Tyrosine hydroxylase polymorphisms and bipolar affective disorder

A reported genetic association between bipolar affective disorder and DNA polymorphisms at the tyrosine hydroxylase gene is not confirmed by the present study. The combined allele frequencies in the patients, from studies published to date, are significantly different from the frequencies in the controls for the TY7/BglII polymorphism.     

Human melanoma-specific oncofetal antigen defined by a mouse monoclonal antibody

140.240, an IgG2a mouse monoclonal antibody raised against a cultured human melanoma cell line, was highly specific for melanoma cells as determined by direct and absorption analyses in a mixed hemadsorption assay. Supernatants of doubly cloned hybridomas producing antibody 140.240 reacted with all cultured and fresh melanomas tested but failed to react with a variety of carcinomas, sarcomas, lymphomas, leukemias and other tumors of neuroectodermal origin. This antibody did not react with B-lymphoid cell lines, ruling out HLA-DR specificity. Non-reactivity of antibody 140.240 with peripheral blood lymphocytes obtained from the donor of the immunizing melanoma line excluded the possibility of detecting histocompatibility antigens. Nevus cells were also non-reactive. However, antibody 140.240 did identify an antigenic determinant on tissue homogenates prepared from fetuses of 10–14 weeks' gestation. The antigen involved was shed by cultured melanoma lines and, by immunoprecipitation analysis of radiolabelled lysates, had a molecular weight of approximately 87kdal. Thus, the structure identified by monoclonal antibody 140.240 is a melanoma-specific oncofetal antigen.     

Preparation of the mineral phase of bone using ethylenediamine extraction

A detailed, efficient method of extracting mineral matter from bone tissue using a Soxhlet apparatus and anhydrous ethylenediamine is presented. The ethylenediamine solubilizes the organic portion, fat and protein, of the tissue with minor, if any, chemical or physical alteration of the mineral phase. After ethylenediamine treatment the sample is washed with cold water to eliminate the solvent. X-ray diffraction, density and chemical analyses and exchange studies have been used to monitor changes within the mineral matter during the extraction and washing procedures.

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Zusammenfassung Eine detaillierte, wirksame Methode wird dargelegt, mit welcher aus Knochengewebe die Mineralsubstanz mit Hilfe eines Soxhlet-Apparates mittels wasserfreiem Äthylendiamin extrahiert werden kann. Das Äthylendiamin löst den organischen Anteil — Fett und Protein — des Gewebes mit geringer oder überhaupt keiner chemischen oder physikalischen Veränderung der Mineral phase. Nach der Behandlung mit Äthylendiamin wird die Probe mit kaltem Wasser gewaschen, um das Lösungsmittel zu entfernen. Röntgen-Diffraktion, Dichte, chemische Analyse und Austausch-Studien wurden verwendet, um Veränderungen in der Mineralsubstanz während der Extraktions- und Waschvorgänge zu überwachen.

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Résumé Une méthode efficace et détaillée d'extraction de la matière minérale du tissu osseux à l'aide d'un appareil Soxhlet et d'éthylène diamine anhydre (ED), est décrite. L'éthylène diamine solubilise la portion organique (graisse et protéine) du tissu avec peu ou pas de modifications chimiques ou physiques de la phase minérale. Après traitement à l'éthylène diamine, la pièce est lavée à l'eau froide pour éliminer le solvant. La diffraction aux rayons X, la densité, les analyses chimiques et des études d'échange ont été utilisées pour étudier les modifications de la phase minérale pendant les procédés d'extraction et de lavage.

     

Thiazide diuretics and calcium metabolism

Thiazide diuretics reduce urinary excretion of calcium by about 40% in patients with intact parathyroid glands (normal parathyroid function or primary hyperparathyroidism). Despite equivalent sodium losses, thiazide diuretics do not lower calcium excretion in patients with hypoparathyroidism. Thiazide diuretics diminish hydroxyproline excretion by about 22%, and they do not affect 3′5′-cyclic AMP excretion in subjects with intact parathyroid glands. These findings, together with additional data in the literature, suggest that thiazides may potentiate the renal action of parathyroid hormone, resulting in retention of calcium and partial suppression of parathyroid hormone secretion.     

