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R Fink

Publications and source records attributed to R Fink.

At least 19 recordsLinked to original sources
PubMed1992

Ethanol inhibits interferon-gamma secretion by human peripheral lymphocytes.

Clinical and epidemiological evidence exists that subjects who chronically abuse alcohol are disposed to infections and certain types of cancer. In vitro inhibition of mitogen-induced lymphocyte proliferation has been shown suggesting a direct immunosuppressive effect of ethanol. Using human peripheral blood mononuclear cells we could demonstrate in vitro for the first time that even low ethanol concentrations of 6 and 12.5 mM significantly inhibit spontaneous and mitogen-induced secretion of interferon-gamma. This effect was more pronounced with lower mitogen stimulation and it increased in a dose dependent manner when higher ethanol concentrations were used. Inhibition of cell proliferation as measured by 3H-thymidine incorporation did not parallel the inhibition of interferon-gamma secretion. As this lymphokine exerts a great number of immunostimulating effects, diminished secretion might well contribute to the immune defect observed in alcoholics.

Alcohol Drinking↗
PubMed1991

Anemia and postoperative apnea in former preterm infants.

To examine the association between anemia and postoperative apnea in former preterm infants, 24 former preterm infants of less than 60 weeks postconceptual age undergoing inguinal hernia repair were studied. A hematocrit of at least 25% was required for study participation. General endotracheal inhalational anesthesia, supplemented with neuromuscular blockade and controlled ventilation, was used. No barbiturates or opioids were administered. Respiratory pattern and heart rate were recorded for at least 12 h postoperatively using an impedance pneumograph. Tracings were analyzed for evidence of apnea, periodic breathing, and/or bradycardia by a pulmonologist unaware of the hematologic profile of the infant. Nineteen patients had a hematocrit of 30% or greater (group 1). Their mean (+/- standard deviation [SD]) gestational age was 33.5 +/- 2.7 weeks and postconceptual age 45.5 +/- 4.6 weeks. Five infants had a hematocrit less than 30% (group 2). Their mean gestational age (+/- SD) was 32.4 +/- 3.2 weeks and postconceptual age 43.6 +/- 5.5 weeks. Anemic infants had an 80% incidence of postoperative apnea versus 21% in infants with a normal hematocrit (P less than .03). In the infants who developed postoperative prolonged apnea and/or bradycardia, a prior history of apnea was equally present in both groups (21% in group 1 and 20% in group 2). This study shows that anemia in former preterm infants can be associated with an increased incidence of postoperative apnea.

Anemia↗
PubMed1991

Adenoma-carcinoma sequence of the large bowel.

Fifty-two surgically removed large bowel specimens and 3 colonoscopically removed polyps with mucosal carcinomas were studied. Among 36 frank colorectal carcinomas, six (17%) had a focus of adenomatous remnant. The average size of carcinomas without adenomatous remnant was 56.0 mm and of those with adenomatous remnant was 44.3 mm. Four (67%) of 6 submucosal carcinomas and all of 4 mucosal carcinomas showed an adenomatous remnant. The average size of submucosal carcinomas was 17.7 mm and that of mucosal carcinomas was 16.3 mm. The smaller and less advanced the carcinoma, the more likely it was to show an adenomatous remnant, suggesting that carcinomas arise in adenomas and destroy surviving benign tumour as they grow. Coexisting adenomas were seen in 19 of 46 neoplasm-bearing patients (41%) and 1 of 9 patients (11%) without neoplasms. Average sizes of adenomas with moderate and mild atypia were 13.0 mm and 8.2 mm respectively, which were smaller than the sizes of submucosal and mucosal carcinomas. Although the numbers were small, these findings support the concept of adenoma-carcinoma sequence. Twenty-one flat elevations were collected during the study. Ten were neoplasm (9 adenomas and an early carcinoma), ten were metaplastic polyps and one was a histologically normal mucosal protrusion. The atypism of 10 flat adenomas increased with increasing size, as with ordinary adenomas. As 10 of 55 adenomas (18.2%) were flat adenomas, which are difficult to detect during routine colonoscopic examination, colonoscopists should make every effort to discover flat adenomas, which seem to play an important role in the adenoma-carcinoma sequence.

