Mycobacterium avium invades the intestinal mucosa primarily by interacting with enterocytes

Previous studies have demonstrated that Mycobacterium avium can invade intestinal epithelial cells both in vitro and in vivo. When given to mice orally, M. avium preferentially interacts with the intestinal mucosa at the terminal ileum. We evaluated the mechanism(s) of M. avium binding and invasion of the intestinal mucosa using three different systems: (i) electron microscopy following administration of M. avium into an intestinal loop in mice, (ii) quantitative comparison of the bacterial load in Peyer's patch areas of the terminal ileum versus areas that do not contain Peyer's patches, and (iii) investigation of the ability of M. avium to cause disseminated infection following oral administration using B-cell-deficient mice, lacking Peyer's patches, in comparison with C57BL/6 black mice. By all approaches, M. avium was found to invade the intestinal mucosa by interacting primarily with enterocytes and not with M cells.     

Self-reported symptoms in healthy young adults to predict potential coronavirus disease 2019

ObjectiveTo assess the utility of self-reported symptoms in identifying positive coronavirus disease 2019 (COVID-19) cases among predominantly healthy young adults in a military setting.MethodsA questionnaire regarding COVID-19 symptoms and exposure history was administered to all individuals contacting the Israeli Defence Forces Corona call-centre, before PCR testing. Surveyed symptoms included cough, fever, sore throat, rhinorrhoea, loss of taste or smell, chest pain and gastrointestinal symptoms. Factors were compared between positive and negative cases based on confirmatory test results, and positive likelihood ratios (LR) were calculated. Results were stratified by sex, body mass index, previous medical history and dates of questioning, and a multivariable analysis for association with positive test was conducted.ResultsOf 24 362 respondents, 59.1% were men with a median age of 20.5 years (interquartile range 19.6–22.4 years). Significant positive LRs were associated with loss of taste or smell (LR 3.38, 95% CI 3.01–3.79), suspected exposure (LR 1.33, 95% CI 1.28–1.39) and fever (LR 1.26, 95% CI 1.17–1.36). Those factors were also associated with positive PCR result in a multivariable analysis (OR 3.51, 95% CI 3.04–4.06; OR 1.86, 95% CI 1.65–2.09; and OR 1.34, 95% CI 1.19–1.51, respectively). Reports of loss of taste or smell increased gradually over time and were significantly more frequent during the late period of the study (63/5231, 1.21%; 156/7941, 1.96%; and 1505/11 190, 13.45%: p < 0.001).ConclusionLoss of taste or smell, report of a suspicious exposure and fever (>37.5°C) were consistently associated with positive LRs for a positive SARS-CoV-2 PCR test result, in a population of predominantly young and healthy adults.     

Treatment of acute rheumatic fever and acute rheumatic heart disease

The treatment of acute rheumatic fever and acute rheumatic heart disease with failure was discussed in this morning's seminar. The efficacy of chemotherapy in the prevention of rheumatic recurrences was questioned. Massive salicylate therapy for acute rheumatic fever was considered effective in changing the course of rheumatic polyarthritis and early carditis. The benefits derived from sanatorium type of care for the protracted case of rheumatic disease were described and the principles underlying the aims of this type of care were delineated. Digitalis in the treatment of acute rheumatic carditis with failure was considered of limited value. Finally, the use of high concentrations of oxygen in the treatment of acute carditis was discussed. It was pointed out that while oxygen therapy may not influence the duration of rheumatic activity, it seems to lessen the cardiac disability resulting from carditis. Some of the physiologic principles responsible for the salutory effects of oxygen therapy were presented.     

The role of visual attention in dyslexia: Behavioral and neurobiological evidence

Poor phonological processing has typically been considered the main cause of dyslexia. However, visuo‐attentional processing abnormalities have been described as well. The goal of the present study was to determine the involvement of visual attention during fluent reading in children with dyslexia and typical readers. Here, 75 children (8–12 years old; 36 typical readers, 39 children with dyslexia) completed cognitive and reading assessments. Neuroimaging data were acquired while children performed a fluent reading task with (a) a condition where the text remained on the screen (Still) versus (b) a condition in which the letters were being deleted (Deleted). Cognitive assessment data analysis revealed that visual attention, executive functions, and phonological awareness significantly contributed to reading comprehension in both groups. A seed‐to‐voxel functional connectivity analysis was performed on the fluency functional magnetic resonance imaging task. Typical readers showed greater functional connectivity between the dorsal attention network and the left angular gyrus while performing the Still and Deleted reading tasks versus children with dyslexia. Higher connectivity values were associated with higher reading comprehension. The control group showed increased functional connectivity between the ventral attention network and the fronto‐parietal network during the Deleted text condition (compared with the Still condition). Children with dyslexia did not display this pattern. The results suggest that the synchronized activity of executive, visual attention, and reading‐related networks is a pattern of functional integration which children with dyslexia fail to achieve. The present evidence points toward a critical role of visual attention in dyslexia.     

