This is a working overview of intranasal delivery, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-09-30 and is reviewed periodically as new material appears.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应,Semax 属于这一路线。鼻内给药是其主要使用方式,俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上,样本规模与终点设置同西方试验惯例存在差异,国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理,部分东欧国家留有使用记录;欧盟与美国未批准其作为药物上市,市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录,跨境携带则受目的地药品法规约束。
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构,不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
Semax 是一种人工合成的七肽,氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro,单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物,但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly,Semax 替换了中间两个残基,并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发,相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性,而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示,这一方向促成了多个相关短肽的合成与筛选,而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上,包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升,但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验,人体对照研究数量有限。因此,该化合物的作用机制在文献中属于活跃讨论,而非已经确立的定论。
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
=== United States === Since the early 1980s, the purchase and use of PCP in the U.S. has not been available to the general public. Nowadays, most of the PCP used in the U.S. is restricted to the treatment of utility poles and railroad ties. In the United States, any drinking-water supply with a PCP concentration exceeding the MCL, 1 ppb, must be notified by the water supplier to the public. Disposal of PCP and PCP-contaminated substances are regulated under RCRA as F-listed (F021) or D-listed (D037) hazardous wastes. Bridges and similar structures such as piers can still be treated with pentachlorophenol.
=== Mortality === In the United States, deaths linked to methadone more than quadrupled in the five-year period between 1999 and 2004. According to the U.S. National Center for Health Statistics, as well as a 2006 series in the Charleston Gazette (West Virginia), medical examiners listed methadone as contributing to 3,849 deaths in 2004. That number was up from 790 in 1999. Approximately 82 percent of those deaths were listed as accidental, and most deaths involved combinations of methadone with other drugs (especially benzodiazepines). Although deaths from methadone are on the rise, methadone-associated deaths are not being caused primarily by methadone intended for methadone treatment programs, according to a panel of experts convened by the Substance Abuse and Mental Health Services Administration, which released a report titled "Methadone-Associated Mortality, Report of a National Assessment". The consensus report concludes that "although the data remains incomplete, National Assessment meeting participants concurred that methadone tablets or Diskets distributed through channels other than opioid treatment programs most likely are the central factors in methadone-associated mortality." In 2006, the U.S. Food and Drug Administration issued a caution about methadone, titled "Methadone Use for Pain Control May Result in Death." The FDA also revised the drug's package insert. The change deleted previous information about the usual adult dosage.
== Research == In 2015, Merck reported results in thirteen cancer types; much attention was given to early results in head and neck cancer. As of May 2016, pembrolizumab was in phase IB clinical trials for triple-negative breast cancer (TNBC), gastric cancer, urothelial cancer, and head and neck cancer (all under the "Keynote-012" trial) and in phase II trial for TNBC (the "Keynote-086" trial). At ASCO, in June 2016, Merck reported that the clinical development program was directed to around 30 cancers and that it was running over 270 clinical trials (around 100 in combination with other treatments) and had four registration-enabling studies in process. Results of a phase III clinical trial in triple-negative breast cancer were reported in October 2019. Results of a phase II clinical trial in Merkel-cell carcinoma were reported in June 2016. Results of a clinical trial in people with untreatable metastases arising from various solid tumors were reported in 2017. A clinical phase III trial in combination with epacadostat, an Indoleamine 2,3-dioxygenase (IDO1) inhibitor to treat melanoma was completed in 2019. In 2021, researchers reported the results of a five-year follow-up study. In January 2022, a combination clinical trial of pembrolizumab and NL-201, a de novo protein undergoing a phase I clinical trial in people with advanced, relapsed or refractory solid tumors. In March 2023, Merck reported the results of NRG-GY018, a phase III clinical trial in people with stage three to four or recurrent endometrial carcinoma.
Sources: en.wikipedia.org
Most LFTs are intended to operate on a purely qualitative basis. However, it is possible to measure the intensity of the test line to determine the quantity of analyte in the sample. Handheld diagnostic devices known as lateral flow readers are used by several companies to provide a fully quantitative assay result. By utilizing unique wavelengths of light for illumination in conjunction with either CMOS or CCD detection technology, a signal-rich image can be produced of the actual test lines. Using image processing algorithms specifically designed for a particular test type and medium, line intensities can then be correlated with analyte concentrations. One such handheld lateral flow device platform is made by Detekt Biomedical L.L.C. Alternative non-optical techniques are also able to report quantitative assays results. One such example is a magnetic immunoassay (MIA) in the LFT form also allows for getting a quantified result. Reducing variations in the capillary pumping of the sample fluid is another approach to move from qualitative to quantitative results. Recent work has, for example, demonstrated capillary pumping with a constant flow rate independent from the liquid viscosity and surface energy.
