The short version of FSFI desire score fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-20. Anything still debated is marked as such rather than presented as settled.
Handling procedures emphasize minimizing moisture uptake, since the dried solid is hygroscopic and can draw water when warmed to room temperature before a vial is opened. Laboratories record lot number, purity, counter-ion content, and residual solvent data supplied by the producer. Impurity profiles are compared run to run, and any shift in retention time or peak shape prompts re-verification against a reference standard. Certificates of analysis are treated as claims to be checked rather than accepted at face value.
Identity and purity testing for this peptide typically relies on reversed-phase high-performance liquid chromatography with ultraviolet detection, reported as area-percent purity. Mass spectrometry, usually in tandem mode, confirms molecular mass and supports quantification in biological matrices. Sequence confirmation may use peptide mapping after enzymatic digestion, while nuclear magnetic resonance and circular dichroism supply supplementary structural detail. No single technique establishes identity alone, so laboratories compare retention time, mass, and fragment pattern against a verified reference standard.
Development began with intranasal formulations investigated for erectile dysfunction, but blood pressure elevation limited that route and prompted a switch to subcutaneous delivery. Clinical testing then shifted toward hypoactive sexual desire disorder in premenopausal women, and a subcutaneous product received United States approval in 2019. Later trials examined other populations with mixed results, and questions about effect size, durability and patient selection remain open in the peer-reviewed literature. Research interest continues in parallel with the broader melanocortin field, where several synthetic analogues are studied together.
PT-141 is the research code for bremelanotide, a cyclic heptapeptide derived from alpha-melanocyte-stimulating hormone. The molecule belongs to the melanocortin receptor agonist family and shows highest affinity for the MC4 receptor subtype, with weaker activity at MC1, MC3 and MC5. Its structure retains the core His-Phe-Arg-Trp sequence that defines melanocortin recognition, while cyclization and terminal modifications improve metabolic stability relative to the parent hormone. Early work classified the compound as a centrally acting agent rather than a peripherally acting vasodilator, which shaped subsequent development priorities.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white solid | Lyophilized powder form |
| Solubility class | Freely soluble in water | Also dissolves in polar organic solvents |
| Typical storage temperature | Minus 20 degrees Celsius or lower | Desiccated and protected from light |
| Typical analytical method | Reversed-phase HPLC with UV detection | Purity reported by area normalization |
| Common synonyms | PT-141; bremelanotide | Research code and assigned generic name |
Clinical research typically uses randomised, double-blind, placebo-controlled designs. The most common primary endpoint is the desire domain score of the Female Sexual Function Index, sometimes paired with a distress measure. Secondary outcomes include arousal, satisfaction, and event-based counts of satisfying sexual episodes. Across trials, average improvements are modest and individual responses vary widely. Whether benefits persist beyond a few months, and whether they depend on baseline hormone status, remain open questions rather than settled findings.
Melanocortin receptors form a family of five G-protein-coupled receptors designated MC1 through MC5. Bremelanotide binds most strongly at MC4R and MC1R, with weaker activity reported at MC3R and MC5R. MC4R is expressed in hypothalamic nuclei that coordinate energy balance and aspects of sexual behaviour. The prevailing interpretation is that central MC4R activation, rather than peripheral vascular effects alone, drives the reported changes in desire. This account remains partly inferential, since direct receptor-level measurement in living humans is not practical.
After subcutaneous administration, plasma concentrations rise within roughly thirty minutes and the elimination half-life is short, on the order of two to three hours. Reported physiological responses include transient increases in blood pressure and nausea, which tended to diminish with repeated dosing in trial settings. Because the peptide clears quickly, effects are not expected to persist long after a dose. Absorption from non-injected routes is poorly characterised, and nasal delivery produced variable plasma levels in older work.
Development of the peptide passed through several delivery formats, including an intranasal version tested in early trials and an injectable version that entered later clinical study. Regulatory approval for a subcutaneous product in the United States was granted in 2019 after review of controlled trials in premenopausal women. Outside the clinic, the compound circulates in research and non-pharmaceutical markets under its code name, where identity and purity vary considerably between suppliers. Synonyms appearing across technical literature include bremelanotide, PT-141, and Palatin 141.
