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R A Feldman

Publications and source records attributed to R A Feldman.

At least 91 records · Page 5Linked to original sources
PubMed1982

Salmonellosis associated with marijuana: a multistate outbreak traced by plasmid fingerprinting.

In January and February of 1981, 85 cases of enteritis caused by Salmonella muenchen were reported from Ohio, Michigan, Georgia, and Alabama. Initial investigation failed to implicate a food source as a common vehicle, but in Michigan 76 per cent of the patients, in contrast to 21 per cent of the control subjects, admitted personal or household exposure to marijuana (P less than 0.001, relative risk = 20). Marijuana samples obtained from patients' households contained as many as 10(7) S. muenchen per gram. The outbreak-related isolates of S. muenchen were sensitive to all antibiotics and were phenotypically indistinguishable from other S. muenchen. Plasmid fingerprinting, however, revealed that all isolates related to marijuana exposure contained two low-molecular-weight plasmids (3.1 and 7.4 megadaltons), which were absent in control strains. Plasmid analysis of the isolates showed that the outbreaks in Ohio, Michigan, Georgia, and Alabama were related, and analysis of isolates submitted from various other states demonstrated that cases associated with marijuana may have been dispersed as far as California and Massachusetts.

Adult↗
PubMed1982

Age at onset of necrotizing enterocolitis. Risk factors in small infants.

We compared the features of 45 infants with early-onset necrotizing enterocolitis (NEC) (in the first ten days of life) and 41 infants with late-onset NEC (after the tenth day of life); all weighed 1,500 g or less at birth. Infants with late-onset NEC were smaller at birth and had younger gestational ages than infants with early-onset illness. No significant differences between the two groups, however, were found in sex or race distribution, mean one- and five-minute Apgar scores, or in the relative frequency of occurrence of 30 maternal and neonatal risk factors. Intravenous alimentation was administered significantly more frequently to infants with late-onset NEC. Birth weight-specific weekly attack rates for NEC declined dramatically when infants reached the equivalent of 35 to 36 weeks' gestational age. We hypothesize that the timing of noxious events in relation to gut maturity may explain these observations.

Age Factors↗
PubMed1982

Human Yersinia enterocolitica infections in Wisconsin. Clinical, laboratory and epidemiologic features.

Yersinia enterocolitica has been sought in stool and blood culture specimens by the Wisconsin State Laboratory of Hygiene (SLH) since 1973. Clinical information on symptoms, duration of illness, and use of antibiotics for 41 persons with Y. enterocolitica infections from January 1, 1979, to September 30, 1980, was obtained by telephone interviews. Diarrhea and abdominal pain were the most common symptoms of the ill persons; extraintestinal symptoms were infrequently reported. Ten infected persons (24 percent) had no illness. Review of a 10 percent sample of all stool specimens cultured at the SLH from June 20, 1977, to June 20, 1979, revealed that Salmonella was the most commonly isolated enteric pathogen (15.4 percent) followed by Shigella (2.0 percent) and Y. enterocolitica (0.7 percent). Several different biotypes and serotypes of Y. enterocolitica were associated with illness. Y. enterocolitica isolates were uniformly susceptible to a wide variety of antibiotics, and most isolates were resistant to ampicillin. Epidemiologic studies showed that persons with Y. enterocolitica infections were more likely to live in rural counties than were all persons sending stool samples or those having Salmonella infections; underlying illness was identified as a risk factor for infection.

Adolescent↗
PubMed1982

Epidemiology of diarrhea due to rotavirus on an Indian reservation: risk factors in the home environment.

Analysis of outpatient visits for diarrheal disease at the San Carlos Apache Reservation, Arizona, during 1977-1979 revealed a sharp increase in cases of infantile gastroenteritis of unknown etiology in October and November of each year. During the 1980 autumn diarrhea season, 19 patients and 12 control subjects were selected from among outpatients under two years of age and were interviewed and studied for bacterial and viral enteric pathogens. Eleven (58%) of 19 patients and two (17%) of 12 control subjects were positive for fecal rotavirus by enzyme-linked immunosorbent assay (P = 0.03). Ten (91%) of 11 rotavirus-positive patients were under one year of age. The most significant risk factor for illness was the presence of a household contact under the age of two years (P - 0.004). Dog ownership was also associated with rotavirus infection (P = 0.05).

