Transvestism is the practice of dressing and acting in a style or manner traditionally associated with the opposite sex. In some cultures, transvestism is practiced for religious, traditional or ceremonial reasons.

Though coined as late as the 1910s, the phenomenon is not new. It was referred to in the Hebrew Bible. The word has undergone several changes of meaning since it was first coined and is still used in a variety of senses. Today, the term "transvestite" is commonly considered outdated and derogatory, with the term "cross-dresser" used as a more appropriate replacement. This is because the term "transvestite" was historically used to diagnose medical disorders, including mental health disorders, and transvestism was viewed as a disorder, but the term "cross-dresser" was coined by the transgender community. In some cases, however, the term "transvestite" is seen as more appropriate for use by members of the transgender community instead of by those outside of the transgender community, and some have reclaimed the word.

To determine relative prevalences of different fetishes, Italian researchers obtained an international sample of 5,000 individuals from 381 fetish-themed discussion groups. The relative prevalences were estimated based on (a) the number of groups devoted to a particular fetish, (b) the number of individuals participating in the groups and (c) the number of messages exchanged. Within the sample population (a population of adults online involved in sexual discussion), 12 percent indicated a fetish related to an "object associated with the body + external event" . This includes, but is not limited to, objects such as underwear, socks, shoes, etc. (see Table 1 in the .pdf of the first article cited).

Males with late onset gender dysphoria "frequently" display transvestic fetishism.

Some male transvestic fetishists collect women's clothing, e.g. panties, nightgowns, babydolls, bridal gowns, slips, brassieres, and other types of nightwear, lingerie, stockings, pantyhose, shoes, and boots, items of a distinct feminine look and feel. They may dress in these feminine garments and take photographs of themselves while living out their fantasies.

According to DSM-IV, this fetishism was limited to heterosexual men; however, DSM-5 does not have this restriction, and opens it to women and men with this interest, regardless of their sexual orientation.

There are two key criteria before a psychiatric diagnosis of "transvestic fetishism" is made:

1. Individuals must be sexually aroused by the act of cross-dressing.

2. Individuals must experience significant distress or impairment – socially or occupationally – because of their behavior.

Transvestic fetishism is a psychiatric diagnosis applied to those who are thought to have an excessive sexual or erotic interest in cross-dressing; this interest is often expressed in autoerotic behavior. It differs from cross-dressing for entertainment or other purposes that do not involve sexual arousal, and is categorized as a paraphilia in the Diagnostic and Statistical Manual of the American Psychiatric Association. (Sexual arousal in response to donning sex-typical clothing is homeovestism.)

Therapeutic approaches for GIDC differ from those used on adults and have included behavior therapy, psychodynamic therapy, group therapy, and parent counseling. Proponents of this intervention seek to reduce gender dysphoria, make children more comfortable with their bodies, lessen ostracism, and reduce the child's psychiatric comorbidity. The majority of therapists currently employ these techniques. "Two short term goals have been discussed in the literature: the reduction or elimination of social ostracism and conflict, and the alleviation of underlying or associated psychopathology. Longer term goals have focused on the prevention of transsexualism and/or homosexuality."

Individual therapy with the child seeks to identify and resolve underlying factors, including familial factors; encourage identification by sex assigned at birth; and encourage same-sex friendships. Parent counseling involves setting limits on the child's cross-gender behavior; encouraging gender-neutral or sex-typical activities; examining familial factors; and examining parental factors such as psychopathology. Longtime researchers of gender identity disorder, Kenneth Zucker and Susan Bradley, state that it has been found that boys with gender identity disorder often have mothers who to an extent reinforced behavior more stereotypical of young girls. They also note that children with gender identity disorder tend to come from families where cross-gender role behavior was not explicitly discouraged. However, they also acknowledge that one could view these findings as merely indicative of the fact that parents who were more accepting of their child's cross-gender role behavior are also more likely to bring their children to a clinical psychiatrist as opposed to parents who are less accepting of cross-gender role behavior in their children (Bradley, Zucker, 1997). " Proponents acknowledge limited data on GIDC: "apart from a series of intrasubject behaviour therapy case reports from the 1970s, one will find not a single randomized controlled treatment trial in the literature" (Zucker 2001). Psychiatrist Domenico Di Ceglie opines that for therapeutic intervention, "efficacy is unclear," and psychologist Bernadette Wren says, "There is little evidence, however, that any psychological treatments have much effect in changing gender identity although some treatment centres continue to promote this as an aim (e.g. Zucker, & Bradley, 1995)." Zucker has stated that "the therapist must rely on the 'clinical wisdom' that has accumulated and to utilize largely untested case formulation conceptual models to inform treatment approaches and decisions."