Ultrastructural study of Mycobacterium avium infection of HT-29 human intestinal epithelial cells

Mycobacterium avium is a common pathogen in AIDS patients and, in a large percentage of those patients, M. avium infection appears to be acquired via the gastrointestinal tract. M. avium is able to bind to and enter human and murine intestinal epithelial cells in vitro and in vivo. The invasion by and intracellular fate of M. avium in the HT-29 intestinal epithelial cell line was examined in an ultrastructural study. Bacterial contact with polarised cells was observed 10-15 min after monolayer infection and in polarised monolayers this always occurred in areas lacking microvilli. Contact with HT-29 cells did not appear to take place in a preferential area on the bacterial cell. Following invasion, M. avium was encountered within vacuoles containing either single or multiple bacteria; the latter evolved to contain only an individual bacterium. Vacuoles containing more than one bacterium were seen early in the infection and eventually underwent segmentation, with each bacterium occupying a vacuole. No bacteria were observed outside vacuoles up to 5 days after infection.     

Clinician Use of a Palmtop Drug Reference Guide

Objective: Problems involving drug knowledge are one of the most common causes of serious medication errors. Although the information that clinicians need is often available somewhere, retrieving it expeditiously has been problematic. At the same time, clinicians are faced with an ever-expanding pharmacology knowledge base. Recently, point-of-care technology has become more widely available and more practical with the advent of handheld, or palmtop, computing. Therefore, the authors evaluated the clinical contribution of a drug database developed for the handheld computer. ePocrates Rx (formerly known as qRx; ePocrates, San Carlos, California) is a comprehensive drug information guide that is downloadable free from the Internet and designed for the Palm OS platform align="right".Design: A seven-day online survey of 3,000 randomly selected ePocrates Rx users was conducted during March 2000.Measurements: User technology experience, product evaluation and usage patterns, and the effects of the drug reference database on information-seeking behavior, practice efficiency, decision making, and patient care.Results: The survey response rate was 32 percent (n=946). Physicians reported that ePocrates Rx saves time during information retrieval, is easily incorporated into their usual workflow, and improves drug-related decision making. They also felt that it reduced the rate of preventable adverse drug events.Conclusions: Self-reported perceptions by responding clinicians endorse improved access to drug information and improved practice efficiency associated with the use of handheld devices. The clinical and practical value of using these devices in clinical settings will clearly grow further as wireless communication becomes more ubiquitous and as more applications become available.Medical knowledge is growing exponentially,¹ especially in the field of therapeutics. Pharmacologic advances have resulted in an ever-increasing variety of medications for clinicians to employ in patient care. Medications frequently have complex dosing regimens, changing indications, unique contraindications, and multiple drug–drug interactions and can cause serious adverse reactions. Because of the limitations of human memory,^2,3 it has become increasingly difficult for clinicians to keep up to date on the prescribing requirements of drugs, especially recently approved drugs.⁴Inquiries about drugs are one of the most frequent questions that clinicians have.⁵ This makes point-of -care technology—which can provide prescribing information at the bedside, on the hospital ward, and in the office examining room—especially attractive.⁶ Such technology has the potential to reduce the information search times of physicians, and such access may reduce the likelihood of incorrect and harmful drug-prescribing behavior.⁷Adverse drug events (ADEs), or injuries due to drugs, are frequent in a variety of patient care settings. Many are preventable and may be associated with significant patient injury.^8–11 Data suggest that drug knowledge deficiencies are the single most common systems cause of serious medication errors in inpatients.¹² Recent publicity has encouraged public and private support for patient safety improvements, including building safer medication practices.^10,11,13Several drug reference guides designed for use on handheld, or palmtop, computers have recently become commercially available, including ePocrates Rx (formerly known as qRx; ePocrates, San Carlos, California), a comprehensive drug information application. We sought to survey physician users to assess their experience incorporating handheld electronic drug reference guides into routine patient care.