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Biomedical subjects

C Cuello

Publications and source records attributed to C Cuello.

At least 55 records · Page 3Linked to original sources
PubMed1985

Calcitonin gene-related peptide and its binding sites in the human central nervous system and pituitary.

Binding sites for synthetic human 125I-labeled calcitonin gene-related peptide (125I-CGRP) have been demonstrated in membranes of the human nervous system. Binding was high in the cerebellar cortex (1.35 +/- 0.27 fmol/mg of tissue; mean +/- SEM), spinal cord (1.06 +/- 0.27 to 1.27 +/- 0.23 fmol/mg), and nucleus dentatus (1.02 +/- 0.15 fmol/mg), intermediate in the inferior colliculus (0.80 +/- 0.14 fmol/mg) and substantia nigra (0.75 +/- 0.14 fmol/mg), low in the neocortex, globus pallidus, nucleus caudatus, hippocampus, amygdala, superior colliculus, thalamus, and hypothalamus (0.15-0.32 fmol/mg), and negligible in spinal and sympathetic ganglia and pituitary (less than 0.04 fmol/mg). Autoradiography showed distinct 125I-CGRP binding over the molecular and Purkinje cell layers of the cerebellar cortex and over the substantia gelatinosa posterior of the spinal cord. The highest levels of CGRP-like components were recognized in the dorsal part of the spinal cord and the pituitary gland. In the ventral part of the spinal cord as well as in the pituitary and thyroid glands, CGRP values were higher when measured by radioreceptorassay as compared to RIA, indicating that at least two CGRP-like components are present. The predominant CGRP-like peak on HPLC had the retention time of synthetic human CGRP. Immunohistochemistry revealed the presence of a dense plexus of CGRP immunoreactive nerve fibers in the dorsal horn of the spinal cord.

Autoradiography↗
PubMed1985

Correlations of values of micronutrients in sera with gastric pathology.

Sera were collected in a high-risk area for stomach cancer in Colombia from 857 residents who had been gastroscoped. The levels of 6 micronutrients (retinol, beta-carotene, ascorbic acid, vitamin E, prealbumin, retinol-binding protein) were measured and the mean values correlated with the presence of gastric pathology thought to represent precursors of stomach cancer. Two micronutrients showed important variations in mean levels by gastric pathology: beta-carotene and vitamin E. Beta-carotene levels were low in patients with dysplasia, but no differences were detected for retinol levels.

Adolescent↗
PubMed1985

Urinary sodium-to-creatinine ratio as an indicator of gastric cancer risk.

The difficulties in the estimation of daily intake of sodium chloride in populations are discussed. Total daily output calculations are hindered by the difficulties investigators encounter in obtaining accurate 24-hour urine collections in field work situations. As an alternative, urinary sodium-to-creatinine ratios were investigated. Such ratios, which do not change significantly with circadian excretion rhythms, are useful indicators of the amount of sodium excreted in the urine. Preliminary observations in Colombian populations at high and low risk of gastric cancer indicated higher sodium excretion in the high-risk group. Loss of sodium by other means, especially perspiration, needs to be estimated in some other way.

Circadian Rhythm↗
PubMed1985

Proliferative and antigenic modifications in human epithelial cells in chronic atrophic gastritis.

For the study of both proliferative and antigenic changes in epithelial cells in a disease predisposing to gastric cancer, endoscopic biopsy specimens were analyzed following removal from individuals with chronic atrophic gastritis (CAG); comparisons were made with specimens from normal gastric mucosa. All subjects were from Nariño, Colombia, the population of which has a high age-adjusted incidence of gastric cancer (150/100,000 population) occurring mainly in gastric antrum. After pulse incubation of biopsy specimens with tritiated thymidine ([3H]dThd), microautoradiographic distributions of [3H]dThd-labeled cells in the epithelial lining of gastric pits were correlated with expression of serologically defined gamma-fetal antigen (FA) as a second marker. Measurements were done both in gastric corpus and in antrum for entire gastric pits and over multiple gastric pit compartments. Total numbers of cells per gastric pit column did not differ between the normal and the CAG specimens either in corpus or in antrum; however, both in corpus and in antrum mean numbers of [3H]dThd-labeled cells per gastric pit column and labeling index were almost twice as large for the CAG population (P less than .006). Labeling index differences also were significant over most gastric pit compartments (P less than .02). In antrum gamma-FA-positive lesions had an expanded proliferative compartment with labeling indices significantly greater than those of antigen-negative lesions (P less than .02). This correlation did not extend to biopsy specimens obtained from corpus of stomach where the frequency of carcinoma is low. Findings indicate a hyperproliferative state in CAG compared to the proliferative state in normal gastric mucosa and, in gastric antrum, a further correlation with expression of gamma-FA in hyperproliferating cells. The two markers can be used to aid definition of the gastric mucosa in a disease associated with the development of gastric cancer and in prophylactic dietary intervention programs.

