Premenstrual Syndrome (PMS) is a complex of symptoms that occur in the latter part of the luteal phase (the second half) of the menstrual cycle, typically starting 5-11 days before the onset of menses, and remitting shortly after the onset of menstruation. The symptoms can be physical, psychological, or behavioral and vary from mild to severe. They include but are not limited to: bloating, breast tenderness, cramps, headaches, mood swings, irritability, depression, anxiety, fatigue, changes in appetite, and difficulty concentrating.

The exact cause of PMS is not known, but it appears to be related to hormonal changes during the menstrual cycle, particularly fluctuations in estrogen and progesterone levels. Some women may be more susceptible to these hormonal shifts due to genetic factors, neurotransmitter imbalances, or other health conditions.

Treatment for PMS often involves a combination of lifestyle changes (such as regular exercise, stress management, and dietary modifications), over-the-counter pain relievers, and, in some cases, hormonal medications or antidepressants. It's important to consult with a healthcare provider for an accurate diagnosis and treatment plan.

Vitex, also known as chasteberry or Vitex agnus-castus, is not a medical term but a common herbal supplement. It is derived from the fruit of the Vitex agnus-castus tree, which is native to the Mediterranean region and parts of Asia.

The medical community has studied Vitex for its potential effects on various conditions, including premenstrual syndrome (PMS), menopausal symptoms, and irregular menstrual cycles. However, it's essential to note that the evidence supporting its use is mixed, and more research is needed to confirm its effectiveness and safety.

Vitex is thought to have dopamine-like effects on the hypothalamus, which may help regulate hormonal imbalances in some women. However, it can interact with other medications and has potential side effects, so it's crucial to consult a healthcare provider before taking Vitex or any herbal supplement.

Dysmenorrhea is a medical term that refers to painful menstrual cramps and discomfort during menstruation. It's one of the most common gynecological complaints among women of reproductive age. There are two types of dysmenorrhea: primary and secondary.

1. Primary Dysmenorrhea: This type is more common and occurs in women who have had normal, pelvic anatomy. The pain is caused by strong contractions of the uterus due to the production of prostaglandins (hormone-like substances that are involved in inflammation and pain). Primary dysmenorrhea usually starts soon after menarche (the beginning of menstruation) and tends to improve with age, particularly after childbirth.
2. Secondary Dysmenorrhea: This type is less common and occurs due to an underlying medical condition affecting the reproductive organs, such as endometriosis, uterine fibroids, pelvic inflammatory disease (PID), or adenomyosis. The pain associated with secondary dysmenorrhea tends to worsen over time and may be accompanied by other symptoms like irregular menstrual bleeding, pain during intercourse, or chronic pelvic pain.

Treatment for dysmenorrhea depends on the type and underlying cause. For primary dysmenorrhea, nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen can help alleviate pain by reducing prostaglandin production. Hormonal birth control methods like oral contraceptives and intrauterine devices (IUDs) may also be prescribed to reduce menstrual pain. For secondary dysmenorrhea, treatment typically involves addressing the underlying medical condition causing the pain.

The luteal phase is the second half of the menstrual cycle, starting from ovulation (release of an egg from the ovaries) and lasting until the start of the next menstruation. This phase typically lasts around 12-14 days in a regular 28-day menstrual cycle. During this phase, the remains of the dominant follicle that released the egg transform into the corpus luteum, which produces progesterone and some estrogen to support the implantation of a fertilized egg and maintain the early stages of pregnancy. If pregnancy does not occur, the corpus luteum degenerates, leading to a drop in hormone levels and the start of a new menstrual cycle.

The menstrual cycle is a series of natural changes that occur in the female reproductive system over an approximate 28-day interval, marking the body's preparation for potential pregnancy. It involves the interplay of hormones that regulate the growth and disintegration of the uterine lining (endometrium) and the release of an egg (ovulation) from the ovaries.

The menstrual cycle can be divided into three main phases:

1. Menstrual phase: The cycle begins with the onset of menstruation, where the thickened uterine lining is shed through the vagina, lasting typically for 3-7 days. This shedding occurs due to a decrease in estrogen and progesterone levels, which are hormones essential for maintaining the endometrium during the previous cycle.

