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Biomedical subjects

P Torres

Publications and source records attributed to P Torres.

At least 55 records · Page 3Linked to original sources

Factors associated with Taenia solium cysticercosis: analysis of nine hundred forty-six Peruvian neurologic patients. Cysticercosis Working Group in Peru (CWG).

In most developing countries, 10% of acute neurologic cases are patients with neurocysticercosis (NCC). Determining specific factors associated with contracting NCC will facilitate its diagnosis and prevention. We examined multiple socioeconomic, demographic, environmental, medical, and behavioral characteristics of 946 Peruvian neurologic patients for a correlation with NCC, which was diagnosed by the highly specific and sensitive electroimmunotransfer blot (EITB) or immunoblot assay. Eighteen percent (172 of 932) of serum samples and 28% (101 of 362) of cerebrospinal fluid samples were EITB-positive. The proportion of EITB-positive persons was similar for all socioeconomic levels. Significant factors associated with NCC were: 1) being born outside Lima, 2) having raised pigs, 3) more than 20 years of age, 4) a history of seizures, and 5) a history of taeniasis. Of these factors, raising pigs is the only one that is amenable to intervention, via improvements in animal husbandry.

Adolescent↗

[Blood fractionation based on the extraction of the buffy-coat layer. Analysis of our results].

PURPOSE: To compare a procedure of blood processing via a quadruple bag for the preparation of white-cell-poor blood components with the results obtained with triple-bag-system, in order to adopt it as routine in our blood centre. MATERIAL AND METHODS: Blood was collected in 289 quadruple-bag-system containing 63 mL of CPD as anticoagulant and 100 mL of SAG M solution as additive for the red cells. We used 237 standard quadruple-bags supplied by Fenwal (195) and NPBI (42), and 52 of the top-and-bottom system supplied by Fenwal. Blood separation was made automatically by CompomatR (NPBI) and platelet concentrates were prepared from the buffy-coat fraction. Standard bags were processing as follows: After the first centrifugation of the whole blood (28,800 g), the plasma was transferred into the 300-mL bag until the interface of red cells and plasma was detected; then approximately 80 mL of plasma and buffy-coat (BC) were collected into the 100-mL satellite bag. Top-and-bottom bags were centrifuged at 43,500 g., the red-cells were transferred into the bottom-bag containing SAGM, and plasma was transferred into the top-bag. The buffy-coat fraction remains in the original bag. In both procedures, platelet concentrates were prepared from buffy-coat fraction. After the centrifugation of this fraction (1,400 g and 1,600 g), the supernatant (concentrated platelets in plasma) was transferred into a 300-mL bag and the bag with the residual buffy-coat was then discarded. 287 triple-bags were separated in the traditional way, using platelet-rich plasma (PRP) as a source for the preparation of platelet concentrate (PC). Volumes were measured by weigh and specificity gravity. Platelet, leukocytes and red-cells were counted in the Coulter-Counter (STKR.Izasa). T-Student test and Chi2 test were used for statistical analysis and p < 0.05 was taken as a significant difference between samples. RESULTS: The three kinds of quadruple-bags showed results very homogeneous with little differences. For all brand of bags packed-red-cells showed a volume of 300 +/- 2.9 mL, EVF of 51.9 +/- 0.7%. The recovery of red cells into the packed red cells and of platelets into the platelet concentrate was 90 +/- 0.4 percent and 69 +/- 2 percent respectively, of the original value. White cells in the packed red cells were 9.7 +/- 03 x 10(9) with recovery of 30.1 +/- 1.4 percent of the original value; statistical difference was found in comparison with triple bags PRC (p < 0.001). The PC volumes averaged 71 +/- 1 mL and the overall mean platelet concentration was 77 +/- 2 x 10(9). Eighty three percent of PC contained more than 55 x 10(9). White cells contamination of platelet concentrates was 0.283 +/- 0.039 x 10(9), with a recovery of 9.5 +/- 1.5 percent of the leukocytes present in the whole blood. This value is below the threshold that prevents febrile reactions and microaggregate formation. The plasma yield in the quadruple-bag system was much greater than that in the triple-bag system (p < 0.001). With this process we removed about 77 +/- 0.5 percent of the plasma present in the original unit in comparison with 56 +/- 1 percent removed in that of the triple-bag system. CONCLUSION: With this procedure leukocyte-poor blood components are obtained in which more of 90 percent original white cells have been removed, with a red-cell recovery of 90 percent. Moreover, the plasma yield is also excellent.

