The sweet side of life: nectar sugar type and concentration preference in Wahlberg's epauletted fruit bat.

Whether nectarivores or frugivores place selective pressure on the plants they feed on, in terms of nectar or fruit traits, is much debated. Globally sugar preferences, concentration preference and digestive ability of avian nectarivores have been extensively researched. In contrast, relatively little is known about mammalian nectarivores or frugivores in terms of these, particularly Old World species. Consequently effect of sugar type and concentration on food preference in Wahlberg's epauletted fruit bat Epomophorus wahlbergi was investigated. Pair-wise choice tests were conducted using equicaloric hexose and sucrose solutions at five different concentrations (5%-25%). It was expected that they would prefer hexose sugars as these are dominant in available indigenous fruits. However, bats preferred hexoses only when offered dilute (5%) concentrations. From 10% to 25% they showed a decrease in volume intake. Their body mass was generally higher and similar after feeding during the night with the exception of 5% concentration where the mean body mass decreased. When E. wahlbergi were offered a range of sucrose or hexose solutions (10%-25%) respectively, they showed no concentration preference in terms of total volume consumed, nor energy intake. These findings suggest that these fruit bats do not appear to act as a selective pressure on sugar composition in Old World fruit. In fruit bats with high energy requirements, dietary flexibility may be an advantage when faced with seasonal and unpredictable fruit availability.

Variation in urine concentrating ability and water balance of the black-tailed tree rat Thallomys nigricauda, along an aridity gradient.

Mechanisms behind variation in physiological traits may assist in explaining how certain traits have evolved. The ability of mammals to concentrate urine has been seen as an adaptation to xeric environments. Urine osmolality and relative medullary thickness (RMT) are two indices which indicate urine concentrating powers. In addition, mammals living in xeric regions have lower water turnover rates (WTR) than their mesic counterparts. The RMT, urine concentrating ability (UCA) and WTR of the Black-tailed Tree Rat, Thallomys nigricauda, were investigated at three study sites along an aridity gradient. We investigated the extent to which these traits are influenced by evolutionary adaptation and/or phenotypic flexibility. There was no significant difference in RMT between sites and no difference in osmolalities when site and season were taken into account. In addition, there was no significant effect of site and season on WTR. This suggests that these traits might have a genetic basis, and reflect an evolutionary adaptation. Lack of differences in the renal traits in T. nigricauda across their range may be interpreted as lack of phenotypic flexibility. However, as a consequence of the degree of individual variation in the parameters measured there appears to be phenotypic flexibility with individuals responding to their specific conditions. This has positive implications for the survival of the species in the light of climate change.

Diagnostic dilemma: extremely low birth weight baby with staphylococcal scalded-skin syndrome or toxic epidermal necrolysis.

Exfoliative skin diseases of the neonate are relatively rare but when present require rapid diagnosis and treatment to decrease morbidity and mortality associated with these entities. We present the case of a 795 g premature male infant who developed exfoliative lesions on day of life 66. Skin and blood cultures were obtained and intravenous antibiotics initiated. Results of a Tzanck smear suggested toxic epidermal necrolysis (TEN), so the infant was emergently transferred to a local children's hospital with burn unit capabilities for further care. Further histopathological evaluation of the skin biopsy confirmed the diagnosis of staphylococcal scalded-skin syndrome (SSSS). The desquamation ceased 24 h after the initiation of antibiotic therapy, and the skin lesions resolved within 10 days. We discuss the pathogenesis of SSSS and TEN and highlight the importance of early diagnosis so appropriate treatment can be initiated.

Relationship between staffing ratios and effectiveness of inpatient psychiatric units.

OBJECTIVE: Most staffing models designed for adult psychiatric hospitals are based on the well-known relationship between high staff-patient ratios and high effectiveness of treatment units. Staffing ratios likely gain their predictive power by serving as a proxy measure for the amount of attention patients receive from staff. This study directly measured the amount of attention that patients received from staff to determine whether it could account for the variance in unit effectiveness predicted by staffing ratios and serve as a better predictor of unit effectiveness. METHODS: Data from 22 wards in state or Department of Veterans Affairs mental health institutions, which housed 673 short- and long-stay patients, were analyzed. Only full-time direct care staff were included in the calculation of staff-patient ratios. The amount of attention provided to patients by staff was determined over seven days by a highly reliable observational assessment system. The two best social-action outcome measures over a six-month period were adjusted for confounding variables to provide residualized indexes of unit effectiveness. RESULTS: Staff-patient ratios significantly predicted unit effectiveness as indexed by residualized community tenure, accounting for 24 percent of the variance. However, staff-patient ratios did not significantly predict unit effectiveness as indexed by net gain in discharge rates. Taking into account the amount of staff attention received by patients significantly improved the prediction of community tenure by 36 percent and the net gain in discharge rates by 66 percent over staffing ratios alone. The amount of staff attention also accounted for the relationship between staffing ratios and community tenure. CONCLUSIONS: Staffing decisions should be made on the basis of more precise information about treatment requirements, not just staffing ratios.