2. Follicular phase: After menstruation, the follicular phase commences with the pituitary gland releasing follicle-stimulating hormone (FSH). FSH stimulates the growth of several ovarian follicles, each containing an immature egg. One dominant follicle usually becomes selected to mature and release an egg during ovulation. Estrogen levels rise as the dominant follicle grows, causing the endometrium to thicken in preparation for a potential pregnancy.

3. Luteal phase: Following ovulation, the ruptured follicle transforms into the corpus luteum, which produces progesterone and estrogen to further support the endometrial thickening. If fertilization does not occur within approximately 24 hours after ovulation, the corpus luteum will degenerate, leading to a decline in hormone levels. This drop triggers the onset of menstruation, initiating a new menstrual cycle.

Understanding the menstrual cycle is crucial for monitoring reproductive health and planning or preventing pregnancies. Variations in cycle length and symptoms are common among women, but persistent irregularities may indicate underlying medical conditions requiring further evaluation by a healthcare professional.

Euphausiacea is a taxonomic category, specifically an order, that includes various types of planktonic crustaceans commonly known as krill. These small, shrimp-like animals are found in oceans all over the world and play a crucial role in marine ecosystems as a key food source for many larger animals, including whales, seals, and fish.

Euphausiids, as they are sometimes called, have a transparent exoskeleton and a distinctive bioluminescent ability that they use for communication, attracting prey, and evading predators. They are filter feeders, consuming large quantities of phytoplankton and other small organisms.

Euphausiacea is part of the larger decapod group, which also includes crabs, lobsters, and shrimp. The study of these animals and their role in marine ecosystems is important for understanding ocean health and biodiversity.

A pessary is a medical device that is inserted into the vagina to provide support for the uterus, vaginal vault, or bladder. It is often used in the management of pelvic organ prolapse, urinary incontinence, and other gynecological conditions. Pessaries come in various shapes and sizes, and they are typically made of silicone, rubber, or plastic. They can be worn for extended periods of time and are usually removable and cleanable. The selection and fitting of a pessary should be performed by a healthcare professional, such as a gynecologist or nurse midwife.

The follicular phase is a term used in reproductive endocrinology, which refers to the first part of the menstrual cycle. This phase begins on the first day of menstruation and lasts until ovulation. During this phase, several follicles in the ovaries begin to mature under the influence of follicle-stimulating hormone (FSH) released by the pituitary gland.

Typically, one follicle becomes dominant and continues to mature, while the others regress. The dominant follicle produces increasing amounts of estrogen, which causes the lining of the uterus to thicken in preparation for a possible pregnancy. The follicular phase can vary in length, but on average it lasts about 14 days.

It's important to note that the length and characteristics of the follicular phase can provide valuable information in diagnosing various reproductive disorders, such as polycystic ovary syndrome (PCOS) or thyroid dysfunction.

Progesterone is a steroid hormone that is primarily produced in the ovaries during the menstrual cycle and in pregnancy. It plays an essential role in preparing the uterus for implantation of a fertilized egg and maintaining the early stages of pregnancy. Progesterone works to thicken the lining of the uterus, creating a nurturing environment for the developing embryo.

During the menstrual cycle, progesterone is produced by the corpus luteum, a temporary structure formed in the ovary after an egg has been released from a follicle during ovulation. If pregnancy does not occur, the levels of progesterone will decrease, leading to the shedding of the uterine lining and menstruation.

In addition to its reproductive functions, progesterone also has various other effects on the body, such as helping to regulate the immune system, supporting bone health, and potentially influencing mood and cognition. Progesterone can be administered medically in the form of oral pills, intramuscular injections, or vaginal suppositories for various purposes, including hormone replacement therapy, contraception, and managing certain gynecological conditions.

In medical and psychological terms, "affect" refers to a person's emotional or expressive state, mood, or dispositions that are outwardly manifested in their behavior, facial expressions, demeanor, or speech. Affect can be described as being congruent or incongruent with an individual's thoughts and experiences.

There are different types of affect, including:

1. Neutral affect: When a person shows no apparent emotion or displays minimal emotional expressiveness.
2. Positive affect: When a person exhibits positive emotions such as happiness, excitement, or enthusiasm.
3. Negative affect: When a person experiences and displays negative emotions like sadness, anger, or fear.
4. Blunted affect: When a person's emotional response is noticeably reduced or diminished, often observed in individuals with certain mental health conditions, such as schizophrenia.
5. Flat affect: When a person has an almost complete absence of emotional expressiveness, which can be indicative of severe depression or other mental health disorders.
6. Labile affect: When a person's emotional state fluctuates rapidly and frequently between positive and negative emotions, often observed in individuals with certain neurological conditions or mood disorders.

