Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with doppler echocardiography

OBJECTIVE: To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS: Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS: Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89cm vs.0.64cm; systolic: 0.72cm vs. 0.33cm) and left atrium (0.55cm vs. 0.33cm); thinning of left ventricular anterior wall (systolic: 0.14cm vs. 0.23cm, diastolic: 0.11cm vs. 0.14cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction. CONCLUSION: Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.

Female alcoholics: electrocardiographic changes and associated metabolic and electrolytic disorders

OBJECTIVE: To identify the electrocardiographic changes and their associations with metabolic and electrolytic changes in female alcoholics. METHODS: The study comprised 44 female alcoholics with no apparent physical disorder. They underwent the following examinations: conventional electrocardiography; serologic tests for syphilis, Chagas' disease, and hepatitis B and C viruses; urinary pregnancy testing; hematimetric analysis; biochemical measurements of albumin, fibrinogen, fasting and postprandial glycemias, lipids, hepatic enzymes, and markers for tissue necrosis and inflammation. RESULTS: Some type of electrocardiographic change was identified in 33 (75%) patients. In 17 (38.6%) patients, more than one of the following changes were present: prolonged QTc interval in 24 (54.5%), change in ventricular repolarization in 11(25%), left ventricular hypertrophy in 6 (13.6%), sinus bradycardia in 4 (9.1%), sinus tachycardia in 3 (6.8%), and conduction disorder in 3 (6.8%). The patients had elevated mean serum levels of creatine phosphokinase, aspartate aminotransferases, and gamma glutamyl transferase, as well as hypocalcemia and low levels of total cholesterol and LDL-cholesterol. The patients with altered electrocardiograms had a more elevated age, a lower alcohol consumption, hypopotassemia, and significantly elevated levels of triglycerides, postprandial glucose, sodium and gamma glutamyl transferase than those with normal electrocardiograms. The opposite occurred with fasting glycemia, magnesium, and alanine aminotransferase. CONCLUSION: The electrocardiographic changes found were prolonged QTc interval, change in ventricular repolarization, and left ventricular hypertrophy. Patients with normal and abnormal electrocardiograms had different metabolic and electrolytic changes.

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

Background: Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients. Objective: To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations. Methods: This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years) with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior® device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound. Results: The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01) and triglycerides (p = 0.02); intima-media thickness, to age (p < 0.01); diameter, to creatinine (p = 0.03) and age (p = 0.02); relative distensibility, to age (p < 0.01) and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively). Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01) and with relative distensibility (p < 0.01), while diameter showed a positive correlation with distensibility (p = 0.03). Conclusion: In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic blood pressure related to the carotid functional measure. The carotid artery structure was directly related to aortic stiffness, which was inversely related to the carotid artery functional property.

Schistosoma mansoni: structural damage after treatment with oxamniquine

The effects of a single dose (100 mg/kg-body weight of mouse) of oxamniquine on the worm's tegument and paranchyma in relation to the process of immunological granulomatous reaction of the host's liver are described under light and electron microscopy (EM). The lesions caused by the drug are sequentially and simultaneously described in form of swelling, surface bulble and disruption with erosions. Ulceration in the tubercules with loss of spines is often more extensive and severe in male worms and concentration of host's mononuclear cells is observed. The possible role of host's immune response is discussed.

Immunological abnormalities of acquired immunodeficiency syndrome and related disorders in patients from Rio de Janeiro, Brazil

The immunoloical profile of acquired immunodeficiency syndrome (AIDS) and chronic lymphadenopathy syndrome (CLAS) in 15 and 11 Brazilian patients, respectively, was studied. The AIDS patients showed reduced percentage of total T (CD3) and T-helper-inducer (CD4) lymphocytes, relative increase in numbers of T-suppressor-cytotoxic (CD8) cells and a marked inversion of T-helper-inducer/suppressor-cytotoxic (CD4/CD8) ratio. Lymphoproliferative responses to PHA, ConA, PPD and PWM were diminished. Hypergamaglobulinemia and high levels of circulating immune complexes were also found. The CLAS patients also showed important immunological alterations, but not so intense as those with AIDS. These data seems to be similar to those observed in other parts of the world.

