Pursing a career in academic surgery among African American medical students.

BACKGROUND: There are few African American students in medical school, and even fewer are choosing academic surgical careers. The objective of this study is to provide insight into what barriers URM students perceive when considering a career in academic surgery. METHODS: This qualitative, descriptive study was conducted at the University of Pennsylvania. Sixteen African American students with an interest in surgery were recruited to participate in the study. The outcomes reported are themes of how participants perceive the challenges of pursuing an academic surgical career. RESULTS: Barriers to pursuing a career in academic surgery cited by students included lifestyle concerns, financial pressures, having to work in a predominantly white environment, lack of mentorship, feelings of having to prove oneself, stressful environments and concerns of being a minority female in surgery. CONCLUSIONS: These study findings indicate that the persistent dearth of African-Americans in academic surgery is likely multi-factorial. Some ways surgical leadership can begin addressing these issues is through establishment of formal mentorship programs, ensuring non-discriminatory recruiting processes, having explicit goals of improving diversity and supporting pipeline programs.

Early rehospitalization after kidney transplantation: assessing preventability and prognosis.

Early rehospitalization after kidney transplantation (KT) is common and may predict future adverse outcomes. Previous studies using claims data have been limited in identifying preventable rehospitalizations. We assembled a cohort of 753 adults at our institution undergoing KT from January 1, 2003 to December 31, 2007. Two physicians independently reviewed medical records of 237 patients (32%) with early rehospitalization and identified (1) primary reason for and (2) preventability of rehospitalization. Mortality and graft failure were ascertained through linkage to the Scientific Registry of Transplant Recipients. Leading reasons for rehospitalization included surgical complications (15%), rejection (14%), volume shifts (11%) and systemic and surgical wound infections (11% and 2.5%). Reviewer agreement on primary reason (85% of cases) was strong (kappa = 0.78). Only 19 rehospitalizations (8%) met preventability criteria. Using logistic regression, weekend discharge (odds ratio [OR] 1.59, p = 0.01), waitlist time (OR 1.10, p = 0.04) and longer initial length of stay (OR 1.42, p = 0.03) were associated with early rehospitalization. Using Cox regression, early rehospitalization was associated with mortality (hazard ratio [HR] 1.55; p = 0.03) but not graft loss (HR 1.33; p = 0.09). Early rehospitalization has diverse causes and presents challenges as a quality metric after KT. These results should be validated prospectively at multiple centers to identify vulnerable patients and modifiable processes-of-care.

Predictors of having a potential live donor: a prospective cohort study of kidney transplant candidates.

The barriers to live donor transplantation are poorly understood. We performed a prospective cohort study of individuals undergoing renal transplant evaluation. Participants completed a questionnaire that assessed clinical characteristics as well as knowledge and beliefs about transplantation. A participant satisfied the primary outcome if anyone contacted the transplant center to be considered as a live donor for that participant. The final cohort comprised 203 transplant candidates, among whom 80 (39.4%) had a potential donor contact the center and 19 (9.4%) underwent live donor transplantation. In multivariable logistic regression, younger candidates (OR 1.65 per 10 fewer years, p < 0.01) and those with annual income >or=US$ 15 000 (OR 4.22, p = 0.03) were more likely to attract a potential live donor. Greater self-efficacy, a measure of the participant's belief in his or her ability to attract a donor, was a predictor of having a potential live donor contact the center (OR 2.73 per point, p < 0.01), while knowledge was not (p = 0.56). The lack of association between knowledge and having a potential donor suggests that more intensive education of transplant candidates will not increase live donor transplantation. On the other hand, self-efficacy may be an important target in designing interventions to help candidates find live donors.

Cell kinetic studies in the murine ventral tongue epithelium: thymidine metabolism studies and circadian rhythm determination.

