Biomedical subjects

A Haq

Publications and source records attributed to A Haq.

70 records · Page 4Linked to original sources

PubMed1985

Vaccination of rabbits against Entamoeba histolytica with aqueous suspensions of trehalose-dimycolate as the adjuvant.

Rabbits were immunized with soluble Entamoeba histolytica antigen with an aqueous suspension of trehalose-6,6'-dimycolate used as the adjuvant. Induction of protective immunity in the immunized animals was demonstrated by enhanced humoral and cell-mediated immune responses and 100% survival after challenge. Administration of soluble antigen only failed to induce a similar degree of protective immunity. Trehalose-6,6'-dimycolate alone produced only a slight increase in nonspecific resistance.

Adjuvants, Immunologic↗

PubMed1985

Experimental infection of rhesus monkeys with Entamoeba histolytica mimics human infection.

Experimental infection of Entamoeba histolytica was successfully established in rhesus monkeys (Macaca mulatta). Parasites of proven pathogenicity maintained through liver passage in hamsters were used in this study. Laparotomized monkeys were inoculated intracecally/intrahepatically with trophozoites, or by oral administration of cysts (2000 cysts/ml). The cysts were isolated from an infected human stool sample. Formation of typical amebic lesions in the inoculated tissues along with alterations in hematologic indices were studied in the infected monkeys. All the experimentally inoculated monkeys showed leukocytosis and mild neutrophilia, while the hemoglobin content and levels of blood sugar and blood urea remained unaltered during the post-infection period. Specific antiamebic antibodies were readily detectable in post-infected sera.

Amebiasis↗

PubMed1984

Interleukin 1 secretion by human monocytes and macrophages.

Interleukin 1 (IL-1) is generally regarded as a major regulator of T lymphocyte proliferation. Macrophages from animals and cloned tumor cell lines have been shown to produce this monokine in response to a variety of stimuli. The ability of human monocytes and macrophages to generate IL-1 is much less well characterized. We previously demonstrated that human monocytes cultured for 1-6 days transformed to macrophages but retained their capacity to support concanavalin A-driven T cell proliferation. However, cultured macrophage capacity to support antigen-driven T cell proliferation began to decline after 3 days of culture and was markedly deficient by 6 days of culture. To determine if this loss of accessory cell function was due to the inability to secrete IL-1, we measured the monokine produced by normal fresh human monocytes and macrophages cultured in vitro from monocytes. IL-1 was assayed by the mouse thymocyte proliferation method. Fresh monocytes secreted IL-1 readily in response to lipopolysaccaride and latex particles. Macrophages cultured from fresh monocytes, however, lost this ability after greater than or equal to 2 days in culture. Mixing experiments failed to demonstrate an inhibitor present in the macrophage supernatants that would suppress thymocyte proliferation. Stimulated T cells incubated with monocytes and 3-day cultured macrophages failed to prolong or promote IL-1 secretion.

Animals↗

PubMed1984

Increased macrophage migration inhibition factor production in hamsters sensitized by amoebic antigen and glucan.

Well defined cell-mediated immune responses were detectable following experimental immunization of hamsters with Entamoeba histolytica antigen, using glucan as an adjuvant. Peritoneal cells from amoeba antigen-glucan sensitized animals, upon incubation with specific antigen in vitro, were found to release into the supernatant a macrophage migration inhibition factor (MIF). Such supernatant fluids inhibited the migration of macrophages from non-sensitized hamsters. The production of MIF was found to be greatly increased if glucan is added to amoeba antigen when sensitizing animals. The optimal concentration for maximum inhibition was recorded at 10(-8) dilution of the supernatant.

Animals↗

PubMed1984

Continuous monitoring of mixed venous oxygen saturation in hemodynamically unstable patients.

A balloon-tipped catheter has recently become available which, when placed in the pulmonary artery, in addition to enabling the usual measurements of pulmonary arterial pressure, pulmonary capillary wedge pressure, and cardiac output by thermodilution, measures mixed venous oxygen saturation (SvO2) by spectrophotometry. Unlike the measurement of cardiac output by thermodilution, which is done intermittently, the continuous measurement of SvO2 is an effective method of monitoring hemodynamically unstable patients, since changes in cardiac output will immediately become apparent via a corresponding change in SvO2. This is of particular benefit in patients in whom knowledge of the immediate effects of therapy is important. It is also of value in assessing the time of onset of action and duration of action when a cardioactive drug is given to increase cardiac output. We suggest that monitoring SvO2 will provide an earlier indication of the effect of both diagnostic and therapeutic interventions and, therefore, will improve our management in such patients.

Aged↗

PubMed1983

The spectrum of right ventricular involvement in inferior wall myocardial infarction: a clinical, hemodynamic and noninvasive study.

The clinical experience with 37 patients with acute transmural inferior wall myocardial infarction who were assessed for evidence of right ventricular involvement is reported. On the basis of currently accepted hemodynamic criteria, 29 patients (78%) had evidence suggestive of right ventricular infarction. However, only 5 (20%) of 25 patients demonstrated right ventricular uptake of technetium pyrophosphate on scintigraphy. Two-dimensional echocardiography or isotope nuclear angiography, or both, were performed in 32 patients; 20 studies (62%) showed evidence of right ventricular wall motion disturbance or dilation, or both. Twenty-one patients demonstrated a late inspiratory increase in the jugular venous pressure (Kussmaul's sign). The presence of this sign in the clinical setting of inferior wall myocardial infarction was predictive for right ventricular involvement in 81% of the patients in this study. It is suggested that right ventricular involvement in this clinical setting is common and includes not only infarction but also dysfunction without detectable infarction, which is likely on an ischemic basis.

Adult↗

PubMed1982

Vasodilator therapy in refractory congestive heart failure: a comparative analysis of hemodynamic and noninvasive studies.

The response to vasodilator therapy was assessed in 12 patients with chronic severe congestive heart failure refractory to conventional treatment. Cardiac output and intraarterial and pulmonary capillary wedge pressures were recorded continuously to assess the hemodynamic response to the vasodilators used. Control and post-treatment M mode echocardiograms and radionuclide angiograms were obtained to assess the change in left ventricular size and ejection fraction concurrent with the hemodynamic improvement. Despite a 33 percent decrease in pulmonary capillary wedge pressure (p less than 0.001) and a 35 percent increase in cardiac index (p less than 0.001), no significant change occurred in left ventricular end-diastolic or end-systolic chamber size on echocardiography or in ejection fraction measured with radionuclide angiography. In this study M mode echocardiography and radionuclide angiography were of no value in monitoring the actual hemodynamic response to vasodilator therapy in this group of patients with a left ventricular ejection fraction of less than 30 percent.

Aged↗

PubMed1982

Preliminary experience with continuous ambulatory peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) was employed in seven patients of endstage renal failure (ESRF). All the patients had symptom-free ambulant life during CAPD. Blood pressure was well controlled and the haemoglobin level improved significantly. Blood urea and serum creatinine levels were maintained near normal levels. Metabolic acidosis was corrected. Recurrent peritonitis, heavy protein loss and catheter failure were the main complications of CAPD. It appears from these observations that CAPD may be helpful in patients with ESRF.

Abdomen↗

PubMed1981