Top videos
More than three decades on from its first outbreak, HIV/AIDS remains a prevalent killer, even in the developed world, and a pressing scientific challenge to understand and treat. The rate of infection, especially among young people, is increasing, and in parts of Africa in particular, it remains an epidemic-scale killer. Yet a cure could be just around the corner, and scientists are optimistic that the virus’ days might be numbered. Is HIV here to stay, or will it be consigned to history like Smallpox? Produced by ABC Australia - Ref-6621 Journeyman Pictures brings you highlights from the cutting-edge science series, ‘Catalyst’, produced by our long-term content partners at ABC Australia. Every day we’ll upload a new episode that takes you to the heart of the most intriguing and relevant science-related stories of the day, transforming your perspective of the issues shaping our world.
The hepatitis E virus, responsible for major epidemics of viral hepatitis in subtropical and tropical countries, was cloned only 7 years ago.1 Hepatitis E was found to belong to the family of Caliciviridae, which includes the Norwalk virus—a common cause of gastroenteritis in humans—and consists of a single, plus-strand RNA genome of approximately 7.2 kb without an envelope (Fig. 1). The virus contains at least three open reading frames encoding viral proteins against which antibodies are made on exposure. These antibodies, especially those against the capsid protein derived from the second open reading frame2 and a protein of unknown function derived from the third open reading frame, are detected by currently available serologic assays. Retrospective studies on stored sera of past epidemics of viral hepatitis in Mexico, Africa, Afghanistan, Pakistan, India, Bangladesh, Burma, Nepal, and Borneo have revealed that all were caused by strains of hepatitis E. In addition, hepatitis E was found to be responsible for the hepatitis epidemic in the southern part of Xinjiang, China, in which 120,000 persons became infected between September 1986 and April 1988.3 Hepatitis E predominantly affects young adults (15 to 40 years old). The symptoms of hepatitis E are similar to those of hepatitis A. Frequently, a prodrome consisting of anorexia, nausea, low-grade fever, and right upper abdominal pain is present 3 to 7 days before jaundice develops. Aminotransferase levels peak (usually between 1,000 and 2,000 U/L) near the onset of symptoms; bilirubin levels (10 to 20 mg/dL) peak later. Jaundice usually resolves after 1 to 2 weeks. In about 10% of cases, the disease is fulminant—especially in pregnant women, among whom mortality rates as high as 20% due to hemorrhagic and thrombotic complications have been reported. No evidence has suggested that hepatitis E can cause chronic infection. Transmission is by the fecal-oral route, predominantly through fecally contaminated drinking water supplies. In addition, however, preliminary reports have suggested transmission of the hepatitis E virus through blood transfusions. Volunteer studies confirmed the presence of the virus in serum and feces before and during clinical disease.4 The virus is shed into feces approximately 1 week before symptoms develop. The incubation period varies from 2 to 9 weeks (mean duration, approximately 45 days). Until now, a few reports had described symptomatic hepatitis E acquired in Europe;5, 6 all patients with symptomatic hepatitis E in the United States were travelers returning from Mexico, Africa, or the Far East, in whom hepatitis E developed after their return home.7 In this issue of the Mayo Clinic Proceedings (pages 1133 to 1136), Kwo and associates describe a case of hepatitis E in a man who had not left the United States during the previous 10 years. Specific serologic tests for hepatitis E virus IgG (enzyme immunoassays and a fluorescent antibody blocking assay) and IgM8 (US strain-specific enzyme-linked immunosorbent assay with use of synthetic polypeptides deduced from the viral genome, as shown in Figure 1), developed at Abbott Laboratories (IgG and IgM) as well as at the Centers for Disease Control and Prevention (IgG), were used to prove that the patient indeed had acute hepatitis E. Researchers at Abbott Laboratories have prepared a report that describes most of the viral genome in this patient (Fig. I).8 Their results are interesting because this strain from the United States differs considerably from hepatitis E strains isolated in Mexico, Burma, Pakistan, or China. Furthermore, the sequence of the US strain is highly homologous (98% and 94% homology at the amino acid level to the second and third open reading frames, respectively) to a recently isolated hepatitis E strain from American swine.9 This finding suggests that, in the United States, hepatitis E is a zoonosis with the swine population as one of its hosts. This relationship would confirm earlier studies in Asia, where swine were also found to carry variants of the hepatitis E virus.10 Why are these two recent discoveries important for medicine in the United States? First, other sporadic, locally acquired cases of acute hepatitis may be caused by hepatitis E. Second, these back-to-back discoveries strongly suggest that a common natural host for hepatitis E is present in countries with more moderate climates. Because swine do not seem to experience any symptoms associated with infection and because symptoms in humans can be minor or absent, we now may also have an explanation for the 1 to 2% of positive hepatitis E serologic results in blood donors in the United States,11 Netherlands,12 and Italy,6 countries with large swine staples. Clearly, more research needs to be done to confirm this hypothesis. Third, in countries with more moderate climates, hepatitis E may often result in a subclinical infection. Is this variation in manifestation due to less virulent strains, and do sequence variations determine virulence? Fourth, swine may be used as an animal model for study of the disease as well as vaccine development.
Asthma is a condition in which your airways narrow and swell and produce extra mucus. This can make breathing difficult and trigger coughing, wheezing and shortness of breath. For some people, asthma is a minor nuisance. For others, it can be a major problem that interferes with daily activities and may lead to a life-threatening asthma attack. Asthma can't be cured, but its symptoms can be controlled. Because asthma often changes over time, it's important that you work with your doctor to track your signs and symptoms and adjust treatment as needed.
