In situ expression of platelet-derived growth factor (PDGF-beta) during chronic rejection is abolished by retransplantation.

We have shown that Fischer 344-->Lewis renal allografts (ALLO) develop chronic rejection which is not detected in Lewis-->Lewis isografts (ISO). The progression of chronic rejection in ALLO can be reversed by retransplantation (RE-TX) of kidneys from ALLO back into syngeneic Fischer 344 recipients. The purpose of this study was to assess the in situ expression of PDGF-beta, a cytokine associated with wound injury, in ISO, ALLO, and RE-TX. In situ PDGF-beta mRNA expression in kidney sections was assessed early (8 weeks) and late (16 weeks) during the development of chronic rejection. Kidneys from ALLO were transplanted back into syngeneic Fischer recipients at 12 weeks and evaluated for PDGF-beta expression 12 weeks later. Differences in glomerular staining were graded quantitatively on a minimum of 25 glomeruli per section with grade 0, no positive cells in the glomerulus; grade 1, 1 or 2 positive cells; grade 2, 3 or more positive cells in a segmental distribution; and grade 3, > 4 positive cells of moderate intensity in a diffuse distribution. According to this grading system, glomerular PDGF-beta mRNA expression in isografts (N = 6) at 8 and 16 weeks after transplantation was 0.09 +/- 0.03 and 0.2 +/- 0.04, respectively. In allografts (N = 6), PDGF-beta mRNA was significantly higher (P < .001) for the same time periods, 1.28 +/- 0.6 and 1.89 +/- 0.08, respectively. In situ expression of PDGF in retransplants (N = 6) at 24 weeks, 0.07 +/- 0.02, was significantly diminished (P < .001) at 24 weeks compared to allografts at 8 or 16 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Tritium sampling and measurement.

Current methods for sampling and measuring tritium are described. Although the basic techniques have not changed significantly over the last 10 y, there have been several notable improvements in tritium measurement instrumentation. The design and quality of commercial ion-chamber-based and gas-flow-proportional-counter-based tritium monitors for tritium-in-air have improved, an indirect result of fusion-related research in the 1980s. For tritium-in-water analysis, commercial low-level liquid scintillation spectrometers capable of detecting tritium-in-water concentrations as low as 0.65 Bq L-1 for counting times of 500 min are available. The most sensitive method for tritium-in-water analysis is still 3He mass spectrometry. Concentrations as low as 0.35 mBq L-1 can be detected with current equipment. Passive tritium-oxide-in-air samplers are now being used for workplace monitoring and even in some environmental sampling applications. The reliability, convenience, and low cost of passive tritium-oxide-in-air samplers make them attractive options for many monitoring applications. Airflow proportional counters currently under development look promising for measuring tritium-in-air in the presence of high gamma and/or noble gas backgrounds. However, these detectors are currently limited by their poor performance in humidities over 30%.

Weighting criteria in the diagnosis of a personality disorder: a demonstration.

This study focused on how clinicians combine symptom information about narcissistic personality disorder (NPD) to make a diagnosis. A sample of 59 psychiatrists and clinical psychologists were asked to read and diagnose 20 case histories of which 6 cases had criteria for NPD embedded as sentences. The number of criteria and the face validity of the criteria were varied across case histories. Three models of how criteria might be combined to form a diagnosis were compared: the polythetic model, the additive model, and the weighting model. The results were most consistent with the weighting model.

Malignant sex and aggression: an overview of serial sexual homicide.

Serial murderers have attracted considerable attention in the popular press and criminal justice field, but scientific literature about these individuals is limited. This article provides an overview, from a psychiatric perspective, of serial sexual homicide, one type of serial killing. Characteristics of this type of murder and of these offenders are discussed. Defining qualities and diagnoses applicable to serial sexual killers are reviewed. Various etiologic theories are discussed, with emphasis on the role of fantasy and psychodynamic explanations. Governmental agencies involved in combating this type of crime, along with the role of mental health professionals in criminal profiling, are presented. Finally, the authors explore the reaction of society to this phenomenon.

Variations on the family resemblance hypothesis as applied to personality disorders.

Diagnosis and classification of the personality disorders is controversial and problematic. Diagnostic reliability is uneven because of overlapping of traits and the lack of clear boundaries between categories. This study demonstrates that personality disorder diagnosis is dependent on the total number of defining features. Clinicians tend to ignore the presence of conflicting features when making a diagnosis. A new research instrument, artificially created case histories that allow the specific manipulation of defining features (i.e., diagnostic criteria), is described.

Peritonitis secondary to dialysis tubing contamination among patients undergoing continuous ambulatory peritoneal dialysis.

Patients were asked to report all dialysis system contaminations occurring from December 1985 through May 1988 to the home training facility. There were 74 instances of peritoneal dialysis system contamination, 20 of which resulted in peritonitis. Prophylactic antibiotics were used in 48 of 54 episodes not resulting in peritonitis. Three cultures yielded gram-positive organisms without clinical peritonitis becoming evident. Fourteen of the 20 episodes of peritonitis had received antibiotics prophylactically. System contaminations were classified into tears or holes of the catheter at the adapter on the Tenckhoff catheter or at the tubing connection to the dialysate bag and breaks of the connecting devices from either dialysis catheter to dialysis tubing or dialysis tubing to dialysate bag. System contaminations accounted for 20 of the 333 episodes of peritonitis that occurred during this time. Identifying system contamination is useful because prophylactic antibiotic therapy may prevent peritonitis.

Differences in kidney donations between blacks and whites: a retrospective study.

The differences in patterns of kidney donation between whites and blacks were examined over a four-year period. A statistically significant difference in living-related kidney donation between blacks and whites was observed: blacks acted as living-related donors far less frequently than their white counterparts.