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J Greene

Publications and source records attributed to J Greene.

At least 19 recordsLinked to original sources

The binding specificity of normal and variant rat Kupffer cell (lectin) receptors expressed in COS cells.

A receptor uniquely found on the surface of rat Kupffer cells was shown previously to bind oligosaccharides terminating in galactose, N-acetylgalactosamine, and fucose. To analyze further the binding specificity of the receptor, receptor-mediated adhesion of transfected COS cells to immobilized glycolipids of known structure was measured. The glycolipid Gb4Cer (GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1Cer) was the best ligand. Gb5Cer (GalNAc alpha 1-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1Cer) and LacCer (Gal beta 1-4Glc beta 1Cer) bound more weakly (five times less than Gb4Cer) and Gb3Cer (Gal alpha 1-4Gal beta 1-4Glc beta 1Cer), and g3Cer(GalNAc beta 1-4Gal beta 1-4Glc beta 1Cer) bound even more weakly (60 times less than Gb4Cer). Gangliosides did not support adhesion of transfected cells. The adhesion of COS cells transfected with plasmids encoding variants of the receptor was also examined. In each variant, either tryptophan 498 or 523, which are conserved in most C-type lectins, was replaced by one of several amino acids. Variants that retained binding activity had the same specificity as the normal receptor. Differences between variants were noted, however, in maximal levels of adhesion and these differences correlated with altered expression of the receptor variants in COS cells.

Acetylgalactosamine

Reproductive behavior and health in consanguineous marriages.

In many regions of Asia and Africa, consanguineous marriages currently account for approximately 20 to 50% of all unions, and preliminary observations indicate that migrants from these areas continue to contract marriages with close relatives when resident in North America and Western Europe. Consanguinity is associated with increased gross fertility, due at least in part to younger maternal age at first livebirth. Morbidity and mortality also may be elevated, resulting in comparable numbers of surviving offspring in consanguineous and nonconsanguineous families. With advances in medicine and public health, genetic disorders will account for an increased proportion of disease worldwide. Predictably, this burden will fall more heavily on countries and communities in which consanguinity is strongly favored, as the result of the expression of deleterious recessive genes. However, studies conducted in such populations indicate that the adverse effects associated with inbreeding are experienced by a minority of families.

Congenital Abnormalities

Penicillinase-producing Neisseria gonorrhoeae in a subset of nonemergent patients: I. A trend in the Washington, DC area.

A significant increase in penicillinase-producing isolates of Neisseria gonorrhoeae has been detected and documented in the District of Columbia. Currently, the prevalence of beta-lactamase isolates is approaching 50%, with the greatest number of cases being detected in the 18- to 23-year-old age group, in both males and females. Indicators suggest that this trend, which was first noted in 1987, will become more pronounced in the future. Ceftriaxone is now the first-line drug of choice in treating suspected gonococcal infections.

Adolescent

Effect of advanced age on p-aminohippurate-induced inhibition of renal tubular secretion in male Fischer 344 rats.

The effect of aging on glomerular filtration, effective renal plasma flow and on the responsiveness of the renal tubular anion secretory system to inhibition by 4-aminobenzoylglycine (p-aminohippurate, PAH) was examined in young (5-month) and old (22-month) Fischer 344 male rats. Plasma clearance, protein binding and renal extraction of [131I]o-iodohippurate, [125I]iothalamate and HPLC-purified [99mTc]mercaptoacetyltriglycine (MAG3), were used as in vivo probes of renal function. The effect of advanced age, without concomitant PAH, on the disposition of these markers was initially determined in ketamine anesthetized, temperature-maintained male rats, ages 5, 14 and 22 months by means of constant infusion clearance studies. Aging per se decreased (P less than 0.05) the kidney-weight normalized or body weight-normalized GFR and effective renal plasma flow rates. GFR values averaged 1.67, 1.43 and 1.32 ml/min per g kidney for the 5-, 14- and 22-month-old rats, respectively. Kidney- or body weight-normalized clearances of MAG3 and o-iodohippurate showed similar (25-27%) decreases, whereas the absolute values (ml/min) for GFR, o-iodohippurate and MAG3 clearance rates were not altered by aging. The effective filtration fraction, extraction ratio and plasma protein binding were also unchanged by advanced age. Overall, the age-related decreases in renal function were minimal in Fischer-344 rats, compared to other species. Differences in data normalization, species and gender account, in part, for discrepancies observed when comparing results in different studies on the effects of advanced age on renal function. Subsequently, we examined the effect of aging on the renal responsiveness to inhibition of tubular anion secretion using constant rate PAH infusion studies, adjusted for age-related changes in renal function. Aging did not alter PAH-induced inhibition of iodohippurate secretion. Inhibition of MAG3 elimination was more pronounced in the old rats compared to the young controls.

