Effects of Ethanol Exposure during the Third Trimester Equivalent on Neuron Number in Rat Hippocampus and Dentate Gyrus

An artificial rearing procedure was used to expose neonatal rats to a formula containing 3.74% ethanol during postnatal days 4 through 10. This treatment produced a mean blood ethanol concentration of 379.8 +/- 17.3 mg/dl. When the pups were killed on the afternoon of postnatal day 10, brain weight to body weight ratio in the ethanol-exposed rats was reduced 22.4% and 21.5% compared to suckle and pair-fed controls, respectively. Ethanol exposure also resulted in a 16% reduction of neurons in hippocampal field CA4, compared to controls, but did not produce deficits in fields CA1 or CA3. There was also a 10% increase in the number of neurons (a population of cells in the midst of a proliferative phase at the time of the exposure) in the granule cell layer of the dentate gyrus. The ethanol exposure did not affect cell size in any of the four neuron populations measured. These results suggest, that within the dose and timing parameters examined, ethanol exposure during the third trimester equivalent appears to be preferentially harmful to specific populations of developing neurons.     

Effects of radiation on ovarian function in long-term survivors of childhood acute lymphoblastic leukemia: a report from the Childrens Cancer Study Group

The Childrens Cancer Study Group has assessed serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and pubertal development in 97 long-term female survivors of childhood acute lymphoblastic leukemia (ALL). All patients received identical induction and maintenance therapy with either 18 or 24 Gy of radiation therapy (RT) to one of the following fields: cranial, craniospinal, or craniospinal plus 12 Gy abdominal RT including the ovaries. Thirty-six percent (35 patients) were found to have above normal levels of FSH and/or LH. The percentages of elevated values for RT fields were 93% for craniospinal plus abdominal RT, 49% for craniospinal RT, and 9% for cranial RT (P less than .001). A dose-response relationship was observed between 18 Gy and 24 Gy in females receiving only craniospinal RT (P = .01). Craniospinal plus abdominal RT and abnormal FSH/LH levels were significantly associated with lack of pubertal development and delayed onset of menses. Duration of maintenance chemotherapy was not associated with abnormal gonadotropin levels or the development of secondary sexual characteristics. Additional follow-up of this cohort is needed to establish the ultimate pubertal development and fertility of these patients.     

Management of bacterial peritonitis and exit‐site infections in continuous ambulatory peritoneal dialysis*

SUMMARY: Peritonitis and exit‐site infections remain the most important limitations to the delivery of continuous ambulatory peritoneal dialysis (CAPD). Contamination of the peritoneum, from endogenous or exogenous sources, is responsible for most peritonitis episodes. Patients usually present with a cloudy bag, although other causes should be distinguished. Clinical suspicion of peritonitis should be followed rapidly by microbiological examination and empirical treatment. Microbiological confirmation allows for subsequent treatment based on sensitivities. Other interventions such as catheter removal may be appropriate in some patients. Exit‐site infections should also be identified and treated early. Peritonitis may be further prevented by adequate exit‐site care, hygienic methods, and techniques to minimise early contamination of the exit site. Mupirocin may also have a role in preventing infections caused by Staphylococcus aureus.     

Melioidosis. Forgotten, but not gone!

Melioidosis, infection by the soil bacterium Pseudomonas pseudomallei, has the potential for prolonged latency with recrudescence into an acute, often fulminating, and fatal infection. Although the organism is never found in North America, infection is endemic in areas of southeast Asia, and populations of service personnel exposed during the Vietnam war and southeast Asian immigrants are at risk of severe recrudescent disease. Diagnosis, however, has been missed or delayed because of lack of familiarity with this disease. We present a case of recrudescent melioidosis that illustrates the difficulties encountered in diagnosis and treatment. This case involves a 76-year-old Vietnam veteran who presented with melioidosis of the bone 18 years after exposure to the organism and 10 years after a missed diagnosis of latent pulmonary disease. This case illustrates the protean nature of latent infection and the difficulty of selecting successful antibiotic therapy.     

Dissociation of spatial navigation and visual guidance performance in Purkinje cell degeneration (pcd) mutant mice.

Spatial learning in rodents requires normal functioning of hippocampal and cortical structures. Recent data suggest that the cerebellum may also be essential. Neurological mutant mice with dysgenesis of the cerebellum provide useful models to examine the effects of abnormal cerebellar function. Mice with one such mutation, Purkinje cell degeneration (pcd), in which Purkinje cells degenerate between the third and fourth postnatal weeks, were evaluated for performance of spatial navigation learning and visual guidance learning in the Morris maze swim-escape task. Unaffected littermates and C57BL/6J mice served as controls. Separate groups of pcd and control mice were tested at 30, 50 and 110 days of age. At all ages, pcd mice had severe deficits in distal-cue (spatial) navigation, failing to decrease path lengths over training and failing to express appropriate spatial biases on probe trials. On the proximal-cue (visual guidance) task, whenever performance differences between groups did occur, they were limited to the initial trials. The ability of the pcd mice to perform the proximal-cue but not the distal-cue task indicates that the massive spatial navigation deficit was not due simply to motor dysfunction. Histological evaluations confirmed that the pcd mutation resulted in Purkinje cell loss without significant depletion of cells in the hippocampal formation. These data provide further evidence that the cerebellum is vital for the expression of behavior directed by spatial cognitive processes.     

Psychoactive mushroom use in Koh Samui and Koh Pha-Ngan, Thailand.

This paper presents the results of recent ethnomycological exploration in southern Thailand. Field observations, interviews and collection of fungi specimens were carried out primarily on two islands, Koh Samui and Koh Pha-ngan, situated in the western region of the Gulf of Siam. Some fieldwork was also conducted in the northern Thai province of Chiang Dao and in the southern Thai province of Surat Thani. During five separate excursions (1989-90), observations were made of occurrence, harvesting, use, and marketing of psychoactive fungi by local Thai natives (males and females, adults and children), foreign tourists, and German immigrants. The first records of psychoactive Psilocybe subcubensis and Copelandia dung fungi in Thailand are presented in this paper. These fungi exhibited intense bluing reactions when handled, indicating the presence of psilocybin and/or psilocin. Seven collections of Psilocybe cubensis (Earle) Singer and/or Psilocybe subcubensis Guzman and four collections of Copelandia sp. were harvested and sun-dried for herbarium deposit. These fungi are cultivated or occur spontaneously, often appearing in the decomposed manure of domesticated water buffalo (Bubalus bubalis) and at least three different species of cattle (Bos indicus, B. guarus, and B. sundaicus). The psychoactive fungi are cultivated in clandestine plots, both indoors and outdoors, in the uplands and villages on Koh Samui by both Thai natives and some foreigners. The sale of psychoactive fungi directly to tourists and to resort restaurants for use in edible food items such as omelettes and soups is discussed in detail. The preparation and sale of mushroom omelettes adulterated with artificial hallucinogens in some restaurants is also discussed. In addition, the marketing of items such as hand painted T-shirts, post cards, and posters bearing mushroom related motifs in Thailand is described.