Fatal avian influenza A (H5N1) in a child presenting with diarrhea followed by coma

In southern Vietnam, a four-year-old boy presented with severe diarrhea, followed by seizures, coma, and death. The cerebrospinal fluid contained 1 white cell per cubic millimeter, normal glucose levels, and increased levels of protein (0.81 g per liter). The diagnosis of avian influenza A (H5N1) was established by isolation of the virus from cerebrospinal fluid, fecal, throat, and serum specimens. The patient's nine-year-old sister had died from a similar syndrome two weeks earlier. In both siblings, the clinical diagnosis was acute encephalitis. Neither patient had respiratory symptoms at presentation. These cases suggest that the spectrum of influenza H5N1 is wider than previously thought.     

Exercise as a treatment for hypertension in low-socioeconomic-status black children

Low-socioeconomic-status (SES) Black children have a higher mean blood pressure than most other groups. The antihypertensive effects of a 12-week aerobic exercise program were examined on 11 low-SES Black children, ages 8-12, who had blood pressure above the 95th percentile. A multiple baseline across three groups of children with baseline and exercise conditions was conducted. After the introduction of the exercise program, there were significant decreases in diastolic and systolic blood pressure. Cardiovascular fitness improved concurrently. The results suggest that vigorous exercise can decrease the blood pressure of low-SES hypertensive Black children.     

Development of an intracorporeal Thoratec ventricular assist device for univentricular or biventricular support

There is a need for a small, simple, and versatile intracorporeal ventricular assist device (IVAD) as an alternative to the large implantable electromechanical LVAD systems in current use. Because the basic design of the Thoratec paracorporeal VAD has been demonstrated in over 1,000 patients, weighing from 17 to 144 kg, and for durations up to 515 days including patient discharge (by using the portable driver), we are developing a new intracorporeal version of our VAD. This IVAD has a smooth contoured, polished titanium housing, and maintains the same blood flow path and Thoralon polyurethane blood pumping sac as the paracorporeal VAD. The IVAD is controlled with the Thoratec TLC-II Portable VAD Driver, which is a small briefcase sized, battery powered, pneumatic control unit. Intracorporeal LVADs and/or RVADs are implanted in a preperitoneal position, with a single small (9 mm OD) percutaneous pneumatic driveline for each VAD. The major advantages of the new IVAD design are size and simplicity. The IVAD weight (339 g) and implanted volume (252 ml) are substantially smaller than current implantable electromechanical LVAD systems. Only the small blood pump is implanted, leaving the more complex control unit external, where it can be serviced and replaced. The versatile design is intended for left and/or right heart support in large or small patients. The IVAD in combination with the TLC-II portable driver will be a viable and attractive alternative to large, implanted electromechanical systems.     

Aging does not alter cytosolic calcium levels of cortical synaptosomes in Fischer 344 rats

Several lines of experimental evidence support an association between altered Ca²⁺ regulation and aging. It has been supposed that free cytosolic Ca²⁺ concentrations ([Ca²⁺]_i) may decrease or increase in aged animals. In this study, both resting and KCl-stimulated [Ca²⁺]_i were measured in purified cortical synaptosomes from young (3 mo.), middle-aged (12 mo.), and old (24 mo.) Fischer 344 rats. Two additional groups of rats were included, one middle-aged and one old which were trained on a treadmill for 6 months prior to experimentation. The [Ca²⁺]_i was determined using the fluorescent Ca²⁺ chelator fura-2. Net KCl-dependent changes (ΔK) in [Ca²⁺]_i were determined by the difference between stimulatory (100 μM Ca²⁺/60 mM KCl) and resting (100 μM Ca²⁺/5 mM KCl buffer) conditions among the 3 age groups. Significant increases in [Ca²⁺]_i were observed in each age group upon depolarization with 60 mM KCl. However, there were no significant age-dependent differences in either resting [Ca²⁺]_i or KCl-stimulated [Ca²⁺]_i.     

Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis

Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.     

A technique for eliminating allele specific amplification failure during DNA amplification of heterozygous cells for preimplantation diagnosis

Advances in techniques of molecular biology have made possible the amplification of specific genes from single cells. This has a major clinical application in preimplantation diagnosis of monogenic disorders. However, the incidence of allele specific amplification failure (allele drop out) in heterozygous single cells can lead to misdiagnosis and the transfer of affected embryos. Few studies have been done to investigate the actual cause of allele drop out, although some investigators have succeeded in reducing but not eliminating it. Here we report the efficiency of amplifying both alleles in heterozygous cells lysed according to two different protocols. A total of 177 heterozygous cells from carriers of cystic fibrosis (CF) and haemoglobin C (HbC) were lysed using two different lysis buffers. Interestingly none of the cells that were lysed with sodium dodecyl sulphate/proteinase K showed any example of allele specific amplification failure whereas in those lysed by KOH/dithiothreitol it was present in 17.6 and 4.7% of the CF and HbC cells respectively. Our results suggest that the phenomenon of allele specific amplification failure is at least in part dependent on the lysis buffer used.      

NHS reforms and resource management: whither the hospital?

This paper considers whether resource management (RM) as currently constituted in the National Health Service (NHS) is likely to fulfil its aim of efficiency. For the individual hospital RM has two key features: changes in managerial structure and changes in information systems. The paper assesses the extent to which the hospital behavioural model that implicitly underlies RM can be judged to reflect well the actual behaviour of hospitals. It is noteworthy that in the RM literature there is no explicit statement about the assumed underlying behaviour of the NHS hospital. Here the author selects the Harris model of hospital behaviour as providing the best explanation of internal hospital organisation. Harris represents the two lines of authority, physicians and administrators (managers in the present-day NHS), as two firms within the hospital structure, each with its own managers, objectives and constraints, making this model particularly appealing as a basis for analysing RM. Using this model the paper concludes that RM alone and as currently constituted will not be successful in promoting efficiency, because the structural and cultural mechanisms put in place by RM will not sufficiently affect physician behaviour.     

Preferential coassembly of alpha4 and delta subunits of the gamma-aminobutyric acidA receptor in rat thalamus.

Pharmacological study of rat thalamic gamma-aminobutyric acidA (GABAA) receptors revealed the presence of two distinct populations, namely, diazepam-sensitive and diazepam-insensitive [3H]Ro15-4513 binding sites accounting for 94 +/- 2% (1339 +/- 253 fmol/mg protein) and 6 +/- 2% (90 +/- 44 fmol/mg protein) of total sites, respectively. Thalamic diazepam-insensitive sites exhibited a pharmacology that was distinct from diazepam-sensitive sites but comparable to that of the alpha4beta3gamma2 subtype of the GABAA receptor stably expressed in L(tk-) cells. Immunoprecipitation experiments with a specific anti-alpha4-antiserum immunoprecipitated 20 and 7% of total thalamic [3H]muscimol and [3H]Ro15-4513 sites, respectively. Combinatorial immunoprecipitation using antisera against the alpha4, gamma2, and delta subunit revealed that alpha4delta- and alpha4gamma2-containing receptors account for 13 +/- 2 and 8 +/- 3% of [3H]muscimol sites from thalamus, respectively. It also indicated that all delta subunits coexist with an alpha4 subunit in this brain region. In conclusion, our results show that in rat thalamus both alpha4betagamma2 and alpha4betadelta subtypes are expressed but alpha4betadelta is the major alpha4-containing GABAA receptor population.     

FIELD TRIAL OF Bacillus thuringiensis var israelensis PELLET FORMULATION IN THE CONTROL OF MOSQUITOES

In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control     

Gender and Ethnic Differences in Survival in a Cohort of HIV Positive Clients

Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.