A method for real-time, evidence-based general medical attending rounds.

PURPOSE: To assess the utility and practicality of an evidence-based format in internal medicine attending rounds. METHOD: Two randomly selected teams of residents and medical students in the internal medicine program at the Montefiore Medical Center participated in "Evidence-Based Medicine Attending Month." The process entailed the development of patient-based, searchable questions, a search for the evidence, the critical appraisal of the retrieved literature, and the application of the evidence to the care of the patient. At the last meeting, participants evaluated each case by answering three questions about whether the process (1) had changed the medical management of the patient during the admission, (2) had changed the way they would manage similar patients in the future, and (3) had informed them about the disease process in general. RESULTS: A total of 12 of 16 formal EBM questions were developed and assessed (75% completion rate) during the four-week period, in addition to the standard background literature reviews usually performed. Twenty-two articles were retrieved and critically appraised. The evaluation demonstrated that 50% of the participants felt the process had changed the active management of patients currently treated by the team, 75% reported that the process would affect the care of future patients with comparable medical problems, and over 90% believed the program had informed them about the disease process. CONCLUSIONS: The formal EBM approach was conveniently implemented and enhanced the learning experience of the participants. It helped inform students' and residents' patient care at the time and their attitudes towards future patients. Hence, it is both practical and useful to perform formal EBM attending rounds.     

Optimizing oral vaccines: induction of systemic and mucosal B-cell and antibody responses to tetanus toxoid by use of cholera toxin as an adjuvant.

Cholera toxin (CT) is an effective mucosal antigen and acts as an adjuvant when given orally with various antigens; however, few studies have compared the levels of antibody responses to CT and coadministered protein in systemic and mucosal tissues. In this study, we used tetanus toxoid (TT) for assessment of immune responses. Time course and dose-response studies established that 250 micrograms of TT given orally with 10 micrograms of CT three times at weekly intervals induced high serum and gastrointestinal tract anti-TT and anti-CT antibody responses. Oral immunization with TT alone induced no detectable mucosal immunoglobulin A (IgA) antibodies in fecal extracts and only weak serum IgG anti-TT responses. The coadministration of CT and TT induced peak serum IgG anti-TT responses following two oral doses that remained constant after the third oral immunization, while optimal mucosal IgA responses were seen after the third oral immunization. The serum anti-TT response obtained with CT and TT proved protective against TT challenge (100 minimum lethal doses), whereas mice orally given CT or TT alone died. Antigen-specific B-cell responses were assessed with an isotype-specific Elispot assay of isolated lymphoid cells from the spleen, Peyer's patches, and the small intestinal lamina propria. Interestingly, approximately fourfold-higher numbers of IgA anti-CT than of anti-TT antibody-producing (spot-forming) cells occurred in lymphocytes from the lamina propria of mice orally immunized with both TT and CT. The adjuvant CT did not induce polyclonal B-cell responses in mice given CT by the oral route, since no significant differences in total numbers of B cells producing IgA, IgG, or IgM were found compared with the numbers in mice given TT alone. The results clearly indicate that serum and mucosal antibody responses develop with different kinetics and that protective TT-specific antibody responses are generated in the systemic compartment when TT is administered with CT via the oral route.     

Neural tube malformations: complex segregation analysis and calculation of recurrence risks.

Familial data on neural tube malformations in Great Britain were submitted to segregation analysis under the mixed model. Maternal and fetal factors cannot be discriminated in the absence of substantial bodies of data on spina bifida survivors who reproduce or on half-sibs. Early abortion studies would allow differential mortality in utero to be taken into account. After fitting the mixed and generalised single locus models, it is concluded that the multifactorial model can provisionally be used for calculation of recurrence risks. Pathogenic hypotheses implicating twinning seem to rest on little evidence.     

Processing of radical prostatectomy specimens for correlation of data from histopathological, molecular biological, and radiological studies: a new whole organ technique

AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices.     

