Renal growth after neonatal urinary tract infection

This study presents the result of 12–21 years' follow-up in a group of children with neonatal urinary tract infection (onset within 1 month after birth) in whom early renal growth retardation was noted without concomitant classical renal scarring. In all cases the neonatal infection was diagnosed and treated within a few days of onset and the patients were closely supervised thereafter. Renal length, parenchymal thickness and area were measured at urography. At first follow-up (22 children, mean age 4.1 years) a significant reduction of renal parenchymal thickness was noted. Long-term follow-up (18 patients, mean age 17 years) demonstrated a normalization of renal size in the entire group, although less complete in the subgroup with reflux. There were two major findings in the present study. Firstly, renal growth retardation was seen after neonatal infection, both with and without reflux. Secondly, normalization of renal size in previously small kidneys was demonstrated, suggesting that growth retardation can be a reversible phenomenon. The tendency for such normalization was slightly more marked in children without reflux. Reduction of parenchymal thickness without calyceal deformity, therefore, does not necessarily mean irreversible damage, and differentiation between permanent scarring and temporary growth retardation can thus only be made at later follow-up, possibly not until after puberty. The demonstration of renal growth retardation in spite of early diagnosis and treatment emphasizes the great vulnerability of the kidney in the newborn.     

D1 dopamine receptors in the rat retina: effect of dark adaptation and chronic blockade by SCH 23390

Chronic administration of SCH 23390 (0.03 mg/kg s.c., three times daily), a selective D1 dopamine (DA) receptor blocker, markedly increased the [3H]SCH 23390 binding in the rat retina. As revealed by the Scatchard plot analysis of saturation data from retinal homogenates, chronic SCH 23390 increased the total number of binding sites by 34% when compared to tissue from solvent-treated rats but failed to change the apparent affinity of [3H]SCH 23390 for its binding sites. The up-regulation of [3H]SCH 23390 binding sites was paralleled by an increase in the sensitivity of retina DA-sensitive adenylate cyclase. In fact, DA (5 X 10(-6) M to 10(-4) M) produced a higher accumulation of cyclic AMP (from 58 to 128%) in the retina of SCH 23390-treated rats as compared to the accumulation (from 35 to 80%) found in tissue from solvent-treated rats. Since dark adaptation decreases dopaminergic function in the rat retina, the influence of environmental lighting on [3H]SCH 23390 binding and DA-sensitive adenylate cyclase activity was studied. After 4 h of dark adaptation the density of [3H]SCH 23390 binding sites was higher (32%) than that from light-adapted rats. On the other hand, dark adaptation failed to change the apparent affinity of [3H]SCH 23390 for its binding sites. Moreover, DA elicited a greater stimulation of adenylate cyclase activity in homogenates of retina from dark-adapted rats. Thus, the maximum adenylate cyclase response to DA resulted higher in the retina of dark-adapted rats (152%) than that found in the retina of light-adapted animals (97%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical and hormonal effects of chronic gonadotropin-releasing hormone agonist treatment in polycystic ovarian disease

Previously, we reported that short term administration of a highly potent GnRH agonist (GnRHa) for 1 month to patients with polycystic ovarian disease (PCO) resulted in complete suppression of ovarian steroidogenesis without measurable effects on adrenal steroid production. This new study was designed to evaluate the effects of long term GnRHa administration in PCO patients with respect to their hormone secretion patterns and clinical responses. Eight PCO patients and 10 ovulatory women with endometriosis were treated daily with sc injections of [D-His6-(imBzl]),Pro9-NEt]GnRH (GnRHa; 100 micrograms) for 6 months. Their results were compared to hormone values in 8 women who had undergone bilateral oophorectomies. In response to GnRHa, PCO and ovulatory women had rises of serum LH at 1 month, after which it gradually declined to baseline. In both groups FSH secretion was suppressed throughout treatment. Serum estradiol, estrone, progesterone, 17-hydroxyprogesterone, androstenedione, and testosterone levels markedly decreased to values found in oophorectomized women by 1 month and remained low thereafter. In contrast, serum pregnenolone and 17-hydroxypregnenolone were partially suppressed, and dehydroepiandrosterone, dehydroepiandrosterone sulfate, and cortisol levels did not change. Clinically, hyperplastic endometrial histology in three PCO patients reverted to an inactive pattern, and proliferative endometrium in two other PCO patients became inactive in one and did not change in the other. Regression of proliferative endometrial histology occurred in all ovulatory women. Vaginal bleeding occurred in all women studied during the first month of GnRHa administration, after which all but one PCO patient became amenorrheic. Hot flashes were noted by all ovulatory women and by four of eight PCO patients. All PCO patients noted subjective reduction of skin oiliness, and five had decreased hair growth. We conclude that in premenopausal women: 1) chronic GnRHa administration results in apparently complete persistent suppression of ovarian steroid secretion; 2) adrenal steroid secretion is not influenced directly or indirectly; and 3) its use may be helpful in the treatment of endometrial hyperplasia and ovarian androgen excess in women with PCO.     