Antigens, Neoplasm↗
PubMed1984

The impact of vaginal cytology on cervical cancer risks in Cali, Colombia.

The role of vaginal cytology screening in preventing invasive carcinoma of the cervix was investigated in Cali, Colombia. The history of previous participation in screening programs was obtained from 204 patients with invasive carcinoma and from 2 sets of age-matched controls: one from the same health center and one for the same neighborhood of the patient. Our results show that the risk of developing invasive carcinoma is at least 10 times greater in non-screened than in screened women.

Carcinoma↗
PubMed1984

Distribution of neuropeptide immunoreactive nerve terminals within the subnuclei of the nucleus of the tractus solitarius of the rat.

The location of substance P, enkephalin and somatostatin (SRIF), and neurophysin II immunoreactive nerve terminals and preterminal processes in the caudal part of the nucleus of the tractus solitarius (nTS) was examined by the indirect immunofluorescence method for immunocytochemistry combined with cytoarchitectural identification of nuclear subgroups in the same tissue. In 22 Sprague-Dawley rats we examined 14-micrometers-thick serial sections of the dorsal medulla at levels from 1 mm caudal to 2 mm rostral to the obex. These sections were incubated with substance P, enkephalin, somatostatin, and neurophysin II antisera. All four peptides were examined in each case and five typical levels (two caudal and three rostral to the obex) were selected for comparison of terminal distribution between peptides. All sections were photographed under the fluorescence microscope and then counter-stained with cresyl violet. This method of analysis revealed distinct patterns of neuropeptide immunoreactivity in the subnuclei of the nTS that varied according to the level of the section. The nTS is responsible for integrating respiratory, cardiovascular (baroreceptor and cardiac), and gastrointestinal functions. The ventrolateral subnucleus (Vl)nTS, ventral subnucleus (v)nTS, interstitial subnucleus (ni)nTS, and intermediate subnucleus (nI)nTS are the major respiratory subnuclei with vlnTS and vnTS prominently associated with pulmonary afferents, ni associated with laryngeal afferents, and nI with tracheal afferents. The vlnTS, vnTS, and ni showed a moderate density of somatostatin-positive nerve terminals, scattered substance P and enkephalin immunoreactivity, and no neurophysin II-positive terminals. The nI showed moderate density of substance P immunoreactive nerve terminals. The subnuclei of the nTS receiving baroreceptor and chemoreceptor afferents--dorsolateral and dorsal (dl and d) subnuclei of nTS--showed scattered substance P immunoreactive nerve terminals. The commissural nucleus of nTS (ncom), which receives most of the cardiac afferents, showed a moderate density of enkephalin-positive immunoreactive nerve terminals. The medial subnucleus (m)nTS at levels rostral to the obex, the primary site for the termination of gastrointestinal afferents, showed substance P immunoreactivity in moderate amounts and weak immunoreactivity for all the other neuropeptides. An important result of these experiments was the observation that regions of the medulla adjacent to the nTS, i.e., the ventral parasolitarius region (vPSR), dorsal (d)PSR, and the periventricular region (PVR) showed the densest amounts of immunoreactive nerve terminals.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗
PubMed1984

Substance P-immunoreactive sensory nerves in the lower respiratory tract of various mammals including man.

