Alterations in the superoxide dismutase gene of an isoniazid-resistant strain of Mycobacterium tuberculosis.

Genetic analysis of a set of six Mycobacterium tuberculosis strains differing in virulence for the guinea pig revealed an altered restriction enzyme fragmentation pattern associated with the superoxide dismutase (SOD) gene in a low-virulence, isoniazid-resistant strain. In addition, it was found that the SOD enzyme produced by the isoniazid-resistant strain differed in its electrophoretic mobility from the SOD of other M. tuberculosis strains. Detailed analysis of these strain-specific differences showed that the restriction fragment length polymorphism resulted from the presence of a copy of a repetitive element 552 bp upstream of the SOD gene and that the anomalous electrophoretic mobility arose from a single nucleotide change, resulting in replacement of an aspartic acid residue by histidine in the SOD enzyme of the isoniazid-resistant strain. Possible relationships between genetic changes and strain-dependent differences in virulence are discussed.     

An epidural abscess due to resistant Staphylococcus aureus following epidural catheterisation

We report a case of abscess formation after epidural analgesia, a rare complication that developed in our patient 13 days after placement of a thoracic epidural catheter for patient controlled analgesia. Culture of the pus grew methicillin-resistant Staphylococcus aureus . Although early diagnosis and rapid management have been reported to yield a satisfactory outcome, the case we describe ended in severe sequelae.     

Molecular analysis of HLA-DRB1 polymorphism in north-east Spain.

The DRB1* polymorphism in 941 randomly selected individuals from the Umbilical Cord Blood Bank of Barcelona (92.75% of Spanish origin) was determined by sequence-based typing. The HLA profile was similar to that of other Mediterranean populations, with DRB1*0701 and *0301 being the most frequent alleles. This may be a consequence of the mixture of alleles as a result of migration from contiguous geographical areas.     

Copper deficiency during parenteral nutrition: a report of four pediatric cases.

The standard of care for patients with cholestasis (direct bilirubin >or=2 mg/dL) while receiving parenteral nutrition (PN) solutions is to reduce or discontinue the copper and manganese. The repercussions of this action have not been studied. Two adult case reports document low serum copper levels associated with clinical symptoms of copper deficiency after the removal of copper from their PN solutions. We now describe the first known series of pediatric patients to develop copper deficiency after copper was removed from their PN solutions.     

Central opioid receptors differentially regulate the nalmefene-induced suppression of ethanol- and saccharin-reinforced behaviors in alcohol-preferring (P) rats.

The exact opioid-sensitive receptors participating in EtOH-seeking behaviors remains unclear. Previous studies have reported higher densities of micro-opioid receptor binding in the nucleus accumbens (NACC) of P relative to NP rats; however, no differences were seen in delta-receptor binding. In contrast to the NACC, substantially lower levels of micro-receptor binding have been observed in the ventral tegmental area (VTA) of both P and NP rats, albeit no line differences have been observed. In the present study, opioid receptors in the NACC, VTA, and hippocampus were evaluated for their capacity to regulate both EtOH- and saccharin-motivated behaviors in the genetically selected alcohol-preferring (P) rat. To accomplish this, nalmefene, an opiate antagonist with preferential binding affinity for the micro-opioid receptor was unilaterally or bilaterally infused during concurrent availability of 1 h daily EtOH (10% v/v) and saccharin (0.025 or 0.050% w/v) solutions. Rats performed under a two-lever fixed ratio (FR) schedule in which four responses on one lever produced the EtOH solution, and four on a second lever produced the saccharin solution. The results demonstrated that when responding maintained by both EtOH and saccharin are matched at basal levels, unilateral (1-60 microg) or bilateral (0.5-10 microg) microinjections of nalmefene into the NACC produced selective dose-dependent reductions on responding maintained by EtOH. Unilateral (40, 60 microg) and bilateral (10 microg) VTA infusions were also observed to selectively reduced EtOH responding; however, greater nalmefene doses were required and the magnitude of suppression on EtOH responding was markedly less compared with the NACC. The greater sensitivity of nalmefene to suppress EtOH responding in the NACC is likely due to the greater number of opioid receptors in the NACC relative to the VTA. Only bilateral infusion of the 40 microg dose in the NACC and VTA suppressed responding maintained by both EtOH and saccharin. In contrast, intrahippocampal infusions dose dependently suppressed EtOH- and saccharin-maintained responding over a range of doses (1-20 microg). The present study provides evidence that nalmefene suppresses EtOH-motivated behaviors via blockade of opioid receptors within the NACC and VTA, and under various dose conditions both reinforcer and neuroanatomical specificity can be observed.     