Adenoma↗
PubMed1990

Evaluation of inter- and intramolecular primary structure homologies of interferons by a Monte Carlo method.

Using Sellers TT algorithm, primary structure repeats have been described for interferon (IFN)-alpha, -beta 1, and gamma. To reevaluate these results and to extend them to IFN-beta 2 (interleukin-6), a modified algorithm was developed that uses a metric to define the "best" partial homology of two peptide sequences and to compare it to those detected in random permutations of the peptide. Using this approach, the known structural homologies of IFN-alpha with IFN-beta 1 and of human (Hu) IFN-gamma with murine (Mu) IFN-gamma were identified correctly. However, the primary structure repeats in the amino acid sequences of IFN-alpha, -beta 1, and -gamma turned out to be no better than those detectable in random permutations of these sequences. These results were confirmed using a different, nonlinear metric. A previously used approach to demonstrate significance was shown to produce false-positive results. No significant primary structure homologies were detected among IFN-beta 1, -beta 2, and -gamma. In contrast to the amino acid sequence analysis, the DNA sequence of HuIFN-beta 1 contained a significant repeat that had no significant counterpart in MuIFN-beta or in IFN-alpha. In conclusion, some previously reported results obtained with Sellers TT algorithm on amino acid sequences are easily explained as random similarities, and it is therefore strongly recommended that a method like ours should be used to control significance.

Algorithms↗
PubMed1990

Postoperative apnea in former preterm infants: prospective comparison of spinal and general anesthesia.

Thirty-six former preterm infants undergoing inguinal hernia repair were studied. All were less than or equal to 51 weeks postconceptual age at the time of operation. Patients were randomly assigned to receive general or spinal anesthesia. Group 1 patients received general inhalational anesthesia with neuromuscular blockade. Group 2 patients received spinal anesthesia using 1% tetracaine 0.4-0.6 mg/kg in conjunction with an equal volume of 10% dextrose and 0.02 ml epinephrine 1:1000. In the first part of the study, infants randomized to receive spinal anesthesia also received sedation with im ketamine 1-2 mg/kg prior to placement of the spinal anesthetic (group 2 A). The remainder of group 2 patients did not receive sedation (group 2 B). Respiratory pattern and heart rate were monitored using an impedance pneumograph for at least 12 h postoperatively. Tracings were analyzed for evidence of apnea, periodic breathing and/or bradycardia by a pulmonologist unaware of the anesthetic technique utilized. None of the patients who received spinal anesthesia without ketamine sedation developed postoperative bradycardia, prolonged apnea, or periodic breathing. Eight of nine infants (89%) who received spinal anesthesia and adjunct intraoperative sedation with ketamine developed prolonged apnea with bradycardia. Two of the eight infants had no prior history of apnea. Five of the 16 patients (31%) who received general anesthesia developed prolonged apnea with bradycardia. Two of these five infants had no prior history of apnea. When infants with no prior history of apnea were analyzed separately, there was no statistically significant increased incidence of apnea in children receiving general versus spinal anesthesia with or without ketamine sedation. Because of the small numbers of patients studied, and the multiple factors that may influence the incidence of postoperative apnea (e.g., prior history of neonatal apnea), standard postoperative respiratory monitoring of these high-risk infants is still recommended following all anesthetic techniques.

Anesthesia, General↗
PubMed1990

Prospective study of subglottic stenosis in intubated neonates.

Although numerous retrospective studies have attempted to investigate the incidence, etiology, and pathogenesis of subglottic stenosis, there have been few prospective studies. The retrospective studies focused initially on diagnosed cases, then drew inferences regarding incidence and causality based upon data obtained from review of patient records. In contrast, this prospective study accrued data on all neonates intubated for 48 hours or longer during the 1-year intake period. There were 195 neonates entered in the study; then 36 were excluded, leaving 159 for data analysis. Parameters assessed included age at intubation (mean, 5.7 days), duration of intubation (mean, 12.3 days), and number of times reintubated (mean, 0.79). Results of this prospective study are compared to results from previous retrospective studies.