Adolescent↗
PubMed1982

Salmonella dublin infections in the United States, 1979-1980.

Human isolates of Salmonella dublin were reported to the Centers for Disease Control, Atlanta, 103 times in 1980, as isolation rate nearly twice that reported in 1979. In 1979 and 1980 S. dublin was isolated predominantly in the western United States, frequently from males (60% of the total), from adults older than 40 years of age (55%), and from blood (37%). Detailed histories were obtained for 39 cases outside of California and Oregon, and 32 cases were matched with 62 age-, sex-, and locality-matched control subjects. We found that persons infected with S. dublin were more likely to have suffered from chronic noninfectious diseases (P less than 0.001) and were more likely to have ingested antacids (P less than 0.01) than their controls. In the case-control study, 21 (66%) of the infected persons were hospitalized and six (19%) died. When exposure to cattle, beef, or dairy products was examined, we found that cases differed significantly from controls only by a more frequent consumption of raw milk (P less than 0.001).

Adolescent↗
PubMed1982

Avian sarcoma virus UR2 encodes a transforming protein which is associated with a unique protein kinase activity.

UR2 is a newly characterized avian sarcoma virus whose genome contains a unique sequence that is not related to the sequences of other avian sarcoma virus transforming genes thus far identified. This unique sequence, termed ros, is fused to part of the viral gag gene. The product of the fused gag-ros gene of UR2 is a protein of 68,000 daltons (P68) immunoprecipitable by antiserum against viral gag proteins. In vitro translation of viral RNA and in vivo pulse-chase experiments showed that P68 is not synthesized as a large precursor and that it is the only protein product encoded in the UR2 genome, suggesting that it is involved in cell transformation by UR2. In vivo, P68 was phosphorylated at both serine and tyrosine residues. Immunoprecipitates of P68 with anti-gag antisera had a cyclic nucleotide-independent protein kinase activity that phosphorylated P68, rabbit immunoglobulin G in the immune complex, and alpha-casein. The phosphorylation by P68 was specific to tyrosine of the substrate proteins. P68 was phosphorylated in vitro at only one tyrosine site, and the tryptic phosphopeptide of in vitro-labeled P68 was different from those of Fujinami sarcoma virus P140 and avian sarcoma virus Y73-P90. A comparison of the protein kinases encoded by UR2, Rous sarcoma virus, Fujinami sarcoma virus, and avian sarcoma virus Y73 revealed that UR2-P68 protein kinase is distinct from the protein kinases encoded by those viruses by several criteria. Our results suggest that several different protein kinases encoded by viral transforming genes have the same functional specificity and cause essentially the same cellular alterations.

Alpharetrovirus↗
PubMed1982

DNA sequence of the viral and cellular src gene of chickens. 1. Complete nucleotide sequence of an EcoRI fragment of recovered avian sarcoma virus which codes for gp37 and pp60src.

Recovered avian sarcoma virus is a class of virus obtained from chicken tumors induced by mutants of Rous sarcoma virus which have a deletion in the src gene. We have determined the entire nucleotide sequence of a 3.1-kilobase EcoRI DNA fragment of molecularly cloned recovered avian sarcoma virus DNA. This DNA fragment contains part of the env gene and the entire src gene. Amino acid sequences of both gene products were deduced from the DNA sequences; the predicted amino acid sequences were verified by protein studies. An env protein (gp37) was found to be composed of 205 amino acids with three glycosylation sites. gp37 had a long stretch of hydrophobic residues near the carboxyl terminus. The src gene product, pp60src, was composed of 526 amino acids and contained the possible sites for tyrosine and serine phosphorylation. The amino acid sequences predicted in this study differ significantly from the amino acid sequence predicted previously for the Schmidt-Ruppin strain of Rous sarcoma virus.

Amino Acid Sequence↗
PubMed1982

Age at onset of necrotizing enterocolitis: an epidemiologic analysis.

We studied the epidemiologic interrelationships among birth weight, gestational age, and age at onset of necrotizing enterocolitis of the newborn. As birth weight increased, the range of ages at onset and the mean age at onset both decreased. Weekly birth weight-specific attack rates for necrotizing enterocolitis declined sharply in all birth weight groups when the equivalent of 35-36 wk gestational age was reached. Our data are consistent with the hypothesis that the risk period for necrotizing enterocolitis is determined primarily by the maturity of the gastrointestinal tract of the newborn.

