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Hepatic injury is one of the most common complications associated with cisplatin (CIS) use. Recently, liver protection lines are being discovered to stop the hepatic cell death due to inflammatory and apoptotic perturbations. l-arginine has protective effects in several models of liver injury. This study was designed to investigate the possible protective effect of l-arginine against CIS-induced acute hepatic injury in rats. Rats were divided into 4 groups: control, l-arginine, CIS, l-arginine + CIS. Liver function, oxidative stress, inflammatory cytokines, and apoptosis markers were assessed. l-arginine pretreatment protected the liver against CIS-induced toxicity as indicated by significantly alleviating the changes in liver function along with restoration of the antioxidant status. This finding was confirmed with the markedly improved pathological changes. l-arginine showed anti-inflammatory effect through the reduction of liver expression of iNOS, TNF-α, and NF-κß, which were ameliorated to significant levels. Furthermore, l-arginine administration downregulated the liver expression of the apoptotic marker, caspase-3. The results recommend l-arginine as a hepatoprotective agent against CIS toxicity. Mostly, this hepatoprotective effect of l-arginine involved anti-inflammatory and anti-apoptotic activities.

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(1)H MRS has great potential for the clinical investigation of childhood brain tumours, but the low incidence in, and difficulties of performing trials on, children have hampered progress in this area. Most studies have used a long-TE, thus limiting the metabolite information obtained, and multivariate analysis has been largely unexplored. Thirty-five children with untreated cerebellar tumours (18 medulloblastomas, 12 pilocytic astrocytomas and five ependymomas) were investigated using a single-voxel short-TE PRESS sequence on a 1.5 T scanner. Spectra were analysed using LCModel to yield metabolite profiles, and key metabolite assignments were verified by comparison with high-resolution magic-angle-spinning NMR of representative tumour biopsy samples. In addition to univariate metabolite comparisons, the use of multivariate classifiers was investigated. Principal component analysis was used for dimension reduction, and linear discriminant analysis was used for variable selection and classification. A bootstrap cross-validation method suitable for estimating the true performance of classifiers in small datasets was used. The discriminant function coefficients were stable and showed that medulloblastomas were characterised by high taurine, phosphocholine and glutamate and low glutamine, astrocytomas were distinguished by low creatine and high N-acetylaspartate, and ependymomas were differentiated by high myo-inositol and glycerophosphocholine. The same metabolite features were seen in NMR spectra of ex vivo samples. Successful classification was achieved for glial-cell (astrocytoma + ependymoma) versus non-glial-cell (medulloblastoma) tumours, with a bootstrap 0.632 + error, e(B.632+), of 5.3%. For astrocytoma vs medulloblastoma and astrocytoma vs medulloblastoma vs ependymoma classification, the e(B.632+) was 6.9% and 7.1%, respectively. The study showed that (1)H MRS detects key differences in the metabolite profiles for the main types of childhood cerebellar tumours and that discriminant analysis of metabolite profiles is a promising tool for classification. The findings warrant confirmation by larger multi-centre studies.

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AIMS: To explore short echo time (30 ms) 1 H magnetic resonance spectroscopy (MRS) in children with brain tumours and determine the contributions to the characterization of these tumours of the metabolites inositol/myoinositol and glutamate/glutamine, which are not visible at long echo times (135 or 270 ms). METHODS: Over a 12-month period 86 single-voxel MRS investigations were performed on 59 children with various brain tumours on a Siemens Symphony 1.5-T Magnetom using point-resolved spectroscopy and echo time of 30 ms. RESULTS: The procedure was well tolerated, and good-quality data were obtained. N-Acetyl aspartate (NAA)/Choline (Cho) and creatine (Cr)/Cho concentration ratios were significantly (p<0.001) lower in tumour (0.95 and 1.63, respectively) compared with non-involved brain (3.68 and 3.98, respectively) in all histological types. Inositol/Myoinositol (Inos)/Cho ratios were significantly (p<0.05) lower in untreated tumours (1.91) than in treated tumours (3.93) and in non-involved brain (3.32). Inos/Cho ratios were high in diffuse pontine gliomas and low in medulloblastomas and supratentorial primitive neuroectodermal tumours (p<0.01). Glutamate/Glutamine (Glut)/Cho ratios were high in grade 1 astrocytomas (6.4) and unbiopsied optic gliomas (9.84) but low in diffuse pontine gliomas (2.44). Lipids and macromolecules were present in most tumours but in low quantities in non-involved brain. CONCLUSION: Good-quality short echo time MRS data can be collected routinely on children with brain tumours. Inos and Glut levels show greater variability between tumour types than NAA, Cho and Cr present at long echo times, providing improved tumour characterization. Inos/Cho levels differ between untreated and treated tumours and may be useful for treatment monitoring.

