L1 knockout mice show dilated ventricles, vermis hypoplasia and impaired exploration patterns

L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.      

Effect of control of blood glucose on urinary excretion of albumin and beta2 microglobulin in insulin-dependent diabetes.

To study the effects of improved control of blood glucose on markers of renal glomerular and tubular function, we initially determined, by radioimmunoassay technics, urinary excretion rates of albumin and beta2 microglobulin in 17 nondiabetic subjects and in 43 insulin-dependent, clinically nonproteinuric diabetic patients. Duration of diabetes ranged from six months to 39 years, and the patients were studied while receiving conventional therapy. Mean urinary albumin excretion was significantly elevated in the diabetics, but beta2-microglobulin excretion rates were not different from those of the controls, suggesting that the increased albumin excretion was due to increased transglomerular loss of albumin. Seven patients with long-term diabetes (duration of six to 33 years), selected because of elevated albumin excretion, were studied before and during a continuous, subcutaneous insulin infusion for a period of one to three days. Urinary albumin excretion was significantly reduced during the insulin infusion, but mean beta2-microglobulin excretion did not change. Strict control of blood glucose, even in the short term, may reverse a functional renal abnormality in long-duration, insulin-dependent diabetes.     

Primary T cell lymphoma of salivary gland: a report of a case and review of the literature

Lymphoma of the salivary gland accounts for 5% of cases of extranodal lymphoma and 10% of malignant salivary gland tumours. Most primary salivary gland lymphomas are B marginal zone lymphomas arising on a background of sialadenitis associated with autoimmune disorders such as Sjorgen's syndrome. Primary T cell lymphoma of the salivary gland is rare. This report describes a case of primary T cell lymphoma arising in the parotid gland of an elderly white man, which was notable for its striking resemblance to a B cell extranodal marginal zone lymphoma. Immunohistochemistry and gene rearrangement studies confirmed the clonal T cell nature of the tumour. There was no molecular evidence of Epstein-Barr virus (EBV) infection of neoplastic or surroundings cells. Only 14 cases of primary T cell lymphoma of the salivary glands have been recorded in the literature, most being from the Orient and having extremely variable prognosis. Those with a T/natural killer cell phenotype are associated with EBV infection. This case highlights the fact that T cell lymphoma in the salivary gland can mimic closely the morphological features of B cell extranodal marginal zone lymphoma.     

An improved screening system for the early detection of congenital dislocation of the hip

A screening programme for congenital dislocation of the hip in which physiotherapists examine all neonates is described, together with the results over a 7-year period. All easily reducible dislocated and dislocatable hips are splinted within 2-5 days of birth. Subluxable or "slidey" hips are identified and followed up but not splinted. Risk groups are also identified and followed up. There was a progressive decrease in the number of late diagnosed cases, a result suggesting that even late-presenting acetabular dysplasia can be eliminated by neonatal screening.     

Prostate-cancer surveillance - a cost-effective strategy

The intention of a surveillance program to monitor prostate cancer patients is to detect recurrence of disease as soon as possible and institute therapy at the time of recurrence in order to improve the chance of cure or extend survival. We analyzed the cost of four surveillance programs for prostate cancer. As PSA levels are more sensitive than the bone scan, prostatic acid phosphatase and alkaline phosphatase, a surveillance program which utilizes these latter tests provides no additional clinically useful information beyond a PSA level and is costly. Adopting a strategy of eliminating these tests from a surveillance program would reduce national annual expense by approximately $1.5 billion in the year 2000.     

维生素D_3对报告载体荧光素酶表达的作用

目的：　研究１,２５－二羟维生素Ｄ３ 对结肠癌细胞系Ｃａｃｏ－２ 细胞中报告基因表达的作用,并探讨在报告载体ｐＧＬ２ 序列中存在潜在的抑制性维生素Ｄ应答元件（ＶＤＲＥ）的可能性。方法：　采用磷酸钙沉淀法将报告载体转染入Ｃａｃｏ－２ 细胞。Ｃａｃｏ－２细胞经不同浓度１,２５－二羟维生素Ｄ３ 处理后测定细胞裂解液中表达的荧光素酶活性。结果：　应用ｐＧＬ２ 报告载体时,当用ｐＳＧ５－ＶＤＲ表达载体共转染后,１,２５－二羟维生素Ｄ３显著地抑制Ｃａｃｏ－２ 细胞荧光素酶的表达（Ｐ＜ ０．０５）;而未使用该表达载体共转染则无抑制作用（Ｐ＞ ０．０５）。应用ｐＧＬ３ 报告载体时,不同浓度的１,２５－二羟维生素Ｄ３ 对ｐＬＧ３转染后Ｃａｃｏ－２ 细胞表达的荧光素酶活性均无显著抑制作用（Ｐ＞ ０．０５）,该作用不依赖是否存在有ｐＳＧ５－ＶＤＲ表达载体共转染。结论：１,２５－二羟维生素Ｄ３ 对报告载体ＰＧＬ２ 荧光素酶表达具有抑制作用,而对ｐＧＬ３ 则否;类似人类ＰＴＨ基因中的潜在抑制性ＶＤＲＥ存在于报告载体ｐＧＬ２,在ｐＧＬ３ 中该ＶＤＲＥ业已改变。     

Nutrient intake, adiposity, and diabetes.