Causality↗
PubMed1989

Issues and problems in measuring children's health status in community health research.

The measurement of children's health status in community surveys is hampered by both methodologic and substantive problems. These include relatively low prevalence of medical conditions among children, appropriate selection of sample questionnaire items, and difficulties in measuring health status change. There is potential value in including measures of health risk instead of, or in addition to, health status measures. This may overcome problems of low prevalence, and provide a broader base for testing the effects of program and policy changes.

Child↗
PubMed1989

High-dose caffeine suppresses postoperative apnea in former preterm infants.

Thirty-two former preterm infants (less than or equal to 44 weeks postconceptual age) undergoing inguinal hernia repair were prospectively studied. General inhalational anesthesia with neuromuscular blockade was used. No barbiturates or opioids were given. Infants were randomly divided into two groups. Group 1 received iv caffeine 10 mg/kg immediately after induction of anesthesia. Group 2 received iv saline. Respiratory pattern, heart rate, and SpO2 were monitored using an impedance pneumograph and a pulse oximeter, respectively, for at least 12 h postoperatively. Tracings were analyzed for evidence of apnea, periodic breathing, and/or bradycardia by a pulmonologist unaware of the drug given. None of the patients who received caffeine developed postoperative bradycardia, prolonged apnea, or periodic breathing, and none had postoperative SpO2 less than 90%. In the control group 13 (81%) developed prolonged apnea 4-6 h postoperatively. Fifty percent of the patients had SpO2 less than 90% at the time. This study shows that iv caffeine 10 mg/kg is effective in the control of apnea in otherwise healthy expremature infants between 37 and 44 weeks of postconceptual age. It is still recommended, however, that all infants at risk be monitored for at least 12 h for apnea and bradycardia following general anesthesia.

Anesthesia, General↗
PubMed1989

Absence of circulating products of oxygen derived free radicals in acute severe asthma.

Oxygen derived free radicals (ODFRs), generated by eosinophils, neutrophils, alveolar macrophages and mast cells, have been proposed as important mediators of inflammatory damage in asthma. We attempted to assess the role of these free radicals in patients with acute asthma by determining serum concentrations of phospholipid-esterified 9, 11 and the parent 9, 12-linoleic acid isomers (9, 11-LA, 9, 12-LA), using HPLC and diode array detection. The diene conjugate, 9, 11-LA, has been shown to be a sensitive and specific marker of free radical activity in other inflammatory conditions. Eight patients (6 female, aged 19-42 years) with acute asthma (mean peak expiratory flow 92 +/- (26) m (SEM) l.min-1, mean PaO2 8.4 (1.0) kPa were studied at 0, 6, 12, 24 and 48 hours after admission to hospital and again 4-6 weeks later. Initial blood samples were taken prior to the administration of oxygen or drug therapy. On admission, mean concentrations of 9, 11-LA and 9, 12-LA were normal at 18.0 (2.8) and 1024 (118) mumol.l-1. All subsequent 9, 11-LA serum concentrations were likewise in the normal range. The serum 9, 11-LA/9, 12-LA ratio was 1.9 (0.4) on admission and 1.6 (0.2) in convalescence (Normal Range 1.0-3.8). These findings in peripheral blood do not support a major role or oxygen derived free radical production in acute asthma, but local airway production cannot be excluded.

Adult↗
PubMed1989

Cystic fibrosis in blacks in Washington, DC: fifteen years' experience.