Clinicians may assess a patient's affect during an interview or examination to help diagnose mental health conditions, evaluate treatment progress, or monitor overall well-being.

A syndrome, in medical terms, is a set of symptoms that collectively indicate or characterize a disease, disorder, or underlying pathological process. It's essentially a collection of signs and/or symptoms that frequently occur together and can suggest a particular cause or condition, even though the exact physiological mechanisms might not be fully understood.

For example, Down syndrome is characterized by specific physical features, cognitive delays, and other developmental issues resulting from an extra copy of chromosome 21. Similarly, metabolic syndromes like diabetes mellitus type 2 involve a group of risk factors such as obesity, high blood pressure, high blood sugar, and abnormal cholesterol or triglyceride levels that collectively increase the risk of heart disease, stroke, and diabetes.

It's important to note that a syndrome is not a specific diagnosis; rather, it's a pattern of symptoms that can help guide further diagnostic evaluation and management.

Serotonin uptake inhibitors (also known as Selective Serotonin Reuptake Inhibitors or SSRIs) are a class of medications primarily used to treat depression and anxiety disorders. They work by increasing the levels of serotonin, a neurotransmitter in the brain that helps regulate mood, appetite, and sleep, among other functions.

SSRIs block the reuptake of serotonin into the presynaptic neuron, allowing more serotonin to be available in the synapse (the space between two neurons) for binding to postsynaptic receptors. This results in increased serotonergic neurotransmission and improved mood regulation.

Examples of SSRIs include fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram (Celexa), and escitalopram (Lexapro). These medications are generally well-tolerated, with side effects that may include nausea, headache, insomnia, sexual dysfunction, and increased anxiety or agitation. However, they can have serious interactions with other medications, so it is important to inform your healthcare provider of all medications you are taking before starting an SSRI.

Feminism is not a medical term, but rather a social and political movement that advocates for the equal rights, opportunities, and treatment of women. It is based on the belief that women should have the same social, economic, and political power as men. The feminist movement has made significant contributions to various fields, including medicine, by advocating for issues such as reproductive rights, gender equality in healthcare, and addressing sexism and discrimination in medical research and practice.

An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.

I'm sorry for any confusion, but "newspapers" and "medical" are not related. A newspaper is a periodically published printed or online publication that reports news and provides information on politics, local events, sports, arts, and entertainment, as well as advertising. If you have any medical questions or concerns, I would be happy to try to help answer them.

"History, 19th Century" is not a medical term or concept. It refers to the historical events, developments, and figures related to the 1800s in various fields, including politics, culture, science, and technology. However, if you are looking for medical advancements during the 19th century, here's a brief overview:

The 19th century was a period of significant progress in medicine, with numerous discoveries and innovations that shaped modern medical practices. Some notable developments include:

1. Edward Jenner's smallpox vaccine (1796): Although not strictly within the 19th century, Jenner's discovery laid the foundation for vaccination as a preventive measure against infectious diseases.
2. Germ theory of disease: The work of Louis Pasteur, Robert Koch, and others established that many diseases were caused by microorganisms, leading to the development of antiseptic practices and vaccines.
3. Anesthesia: In 1842, Crawford Long first used ether as an anesthetic during surgery, followed by the introduction of chloroform in 1847 by James Simpson.
4. Antisepsis and asepsis: Joseph Lister introduced antiseptic practices in surgery, significantly reducing postoperative infections. Later, the concept of asepsis (sterilization) was developed to prevent contamination during surgical procedures.
5. Microbiology: The development of techniques for culturing and staining bacteria allowed for better understanding and identification of pathogens.
6. Physiology: Claude Bernard's work on the regulation of internal body functions, or homeostasis, contributed significantly to our understanding of human physiology.
7. Neurology: Jean-Martin Charcot made significant contributions to the study of neurological disorders, including multiple sclerosis and Parkinson's disease.
8. Psychiatry: Sigmund Freud developed psychoanalysis, a new approach to understanding mental illnesses.
9. Public health: The 19th century saw the establishment of public health organizations and initiatives aimed at improving sanitation, water quality, and vaccination programs.
10. Medical education reforms: The Flexner Report in 1910 led to significant improvements in medical education standards and practices.