Blood Platelets↗

Seasonal variation of LH and testosterone in the smallest deer, the pudu (Pudu puda molina) and its relationship to the antler cycle.

1. In order to obtain a seasonal profile of LH, three adult male pudu (Pudu puda, Molina) were sampled monthly from the saphenous vein for a period of one year. 2. A significant circannual variation of plasma LH levels was detected with an average peak value (1.77 ng/ml) recorded in February and nadir concentrations (0.19 ng/ml) observed in November. 3. The peak level of testosterone (1.54 ng/ml) was detected in March, the time of the rut.

Animals↗

Causes of increasing pericardial pressure in experimental cardiac tamponade induced by ventricular perforation.

It has been shown that the intravenous infusion of saline solution in a dog with stabilized cardiac tamponade produced an increase in pericardial pressure. To demonstrate that this pressure increase is the result of bleeding into the pericardial sac, an experimental study was conducted, consisting of the injection of red cells marked with 51Cr during the intravenous infusion of saline solution in dogs with and without progressive tamponade. The results showed that in the dogs without progressive tamponade, both the pericardial pressure and the red cell count in the pericardial cavity remained stable during the infusion of saline solution, whereas in dogs with progressive tamponade, the numbers of marked cells and the pericardial pressure increased significantly, following a similar pattern.

Animals↗

Preliminary evaluation of a simple method for detection of bovine tuberculosis: the glutaraldehyde test.

The glutaraldehyde test (GT) is performed by mixing whole blood with a 1.25% glutaraldehyde solution. Gelification time is shorter in tuberculous cattle. This test was performed in blood samples obtained from: (a) 48 cattle with bacteriologically confirmed tuberculous lesions; (b) 61 animals with no evidence of tuberculosis at the time of slaughterhouse inspection, 14 of which had hydatid cysts; (c) 260 tuberculin-negative apparently healthy animals, and (d) 21 cattle, also tuberculin-negative but serologically positive for brucellosis. Sensitivity for detecting tuberculosis was 85.4% (41 of 48 animals). The test was negative in 298 out of 307 healthy animals (97.1% specificity). This specificity decreased when the test was applied in animals with evidence of diseases other than tuberculosis. This simple, rapid and inexpensive method could play a complementary role to the tuberculin test for detecting tuberculous cattle, especially in endemic areas with scarce resources and facilities.

Animals↗

An investigation of the rheological properties of 10 vinyl-polysiloxane impression materials.

PURPOSE: The time required for 10 vinyl-polysiloxane impression materials to reach a viscosity of 5000 poise (Tcv) was estimated. This viscosity was selected based on previous work that suggested that an impression material might not be workable if its viscosity exceeded this limit. The effect of variations in the time of placement of the impression materials into a simulated oral-temperature environment was also studied. MATERIALS AND METHODS: The change in the viscosity of the impression materials was recorded with a viscometer at oral temperature. Impression materials were placed at either 20 seconds, 30 seconds, or 40 seconds from the start of mixing. RESULTS: There were statistically significant differences in Tcv among various impression materials. Variations in placement time significantly affected the Tcv of six impression materials. CONCLUSIONS: Knowledge of the viscosity change of an impression material is beneficial in the clinical selection of an impression material.

Analysis of Variance↗

Immunodiagnosis of human cysticercosis (Taenia solium): a field comparison of an antibody-enzyme-linked immunosorbent assay (ELISA), an antigen-ELISA, and an enzyme-linked immunoelectrotransfer blot (EITB) assay in Peru. The Cysticercosis Working Group in Peru (CWG).

We compared results of an enzyme-linked immunosorbent assay (ELISA) and an enzyme-linked immunoelectrotransfer blot (EITB) assay for the diagnosis of cysticercosis in sera and cerebrospinal fluid (CSF). Sera from 34 patients with confirmed cysticercosis were tested by both ELISA and EITB assays. Cerebrospinal fluid from some of these patients was also tested by ELISA for the presence of antibody (AB-ELISA) (n = 21) and antigen (AG-ELISA) (n = 15). Specificity in sera was examined by testing 51 serum samples from Bangladesh, where cysticercosis is not endemic. Cross-reactivity was evaluated in sera from patients with Echinococcus granulosus (hydatid) and Hymenolepis nana infections. Sensitivity in detecting cysticercosis in sera was 94% by EITB and 65% by AB-ELISA (P less than 0.01). Sensitivities in the CSF tested by EITB, AB-ELISA, and AG-ELISA were 86%, 62%, and 67%, respectively. The specificity of the EITB was 100%, while that of AB-ELISA was 63% (P less than 0.01). Cross-reactions occurred in the AB-ELISA with 11% and 20% of sera from hydatid and H. nana patients, respectively. Our results demonstrate that the EITB is the best assay available for the diagnosis of cysticercosis in both sera and CSF.