PT-141 is the research designation for bremelanotide, a synthetic cyclic heptapeptide developed as a melanocortin receptor agonist. The peptide contains seven amino acids with an internal lactam bridge that constrains the backbone into a stable ring. Cyclisation of this kind improves resistance to enzymatic degradation relative to linear analogues. The compound was first explored for effects on melanin production, because several melanocortin receptors influence pigmentation. Its later association with sexual desire emerged from observations made during that early work, and the molecule became the subject of a separate development programme.
Bremelanotide is a moderately large peptide with a molecular mass near 1025 daltons. In lyophilised form it appears as a white to off-white powder and is freely soluble in water and other polar solvents. The intact lactam ring is essential for receptor affinity, while linearised fragments bind far more weakly. Solutions are sensitive to extremes of pH and to prolonged exposure to light and heat, so handling typically involves buffered conditions and cold storage. Its short plasma half-life reflects rapid distribution and clearance rather than chemical breakdown inside the vial.
Bremelanotide is a cyclic heptapeptide that binds several melanocortin receptors rather than one. In vitro assays report agonist activity at MC1R, MC3R, MC4R and MC5R, with MC4R generally treated as the subtype most relevant to sexual effects. MC4R is expressed in hypothalamic nuclei involved in appetite, energy balance and motivated behaviour, which provides a plausible route for central action. Selective MC4R agonists studied in animals produce comparable behavioural changes, supporting that interpretation.
How receptor activation translates into a change in desire is not established in detail. Proposed steps include modulation of dopaminergic signalling in reward circuits and downstream effects on autonomic tone. Human data consist mainly of clinical trials measuring self-reported outcomes rather than direct measurements of brain activity or transmitter release. The transient rise in blood pressure sometimes observed after administration is likewise reported consistently but explained only partly by known melanocortin pathways.
Melanocortin receptors form a family of five G-protein-coupled proteins, labelled MC1R through MC5R, that respond to peptides derived from pro-opiomelanocortin. Alpha-melanocyte-stimulating hormone and adrenocorticotropic hormone are the best-known endogenous ligands. The receptors are distributed differently across tissues, so a single agonist can produce effects in the brain, skin, adrenal gland and vasculature. This distribution explains why one peptide can influence both pigmentation and motivated behaviour.
Bremelanotide, developed under the code PT-141, is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone. Its structure is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH, with a lactam bridge joining the aspartate and lysine side chains. The molecule has the formula C50H68N14O10 and a monoisotopic mass near 1025 daltons. It is commonly prepared as the acetate salt and appears as a white to off-white lyophilised powder in solid form. The free acid is the pharmacologically relevant species, while the counter-ion improves handling and dissolution.
Early research on PT-141 grew out of work on melanotan II, a related cyclic peptide studied for pigmentation. Investigators observed that centrally acting melanocortin agonists also influenced sexual behaviour in animal models, and the programme shifted toward that endpoint. A nasal formulation was evaluated in clinical trials but showed inconsistent absorption, and later studies used subcutaneous administration instead. Regulatory approval in the United States followed in 2019 for a defined population of premenopausal women with acquired, generalised hypoactive sexual desire disorder. That approval was specific to that group rather than a broad indication.
==== Carbon-sulfur ==== Prenylcysteine lyase (PCLase) catalyzes the cleavage of prenylcysteine (a protein modification) to form an isoprenoid aldehyde and the freed cysteine residue on the protein target. The FAD is non-covalently bound to PCLase. Not many mechanistic studies have been done looking at the reactions of the flavin, but the proposed mechanism is shown below. A hydride transfer from the C1 of the prenyl moiety to FAD is proposed, resulting in the reduction of the flavin to FADH2. COformED IS a carbocation that is stabilized by the neighboring sulfur atom. FADH2 then reacts with molecular oxygen to restore the oxidized enzyme.