Underwear fetishism is a sexual fetishism relating to undergarments, and refers to preoccupation with the sexual excitement of certain types of underwear, including panties, stockings, pantyhose, bras, or other items. Some people experience sexual excitement from wearing, while others get their excitement when observing or handling the underwear worn by another, or watching somebody putting underwear on/taking it off. Some may steal used underwear to get satisfaction. Not only does this include physical contact with the garment(s), or their wearers, but also includes arousal by printed or electronic image with depictions of underwear.

Underwear fetishism is not considered as paraphilia unless it causes distress or serious problems for the person or those associated with them.

Gender dysphoria in children or gender identity disorder in children (GIDC) is a formal diagnosis used by psychologists and physicians to describe children who experience significant discontent (gender dysphoria) with their biological sex, assigned gender, or both.

GIDC was formalized in the third revision of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-III) in 1980 and primarily referenced gender non-conforming behaviors. GIDC remained in the DSM from 1980 to 2013, when it was replaced with the diagnosis of "gender dysphoria" in the fifth revision (DSM-5), in an effort to diminish the stigma attached to gender variance while maintaining a diagnostic route to gender affirming medical interventions such as hormone therapy and surgery.

Controversy surrounding the pathologization and treatment of cross-gender identity and behaviors, particularly in children, has been evident in the literature since the 1980s. Proponents of more widespread GIDC diagnoses argue that therapeutic intervention helps children be more comfortable in their bodies and can prevent adult gender identity disorder. Opponents say that the equivalent therapeutic interventions with gays and lesbians (titled conversion or reparative therapy) have been strongly questioned or declared unethical by the American Psychological Association, American Psychiatric Association, American Association of Social Workers and American Academy of Pediatrics. The World Professional Association for Transgender Health (WPATH) states that treatment aimed at trying to change a person's gender identity and expression to become more congruent with sex assigned at birth "is no longer considered ethical." Critics also argue that the GIDC diagnosis and associated therapeutic interventions rely on the assumption that an adult transsexual identity is undesirable, challenging this assumption along with the lack of clinical data to support outcomes and efficacy.

Gender identity disorder in children is more heavily linked with adult homosexuality than adult transsexualism. According to limited studies, the majority of children diagnosed with GID cease to desire to be the other sex by puberty, with most growing up to identify as gay or lesbian with or without therapeutic intervention.

Andre Crawford (born March 20, 1962) is an American convicted serial killer, who killed 11 women between 1993 and 1999. Many of the women were prostitutes or drug addicts. He also had sex with their corpses.

Crawford had been placed in foster care as an infant after authorities found him living alone in squalor and after his mother admitted leaving him unattended for long periods of time. As a child he had lived with a foster family. As an adult, he became a transient, living in vacant buildings in Chicago.

He was accused of the murder of Evandry Harris, Patricia Dunn, Rhonda King, Angel Shatteen, Shaquanta Langley, Sonja Brandon, Nicole Townsend, Cheryl Cross, Tommie Dennis, Sheryl Johnson and Constance Bailey. He was linked by DNA to seven of the victims, and confessed to all 11 murders. He was convicted in December 2009. A 12th woman was attacked and left for dead on Thanksgiving 1997, but survived.

Hubert Geralds, Jr., 34, was convicted in 1997 of murdering six women in Chicago’s Englewood neighborhood. The first victim was Rhonda King. Under interrogation by police, he confessed to all six murders. In 1998 he was sentenced to death. In 2000 prosecutors moved to vacate the conviction for the King murder, because DNA linked her death to Andre Crawford. Geralds remained on death row for the other five murders, however.

Mme L. reports that “1, 2, 3 are children without fixed personalities; they play together. 4 is a good peaceful woman, absorbed by down-to-earth occupations and who takes pleasure in them. 5 is a young man, ordinary and common in his tastes and appearance, but extravagant and self-centered. 6 is a young man of 16 or 17, very well brought up, polite, gentle, agreeable in appearance, and with upstanding tastes; average intelligence; orphan. 7 is a bad sort, although brought up well; spiritual, extravagant, gay, likeable; capable of very good actions on occasion; very generous. 8 is a very dignified lady, who acts appropriately, and who is linked with 7 and has much influence on him. She is the wife of 9. 9 is the husband of 8. He is self-centred, maniacal, selfish, thinks only about himself, is grumpy, endlessly reproaching his wife for one thing or another; telling her, for example, that he would have been better to have married a 9, since between them they would have made 18 – as opposed to only 17 with her… 10, and the other remaining numerals, have no personifications”.