Age Factors↗
PubMed1982

Gastrointestinal illness on passenger cruise ships, 1975-1978.

Following investigations in 1972-1973 of outbreaks of enteric disease on cruise ships using American ports, a surveillance system was established which required that 24 hours before arrival in port, each ship report the number of persons with diarrheal illness seen by the ship's physician during the cruise. The reported data were found to be reliable; they established a baseline incidence for diarrhea on cruise ships. A significantly high portion of enteric disease outbreaks occurred on vessels that did not pass routine annual or semiannual sanitation inspections. The cruise ship sanitation program, developed with the cooperation of the cruise ship industry and the Centers for Disease Control, appears to have been successful in reducing the overall rate of cruise ship associated outbreaks of enteric illness.

Diarrhea↗
PubMed1982

Campylobacter enteritis associated with contaminated water.

Approximately 3000 people in Bennington, Vermont, 19% of the population, had a diarrheal illness during the first and second weeks of June 1978. Persons affected reported abdominal cramps (86%), diarrhea (82%), malaise (73%), and headache (47%). The mean duration of illness was 4.6 days. The illness was associated with drinking unboiled water from the town water system. Investigation showed that the entire water system was probably contaminated and the source of contamination was the main unfiltered water source. Bolles Brook. Campylobacter fetus subspecies jejuni was cultured from 15 of 42 rectal swabs obtained from persons who had been ill, but not from swabs obtained from 23 persons who served as controls. No environmental samples of water and no specimens from wild or domestic animals were positive for Campylobacter. This appears to be the first waterborne outbreak of gastroenteritis associated with C. fetus subspecies jejuni.

Adult↗
PubMed1982

Salmonellosis in infants: the importance of intrafamilial transmission.

In a retrospective review of Wisconsin Salmonella surveillance data, we found that 73 (39%) of 187 families with infant index patients has at least one family members with prior diarrheal illness, compared with only 20 (13%) of 158 families with 5- to 9-year-old index patients (P less than .0001). Prior diarrheal illness was also more commonly identified in families with an infant index patient 0 to 2 months of age (28 of 52 families) than in families with an index patient 3 to 11 months (45 of 135 families) (P less than .02); this difference was found largely in families of infant index patients with siblings. Intrafamilial transmission of Salmonella may explain a large proportion of cases of infant salmonellosis. Older children and adults with salmonellosis may be the most important exposures for infants 0 to 2 months of age.

Child↗
PubMed1981

Sudden death associated with very low calorie weight reduction regimens.

We studied the cases of 17 individuals who died suddenly of ventricular arrhythmia after prolonged use (median 5 months) of very low calorie weight reduction regimens consisting entirely or largely of protein. The deaths appeared to be independent of type of medical supervision received during the diet, daily dosage of potassium supplementation, and biological quality of the protein product used. Factors common to all cases were marked obesity at the onset of dieting, prolonged use of extremely low calorie diets (approximately 300 to 400 kcal daily), and significant and rapid weight loss. Our review of available electrocardiograms and pathological specimens revealed a pattern of cardiac changes previously described in starvation. We conclude that use of very low calorie weight reduction regimens should be curtailed until further studies determine what modifications, if any, can insure their safety.

Adult↗
PubMed1981

An outbreak of salmonellosis involving multiple vehicles.

A biphasic outbreaks of salmonellosis affected customers and employees of a restaurant in Maine, in October and November, 1979. Salmonella typhimurium was isolated from 27 customers and nine employees. Ten other individuals were ill but did not have specimens taken for culture, and there were four secondary cases including one affecting a laboratory technician. Fourteen individuals (28%) were hospitalized for up to 45 days, and a total of 416 days of work were lost as a result of the outbreak. Two different food items served at the restaurant at separate times were identified as vehicles. In the first part of the outbreak, 37 persons who consumed either egg-based foods (p = 0.003) or salad (p = 0.006) became ill. In the second phase of the outbreak, in late October and November, nine cases were associated with consumption of inadequately refrigerated salad (p = 0.008), but not with egg-based foods. An infected symptomatic food handler prepared the incriminated salad for some members of this latter group. Use of antacids was also associated with illness (p = 0.03). The occurrence of illness over a seven-week period, the implication of several vehicles, and the demonstration of secondary cases suggest that "sporadic" cases of salmonellosis in the community may be linked.

Adolescent↗