A practical reference on assay standardization: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-09-09. Anything still debated is marked as such rather than presented as settled.
Tesamorelin is a synthetic analog of growth hormone-releasing hormone, a peptide hormone produced by the hypothalamus. The molecule retains the 44-amino-acid sequence of human GHRH and carries a trans-3-hexenoyl modification at its N-terminus. This modification increases resistance to enzymatic degradation and extends the peptide's functional stability relative to native GHRH. The compound is supplied as a lyophilized powder for reconstitution and subcutaneous administration in clinical settings. Its development code was TH9507, and it belongs to the GHRH analog class. It is not a growth hormone product; instead, it acts upstream to stimulate endogenous growth hormone release.
Clinical interest in tesamorelin arose from the need to address visceral adiposity in people living with HIV. Antiretroviral therapy improved survival but was associated in some patients with central fat accumulation, altered lipid profiles, and metabolic complications. This condition, often called HIV-associated lipodystrophy, involves excess visceral adipose tissue that is difficult to manage through diet and exercise alone. Investigators evaluated tesamorelin because GHRH analogs can stimulate growth hormone secretion and influence fat distribution without direct liposuction or invasive procedures.
A Phase 3 program led to regulatory approval in the United States in 2010 for reduction of excess visceral abdominal fat in adults with HIV and lipodystrophy. Subsequent studies examined effects on liver fat, muscle area, and metabolic markers, with mixed findings for some endpoints. Long-term cardiovascular outcomes and effects on mortality remain uncertain because most trials were relatively short and focused on imaging-based fat measurements. Use in populations without HIV has been studied experimentally but is not part of the approved indication.
Insulin-like growth factor 1 is produced largely in the liver in response to growth hormone signaling. Its concentration shifts over days rather than minutes, which makes it practical for tracking changes across a study period. Interpretation still depends on age, nutritional status, and concurrent illness, all of which independently affect the marker. Reference ranges are therefore stratified, and comparisons are usually made within an individual over time rather than against a single population threshold.
Assays for these markers differ in calibration and antibody specificity, so results from different platforms are not always interchangeable. Reported values can shift when a laboratory changes method, even without any biological change. Studies that span long periods or multiple sites often need cross-validation of assays. This methodological variability is a recognized limitation when comparing findings across published reports, and it remains a topic of ongoing standardization work.
Measuring the effect of a growth hormone-releasing hormone analogue requires markers that reflect pituitary output rather than the peptide itself. The two most frequently used are growth hormone and insulin-like growth factor 1. Growth hormone fluctuates sharply across the day and responds to sleep, stress, and meals, so isolated readings can be difficult to interpret. Insulin-like growth factor 1 changes more slowly and is often treated as the more stable integrated marker of axis activity.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | Approximately 5,136 Da | Based on the 44-amino-acid peptide backbone and N-terminal modification. |
| Appearance | White to off-white lyophilized powder | Usually supplied in single-use vials for reconstitution. |
| Solubility | Freely soluble in water; slightly soluble in some organic solvents | Peptide nature supports aqueous reconstitution. |
| Typical storage | 2–8 °C, protected from light | Refrigeration reduces degradation; avoid freezing unless specified. |
| Common analytical method | Reverse-phase high-performance liquid chromatography | Used for identity, purity, and quantification. |
| Synonyms | Tesamorelin, TH9507, GHRH(1-44) analog | Generic descriptors; avoid proprietary names. |
Tesamorelin is a synthetic peptide of forty-four amino acids whose sequence reproduces human growth hormone-releasing hormone. Its distinguishing feature sits at the amino terminus, where a trans-3-hexenoyl group replaces the free amine. That acylation slows cleavage by dipeptidyl peptidase IV, an enzyme that otherwise removes the first two residues and inactivates the natural hormone quickly. The modified peptide therefore persists longer in circulation while keeping the same receptor target. It is handled as a lyophilized solid and dissolved shortly before use.