The occurrence and origin of substance P (SP)-immunoreactive (IR) nerves in the lower respiratory tract was studied by means of immunohistochemistry in the guinea-pig, rat, cat and man. In addition, biopsies from human material were also analysed by radioimmunoassay. SP-IR nerves were seen in four principal locations: 1) under or within the lining epithelium, 2) around blood vessels, 3) within the bronchial smooth muscle layer, and 4) around local tracheobronchial ganglion cells. Ligation experiments combined with capsaicin pretreatments indicated that all SP-IR nerves in the respiratory tract are sensory. The trachea seems to be mainly supplied by the vagal nerves, while intrapulmonary bronchi and blood vessels receive SP-IR nerves of both vagal and non-vagal (spinal) origin. SP-IR nerves were also found in the human bronchi with principally similar location as in the guinea-pig. The levels of SP-IR in the trachea and peripheral bronchi of man were about 3-4 pmol/g, which is in the same range as the content of corresponding tissues from the guinea-pig. In conclusion, the present experimental findings of SP-IR nerves in the lower respiratory tract in both experimental animals and man support the functional evidence for the importance of SP in the vagal and non-vagal (spinal) control of bronchial smooth muscle tone and vascular permeability.

Adult↗
PubMed1984

Mutagenic activity of nitrosated foods in an area with a high risk for stomach cancer.

In a search for possible sources of mutagens in human foods, a study was made of six common foods in the diet of a population at high risk for gastric cancer (in Nariño, Colombia). No mutagenic activity was demonstrated in nonnitrosated foods. After nitrosation, only one of the foods, fava beans, demonstrated a mutagenic effect. This effect was direct and concentrated in the germ and pulp of the beans.

Carcinogens↗
PubMed1984

Fetal antigens in the precursor stages of gastric cancer.

Gastric epithelial cells, identified in biopsy specimens from individuals with varying degrees of gastritis and cellular atypia, were classified according to morphology and reactivity with an adult tissue-absorbed rabbit antibody to 2nd trimester human fetal tissue. Sections of stomach from normal individuals and patients with superficial gastritis were generally unreactive with this antibody as determined by immunoperoxidase microscopy. However, a progressive increase in the frequency of antigen-positive gastric epithelial cells was observed during the transition from superficial gastritis to mature metaplasia to dysplasia. Adjunct immunohistologic subclassification of gastric lesions, thus, appears to be possible using a suitably prepared antibody probe. This approach may provide additional parameters necessary for assessment of preneoplastic syndromes and contribute to clinical staging of gastric disease.

Antigens, Surface↗
PubMed1984

Evidence for 5-hydroxytryptamine, substance P, and thyrotropin-releasing hormone in neurons innervating the phrenic motor nucleus.

Retrograde tracing with a fluorescent dye (Fast Blue) combined with immunohistochemistry was used to identify putative neurotransmitter(s) at the phrenic motor nucleus in the cat. Fast Blue was injected bilaterally into the diaphragm of five cats, where each phrenic nerve enters the muscle. Seven days later the animals were perfusion fixed and tissue sections from the fourth, fifth, and sixth cervical spinal cord segments were analyzed using a fluorescence microscope. Retrogradely labeled fluorescent phrenic motor neuron cell bodies appeared in all of the segments but primarily in sections from the fifth segment. The same or adjacent transverse sections were then used for the demonstration of the distribution of the neurotransmitters 5-hydroxytryptamine (5-HT), substance P, and thyrotropin-releasing hormone (TRH) in the area of the phrenic motor nucleus using the indirect immunofluorescence technique. The most conspicuous neurotransmitters found at the phrenic motor nucleus were 5-HT and substance P. We observed dense and diffuse fiber networks throughout the ventral horn which contains the phrenic motor nucleus. These fibers contained varicosities in close proximity to phrenic motor neurons. In addition to 5-HT- and substance P-containing nerve endings, some fibers containing TRH were also found in the area of the phrenic motor nucleus. These results are consistent with earlier physiological data suggesting that 5-HT, substance P, and TRH are important neurotransmitters and/or neuromodulators involved in central control of respiration.

Animals↗
PubMed1983

Trends in cancer incidence in Cali, Colombia.

Trends in cancer incidence from 1962 to 177 provided by the cancer registry of Cali, Colombia, are presented. A decline in rates of cancer of the oral cavity, esophagus, and larynx, has coincided with an increase in the rates of lung cancer in women of all ages and in men over 65 years of age. No such rise in lung cancer has been detected in young males. Colon cancer incidence has increased, and a larger proportion of tumors in later years is concentrated around the sigmoid colon. Cervical cancer incidence has declined, but carcinoma in situ of the cervix is being more frequently diagnosed probably as a consequence of vaginal cytology screening programs. Similarities of these findings with those of Puerto Rico and contrasts with trends in the United States and Europe are discussed.

