Nitrogen-containing bisphosphonates inhibit the mevalonate pathway and prevent post-translational prenylation of GTP-binding proteins, including Ras

Bisphosphonates are currently the most important class of antiresorptive drugs used for the treatment of metabolic bone diseases. Although the molecular targets of bisphosphonates have not been identified, these compounds inhibit bone resorption by mechanisms that can lead to osteoclast apoptosis. Bisphosphonates also induce apoptosis in mouse J774 macrophages in vitro, probably by the same mechanisms that lead to osteoclast apoptosis. We have found that, in J774 macrophages, nitrogen-containing bisphosphonates (such as alendronate, ibandronate, and risedronate) inhibit post-translational modification (prenylation) of proteins, including the GTP-binding protein Ras, with farnesyl or geranylgeranyl isoprenoid groups. Clodronate did not inhibit protein prenylation. Mevastatin, an inhibitor of 3-hydroxy-3-methylglutatyl (HMG)-CoA reductase and hence the biosynthetic pathway required for the production of farnesyl pyrophosphate and geranylgeranyl pyrophosphate, also caused apoptosis in J774 macrophages and murine osteoclasts in vitro. Furthermore, alendronate-induced apoptosis, like mevastatin-induced apoptosis, could be suppressed in J774 cells by the addition of farnesyl pyrophosphate or geranylgeranyl pyrophosphate, while the effect of alendronate on osteoclast number and bone resorption in murine calvariae in vitro could be overcome by the addition of mevalonic acid. These observations suggest that nitrogen-containing bisphosphonate drugs cause apoptosis following inhibition of post-translational prenylation of proteins such as Ras. It is likely that these potent antiresorptive bisphosphonates also inhibit bone resorption by preventing protein prenylation in osteoclasts and that enzymes of the mevalonate pathway or prenyl protein transferases are the molecular targets of the nitrogen-containing bisphosphonates. Furthermore, the data support the view that clodronate acts by a different mechanism.

Factors determining outcome for breast-conserving irradiation with margin-directed dose escalation to the tumor bed

PURPOSE

A prospectively applied treatment policy for breast-conserving therapy used margin assessment as the exclusive guide to the intensity of therapy directed at the tumor-bearing quadrant.

METHODS AND MATERIALS

From 1982-1994, there were 509 treated Stage I and II breast carcinomas with a median follow-up of 72 months. For operational purposes, tumor excision margins were prospectively defined as: > 5 mm, 2.1-5 mm, > 0 < or = 2 mm, and positive. If a margin was assessed as < or = 2 mm or indeterminate, and it was deemed cosmetically feasible, a reexcision of the tumor bed would be performed. All patients received whole breast irradiation to 50-50.4 Gy. The following scheme for tumor bed boost irradiation as a function of final margin status (FMS) was observed: (a) Minimal risk = no tumor found on reexcision, no boost performed; (b) low risk = FMS > 5 mm, boost of 10 Gy; intermediate risk = FMS 2.1-5 mm, boost to 14 Gy; high risk = FMS < or = 2 mm or positive, boost to 20 Gy. Cases were analyzed for local failure (LF) with respect to histology (invasive ductal (IDC), IDC with associated DCIS (IDC/DCIS), invasive lobular (ILC)), age, tumor size, total excision volume, reexcision, total dose, tamoxifen therapy, and chemotherapy.

RESULTS

There were 19 breast recurrences for a Kaplan-Meier local failure rate for all cases at 5 and 10 years of 2.7% and 7.1%, respectively. Local failure in the first 4 years of follow-up was rare, with a mean annual incidence rate of 0.25% that rose to a mean of 1.1% in subsequent years. Univariate results of Cox proportional hazards regression survival models found positive FMS (p = 0.02), IDC/DCIS (p = 0.04) and age (0.0006) as significantly associated with local failure. In a multivariable model of FMS and IDC/DCIS, FMS retained significance (p = 0.01) but IDC/DCIS was borderline (p = 0.06). When FMS and age were included in a multivariable model, there was a significant interaction (p = 0.01) between the two variables. There was a significant increase in the relative risk of LF for age < or = 45 years (range 11.1-17.4), irrespective of FMS category. Although excellent overall control rates were achieved for patients > 45 years, for younger patients LF rates appeared to remain proportional to the relative closeness of the FMS, despite rigorous dose escalation.