The oral mucosa is a rapidly replacing body tissue that has received relatively little attention in terms of defining its cell kinetics and cellular organization. The tissue is sensitive to the effects of cytotoxic agents, the consequence of which can be stem cell death with the subsequent development of ulcers and the symptoms of oral mucositis. There is considerable interest in designing strategies to protect oral stem cells and, hence, reduce the mucositis side-effects in cancer therapy patients. Here we present details of a new histometric approach designed to investigate the changing patterns in cellularity in the ventral tongue mucosa. This initial paper in a series of four papers presents observations on the changing patterns in the labelling index following tritiated thymidine administration, which suggest a delayed uptake of tritiated thymidine from a long-term intracellular thymidine pool, a phenomenon that will complicate cell kinetic interpretations in a variety of experimental situations. We also provide data on the changing pattern of mitotic activity through a 24-h period (circadian rhythms). Using vincristine-induced stathmokinesis, the data indicate that 54% of the basal cells divide each day and that there is a high degree of synchrony in mitotic activity with a mitotic peak occurring around 13.00 h. The mitotic circadian peak occurs 9-12 h after the circadian peak in DNA synthesis. The data presented here and in the subsequent papers could be interpreted to indicate that basal cells of BDF1 mice have an average turnover time of about 26-44 h with some cells cycling once a day and others with a 2- or 3-day cell cycle time.

Cell kinetic studies in murine ventral tongue epithelium: cell cycle progression studies using double labelling techniques.

The dorsal and ventral epithelia on the murine tongue exhibit very pronounced circadian rhythms in terms of the cell cycle. These rhythms are such that three injections of tritiated thymidine 3 h apart spanning the circadian peak in S phase cells labelled between 40 and 50% of the basal cells. Injection of bromodeoxyuridine generally gave slightly lower labelling indices. Approximately the same proportion (54% of the basal cells) could be accumulated in metaphase over a 24-h period using vincristine as a stathmokinetic agent. The experiments reported here using mouse ventral tongue epithelium use double-labelling approaches to address the question: what proportion of the approximately 50% of the basal cells that are proliferating have a 24-h cell cycle and can therefore be labelled by a similar labelling protocol the following day? The results suggest a heterogeneity amongst the proliferating basal cells, similar to the heterogeneity proposed for the dorsal tongue epithelium. Although not all the basal component has been accounted for, the data presented here suggest that about 20% of the basal cells may have a cell cycle time of 24 h, about 30% appear to have a longer cell cycle time (48 or 72 h), while about 20% of the basal cells appear to be postmitotic maturing G1 cells, awaiting the appropriate signals for migration into the suprabasal layer.

Cell kinetic studies in the murine ventral tongue epithelium: the effects of repeated exposure to keratinocyte growth factor.

Keratinocyte growth factor (KGF) stimulates proliferation and differentiation in various epithelial systems. Three daily subcutaneous injections of 125 microg of this protein into mice induce dramatic changes in the histology and histometric measurements of the ventral tongue epithelium. The thickness of the epithelium is increased two-fold and the number of cells beneath a 1-mm length of the surface is increased 1.6-fold. KGF also induces a four-fold increase in the number of S phase cells labelled with tritiated thymidine in the basal layer on the third day after KGF administration. The increase in thickness and cellularity persist for at least 4 days after the end of the KGF injections. However, there is a dramatic fall in the number of S phase cells detected by 3HTdR pulse labelling 2 days after the end of the KGF treatment. There are indications that by 7 days after the 3-day regimen of KGF treatment, both thickness and cellularity have fallen back to near control levels. Continued exposure to KGF over a period of 7 days does not result in any further increases in thickness, cellularity or proliferation. In fact, the proliferation decreases on the fifth, sixth and seventh days of KGF injection to control values on day 7. These changes in the epithelium following KGF treatment suggest that the thicker and more cellular epithelium may be more able to cope with an exposure to a cytotoxic agent and hence be protected in comparison with normal or vehicle-treated epithelium.

Cell kinetic studies in the murine ventral tongue epithelium: mucositis induced by radiation and its protection by pretreatment with keratinocyte growth factor (KGF).

Radiation kills or reduces reproductive capacity of proliferating cells, including stem cells. In the oral mucosae this can result in a decline in the number of cells in the tissue which, if severe enough, will result in the formation of an ulcer when the cellularity essentially reaches zero. We have used histometric measurements of cellularity following exposure to radiation in mouse ventral tongue epithelium as a model for oral mucositis (ulcer development). Here we provide further measurements of cellularity changes in the basal layer and in the epithelium as a whole at various times following 15, 20 or 25 Gy doses. The protective effects of prior treatment with keratinocyte growth factor (KGF) are also investigated. 20 Gy of 300 kV X-rays has become our standard reference dose and the changes in cellularity seen following this dose are highly reproducible, with minimum values being observed 6 days following irradiation. A higher dose results in a greater reduction of cellularity, although the minimum value also occurs at 6 days. A lower dose (15 Gy) results in a much shallower curve, with a minimum value being observed about 1 day earlier. These changes in cellularity can be related to the less sensitive index of mucositis, namely epithelial thickness. There is also a sharp peak in proliferation about 1 day after the minimum in cellularity, i.e. on day 7. The peak following a lower dose of radiation occurs a little earlier and, following the higher dose, the peak tends to be broader. Previous work and data presented in the preceding paper in this series has shown that KGF, given over a period of 3 days, results in a dramatic increase in epithelial thickness in oral mucosa, including the ventral tongue. As a result of the increased cellularity induced by KGF given before radiation, a delay in the fall in cellularity results, which is the consequence of the increased number of cells in the epithelium at the beginning of the study.

