SUMMARY / RELATED TOPICS

Agoraphobia

Agoraphobia is an anxiety disorder characterized by symptoms of anxiety in situations where the person perceives their environment to be unsafe with no easy way to escape. These situations can include open spaces, public transit, shopping centers, or being outside their home. Being in these situations may result in a panic attack; the symptoms occur nearly last for more than six months. Those affected will go to great lengths to avoid these situations. In severe cases people may become unable to leave their homes. Agoraphobia is believed to be due to a combination of environmental factors; the condition runs in families, stressful or traumatic events such as the death of a parent or being attacked may be a trigger. In the DSM-5 agoraphobia is classified as a phobia along with specific social phobia. Other conditions that can produce similar symptoms include separation anxiety, post-traumatic stress disorder, major depressive disorder; those affected are at higher risk of substance use disorder. Without treatment it is uncommon for agoraphobia to resolve.

Treatment is with a type of counselling called cognitive behavioral therapy. CBT results in resolution for about half of people. Agoraphobia affects about 1.7% of adults. Women are affected about twice as as men; the condition begins in early adulthood and becomes less common in old age. It is rare in children; the term "agoraphobia" is from Greek ἀγορά, agorā́, meaning a "public square," and -φοβία, -phobía, meaning "fear." Agoraphobia is a condition where sufferers become anxious in unfamiliar environments or where they perceive that they have little control. Triggers for this anxiety may include crowds, or traveling. Agoraphobia is but not always, compounded by a fear of social embarrassment, as the agoraphobic fears the onset of a panic attack and appearing distraught in public. Most of the time they avoid these areas and stay in the comfort of their safe haven their home. Agoraphobia is defined as "a fear, sometimes terrifying, by those who have experienced one or more panic attacks". In these cases, the sufferer is fearful of a particular place because they have experienced a panic attack at the same location at a previous time.

Fearing the onset of another panic attack, the sufferer is fearful or avoids a location. Some refuse to leave their homes in medical emergencies because the fear of being outside of their comfort areas is too great; the sufferers can sometimes go to great lengths to avoid the locations where they have experienced the onset of a panic attack. Agoraphobia, as described in this manner, is a symptom professionals check when making a diagnosis of panic disorder. Other syndromes like obsessive compulsive disorder or post-traumatic stress disorder can cause agoraphobia. Any irrational fear that keeps one from going outside can cause the syndrome. Agoraphobics may suffer from temporary separation anxiety disorder when certain other individuals of the household depart from the residence temporarily, such as a parent or spouse, or when the agoraphobic is left home alone; such temporary conditions can result in an increase in anxiety or a panic attack or feeling the need to separate themselves from family or maybe friends.

People with agoraphobia sometimes fear waiting outside for long periods of time. Agoraphobia patients can experience sudden panic attacks when traveling to places where they fear they are out of control, help would be difficult to obtain, or they could be embarrassed. During a panic attack, epinephrine is released in large amounts, triggering the body's natural fight-or-flight response. A panic attack has an abrupt onset, building to maximum intensity within 10 to 15 minutes, lasts longer than 30 minutes. Symptoms of a panic attack include palpitations, rapid heartbeat, trembling, vomiting, tightness in the throat, shortness of breath. Many patients report a fear of dying, fear of losing control of emotions or fear of losing control of behaviors. Agoraphobia is believed to be due to a combination of environmental factors; the condition runs in families, stressful or traumatic events such as the death of a parent or being attacked may be a trigger. Research has uncovered a link between agoraphobia and difficulties with spatial orientation.

Individuals without agoraphobia are able to maintain balance by combining information from their vestibular system, their visual system, their proprioceptive sense. A disproportionate number of agoraphobics have weak vestibular function and rely more on visual or tactile signals, they may become disoriented when visual cues are overwhelming. They may be confused by sloping or irregular surfaces. In a virtual reality study, agoraphobics showed impaired processing of changing audiovisual data in comparison with subjects without agoraphobia. Chronic use of tranquilizers and sleeping pills such as benzodiazepines has been linked to onset of agoraphobia. In 10 patients who had developed agoraphobia during benzodiazepine dependence, symptoms abated within the first year of assisted withdrawal. Alcohol use disorders are associated with panic with or without agoraphobia. Tobacco smoking has been associated with the development and emergence of agoraphobia with panic disorder.

