Correlation of clinical and manometric abnormalities of rectal function following chronic radiation injury

Continuous fluid-inflation proctometrograms were performed in men with the symptoms of chronic radiation proctitis and in age and sex-matched control subjects (n = 10). Rectal volumes and compliance were measured. There was a significant reduction in the rectal volumes at sensory threshold, constant sensation and maximal tolerance and in rectal compliance (P less than 0.01). Comparable pressure measurements did not demonstrate significant differences. The maximum tolerable volume, symptomatic and sigmoidoscopic scoring correlated to rectal compliance (r = 0.77, -0.8, -0.73; P less than 0.01, less than 0.01, less than 0.02, respectively). Reduction in volume and compliance is often not obvious radiologically. Histological evidence suggests that smooth muscle hypertrophy and myenteric plexus damage are contributory.     

Multiple cerebral aneurysms associated with left-sided inferior vena cava and hemiazygos continuation: a case report

A case of multiple saccular cerebral aneurysms in association with a left-sided inferior vena cava and hemiazygos continuation is presented. To our knowledge, this association has not previously been recorded in the literature.     

Reproductive toxicity of 2,4-dinitrotoluene in the rat

The present study was undertaken to evaluate the effects of the chemosterilant 2,4-dinitrotoluene (DNT) on the rat testis. Adult male rats were fed control, or 0.1%, or 0.2% DNT for 3 weeks. An ultrastructural study of the testes was performed, serum was assayed for testosterone and gonadotropins, and sperm reserve count was determined. A marked change in Sertoli cell morphology was found after 3 weeks of 0.2% DNT exposure. Varying sized vesicles associated with swollen mitochondria and distended endoplasmic reticulum were visible in cells from DNT-treated animals. Circulating levels of follicle stimulating hormone and luteinizing hormone were increased in 0.2% DNT-treated animals. Reduced weights of the epididymides and decreased epididymal sperm reserves were observed in DNT-treated animals. These results indicate that DNT is capable of inducing testicular injury, of directly or indirectly disturbing pituitary function, and of exerting a toxic effect at the late stages of spermatogenesis. These findings suggest that a locus of DNT action is the Sertoli cell, resulting in both inhibition of spermatogenesis and changes in testicular-pituitary endocrine activity.     

Primary actinomycotic lung abscess

A case of recurrent massive haemoptysis in whom primary actinomycotic lung abscess was diagnosed following right pneumonectomy is reported.     

Molecular and genetic analysis of URA5 transformants of Cryptococcus neoformans.

Cryptococcus neoformans var. neoformans ura5 mutants were transformed with linearized or circular plasmids containing the C. neoformans orotidine monophosphate pyrophosphorylase gene. Following electroporation, randomly isolated transformants were analyzed for the mitotic and meiotic stability of uracil prototrophy. All stable transformants tested showed nonspecific ectopic integration. Uracil prototrophy in these transformants was stable through meiosis. Some of the stable transformants showed integration of both URA5 and vector sequences, while others lacked any vector sequences. Unstable transformants exhibited the presence of an autonomously replicating plasmid which had undergone significant sequence rearrangement. The autonomously replicating plasmid in the transformants was observed to be the same size or smaller than the transforming plasmid, was maintained in a linear form, and had acquired a genomic sequence(s) with homology to a sequence(s) on all the chromosomes. The conservation of a 300-bp sequence at the 5' end of the URA5 gene was observed in all the rearranged plasmids. These results suggest mechanisms of plasmid maintenance in C. neoformans that are different from those reported for other yeasts. The ura5 mutant was significantly less virulent than the wild type. The transformants did not recover virulence regardless of prototrophic stability.     

Alcohol Abuse in Asian Americans

Asian Americans are proportionately the fastest growing minority in the United States. Once considered a model minority, recent studies have suggested that Asians have a fairly high prevalence of alcoholism. The authors present epidemiological data from the few available surveys involving the Asian American community. An important consideration is that the term “Asian American” does not represent a homogenous group. It comprises people from many countries, several major religious groups, various socioeconomic levels, and different lengths of time and levels of acculturation in the United States. The presence of aldehyde dehydrogenase (ALDH2) deficiency also represents a relevant biological difference in some subgroups. This heterogeneity makes it difficult to encompass all relevant parameters in any one study, but each of these factors clearly affects the rates and expressions of alcohol use, and they all represent important considerations for treatment. Culturally sensitive and/or bicultural programs are indicated for the proper treatment of this population.     

P-glycoprotein inhibitors and their screening: a perspective from bioavailability enhancement.

Drug efflux pumps like P-glycoprotein (P-gp) and multidrug resistance (MDR) proteins were recognized to possess functional role in determining the pharmacokinetics of drugs administered by peroral as well as parenteral route. Advancements in molecular biology, to some extent, had revealed the structure, localization and functional role of P-glycoprotein and its mechanism of drug efflux. Broad substrate recognition by this protein and clinical implications of its inhibition has revolutionized cancer chemotherapy leading to design and development of novel P-glycoprotein inhibitors. In the recent times, the application of these inhibitors in improving peroral drug delivery has gained special interest. Inhibition of P-glycoprotein improves intestinal absorption and tissue distribution while reducing the substrate metabolism and its elimination. Eventually, various screening methodologies have been developed for determining the activity of P-glycoprotein, kinetics of drug transport and identification of substrates and inhibitors. In the present review, techniques used for screening P-glycoprotein inhibitors and the scope of these inhibitors in optimizing peroral drug absorption and pharmacokinetics are discussed along with a brief introduction to P-glycoprotein, its physiological function and active role in extrusion of drugs.