Rapid platelet-function assay: an automated and quantitative cartridge-based method.

BACKGROUND: The platelet glycoprotein (GP) IIb/IIIa receptor is important in mediating platelet thrombus formation, and the GP IIb/IIIa antagonist abciximab (c7E3 Fab; ReoPro) is effective in preventing thrombotic ischemic cardiovascular complications of unstable angina and percutaneous coronary interventions. Small-molecule antagonists of GP IIb/IIIa based on the Arg-Gly-Asp (RGD) sequence show similar benefit, and some of these agents are orally active. However, there may be significant interindividual variation in response to such antagonists, especially with chronic oral therapy. It will be essential to balance the beneficial antithrombotic effect of these drugs with their potential for causing bleeding. In response to this need, we have developed a rapid platelet-function assay (RPFA), a point-of-care system that provides a quantitative measure of the competence of the GP IIb/IIIa receptor as reflected in the ability of platelets to agglutinate fibrinogen-coated beads. METHODS AND RESULTS: Polystyrene beads were coated with fibrinogen and placed in a cartridge along with a lyophilized peptide that activates the thrombin receptor. Anticoagulated whole blood was added to the cartridge, and then a microprocessor-controlled operation mixed the reagents and detected agglutination between platelets and coated beads. Quantitative digital results were displayed within 3 minutes. Because there is no dilution of the blood, the assay can be used to measure platelet activity in samples that have been treated with GP IIb/IIIa antagonists with high dissociation rates. RPFA results of whole-blood samples treated with different GP IIb/IIIa antagonists correlated well with both conventional turbidimetric platelet aggregation (r2=0.95) and the percentage of free GP IIb/IIIa molecules in the sample (r2=0.96). The mean difference in measurements between RPFA and aggregometry was -4% (+/-4% SD), and the mean difference in measurements between RPFA and free GP IIb/IIIa receptors was -2% (+/-6% SD). CONCLUSIONS: The RPFA provides rapid information on platelet function that mirrors turbidimetric platelet aggregation and reflects GP IIb/IIIa receptor blockade.

Acute sporadic hepatitis in the Republic of Yemen.

The causes of acute icteric viral hepatitis were determined in 78 adult Yemeni patients. Acute hepatitis B (IgM anti-HBc positive) was the most common type (26.9%). Acute hepatitis E (IgM anti-HEV positive) occurred in 14% and was not associated with travel outside Yemen. Sixty percent of all 78 patients were positive for IgG anti-HEV as were 40% of a series of 48 healthy male blood donors and pregnant females, indicating that HEV is prevalent in Yemen. Acute hepatitis A (IgM anti-HAV positive) and hepatitis C and D were responsible for 5.1%, 6.4%, and 2.6% cases, respectively. This totals to 106%, as an infection with two viruses occurred in 6.4% cases. In 51.3% of all cases, no virological markers of acute hepatitis were detected, suggesting an as yet undiscovered agent.

Hepatitis A seroprevalence in homosexual and heterosexual men.

