Effect of subchronic aflatoxin exposure on growth and progression of Ehrlich's ascites tumor in mice

The present investigation was undertaken to assess whether aflatoxin B1 (AFB1) has any modulatory effect on the growth and progression of Ehrlich's ascites tumor (EAT) in mice or not. Male Swiss albino mice were treated with 0, 70, 350 and 700 micrograms AFB1/kg body weight in 0.2 ml corn oil on alternate days, orally, for two weeks. Treated animals were challenged with 1 x 10(6) cells of Ehrlich's ascites tumor. Animals were monitored for the appearance of palpable tumor, body weight gain as a measure of tumor burden, mortality profile and tumor cell population. Some parameters of cell mediated immunity (CMI), humoral immunity and non-specific immunity were also studied in aflatoxin treated animals in order to find out the mechanism of action of AFB1 on host immunity. It was observed that AFB1 treatment resulted in an early appearance of tumor, enhanced mortality, appreciable increase in body weight gain and EAT cell population following tumor challenge, in comparison with the control animals. Aflatoxin treatment caused suppression of CMI including an impairment of macrophage function, while humoral immunity was not much affected. It may be concluded that impaired CMI and macrophage function might be contributing to the increased growth of EAT in the AFB1 treated animals. Our findings may be relevant in that when a host is exposed to aflatoxins concomitantly with other carcinogens and cancer causing situations.     

Aneurysmal bone cyst of the hyoid.

Aneurysmal bone cyst is a rare lesion usually of the long bones, well documented in the literature. It is a cystic, osteolytic vascular tumour, replete with giant cells and fibrous septa, yet devoid of endothelial lining. It has been reported in the larynx and maxillary sinus. This appears to be the first report of an aneurysmal bone cyst occurring in the hyoid bone.     

Changes in sexually transmitted disease rates after HIV testing and posttest counseling, Miami, 1988 to 1989.

OBJECTIVES. The effects of posttest counseling on acquisition of sexually transmitted diseases in patients at a large urban sexually transmitted disease clinic were studied. METHODS. Comparisons were made of the percentage of patients who had a positive gonorrhea culture (or any sexually transmitted disease) in the 6 months before and after human immunodeficiency virus (HIV) counseling and testing. RESULTS. For 331 patients counseled about a positive HIV test, the percentage with gonorrhea was 6.3 before and 4.5 after posttest counseling (29% decrease). For 666 patients counseled about a negative test, the percentage with gonorrhea was 2.4 before and 5.0 after posttest counseling (106% increase). With any sexually transmitted disease as the outcome, patients who tested positive for HIV had a 12% decrease and patients who tested negative had a 103% increase after counseling. CONCLUSIONS. HIV counseling and testing was associated with a moderate decrease in sexually transmitted diseases among patients who tested positive for the virus, but risk increased for patients who tested negative. This suggests a need to improve posttest counseling in this clinic and to assess the effects of counseling and testing in other clinics.     

Osteoclasts from medullary bone of egg-laying Japanese quail do not express the putative calcium 'receptor'.

The present study reports the contrasting effects of extracellular calcium ([Ca2+]e) elevation on cytosolic free calcium levels ([Ca2+]i) of osteoclasts, freshly isolated either from medullary bone of the egg-laying Japanese quail or from rat cortical bone. [Ca2+]i was measured in single osteoclasts using the Ca(2+)-sensitive fluorochrome, Indo-1. We found that elevation of [Ca2+]e failed to induce a rise of [Ca2+]i in quail osteoclasts, whilst causing an elevation of [Ca2+]i in rat osteoclasts. The calcium ionophore, ionomycin, led to a sustained elevation of [Ca2+]i in both cell types. These findings suggest that osteoclasts isolated from egg-laying quail do not possess the calcium sensor or 'receptor' that appears to be vital for the survival and function of rat osteoclasts.     

Uncoupling of receptor-mediated cellular responses by ionic lithium

The propensity of ionic lithium to interfere with the coupling of receptors to guanine nucleotide binding proteins (G-proteins) has only recently been investigated using rat cortical membranes. In the present study we have used intact isolated osteoclasts to investigate lithium-induced uncoupling of the receptor-mediated actions of calcitonin. All actions of calcitonin on the osteoclast were abolished by ionic lithium. We believe that the cation prevents signal transduction by inhibiting G protein-receptor interaction, the first step in intracellular signalling.     

Sexual abuse histories and sequelae in female psychiatric emergency room patients

The charts of 100 nonpsychotic female patients in a psychiatric emergency room were reviewed to locate references to history of sexual molestation: 50 charts were selected at random from emergency room files, and 50 charts had been written by clinicians asked to query abuse history. A substantially higher rate of sexual abuse was found for patients who had been directly asked about sexual molestation (70%) than for the random sample (6%). Further analysis linked molestation history to suicidality, substance abuse, sexual difficulties, multiple psychiatric diagnoses, and axis II traits or disorders--especially borderline personality. Severe abuse and multiple abusers best predicted psychiatric sequelae.     

Percutaneous angioplasty of internal mammary artery graft stenosis: case report and discussion

Percutaneous transluminal coronary angioplasty (PTCA) was successfully used for the first time in 1977. With experience, its application broadened to include multiple lesions, complex anatomical stenoses, multiple vessels, and saphenous vein aorto-coronary bypass grafts. This case demonstrates successful internal mammary graft angioplasty with continued long-term (eight months) success, documented angiographically.     

Development and performance of a highly sensitive carboxyl-terminal-specific radioimmunoassay of calcitonin gene-related peptide

The calcitonin genes encode a small family of peptides: the circulating hormone calcitonin; its flanking peptide, katacalcin; and a third novel peptide, calcitonin gene-related peptide (CGRP). CGRP is a potent vasodilator and a major circulating product from the calcitonin genes; it may be a physiologically important regulator of blood flow in humans. High concentrations of circulating CGRP are found in medullary thyroid carcinoma. We report the development and validation of a highly sensitive (detection limit 500 amol per tube) radioimmunoassay of CGRP involving a high-affinity antibody directed against the carboxyl terminus of the molecule and a highly pure tracer. The assay is precise, robust, and reproducible, and is therefore a potentially useful analytical method for studying the normal and abnormal physiology of this peptide.     

Assessment of occupational benzene exposure in petrol filling stations at Rangoon

An occupational health survey was conducted on workers, who inhale petrol fumes which contain low concentrations of benzene, at petrol filling stations in the city of Rangoon, Burma. To evaluate the exposure to benzene, urinary phenol (which is a principal metabolite of absorbed benzene) was measured in workers at petrol filling stations and in a control group of healthy male adults. The survey revealed that the urinary phenol content of workers exposed to petrol fumes was significantly higher than that of workers who were not exposed.