Modeling the effects of health status and the educational infrastructure on the cognitive development of Tanzanian schoolchildren.

This paper models the proximate determinants of school attendance and scores on cognitive and educational achievement tests and on school examinations of over 600 schoolchildren from the Control group of a randomized trial in Tanzania, where children in the Intervention group heavily infected with hookworm and schistosomiasis received treatment. The modeling approach used a random effects framework and incorporated the inter-relationships between school attendance and performance on various tests, controlling for children's health status, socioeconomic variables, grade level, and the educational infrastructure. The empirical results showed the importance of variables such as children's height and hemoglobin concentration for the scores, especially on educational achievement tests that are easy to implement in developing countries. Also, teacher experience and work assignments were significant predictors of the scores on educational achievement tests, and there was some evidence of multiplicative effects of children's heights and work assignments on the test scores. Lastly, some comparisons were made for changes in test scores of treated children in the Intervention group with the untreated children in the Control group.     

Guidelines for Trials of Behavioral Treatments for Recurrent Headache, First Edition: American Headache Society Behavioral Clinical Trials Workgroup

Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache.     

Brain abscess in the 1980s

Brain abscess was reviewed in 24 patients admitted to University Hospital, Nottingham over a period of 3 years. Chronic ear infection was the most common predisposing factor, but in 11 patients the focus of infection remained unknown. CT scanning, carried out in all patients, was negative in one patient with clinical signs of meningitis. Polymicrobial and anaerobic infections were common. Actinomyces species were isolated in mixed culture from seven patients; in five the abscess was located in the cerebellum. Therapy was most often a combination of surgical drainage and antimicrobial therapy with beta-lactam agents and metronidazole. Evidence suggests that cefotaxime may offer a suitable alternative to chloramphenicol and benzylpenicillin in the treatment of brain abscess.     

Homologous testis transplantation in dogs

There is growing interest in the possible use of homologous testis transplantation for the treatment of anorchia and male infertility. In order to test the surgical and immunological feasibility of this therapy, three series of experimental studies of homologous testis transplantation were carried out in dogs. In the first pilot study, four beagles from the same litter were transplanted using microsurgical techniques for end-to-end anastomosis of the testicular vessels and the vas deferens. These dogs received cyclosporin A (CyA) for 3 months after transplantation. The longest functional graft survival in this series was 163 days, strongly suggesting that long-term survival of a homologously transplanted testis graft is possible. A second series of operations was performed on ten mongrel dogs. The same surgical technique was employed and the series was divided into three groups. Group 1 received CyA monotherapy, group 2 a combination of CyA and prednisolone, and group 3 received no immunosuppression. The average graft survival time in this series was 18 days, significantly less than the 71 days in the first series. The dogs in group 2, however, had graft survival times that were three times longer than those in the other two groups, suggesting that CyA in combination with prednisolone yields the best graft survival. In the third series, five littermates received a testis graft after castration. Immunosuppression was achieved by administration of CyA and prednisolone for 3 months. In three out of five animals, the graft survived until the immunosuppressive therapy was suspended. Histological biopsies of the graft 3 months after transplantation showed the same maturation of sperm cells as in the control testis of the same dog. The results of the last series suggest that long-term survival of homologously transplanted testis grafts in dogs is, indeed, possible with the aid of CyA and prednisolone. Received: 14 August 1996 Received after revision: 21 March 1997 Accepted: 24 April 1997     

Recombination between separate MYC amplification structures in COLO320 cells

Cytogenetically visible gene amplification structures can consist of arrays of amplicons presumably formed by secondary “rearrangements” following amplicon formation. The structural evolution of gene amplification sites in tumor cells suggests that complex secondary structures may have some selective advantage in the tumor cell environment. Although secondary amplicon rearrangements are a hallmark of the gene amplification process, little is known about the mechanics of this process. COLO320 neuroendocrine tumor cells carry two different types of amplified MYC oncogene sequences, one type with an intact MYC gene and the other with a rearranged “chimeric” MYC gene. We have studied various clonal subpopulations of COLO320 cells and identified regions within and downstream of the MYC locus that are unique to each amplicon type. Using double-label fluorescence in situ hybridization with DNA probes unique to each amplicon type, we have observed that both chromosomal and extrachromosomal MYC amplicon arrays in COLO320 cells frequently consist of heterogeneous mixtures of each MYC amplicon type. Our results suggest that the two MYC amplicon types of COLO320 cells were formed simultaneously but independently, and that double minute chromosomes observed in COLO320 cells were formed by intermolecular homologous recombination secondary to amplicon formation. © 1993 Wiley-Liss, Inc.     

Albuterol Delivery by Metered-Dose Inhaler With a Pediatric Mechanical Ventilatory Circuit Model

Study Objective . To determine albuterol delivery by metered-dose inhaler (MDI) in an in vitro pediatric mechanical ventilatory circuit model. The influence of a spacing device, endotracheal tube (ETT) diameter and length, and air humidity was also investigated. Design . An albuterol MDI canister was connected to an AeroVent spacer or Airlife MDI adapter and ETT 4.0, 5.0, or 6.0 mm at commercially available and equal lengths. The ETT tip was attached to an in-line filter holder with a 1-μm type A/E glass fiber filter. Ventilator settings were fractional concentration of inspired oxygen 50%, tidal volume 250 ml, inspiratory:expiratory (I:E) ratio 1:3, rate 25 breaths/minute, temperature 35°C, and a decelerating flow pattern. Ten albuterol canisters were activated two times each (total 2000 μg) into dry (4.0-, 5.0-, and 6.0-mm ETT) and humidified air (4.0- and 6.0-mm ETT) and repeated in triplicate. Percentage MDI output was determined by weighing the filter before and after drug administration (balance sensitivity 10 μg). Significant differences (p≤0.05) among the groups with and without a spacer and in dry and humidified air were determined by ANOVA with Scheffe's multiple comparison test. Multiple regression was used to determine significant associations between ETT diameter and length and delivery. Main Results . With the AeroVent spacer in humidified air, delivery with the 4.0- and 6.0-mm ETT was approximately 2.3% and 5%, respectively. The spacer and dry air significantly improved delivery. Conclusions . In humidified air, the dose of albuterol by MDI with an AeroVent spacer should be doubled for children intubated with 6.0-mm ETT, and four puffs administered for every one puff desired for 4.0-mm ETT. The results of this investigation should prove useful in initial clinical trials of albuterol MDI in ventilator-dependent infants and children.     

Uhthoff's symptom in multiple sclerosis

A case report is presented in which a patient's initial complaint is of blurred vision after exercise (Uhthoffs symptom). Visual acuity and colour vision were found to be reduced after exercise. Additional neurological signs included homonymous scotomata and delayed visual evoked and somatosensory responses. Magnetic resonance imaging demonstrated multiple abnormal lesions in the brain. The significance of this symptom and its relationship to multiple sclerosis are discussed.     

Weight gain in first-episode psychosis.

OBJECTIVE: To examine the extent of weight gain in the first year of treatment in an early psychosis program. METHOD: Subjects were 114 individuals who had experienced a first episode of psychosis and had completed 1 year in a comprehensive first-episode program. Weight and body mass index were calculated on entry to the program and at 6 and 12 months. Most of the subjects were all being prescribed second-generation antipsychotics. RESULTS: Significant increases in mean weight were observed in these young individuals over the course of the first year of treatment. CONCLUSIONS: If we are to work toward optimum treatment for first-episode subjects then potential weight gain needs to be addressed at the beginning of treatment and monitored during treatment.     

Criteria for the notification of childhood tuberculosis in a high-incidence area of the western Cape Province

The medical records of 124 children notified from Ravensmead Clinic, Parow, as having tuberculosis during 1987 were reviewed in order to determine the strength of the evidence on which the diagnosis was made. Arranging the diagnostic criteria in an hierarchical manner, as suggested by the World Health Organisation, the cases were categorised as suspect, probable or confirmed. Twenty-five were suspect cases (20%), 89 probable cases (72%) and the remaining 10 confirmed cases (8%). These findings indicated that notifications from the clinic were being made in accordance with internationally accepted practice. The use of the WHO approach for the categorisation of childhood tuberculosis cases is recommended for both clinical and epidemiological purposes.