Signaling begins at the GHRH receptor, a class B G protein-coupled receptor displayed on somatotroph cells of the anterior pituitary. Receptor occupancy activates Gs proteins, which raise adenylyl cyclase activity and intracellular cyclic AMP, in turn driving protein kinase A dependent pathways. The downstream output is synthesis and pulsatile secretion of growth hormone into the bloodstream. Hepatic tissue and peripheral sites respond by increasing insulin-like growth factor 1 production. Somatostatin and IGF-1 itself supply negative feedback that caps the size and duration of each secretory burst.
Growth hormone released from the pituitary stimulates the liver and other tissues to produce insulin-like growth factor 1, a stable circulating protein that serves as a practical marker of activity. Clinical studies therefore track IGF-1 concentrations alongside the hormone itself, and they commonly measure body composition with imaging rather than relying on body weight alone. Visceral adipose tissue, the fat surrounding abdominal organs, is quantified by computed tomography in the studies that supported approval. Adverse effects reported in trials include injection-site reactions, joint pain, and increases in blood glucose, which is why monitoring accompanies use.
Questions remain about how much of the observed fat reduction reflects direct GHRH-receptor signaling versus the downstream growth hormone and IGF-1 surge. It is also unclear whether the compound produces meaningful benefit in populations without lipodystrophy, since trials in cognitive impairment did not reach their stated goals. Long-term effects on glucose metabolism and on cardiovascular outcomes are not fully characterized. Published work generally describes effects on surrogate markers rather than on hard clinical endpoints, and independent replication of some findings is limited.
In the coastal areas of the southeast (such as Florida, the Carolinas and Louisiana), bears inhabit a mixture of flatwoods, bays and swampy hardwood sites. In the northeastern part of the range (the United States and Canada), prime habitat consists of a forest canopy of hardwoods such as beech, maple, birch and coniferous species. Corn crops and oak-hickory mast are also common sources of food in some sections of the northeast; small, thick swampy areas provide excellent refuge cover largely in stands of white cedar. Along the Pacific coast, redwood, Sitka spruce and hemlocks predominate as overstory cover. Within these northern forest types are early successional areas important for American black bears, such as fields of brush, wet and dry meadows, high tidelands, riparian areas and a variety of mast-producing hardwood species. The spruce-fir forest dominates much of the range of the American black bear in the Rockies. Important non-forested areas here are wet meadows, riparian areas, avalanche chutes, roadsides, burns, sidehill parks and subalpine ridgetops. In areas where human development is relatively low, such as stretches of Canada and Alaska, American black bears tend to be found more regularly in lowland regions. In parts of eastern Canada, especially Labrador, American black bears have adapted exclusively to semi-open areas that are more typical habitat in North America for brown bears (likely due to the absence there of brown and polar bears, as well as other large carnivore species).
=== Tourism === Tourism is a major part of Hong Kong's economy, accounting for 5% of its GDP. In 2016, 26.6 million visitors contributed HK$258 billion (US$32.9 billion) to the territory, making Hong Kong the 14th-most popular destination for international tourists. It is the most popular Chinese city for tourists, receiving over 70% more visitors than its closest competitor Macau. The city is ranked as one of the most expensive cities for expatriates. However, since 2020, there has been a sharp decline in incoming visitors due to tight COVID-19 travel restrictions. In an attempt to attract tourists back to Hong Kong, the Hong Kong government announced plans to give away 500,000 free airline tickets in 2023. Hong Kong was the second most visited city in the world with 23.2 million visitors in 2025.
==== Colorado law ==== In Colorado, for medical purposes, cannabis tea is a "Medical Marijuana Infused Product" which is "a product infused with medical marijuana that is intended for use or consumption other than by smoking, including edible products, ointments, and tinctures. These products, when manufactured or sold by a licensed medical marijuana center or a medical marijuana-infused product manufacturer, shall not be considered a food or drug for the purposes of the "Colorado Food and Drug Act", part 4 of article 5 of title 25, C.R.S." Colorado currently stands as one of 33 states that have laws legalizing marijuana as of 2018.