Autotransporter proteins are outer membrane or secreted proteins found in a broad variety of Gram-negative bacteria. These proteins contain three structural motifs: a signal sequence, a passenger domain located at the N-terminal, and a translocator or autotransporter domain located at the C-terminal, forming a beta barrel structure. These structures promote the protein self-transport. Autotransporter proteins are usually related to virulence functions. This fact, their interaction with host cells and the broad occurrence of autotransporter encoding genes, bring up the possibility to represent therapeutic targets for the design of vaccines against Gram-negative pathogens. Two of the families in which the MEROPS database classifies asparagine peptide lyases are autotransporter proteins, families N4 and N6. Family N4 includes secreted virulence factors, or autotransporters, from enterobacteria. Their only proteolytic activity is releasing the virulence factor from the precursor, enabling it to be secreted. The active site residues in family N4 asparagine peptide lyases are N1100, Y1227, E1249 and R1282. Family N6 includes autoprocessing endopeptidases involved in type III protein secretion system, in which autoproteolysis is essential for mediating the secretion of proteins. Type III secretion system secretes proteins directly into host cells by an injectisome, a hollow tubular structure that penetrates into the host cell. Secreted proteins can pass through the injectisome into the host cell cytoplasm.
Nando's opened its first restaurants within the United Kingdom, in 1992, in the west London suburbs of Ealing and Earls Court, initially focusing on takeaway food. The UK arm, owned by the Enthoven family via a private equity company, struggled until chairman Dick Enthoven put his son Robert in control. The focus then moved from takeaways to a mixed-service (counter ordering and table service) model. This decision was taken after Nando's partnered with Harrison, a branding and design agency. They also advised Nando's to design each restaurant individually so no two restaurants were the same, a brand characteristic of the chain. In 2013, the company employed around 8,000 staff in the UK and had over 280 branches, with about 60 serving food conforming with Islamic dietary laws. In 2010, Nando's UK won the Sunday Times's 'best place to work' award in the big company category. Its sauces and marinades were also retailed in UK supermarkets. Nando's claims to have the largest collection of South African art in the UK, with over 5,000 works displayed in restaurants; original artworks are commissioned by the company. In March 2020, all of Nando's UK restaurants closed temporarily due to nationwide lockdown rules introduced by the government to limit the spread of COVID-19. In late April 2020, Nando's reopened select locations for delivery and collection services, with many more locations opening throughout May. In early July 2020, the restaurant chain started reopening a few of its outlets for eat-in service.
Independent Order of Sons of Abraham - Founded in 1892 by a group of Jewish men who were already members of the Masons, Sons of Benjamin, and the Order of B'rith Abraham. Membership in 1899 almost exclusively in New York and Brooklyn, numbered about 2,400 divided equally between men and women. Independent Order of Sons of Benjamin - Founded in 1877 in New York by a group of men who were already members of the Brith Abraham. By 1899 it had spread to the "principal cities of the United States and the Dominion of Canada." It authorized the creation of female lodges, of which there were about 20 in 1899. In 1899 there were about 18,000 male members and 2,500 women. In 1918 it had 800 members in 25 lodges, of which 450 were located in New York City with 18 lodges. Its headquarters in 1918 were at 953 Third Avenue. Offered the "usual secret society forms, and privileges". The emblem was a triangle between the letters F and P with an L under it. Offered insurance against death under the Metropolitan Life Insurance Company. Independent Western Star Order - Founded in 1894. The Eastern Division was headquartered at 40 Rivington Street. Had 21,000 members in 1918, with 2000 members in 24 lodges in New York City. Offered accident, death, and burial insurance May or may not be related to an order of the same name operating out of Chicago. Independent Workmens Circle - Founded in 1906 in Boston. Open to working men and women and "those in sympathy with the cause of labor". In 1923 had 77 lodges with 5,726 benefit members. Headquarters 86 Leverett Street, Boston.
Acute inflammation is characterized by marked vascular changes, including vasodilation, increased permeability and increased blood flow, which are induced by the actions of various inflammatory mediators. Vasodilation occurs first at the arteriole level, progressing to the capillary level, and brings about a net increase in the amount of blood present, causing the redness and heat of inflammation. Increased permeability of the vessels results in the movement of plasma into the tissues, with resultant stasis due to the increase in the concentration of the cells within blood – a condition characterized by enlarged vessels packed with cells. Stasis allows leukocytes to marginate (move) along the endothelium, a process critical to their recruitment into the tissues. Normal flowing blood prevents this, as the shearing force along the periphery of the vessels moves cells in the blood into the middle of the vessel.