Raissa L. Berg

Raissa L'vovna Berg was a Russian geneticist and evolutionary biologist. Raissa Berg was born in St. Petersburg, the second child of Lev Semenovitch Berg and Polina Abramovna Kotlovker, both natives of Bendery, within the Jewish Pale. In order to study at Moscow University, Lev Berg chose to convert to Lutheranism and became a noted geographer and ichthyologist; when Raissa Berg was six weeks old, her parents separated. Though her mother sued for custody, her father prevailed. Raissa and her brother Simon were baptized and raised by their father, paternal grandmother Klara L'vovna Berg, stepmother Maria Mikhailovna Ivanova, who Lev Berg married in 1923. Berg graduated from St. Petersburg's German Lutheran school in 1929, she earned a diploma in genetics from Leningrad University, where she studied under H. J. Muller. With the dissertation "Differences between wild and laboratory populations of Drosophila melanogaster: a hypothesis of genetic correlations," she earned a Candidate of Sciences degree from Leningrad State University.

She began work on a doctoral dissertation, "Species as an Evolving System," in the early 1940s and defended it in 1964, earning a Doctor of Sciences degree from Novosibirsk's Institute of Cytology and Genetics. After completing her studies in Leningrad, Berg moved to Moscow to work at the A. N. Severtsov Institute of Evolutionary Morphology under I. I. Schmalhausen; the Institute was evacuated to Kazakhstan in 1941, but the following year Berg returned to Moscow to work on her doctoral dissertation. From 1944-1947 she worked as a senior researcher at the Severtsov Institute and part-time at the Zoological Institute of Moscow University. Lysenkoism pressured Soviet geneticists. By the time of Berg's dismissal from Moscow University, "there was only one geneticist at Moscow University's Department of Darwinism and one geneticist at the Institute of Evolutionary Morphology, I was both of them." Berg continued botanical experiments to support her doctoral dissertation and published work relating to her father's expeditions.

In 1948, Berg began work as an associate professor of the Herzen Leningrad Pedagogical Institute, in 1949 moved to the All-Union Research Institute of Lake and River Fish Management. She worked at Leningrad State University. From 1964–1968, Berg headed the Laboratory of Population Genetics of the Institute of Cytology and Genetics and worked as a lecturer at Novosibirsk State University. After being forced out of Novosibirsk in 1968, Berg returned to Leningrad, she headed a group at the Agrophysical Institute of VASKhNIL from 1968-1970 and was a professor at Herzen Leningrad Pedagogical University from 1968–1974. In the mid-1970s, Berg emigrated to the United States, she held a position at the University of Wisconsin–Madison from 1975–1981, from 1984-1984 was a visiting professor at George Washington University. She traveled and lectured extensively before relocating to France in 1994. Berg was a non-conformist; the comparatively liberal Khrushchev regime and remote Novosibirsk Akademgorodok afforded her the opportunity to host gatherings of dissenter artists and writers.

Along with several dozen other researchers working within the Siberian Division of the Russian Academy of Sciences, Berg signed a letter protesting the closed trials of dissidents. In 1968 she was retired from her work. Berg wrote in defense of N. V. Timoféeff-Ressovsky, a Russian-born scientist working in Nazi Germany, she asserted that he was interested in pure research, politically opposed to the Third Reich, reasonably concerned for his safety in Stalin's Soviet Union, unfairly persecuted following World War II. In her memoir, Acquired Traits, Berg chronicled her own challenges working within the Soviet system. Berg married geneticist Valentin Sergeevich Kirpichnikov in 1945; the couple had two daughters and Maria Kirpichnikova, born in 1947 and 1948, respectively

Ceramide synthase 5

Ceramide synthase 5 is the enzyme encoded in humans by the CERS5 gene. CerS5 robustly synthesizes C16-ceramide, considered to be an important pro-apoptotic ceramide. De novo ceramide synthesis is an essential trigger for Bax activation in hypoxia/reoxygenation. Following hypoxia/reoxygenation, CerS5 expression is elevated. Upon knocking down acid sphingomyelinase and CerS5 in NTERA-2 cells, Bax localization to mitochondria was reduced, indicating the importance of CerS5 activity in the apoptosis pathway. CerS5 mRNA is found in all tissues and is expressed in muscle and brain. CerS5 is the major ceramide synthase detected in lung epithelia. Knock-down research in respiratory epithelium using CerS5 siRNA or fumonisin B1 reduced total CerS activity by 45% or 78% indicating that CerS5 indeed contributes to ceramide synthesis in lung. In the brain, CerS5 mRNA is detected in most cells within the white matter tissues. CerS5 sensitizes cells to the chemotherapeutic drugs doxorubicin and vincristine, but not to cisplatin or carboplatin.

A splice variant of CerS5 is expressed in lymphoma and other tumor cells and contribute to tumor recognition by the immune system. In response to upregulation of tumor suppressor protein p53, C16-ceramide levels were increased in leukemia and colon cancer cells, as were levels of CerS5 mRNA in the leukemia cells, but not in the colon cancer cells. For this reason, CerS5 looks like a promising target for the regulation of cancer and of cell death pathways