Effect of a silver device in preventing catheter-related infections in peritoneal dialysis patients: silver ring prophylaxis at the catheter exit study

Catheter-related infections remain a significant cause of method failure in chronic peritoneal dialysis (PD) therapy. Given the increasing antibiotic resistance, such nonpharmacological strategies as local silver devices attract more interest. To establish whether a silver ring device (designed by Grosse-Siestrup in 1992) mounted onto the PD catheter and placed at the exit site at skin level is effective in preventing exit-site and other catheter-related infections, a prospective 12-month, multicenter, controlled study stratified by diabetes status was conducted. The study subjects were assessed by an extensive structured inventory, including a broad spectrum of control variables, such as age, body mass index (BMI), Staphylococcus aureus carrier status, catheter features, mode and quality of PD therapy, comorbidity, and psychosocial rehabilitation. Ten experienced German outpatient dialysis centers (seven adult, three pediatric) participated in the trial. All eligible patients (n=195) from the study area without catheter-related infections during the ascertainment period were included (incidental subjects undergoing PD therapy for at least 3 months). The main outcome measures were the occurrence of first exit-site infections (primary study end point), sinus tract/tunnel infection, and peritonitis. Ninety-seven patients were assigned to the silver ring and 98 patients to the control group. Baseline characteristics of age, sex, proportion of pediatric and incidental patients, S aureus carrier status, and other variables were similar in both groups. The incidence of infections in the silver ring group versus the control group was as follows: 23 of 97 versus 16 of 98 patients had exit-site infections, 12 of 97 versus 12 of 98 patients had sinus tract/tunnel infections, 16 of 97 versus 18 of 98 patients had peritonitis, respectively. Kaplan-Meier analysis for the probability of an infection-free interval showed no statistical difference (log-rank test) between the two groups. Displacement of the silver ring contributed to study termination in 6% of the study group patients, including two patients with catheter loss. Univariate analysis and multiple logistic regression identified younger age (<50 years), low serum albumin level (<35 g/L), number of previously placed PD catheters, short cuff-exit distance (<2 cm), and S aureus nasal carriage as risk factors for the development of exit-site infections. In conclusion, our study does not show any benefit of the silver ring in preventing catheter-related infections in PD patients. Thus, prevention of infection-related method failure in PD still has to rely on conventional antibiotic treatment strategies and less so on alternative methods.     

Acute spinal cord injury: MR imaging at 1.5 T

Thirty-seven magnetic resonance (MR) imaging studies were performed with a 1.5-T magnet and surface coils in 27 patients with suspected spinal cord injuries. Imaging was performed 1 day to 6 weeks after injury. Cord abnormalities were seen with MR in 19 patients, while skeletal and/or ligamentous injuries were seen in 21 (78%). Three types of MR signal patterns were seen in association with cord injuries. Acute intraspinal hemorrhage was seen in five patients with cord injuries and demonstrated decreased signal intensity on T2-weighted images obtained within 24 hours of injury. Cord edema and contusion had high signal intensity on T2-weighted images and were observed in 12 cases with cord injury. Neurologic recovery, determined in 16 patients, was insignificant in patients with intraspinal hemorrhage; however, patients with cord edema or contusion recovered significant neurologic function. MR at 1.5 T is extremely useful in the diagnosis of acute cord injury and also demonstrates potential in predicting neurologic recovery.     

Invasive treatment methods in therapy and angiogenic sepsis

In 1850 patients with intravenous catheters, intravenous shunts and fistulas sepsis developed in 0.43%. Infection of the catheters and shunts was more frequent than sepsis development. The growth of microorganisms (Staphylococcus aureus, Gram-negative microbes) was noted during a bacteriological study of 300 removed catheters in 27.7%. Angiogenic sepsis was caused by Staphylococcus aureus. Peculiarities of the clinical picture of angiogenic sepsis were discussed. Its early diagnostic signs were described. Immunological changes in the patients with angiogenic sepsis were evaluated. The problems of pathogenesis and prevention of angiogenic sepsis were given due attention.