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Biomedical subjects

H Greenberg

Publications and source records attributed to H Greenberg.

At least 109 records · Page 6Linked to original sources
PubMed1982

Seroepidemiology of heat-labile enterotoxigenic Escherichia coli and Norwalk virus infections in Panamanians, Canal Zone residents, Apache Indians, and United States Peace Corps volunteers.

Serum antibody titrations against the heat-labile enterotoxin (LT) of Escherichia coli were carried out on Panamanians, U.S. citizens resident in the Panama Canal Zone, Apache Indians living on the reservation in Whiteriver, Arizona, and Peace Corps volunteers before they traveled overseas. Antibody titers to Norwalk virus were also carried out on serum from Panamanian and Canal Zone residents. A high prevalence of low-titer LT antibodies was found in infants and adults from Panama, the Canal Zone, and Whiteriver. Panamanian children aged 1 to 5 years had the highest LT antibody titers. Peace Corps volunteers had a low prevalence and titer of LT antibodies. Prevalence and titer of antibodies to Norwalk virus were generally higher in Panamanians compared with Canal Zone residents of the same age. In the populations we studied, various modes of transmission and mechanisms of immunity likely explain the differences which we observed in antibody prevalence and titer to these two enteric pathogens.

Adolescent↗
PubMed1982

Primary carcinoid tumor of the uterine cervix presenting as an adenosquamous carcinoma. The importance of electron microscopy and immunohistochemistry in evaluating poorly differentiated cervical neoplasms.

Primary carcinoid tumors of the uterine cervix are uncommon gynecologic neoplasms. An unusual case of this neoplasm is presented that was originally diagnosed as a poorly differentiated adenosquamous cervical carcinoma. A subsequent metastatic pulmonary nodule was discovered 13 months later with the unexpected histologic and ultrastructural features of a carcinoid tumor. The primary cervical malignancy was reassessed ultrastructurally and the original diagnosis was changed to that of a poorly differentiated carcinoid tumor. By using immunoperoxidase techniques, it was observed that serotonin granules were present in the neoplastic cells of the lung and cervix, confirming the carcinoid nature of the tumor. This case differs from the majority of those reported as poorly differentiated cervical carcinoids in that it did not resemble an undifferentiated small cell (oat cell) carcinoma, but was more typical of an adenosquamous carcinoma. This case supports the role of electron microscopy and immunohistochemistry in the complete evaluation and diagnosis of less-differentiated cervical neoplasms in order to specifically identify the primary cell (cells) of origin. Only in this way can one definitively support the diagnosis of a primary carcinoid tumor and perhaps, with this knowledge, the clinicobiologic behavior of this cancer can be altered and possibly improved by initiating different or adjunctive treatment modalities.

Carcinoembryonic Antigen↗
PubMed1982

Müllerian adenofibroma of the endometrium. A report of a case with ultrastructural study.

A case of müllerian endometrial adenofibroma is presented and the light and ultrastructural features are described. The tumor arose in the lower uterine segment and was composed of a prominent fibroblastic growth of club-shaped papillae projecting into cystic spaces and into the endometrial canal. The lining epithelium was both mucinous endocervical and endometrial in type. A feature not previously described was smooth muscle within the stromal component. The endometrial adenofibroma is a distinct clinicopathologic entity and is part of the family of uterine mixed mesodermal tumors.

Adenofibroma↗
PubMed1981

Lymphocytotoxic and microbial antibodies in Crohn's disease and matched controls.

Patients with Crohn's disease and age, sex and seasonally matched healthy controls were studied for cold lymphocytotoxic and a variety of microbial antibodies. Lymphocytotoxic antibody titers were increased significantly in the Crohn's patients compared to controls, but did not correlate with any of the microbial titers. Antibodies to a Pseudomonas-like bacterium and Bacteroides vulgatus were also increased in the patients, but titers to Chlamydia trachomatis, rotavirus and Norwalk virus were not elevated above control values. Analysis of microbial antibody within the patient and control groups revealed a significant (P = .001) correlation between antibodies to the Pseudomonas-like bacterium and Bacteroides vulgatus. The elevated titers to the Pseudomonas-like organisms and B. vulgatus are of potential importance, but their significance is not known at this time. There is no evidence of an increased incidence of infection with C. trachomatis, rotavirus or Norwalk virus in Crohn's disease.

Adult↗
PubMed1981

Biweekly prophylactic doxycycline for travelers' diarrhea.

A double-blind study to determine the efficacy of biweekly oral doxycycline in the prevention of travelers' diarrhea was conducted among 46 Peace Corps volunteers during their first six weeks in Honduras. The volunteers took either 100 mg of doxycycline per dose or a placebo for three weeks and were observed for an additional three weeks. There was no significant difference in the number of persons with travelers' diarrhea in the two groups (eight of 24 in the doxycycline group and 10 of 22 in the placebo group) in the three weeks when the drug was taken. However, significantly fewer episodes (P less than 0.05) of travelers' diarrhea occurred in the doxycycline group than in the placebo group at the end of the second, third, and fourth weeks. Enterotoxigenic Escherichia coli (ETEC) was the most common pathogen identified. ETEC from 13 (62%) of 21 stool samples were resistant to doxycycline. Biweekly doxycycline was only marginally effective in preventing travelers' diarrhea and did not prevent diarrhea secondary to doxycycline-resistant ETEC.

Adult↗
PubMed1981

A 27-nm virus isolated during an outbreak of acute infectious nonbacterial gastroenteritis in a convalescent hospital: a possible new serotype.

An outbreak of acute infectious nonbacterial gastroenteritis began among elderly patients in a convalescent hospital in Marin County in northern California in March 1978 and persisted through May 1978. The overall clinical attack rate was 51% of 187 residents and 12% of 180 employees. A 27-nm viruslike particle was observed by immune electron microscopy in stools obtained at or near the onset of illness from four of 32 patients. Seroresponses to the 27-nm particles were found by immune electron microscopy in 16 of 18 patients. In addition, serologic evidence of infection with this or a related agent was demonstrated in persons who developed illness in another large outbreak of acute infectious nonbacterial gastroenteritis which occurred in a nearby county. This agent is morphologically similar to but serologically unrelated to the Norwalk and Hawaii gastroenteritis agents and has been designated the Marin agent pending further classification.

Acute Disease↗
PubMed1981

A prospective study of rotavirus infection in infants and young children.

Diarrhea in neonates, followed as a cohort, and their families was studied prospectively. The families were followed for an average of 16.3 months. Stool and serum specimens were obtained at least every three months. Stool specimens were examined for viruses by electron microscopy and cultured for enteropathogens, and serum specimens were tested for antibodies to rotavirus and Norwalk virus. During the study, 237 episodes of gastroenteritis were observed in 104 infants and their 62 siblings. Rotavirus, detected 82 times in 72 children, was by far the most common enteropathogen. It was associated with gastrointestinal symptoms in 72% (with diarrhea in 65%). Rotavirus diarrhea occurred mostly in winter months and was significantly more frequently associated with respiratory symptoms than were diarrheas with other etiologies. Rotavirus infection was uncommon in the first six months of life, but by two years of age, 62% of the infants had had at least one infection. Neither breast feeding nor the presence of antibody to rotavirus in cord blood appeared to be protective.

Antibodies, Viral↗
PubMed1981

Travelers' diarrhea in panamanian tourists in Mexico.

To determine whether residents of developing countries are unlikely to acquire travelers' diarrhea, 64 Panamanians of widely divergent socioeconomic strata were studied during a 15-day tour through Mexico. Twenty-three (36%) tourists experienced 27 episodes of travelers' diarrhea that were caused by seven different pathogens. The most commonly identified etiologic agents were rotavirus (26%), Norwalk virus (15%), and Campylobacter fetus (11%), whereas enterotoxigenic Escherichia coli was not frequently associated with travelers' diarrhea. Acquisition of travelers' diarrhea was correlated directly with high socioeconomic status. Varying levels of immunity to enteropathogens that are endemic in Panama may explain the different isolation rates of pathogens.

Adolescent↗
PubMed1979

Surgical treatment of stages IB and IIA invasive carcinoma of the cervix by radical abdominal hysterectomy.

From 1963 to 1977, 349 radical abdominal hysterectomies with bilateral pelvic lymphadenectomy were performed for Stage IB (331 patients) and Stage IIA (18 patients) cervical cancer at the New York Medical College, with no operative deaths. Definitive diagnosis was obtained from the biopsy specimen in 281 patients. Twenty-nine patients were pregnant when the diagnosis was established. The average operating time was 4 hours and 48 minutes with an average blood loss of 900 ml. Eleven fistulas were noted: ureterovaginal, 7; vesicovaginal, 3; rectovaginal, 1. Since 1972, there have been no fistulas in 130 radical hysterectomies. Metastatic carcinoma of the regional lymph nodes was discovered in 27 patients for an incidence of 7.7%. Postoperative total pelvic external irradiation was utilized in 40 patients (27 with positive nodes, 10 with microscopic carcinoma in vascular channels, and an additional three patients with an inadequate vaginal extirpation margin). A total of 62% of those patients with poor prognostic criteria receiving postoperative irradiation are alive and well. Two hundred nineteen patients have been followed up for at least 5 years and the survival rate was 90%. Our data support the view that radical abdominal hysterectomy with bilateral pelvic lymphadenectomy is the treatment of choice for patients with Stages IB and IIA cervical cancer in the nonpregnant state, unless there are major medical contraindications.

Adenocarcinoma↗
PubMed1977

Unexpectedly high frequency of antibody to Mycoplasma pneumoniae in human sera as measured by sensitive techniques.

Mycoplasmacidal and radioimmunoprecipitating antibodies to Mycoplasma pneumoniae were commonly detected in healthy children younger than five years of age, in whom natural disease due to M. pneumoniae is rare. Antibody in serum could also be demonstrated in Marine recruits several weeks or months before development of pneumonia due to M. pneumoniae. The latter observation suggests that serum antibody does not confer protection against disease caused by M. pneumoniae.

Adolescent↗
PubMed1977

Immunoprophylaxis of experimental Mycoplasma pneumoniae disease: effect of route of administration on the immunogenicity and protective effect of inactivated M. pneumoniae vaccine.

Formalin-inactivated Mycoplasma pneumoniae vaccine was administered subcutaneously or intranasally to hamsters to examine the effect of route of administration on immunogenicity and protective effect. Parenterally administered vaccine in the doses employed induced serum complement-fixing antibody formation, but did not significantly decrease the frequency of pneumonia following challenge with virulent M. pneumoniae. Intranasally instilled vaccine was ineffective in stimulating serum antibody, but did diminish the frequency of experimentally induced pneumonia due to M. pneumoniae. However, a greater degree of resistance was induced by intranasal infection with either wild-type organisms or the ts 640 attenuated mutant of M. pneumoniae.

Administration, Intranasal↗
PubMed1976

The response of canine coronary vascular resistance to local alterations in coronary arterial P CO2.

The effect of hypercapnia on coronary vascular resistance (CVR) was studied in seven open-chest dogs. Coronary blood flow was supplied to the cannulated left main coronary artery from the femoral artery by a precision pump. Coronary arterial PCO2 was locally controlled with a small membrane oxygenator in the coronary perfusion circuit. Each PCO2 change was made at a constant coronary flow, and CVR was calculated from the ratio of perfusion pressure to flow. Coronary sinus (CS) PCO2 and PO2 were recorded continuously from blood withdrawn through a CS catheter. Normocapnia (PCO2 = 42.3 +/- 2.8 mm Hg) was obtained with a membrane oxygenator gas composition of 95% O2-5% CO2, and hypocapnia was produced with 100% O2-0% CO2. In addition to physiology normal coronary flow (determined by a CS PO2 of 20-30 mm Hg) relatively high and low flow states were studied. At a normal control CS PO2, a decrease in coronary arterial PCO2 from 42.3 +/- 2.8 to 23.8 +/- 1.3 mm Hg caused CVR to increase by 84.2%, from 1.27 +/- 0.06 to 2.30 +/- 0.04 units. Since pH was inversely related to PCO2, the effect on CVR may have been mediated through a pH change. CS PCO2 decreased from 65.2 +/- 1.9 to 39.4 +/- 1.3 mm Hg. myocardial oxygen consumption was unchanged. Increases in CVR of 74.5, 119.5, and 69.3% occurred during hypocapnia in three additional experiments in which control arterial PO2 was maintained at 52-90 mm Hg. When CS PO2 was greater than 30 mm Hg, the normocapnic CVR was high, and was only minimally increased by hypocapnia. When coronary flow was reduced to an ischemic level there was little response in CVR to hypocapnia. Thus the level of arterial PCO2 can have an important effect on CVR independent of changes in O2 consumption. Myocardial PCO2, derived from metabolically produced CO2 and contributed to by arterial CO2, may be a major factor in normal control of coronary flow.

Animals↗
PubMed1975

Effects of nitroglycerin on the major determinants of myocardial oxygen consumption. An angiographic and hemodynamic assessment.

A direct and quantitative study of the effects of sublingually administered nitroglycerin on the major determinants of myocardial oxygen consumption was carried out in 10 patients, 7 with coronary artery disease. Left ventricular wall tension, estimates of the contractile state and heart rate were studied directly using simultaneous pressure measurements and angiographically obtained volume determinations. The peak systolic left ventricular wall tension decreased 15 percent after administration of nitroglycerin, suggesting a diminished myocardial oxygen requirement. Increased myocardial oxygen requirements were suggested by the occurrence of both positive chronotropic and inotropic effects. Heart rate increased 15 percent. The mean circumferential fiber shortening velocity increased 26 percent and the ejection fraction 30 percent; these findings, in association with a 23 percent reduction in left ventricular end-diastolic volume, were considered consistent with an increase in the contractile state. The mechanism of action of nitroglycerin seems to relate best to the decrease in systolic wall tension. The end-diastolic tension decreased 57 percent, suggesting the possibility that diastolic coronary blood flow may be augmented by diminished extravascular resistance to flow.

Adult↗
PubMed1975

Experimental studies on human health effects of air pollutants. III. Two-hour exposure to ozone alone and in combination with other pollutant gases.

Adult male volunteers were exposed to ozone (O3) at 0.25, 0.37, or 0.50 ppm, and to O3 in combination with nitrogen dioxide (NO2) and carbon monoxide (CO), with secondary stresses of heat, intermittent light exercise, and repeated exposure. Few important physiological changes, and only mild symptoms, were found with 0.25 ppm O3, with 0.25 ppm 03 plus 0.30 ppm NO2, or when 30 ppm CO was added to the latter mixture. With 0.37 ppm O3, more symptoms were present and some subjects developed definite decreases in pulmonary function. With 0.50 ppm O3, most subjects had symptoms and about half showed substantial pulmonary function decrement. In reactive subjects exposed on two successive days, changes were usually greater the second day, indicating that effects of successive exposures were cumulative.

Adult↗