CONCLUSIONS

Graded tumor-bed dose escalation in response to FMS results in an exceptionally low risk of "early" local recurrence within the first 5 years of follow-up. However, this strategy is unable to completely overcome the longer term adverse influence of young age and positive FMS.

Evaluation of recombinant dengue viral envelope B domain protein antigens for the detection of dengue complex-specific antibodies

To increase the specificity of dengue (DEN) diagnosis based on antibody detection, we have evaluated recombinant proteins as antigens that incorporate most of the B domain of the DEN virus envelope protein fused to the trpE protein of Escherichia coli (trpE-DEN). A pooled antigen consisting of trpE-DEN proteins representing all four serotypes of DEN virus was used in an indirect ELISA for the detection of IgG or IgM antibody. This assay was compared with a standard IgG indirect ELISA and an IgM-capture ELISA using DEN virus-infected cell culture pooled antigens. The results indicated that the trpE-DEN antigens and the cell culture antigens were equally sensitive for detecting IgM and IgG antibodies in convalescent sera from Peru and Indonesia representing virus isolation-confirmed primary and secondary DEN infections, respectively. Fourteen day postinfection IgG antibody-positive sera obtained from individuals infected with DEN-1 virus who had been vaccinated with other flaviviruses were more strongly reactive with the cell culture antigen than with the recombinant antigen, but by day 21 postinfection, a strong antibody response to the trpE-DEN antigens was present. These results suggested that the early antibody response was directed predominantly towards shared flavivirus group antigens that were not detected with the trpE-DEN antigens. Comparison of the trpE-DEN-1 recombinant antigen with a DEN-1 virus-infected cell lysate antigen for the detection of IgG antibody in sera from a cohort of 55 individuals from Peru who seroconverted over a one-year period indicated greater specificity for the recombinant antigens. Also, sera from individuals with no known DEN infections that had been sequentially vaccinated with yellow fever and Japanese encephalitis reacted with the DEN virus cell culture antigen in the IgG ELISA, but did not react with the trpE-DEN pooled antigens. Similarly, YF IgM antibody positive samples that showed cross-reactivity with the DEN virus cell culture antigens, did not react with the trpE-DEN pooled antigens. These results indicated that the trpE-DEN pooled antigen provided a more specific diagnosis of dengue infections than DEN virus-infected cell culture antigen and avoided the biohazards associated with handling live virus during the preparation of diagnostic reagents. The trpE-DEN pooled antigen should permit a better approach to distinguish between past DEN and other flavivirus infections in epidemiologic surveys, and also increase the specificity of serologic diagnosis of acute DEN infections.

Results of the 1997 National Resident Matching Program: family practice

The 1997 National Resident Matching Program (NRMP) results reveal all-time highs for the number of positions filled in family practice residencies (2,905) and the number of positions filled with US seniors (2,340). This is the largest number of US seniors choosing family practice in the history of the NRMP. Of the 65 additional positions filled through the NRMP, compared with 1996 (2,905 versus 2,840), 64 were filled with additional US seniors (2,340 versus 2,276). Continuing a trend begun in 1992, the 1997 results showed more positions filled in family practice residencies on July 1 than in the previous year, with 3,570 in 1997, compared with 3,494 in 1996. Internal medicine residencies matched 128 more US seniors in 1997, and pediatric residencies matched 63 more US seniors. Of the US seniors matching through the NRMP, only 37.5% are predicted to practice as generalists. In the past 5 years, family practice has been the choice of 71.5% of additional US seniors choosing primary care. The continued record increased interest in family practice as a career, coupled with the nation's need for more family physicians, demands increased support for the nation's family practice residency programs.