Donor interleukin-4 promoter gene polymorphism influences allograft rejection after heart transplantation.

BACKGROUND: The cytokine interleukin-4 (IL-4) is secreted mainly by activated T lymphocytes and characterizes the T-helper 2 (Th2) sub-type. In transplantation Th2 cells are believed to induce graft tolerance. Previous studies revealed that patients with a relatively high frequency of IL-4 producing helper T lymphocytes (HTL) before heart transplantation (HTX) had no or less rejection episodes compared with patients with a low frequency of IL-4 producing HTL. Three single nucleotide polymorphisms (SNPs) have been identified in the promoter region of the IL-4 gene, which influence promoter strength. We investigated whether there was a correlation between SNP genotypes in the IL-4 promoter and heart failure, and rejection after HTX. METHODS: Seventy HTX patients, 61 donors, and 36 controls were genotyped for the 3 SNPs by sequencing. RESULTS: Of the SNPs at -285 and -81, only the C and A alleles, respectively, were found in this study. Both alleles were found for the -590 SNP. No relation between patient genotype of the SNP at -590 and heart failure and rejection was found. However, incidence of rejection was significantly lower in patients that received a donor heart with the T-positive genotype compared with patients that received a heart from a T-negative donor. Patients who had the T-negative genotype and received a heart from a T-positive donor, suffered significantly less from rejection than T-negative patients that received a T-negative donor heart. This was not significant in the T-positive patient group. CONCLUSIONS: This indicates that IL-4 production within the donor heart and by cells from the donor is important for reducing incidence of episodes of rejection.     

Stemmed femoral knee prostheses: Effects of prosthetic design and fixation on bone loss

Although the revision rates for modern knee prostheses have decreased drastically, the total number of revisions a year is increasing because many more primary knee replacements are being done. At the time of revision, bone loss is common, which compromises prosthetic stability. To improve stability, intramedullary stems are often used. The aim of this study was to estimate the effects of a stem, its diameter and the interface bonding conditions on patterns of the bone remodeling in the distal femur.

We created finite element models of the distal half of a femur in which 4 types of knee prostheses were placed. The bone remodeling process was simulated using a strain-adaptive bone remodeling theory. The amount of such remodeling was determined by calculating the changes in bone mineral density in 9 regions of interest from simulated DEXA scans.

The computer simulation model showed that revision prostheses tend to cause more bone resorption than primary ones, especially in the most distal regions. Predicted long-term bone loss due to a revision prosthesis with a thin stem equalled that around a prosthesis with an intercondylar box. However, strong regional differences were found- the stemmed prostheses having more bone loss in the most distal areas and some bone gain in the more proximal ones. A prosthesis with a thick stem led to an increase in bone loss. When the prosthesis-cement interface was bonded, more bone loss was predicted than with an unbonded interface. These results suggest that a stem which increases stability initially may reduce stability in the long term. This is due to an increase in stress shielding and bone resorption.     