Cakins (1893) describes a case for whom “T’s are generally crabbed, ungenerous creatures. U is a soulless sort of thing. 4 is honest, but… 3 I cannot trust… 9 is dark, a gentleman, tall and graceful, but politic under his suavity” .

For synesthete MT “I [is] a bit of a worrier at times, although easy-going; J [is] male; appearing jocular, but with strength of character; K [is] female; quiet, responsible…” .

More recently AP has reported that February is “an introverted female”, while F is a “[male] dodgy geezer”. Similarly, May is reported to be “soft-spoken” and “girly” while M is an “old lady [who] natter[s] a lot”, and while August is “a boy among girls”, A is a female “mother type” (; ).

Ordinal-linguistic personification (OLP, or personification for short) is a form of synesthesia in which ordered sequences, such as ordinal numbers, days, months and letters are associated with personalities and/or genders (). Although this form of synesthesia was documented as early as the 1890s (; ) researchers have, until recently, paid little attention to this form (see History of synesthesia research).

Viet Nguyen (, February 25, 1981 – October 6, 2007) and Duc Nguyen (, born February 25, 1981) were a pair of conjoined twins born in Vietnam and surgically separated in 1988. Viet died in 2007 of natural causes.

Viet and Duc were born on February 25, 1981, in Kon Tum Province, Tây Nguyên, Vietnam. Viet was the elder and Duc was the younger of the two brothers. Their relatives claim that "the reason they became conjoined twins is the influence of Agent Orange that the U.S. military used as a defoliant during the Vietnam War". His mother was farming in the area doused with Agent Orange a year after the Vietnam War had ended. She also drank water from a well in that area. After that, Viet and Duc were born. On October 4, 1988, Viet and Duc were separated in the hospital in Ho Chi Minh City with the help of the Japanese Red Cross after Viet went into a coma.

Duc first entered junior high school, then dropped out and learned computer programming in a school. Now, he works at a hospital in Ho Chi Minh City. On December 16, 2006, he married Nguyen Thanh Tuyen in Ho Chi Minh City.

Viet's health problems continued after the separation, and he died due to liver failure and pneumonia on October 6, 2007, at the age of 26.

Foreign language anxiety, or xenoglossophobia, is the feeling of , worry, nervousness and apprehension experienced in learning or using a second or foreign language. The feelings may stem from any second language context whether it is associated with the productive skills of speaking and writing or the receptive skills of reading and listening.

Foreign language anxiety is a form of what psychologists describe as a "specific anxiety reaction". Some individuals are more predisposed to anxiety than others and may feel anxious in a wide variety of situations. Foreign language anxiety, however, is situation-specific and so it can also affect individuals who are not characteristically anxious in other situations.

No vaccines are currently available to protect against "S. pyogenes" infection, although research is underway to develop one. Difficulties in developing a vaccine include the wide variety of strains of "S. pyogenes" present in the environment and the large amount of time and people that will be needed for appropriate trials for safety and efficacy of the vaccine.

Rheumatic fever can be prevented by effectively treating strep throat with antibiotics.

In those who have previously had rheumatic fever, antibiotics in a preventative manner are occasionally recommended. As of 2017 the evidence to support long term antibiotics in those with underlying disease; however, is poor.

The American Heart Association suggests that dental health be maintained, and that people with a history of bacterial endocarditis, a heart transplant, artificial heart valves, or "some types of congenital heart defects" may wish to consider long-term antibiotic prophylaxis.

Uncombable hair syndrome, also known as Pili trianguli et canaliculi, Spun-glass hair, and Cheveux incoiffables, is a rare structural anomaly of the hair with a variable degree of effect. It was first reported in the early 20th century and was described in the 1970s. It becomes apparent from as little as 3 months to up to 12 years of age.

The hair is normal in quantity and is usually silvery-blond or straw-colored. It is disorderly, it stands out from the scalp, and cannot be combed flat. The underlying structural anomaly is longitudinal grooving of the hair shaft, which appears triangular in cross section. This is caused by mutations in one of three possible genes; "PADI3", "TGM" or "TCHH3." The characteristic hair shaft anomaly can be demonstrated in asymptomatic family members by scanning electron microscopy. To be noticeable, 50% of hairs must be affected by the structural abnormality. Improvement often occurs in later childhood. An autosomal dominant mode of inheritance has been suggested though an autosomal recessive pattern with varying degrees of penetrance has also been noted. The stiffness of the uncombable hair has been reasoned to be due to the triangular form of the hair shaft in cross section. It has been suggested that the condition may result from premature keratinization of the inner root sheath.

