Metastatic cancer to the ureter and kidney from malignant lymphoma. A review of the literature

Metastasis to the ureter may evolve by direct or indirect extension and invasion from the most common malignant tumors, such as breast, colon and lymphoma. A case of an unusual extension of metastatic infiltration to the ureter, kidney and other intra-abdominal and retroperitoneal structures is reported. Such a case has not been presented roentgenographically in the urologic or radiologic literature.     

Differential regulation of ceramide in lipid-rich microdomains (rafts): antagonistic role of palmitoyl:protein thioesterase and neutral sphingomyelinase 2

Cell differentiation and myelination involve a fine balance between stasis and programmed cell death, yet the genes that regulate this have not been clearly defined. We therefore studied two key gene products involved in oligodendrocyte plasma membrane lipid metabolism and their antagonistic role in ceramide-mediated cell death signaling. Overexpression of palmitoyl:protein thioesterase (PPT1; verified by Western blot of the V5-tagged protein and increased enzyme activity) resulted in decreased ceramide in the detergent-resistant microdomain (DRM, or raft) relative to cholesterol and sphingomyelin (SM). This PPT1 overexpression also resulted in protection against cell death induced by either staurosporine or C(2)-ceramide. In contrast, overexpression of neutral sphingomyelinase 2 (NSMase2; verified by Western blot of the FLAG-tagged protein and increased enzyme activity) resulted in increased membrane NSMase and increased ceramide in rafts relative to cholesterol and SM. The difference in SM and ceramide turnover was quantitated by [(3)H]palmitate pulse-chase labeling. Furthermore, when NBD-SM was added to cells, it was hydrolyzed by NSMase-transfected cells at more than twofold the rate in untransfected cells. NSMase2 overexpression enhanced cell death induced by staurosporine or C(2)-ceramide, in contrast to the protective effect of PPT1 overexpression. The presence of a fraction of both PPT1 and NSMase2 in rafts together with their substrates (palmitoylated proteins and SM, respectively) suggests a mechanism for dynamic palmitoylation/depalmitoylation of certain proteins in controlling cell death via NSMase activation.     

Community based trials and informed consent in rural north India

Disease control has increasingly shifted towards large scale, disease specific, public health interventions. The emerging problems of HIV, hepatitis, malaria, typhoid, tuberculosis, childhood pneumonia, and meningitis have made community based trials of interventions a cost effective long term investment for the health of a population. The authors conducted this study to explore the complexities involved in obtaining informed consent to participation in rural north India, and how people there make decisions related to participation in clinical research.     

Wear mechanisms in ceramic hip implants

The wear in hip implants is one of the main causes for premature hip replacements. The wear affects the potential life of the prosthesis and subsequent removals of in vivo implants. Therefore, the objective of this article is to review various joints that show lower wear rates and consequently higher life. Ceramics are used in hip implants and have been found to produce lower wear rates. This article discusses the advantages and disadvantages of ceramics compared to other implant materials. Different types of ceramics that are being used are reviewed in terms of the wear characteristics, debris released, and their size together with other biological factors. In general, the wear rates in ceramics were lower than that of metal-on-metal and metal-on-polyethylene combinations.     

Effect of Manilkara hexandra (Roxb.) Dubard against experimentally-induced gastric ulcers

Effects of the flavonoid rich fraction of the stem bark of Manilkara hexandra (Roxb.) Dubard, have been studied on ethanol, ethanol-indomethacin and pylorus ligated gastric ulcers in experimental animals. Oral administration of the ethyl acetate extract (extract A3) inhibited the formation of gastric lesions induced by ethanol in a dose dependent manner. The protective effect of extract A3 against ethanol induced gastric lesions was not abolished by pretreatment with indomethacin (10 mg kg(-1)). Further, extract A3 inhibited increase in vascular permeability due to ethanol administration. Extent of lipid peroxidation was significantly reduced in animals treated with extract. Extract A3 also inhibited the formation of gastric ulcers induced by pylorus ligation, when administered both orally and intraperitoneally. Moreover, pretreatment with extract A3 increased mucus production and glycoprotein content, which was evident from the rise in mucin activity and TC: PR ratio.     

A comparative study of cardiovascular stress during different swimming strokes

The study was aimed: (i) to compare maximum heart rate during exhaustive running (HRmasr) and swimming (HRmaxs), (ii) to compare heart rate (HR) in various modes of swimming-front crawl (FC), butterfly (BF), breast stroke (BRS) and back stroke (BS). HRmaxr (192.3 +/- 4.9 beats/min) of the swimmers (N = 7) was higher, although not significantly (P < 0.05), than their HRmaxs (183.7 +/- 3.8). Peak HR of the swimmers in FC, BF, BRS and BS (each of 100 m distance) were 179.9 +/- 7.2, 180.3 +/- 7, 178.6 +/- 6.2 and 177.3 +/- 5.4 beats/min respectively. Average HR in the respective events were 167.3 +/- 15.8, 166.6 +/- 14.1, 163.3 +/- 13.5 and 165.8 +/- 14.6 beats/min. Differences were not significant between any two modes, either in peak HR or mean HR. The results conclude that: (i) maximum HR in swimming is approximately 8 beats/min lower than maximal running and (ii) when the effort is maximum, cardiovascular stress remains unaltered in different swimming modes.     

Basic auditory processing skills and specific language impairment: a new look at an old hypothesis.

PURPOSE: To explore the sensitivity of children with specific language impairment (SLI) to amplitude-modulated and durational cues that are important for perceiving suprasegmental speech rhythm and stress patterns. METHOD: Sixty-three children between 7 and 11 years of age were tested, 21 of whom had a diagnosis of SLI, 21 of whom were matched for chronological age to the SLI sample, and 21 of whom were matched for language age to the SLI sample. All children received a battery of nonspeech auditory processing tasks along with standardized measures of phonology and language. RESULTS: As many as 70%-80% of children diagnosed with SLI were found to perform below the 5th percentile of age-matched controls in auditory processing tasks measuring sensitivity to amplitude envelope rise time and sound duration. Furthermore, individual differences in sensitivity to these cues predicted unique variance in language and literacy attainment, even when age, nonverbal IQ, and task-related (attentional) factors were controlled. CONCLUSION: Many children with SLI have auditory processing difficulties, but for most children, these are not specific to brief, rapidly successive acoustic cues. Instead, sensitivity to durational and amplitude envelope cues appear to predict language and literacy outcomes more strongly. This finding now requires replication and exploration in languages other than English.     

Acute Vitamin D Toxicity in an Infant

We report vitamin D toxicity in an infant following consecutive administration use of a large dose of vitamin D, causing symptomatic hypercalcemia, which was successfully managed with injectable calcitonin. However, the child developed bilateral medullary nephrocalcinosis which persisted 42 mon after the initial episode.