OBJECTIVE: To determine the seroprevalence of hepatitis A antibodies in homosexual and heterosexual males attending a genitourinary medicine (GUM) clinic. DESIGN: Prospective study of male patients recruited from a GUM clinic during a 10 week period in 1993. SETTING: Central London outpatient GUM department at Chelsea and Westminster Hospital. SUBJECTS: 255 patients were recruited, comprising 185 homosexual and 70 heterosexual males. Ninety two men were known to be HIV-positive, of whom 89 were homosexual. MAIN OUTCOME MEASURES: Serum samples were screened for both IgM and IgG antibodies to hepatitis A by enzyme linked immunoassay. Results were matched to an anonymously completed questionnaire. RESULTS: 81 of the 255 subjects (31.8%) had been exposed to hepatitis A, two of whom were IgM positive. There were similar hepatitis A seroprevalence rates in homosexual (32.4%) and heterosexual men (30.0%). Although 48.1% of the homosexual men were known to be HIV-positive, compared with 4.3% of the heterosexuals. Hepatitis A seroprevalence remained comparable in both groups after patients with known HIV infection were excluded from the analysis. 11.4% of the heterosexual men admitted to oral-anal sexual contact compared with 62.2% of the homosexual men. This sexual practice was not associated with antibodies or a past history of hepatitis A exposure. CONCLUSIONS: There was no detectable difference in hepatitis A seroprevalence between male homosexual and heterosexual GUM clinic attenders, despite a much higher level of oral-anal sexual activity among the homosexual population.

Severe rotavirus-associated diarrhoea following bone marrow transplantation: treatment with oral immunoglobulin.

Two patients developed acute severe rotavirus-associated diarrhoea following BMT. Both received treatment with oral immunoglobulin and in each case the diarrhoea substantially resolved within 3 days, and rotavirus became undetectable in their stool. Oral immunoglobulin may be a useful therapy for rotavirus gastroenteritis post-BMT.

Assessment of cognitive appraisal and coping linkages using two forms of canonical correlation.

As a conceptual framework for research on stress and coping, the transactional model of Lazarus and Folkman is process-oriented and requires methodologies that capture the process nature of cognitive appraisal and coping across stages of a transaction. Two forms of canonical correlation were used to analyze strength of association measures between pairs of cognitive appraisal and coping variable sets for 138 student subjects. Analysis indicated that, when an environmental transaction includes more than one time period, the generalized canonical correlation approach may offer some advantages in assessing linkage strength over the pairwise method.

Hepatitis E--an important cause of imported non-A, non-B hepatitis among migrant workers in Qatar.

In 1985, Glynn et al. [Journal of Medical Virology 17:371-375] reported on epidemic viral hepatitis in Qatar and concluded that 72% (91/126) had acute enterically transmitted non-A, non-B viral hepatitis (ET-NANBH). Most of the patients (98%) presented within 8 weeks of arrival in Qatar and were migrant workers from the Indian subcontinent. The data was reanalysed for evidence of infection with hepatitis E virus (HEV). Seventy-eight of 91 (86%) of stored sera were still suitable for analysis since collection in 1981. A newly described enzyme immunoassay (EIA) for both IgG and IgM anti-HEV was used (Abbott Laboratories, Delkenheim, Germany); 59/78 (76%) were positive for either or both assays. All but two were from the Indian subcontinent. The data suggest that HEV was the major cause of ET-NANBH in Qatar in 1981, particularly among newly arrived migrant workers from the Indian subcontinent.

Prevalence of hepatitis B, C, and D virus markers in Yemeni patients with chronic liver disease.

A serological survey for hepatitis B, C, and D markers was carried out in the Yemen Republic. Serum samples from 243 pregnant females, 294 male blood donors, and 108 patients with chronic liver disease were examined. Hepatitis B surface antigen (HBsAg) was found in 18.5% healthy individuals and 24.1% patients with chronic liver disease (P = 0.03). Evidence of any marker for hepatitis B virus (HBV) infection was found in 59.8% healthy individuals and 75.9% of patients with chronic liver disease (P = 0.0016). HBeAg was detected in 32.1% of the HBsAg-positive pregnant females, indicating that vertical transmission probably plays a part in forming the pool of HBV carriers. Vaccination against HBV as part of the extended programme of immunisation (EPI) is recommended. Antibodies to hepatitis D were found in only 2 of 100 HBsAg-positive sera. Antibodies to hepatitis C (anti-HCV) were found in 2.1% healthy individuals and 21.5% patients with chronic liver disease (P = 0.0001). These results indicate that hepatitis B is hyperendemic in the Yemen Republic but that hepatitis D is very uncommon. The prevalence of anti-HCV is higher than in Europe and similar to neighbouring Arab countries. Infection with both HBV and HCV are important causes of chronic liver disease in the Yemen Republic.

Adolescents' perceptions of significant individuals in their lives.

