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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.
Nasal polyps are linked to allergic rhinitis, asthma, aspirin allergy, sinus infections, acute and chronic infections, something stuck in the nose, and cystic fibrosis. But many times the cause is unknown. Sometimes, people get them before they develop asthma or sinusitis
A unique video confirming the reality of the introduction of a large amount of irrigant or drug solution into unoperated paranasal sinuses. How is the process of filling the paranasal sinuses in real time during the YAMIK procedure! The use of the YAMIK Nasal Catheter opens up incredible possibilities for the treatment of sinusitis in both children and adults.
Ptosis is when the upper eyelid droops over the eye. The eyelid may droop just a little, or so much that it covers the pupil (the black dot at the center of your eye that lets light in). Ptosis can limit or even completely block normal vision. Children and adults can have ptosis. Fortunately, this condition can be treated to improve vision as well as appearance.
The major elements of the cardiac exam include observation, palpation and, most importantly, auscultation (percussion is omitted). As with all other areas of the physical exam, establishing adequate exposure and a quiet environment are critical. Initially, the patient should rest supine with the upper body elevated 30 to 45 degrees. Most exam tables have an adjustable top. If not, use 2 or 3 pillows. Remember that although assessment of pulse and blood pressure are discussed in the vital signs section they are actually important elements of the cardiac exam.
The baby suffered from ectopia cordis, a rare condition where a baby's heart is located either partially or totally outside the chest. Only 8 out of 1 million babies are born with the condition, and 90 percent of those babies are either stillborn or die within the first three days of life.
Bone is not a static part of the body — it's constantly being resorbed (broken down) and formed throughout your life. Your entire skeleton is replaced about every decade, according to the NIH. During your childhood and teenage years, bone formation occurs more quickly than bone resorption, resulting in growth. You reach your maximum bone density and strength around age 30, after which bone resorption slowly overtakes bone formation. Osteoporosis develops when there's an abnormal imbalance between bone resorption and formation — that is, resorption occurs too quickly, or formation too slowly.
You may have heard that some positions, such as your partner on top (missionary position), are better than others for getting pregnant. In fact, there's no evidence to back these theories up. Experts just haven't done the research yet. What experts have done, though, is use scanning to show what's going on inside when you're doing the deed. The research looked at two positions: the missionary position and doggy style. (Doggy style being when you're on all fours, and your partner enters you from behind). Common sense tells us that these positions allow for deep penetration. This means that they're more likely to place sperm right next to your cervix (the opening of your uterus). The scans confirm that the tip of the penis reaches the areas between the cervix and vaginal walls in both of these positions. The missionary position allows the penis to reach the area at the front of the cervix. The rear entry position reaches the area at back of the cervix. It's amazing what some experts spend their time doing, isn't it! Other positions, such as standing up, or woman on top, may be just as good for getting sperm right next to the cervix. We just don't know yet. So, in the meantime, enjoy some variety in your sex life and keep it fun while you're trying for a baby. And talk to others who are hoping to get pregnant by joining our Actively trying group. Do I have to have an orgasm to conceive? Obviously, it's very important for your partner to reach orgasm if you are trying for a baby. There is no evidence, however, that you need to orgasm to conceive. The female orgasm is all about pleasure and satisfaction. It doesn't really help to get the sperm to the egg. Gentle contractions in your uterus can help the sperm along, but these happen without you having an orgasm. So, it's really not vital for you to reach orgasm after your partner, or even to reach orgasm at all, for you to conceive.
The fuel for the process leading to orgasm is testosterone, a hormone produced in steady supply by the testicles. The testicles also make millions of sperm each day, which mature and then are mixed with whitish, protein-rich fluids. These fluids nourish and support the sperm so they can live after ejaculation for a limited time. This mixture of fluid and sperm, known as semen, is what is moved through the urethra and out the penis during orgasm.