Entry of US medical school graduates into family practice residencies: 1996-1997 and 3-year summary

BACKGROUND AND OBJECTIVES

This is the 16 report prepared by the American Academy of Family Physicians (AAFP) on the percentage of each US medical school's graduates entering family practice residency programs. Approximately 15.9% of the 16,029 graduates of the US medical schools between July 1995 and June 1996 were first-year family practice residents in October 1996, compared with 14.6% in 1995 and 13.4% in 1994. This is the highest percentage since 1980-1981 (12.8%), when this series of studies began. Medical school graduates from publicly funded medical schools were almost twice as likely to be first-year family practice residents in October 1996 than were residents from privately funded schools, 19.1% compared with 11.2%. The Mountain region reported the highest percentage of medical school graduates who were first-year residents in family practice programs in October 1996 at 24%; the Middle Atlantic and New England regions reported the lowest percentage at 11.4% and 9.9%, respectively. Nearly half of the medical school graduates (48.4%) entering a family practice residency program as first-year residents in October 1996 entered a program in the same state where they graduated from medical school. The percentages for each medical school have varied substantially from year to year since the AAFP began reporting this information. This article reports the average percentage for each medical school for the last 3 years. Also reported are the number and percentage of graduates from colleges of osteopathic medicine who entered Accreditation Council for Graduate Medical Education-accredited family practice residency programs.

Second report of AIDS related attitudes and sexual practices of the Jakarta Waria (male transvestites) in 1995

As the second part of a community based educational campaign to convey the risk of HIV/AIDS to commercial sex workers in Jakarta, from May-July 1995, a total of 253 male transvestites (WARIA) were questioned about their sexual behavior patterns and their knowledge and attitude toward HIV/AIDS. In the previous report, 1991-1993, there was one out of 830 WARIA found HIV positive in November 1993. In this study, 1995, a total of two out of 253 WARIA were confirmed of HIV infection in July 1995. Most of them still have incorrect knowledge on HIV/AIDS transmission mode, they are still practicing high risk sexual attitudes such as an exchange partner rate of 5 men per three weeks, low condom use (1.2 out of the last 5 sexual contacts). The reasons for not using condoms were forgetfulness 35.3% and partner does not like condom 38.2% Most of WARIA know about condoms (94.5%), but it is difficult to access condom use from small shops around them. Therefore, to prevent further spread of HIV/AIDS in WARIA, condom should be used constantly and properly. It has been shown from another study, that more information, better availability and better promotion of condoms can increase condom use. Thus, attention should be placed on various ways of distributing condoms for WARIA in Jakarta, especially community-based distribution by peer leaders, social marketing and commercial sales.

Pityriasis rubra pilaris: an unusual cutaneous complication of AIDS

Pityriasis rubra pilaris is an uncommon hyperkeratotic, papulosquamous disorder that has been reported in patients infected by HIV. We recount a case of pityriasis rubra pilaris in an HIV-seropositive man. A 36-year-old man with a history of ulcerative colitis and recurrent otitis externa had diffuse psoriaform erythroderma. He was treated initially with methotrexate and isoretinoin without clinical improvement. Skin examination showed large, erythematous, orange, scaly patches on the upper extremities and thickening of the nail beds. The palms and soles were hyperkeratotic. Skin biopsy revealed changes that were consistent with pityriasis rubra pilaris. Six months before the onset of symptoms, results of an enzyme-linked immunosorbent assay (ELISA) and Western Blot assay for HIV were negative. Six months after symptoms, results of repeat enzyme-linked immunosorbent assay and Western blots for HIV were positive (CD4+ T-cell count = 200 cells/ mm3). Clinical course had been complicated by episodes of Staphylococcus aureus bacteremia, mucocutaneous candidiasis, and development of localized squamous cell carcinoma of the skin. The increased severity of pityriasis rubra pilaris should prompt clinicians to consider coinfection with HIV in patients who have disease that is refractory to treatment. Clinicians also should remain vigilant for the development of squamous cell carcinoma.