Sources: en.wikipedia.org
Bukele registered as a presidential pre-candidate on 26 June 2023 with Nuevas Ideas; Ulloa registered as Bukele's vice-presidential pre-candidate. Nuevas Ideas nominated Bukele and Ulloa as their presidential and vice-presidential candidates on 9 July. The party began registering Bukele and Ulloa's candidacies with the TSE on 26 October, the last day to do so. On 3 November 2023, the TSE registered their candidacies amidst opposition requests to reject Bukele's candidacy. On 30 November 2023, the Legislative Assembly granted Bukele and Ulloa leaves of absence to focus on their re-election campaign. The leave went into effect the following day and Bukele's presidential powers were suspended. The Legislative Assembly named Claudia Rodríguez de Guevara, Bukele's presidential secretary, as the presidential designate; Rodríguez was the first woman in Salvadoran history to hold presidential power. Her appointment was criticized by some lawyers and opposition politicians as unconstitutional. Including Bukele, there were six presidential candidates in the 2024 election. His primary opponents were ARENA's Joel Sánchez, a businessman, and the FMLN's Manuel Flores, a former legislator. Bukele led Sánchez and Flores by large margins in opinion polling before the election. Bukele promised to maintain the gang crackdown, invest in infrastructure projects, and promote economic growth during his second term. On 4 February 2024, he won re-election with 84.65 percent of the vote. Bukele was the first Salvadoran president to be re-elected since Maximiliano Hernández Martínez in 1944.
The players have access to a limited selection of Half-Life's weaponry to assist them in the game. The game is unique in the context of the Half-Life series in that it is the only game divided into separate missions, each with a specific objective to pursue, instead of consisting of a single unbroken narrative. How players perform in each mission is ranked at the conclusion of the level as a grade from "A" to "F". This score is based on each player's accuracy with weapons, the number of kills they acquired and the amount of damage they sustained during the course of the mission. Should players successfully complete the game's nine missions with "A" grades on every level, they are given access to a bonus cooperative mission, in which they can play as a pair of Vortigaunts, as well as the ability to play through the PlayStation 2 version of the original Half-Life as a Vortigaunt.
The HIC of leaf water is variable during the biosynthesis, and the enrichment in the whole leaf can be described by the equation, △Dleaf = △De × ([1 − e−p]/P) The typical δD of bulk plant is around −160‰, while δDs for cellulose and lignin are −110‰ and −70‰ respectively.
Sources: en.wikipedia.org
=== OSS-7: Dash7 open-source stack === The goal of the project is to provide a reference implementation of the DASH7 Alliance protocol. This implementation should focus on completeness, correctness and being easy to understand. Performance and code size are less important aspects. For clarity, a clear separation between the ISO layers is maintained in the code. The project is available on GitHub and is licensed under the Apache License, version 2.0.
Lateral flow assays have played a critical role in COVID-19 testing as they have the benefit of delivering a result in 15–30 minutes. The systematic evaluation of lateral flow assays during the COVID-19 pandemic was initiated at Oxford University as part of a UK collaboration with Public Health England. A study that started in June 2020 in the United Kingdom, FALCON-C19, confirmed the sensitivity of some lateral flow devices (LFDs) in this setting. Four out of 64 LFDs tested had desirable performance characteristics according to these early tests; the Innova SARS-CoV-2 Antigen Rapid Qualitative Test performed moderately in viral antigen detection/sensitivity with excellent specificity, although kit failure rates and the impact of training were potential issues. The Innova test's specificity is more widely publicised, but sensitivity in phase 4 trials was 50.1%. This describes a device for which one out of every two patients infected with COVID-19 and tested in real-world conditions would receive a false-negative result. After closure of schools in January 2021, biweekly LFTs were introduced in England for teachers, pupils, and households of pupils when schools re-opened on March 8, 2021 for asymptomatic testing. Biweekly LFT were made universally available to everyone in England on April 9, 2021. LFTs have been used for mass testing for COVID-19 globally and complement other public health measures for COVID-19. Some scientists outside government expressed serious misgivings in late 2020 about the use of Innova LFDs for screening for Covid.
