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Biomedical subjects

C Lopez

Publications and source records attributed to C Lopez.

At least 181 records · Page 10Linked to original sources
PubMed1977

Correlation of clinical and virus-specific immune responses following levamisole therapy of recurrent herpes progenitalis.

Patients with herpes progenitalis recurring every 14--28 days were treated with levamisole 150 mg orally twice weekly in an open trial to evaluate the relationship between immunomodulation and clinical response. Eight of 12 patients studied for 4--9 months reported a decrease in the frequency of recurrences. Enhanced virus-specific lymphoproliferative responses were observed in six of eight patients reporting clinical improvement. Herpes-antigen-induced production of leucocyte migration inhibitory factor (LMIF) was similarly enhanced in these individuals. In the four patients reporting no improvement, virus-specific lymphoproliferative and LMIF-generating responses were either depressed or unchanged. No significant alterations in neutralizing antibody titers were observed in any of the patients. Alterations in virus-specific lymphocyte transformation and lymphokine generation observed in vitro thus correlate with changes in clinical course in a manner consistent with the proposed immunomodulatory function of levamisole.

Herpesviridae Infections↗
PubMed1977

Arabinosyl-N6-hydroxyadenine: a new potent antivirus drug.

Abrabinosyl-N6-hydroxyadenine (ara-HA) was tested for its antiherpesvirus and immunosuppressive activities in vivo and in vitro. Mouse strains were used that had been shown earlier to be very susceptible to intraperitoneal (i.p.) or intracerebral (i.c.) inoculation of a virulent strain of herpes simplex virus Type 1 (HSV-1). Susceptible mice were inoculated i.p. or i.c. with a stock pool of HSV-1 and treated with ara-HA (i.p.) beginning at least 24 hr later. The mice were given a 10-day course of drugs and followed for at least 21 days. Similar experiments were carried out with ara-A for comparative purposes. Ara-HA was found to protect mice inoculated with HSV-1 significantly better than ara-A. Lower concentrations of drugs were required and a higher percentage survived. Later challenge of the ara-HA-treated mice with HSV-1 demonstrated that these mice had become immune to HSV-1, indicating that the immune system is not severely affected by this course of ara-HA. A 10-day course of ara-HA, which was found to protect mice from 100 LD50 of HSV-1, reduced the capacity of the mouse lymphocytes to respond to allogeneic cells only slightly. In vitro ara-HA inhibited HSV-1 replication as well as proliferation of lymphocytes exposed to mitogen.

Animals↗
PubMed1977

The dentition of the Queckchi Indians. Anthropological aspects.

The incidence of nine minor dental traits, in 540 Queckchi Indians from Guatemala is reported. A combination of frequencies of neither Caucasoid nor Mongoloid groups was observed. The apparently Caucasoid elements of their tooth morphology might well be the result of admixture with Spanish genes during the conquest.

Dentition↗
PubMed1977

Influence of the route of administration of prostaglandin E1 on rat gastric secretion.

Changes in gastric secretion induced by the subcutaneous, intraduodenal or intragastric administration of prostaglandin E 1 (PGE1) were evaluated in pylorus-ligated rats. Subcutaneous and intraduodenal injections produced a dose-related inhibition in both total acid and volume of gastric secretion. Dose-response curves for inhibition obtained by these routes were parallel, although PGE1 was more potent when given subcutaneously. Gastric administration produced a dose-related decrease in acid and an increase in volume. The slope of the dose-response curve for acid inhibition with this route was flatter than with subcutaneous or intraduodenal administrations. The present results suggest that PGE1 inhibits gastric secretion by the same mechanism of action when given subcutaneously or into the duodenum, while the effects observed after gastric administration are consequences of local actions. The difference in potency of PGE1 given subcutaneously and in the duodenum would seem to be due to differences in absorption from the site of administration and/or to a greater metabolism of PGE1 during its absorption from the intestines.

Animals↗
PubMed1977

Defective recognitive immunity in family aggregates of colon carcinoma.

Cancer-free individuals from family agregates of seemingly hereditary colon carcinoma were studied to determine the nature of their cell-mediated immune capacities in miexed leukocyte culture. Members of families who demonstrated no evidence of a precancerous condition such as polyposis coli did demonstrate substantial cellular immunopathology. Of these, 44% showed a decreased responsiveness of their peripheral mononuclear cells to allogeneic stimuli, and in a number of these individuals this deficiency clearly manifested itself as an inappropriate suppression of potentially normal lymphocyte blastogenic capacities by an adherent population of mononuclear leukocytes. This in vitro defect of recognitive immunity appears to be the same type of defect that has already been described for individuals with established maligancies. The pattern of phenotypic expression of this immunopathology within these families is not inconsistent with an hereditary disorder. Individuals from families with a known hereditary somatic precancerous condition usually did not demonstrate this immunopathology. It is appropriate to speculate that the defect of recognitive immunity in the former families could be contributory to the genesis of the colon carcinoma.