Epithelial cell proliferative activity and oral cancer progression.

Accurate, predictive assessment of the behaviour and progression of oral cancers and precancers remains elusive in clinical practice. Archival tissue specimens from 10 previously treated patients with oral lesions of known clinical outcome (3 years post-treatment) were re-examined histopathologically, and proliferative cell labelling indices (LIs) determined for Ki67, cyclin A and histone mRNA cell cycle markers. While histone mRNA labelling ultimately proved unreliable, both Ki67 and cyclin A LIs demonstrated a clear trend for enhanced labelling to occur in increasingly dysplastic and neoplastic tissue, with particular emphasis on suprabasal labelling in abnormal tissue. Perhaps of greatest significance was the observation of increased LIs and suprabasal labelling in lesions with poor clinical outcome, such as patients developing recurrent disease or cervical lymph node metastasis. Measurement of cell proliferative activity in individual oral epithelial dysplastic lesions or invasive squamous cell carcinomas may thus provide unique, predictive information on clinical outcome.

The effects of repeated doses of keratinocyte growth factor on cell proliferation in the cellular hierarchy of the crypts of the murine small intestine.

Keratinocyte growth factor (KGF) administered on a daily basis for 3 or more days can result in dramatic changes in tissue architecture, particularly the thickness in oral epithelia, and can afford protection against the cytotoxic effects of radiation on the clonogenic stem cells in the crypts. This protection of intestinal stem cells (increased numbers of surviving crypts) is reflected in an increased survival of animals exposed to a lethal dose of irradiation. The mechanisms underlying these effects are not clear. The present experiments were designed to investigate the nature of any proliferative changes induced in the crypts of the small intestine by protracted exposure to KGF. Tritiated thymidine or bromodeoxyuridine labeling showed statistically significant increases in labeling in the stem cell zone of the crypt, with a concomitant reduction in labeling in the upper regions of the crypt corresponding to the late-dividing transit population. The increase in labeling in the lower regions of the crypt was also observed with Ki-67 staining, but the reduction in the upper regions of the crypt seen with tritiated thymidine was not observed with Ki-67. Metaphase arrest data suggest that the rate of progression through the cell cycle is essentially the same in KGF-treated animals as in controls, but there is a statistically significant increase in the number of mitotic events per crypt. Double labeling studies suggest that, at certain times of the day, there is a greater influx into S phase than efflux. The data overall indicate that KGF induces some complex proliferative changes in the intestinal crypts and are consistent with the hypothesis that the radioprotection may be afforded, at least in part, by a KGF-induced increase in stem cell numbers and/or increases in the number of stem cells in the S phase of the cell cycle. This alteration in the homeostasis of the crypt is compensated for by a foreshortening of the dividing transit lineage.

Toward setting a research agenda for systematic reviews of evidence of the effects of medical education.

PURPOSE: To provide an update on, and a preliminary research agenda for, best evidence medical education (BEME). SUMMARY: Efforts related to evidence-based medical education are summarized briefly, including BEME, the newly formed Campbell Collaboration, and the Cochrane Collaboration's Effective Practice and Organization of Care review group. A list of topics and priorities for which evidence of effectiveness in medical education should be systematically reviewed is provided based on the results of a session at the July 2000 annual meeting of the Society of Directors of Research in Medical Education. The highest ranked topics clustered around four major conceptual areas: (a) curricular design, (b) learning and instructional methods, (c) testing and assessment, and (d) outcomes. CONCLUSIONS: BEME is gaining momentum with growing numbers of people becoming involved as well as an increased number of pertinent workshops, publications, and Web sites. The work of creating pertinent systematic reviews of the medical education literature is at hand.