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Various surface modifications have been applied to titanium alloy (Ti-6Al-4V) implants, in an attempt to enhance osseointegration; crucial for ideal prosthetic fixation. Despite the numerous studies demonstrating that peptide-modified surfaces influence in vitro cellular behavior, there is relatively little data reporting their effects on bone remodeling. The objective of this article was to examine the effects of chemically modifying Ti-6Al-4V surfaces with a common RGD sequence, a 15-residue peptide containing GRGDSP (glycine-arginine-glycine-aspartate-serine-proline), on the modulation of bone remodeling. The expression of proteins known to be associated with osseous matrix and bone resorption were studied during the growth of human bone-derived cells (HBDC) on these peptide-modified surfaces. HBDC grown for 7 days on RGD surfaces displayed significantly increased levels of osteocalcin, and pro-collagen Ialpha1 mRNAs, compared with the production by HBDC grown on the native Ti-6Al-4V. A pattern that was also reflected at the protein levels for osteocalcin, type I collagen, and bone sialoprotein. Moreover, HBDC grown for 7 and 14 days on RGD-modified Ti-6Al-4V expressed significantly higher level of osteoclast differentiation factors and lower levels of osteoprotegerin and IL-6 proteins compared with other surfaces tested. These results suggest that different chemical treatments of implant material (Ti-6Al-4V) surface result in differential bone responses, not only their ability to form bone but also to stimulate osteoclastic formation.

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We present the CT and B-scan sonographic findings in an infant with juvenile retinoschisis, a rare hereditary eye disease, which usually follows an X-linked recessive inheritance pattern.

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We assessed the relative roles of alcohol and infection with Helicobacter pylori in the pathogenesis of chronic gastritis in alcoholic patients. Helicobacter pylori was found in 14 of 18 alcoholics with dyspepsia and was associated with chronic antral gastritis. Gastric biopsy specimens were normal in four H pylori-negative alcoholics. Studies were repeated 3 to 4 weeks after controlled abstinence. There was no change in histologic findings during this period, indicating that alcohol itself was not the major causative agent. We then eliminated H pylori in 10 subjects by giving triple therapy (bismuth subsalicylate, amoxicillin, and metronidazole). Treatment for H pylori was associated with almost complete normalization of histologic findings. Four control subjects who received antacids alone showed no improvement. Dyspeptic symptoms in H pylori-positive patients significantly improved after elimination of this organism, whereas there was no change with antacid treatment.

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PIP: Large numbers of Indo-Fijian women are using marriage agencies and advertisements to find husband in Australia, New Zealand and Canada: this article investigates this new type of arranged marriage. Half of the Pacific island of Fiji are Indo-Fijians who are farmers, professionals, educated and prosperous, but have limited political, educational and land rights relative to the native Fijians. Some women pay $200-800 to a broker in Suva, Fiji; some read local newspaper ads and correspond with potential husbands. Most are divorced, school dropouts, unemployed or unmarriageable to peers in Fiji. Neither the women nor their families seem to object to their marrying a man who is considerably older, divorced, of another race or religion, or handicapped physically or socially. They hope to better their standard of living and procure visas for the rest of their family to migrate. Many Asian wives are specifically sought by Western men who want an exotic, docile woman for her personal service. Paradoxically, the Fijian brides have high expectations or romantic illusions, and hope to escape the servitude normal in their own families. Neither the Fijian women nor the Western men normally know or seek information about each others' cultures. Many of these marriages break down because of emotional and physical problems and unrealized expectations. The women's movement has criticized this phenomenon as exploitation of women, yet for many it is their only hope of escaping from arduous work, submission to Indo-Fijian husbands and their family, or their own family if they cannot marry or work. If their foreign marriage fails, they have the hope of more economic opportunities and a better welfare system in the new country.^ieng

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A survey of laboratory stocks of Culex tritaeniorhynchus Giles has uncovered the presence of four electrophoretic variants and one apparent null allele of amylase. Linkage experiments with heterozygous males indicate that amylase is sex-linked. The gene sequence is w (white eye) - Amy (amylase) - M (sex), and the recombination frequencies are: w - Amy = 6.02%, Amy - M = 1.35% and w - M = 7.37%.

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