Osteolathyrism is a collagen cross-linking deficiency brought on by dietary over-reliance on the seeds of "Lathyrus sativus" or grass pea, a legume often grown as a famine crop in Asia and East Africa. Other members of the genus are also known to cause the disease, including "L. sylvestris", "L. cicera", and "L. clymenum". "L. sativus" grows well under famine conditions, often severe drought, where it is cultivated. The condition results in damage to bone and mesenchymal connective tissues. It is seen in people in combination with neurolathyrism and angiolathyrism in areas where famine demands reliance on a crop with known detrimental effects. It occurs in cattle and horses with diets overreliant upon the grass pea. Osteolathyrism is caused by a variety of osteolathyrogenic compounds, specifically excitatory amino-compounds. The most widely-studied of these compounds is beta-aminopropionitrile (BAPN), which exerts its deleterious effect by an unknown yet potently irreversible mechanism. Other instigators are ureides, semicarbazides and thiosemicarbazides, which are believed to chelate the prosthetic Cu(II)-bipyridine cofactor complex in the enzyme lysyl oxidase.

The disease used to be uniformly fatal, with a 5-year survival rate between 10 and 35%. As a result, treatment was radical surgery. New multidrug chemotherapy regimens with or without radiation therapy are now used in combination with less radical surgery with good results, although outcome data are not yet available.

The effects of these negative emotions may also lead to cross-cultural code-switching, in which bilingual people alter a language to their other language through their interactions with other bilinguals. Unlike linguistic code-switching, cross-cultural code-switching is the socio-linguistic phenomenon of changing culturally-ingrained behaviors in a foreign situation. Although cross-cultural code-switching possibly results from both positive and negative emotions, negative emotions are more common and more likely to affect the way a bilingual person speaks. Negative emotions include embarrassment, performance anxiety, guilt, distress and anxiety. "Molinsky identifies three psychological states that appraise under the influence of emotions while code-switching. These are: "experienced performance difficulty, face threat and identity conflict—all of which mediate the relationship between personal and contextual variables and the negative and positive emotions an individual experiences while code-switching".

There are three types of cross-cultural code-switching:

- situational code-switching

- conversational code-switching

- borrowing

This code-switching could be considered as an unconscious behavior because of its negative and usually threatening situations. In that sense, although code-switching results from foreign language anxiety, it is more often caused by external circumstances than by internal mental change.

Until more molecular and clinical studies are performed there will be no way to prevent the disease. Treatments are directed towards alleviating the symptoms. To treat the disease it is crucial to diagnose it properly. Orthopedic therapy and fracture management are necessary to reduce the severity of symptoms. Bisphosphonate drugs are also an effective treatment.

Pork–cat syndrome is an allergy to pork, usually post adolescence, that is caused by exposure to cats. Although first described in 1994, it was first documented in the U.S. by Scott Commins and Thomas Platts-Mills during their research on alpha-gal allergy.

It is called "pork–cat syndrome" because "almost all people with the condition are cat owners, and many have multiple cats. Some develop an allergic response to cat serum albumin (protein made by a cat’s liver) that cross-reacts with albumin in pork when someone consumes it, and can lead to severe or even fatal allergic reactions when pork is consumed."

Cross–McKusick–Breen syndrome (also known as "Cross syndrome", "hypopigmentation and microphthalmia", and "oculocerebral-hypopigmentation syndrome") is an extremely rare disorder characterized by white skin, blond hair with yellow-gray metallic sheen, small eyes with cloudy corneas, jerky nystagmus, gingival fibromatosis and severe mental and physical retardation.

It was characterized in 1967.

Sarcoma botryoides normally is found in children under 8 years of age. Onset of symptoms occurs at age 3 years (38.3 months) on average. Cases of older women with this condition have also been reported.

Exposure to antiretroviral treatments has led to the evolution of HIV in response to selection pressure that eliminates strains of HIV that do not express resistance mechanisms. Drug resistance occurs in all antiretroviral treatments if patients are non-adherent, meaning that they do not take their medication regimens as prescribed. Lack of adherence may result from unreliable access to the medication, due to prohibitive cost or inadequate supply.

Current medical and scientific opinion is mixed on the most effective treatment methods, but is focused on drug cocktails and the importance of first-line regimens . The World Health Organization advocates a public-health approach to HIV treatment in order to make treatment uniform and available to patients around the world. As of July 2017, the WHO is implementing the Global Action Plan on HIV drug resistance 2017-2021. It is a 5-year initiative intended to help countries around the world manage HIV drug resistance.

Among treatment methods, the World Health Organization acknowledges the importance of successful first-line treatments. First-line treatments are known to affect the virus’ future response to other treatments, making the effectiveness of first-line treatments an issue of vital importance. The most successful treatments are combinations of three drugs used simultaneously, as this greatly reduces the probability of the virus developing resistance.