Emerging issues in infective endocarditis. (33/196)

Infective endocarditis, a serious infection of the endocardium of the heart, particularly the heart valves, is associated with a high degree of illness and death. It generally occurs in patients with altered and abnormal heart architecture, in combination with exposure to bacteria through trauma and other potentially high-risk activities involving transient bacteremia. Knowledge about the origins of endocarditis stems from the work of Fernel in the early 1500s, and yet this infection still presents physicians with major diagnostic and management dilemmas. Endocarditis is caused by a variety of bacteria and fungi, as well as emerging infectious agents, including Tropheryma whiplei, Bartonella spp., and Rickettsia spp. We review the evolution of endocarditis and compare its progression with discoveries in microbiology, science, and medicine.  (+info)

Do favorite movie stars influence adolescent smoking initiation? (34/196)

OBJECTIVES: We sought to determine whether adolescents whose favorite movie stars smoke on-screen are at increased risk of tobacco use. METHODS: During interviews, adolescent never smokers taking part in the California Tobacco Survey nominated their favorite stars. We reviewed popular films released during 1994 through 1996 to determine whether stars smoked on-screen in at least 2 films. RESULTS: One third of never smokers nominated a star who smoked on-screen, which independently predicted later smoking risk (odds ratio [OR] = 1.36; 95% confidence interval [CI] = 1.02, 1.82). The effect was strong among girls (OR = 1.86; 95% CI = 1.26, 2.73). Among boys, there was no independent effect after control for receptivity to tobacco industry promotions. CONCLUSIONS: Public health efforts to reduce adolescent smoking must confront smoking in films as a tobacco marketing strategy.  (+info)

Xanthelasma and lipoma in Leonardo da Vinci's Mona Lisa. (35/196)

The painting Mona Lisa in the Louvre, Paris, by Leonardo da Vinci (1503-1506), shows skin alterations at the inner end of the left upper eyelid similar to xanthelasma, and a swelling of the dorsum of the right hand suggestive of a subcutaneous lipoma. These findings in a 25-30 year old woman, who died at the age of 37, may be indicative of essential hyperlipidemia, a strong risk factor for ischemic heart disease in middle age. As far as is known, this portrait of Mona Lisa painted in 1506 is the first evidence that xanthelasma and lipoma were prevalent in the sixteenth century, long before the first description by Addison and Gall in 1851.  (+info)

The effects of very early Alzheimer's disease on the characteristics of writing by a renowned author. (36/196)

Iris Murdoch (I.M.) was among the most celebrated British writers of the post-war era. Her final novel, however, received a less than enthusiastic critical response on its publication in 1995. Not long afterwards, I.M. began to show signs of insidious cognitive decline, and received a diagnosis of Alzheimer's disease, which was confirmed histologically after her death in 1999. Anecdotal evidence, as well as the natural history of the condition, would suggest that the changes of Alzheimer's disease were already established in I.M. while she was writing her final work. The end product was unlikely, however, to have been influenced by the compensatory use of dictionaries or thesauri, let alone by later editorial interference. These facts present a unique opportunity to examine the effects of the early stages of Alzheimer's disease on spontaneous written output from an individual with exceptional expertise in this area. Techniques of automated textual analysis were used to obtain detailed comparisons among three of her novels: her first published work, a work written during the prime of her creative life and the final novel. Whilst there were few disparities at the levels of overall structure and syntax, measures of lexical diversity and the lexical characteristics of these three texts varied markedly and in a consistent fashion. This unique set of findings is discussed in the context of the debate as to whether syntax and semantics decline separately or in parallel in patients with Alzheimer's disease.  (+info)

A day of great illumination: B. F. Skinner's discovery of shaping. (37/196)

Despite the seminal studies of response differentiation by the method of successive approximation detailed in chapter 8 of The Behavior of Organisms (1938), B. F. Skinner never actually shaped an operant response by hand until a memorable incident of startling serendipity on the top floor of a flour mill in Minneapolis in 1943. That occasion appears to have been a genuine eureka experience for Skinner, causing him to appreciate as never before the significance of reinforcement mediated by biological connections with the animate social environment, as opposed to purely mechanical connections with the inanimate physical environment. This insight stimulated him to coin a new term (shaping), and also led directly to a shift in his perspective on verbal behavior from an emphasis on antecedents and molecular topographical details to an emphasis on consequences and more molar, functional properties in which the social dyad inherent to the shaping process became the definitive property of verbal behavior. Moreover, the insight seems to have emboldened Skinner to explore the greater implications of his behaviorism for human behavior writ large, an enterprise that characterized the bulk of his post-World War II scholarship.  (+info)

Steps and pips in the history of the cumulative recorder. (38/196)

From its inception in the 1930s until very recent times, the cumulative recorder was the most widely used measurement instrument in the experimental analysis of behavior. It was an essential instrument in the discovery and analysis of schedules of reinforcement, providing the first real-time analysis of operant response rates and patterns. This review traces the evolution of the cumulative recorder from Skinner's early modified kymographs through various models developed by Skinner and his colleagues to its perfection in the 1950s, and then into the 1960s when it proliferated as different scientific instrument companies began marketing their own models of the cumulative recorder. With the rise of digital computers, the demise of the cumulative recorder as a scientific instrument was inevitable; however, the value of the cumulative record as a monitoring device to assess schedule control of behavior continues. The cumulative recorder remains, along with the operant conditioning chamber, an icon of Skinner's approach to psychology.  (+info)

Darwin's illness revealed. (39/196)

After returning from the Beagle in 1836, Charles Darwin suffered for over 40 years from long bouts of vomiting, gut pain, headaches, severe tiredness, skin problems, and depression. Twenty doctors failed to treat him. Many books and papers have explained Darwin's mystery illness as organic or psychosomatic, including arsenic poisoning, Chagas' disease, multiple allergy, hypochondria, or bereavement syndrome. None stand up to full scrutiny. His medical history shows he had an organic problem, exacerbated by depression. Here we show that all Darwin's symptoms match systemic lactose intolerance. Vomiting and gut problems showed up two to three hours after a meal, the time it takes for lactose to reach the large intestine. His family history shows a major inherited component, as with genetically predisposed hypolactasia. Darwin only got better when, by chance, he stopped taking milk and cream. Darwin's illness highlights something else he missed--the importance of lactose in mammalian and human evolution.  (+info)

Celebrity endorsements of cancer screening. (40/196)

Celebrities often promote cancer screening by relating personal anecdotes about their own diagnosis or that of a loved one. We used data obtained from a random-digit dialing survey conducted in the United States from December 2001 through July 2002 to examine the extent to which adults of screening age without a history of cancer had seen or heard or been influenced by celebrity endorsements of screening mammography, prostate-specific antigen (PSA) testing, or sigmoidoscopy or colonoscopy. The survey response rate was 72% among those known to be eligible and 51% among potentially eligible people accounting for those who could not be contacted. A total of 360 women aged 40 years or older and 140 men aged 50 years or older participated in the survey. Most respondents reported they "had seen or heard a celebrity talk about" mammography (73% of women aged 40 years or older), PSA testing (63% of men aged 50 years or older), or sigmoidoscopy or colonoscopy (52% of adults aged 50 years or older). At least one-fourth of respondents who had seen or heard a celebrity endorsement said that the endorsement made them more likely to undergo mammography (25%), PSA testing (31%), or sigmoidoscopy or colonoscopy (37%).  (+info)