The term diabetes is derived from the Ionic for 'siphon', meaning "to pass or run through". It reflects the dominant notion at the time that fluids consumed by the diabetic patient passed through the body unchanged, as if flowing through a tube or siphon. A number of conflicting accounts exist as to the first use of this term, placing the originator as either Apollonius of Memphis (fl. 3rd century BC), Demetrius of Apamea (fl. 100 BC), or Aretaeus of Cappadocia (fl. early 2nd century AD). In-depth probes of Greek etymology agree that the term came from Demetrius of Apamea, C. L. Gemmill (1972) states:Caelius Aurelianus prepared a Latin version of the works of Soranus. In the index of the Drabkin edition there is a subject heading "Diabetes," but on examination of the text this section could not be found (footnote 3, p. 776) except for a short paragraph. In this paragraph Caelius quotes Apollonius of Memphis as separating two forms of dropsy, one marked by retention of fluid and the other by the inability to retain fluid; the patient discharges whatever he drinks as if it were passed through a pipe. Apollonius lived in the second half of the third century B.C. Caelius Aurelianus continues by stating that Demetrius of Apamea distinguishes this disease from dropsy in which any fluid that is drunk is discharged as urine. Demetrius calls this condition diabetes. The time of Demetrius of Apamea is given as the first century B.C. None of his works have come down to us; we have only quotations in later authors.
== P == P24 – package insert – palliative – palliative care – pancreas – pancreatitis – pancytopenia – pandemic – pap smear – papilloma – parallel track – parasite – parenteral – paresthesia – passive immunity – passive immunotherapy – pathogen – pathogenesis – PBMC – PCP – PCR – Pediatric AIDS Clinical Trial Group (PACTG) – pelvic inflammatory disease – peptide – perianal – perinatal – perinatal transmission – peripheral neuritis – peripheral neuropathy – persistent generalized lymphadenopathy – PGL – phagocyte – phagocytosis – pharmacokinetics – phase I trials – phase II trials – phase III trials – phase IV trials – photosensitivity – PHS – pituitary gland – placebo – placebo controlled study – placebo effect – plasma – plasma cells – platelets – PML – Pneumocystis jiroveci pneumonia (formerly Pneumocystis carinii or PCP) – POL – polymerase – polymerase chain reaction (PCR) – polyneuritis – polypeptide – polyvalent vaccine – post-exposure prophylaxis (PEP) – PPD test – pre-conception counseling – preclinical – precursor cells – prevalence – primary HIV infection – primary isolate – primaquine – proctitis – prodrome – prodrug – progressive multifocal leukoencephalopathy (PML) – prophylactic drug – prophylaxis – protease – protease inhibitors – protease-sparing regimen – proteins – protocol – protozoa – provirus – pruritus – pseudo-Cushing's syndrome – pseudovirion – PUBMED – pulmonary – purified protein derivative (PPD)
Sources: en.wikipedia.org
It is a synthetic peptide analog of human growth hormone-releasing hormone. It is used clinically to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy. It works by stimulating pituitary growth hormone release.
Pivotal trials enrolled adults with HIV and excess visceral abdominal fat, often in the context of antiretroviral therapy. Participants were assessed mainly by computed tomography for visceral adipose tissue. The approved indication remains specific to that population.
Long-term effects on cardiovascular events, mortality, and sustained fat distribution are not well established. Most trials measured changes over months rather than years. Open questions also include whether benefits persist after treatment stops.
It varies slowly and reflects cumulative axis activity rather than momentary secretion. Growth hormone is released in pulses affected by sleep, stress, and meals, making single readings hard to interpret. The slower marker gives a more stable picture across a study period.