Factors influencing the psychological impact of prolonged unemployment and of re-employment

Six hundred and twenty-nine unemployed men were re-interviewed 9 months after initial measurement of their psychological health and commitment to the labour market. For those men remaining continuously unemployed between interviews, no further decrement was observed in mean General Health Questionnaire scores after 3 months without a job, but a significant deterioration was recorded for the sub-sample initially unemployed for less than 3 months. Small but significant declines were observed after 3 months on a single-item measure of reported health and on an 8-item index of commitment to the labour market. For those regaining paid work, all measures of health showed large improvements, and employment commitment was unchanged. Multiple regression analyses were used to examine factors associated with magnitude of changes during continuous unemployment, yielding a systematic pattern of significant relationships. For example, higher employment commitment at initial interview was significantly associated with a greater subsequent decline in psychological health, but not in physical health; reporting a chronic health impairment at initial interview was significantly associated with a greater subsequent decrement in physical health, but not in psychological health.     

Exercise and skeletal muscle ageing: cellular and molecular mechanisms

As we age, our skeletal muscle becomes smaller and weaker. In addition, the remaining muscle is more susceptible to damage, particularly following exercise, recovery from damage is severely impaired and muscle is unable to adapt rapidly following sequential periods of exercise. The mechanisms by which skeletal muscle damage occurs are poorly understood and the role that an increased production of free radical species plays in this damage is controversial. However, evidence is emerging which suggests that an increased production of free radicals may act as an activator of the adaptive response in skeletal muscle, resulting in the increased production of antioxidant enzymes and heat shock proteins (HSPs). The increased content of these proteins facilitates rapid remodelling of muscle and provides considerable protection against subsequent periods of damaging exercise. There is considerable evidence that the production of free radicals is modified during the ageing process. The aim of this review is to examine the possible effects of this modification on the ability of muscle cells to respond to stress and the functional effect that this may have on our muscles as we age.     

Characterization of murine monoclonal antibodies to Escherichia coli J5.

Results show that various inbred strains of mice can be segregated into two distinct groups, based on their capacity to allow a number of nontuberculous mycobacterial infections to grow in target organs following experimental intravenous infection. The first group, which allowed these infections to grow progressively, was thus designated as naturally susceptible to these infections; in contrast, those strains which were able to exert detectable bacteriostasis were designated as naturally resistant. It was then found that segregation of mouse strains based on this distinction also mirrored the capacity of these animals to generate acquired immunity to the mycobacterial infections. For example, Mycobacterium simiae grew progressively in susceptible C57BL/6 mice, subsequently triggering acquired mechanisms of immunity, whereas no evidence for acquired immunity could be found in resistant A/Tru mice infected with this organism. The possibility that acquired immunity could not be expressed in the latter strain as a result of a defect in macrophage activation was excluded. Moreover, it was found that the trait of resistance to these infections could be transferred by bone marrow cells into radiation chimeras, thus indicating that this trait was expressed by the progeny of hemopoietic precursor cells. Subsequent backcross analysis to determine the mode of inheritance of the trait of resistance to these mycobacterial infections revealed data that were consistent with the hypothesis that this resistance is controlled by more than one gene. Statistical analysis of the data by the maximum likelihood method suggested polygenic control, although in some cases the probability values suggested control by a major gene, influenced by modifier genes. These findings suggest that the previous hypothesis that the growth of mycobacterial infections in inbred strains of mice is controlled by a single gene should be reevaluated.     

Detection of human immunodeficiency virus type 1 (HIV-1) DNA and RNA sequences in HIV-1 antibody-positive blood donors in Uganda by the Roche AMPLICOR assay.

