Mutational analysis of CDKN2 (MTS1/p16ink4) in human breast carcinomas

The CDKN2 gene that encodes the cell cycle regulatory protein cyclin-dependent kinase-4 inhibitor (p16) has recently been mapped to chromosome 9p21. Frequent homozygous deletions of this gene have been documented in cell lines derived from different types of tumors, including breast tumors, suggesting that CDKN2 is a tumor suppressor gene involved in a wide variety of human cancers. To determine the frequency of CDKN2 mutations in breast carcinomas, we screened 37 primary tumors and 5 established breast tumor cell lines by single-strand conformation polymorphism analysis. In addition, Southern blot analysis was performed on a set of five primary breast carcinoma samples and five breast tumor cell lines. Two of the five tumor cell lines revealed a homozygous deletion of the CDKN2 gene, but no mutations were observed in any of the primary breast carcinomas. These results suggest that the mutation of the CDKN2 gene may not be a critical genetic change in the formation of primary breast carcinoma.     

2-Chlorodeoxyadenosine therapy in advanced chronic lymphocytic leukaemia

The therapeutic potential of 2-chlorodeoxyadenosine (CdA) in patients with advanced chronic lymphocytic leukaemia (CLL) remains controversial with response rates in clinical trials ranging from 44 to 67%. This report describes our experience with CdA in 22 CLL patients having already undergone previous treatment. CdA was given by continuous intravenous infusion at a dose of 4 mg/m2/day for 7 days (4 patients) or as 2-h intravenous infusions at a dose of 5.6 mg/m2/day for 5 days (18 patients). Partial (n = 5) or complete (n = 2) response was obtained in 7 cases. As compared to unresponsive patients, responding subjects received CdA earlier in the course of their disease (mean interval between diagnosis and CdA therapy 58 vs 102 months), were less thrombocytopenic at initiation of CdA (mean platelet count 165 x 10(9)/L vs 81 x 10(9)/L) and experienced less severe neutropenia during the first course of therapy (mean minimal neutrophil count 1.55 x 10(9)/L vs 0.43 x 10(9)/L). None of 6 patients with CLL refractory to fludarabine responded to CdA. An evaluation of haematological toxicity during the first course of treatment showed grade 4 neutropenia (< 0.5 x 10(9)/L) in 7 cases and grade 4 thrombocytopenia (< 25 x 10(9)/L) in one of 19 cases where the platelet count was greater than 25 x 10(9)/L at initiation of CdA. In comparison with earlier reports, the present series of patients had received relatively heavy prior therapy, experienced more severe haematological toxicity and demonstrated a lower total response rate.     

Completeness of reporting of diagnosed HIV-infected hospital inpatients

To assess the completeness of human immunodeficiency virus (HIV) reporting among hospital inpatients whose records listed diagnostic codes for HIV infection but who did not meet the 1987 AIDS case definition, we conducted a statewide hospital study of admissions between January 1, 1986 and December 31, 1990. Of the 396 HIV-infected hospital inpatients identified, 313 (79%) had been reported to the State HIV Registry. HIV reporting was less complete for patients who were older and/or were blood product recipients. Of the 313 reported patients, 189 (60%) had been reported prior to their first hospital admission. Temporal improvements were noted in the completeness of HIV reporting among the hospital patients (1986: 65%; 1987: 81%; 1988: 64%; 1989: 82%; 1990: 86%; Chi square for linear trend 9.6, p < 0.01) and prior to their first hospital admission (1986: 31%; 1987: 34%; 1988: 49%; 1989: 64%; 1990: 72%; Chi square for linear trend 26.6; p < 0.01). Women were more likely than men to be reported prior rather than during or after their first hospital admission (71% vs. 55%; p < 0.01). Of the 155 patients with CD4+ T-lymphocyte test results, 41 had CD4+ counts < 200 mm3 and met the 1993 but not the 1987 AIDS case definition. In South Carolina most (79%) diagnosed, hospitalized, HIV-infected patients had been reported to the State HIV REgistry, with improvements in reporting occurring over time. Findings suggest that the 1993 AIDS case definition will improve our ability to monitor severe morbidity related to HIV.     

Respiratory failure in acute pancreatitis: the role of free fatty acids

Hypertriglyceridemia has been noted in patients with acute pancreatitis and respiratory failure. Utilizing an isolated, perfused, canine pulmonary lobe, the effect of triglyceride infusion on pulmonary function was evaluated. When heparin was used to anticoagulate the perfusion circuit, the addition of triglyceride to the autologous blood perfusate resulted in massive weight gain (226 gm), intrapulmonary shunting (36%), and a marked drop in pulmonary compliance (congruent to 50%). Heparin activates lipoprotein lipase, and therefore some triglyceride in the perfusate was lipolyzed with a resultant increase in serum free fatty acids (FFAs) to 253 mumole/dl. When anticoagulation of the perfusion circuit was accomplished by defibrinogenation with Arvin, the addition of triglyceride to the autologous blood perfusate caused minimal weight gain (28 gm), no intrapulmonary shunting, and only a slight decrease in pulmonary compliance (22%). Arvin has no effect on lipoprotein lipase, and the FFA level in the perfusate remained normal (less than 70 mumole/dl). Thus it appears that FFA release secondary to the action of pulmonary lipoprotein lipase on blood triglyceride is the important pathogenic step in the induction of respiratory failure in this model.     

Lack of effect on ovariectomy on the metabolism of vitamin D and intestinal calcium-binding protein in female rats

A 20-year-old woman lost all useful vision over a 2 1/2-month period as a result of a necrotizing and occlusive vasculitis of the retina. Treatment with prednisone, immunosuppressants, and aspirin was unsuccessful. No systemic manifestations of the disease were found and no cause was discovered. Kodachromes and fluorescein angiograms showed the progression in one eye from normal to near total retinal necrosis. The process began with a mild venous dilation and peripheral arteritis that progressed into an obliterative vasculitis with abrupt vessel dilation, hemorrhages, and retinal swelling. This was followed by necrosis and sloughing of the retina into the vitreous. Vitreous contraction and necrotic retina produced unrepairable retinal detachments.     

Characterization of benzodiazepine receptors in primary cultures of fetal mouse brain and spinal cord neurons

Primary cultures of fetal mouse brain and spinal cord were examined for the presence of binding sites for [3H]diazepam. Both brain and spinal cord cultures contain high affinity binding sites which resemble benzodiazepine receptors found in mammalian CNS with respect to both pharmacologic profile and response to exogenously applied GABA. These observations, coupled with the electrophysiologic properties of these cells suggest that primary cultures of fetal mouse brain and spinal cord may be valid models for studying the role and regulation of the benzodiazepine receptor.     

An information-retrieval system for classifying work in the field of cerebral asymmetry

A hierarchically-branching system is recommended for classifying published work in the field of cerebral asymmetry, and its rapid retrieval. It can readily accommodate partically everything published since 1965.     

Detection of apoptosis in human and rat ovarian follicles

OBJECTIVE: The purpose of this study was to determine whether cells acquired from individual human preovulatory follicles undergo apoptosis (physiologic cell death) and, if so, to correlate the degree of apoptosis with characteristics of the follicles or the oocytes derived from the follicles. METHODS: We devised a sensitive nonradioactive method for detecting apoptotic DNA fragmentation in small numbers of cells derived from rat atretic follicles and follicular aspirates of patients undergoing assisted reproductive technologies. RESULTS: Using this method, apoptotic DNA was detected in rat atretic follicles, with optimal detection at 10-100 ng. Furthermore, apoptotic DNA was detected in some, but not all individual human follicular aspirates from several patients, and was found in follicles that produced oocytes that fertilized and developed into embryos. CONCLUSION: Apoptosis occurs in cells from human ovarian preovulatory follicles and may be a normal physiologic process of the follicle during luteinization.