To study the role of nutritional factors in the genesis of diabetes, estimations of blood sugar concentration, food intake, and adiposity (as body mass index; BMI) were carried out on three normal population samples--namely, 961 employees of Beecham Ltd, 1005 employees of the Greater London Council, and 1488 middle-aged male civil servants (Whitehall study). Blood sugar concentrations and indices of glucose tolerance correlated positively with the degree of adiposity but tended to be negatively correlated with total food energy intake and its component nutrients (total carbohydrate, sucrose, and fat). This inverse trend was largely accounted for by highly significant inverse correlations between food energy intake and adiposity, a relation found in both sexes and in all three population samples and which extended across the whole range of nutrient intake and BMI. These findings suggest that greater degrees of adiposity are associated with lower than average food energy intakes and hence lower total energy expenditures. The association of increased adiposity with low food energy consumption may indicate an underlying "low energy throughput" state, and it may be the mechanisms of this, as well as the obesity, that are responsible for disease.     

Mini-percutaneous nephrolithotomy

Standard percutaneous nephrolithotomy is highly effective for the removal of renal calculi. However, significant morbidity has been associated with this procedure. Consequently, many urologists inappropriately defer to a less effective procedure to reduce patient morbidity. This practice may increase the total number of procedures needed for treatment and result in a substantial increase in health care costs. Mini-percutaneous nephrolithotomy using a 13F ureteroscopy sheath is described to reduce the morbidity associated with standard percutaneous nephrolithotomy while maintaining its efficiency and effectiveness for stone removal. The indications and technique for mini-percutaneous nephrolithotomy and our results are summarized.     

Epidemic parenteral exposure to volatile sulfur-containing compounds at a hemodialysis center.

OBJECTIVE: To determine the cause of acute illness on August 30, 2000, among patients at an outpatient dialysis center (center A). DESIGN: We performed a cohort study of all patients receiving dialysis on August 30, 2000; reviewed dialysis procedures; and analyzed dialysis water samples using microbiologic and chemical assays. SETTING: Dialysis center (center A). PATIENTS: A case-patient was defined as a patient who developed chills within 5 hours after starting hemodialysis at center A on August 30, 2000. RESULTS: Sixteen (36%) of 44 patients at center A met the case definition. All case-patients were hospitalized; 2 died. Besides chills, 15 (94%) of the case-patients experienced nausea; 12 (75%), vomiting; and 4 (25%), fever. Illness was more frequent on the second than the first dialysis shift (16 of 20 vs 0 of 24, P < .001); no other risk factors were identified. The center's water treatment system had received inadequate maintenance and disinfection and a sulfurous odor was noted during sampling of the water from the reverse osmosis (RO) unit. The water had elevated bacterial counts. Volatile sulfur-containing compounds (ie, methanethiol, carbon disulfide, dimethyldisulfide, and sulfur dioxide) were detected by gas chromatography and mass spectrometry in 8 of 12 water samples from the RO unit and in 0 of 28 samples from other areas (P < .001). Results of tests for heavy metals and chloramines were within normal limits. CONCLUSIONS: Parenteral exposure to volatile sulfur-containing compounds, produced under anaerobic conditions in the RO unit, could have caused the outbreak. This investigation demonstrates the importance of appropriate disinfection and maintenance of water treatment systems in hemodialysis centers.     

A quality assessment tool to evaluate tocolytic studies

Over the past 15 years, the use of β-agonists has declined worldwide. Following the Royal College of Obstetricians and Gynaecologists guidelines in 2002, clinicians in the UK and beyond were faced with the dilemma of continuing to use β-agonists, desist from using tocolytic therapy completely or choosing to change to atosiban or calcium channel blockers (CCBs). While grade A level 1 evidence exists to show that atosiban is significantly more efficacious than placebo and significantly safer than β-agonists for the treatment of spontaneous preterm labour, the evidence for CCBs, such as nifedipine, is much less robust and no placebo-controlled trials have been performed. Published studies on nifedipine are largely investigator-led studies of small sample size, which lack sufficient power. As a result, most of the evidence has been based on meta-analyses of these studies, which look retrospectively at pooled data and are only as good as the quality of the studies included. In light of this, a tool was developed to produce a systematic review of studies on tocolytic effectiveness, which can and should be applied to all tocolytics and which considered both method- and topic-specific markers of quality. In the process of applying this tool to nifedipine, an extensive literature search identified 31 studies for a systematic review of the quality of nifedipine studies assessed by eight paired reviewers with wide experience in the subject of spontaneous preterm labour and preterm birth. Forty topic- and method-specific items of quality were assessed. The paucity of good quality studies of nifedipine used for the treatment of spontaneous preterm labour should be highlighted in meta-analyses or systematic reviews, which measure efficacy and should limit and influence the degree to which recommendations and guidelines are made on the basis of such studies.