Adult↗
PubMed1983

Diet and gastric cancer: nutrition survey in a high-risk area.

A nutrition survey was done in four Colombian villages situated in the rural area of Nariño, previously identified as exhibiting different levels of risk for gastric cancer and its precursor lesions. The survey was based on personal visits by trained interviewers to a random sample of families in each village. The major findings of the survey reflected a higher consumption of fava beans in villages with high indices of gastric cancer risk and a higher consumption of fresh fruits and vegetables in villages where such indices were lower. Excessive salt intake and lower potassium intake in villages with a high risk of gastric cancer were suggested, but further work is required to test this preliminary observation. A generally low intake of animal proteins and a high intake of cereals in Nariño did not discriminate between villages at different levels of risk to gastric cancer and its precursors.

Adolescent↗
PubMed1982

Socio-economic class differences in cancer incidence in Cali, Colombia.

Based on census tract information, cancer incidence rates for three socio-economic strata of the city of Cali, Colombia, were calculated. Strong negative associations with socio-economic status were found for cancers of the cervix and stomach. Colon cancer and endocrine-related cancers were positively associated with socio-economic status, while no such association was found for rectal cancer. Contrary to data from developed countries, all smoking-related cancers were positively associated with socio-economic class. The role of socio-economic gradients in developing countries is stressed as a basis for etiological research.

Adolescent↗
PubMed1982

[Gastritis - a risk factor in carcinogenesis; epidemiological and morphological findings (author's transl)].

A comparison was made between 239 gastric biopsies from persons in Columbia, district of Nariño, not suffering from carcinoma of the stomach and an equal number of biopsies from a german control group matched for age and sex. Carcinoma risk in columbian population is about four fold as high as in german people (150 resp. 40/100,000). 46% of the columbian and 23% of the german group had gastritis of the antrum with atrophic changes; its incidence is independent of age. This type of gastritis is characterized by significantly more areas of necrotic epithelial lesions in the glandular neck region, proliferation and dysplasia of neck cells, as well as by intestinal metaplasia. This active and progredient type of gastritis may be perceived as a preliminary stage of the intestinal ("epidemiological") type of gastric carcinoma. This is the predominant type of carcinoma in Germany as well. Prospective studies are necessary to show, if patients with increased risk of stomach carcinoma can be identified by diagnosing this type of gastritis.

Adult↗
PubMed1982

Review of the epidemiology of cervical cancer in the Pacific Basin.

Cervical cancer, despite its declining incidence in the developed countries, is still an important cancer in the less-developed world. The mortality and incidence trends for some of the countries in the Pacific Basin are presented. Among the high-risk communities and populations are Colombia (Cali), New Zealand (Maoris), El Paso, Texas (Latin Americans), California (blacks), Hawaii (Hawaiians), Singapore (Chinese and Indians), Hong Kong, Philippines (Manila), New Caledonia (Melanesians), Alaska (American Indians), Fiji. The major risk factors are summarized, with age at first coitus as the key factor; some doubts are expressed about the validity of multiple sexual partners and circumcision of male partners as risk factors. The likely role of herpesvirus is still being studied, and the possible increase in incidence of cervical cancer among younger women could be attributed to greater sexual promiscuity in that group. Some suggestions for future research are made.

Asia, Southeastern↗
PubMed1981

Nitrite stability and nitrosation potential in human gastric juice.

Human gastric juice samples were investigated from high- and low-risk areas (Colombia and Boston) for factors which influence the stability of nitrite and its potential for nitrosamine formation. The samples from individuals with chronic atrophic gastritis and intestinal metaplasia were not reactive to nitrite and supported a rate of nitrosation largely compatible with the nitrite and thiocyanate concentration. The samples from other individuals contained factors which destroyed nitrite and inhibited nitrosation. There were several samples from both groups which had an elevated rate of nitrosation catalyzed by unknown factors. It is suggested that continued hypochlorhydria might deplete gastric juice of its natural protective factors and lead to an elevated risk of gastric cancer in agreement with our earlier etiological model [1].

Colombia↗