Animals↗

Gastrointestinal helminths of the cetaceans Phocoena spinipinnis (Burmeister, 1865) and Cephalorhynchus eutropia (Gray, 1846) from the southern coast of Chile.

Gastrointestinal helminths of the cetaceans Cephalorhynchus eutropia and Phocoena spinipinnis accidentally entangled in gillnets off the coast of Queule, Chile, were identified from 1989 to 1990. Pseudoterranova sp., Polymorphus (Polymorphus) cetaceum and Synthesium tursionis occurred in both cetaceans. Additionally, Anisakis sp. and Braunina cordiformis were found in C. eutropia, and Anisakis simplex was identified from P. spinipinnis. The species with the highest prevalence and mean intensity of infection in P. spinipinnis and C. eutropia were P. (P.) cetaceum and B. cordiformis, respectively. The diet of both cetaceans consists mainly of fishes.

Animals↗

Experimental cardiac tamponade with a myocardial wound: the effect of rapid intravenous infusion of saline.

In order to demonstrate that the evolution of cardiac tamponade from a ventricular wound is different from that without myocardial wounding, the effects of a rapid infusion of saline solution on hemodynamic behavior and pericardial pressure (PP) were evaluated in dogs with cardiac tamponade caused by ventricular perforation (group C), animals without cardiac tamponade (group A), and animals with cardiac tamponade induced by infusion of saline into the pericardium (group B). We found that blood pressure (BP) increased from 107.5 +/- 15.5 mm Hg to 126 +/- 4 mm Hg in group A; increased from 64.5 +/- 17.9 mm Hg to 117.5 +/- 22.17 mm Hg in group B; and increased from 60.75 +/- 46.5 mm Hg to 76 +/- 14.4 mm Hg in group C. Central venous pressure (CVP) increased from 3.75 +/- 0.96 cm H2O to 9.5 +/- 3.3 cm H2O in group A; increased from 8 +/- 2.4 cm H2O to 16.25 +/- 3.1 cm H2O in group B; and rose from 7.75 +/- 2.6 cm H2O to 20.66 +/- 5.03 cm H2O in group C. Cardiac output (CO) increased from 3.9 +/- 1.2 L/min to 18.93 +/- 3.96 L/min in group A; increased from 1.23 +/- 0.3 L/min to 5.4 +/- 1.7 L/min in group B; and increased from 1.8 +/- 0.66 L/min to 3.53 +/- 1.31 L/min in group C.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Gastrointestinal helminths of fish-eating birds from Chiloe Island, Chile.

Of four species of fish-eating birds from Chiloé Island (Chile), three were infected with eight species of helminths. Tetrabothrius sp. was found in Larus scoresbii. Tetrabothrius cylindraceus, Profilicollis antarcticus, Anomotaenia dominicanus, Stephanoprora denticulata, Capillaria sp. and P. antarcticus were found in Larus dominicanus. Contracaecum rudolphii and Corynosoma sp. infected Phalacrocorax olivaceus. With the exception of S. denticulata, C. rudolphii and Capillaria sp., the above helminths are reported for the first time from Chile.

Animals↗

Humoral immunity in different phases of contact dermatitis.

Although cell-mediated hypersensitivity seems to be the main immunological response of man in contact dermatitis, recent studies suggest the potential involvement of antibody-mediated and basophilic cutaneous hypersensitivity in the physiopathology of this affection. The aim of this work was to contribute data intended to clarify the possible involvement of factors traditionally assigned to humoral hypersensitivity in the pathology of contact dermatitis. For this purpose blood levels of the different immunoglobulins were determined in patients with contact dermatitis. Three phases were considered, namely, one in which the patients showed typical clinical signs (acute phase), another in which the lesions had subsided (intercrisis phase) and a third in which the signs had recurred (acute outbreak). All those patients who concomitantly suffered from or had any personal or family antecedents of type I hypersensitivity were excluded from the study. The results found were compared with those obtained for a control gorup consisting of healthy individuals with no atopic antecedents. No significant differences were found between the results obtained in the three phases. However, the IgE levels of the patients were significantly higher than those of the control group, whereas the differences in the IgE, IgA and IgM levels were insignificant.