The ability of commercially available PCR-based assays to accurately detect or quantitate human immunodeficiency virus type 1 (HIV-1) DNA or RNA in individuals predominantly infected with HIV-1 subtypes A and D is not known. Therefore, peripheral leukocytes from 43 individuals in Kampala, Uganda, positive for HIV by the Western blot (immunoblot) assay were tested by using the Roche AMPLICOR HIV-1 assay for the detection of DNA gag sequences. Plasma from these same individuals was tested by using the Roche HIV-1 AMPLICOR MONITOR HIV-1 assay for the quantitation of HIV-1 RNA gag sequences. In addition, peripheral leukocytes were tested for HIV-1 DNA by using a lower annealing temperature or a different primer pair for the HIV-1 pol region. The proportions of individuals with detectable HIV-1 DNA and RNA gag sequences by the Roche assays were 74 and 90%, respectively. The proportions positive for HIV-1 DNA sequences by using a 50 degrees C annealing temperature or the pol primer pair were 71 and 98%, respectively. In summary, the standard Roche assay did not detect HIV-1 DNA sequences in a significant number of HIV-1-infected individuals in Uganda. However, use of a pol primer pair increased the sensitivity of the assay to 98%. The sensitivity of the Roche AMPLICOR MONITOR assay for the detection and quantitation of HIV-1 RNA sequences was significantly higher than that of the DNA-based assay, but the efficiency of the assay, and hence, the accuracy of the values obtained with RNA, is not known. Modifications to existing assays are needed to enhance the sensitivities and accuracies of these commercially available assays for use in developing countries where non-B HIV-1 subtypes predominate.     

Detection of Shiga toxin-producing Shigella dysenteriae type 1 and Escherichia coli by using polymerase chain reaction with incorporation of digoxigenin-11-dUTP.

A technique has been developed for the detection of Shiga toxin- and Shiga-like toxin type I (ShT/SLT-I)-producing Shigella dysenteriae type 1 and Escherichia coli by using the polymerase chain reaction with the incorporation of digoxigenin-11-dUTP. Target DNA liberated from whole cells was amplified, using primer pairs homologous to the A-subunit genes of ShT/SLT-I. The TTP analog digoxigenin-11-dUTP was incorporated into the reaction mixture, permitting nonradioactive labeling of the amplified DNA. The labeled polymerase chain reaction products were hybridized to specific gene sequences immobilized on a nitrocellulose membrane and detected by using an alkaline phosphatase-conjugated antibody to digoxigenin and the enzyme substrates. Toxin-producing strains of E. coli and S. dysenteriae type 1 were identified as colored spots on the membrane. Because this technique does not require DNA purification, gel electrophoresis, or radioactive DNA probes, it is suitable for the clinical detection of ShT/SLT-I-producing strains of S. dysenteriae type 1 and E. coli.     

Insights into the ethnic differences in serum ferritin between black and white US adult men

Although higher serum ferritin (SF) concentrations have been consistently observed among blacks, despite their lower hemoglobin (Hb) concentrations compared with whites, few studies attempted to explain this SF difference. To determine the possible factors contributing to the observed SF difference between blacks and whites, 1,938 non‐Hispanic white (NHW) and 1,616 non‐Hispanic black (NHB) male subjects, aged 20–65 years were selected from the third National Health and Nutrition Examination Survey (NHANES III). Multiple regression analysis was used to examine the contribution of dietary, biochemical, and socioeconomic variables to the observed SF difference between the two groups. NHB subjects showed a continuing, significantly higher SF concentration compared with NHW subjects at each age group. Age, serum total protein, mean cell volume (MCV), and γ glutamyl transferase (GGT) were positively associated with SF, whereas percent energy from carbohydrate and fat, calcium intake, serum α‐carotene, and iron binding capacity (TIBC) were inversely associated with SF (P < 0.01). After excluding subjects with abnormal serum total protein, TIBC and GGT levels from the analysis (the final regression model), the SF difference dropped to 3.95 μg/l (initial difference = 37.1 μg/l) between NHWs and NHBs. The results suggest that the oft‐noted black‐white SF difference is a result of factors including overall nutrition and health, iron status, and hepatic well‐being. Higher SF, low Hb, and reduced TIBC level observed in blacks are consistent with the definition of anemia of chronic disease (ACD). Future investigations are needed to confirm the role of ACD in the black–white SF difference. Am. J. Hum. Biol., 2008. © 2008 Wiley‐Liss, Inc.