180 adolescents, aged 11-12 years, and 180, aged 15-16 years, from one Scottish secondary school participated in this study. The purposes of the investigation were: to determine the most significant family member and unrelated person in young peoples' lives; and to identify which characteristics rendered these persons important. 'Mother' and '(same sex) friend' emerged as the outstanding choices. Family members (except siblings) were associated with positive characteristics, whilst amongst unrelated adults, youth group leaders were viewed positively. By contrast, school teachers were primarily seen as occupying a challenging role. Where age and sex differences were found, it was invariably those in early adolescence and females who were more likely to attribute positive characteristics. These results are discussed in relation to the concept of 'mentoring' and the role of mentors in adolescents' lives.

Prevalence of antibodies to hepatitis C in dialysis patients and transplant recipients with possible routes of transmission.

The prevalence of hepatitis C infection and possible predisposing factors was assessed in a renal unit. Of 343 patients at our renal dialysis centre, 37 (10.8%) were anti-HCV positive by a 1st-generation assay (ELISA, Ortho/Chiron) and confirmed positive in 35 (10.2%) with a 2nd-generation test (UBI, New York). Anti-HCV positivity was significantly associated with: duration of renal replacement therapy (P < 0.0001); quantity of blood transfused (P < 0.002); duration of hospital haemodialysis (P = 0.0001); duration with a functional renal transplant (P = 0.039); and aspartate aminotransferase (P < 0.0001). Logistic regression determined the following variables to be independent risk factors: duration of renal replacement therapy with a relative risk of 34.3 for 5-9 years and 87.4 when the duration was in excess of 10 years; renal transplant for less than 1 year (relative risk of 5.0); transfusion in excess of 50 units of blood (relative risk of 11.6). Clinical assessment of anti-HCV-positive patients revealed peripheral signs of chronic liver disease in 40%, hepatomegaly in 34%, and splenomegaly in 9%. This prevalence of hepatitis C infection is similar to other European and North American centres, but contrasts with low prevalence rates reported from dialysis populations in the UK. It adds further support for routine screening of blood and possibly organ donors and implementation of further infection control measures in dialysis centres.

Diminished response to recombinant hepatitis B vaccine in homosexual men with HIV antibody: an indicator of poor prognosis.

Three doses of a recombinant DNA HBV vaccine (MSD) were given to healthy male homosexuals. Seventy-eight out of 104 (77.6%) participants had detectable antibody (anti-HBs) two months after the third dose. Seroconversion occurred in only 9 out of 27 subjects (33.3%) who were anti-HIV positive compared with 69 out of 77 (89.6%) who were negative (chi 2 = 30.8; P less than .001). Fifteen of the 18 anti-HIV positive who did not mount an antibody response to the hepatitis B vaccine (anti-HBs) later progressed to persistent generalised lymphadenopathy syndrome (5), AIDS-related complex (5), and AIDS (5). Only one of the nine anti-HIV positive anti-HBs responders developed PGL (chi 2 = 10.14; P less than .005). Our results show that anti-HIV positive homosexuals are poor responders to the recombinant hepatitis B vaccine and anti-HIV positive non-responders are more likely to develop clinically apparent HIV infection.

Long-term results with the above-knee popliteal expanded polytetrafluoroethylene graft.

Since approximately 30% to 40% of autogenous vein bypass grafts to the femoropopliteal level may occlude within 5 years of implantation, additional vein will be required for subsequent revisions. We undertook a study to determine whether the preferential use of an above-knee expanded polytetrafluoroethylene bypass graft to save vein is an appropriate option. We reviewed our experience with 114 above-knee expanded polytetrafluoroethylene bypass reconstructions. Life-table analysis of primary and secondary graft patency was carried out by the method of Peto and statistically analyzed for the influence of clinical indication, runoff as determined by both preoperative and intraoperative completion arteriography, smoking, and diabetes. The 5-year primary patency rate of 57% for patients with claudication was comparable to contemporary randomized or retrospective series with below-knee autogenous vein for that indication, and it was superior to the patency rate for limb salvage. The status of the runoff vessels was an important determinant of outcome. The 59 limbs with good arteriographic runoff (2 to 3 vessels) had a markedly higher 5-year patency rate (70%) than the poor arteriographic runoff (0 to 1 vessels) group (30%). Continued cigarette smoking and diabetes mellitus also appeared to affect adversely primary graft patency in our hands. Our data support the use of preferential above-knee expanded polytetrafluoroethylene grafts in patients with good angiographic runoff. This approach does not appear to prejudice the limb against secondary revisionary procedures or the use of a new autogenous graft, if required.