Estrogen receptor mRNA in mineralized tissues of rainbow trout: calcium mobilization by estrogen

RT-PCR was undertaken on total RNA extracts from bone and scales of the rainbow trout, Oncorhynchus mykiss. The rainbow trout estrogen receptor (ER)-specific primers used amplified a single product of expected size from each tissue which, using Southern blotting, strongly hybridized with a 32P-labelled rtER probe under stringent conditions. These data provide the first in vivo evidence of ER mRNA in bone and scale tissues of rainbow trout and suggest that the effects of estrogen observed in this study (increased bone mineral and decreased scale mineral contents, respectively) may be mediated directly through ER.

Epidemic and sporadic hepatitis E virus transmission in West Kalimantan (Borneo), Indonesia

A cross-sectional survey was conducted in West Kalimantan (Borneo), Indonesia to geographically profile hepatitis E virus (HEV) prevalence in the riverine areas recognized as the foci of epidemic HEV transmission in 1987. Additionally, a contiguous, although distinct, population with no identifiable historical exposure to epidemic HEV was surveyed downstream for comparative purposes. Eight hundred eighty-five sera were assayed by enzyme immunoabsorbent assay for anti-HEV IgG and anti-hepatitis A virus (HAV) IgG markers. A very high percent (90%) of both the outbreak and comparison populations was anti-HAV IgG positive by the age of nine years. In contrast, the prevalence of anti-HEV IgG in the outbreak area (50%) was significantly higher than in the comparison area (23%) (P < 0.0001). In both the outbreak and comparison areas, anti-HEV IgG prevalence increased with age ( < 0.0001), except for the group > or = 50 years of age. The prevalence (53%) of antibody to HEV in the population > or = seven years of age from the outbreak area (alive during the actual 1987 outbreak) was significantly (P < 0.0001) greater than among the children < seven years of age (born after the outbreak) (15%). However, anti-HEV IgG prevalence among the population from the comparison area did not differ significantly between the > or = seven- (23%) and < seven- (20%) year-old age groups. The percentage of anti-HEV IgG-positive individuals among males (47%) from the outbreak area was lower (P < 0.05) compared with females (55%). While overall usage of river water for drinking purposes was not universal, dependence on river water as a primary source was significantly higher (P < 0.001) in households from the outbreak area (60%) compared with the comparison area (30%). This study indicates persistence of an anti-HEV IgG response in a large percentage of the population seven years after an epidemic of HEV infections. Also, the relatively high prevalence (15%) of anti-HEV in children < seven years of age from the outbreak area reflects continuing, sporadic infections.

Indium-111-leukocyte imaging: a case of peritonitis mimicking inflammatory bowel disease

Leukocytes labeled with 99mTc-HMPAO and 111In have been used extensively in imaging inflammatory disorders, including inflammatory bowel disease (IBD), which has the appearance of tubular bowel activity. Peritonitis is inflammation of the serosal surfaces lining the peritoneal cavity which envelopes the bowel, giving a pattern of diffuse abdominal uptake on imaging. We present a case of an elderly man with surgically and pathologically confirmed peritonitis whose preoperative leukocyte scan mimicked the findings of IBD. Our findings suggest that diffuse peritonitis can mimic IBD on an 111In-leukocyte scan.

The value of breast lumpectomy margin assessment as a predictor of residual tumor burden

PURPOSE

Margin assessment is commonly used as a guide to the relative aggressiveness of therapy for breast conserving treatment (BCT), though its value as a predictor of the presence, type, or extent of residual tumor has not been conclusively studied. Controversy continues to exist as to what constitutes a margin that is "positive," "close," or "negative." We attempt to address these issues through an analysis of re-excision specimens.

PATIENTS AND METHODS

As part of an institutional prospective practice approach for BCT, 265 cases with AJCC Stage I/II carcinoma with an initial excision margin that was < or = 2 mm or indeterminate were subjected to re-excision. The probability of residual tumor (+RE) was evaluated with respect to tumor size, histopathologic subtype, relative closeness of the measured margin, the extent of margin positivity graded as focal, minimal, moderate, or extensive, and the extent of specimen processing as reflected in the number of cut sections per specimen volume (S:V ratio). The amount of residual tumor was graded as microscopic, small, medium, or large. The histopathologic subtype of tumor in the re-excision specimen was classified as having an invasive component (ICa) or pure DCIS (DCIS).

RESULTS

The primary excision margin was positive, > 0 < or = 1 mm, 1.1-2 mm, and indeterminate in 60%, 18%, 5%, and 17%, respectively. The predominant histopathologies in the initial excision specimens were invasive ductal (IDC) (50%) and tumors with an extensive intraductal component (EIC) (43%). The histopathology of the initial excision specimen was highly predictive of the histopathology of tumor found on re-excision, as residual DCIS was found in 60% of +RE specimens with initial histopathology of EIC compared to 26% for IDC (p = 0.001). Neither the extent of margin positivity nor the extent of tumor in the re-excision were significantly related to the initial histopathologic subtype; however, a +RE was seen in 59% of EIC, 43% of IDC, and 32% of invasive lobular ILC cases (p = 0.01). The extent of margin positivity was significantly related to the size of the tumor such that tumor size < or = 20 mm was associated with a greater probability of focal or minimal margin involvement. Positive margins graded as focal, minimal, moderate/extensive were associated with a +RE in 26%, 58%, and 84%, respectively (p = 0.001). Further, the extent of positivity was significantly correlated with the extent of residual tumor such that focal/minimal positivity was more commonly associated with micro/small +RE, whereas moderate/extensive positivity was associated with medium/large +RE. When the closest margin of the initial excision specimen was positive, > 0 < or = 1 mm, or 1.1-2 mm, a +RE was found in 56%, 41%, and 17%, respectively (p = 0.01) but did not correlate with the amount of residual tumor. The extent of specimen processing as reflected in the S:V ratio did not correlate with the probability of defining a measured margin as positive nor the probability of a +RE. In a univariate model, the extent of tumor in the re-excision and the histologic type of tumor in the re-excision were significantly associated with margin status and initial histopathology, respectively. The probability of finding a +RE, based on a multivariate model, was associated with the closeness and extent of margin involvement and initial histopathology of an EIC.

CONCLUSION

The relative closeness of tumor to the specimen edge and the extent of margin positivity are predictive for residual tumor, though with an error consistent with its limitations as a sampling procedure. The histopathology of tumor in the initial excision is predictive of the type of residual tumor and the extent of margin positivity was correlated with the amount of residual tumor.

Expression of members of a novel membrane linked metalloproteinase family (ADAM) in human articular chondrocytes

Using resting chondrocytes derived from human articular femoral head and a conditionally immortalised human articular chondrocyte cell line we have studied the expression of members of the novel metalloproteinase/disintegrin family termed ADAM. Using RT-PCR we can detect the expression of ADAM-12 a novel family member isolated from myeloma cells [1]. We also find expression of ADAM 10 a functional metalloproteinase/disintegrin first isolated from bovine brain and ADAM-15 a metallodisintegrin isolated from mammary derived epithelial cells. Northern blotting was used to confirm expression. One main transcript is visible for ADAM-12 whereas both ADAM-10 and ADAM-15 have multiple transcripts indicating possible RNA variants potentially derived from alternative splicing or alternative use of polyadenylation sites. Since chondrocytes are proposed as an important source of metalloproteinase enzymes involved in joint pathology the potential relevance of the expression of these molecules to connective tissue disorders is discussed.

Acute viral hepatitis in Hanoi, Viet Nam

A study of acute hepatitis was conducted in Hanoi, Viet Nam, from January 1993 to February 1995; 188 sera from clinical hepatitis cases were screened by enzyme-linked immunosorbent assay for immunoglobulin (Ig) M anti-hepatitis A virus (HAV), IgM anti-hepatitis B core antigen (HBc), IgG anti-hepatitis C virus (HCV), IgG anti-hepatitis E virus (HEV) and IgM anti-HEV. Additionally, 187 sera from control subjects, matched by age, sex and month of admission, with no recent history of hepatitis, were tested for comparative purposes. There was serological evidence of recent HAV (29%) and hepatitis B virus (24%) infection in 53% of cases (2 mixed infections), compared with 2% of controls. HCV infections were detected in 10% of cases (with no IgM anti-HAV or IgM anti-HBc) and in 1% of control sera. There was no significant difference in the proportion of IgG anti-HEV positive sera between cases (in the absence of IgM anti-HAV or IgM anti-HBc) (21%) and controls (14%); 3% of all case sera were IgM anti-HEV positive. Younger cases (< 20 years) were more likely to have recent HAV infections (41%) than those aged > or = 20 years (21%) (P < 0.01). In contrast, a higher percentage of adult cases had IgM anti-HBc, IgG anti-HCV and IgG anti-HEV (in the absence of recent HAV or HBV infection) than did children. No seasonal trend in hepatitis admissions was detected, nor an association between water-borne infections (HAV and HEV) and the warmer months. Hepatitis patients lived throughout Hanoi and surrounding areas, with no identifiable geographical clustering, regardless of serological marker.

A randomised phase II study of sialyl-Tn and DETOX-B adjuvant with or without cyclophosphamide pretreatment for the active specific immunotherapy of breast cancer

Studies in animal models of mouse mammary carcinoma have shown that ovine submaxillary mucin, which carries multiple sialyl-Tn (STn) epitopes, is effective in stimulating an immune response and inhibiting tumour growth. In similar studies using carbohydrate antigens, pretreatment with low-dose cyclophosphamide has been shown to be important in modulating the immune response to antigen possibly by inhibiting suppresser T-cell activity. In a clinical trial assessing the efficacy and toxicity of synthetic STn, patients with metastatic breast cancer were randomised to receive 100 micrograms STn linked to keyhole limpet haemocyanin (KLH) with DETOX-B adjuvant given by subcutaneous injection at weeks 0, 2, 5 and 9 with or without low-dose cyclophosphamide (CTX, 300 mg m-2) pretreatment, 3 days before the start of immunotherapy. Patients with responding or stable disease after the first four injections were eligible to receive STn-KLH at 4 week intervals. The main toxicity noted was the development of subcutaneous granulomata at injection sites. Of 23 patients randomised, 18 received four injections, 5 patients having developed progressive disease during the initial 12 week period. Two minor responses were noted in the 18 patients who received four active specific immunotherapy (ASI) injections and a further five patients had stable disease. Six patients continued ASI at 4 week intervals and a partial response was noted in a patient who had previously had stable disease. All patients developed IgG and IgM responses to sialyl-Tn and levels of IgM antibodies were significantly higher in those patients who were pretreated with CTX. Measurable tumour responses have been recorded following ASI with STn-KLH plus DETOX and the immunomodulatory properties of low-dose CTX have been confirmed.

An assessment of pain and return to normal activity. Laparoscopic herniorrhaphy vs open tension-free Lichtenstein repair

BACKGROUND

Laparoscopic herniorrhaphy is controversial and deserves critical evaluation.

METHODS

In a randomized prospective study transabdominal preperitoneal laparoscopic herniorrhaphy (n = 24) was compared in patients to the tension-free Lichtenstein repair (n = 29) utilizing validated and reliable pain and activity assessment tools. The Sickness Impact Profile (SIP) was used to compare preoperative normal activity to postoperative activity. A Pain-O-Meter (visual analogue scale plus affective and sensory pain descriptors) assessed intensity of pain. The total pain assessment score and SIP were compared across time (postoperative day 1-42). Analgesic medication was used as a covariate.

RESULTS

The total pain score was less for laparoscopic herniorrhaphy but this did not reach statistical significance. Similarly, the SIP showed modest improvement for laparoscopic herniorrhaphy. No differences between groups were noted for morphine equivalents of administered analgesics or length of hospitalization.

CONCLUSION

Further investigation of laparoscopic herniorrhaphy is warranted.

Results of the 1996 National Resident Matching Program: family practice

The results of the 1996 National Resident Matching Program (NRMP) set records in the number of positions filled in family practice residencies, with a 10.8% increase over 1995 (2,840 vs 2,563) and a 9.4% increase in positions filled with US seniors (2,276 vs 2,081). This is the largest number of US seniors choosing family practice in the history of the NRMP. A total of 196 (6.7%) more positions were offered in family practice through the NRMP, compared with 1995 (3,137 vs 2,941). Thus, 195 of these additional 196 positions were filled with US seniors. In keeping with the trend begun in 1992, 242 more positions were filled on July 1, 1996, than 1995 (3,494 vs 3,252), for a fill rate of 97.8%. Internal medicine residencies matched 67 fewer US seniors in 1996, while pediatric residencies matched 85 more US seniors. During the past 4 years, family practice has been the choice of 82.6% of the additional US seniors choosing a primary care residency. With continued record increased interest in family practice as a career choice and the need for more family physicians, priority support for the nation's family practice residency programs continues to be of critical importance.

Entry of US medical school graduates into family practice residencies: 1995-1996 and 3-year summary

This is the 15th report prepared by the American Academy of Family Physicians (AAFP) on the percentage of each US medical school's graduates entering family practice residency programs. Approximately 14.6% of the 16,124 graduates of US medical schools between July 1994 and June 1995 were first-year family practice residents in October 1995, compared with 13.4% in 1994 and 12.3% in 1993. This is the highest percentage since 1980-1981 (12.8%), when this series of studies began. Medical school graduates from publicly funded medical schools were almost twice as likely to be first-year family practice residents in October 1995 than were residents from privately funded schools, 18% compared with 9.7%. The West North Central region reported the highest percentage of medical school graduates who were first-year residents in family practice programs in October 1995 at 24.8%; the Middle Atlantic and New England regions continued with the lowest percentages at 7.6% and 9.3%, respectively. Approximately one in two medical school graduates (46.7%) entering a family practice residency program as first-year residents in October 1995 entered a program in the same state where they graduated from medical school. The percentages for each medical school have varied substantially from year to year since the AAFP began reporting this information. The average percentage for each medical school for the last 3 years is reported. In addition, the number and percentage of graduates from colleges of osteopathic medicine who entered Accreditation Council for Graduate Medical Education-accredited family practice residency programs are reported.

A waterborne outbreak of hepatitis E virus transmission in southwestern Vietnam

A hepatitis outbreak affecting primarily adults occurred in southwestern Vietnam, along the Hau river bordering Cambodia, in June and July 1994. One month after the outbreak, sera and epidemiologic information were collected from 150 subjects: 50 patient cases, 50 matched, healthy community controls, and 50 geographic controls living 50 km upriver. The prevalence of immunoglobulin G (IgG) to hepatitis E virus (HEV) was significantly (P < 0.001) higher (76%) among cases than among the matched (38%) and geographic (38%) control populations. Immunoglobulin M to HEV was detected by enzyme-linked immunosorbent assay and Western blot in 16% of sera collected from patients one month after the outbreak. Hepatitis E virus RNA was detected with the polymerase chain reaction in 6% of sera from patients; RNA was not detected in either control group. These results indicate that HEV was the etiologic agent responsible for the outbreak. Children were under-represented among clinical cases. River water served as the principal source for drinking and bathing among most (96%) of the case and control study populations. Boiling of drinking water was negatively associated (P < 0.05) with IgG anti-HEV seropositivity. Unusually heavy rainfall likely contributed to conditions that favored the outbreak. This is the first recognized outbreak of epidemic HEV transmission in Indo-China.