Have you had your feedback today?

Feedback is an essential component of medical education and adult learning; however, there are several challenges inherent in measuring the feedback directed at medical students. The authors describe the use of a daily e-mail questionnaire to gather information from medical students about the feedback they receive.

Two approaches to measuring quality of life in the HIV/AIDS population: HAT-QoL and MOS-HIV.

OBJECTIVES: Reduce the number of HIV/AIDS-Targeted Quality of Life (HAT-QoL) items, assess psychometric performance of the shortened HAT-QoL, and compare psychometric performance of HAT-QoL to that of Medical Outcomes study HIV Health Survey (MOS-HIV). DESIGN/SUBJECTS: Convenience sample of 215 cross-sectionally studied seropositive individuals. METHODS: Subjects completed the HAT-QoL, MOS-HIV, and sociodemographic and disease-specific questions. HAT-QoL and MOS-HIV responses were entered, separately, into principal components analysis (PCA). Results from PCA, internal consistency and correlation assessments were used to aid the item removal process. Dimension characteristics (e.g., score distributions, internal consistency, scaling success rates, intercorrelations, construct validity) were evaluated. RESULTS: PCA of subjects' (80% male; 45% white; 62% gay/bisexual) responses revealed nine previously identified HAT-QoL dimensions. The measure was shortened by removing 12 items. Two HAT-QoL dimensions (HIV mastery and provider trust) had ceiling effects. All internal consistency coefficients were > 0.80, except those for sexual function (0.57) and medication concerns (0.57). HAT-QoL scaling success rates were > 90% for 7 of 9 dimensions, and a majority of dimensions showed minimal to low intercorrelations. Validity assessments indicated consistent, expected relationships (p < or = 0.05) for all dimensions except the medication concerns and provider trust dimensions. PCA indicated five MOS-HIV factors. Six of the 11 previously defined MOS-HIV dimensions--physical, role, social, and cognitive function, pain, and health transition--had substantial ceiling effects. MOS-HIV scaling success rates were > 90% for only 2 out of 8 evaluable dimensions; three dimensions had very low (40-73%) scaling success rates. Most MOS-HIV dimensions were moderately-to-highly intercorrelated. Validity assessments indicated consistent, expected relationships for all MOS-HIV dimensions. CONCLUSIONS: Six dimensions of the shortened HAT-QoL instrument (overall function, disclosure worries, health worries, financial worries, HIV mastery, and life satisfaction) exhibited good psychometric properties, including limited ceiling effects, low dimension intercorrelations, high internal consistency, and evidence for construct validity. All multi-item MOS-HIV dimensions had high internal consistency and all dimensions revealed consistent evidence for construct validity.

Health maintenance organizations and hospital quality for coronary artery bypass surgery.

This study uses hospital discharge data for 1992-1994 to assess differences between HMO and insured non-HMO patients in California and Florida with regard to the quality of the hospitals used for coronary artery bypass graft (CABG) surgery. The authors found that commercially insured HMO patients in California used higher quality hospitals than commercially insured non-HMO patients, controlling for patient distance to the hospital. In contrast, commercially insured HMO and non-HMO patients in Florida were similarly distributed across hospitals of different quality levels, whereas Medicare HMO patients in Florida used lower quality hospitals than patients in the standard Medicare program. The authors conclude that the association between HMO coverage and hospital quality may differ across geographic areas and patient populations, possibly related to the maturity and structure of managed care markets.

In vivo administration of genistein has no effect on small intestinal epithelial proliferation and apoptosis, but a modest effect on clonogen survival.

The soya metabolite genistein possesses anti-proliferative, pro-apoptotic activities in intestinal epithelial cells in vitro and may reduce epithelial cancer incidence. This could involve cell cycle arrest/apoptosis in the proliferative or clonogenic cells. We investigated the effects of genistein on the small intestinal epithelium in vivo. No effect on the number or distribution of proliferative cells in the crypts was detected. Similarly, no change in spontaneous apoptotic cell incidence or the characteristic stem cell apoptotic response following low dose irradiation was observed. Genistein afforded a modest decrease in clonogen radiosensitivity. Hence, using a range of dosing protocols, sub-cutaneous administration of genistein for periods of up to 1 week did not alter intestinal epithelial homeostasis.