Pre-S proteins in hepatitis B.

Two reactive sequences of the pre-S regions of hepatitis B surface antigen were synthesized chemically and used in micro-ELISAs for the assay of pre-S1 and pre-S2 antigens in serum from patients with acute and chronic hepatitis B. Pre-S1 antigen correlated well with the presence of HBV-DNA and was no longer detectable on cessation of viral replication, after natural recovery and after successful treatment with alpha-interferon. Pre-S2 proteins were also lost after treatment with alpha-interferon. The results show that the assay of pre-S1 and pre-S2 proteins in serum provides additional useful markers for assessing patients with acute and chronic hepatitis B infection and for monitoring the response to treatment with interferon.

Early diagnosis of cytomegalovirus infection in renal transplant and dialysis patients by DNA-DNA hybridisation assay.

One hundred forty-eight urine specimens were collected from 47 renal transplant and dialysis patients and screened for the detection of cytomegalovirus (CMV). Diagnosis of CMV infection was suggested in 17 out of 47 patients (36.2%) by more than one of the five methods used. DNA hybridisation assay (DNA HA) using 32P-labelled probe detected CMV DNA in 15 (31.9%) of 47 patients, whereas virus isolation on conventional tube cell cultures (CTC), immunofluorescence incorporating monoclonal antibodies on centrifugation vial cultures (IF), complement fixation test (CFT), and electron microscopy (EM) yielded positive results in only nine (19.2%), 12 (25.2%), 11 (23.4%), and one (2.1%) of 47 patients, respectively. The significance of these results obtained by DNA HA lies not only in the apparent increase in number of patients diagnosed, but also in both early and rapid detection of CMV DNA. More importantly, the DNA HA is highly specific in that it correlates accurately with clinical and laboratory data characteristic of CMV disease. In respect of clinically manifest CMV disease, the specificity of DNA HA, CTC, IF, CFT, and EM was 87.5, 43.7, 56.3, 43.7, and 6.3%, respectively. These advantages of DNA HA make it the test of choice for early diagnosis of CMV infections in immunosuppressed patients.

Detection of human cytomegalovirus by slot-blot hybridisation assay employing oligo-primed 32P-labelled probe.

A 32P-labelled Hind III-0 DNA fragment (nine Kilobases; Kb) from human cytomegalovirus AD-169 (HCMV) was used in slot-blot hybridisation assay for the detection of HCMV in clinical samples. The results obtained with DNA hybridisation assay (DNA HA) were compared with virus isolation using conventional tube cell culture (CTC) and centrifugation vial culture (CVC), immunofluorescence (IF), and complement fixation test (CFT). Of 15 CTC-positive samples, 13 were positive with DNA HA (sensitivity 86.7%). Also, 14 additional samples were DNA HA-positive but CTC-negative. CVC and/or IF confirmed the diagnosis in nine of 14; the remaining five samples were from three patients who showed fourfold rising antibody titre by CFT. Although DNA HA using 32P-labelled probes is relatively cumbersome and expensive, it is a valuable test for quantitation of viral shedding in patients with HCMV infections who may benefit from antiviral therapy.

Combined use of sonication and monoclonal antibodies for the detection of early and late cytomegalovirus antigens in centrifugation cultures.

A total of 157 clinical specimens was inoculated into shell vials and conventional tube cell cultures containing confluent monolayers of human embryonic lung fibroblasts (HELF). Of 31 clinical cytomegalovirus (CMV) isolates, 30 specimens (96.8%) were positive by the immunofluorescence method on centrifugation vial cultures (CVC-IF), whereas the cytopathic effects (CPE) of CMV were detected in only 14 specimens (45.2%) in conventional tube cell cultures (CCC), P less than 0.001 and in 22 specimens (70.9%) in centrifugation vial cultures (CVC-P), P less than 0.1. Significantly more fluorescent foci were detected in centrifugation cultures inoculated with sonicated urine samples (P less than 0.001). CVC-P is more sensitive than CCC for the diagnosis of CMV (P less than 0.05), and a highly significant difference was observed when we compared the mean day to initial detection of CPE (P less than 0.001). For optimal detection of CMV, both CVC-IF and CVC-P should be used for the laboratory diagnosis of this virus infection.