Controversies exist regarding the clinical presentation and characteristics of cystic fibrosis (CF) in American blacks. Between 1971 and 1986, 188 patients with CF (165 whites, 20 blacks, and 3 others) seen at Children's Hospital National Medical Center, Washington, DC, were evaluated for age at diagnosis, duration of symptoms prior to diagnosis, clinical presentations, initial sputum culture results, and weight and height at diagnosis. Comparisons between black and white patients revealed no statistically significant differences in average age at diagnosis, average duration of symptoms prior to diagnosis, average sweat electrolyte concentrations, or sputum culture results. A breakdown of presenting symptoms by race showed some points of disparity. About twice as many black patients as white patients (40% v 22%) presented with only pulmonary symptoms, whereas slightly more whites presented with only gastrointestinal symptoms (46% v 35%). Those patients presenting with a combination of symptomatology were equally distributed by race (25% black, 21% white). At diagnosis, age-adjusted weight percentiles were significantly lower for black patients than for white patients (chi 2 = 9.60, P less than or equal to 0.05). Although the authors agree that CF is relatively rare among blacks, a high index of suspicion is essential for early diagnosis.

Black People↗
PubMed1988

Bombesin and its analogues inhibit interleukin-2-induced proliferation of CTLL-2 cells.

Specifically interleukin-2 (IL-2)-dependent CTLL-2 cells were incubated in short term culture in the presence of IL-2 together with bombesin and two analogues, [Lys3]bombesin and [Tyr4]bombesin in different concentrations. Cell proliferation, determined by [3H]thymidine incorporation was significantly inhibited by 35.6 +/- 5%, 39.0 +/- 5.6% and 57.0 +/- 11% (mean +/- S.E.M. of 3 independent experiments). A typically U-shaped dose-response relationship was observed, showing a maximum effect between 10(-12) and 10(-10) M. Our data support the hypothesis that this effect is mediated by a specific receptor for bombesin and closely related peptides on CTLL-2 cells. As IL-2 plays a critical role in the clonal expansion of activated lymphocytes, antagonism of the effect of IL-2 is of high biological significance.

Animals↗
PubMed1988

Biological safety cabinets, decontamination or sterilization with paraformaldehyde.

Bacillus subtilis var. niger spores were used to determine the exposure time for formaldehyde decontamination of biological safety cabinets. Formaldehyde contact times less than 3 hr were insufficient for sterilization. A contact time of 4 hr or more resulted in a reproducible killing of the spore strips placed inside the cabinets. At 6 hr sufficient formaldehyde had diffused through the high efficiency particulate air (HEPA) filter to sterilize the strips with lower spore counts. A minimum of 5 to 6 logs of killing were observed after 4 to 6 hr of treatment.

Bacillus subtilis↗
PubMed1987

[Interleukin 2].

Explore the source record for details and available documents.

Cell Line↗
PubMed1987

Substance P enhances interferon-gamma production by human peripheral blood mononuclear cells.

Substance P (SP), a neuropeptide widely distributed in the organism, has been shown to stimulate lymphocyte proliferation and immunoglobulin synthesis. However, the effect of SP on specific lymphokines is unknown. Therefore we investigated the influence of SP on mitogen-induced interferon-gamma (IFN-gamma) production in vitro. Peripheral blood mononuclear cells (PBMC) of healthy donors were isolated by density gradient centrifugation and cultured in supplemented RPMI 1640 medium with phytohemagglutinin (PHA) or pokeweed mitogen (PWM), 0.125 and 0.25 mg/liter each, and varying concentrations of SP (10(-12) to 10(-6) M). After 24 and 48 h, IFN-gamma was measured in the supernatant using radioimmunoassay. Results were expressed as percent change of controls. SP alone had no relevant IFN-gamma inducing properties. It enhanced the IFN-gamma production of PWM-stimulated cells significantly up to 18%. The maximal effect was observed at 10(-8) M. PHA-stimulated cells also increased their IFN-gamma production after addition of SP. However, due to great interindividual variations this effect did not attain statistical significance. Stimulation of IFN-gamma production by SP might be of physiological importance, since the effect was seen at concentrations comparable to those found in the body. Our data lend further support to the immunoregulatory functions of SP.

Cells, Cultured↗