Development of intratesticular implants of rat pituitary primordia

Intratesticular grafts of pituitary primordia from 11-13-day-old rat embryos developed in 6 weeks into round nodules approximately 1 mm in diameter. The nodules were principally composed of well differentiated glandular and nervous tissues.     

Actinic reticuloid

Actinic reticuloid is a polymorphous dermatosis resulting from a photosensitivity to long wavelength ultraviolet light and occasionally also to visible light, often with clinical and histological resemblance to lymphoma. We describe a patient who is the second American case to be reported with this disease and review the literature. Actinic reticuloid must be distinguished from mycosis fungoides, polymorphous light eruption, persistent light reaction, and contact dermatitis.     

Pathogenesis of renal calculi in distal renal tubular acidosis. Possible role of parathyroid hormone

Elevated circulating levels of immunoreactive parathyroid hormone (PTH), hypercalciuria and renal calculi were found in 3 patients with distal renal tubular acidosis (RTA). Treatment with alkali resulted in a fall of PTH toward normal and a reduction in urinary calcium, but the frequency of urolithiasis was unchanged. In one patient in whom prolonged follow-up was possible, a subtotal parathyroidectomy was performed. This was followed by virtual cessation of stone formation despite persistence of the acidification defect. This study suggests that RTA may be associated with secondary hyperparathyroidism and that the consequent elevation in PTH may play a contributory role in the pathogenesis of renal calculi.     

The microanatomy of the alveolar duct of the human lung imaged by confocal microscopy and visualised with computer-based 3D reconstruction

The most widely accepted model of human lung alveolar duct systems is that they are constructed from central helical fibres between the turns of which lie alveolar opening. Experimental difficulties of handling and sectioning lung tissue have made it difficult to confirm this. Confocal laser scanning microscopy (CLSM) was therefore used to generate optical serial sections of the lung that were reconstructed in three dimensions and displayed using volume rendering techniques. From images of the reconstructions, a new structure is proposed in which alveolar ducts consist of collections of connected oval, twisted loop structures with eccentric openings.     

Chronic obstructive pulmonary disease: role of bronchiolar mast cells and macrophages

Chronic obstructive pulmonary disease (COPD) is considered to be caused in part by smoking-induced inflammation, but it is unknown which inflammatory cells within the small airways are associated with the obstruction. We investigated the inflammatory infiltrate in the small airways of 16 current or ex-smokers with COPD (FEV1 < or = 75% predicted) and 15 without COPD (FEV1 > or = 85% predicted) in pneumectomy specimens that were removed for lung cancer. Mast cells, macrophages, neutrophils, eosinophils, T cells, and B cells were identified using immunohistochemistry on formalin-fixed, paraffin-embedded specimens. These cells were quantified in the epithelium and the remainder of the airway wall. The number of mast cells and macrophages in the epithelium, but not in the remainder of the airway wall, was significantly increased in patients with COPD. Neutrophil and T cell numbers did not differ between the groups. Only few B cells and eosinophils were present in both groups. Smoking history, perioperative steroid usage, tumor localization, or reversibility in the FEV1 to salbutamol could not account for the observed differences. We conclude that the number of epithelial mast cells and macrophages is increased in the bronchioli in smokers with airflow limitation, suggesting a role in development of COPD.     

Herniated intervertebral disc without pain

The diagnosis of herniated intervertebral disc is often made in cases of radicular pain in the low back, the neck, or sciatica or brachialgia. Practitioners often call upon radiologic imaging to confirm this diagnosis. But on radiologic examination, such a herniation may consist of a bulge, protrusion, prolapse, extension, extrusion or sequestration of this disc. We define and illustrate these terms from the literature. We then review the radiologic studies of normal controls, who have never had sciatica, brachialgia or pain in the low back or neck. In over one-quarter of these controls, studies using the plain x-ray, CT scan, myelogram, and MRI show various radiologic signs of a herniated intervertebral disc. We therefore recommend that practitioners should not exclusively rely on radiologic imaging to confirm the clinical diagnosis of a herniated intervertebral disc.     