== Distribution and habitat == Vanilla planifolia is a native of the neotropical realm, from southern Mexico through Central America, Colombia, and the northern portions of Brazil. Previously it had been thought to be native to just southern Mexico and Belize. Because of cultivation, V. planifolia has additionally spread to tropical areas across the world, primarily in south Florida, the Cayman Islands, the Dominican Republic, Jamaica, Puerto Rico, tropical portions of Peru, Ecuador, Venezuela, French Guiana, Suriname, and Guyana in the Americas, but also the Democratic Republic of the Congo, Madagascar, Comoros, Bangladesh, the Malay Peninsula, the island of Java, the Chagos Archipelago, Cook Island, New Guinea, and New Caledonia. Vanilla planifolia requires a humid, warm tropical climate and grows best between 20 and 30 °C (68 and 86 °F) in humid conditions. It can only accept a minimum of 10 °C (50 °F) and a maximum of 33 °C (91 °F). Minimum rainfall requirements are about 2000 mm per year. For good growth it prefers well-draining soils with a pH between 6.0 and 7.0 and plenty of available calcium and potassium. The natural altitude range is from 150 to 900 meters. To trigger flowering it requires a dry period in the spring. Due to human land uses for crops and timber the required habitat for Vanilla planifolia has become very reduced and fragmented. The number of mature individuals in the wild is declining and the amount of suitable habitat also continues to decline. The IUCN formally assessed the species as Endangered in 2017, publishing their assessment in 2020.
According to The Washington Post, the coalition forces regularly use "torture-like" methods during the interrogation of suspects. Such methods were reportedly applied to people to find the hiding place of Saddam Hussein in Operation Red Dawn. British troops have also on occasion been accused of abusing Iraqi detainees. Such treatment violates article 17 of the Third Geneva Convention and the USA and Britain's official policies on combat and occupation. Despite numerous complaints by Amnesty International and Human Rights Watch, it took a year before the first US soldier was court-martialed for their actions concerning abuse of Iraqis.
Sources: en.wikipedia.org
The Statute of the Court and TFEU require judges are appointed only if they have no political occupation, with independence "beyond doubt". They are selected for renewable six-year terms by "common accord" of governments, with the advice of seven EU or member state judges that the Council and Parliament selects. The Rules of Procedure of the Court of Justice, article 11, says the court is usually organised into chambers of 3 or 5 judges each. A "grand chamber" of 15 more senior judges sit on questions of "difficulty or importance", or those requested by member states. The court's president and vice-president are elected by other judges for renewable 3-year terms by secret ballot. Judges can only be dismissed if all other judges and Advocates General unanimously agree. Advocates General are appointed by the court to give reasoned submissions on cases, especially involving new points of law. Unlike judges on the Court, they write opinions as themselves, rather than collectively, and often with a command of prose and reason, and while not binding are often followed in practice. In addition, each judge has secretaries or referendaires who research and write. Unlike the UK where judges always write their own opinions, referendaires often assist drafting the judgments in the Court of Justice. The Court's Translation Directorate will translate every final judgment into the 24 official languages of the European Union.
== Treatment == Benign tumors typically need no treatment unless they cause problems such as seizures, discomfort or cosmetic concerns. Surgery is usually the most effective approach and is used to treat most benign tumors. In some cases, other treatments may be used. Adenomas of the rectum may be treated with sclerotherapy, in which chemicals are used to shrink blood vessels in order to cut off the blood supply. Most benign tumors do not respond to chemotherapy or radiation therapy, although there are exceptions; benign intercranial tumors are sometimes treated with radiation therapy and chemotherapy under certain circumstances. Radiation can also be used to treat hemangiomas in the rectum. Benign skin tumors are usually surgically resected but other treatments such as cryotherapy, curettage, electrodesiccation, laser therapy, dermabrasion, chemical peels and topical medication are used.
creatine + phosphate Thus, the two substrates of this enzyme are N-phosphocreatine and H2O, whereas its two products are creatine and phosphate. This enzyme belongs to the family of hydrolases, specifically those acting on phosphorus-nitrogen bonds. The systematic name of this enzyme class is phosphamide hydrolase. This enzyme is also called creatine phosphatase.
Sources: en.wikipedia.org
不存在。它是依据 ACTH 的一段序列人工设计的分子,天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号,而非天然物质名。
Semax 对应 ACTH 第 4 至第 10 位的片段,并在两端做了替换与延长,使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物,需要医生开具处方。多数其他国家把它当作研究化合物,不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
Reversed-phase high-performance liquid chromatography is the standard method, with detection in the ultraviolet range. Peak area percentage yields a purity figure for the main component. Mass spectrometry is normally run alongside to confirm molecular identity.