Acute Disease↗

Cadmium induction of metallothioneins in several dogfish organs.

Dogfish Scyliorhinus canicula were exposed to 50 mg/l Cd for 4 days for inducing metallothionein synthesis. Spleen, pancreas, kidney and gonads were dissected out and metallothionein presence was checked by means of gel filtration chromatography in Sephadex G-75 and sodium dodecyl sulphate polyacrylamide electrophoresis. In pancreas and kidney, a cadmium-binding protein with spectroscopical and electrophoretic properties similar to those of dogfish liver metallothionein was found. In the other organs, the existence of an analogue protein but at very low concentrations is feasible.

Animals↗

Mycobacterium vaccae in immunoprophylaxis and immunotherapy of leprosy and tuberculosis.

Both leprosy and tuberculosis present continuing problems in their control, especially in the developing world, despite the availability of drugs effective in producing a bacteriological cure. Improved immunoprophylaxis, and an effective immunotherapy to be used with chemotherapy are urgently required. Intradermal injection of a suspension of killed Mycobacterium vaccae promotes cell-mediated responses to antigens common to all mycobacteria, and switches off the tissue-necrotizing aspects of the Koch phenomenon. These properties led to the use of the suspensions as an improved vaccine, either alone or in combination with BCG. The same properties led to the employment of the suspension in immunotherapy as an adjunct to chemotherapy in the treatment of both leprosy and tuberculosis. The evidence leading to these conclusions is reviewed and discussed.

Animals↗

Comparative study of the behavioral changes evoked by d-amphetamine and apomorphine in adult cats. Dose-response relationship.

The behavioral effects of d-amphetamine and apomorphine administration were studied in 17 adult cats. The doses of amphetamine administered were 0.1, 0.5, 1.0 and 5.0 mg/kg; those of apomorphine, 0.1, 0.5, 1.0 and 2.0 mg/kg. These two drugs evoked in the same animal marked differences in behavioral responses. Amphetamine induced a dose-dependent hypomotility, which was marked with the higher doses. In addition, rhythmic, bilateral slow movements of the head as a mode of stereotypy, indifference to the environment and dose-dependent increase in respiratory rate. Apomorphine elicited limb flicking, dose-dependent hypermotility and increase in olfactory behavior, the last two reactions with stereotypy characteristics. The animals appeared as if being scared, hyperreacting to sudden stimuli and showing total indifference to the surrounding environment. There were marked differences in behavioral responses evoked by these two agonists of the catecholaminergic system. These data do not conform with the behavioral reactions reported in the rat by other investigators. The disagreement with other communications is probably due to differences in reactivity of the species employed. The processes involved in the diversity of the behavioral responses of the cat to the administration of amphetamine and apomorphine have not been delucidated.

Animals↗

[Epidemiology of diphyllobothriasis in the Valdivia river basin, Chile].

In the Valdivia (Chile) river basin 1,295 inhabitants of 6 riverside districts were examined between March and October 1987 and showed a 1.2% of prevalence by Diphyllobothrium in the districts of Riñihue and Las Huellas. Prevalence of 5.3% and 9.8% respectively were registered in dogs of the districts of Riñihue and Malihue. No cat or pig infection was observed in the different districts. The parasites recovered after the treatment were identified as Diphyllobothrium latum. Human infection by D. latum in the districts affected results from the consumption of smoked or insufficiently cooked fish. The investigation of 1,450 fish (4 exotic species and 11 autochthonous ones), caught in the Valdivia river basin in 1986 and 1987, showed the existence of plerocercoids of D. latum and/or Diphyllobothrium dendriticum in Salmo gairdneri and Salmo trutta among exotic fish and in some autochthonous species. Prevalence and mean intensity in the infection of fish as well as the degree of aggregation in the infrapopulations varied in the different districts. Some species of fish would act as intermediary hosts and others as paratenic hosts in the life cycles of Diphyllobothrium spp. in the Valdivia river basin. An improvement in the conditions of basic sanitation, in sanitary education and in the treatment of infected persons is proposed as a means for the control of diphyllobothriasis in the districts affected.

Adult↗