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A De

Publications and source records attributed to A De.

72 records · Page 4Linked to original sources
PubMed1991

Metacyclogenesis of Leishmania spp: species-specific in vitro transformation, complement resistance, and cell surface carbohydrate and protein profiles.

Metacyclic (stationary) and logarithmic (log) forms of promastigotes of Leishmania donovani and Leishmania major were characterized in several ways. The highly active metacyclic forms were larger with more protein and less carbohydrate. The flagellum increased in length 2.4 times in L. major as compared to 1.8 times in L. donovani. Resistance to complement-mediated lysis by normal human serum of in vitro grown Leishmania promastigotes was related to the species, the growth phase in culture, and also the temperature. Metacyclic forms of both species had a much increased resistance to killing by normal serum at different temperatures. Differences in membrane-exposed carbohydrates were detected by fluorescein-conjugated lectins. Peanut agglutinin and Ulex agglutinin I differentiated log and stationary phase promastigotes of L. major. Higher amounts of acid phosphatase were demonstrated in the metacyclic phase. Differences in polypeptides were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two polypeptides of approximately 51 and 114 kDa were found exclusively in metacyclic promastigotes of both species, whereas 38- and 23-kDa polypeptides were lost or reduced during transformation from log to metacyclic phase promastigotes of L. donovani. In addition, a 75-kDa polypeptide was expressed only in metacyclic promastigotes of L. major.

Acid Phosphatase↗
PubMed1990

Kinetoplastid flagellates: surface-reactive carbohydrates detected by fluorescein-conjugated lectins.

Membrane-associated carbohydrate residues of 3 isolates of Leishmania derived from etiological agents of visceral leishmaniasis (VL), postkala-azar dermal leishmaniasis (PKDL), and cutaneous leishmaniasis (CL), as well as 2 other nonpathogenic insect gut kinetoplastid flagellates, Bodo sp. and Herpetomonas sp., were characterized with the aid of 8 fluorescein-conjugated lectins. Four lectins, concanavalin A, Dolichos biflorus, phytohemagglutinin P, Ricinus communis agglutinin, bound to all kinetoplastid flagellates at different concentrations. All Leishmania promastigotes showed reactions with Ulex agglutinin. Although these lectins were bound to all kinetoplastids, the site and intensity of binding was different. All skin-dwelling Leishmania parasites, viz., Leishmania donovani of PKDL and Leishmania tropica of CL showed unique selectivity toward peanut agglutinin (PNA), soybean agglutinin, and wheatgerm agglutinin (WGA). More interestingly, Herpetomonas showed positive fluorescence with PNA and WGA, whereas Bodo was negative. The results demonstrated that no lectin could distinguish between the pathogenic and nonpathogenic status of kinetoplastid flagellates. Moreover, the antigenic (carbohydrate) profiles of Herpetomonas corresponded more closely to those of L. tropica, whereas Bodo shared some common lectin receptors with L. donovani of VL.

Animals↗
PubMed1988

Factors influencing the cellular response in bronchoalveolar lavage and peripheral blood of patients with pulmonary tuberculosis.

Subsegmental bronchoalveolar lavage was performed in 30 patients with active pulmonary tuberculosis and six control subjects. Total leucocyte count, absolute lymphocyte count, count of polymorphonuclear leucocytes, T and B lymphocytes were determined in peripheral venous blood. These parameters and macrophage counts were also determined in bronchoalveolar lavage fluid. Variations in the cellular responses were correlated with patients' age, sex, nutritional status and duration of symptoms as well as radiological severity of disease. Patients of both sexes (seven female) showed similar responses. Decreased cell counts in peripheral blood were observed in patients aged 31 to 40 years. Well-nourished patients (n = 19) had higher counts of lymphocytes in peripheral blood and polymorphonuclear leucocytes in bronchoalveolar lavage fluid. The duration of symptoms had a significant influence on cellular responses. In blood, lymphocyte counts were increased in those with symptoms of shorter duration but reduced in those symptomatic for more than 6 months. In bronchoalveolar lavage fluid also all cellular elements were increased in those symptomatic for less than 6 months but a decline followed in those with symptoms for longer duration. Patients with minimal disease radiologically showed higher total leucocyte counts in blood, whereas those with moderately advanced lesions had elevated absolute lymphocyte counts. T cell lymphopenia was observed in blood of patients with far advanced disease. The inflammatory response in bronchoalveolar lavage fluid, however, increased in parallel with the severity of disease. Patients with far advanced lesions showed marked inflammation irrespective of duration of symptoms. Thus, the pattern of inflammation in bronchoalveolar lavage fluid was not similar to that in peripheral blood, particularly in patients with far advanced lesions.