The term dermoid cyst does not appear to be restricted to a single kind of lesion nor is it used in only a single medical discipline. The term dermoid cyst can be found in the vocabulary of dermatologists, dermatopathologists, general pathologists, gynecologists, neurosurgeons, or pediatricians. If asked, all of these clinicians would most probably define and describe dermoid cysts differently. For example, gynecologists and general pathologists might say that a dermoid cyst is a cystic tumor of the ovary. In contrast, neurosurgeons tend to view a dermoid cyst is associated with a congenital cyst of the spine or an intracranial congenital cyst. For pediatricians and dermatologists, dermoid cyst means subcutaneous cysts, which are usually congenital.[1]
A sleep disorder, or somnipathy, is a medical disorder of the sleep patterns of a person or animal. Some sleep disorders are serious enough to interfere with normal physical, mental, social and emotional functioning. Polysomnography and actigraphy are tests commonly ordered for some sleep disorders.
Atrial fibrillation (also called AFib or AF) is a quivering or irregular heartbeat (arrhythmia) that can lead to blood clots, stroke, heart failure and other heart-related complications. Some people refer to AF as a quivering heart. An estimated 2.7 million Americans are living with AF.
Thoracic outlet syndrome is a group of disorders that occur when blood vessels or nerves in the space between your collarbone and your first rib (thoracic outlet) are compressed. This can cause pain in your shoulders and neck and numbness in your fingers. Common causes of thoracic outlet syndrome include physical trauma from a car accident, repetitive injuries from job- or sports-related activities, certain anatomical defects (such as having an extra rib), and pregnancy. Sometimes doctors can't determine the cause of thoracic outlet syndrome. Treatment for thoracic outlet syndrome usually involves physical therapy and pain relief measures. Most people improve with these approaches. In some cases, however, your doctor may recommend surgery.
Thoracic outlet syndrome is a disorders that occur when blood vessels or nerves in the space between your collarbone and your first rib (thoracic outlet) are compressed. This can cause pain in your shoulders and neck and numbness in your fingers. Common causes of thoracic outlet syndrome include physical trauma from a car accident, repetitive injuries from job- or sports-related activities, certain anatomical defects (such as having an extra rib), and pregnancy. Sometimes doctors can't determine the cause of thoracic outlet syndrome. Treatment for thoracic outlet syndrome usually involves physical therapy and pain relief measures. Most people improve with these approaches. In some cases, however, your doctor may recommend surgery.
Menorrhagia is the medical term for menstrual periods with abnormally heavy or prolonged bleeding. Although heavy menstrual bleeding is a common concern among premenopausal women, most women don't experience blood loss severe enough to be defined as menorrhagia. With menorrhagia, every period you have causes enough blood loss and cramping that you can't maintain your usual activities. If you have menstrual bleeding so heavy that you dread your period, talk with your doctor. There are many effective treatments for menorrhagia.
The difference between bronchitis and pneumonia is that bronchitis causes an inflammation of the air passages while pneumonia causes fluid in the lungs due to an infection. The common cold however, allows people to remain active and presents itself with a clear runny nose, cough, and a low-grade or no fever.
Factitious disorder is the term used to describe a pattern of behavior centered on the exaggeration or outright falsifications of one’s own health problems or the health problems of others. Some people with this disorder fake or exaggerate physical problems; others fake or exaggerate psychological problems or a combination of physical and psychological problems. Factitious disorder differs from a pattern of falsified or exaggerated behavior called malingering. While malingerers make their claims out of a motivation for personal gain, people with factitious disorder have no such motivation.
Slicosis is caused by inhalation of unbound (free) crystalline silica dust and is characterized by nodular pulmonary fibrosis. Chronic silicosis initially causes no symptoms or only mild dyspnea but over years can advance to involve most of the lung and cause dyspnea, hypoxemia, pulmonary hypertension, and respiratory impairment. Diagnosis is based on history and chest x-ray findings. No effective treatment exists except supportive care and, for severe cases, lung transplantation.
Here are 10 lifestyle changes you can make to lower your blood pressure and keep it down. Lose extra pounds and watch your waistline. Blood pressure often increases as weight increases. ... Exercise regularly. ... Eat a healthy diet. ... Reduce sodium in your diet. ... Limit the amount of alcohol you drink.
Before deciding how to treat one episode of high blood glucose, it is important to figure out why the number is high. Some possible causes include eating a heavy meal, not getting enough physical activity, forgetting to take diabetes medication, and dealing with illness and stress. Insulin is the medication that will bring blood glucose down the fastest. Someone who uses mealtime insulin can take correction doses to lower blood glucose. This requires a thorough understanding of when to inject, how often to give correction doses, and how much insulin to use. You will need to work with your doctor or diabetes educator to learn how to do this. Apart from administering insulin, the fastest way to lower your blood glucose is to engage in physical activity. Exercise results in an increased sensitivity to insulin. It causes your muscle cells to take up more glucose, leaving less of it to circulate in your bloodstream during and after the physical activity (which means a lower blood glucose when you test). Frequent, regular exercise is very important to good blood glucose control no matter what type of diabetes you have. Research has shown that it is vital in warding off long-term complications like neuropathy, retinopathy, and heart and kidney diseases. Don't forget to check with a doctor, though, before making any major changes to your exercise routine. And, if you have type 1 diabetes and your glucose is 250 mg/dl or higher, check for urine ketones. You should not exercise if ketones are present.
Sperm Meets Egg: Weeks 1 to 3 of Pregnancy. Something magical is about to happen! Watch as the ovulation process occurs, and then millions of sperm swim upstream on a quest to fertilize an egg. ... The egg travels down the fallopian tube, pushed by tiny hairs and awaits the arrival or sperm.