Expression of the retinoblastoma (RB) tumor suppressor gene inhibits tumor cell invasion in vitro

To determine if replacement of the retinoblastoma (RB) tumor suppressor gene could inhibit invasion of RB-defective tumor cells, the capacity of tumor cells to migrate or invade was quantitated by the Boyden chamber assay. The studies were done in a diverse group of stable RB-reconstituted human tumor cell lines, including those derived from the osteosarcoma and carcinomas of the lung, breast and bladder. The expression of the exogenous wild-type RB protein in these tumor cell lines was driven by either a constitutively active promoter or an inducible promoter. It was found that significantly more tumor cells from the parental RB-defective cell lines and the RB revertants than from the RB-reconstituted RB+ cell lines penetrated through the Matrigel (P<0.001, two-tailed t-test), although both RB+ and RB- cells migrated at approximately the same rate on uncoated polycarbonate filters in the Boyden chambers. Of note, the inhibition of invasiveness of various RB-defective tumor cells by RB replacement was apparently well correlated with suppression of their tumorigenicity in vivo. In contrast, although either functional RB or p53 re-expression effectively suppressed tumor formation in nude mice of the RB-/p53null osteosarcoma cell line, Saos-2, replacement of the wild-type p53 gene had much less impact on their invasiveness as compared to the RB gene. These studies provided an insight into the broader biological basis of the RB-mediated tumor suppression in RB-defective tumor cells.     

Practice trends of American urologists in the treatment of impotence, incontinence and infertility

PURPOSE: Trends of urologist practice patterns in evaluating and treating impotence, incontinence and infertility in the United States were assessed. MATERIALS AND METHODS: In July 1995 the executive interviewing branch of the Gallup Organization selected randomly and interviewed by telephone 533 practicing urologists in the United States who had provided urological patient care for more than 20 hours per week, practiced in 1994 and completed a urological residency program. RESULTS: Treatment of male sexual dysfunction and female urinary incontinence comprises a significant portion of the professional activity of United States urologists. However, evaluation and management of male infertility occupy a small portion of the average urological work load. While more than half of United States urologist office clinical laboratories were inspected in 1994, only 2% failed evaluation due to major deficiencies. CONCLUSIONS: Male sexual dysfunction and female urinary incontinence are major areas of urological practice in the United States but male infertility is not. Few United States urologist clinical laboratories failed inspection because of major deficiencies.     

Altered retinoblastoma and p53 protein status in non-small cell carcinoma of the lung: potential synergistic effects on prognosis

Routinely processed pathological specimens from 119 patients with stage I and II adenocarcinomas or squamous cell carcinomas were examined by immunohistochemical analysis for altered retinoblastoma (RB) and/or p53 protein expression. Absent RB nuclear staining (RB-) indicating loss of RB function occurred in 19 (16%) of the cases studied, whereas expression of a putative mutant p53 nuclear protein (p53(+)) was found in 54 (45%) of the tumors. The median survival was 39 versus 12 months for patients with RB+ and RB- tumors, respectively (P = 0.05 by log rank analysis). Similarly, the median survival was 41 months for patients whose tumors had no expression of mutant p53 (p53(-)) compared with 24 months for individuals with p53 (+) tumors (P = 0.01). These differences in survival, however, were not statistically significant by multivariate analysis. Nevertheless, individuals with RB-/p53(+) tumors had a significantly shorter median survival (12 months) than those with RB+/p53(-) tumors (41 months), as determined by both log rank and multivariate analyses (P = 0.005 and 0.03, respectively). In addition, 66 large cell carcinomas from all stages were examined. Again, a more significant difference in survival (48 versus 8 months) was found between patients with RB+/p53(-) versus RB-/p53(+) tumors (P = 0. 006). These results suggest that RB and p53 status might be used synergistically as prognostic factors in a subset of non-small cell lung carcinomas.