrhizas, they are termed ectendomycorrhizas.
== History == Estradiol cypionate was patented by Upjohn in 1952, with a priority date of 1951. It was first introduced for medical use by Upjohn in 1952 under the brand name Depo-Estradiol in the United States. Subsequently, it was also marketed in other countries such as European countries and Japan. The first clinical reports of estradiol cypionate were published in 1952 and thereafter. It was initially known as estradiol cyclopentylpropionate (ECP), and did not become known as estradiol cypionate until over a decade later in the mid-to-late 1960s. Along with estradiol valerate (1954) and estradiol benzoate (1933), estradiol cypionate has become one of the most commonly used esters of estradiol. When estradiol cypionate was to be combined with medroxyprogesterone acetate as a once-a-month injectable contraceptive, there was a problem in that estradiol cypionate was prepared as an oil solution while medroxyprogesterone acetate was used as a microcrystalline aqueous suspension. This issue was resolved by switching to a microcrystalline aqueous suspension in the case of estradiol cypionate, allowing it to be combined with medroxyprogesterone acetate in a single suspension. As a result, single-drug preparations of estradiol cypionate are oil solutions, while the combination of estradiol cypionate and medroxyprogesterone acetate are microcrystalline aqueous suspensions.
Sources: en.wikipedia.org
ACC Synthase is 450-516 amino acid long sequence depending on the species of plant from which it is extracted. Though it is comparable in the species in which it is found, its COOH-terminal domain is more variable, leading to differences such as oligomerization. The COOH-terminal domain is responsible for oligomerization. In most ACC Synthase producing cells, ACC Synthase exists as a dimer. However, in some we find a monomer ("which is more active and efficient [than its dimer counterpart"). The structure of ACS has been largely determined via X-ray crystallography. Conservation of the residues in ACS's catalytic domain and sequence homology suggest that ACS catalyzes the synthesis of ACC in a similar fashion as other enzymes that require PLP as a cofactor. However, unlike many other PLP-dependent enzymes, Lys (278) is not the only residue that interacts with the substrate. The proximity of the electronegative oxygen from Tyr (152) to the C-γ-S bond suggests a crucial role in the formation of ACC. X-ray crystallography with aminoethoxyvinylglycine (AVG) a competitive inhibitor confirmed Tyrosine's role in the γ elimination. As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes PDB: 1B8G, PDB: 1IAX, PDB: 1IAY, PDB: 1M4N, PDB: 1M7Y, and PDB: 1YNU.
The third major group of regulatory RNAs is called enhancer RNAs. It is not clear at present whether they are a unique category of RNAs of various lengths or constitute a distinct subset of lncRNAs. In any case, they are transcribed from enhancers, which are known regulatory sites in the DNA near genes they regulate. They up-regulate the transcription of the gene(s) under control of the enhancer from which they are transcribed.
A blood glucose meter is an electronic device for measuring the blood glucose level. A relatively small drop of blood is placed on a disposable test strip which interfaces with a digital meter. Within several seconds, the level of blood glucose will be shown on the digital display. Needing only a small drop of blood for the meter means that the time and effort required for testing are reduced and the compliance of diabetic people to their testing regimens is improved significantly. Blood glucose meters provide results in various units such as eAG (mg/dL) and eAG (mmol/L), and may also estimate A1C levels. These measurements can aid in classifying blood glucose levels as normal, prediabetic, or diabetic, facilitating effective diabetes management for users. While some models offer interpretative features that indicate the health status based on these results, not all meters provide this functionality, focusing instead on providing raw glucose measurements. Users of blood glucose meters without interpretative features can utilize online calculators to determine their blood glucose status based on measured values. The cost of using blood glucose meters is believed to be a cost-benefit relative to the avoided medical costs of the complications of diabetes. Recent advances include:
13. Ir Med J. 2026 Sep 28;119(8):160. Non-Arteritic Anterior Ischaemic Optic Neuropathy Associated with Semaglutide use. Kearney M, Smyth NM, Hassan HSA, Khan MS. PRESENTATION: Non-arteritic ischaemic optic neuropathy (NAION) is a common cause of acute, painless monocular visual disturbance in older adults. This case discusses a woman in her 70s with vascular risk factors who presented with a three-day history of progressive left sided visual disturbance. Examination demonstrated a left relative afferent pupillary defect and inferior quadrantopia. DIAGNOSIS: Haematological investigations and neuroimaging were unremarkable. Formal ophthalmological assessment demonstrated superior optic disc swelling with an inferior visual field defect, consistent with NAION. TREATMENT: The patient had been taking semaglutide, as prescribed, for the six months prior to presentation. This was identified as a potential contributory agent and was discontinued. Visual acuity partially improved following cessation of semaglutide. DISCUSSION: This case seeks to highlight a possible association between semaglutide use and NAION. Although causality remains unproven, it underscores the importance of pharmacovigilance when manging patients presenting with ophthalmological symptoms.
Sources: en.wikipedia.org
Identification usually combines reverse-phase high-performance liquid chromatography with mass spectrometry. The copper content can be measured separately by inductively coupled plasma mass spectrometry or atomic absorption spectroscopy. The combination helps distinguish the intact complex from free peptide or free copper.
Light, oxygen, moisture, extreme pH, and elevated temperature can promote degradation or change copper coordination. Aqueous solutions are more vulnerable than dry solid because water enables hydrolysis and oxidation. Freeze-thaw cycling can also reduce sample quality.
A certificate of analysis summarizes tests performed by a supplier, but it does not guarantee that the material is suitable for every use. Methods, limits, and reporting practices differ between laboratories. Independent verification or raw data review is often needed for critical applications.
The colour comes from electronic transitions in the coordinated copper(II) ion. Ligand field effects absorb part of the visible spectrum. A colourless or greenish sample may indicate degraded material.