Sources: en.wikipedia.org
The Spy Who Came In from the Cold is a 1965 British spy film directed and produced by Martin Ritt, adapted by Paul Dehn and Guy Trosper from the 1963 novel by John le Carré. It stars Richard Burton, Claire Bloom, and Oskar Werner, and features Sam Wanamaker, Cyril Cusack, Rupert Davies, George Voskovec, and Peter van Eyck in supporting roles. The film depicts British MI6 agent Alec Leamas' (Burton) mission as a faux defector who is given the task of sowing damaging disinformation about a powerful East German intelligence officer (Werner). As part of a charade, Leamas is apparently dismissed from the British secret intelligence service and becomes an embittered alcoholic. He also strikes up a relationship with Nan Perry (Bloom), a British communist. He is soon approached by East German agents in Britain, and he allows himself to be recruited and taken to continental Europe to sell his secrets for money. The plots of the rival spy agencies unfold, and prove more complicated than Leamas expected. The Spy Who Came In from the Cold was a box-office success, receiving positive reviews and several awards, including four BAFTA Awards for Best British Film, Best Actor (for Burton), Best Cinematography, and Best Production Design. For their performances, Burton was also nominated for the Academy Award for Best Actor while Werner won the Golden Globe Award for Best Supporting Actor. The film was named one of the top ten films of 1965 by the National Board of Review in the United States.
Reproductive Medicine: In 2024, a study demonstrated that SeV-mediated RNA delivery of the Kitl gene successfully re-initiated oogenesis and restored fertility in congenitally and chemotherapy-induced infertile female mice without genomic integration. Oncology: A 2024 study found that SeV provides more robust and consistent gene delivery into human pancreatic cancer cells than adeno-associated virus (AAV) or lentiviral vectors, regardless of tumor subtype. CRISPR-Cas9 Delivery: A next-generation "interferon-silent" and temperature-sensitive (ts) SeV platform was introduced in 2024, achieving over 90% editing efficiency in primary human hematopoietic stem and progenitor cells (HSPCs). In 2025, this ts SeV platform was further applied to deliver CRISPR/Cas9 for precise engineering of the human cytomegalovirus (HCMV) genome, bypassing traditional bacterial artificial chromosome (BAC) constraints and enabling editing in diverse cell types.
== External links == Skin graft. MedlinePlus Medical Encyclopedia. Parts of this US Federal Government public domain text were used in the article. An introduction to the use of vacuum assisted closure.
==== Extrusion-based printing ==== Although there are different approaches to extrusion based printing, these approaches follow the same basic procedures. The platform on which food is printed consists of a standard 3-axis stage with a computer controlled extrusion head. This extrusion head pushes food materials through a nozzle typically by way of compressed air or squeezing. The nozzles can vary with respect to what type of food is being extruded or the desired printing speed (typically the smaller the nozzle the longer the food printing will take). As the food is printed, the extrusion head moves along the 3-axis stage printing the desired food. Some printed food requires additional processing such as baking or frying before consumption. Extrusion based food printers can be purchased for household use, are typically compact in size, and have a low maintenance cost. Comparatively, extrusion based printing provides the user with more material choices. However, these food materials are usually soft, and as a result, makes printing complex food structures difficult. In addition, long fabrication times and deformations due to temperature fluctuations with additional baking or frying require further research and development to overcome.
=== Simplified clinical approach === Kalra has developed several clinically applicable concepts that simplify obesity management, including bariatric triage, gut guardianship, medical gastronomy, and obesity-friendly language. He has addressed the pathogenesis, comorbidities, and complications of obesity in multiple review papers, including a recent review on MASLD in Endocrine Clinics of North America. Several papers led by Kalra serve as practical guides for clinicians new to obesity management, outlining stepwise protocols for setting up obesity clinics and evaluating and managing obesity.
Sources: en.wikipedia.org
Chemical degradation such as hydrolysis and oxidation proceeds more slowly as temperature falls. Cold storage also limits microbial growth in reconstituted material. Repeated warming should be avoided because thermal cycling stresses the peptide.
Retention time supports consistency but does not establish structure by itself. A different compound can elute at a similar time under one set of conditions. Mass spectrometry or comparison with a verified standard is normally required alongside the chromatographic result.
The lactam bridge constrains the peptide backbone and limits attack by some exopeptidases. It does not protect against hydrolysis of amide bonds inside the ring or against oxidative modification of susceptible residues. Stability therefore still depends heavily on storage conditions.
The code designates bremelanotide, a cyclic heptapeptide melanocortin receptor agonist. It served as an internal research identifier before the compound entered formal clinical development. The code and the generic name refer to the same molecule.