CT-脑立体定向手术的临床应用

目的 评价CT－脑立体定向手术的临床应用价值。方法 应用CT－脑立体定向仪完成28例次脑立体定向手术，分析其临床诊疗效果。结果 立体定向活检术10例，术后病理诊断明确；定向开放手术12例，病灶一次切除；立体定向穿刺分流术6例，术后症状改善明显。手术均一次成功，无手术并发症。结论 CT－脑立体定向手术能精确定位，确定最佳手术路径，为颅内多种疾患的诊断和治疗提供新的方法。     

Prevalence of hepatitis B virus (HBV) markers and human immunodeficiency virus (HIV) in employees of a blood transfusion centre

Blood bank staff, 8 out of 25 (32%) have been exposed to hepatitis B virus (HBV) and the prevalence of HBV markers in blood bank employees handling high risk subjects show hepatitis B surface antigen (n = 1), hepatitis B surface antibody (n = 7), hepatitis B core antibody (n = 6) and combined hepatitis B surface antibody and hepatitis B core antibody (n = 6) seropositivity but all are negative to human immunodeficiency virus (HIV). Serum alanine aminotransferase was raised in the employees than normal subjects and it is suggestive of sub-clinical hepatitis. The employees of blood bank should be trained for proper handling of test materials and must be periodically monitored for HBV and HIV. Immunisation for HBV is mandatory only for the employees of transfusion centre which handles high risk subjects.     

Activation of glucocorticoid receptors and the effect of naloxone during hemorrhagic hypotension.

Evidence indicates that endogenous opioid peptides and glucocorticoids participate in the control of cardiovascular regulation during hemorrhagic shock. In the present study, we investigated a possible interaction between brain opioid peptides and adrenal corticosteroids regarding the control of arterial pressure during hemorrhage. The bleeding volumes required to lower arterial pressure to 80, 60 and 40 mmHg were studied in anesthetized sham-operated (SHAM) and adrenalectomized (ADX) rats. I.c.v. administration of 10 micrograms of naloxone resulted in a significant increase in the bleeding volume required to lower arterial pressure from 60 to 40 mmHg in SHAM animals, whereas no effect of naloxone was observed in ADX animals. Replacement therapy with a 100% corticosterone pellet (100 mg, s.c.), but not with a 12.5% corticosterone pellet (12.5 mg corticosterone and 87.5 mg cholesterol, s.c.), resulted in an effect of naloxone on the bleeding volume in ADX animals. The effect of replacement therapy could be inhibited by i.c.v. pretreatment with the synthetic glucocorticoid receptor antagonist, RU38486 (100 ng). These data suggest that (1) opioid mechanisms are involved in the regulation of blood pressure during hemorrhage, and (2) occupancy of glucocorticoid receptors is required for naloxone to exert its hemodynamic effect during hemorrhagic hypotension in ADX rats.     

4-Aminopyridine affects synaptosomal protein phosphorylation in rat hippocampal slices

Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II).     

Biochemical characterization of an aphthovirus type C3 strain Resende attenuated for cattle by serial passages in chicken embryos

We have compared several aspects of an aphthovirus strain attenuated for cattle (C3R-O/E) with the original strain (C3Res) from which it was derived after serial passages in chicken embryos. Biochemical differences detected by protein analysis in regular polyacrylamide gels (SDS-PAGE) and on electrofocusing gels (NEPHGE) suggest the presence of mutations throughout the genome. Changes were located in coat proteins VP1 and VP3 and in the polymerase precursor P100 (P3/ABCD). No other differences were found at the protein level by means of the techniques used. Polypeptide P100 of the attenuated strain showed a faster electrophoretic mobility in SDS-PAGE with respect to that of the wild-type strain, and the change seems to be located on its amino terminus half. Several functional differences were also found between the two viruses. Both strains grew equally well in BHK cells reaching roughly similar titers in plaque assays. However, the wild-type strain maintained its titer in cells of bovine origin (BK), whereas the titer of C3R-O/E strain decreased approximately one log in this cell system; moreover, plaques elicited by the attenuated strain were much smaller than the ones produced by C3Res. A diminution in the rate of RNA synthesis induced by C3R-O/E in BK cells compared with that of the wild-type strain was also detected; this trait was not observed in BHK cells. A delay in the kinetics of RNA synthesis was also detected in this strain. The virus yield of attenuated strain in BK cells was four times lower than in BHK cells.