Aging

Oral mucosal lesions found in smokeless tobacco users.

The risk for oral mucosal lesions associated with use of smokeless tobacco among 1,109 professional baseball players during spring training in 1988 was investigated. Leukoplakia was very strongly associated with use of smokeless tobacco in this population of healthy young men. Of the 423 current smokeless tobacco users, 196 had leukoplakia compared to seven of the 493 nonusers (OR = 60.0, 95% CI = 40.5-88.8). The amount of smokeless tobacco used (in hours per day that smokeless tobacco was held in the mouth), recency of smokeless tobacco use (hours since last use), type (snuff versus chewing tobacco), and brand of snuff used were significantly associated with risk for leukoplakic lesions among smokeless tobacco users. Ninety-eight leukoplakic areas in 92 subjects were biopsied and examined microscopically. All lesions were benign, but one specimen had mild epithelial dysplasia. The long-term significance of leukoplakia in smokeless tobacco users and their relation to oral cancer is not clear.

Adult

Periodontal effects associated with the use of smokeless tobacco.

This report describes periodontal findings from a comprehensive study of smokeless tobacco use in professional baseball players. Subjects consisted of 1,094 players, coaches, and training staff of seven major league and their associated minor league teams. Before being examined, subjects completed questionnaires on patterns of smokeless tobacco use (validated by blood chemistry studies), rinsed their mouths under supervision, and were cautioned not to discuss their use of tobacco with the dental examiners. They then received a complete oral examination that included recording of all mucosal abnormalities, missing teeth, caries, extrinsic stain, attrition, Plaque Index, Gingival Index, pocket depth, attachment loss, and gingival recession. More than 50% of team members reported using smokeless tobacco, and 39% reported use during the current week. Among current week users, 46% had oral mucosal lesions, located primarily in the mandible at sites where the smokeless tobacco quid was placed. The use of smokeless tobacco was not necessarily associated with severe forms of periodontal disease, and the presence of poor oral hygiene and gingivitis in these users was not related to the development of oral lesions. However, sites adjacent to mucosal lesions in smokeless tobacco users showed significantly greater recession and attachment loss than in sites not adjacent to lesions in users or comparable sites in non-users.

Adult

Prognostic indicators in the initial presentation of Pneumocystis carinii pneumonia.

We prospectively evaluated 150 consecutive patients with Pneumocystis carinii pneumonia (PCP) as their sole initial manifestation of AIDS (group 1). Admission laboratory and radiographic criteria were analyzed for diagnostic and prognostic indicators and compared with those of patients presenting with non-PCP pulmonary manifestations of AIDS (group 2). Mean admission serum LDH level was 465 +/- 67 IU/L in PCP patients (group 1) and 211 +/- 28 IU/L in group 2 (p less than 0.01). Seventy-eight percent of PCP patients (117 of 150) survived. Comparing survivors with nonsurvivors, the mean admission LDH level was 394 +/- 45 vs 717 +/- 51 IU/L (p less than 0.01), and the mean P(A-a)O2 gradient was 42 +/- 6 vs 55 +/- 6 mm Hg (p less than 0.05). Serum LDH levels and P(A-a)O2 gradients have diagnostic and prognostic implications in patients with AIDS-related PCP.