Adolescent↗
PubMed1977

Cell-mediated immune responses in patients with recurrent Herpes Simplex infections. II. Infection-associated deficiency of lymphokine production in patients with recurrent herpes labialis or herpes progenitalis.

Herpes simplex virus antigen-induced lymphocyte proliferation and production of leukocyte migration inhibitory factor (LMIF) and lymphocyte-derived interferon were studied in normal individuals and patients with recurrent Herpes labialis and Herpes progenitalis. Virus-specific lymphoproliferative responses were regularly detected in patients with recurrent infection irrespective of the clinical stage of infection. In contrast, transient deficiencies in herpes-specific lymphoid production of both LMIF and interferon were regularly documented at the time of and immediately before herpes simplex-induced vesicular eruptions. During the convalescence, pronounced production of these mediators in response to antigenic stimulation with inactivated virus antigen preparations were regularly detected. The biology of these fluctuations in lymphokine production is evaluated and discussed.

Antigens, Viral↗
PubMed1977

Cell-mediated immune responses in recurrent herpesvirus infections. I. Lymphocyte proliferation assay.

Studies in immunosuppressed and immunodeficient patients indicate that the cell-mediated immune response appears to be responsible for controlling reactivated herpesvirus infections. In this study, the various parameters of a herpesvirus (types 1 and 2) antigen specific lymphocyte proliferation assay were optimized and used to evaluate individuals with clinical, recurrent HSV-1 and HSV-2 infections. Normal individuals with neutralizing antibody to HSV-1 or HSV-2 responded to virus antigen in culture as well as individuals with recurrent disease. Normal individuals without neutralizing antibody responded with a significantly lower response. Specificity of the lymphocyte proliferation assay was observed most strikingly in normal individuals with a rare HSV-1 infection during the vesicular eruption. Specificity was also observed by determining the ratio of the response to HSV-1 as compared to the response to HSV-2. Evaluated in this manner, individuals with recurrent HSV-1 infections had significantly higher ratios than individuals with HSV-2 infections and vice versa. Data from individuals with recurrent disease was compared to that of normal individuals to determine whether the former demonstrated a specific alteration in this response. Individuals with recurrent disease were found to have higher neutralizing antibody titers than normals. The neutralizing antibody titers in normal individuals correlated well with the lymphocyte proliferation assay results, whereas a similar evaluation in individuals with recurrent disease gave a negative correlation. The ratio of HSV-1 response/HSV-2 response also demonstrated a suppressed response in recurrent infections to the homologous virus during active disease, which disappeared when the individual was convalescent. These studies indicate that individuals with recurrent HSV infections have virus antigen specific alterations of their cell-mediated immune response, which can be associated with their disease.

Antibody Specificity↗
PubMed1974

Cytomegalovirus: Clinical virological correlations in renal transplant recipients.

One-hundred thirty-two renal transplant recipients were systematically screened for viral infections and the findings correlated with the clinical course. One-hundred ten patients showed evidence of infection with herpesviruses and 89 patients showed laboratory evidence of infection with cytomegalovirus (CMV) uncomplicated by bacterial infections or technical complications. Patients without viral infections were usually asymptomatic. After recovery and development of anti-viral antibodies, most patients were asymptomatic despite the persistence of viral excretion in the urine. In contrast, the onset of viral infections were almost always accompanied by a significant clinical illness characterized by fever, leukopenia, and renal malfunction. Of 89 patients with cytomegalovirus infections, 83 survived at least three months. In these patients, the fever appeared to be self-limited and resolution of the fever was accompanied by increases in anti-CMV antibody. Renal biopsies demonstrated typical rejection reactions in all the biopsied patients and renal malfunction usually responded to anti-rejection treatment. Six of the 89 patients with CMV infections died within a month of viral isolation. These patients could be distinguished from those who recovered by a decreased or absent antibody response to the virus, suppressed lymphocyte responses to mitogen in autochthonous blood, and absent histologic evidence of rejection in the renal allografts. Thus, two paradoxical responses to CMV infections are seen in transplant patients: In the relatively immunocompetent patient, the infection is associated with renal allograft rejection, a prompt antibody response to the virus, and recovery. The severely immunosuppressed patient cannot make an antibody response, does not exhibit allograft rejection as a cause of renal malfunction, he may be further immunosuppressed by the viral infection, and is susceptible to sequential opportunistic infections leading to death.

Biopsy↗
PubMed1973

Isolation of Aleutian mink disease virus by affinity chromatography.

Affinity chromatography was used to isolate the Aleutian disease virus of mink. Dissociation of the immunoadsorbent-virus complex with 0.75 molar sodium chloride and then with a glycine-hydrochloride gradient released infective particles resembling picornaviruses. The elution profile suggests that two different types of virus-antibody complexes are formed, one dissociated by sodium chloride and another that requires glycine-hydrochloride in addition to sodium chloride for release of virus.

Adsorption↗