Methodology in structural determination and synthesis of insect pheromone

By means of ethereal washing of insect pheromone glands of female moths, GC-MS detection along with microchemical reactions and electroantennogram (EAG) survey, six economically important insect species were targeted for pheromone identification. The discovery of a natural pheromone inhibitor, chemo-selectivity and species isolation by pheromone will be described. The modified triple bond migration and triethylamine liganded vinyl cuprate were applied for achiral pheromone synthesis in double bond formation. Some optically active pheromones and their stereoisomers were synthesized through chiral pool or asymmetric synthesis. Some examples of chiral recognition of insects towards their chiral pheromones will be discussed. A CaH2 and silica gel catalyzed Sharpless Expoxidation Reaction was found in shortening the reaction time.

Ultrasound monitoring of structural urinary tract disease in Schistosoma haematobium infection

A major advance in our understanding of the natural history of Schistosoma haematobium-related morbidity has come through the introduction of the portable ultrasound machines for non-invasive examination of the kidneys and bladder. With the use of generators or battery packs to supply power in non-clinical field settings, and with the use of instant photography or miniaturized thermal printers to record permanent images, it is possible to examine scores of individuals in endemic communities every day. Broad-based ultrasound screening has allowed better definition of age-specific disease risks in urinary schistosomiasis. Results indicate that urinary tract abnormalities are common (18% overall prevalence) in S. haematobium transmission areas, with a 2-4% risk of either severe bladder abnormality or advanced ureteral obstruction. In longitudinal surveys, ultrasound studies have shown that praziquantel and metrifonate therapy are rapidly effective in reversing urinary tract abnormalities among children. The benefits of treating adults are less well known, but research in progress should help to define this issue. Similarly, the prognosis of specific ultrasound findings needs to be clarified, and the ease of sonographic examination will make such long-term follow-up studies feasible. In summary, the painless, quick, and reproducible ultrasound examination has become an essential tool in the study of urinary schistosomiasis.

Structural organization of Trypanosoma cruzi

Since the initial description of Trypanosoma cruzi by Carlos Chagas in 1909, several research groups have used different microscopic techniques to obtain detailed information about the various developmental stages found in the life cycle of this intracellular parasite. This review describes the present knowledge on the organization of the most important structures and organelles found in the protozoan, such as the cell surface, flagellum, cytoskeleton, kinetoplast-mitochondrion complex, glycosome, acidocalcisome, contractile vacuole, lipid inclusions, the secretory pathway, endocytic pathway and the nucleus.

Prokaryotic cells: structural organisation of the cytoskeleton and organelles

For many years, prokaryotic cells were distinguished from eukaryotic cells based on the simplicity of their cytoplasm, in which the presence of organelles and cytoskeletal structures had not been discovered. Based on current knowledge, this review describes the complex components of the prokaryotic cell cytoskeleton, including (i) tubulin homologues composed of FtsZ, BtuA, BtuB and several associated proteins, which play a fundamental role in cell division, (ii) actin-like homologues, such as MreB and Mb1, which are involved in controlling cell width and cell length, and (iii) intermediate filament homologues, including crescentin and CfpA, which localise on the concave side of a bacterium and along its inner curvature and associate with its membrane. Some prokaryotes exhibit specialised membrane-bound organelles in the cytoplasm, such as magnetosomes and acidocalcisomes, as well as protein complexes, such as carboxysomes. This review also examines recent data on the presence of nanotubes, which are structures that are well characterised in mammalian cells that allow direct contact and communication between cells.

The shift from low to high non-structural protein 1 expression in rotavirus-infected MA-104 cells

A hallmark of group/species A rotavirus (RVA) replication in MA-104 cells is the logarithmic increase in viral mRNAs that occurs four-12 h post-infection. Viral protein synthesis typically lags closely behind mRNA synthesis but continues after mRNA levels plateau. However, RVA non-structural protein 1 (NSP1) is present at very low levels throughout viral replication despite showing robust protein synthesis. NSP1 has the contrasting properties of being susceptible to proteasomal degradation, but being stabilised against proteasomal degradation by viral proteins and/or viral mRNAs. We aimed to determine the kinetics of the accumulation and intracellular distribution of NSP1 in MA-104 cells infected with rhesus rotavirus (RRV). NSP1 preferentially localises to the perinuclear region of the cytoplasm of infected cells, forming abundant granules that are heterogeneous in size. Late in infection, large NSP1 granules predominate, coincident with a shift from low to high NSP1 expression levels. Our results indicate that rotavirus NSP1 is a late viral protein in MA-104 cells infected with RRV, presumably as a result of altered protein turnover.