Acquired Immunodeficiency Syndrome

How to beat the high pressure cost.

Low cost, enclosed, silicon wafer pressure transducers have recently been introduced on the market in physiological ranges. This paper describes one family of these devices and describes an electronic circuit to interface these devices to a chart recorder or other high-level recording device.

Blood Pressure Determination

Bias between enzymatic methods and the reference method for cholesterol.

Assaying 312 serum samples, we compared four enzymatic methods for serum cholesterol with the Reference Method (modified Abell-Kendall) of the Centers for Disease Control (CDC). The means for the aca, TDx, and SMAC methods (2.27, 2.27, and 2.24 g/L, respectively) were significantly higher (P less than 0.05) than those of the Reference Method and the RA-1000 method (2.19 and 2.18 g/L, respectively). The biased methods had positive proportional and (or) systematic biases. Results with these methods were 2.6% to 4.9% higher than with the Reference Method. The assigned concentrations of cholesterol in the calibration materials for the SMAC and aca agreed with those obtained by the Reference Method, but were lower for the TDx and higher for the RA-1000. These findings document positive biases for cholesterol with three enzymatic methods and suggest that misassignment of calibrators is not primarily responsible for the biases found with the aca and SMAC. It may, however, to be a significant factor for the TDx.

Autoanalysis

Two transcriptional activators, CCAAT-box-binding transcription factor and heat shock transcription factor, interact with a human hsp70 gene promoter.

We characterized the activity of a human hsp70 gene promoter by in vitro transcription. Analysis of 5' deletion and substitution mutants in HeLa nuclear extracts showed that the basal activity of the promoter depends primarily on a CCAAT-box sequence located at -65. A protein factor, CCAAT-box-binding transcription factor (CTF), was isolated from HeLa nuclear extracts and shown to be responsible for stimulation of transcription in a reconstituted in vitro system. DNase I footprinting revealed that CTF interacts with two CCAAT-box elements located at -65 and -147 of the human hsp70 promoter. An additional binding activity, heat shock transcription factor (HSTF), which interacted with the heat shock element, was also identified in HeLa extract fractions. This demonstrates that the promoter of this human hsp70 gene interacts with at least two positive transcriptional activators, CTF, which is required for CCAAT-box-dependent transcription as in other promoters such as those of globin and herpes simplex virus thymidine kinase genes, and HSTF, which is involved in heat inducibility.

Base Sequence

9-(1,3-Dihydroxy-2-propoxymethyl)guanine (ganciclovir) in the treatment of cytomegalovirus gastrointestinal disease with the acquired immunodeficiency syndrome.

9-(1,3-dihydroxy-2-propoxymethyl) guanine (ganciclovir) was used to treat 41 patients (median age, 37 years) with the acquired immunodeficiency syndrome and cytomegalovirus gastrointestinal infection. Sites of infection were the colon in 31, the esophagus in 5, the rectum in 4, and the small bowel in 1. Patients received ganciclovir, 5 mg/kg body weight, intravenously every 12 hours for 14 days. Clinical improvement was seen in 30 patients and virologic response in 32. Mainly hematologic toxicity occurred: moderate leukopenia (1000 to 1900/mm3) was seen in 7 patients and severe (less than 1000/mm3) in 1, and moderate neutropenia (500 to 1000/mm3) in 5 and severe (less than 500/mm3) in 1. A cutaneous rash developed in 2 patients. Median overall survival was 16 weeks (range, 2 to 56). Cytomegalovirus recurred in 13 patients; median time to recurrence was 9 weeks from the start of treatment. Ganciclovir may be effective in treating cytomegalovirus gastrointestinal disease in patients with the acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome