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L C Alpert

Publications and source records attributed to L C Alpert.

27 records · Page 2Linked to original sources
PubMed1988

Epidemiology of Campylobacter pylori infection: ethnic considerations.

A proper perspective of the association of Campylobacter pylori with various diseases can be achieved only when the incidence of C. pylori infection in the normal population is known. We used the 13C urea breath test (a simple, specific, noninvasive, safe, and reproducible method to assess the presence of active C. pylori infection) to compare the frequency of C. pylori infection in healthy young adults from three areas of the world. We studied 26 women and 32 men (ages 20 to 29): 29 from the United States, 10 from China, 6 from Mexico, and 13 from India. All foreign nationals had been in the United States 5 years or less. The frequency of C. pylori infection was 21%, 67%, 33% and 46%, for those from the U.S., China, Mexico and India, respectively. Although, we found no difference in the frequency of C. pylori infection among ethnic groups from North America (U.S. citizens compared with citizens of Mexico), all individuals studied were of middle to upper class socioeconomic status. Subsequent studies will investigate whether the prevalence of C. pylori infection is different in economically disadvantaged populations. Our results suggest that there may be major differences in the age-related frequency of C. pylori infection in individuals from different parts of the world.

Adult↗
PubMed1988

Iatrogenic Campylobacter pylori infection is a cause of epidemic achlorhydria.

On a number of occasions, there have been descriptions of epidemic achlorhydria in subjects undergoing repeated gastric secretory studies, typically as part of research protocols. We observed a case in a 37-yr-old healthy man undergoing weekly gastric analyses, along with endoscopy and gastric biopsy, as part of a research protocol studying gastric adaptation to aspirin. In the middle of the 2nd wk of aspirin administration, he developed severe nausea and epigastric discomfort. Aspirin administration was discontinued, but, as per protocol, gastric analyses, endoscopies, and biopsies were continued. Compared to the week preceding the acute illness, biochemical analyses showed a transient 7.4-fold increase in basal gastric acid, 3.6-fold increase in pepsin secretion, 8.8-fold increase in DNA loss, 5.6-fold increase in mucus secretion, and 12-fold increase in gastric bleeding. Basal acid secretion was zero, and pepsin secretion was one-third of control during the 2nd wk of the infection. Endoscopy at the time of symptoms showed erosions in the gastric body and antrum, as well as numerous mucosal hemorrhages and an acute ulcer in the antrum. Endoscopy 7 days later revealed that the gastric mucosa had almost completely recovered, with only a shallow erosion seen at the site of the previous ulcer. Gastric biopsies were normal before and during the first 2 wk of aspirin ingestion. Gastric biopsies taken at the time of the acute illness (associated with increased basal acid secretion) showed marked acute inflammation of the antrum with many Campylobacter pylori bacilli. At that time, neither acute inflammation nor C. pylori were found in biopsies from the body of the stomach. Biopsies obtained 1 wk later (zero basal acid) showed acute inflammation of both the gastric body and antrum. One week later, biopsies from the gastric body showed mild focal acute inflammation, moderate chronic inflammation, and an occasional lymphoid follicle; the gastric antrum showed chronic inflammation. Antral biopsies obtained 2 yr later showed persistent chronic gastritis with prominent lymphoid follicles and scattered foci of acute inflammatory cells; C. pylori bacilli were still present, but were less apparent. We believe that the syndrome of acute (epidemic) gastritis is often iatrogenic C. pylori infection. Our case shows that increased basal acid and pepsin secretion occur before onset of basal acid hypochlorhydria in the acute phase of C. pylori infection.

Achlorhydria↗
PubMed1987

Campylobacter pylori detected noninvasively by the 13C-urea breath test.

The high endogenous urease activity of Campylobacter pylori was exploited in a non-invasive test for the presence of this organism in the stomach. When 13C-urea was administered orally after a test meal, urea-derived 13CO2 appeared in the respiratory CO2 of infected individuals at a constant rate for greater than 100 min. The test was validated in 26 individuals who underwent both the 13C-urea breath test and endoscopic biopsy of the antral mucosa for culture and histological examination. Each positive breath test proved to be correlated with a positive culture or Warthin-Starry silver stain of a mucosal biopsy specimen, or both.

Adult↗
PubMed1981

Effect of the growth hormone-secreting tumor StW5 on pituitary and adrenal gland function in rats.

A growth hormone-secreting tumor (StW5 was implanted into male rats and resulted in a tripling of adrenal weight concomitant with a 30% decrement in pituitary weight. Plasma concentrations of corticosterone in tumor-bearing (TB) rats were significantly elevated at rest or after ACTH injections or the stress of either anesthesia. The rise in plasma concentrations of corticosterone was due mainly to the large increment in adrenal size although a significant increase in adrenal responsiveness to ACTH was demonstrated in vitro. In addition, plasma corticosterone concentrations were higher in TB rats despite both a doubling of the blood volume and a 50% increase in liver capacity to metabolize corticosterone. Pituitary ACTH content was significantly lower in TB rats, but these pituitary glands could still release near-normal quantities of ACTH as shown both by in vitro incubations and adrenal corticosterone output following ether stress.

Adrenal Cortex↗
PubMed1976

Localization of LHRH in neurons in frog brain (Rana pipiens and Rana catesbeiana).

Hypothalamic extracts from frogs (Rana pipiens) were found to contain a significant quantity of immunoreactive LHRH (3.27 +/- 0.63 ng/hypothalamus) (mean +/- SE) measured by radioimmunoassay. In additional radioimmunoassay studies of gross brain LHRH distribution in R. pipiens and R. catesbeiana, 16% of the total frog brain LHRH was located within the telencephalon-septum-optic chiasm regions while the remainder was distributed within the infundibular hypothalamic-pituitary complex. Immunohistochemical studies using the peroxidase-anti-peroxidase (PAP) unlabeled antibody enzyme technique demonstrated the presence of LHRH selectively within some neuronal perikarya located primarily in the median septal nucleus. Fibers containing immunoreactive LHRH were seen in the vicinity of these neuronal cell bodies and in the medial and lateral septal nuclei. In addition, LHRH-containing fibers extended to the median eminence and posterior pituitary, transversing a course beneath the preoptic recess or through the medial forebrain bundle, and then through the lateral infundibular hypothalamus to enter the median eminence bilaterally. LHRH within the median eminence was located in both the inner subependymal and outer glandular zones. On the basis of earlier physiological studies, it is proposed that this LHRH-peptidergic septo-infundibular pathway is involved in control of cyclic gonadotropin activity in the frog.

Animals↗
PubMedDate not supplied

Pulmonary paragonimiasis. Report of a case with diagnosis by fine needle aspiration cytology.

We report a case of paragonimiasis in a Nigerian woman evaluated for symptoms of chronic respiratory disease five years after chemotherapy for primary lymphoma of the breast. Fine needle aspiration of one of two fibrocavitary pulmonary lesions yielded thick, brown material in which ova diagnostic of Paragonimus westermani were identified cytologically. This disease is unusual in natives of North America but is seen in travelers and immigrants from Asia, Africa, and South and Central America, where it is endemic. The infection can be fatal, especially if it involves the central nervous system. The clinical differential is broad, but an accurate diagnosis may be made by fine needle aspiration, thus allowing proper treatment.

Adult↗