A Synergistic Effect Between PG490-88 and Tacrolimus Prolongs Renal Allograft Survival in Monkeys

This study was undertaken to determine if PG490-88 and tacrolimus (Tac) act synergistically to prevent renal allograft rejection in monkeys and to explore possible mechanisms of synergy between these agents. MHC-mismatched renal allografts were transplanted into cynomolgus monkeys after bilateral nephrectomy. Recipients were divided into the following groups: (i) no treatment; (ii) PG490-88 (0.03 mg/kg); (iii) Tac (1 mg/kg); (iv) PG490-88 (0.01 mg/kg) + Tac (1 mg/kg) and (v) PG490-88 (0.03 mg/kg) + Tac (1 mg/kg). Through synergy PG490-88 and Tac inhibited anti-CD3/PMA-induced T-cell proliferation and IFN-gamma expression in vitro. Tac monotherapy only marginally prolonged survival (27 +/- 3.2 days), while the combination of PG490-88 and Tac significantly prolonged graft survival to a median of 99 days (PG490-88 at 0.03 mg) and 38.5 days (PG490-88 at 0.01 mg/kg). Prolonged survival correlated with inhibited IgM production as well as reduced T-cell infiltration, IL-2 protein expression and NF-AT/NF-kappaB activity. We conclude that PG490-88 and a subtherapeutic dose of Tac significantly prolong renal allograft survival in monkeys through the synergistic inhibition of T-cell activation and a decrease in IFN-gamma production and NF-AT/NF-kappaB activity.     

IgA nephropathy and polycystic kidney disease

We report a patient with polycystic kidney disease, advanced renal failure, and nephrotic-range proteinuria. Kidney biopsy revealed IgA nephropathy with lesions of focal and segmental glomerular sclerosis. This association had not been previously described and is probably coincidental. This case supports the assumption that the nephrotic-range proteinuria observed in some polycystic patients could be the consequence of another superimposed glomerular disease. This glomerulopathy can worsen the course of azotemia in these patients.     

Iron nutrition in childhood malignancy

Status of iron nutrition along with demographic, anthropometric, dietary, and biochemical parameters were recorded in 98 pediatric cancer patients at the time of referral. Dietary intake in each patient was analyzed for calories, protein, and iron. Blood specimens were analyzed for hemoglobin (Hgb), hematocrit (Hct), iron, total iron-binding capacity (TIBC), transferrin, and ferritin. Dietary intake measures were assessed according to each subject's Recommended Dietary Allowance (RDA). The results were compared among three diagnostic groups, namely, benign, solid tumor, and hematopoietic. The nutrient lowest in intake was iron. The overall measures revealed significant differences between the benign and hematopoietic groups in all parameters except TIBC and transferrin. A correlation coefficient of 0.55 (p less than 10(-5) between transferrin and TIBC was generated in our patients. Significant differences were noted for ferritin in the acute lymphocytic leukemia (p = 0.0001) and lymphoma (p = 0.0007) groups when compared with the benign group. A correlation coefficient of 0.55 (p less than 10(-5) was generated in our patients. A 3-month follow-up assessment was conducted in order to document the effects of therapy. Tumor response and progression was compared to changes in ferritin levels from baseline to follow-up. Our results support the literature, that ferritin is a sensitive tumor marker in various malignancies.     

Histologic evaluation of radiofrequency ablation in renal cancer.

AIM: To report on the histologic evaluation of renal tumors after intraoperative radiofrequency ablation (RFA) performed immediately before surgical nephrectomy. MATERIALS AND METHODS: Ten patients with renal tumors were studied. All tumors were confirmed to be renal cell carcinoma before radio frequency ablation treatment. All specimens were stained with hematoxylin and eosin and nicotinamide adenine dinucleotide (NADH). RESULTS: Mean tumor size was 29 mm (range 14 to 48 mm). Of the 10 tumors 5 were completely devitalized with a treatment margin ranged from 1 to 20mm. One tumor needed two treatment sessions. No complication related to radiofrequency treatment was recorded. CONCLUSIONS: Our data indicate that RFA can completely destroy renal tumors. However, in our study, complete tumor cell death was obtained only in 50% of cases. More studies are needed to ensure that is technique is an effective and reproducible treatment.