Adolescent↗
PubMed1982

Preparation and composition of mouse tubular and glomerular basement membranes.

Methods were developed to obtain tubules and glomeruli and their respective basement membranes from mouse kidneys. While the procedures are especially useful for preparing tubules, one method can be used to simultaneously prepare both tubules and glomeruli. Tubules can be obtained from single animals, while a minimum of five animals are required in order to prepare glomeruli. Either minced whole kidneys or dissected cortex tissue is dispersed using a polytron and the desired fractions are obtained by sucrose density gradient centrifugation. discontinuous gradients consisting of 49.5, 53, 57, and 60% sucrose are used in the first method. Following centrifugation, tubules are collected on the 49.5% sucrose layer and glomeruli are pelleted on the bottom of the tube. In the second method, disrupted tissue is mixed with 57% sucrose and after centrifugation a layer of pure tubules is obtained from the top of the sucrose solution. Basement membranes are then obtained by a sonication method and the average yields per kidney are 0.1 mg and 0.02 mg for tubular and glomerular basement membranes respectively. Their chemical compositions are similar to the respective basement membranes from other species.

Amino Acids↗
PubMed1981

Ergonomics study of tea-leaf plucking operations: Criteria for selection and categorisation.

This paper describes a new method for the categorisation of female tea-leaf pluckers on the basis of quantity and quality of production, skill and efficiency. Subjects participating in a study on the ergonomics of tea-leaf plucking operations were so categorised, and the results have been compared with the existing groupings followed by the Tea-estate authorities. Such a method could facilitate predictive selection of pluckers, selection for training, and formation of groups in future studies.

Journal Article↗
PubMedDate not supplied

Cardiac instrument development in a low-literacy population: the revised Chest Discomfort Diary.

OBJECTIVE: The purpose of this study was to pilot test a self-administered chest pain questionnaire, a revised version of the Chest Discomfort Diary (CDD-R), in a sample of patients with chronic angina selected from a population known to have low literacy. DESIGN: The study design was descriptive and correlational. SAMPLE: The study used a convenience sample of 27 subjects with documented history of coronary artery disease and angina. Characteristics of the sample included a mean age of 56.3 years (SD, 12.4 years), 88.9% African-American, and 56.3% male, and 59.3% had a history of acute myocardial infarction. Approximately 28% had achieved a 9th-grade education or less, and reading levels ranged from 4th grade to 12th grade. Subjects completed the CDD-R, a 36-item instrument reflecting multiple dimensions of anginal chest pain. RESULTS: Descriptions of the location (left chest, 66.6%), character (pressure, 59.2%), and precipitants of chest pain (walking, 51.8%) were consistent with clinical descriptions of "typical angina." Other physical symptoms such as shortness of breath (88.8%) and fatigue (85.1%) were reported. Walking (55.5%) was the activity most frequently described as difficult to perform because of chest pain, with sublingual nitroglycerin (77.7%) the most frequently used and most effective chest pain relief strategy. CONCLUSION: The CDD-R adequately measured multiple characteristics of anginal chest pain. Further research is needed to establish construct validity of the CDD-R and to determine the feasibility of using the instrument to monitor changes over time in patients' chronic angina.

Adult↗
PubMedDate not supplied

Maternal fatigue: implications of second stage labor nursing care.

The parameters of fatigue have been studied in recent years in relation to women's health and the childbearing period. Less research emphasis has been placed on second stage labor, a period of time that can encompass considerable physiologic and psychologic fatigue. Consideration to minimizing second stage labor fatigue by altering conventional support practices is needed. This includes minimizing long periods of strong pushing or bearing down efforts in conjunction with sustained breath holding, particularly for women receiving epidural anesthesia. The potential sequelae of second stage labor fatigue, recommendations for practice changes, and new research directions are discussed.

Fatigue↗