Myocardial stunning in hyperthyroidism

The cases of two patients with hyperthyroidism and acute left ventricular (LV) dysfunction with segmental wall motion abnormalities resulting in heart failure are reported. Both had electrocardiographic changes mimicking ischemic coronary artery disease. Treatment with antithyroid medications, beta blockers, and angiotensin-converting enzyme inhibitors rapidly restored LV function. The rapid reversibility suggests a role for myocardial stunning, an important entity to recognize in hyperthyroidism since this form of LV dysfunction can be reversed with appropriate treatment.

[Pathological findings in pigs affected by the postweaning multisystemic wasting syndrome in Argentina]

Postweaning multisystemic wasting syndrome was first described in Canada in 1991 and at present an increasing number of cases has been diagnosed worldwide. In Argentina the first cases of PMWS were reported recently. Forty eight 5 to 12 week old pigs with signs characteristic of PMWS from 19 farms were studied. Although the real distribution of the virus in our country is not known it was observed an increasing number of farms with PMWS distributed in the major producing provinces. The histopathology was an important tool in diagnosis of suspicious cases of PMWS with the observation of different degrees of lesion. In the studied animals, the secondary infections, either by opportunistic pathogens or secondary bacteria could be important.

Long-term outcome of preterm infants discharged home on kangaroo care in a developing country

Several hospital-based studies have shown the beneficial effect of kangaroo care on preterm infants. Long-term outcome was studied in 297 preterm infants born at Harare Hospital weighing 500-1800 g, discharged home on kangaroo care and followed up for 12 months. Of these, 79 (26.6%) died, 141 (47.5%) survived to complete follow-up and 77 (25.9%) were lost to follow-up. Of those who died, median birthweight was 1460 g, median age at hospital discharge 7 days, median weight at discharge 1400 g and median age at death 66 days. Of those who completed follow-up, median birthweight was 1575 g, median age at hospital discharge was 6 days and median weight at hospital discharge was 1500 g. Of those who were lost to follow-up, median age at loss to follow-up was 70 days, median birthweight was 1540 g, median age at hospital discharge was 5 days and median weight at hospital discharge was 1500 g. The hospital re-admission rate was 22.9% with 8.8% mortality. Maternal mortality and chronic morbidity rates were 4.7% and 7.4%, respectively. On comparing those who died with those who completed follow-up, mother's age <20 years, birthweight <1500 g and maternal mortality and chronic morbidity were significant risk factors for infant mortality. Age at discharge and weight at birth and on discharge were not significantly associated with infant mortality.

ThermoSpot in the detection of neonatal hypothermia

Thermal care is a critical part of caring for neonates. The need to identify simple, affordable and effective tools for detecting hypothermia in newborn infants that can be used by mothers and other caregivers in resource-poor countries remains crucial in our efforts to reduce perinatal and neonatal mortality and morbidity. The objective of this study was to determine the effectiveness of ThermoSpot in detecting hypothermia in newborn infants in a developing country. The prevalence of hypothermia (< 36 degrees C) in our study population was 51.4%. The ThermoSpot disc indicated green (normothermia) in 82% of infants whose axillary temperature was between 32 and 35.9 degrees C. However, the disc had a 100% specificity and positive predictive value at body temperatures below 36 degrees C and axillary temperatures below 36 degrees C or above 37.5 degrees C. Sensitivity, negative predictive value and accuracy were 19%, 52% and 57%, respectively. Mortality was significant in infants with black or blue ThermoSpot disc colours compared with green. For ThermoSpot discs placed on the abdomen, the risk of dying was 2.67 times higher if the disc colour was black compared with green and 2.43 times higher if the disc colour was blue compared with green. Similarly for ThermoSpot discs placed in the axilla, the risk of dying was 2.54 times higher if the disc colour was black and 2.5 times higher if the disc colour was blue as opposed to green. There is a need to improve the sensitivity and accuracy of ThermoSpot in detecting hypothermia before its widespread use.

Production of biosurfactant from a new and promising strain of Pseudomonas aeruginosa PA1

The Pseudomonas aeruginosa PA1 strain, isolated from the water of oil production in Sergipe, Northeast Brazil, was evaluated as a potential rhamnolipid type of biosurfactant producer. The production of biosurfactants was investigated using different carbon sources (n-hexadecane, paraffin oil, glycerol, and babassu oil) and inoculum concentrations (0.0016-0.008 g/L). The best results were obtained with glycerol as the substrate and an initial cell concentration of 0.004 g/L. A C:N ratio of 22.8 led to the greatest production of rhamnolipids (1700 mg/L) and efficiency (1.18 g of rhamnolipid/g of dry wt).

Xylanase production by Aspergillus awamori in solid-state fermentation and influence of different nitrogen sources

The use of purified xylan as a substrate for bioconversion into xylanases increases the cost of enzyme production. Consequently, there have been attempts to develop a bioprocess to produce such enzymes using different lignocellulosic residues. Filamentous fungi have been widely used to produce hydrolytic enzymes for industrial applications, including xylanases, whose levels in fungi are generally much higher than those in yeast and bacteria. Considering the industrial importance of xylanases, the present study evaluated the use of milled sugarcane bagasse, without any pretreatment, as a carbon source. Also, the effect of different nitrogen sources and the C:N ratio on xylanase production by Aspergillus awamori were investigated, in experiments carried out in solid-state fermentation. High extracellular xylanolytic activity was observed on cultivation of A. awamori on milled sugarcane bagasse and organic nitrogen sources (45 IU/mL for endoxylanase and 3.5 IU/mL for beta-xylosidase). Endoxylanase and beta-xylosidase activities were higher when sodium nitrate was used as the nitrogen source, when compared with peptone, urea, and ammonium sulfate at the optimized C:N ratio of 10:1. The use of yeast extract as a supplement to the these nitrogen sources resulted in considerable improvement in the production of xylanases, showing the importance of this organic nitrogen source on A. awamori metabolism.

Synthesis, characterization and biodistribution of bisphosphonates Sm-153 complexes: correlation with molecular modeling interaction studies

Bisphosphonates (BPs) are characterized by a P-C-P backbone structure and two phosphonic acid groups bonded to the same carbon, and are established as osteoclast-mediated bone resorption inhibitors. The nature of the groups attached to the central carbon atom are responsible in determining the potency of bisphosphonates as anti-resorption drugs. However, it is not yet clear the exact relationship between their molecular structure and pharmacologic activities. In this study, molecular geometries of pamidronate, alendronate and neridronate, differing only in the length of the aliphatic chains, were predicted by molecular mechanics and their interactions with hydroxyapatite, the main bone mineral component, were examined. We report the synthesis and radiochemical characterization of 153Sm complexes with pamidronate, alendronate and neridronate. Hydroxyapatite binding and biodistribution studies of these complexes have shown a good correlation with the theoretical molecular modeling interaction studies. So, it is possible to conclude that computational chemistry techniques are a good approach to evaluate specific interactions and may play a relevant role in determining the relative ability of BPs to mineral bone, and open new perspectives to the design of new BPs with increased pharmacological activity. These techniques could be extended to BPs as ligands to carrier radioactive metals, aiming for new bone therapeutic radiopharmaceuticals.

[Dyspepsia in general practice consultation]

An observational descriptive transversal study was carried out to analyse the clinical log-books of the patients with dyspeptic complaints in the General Practice consultation of Fernão de Magalhães Heath Center, during 1994. The aim of the study was to assess: the distribution of dyspeptic categories; the association of dyspepsia groups and the selected variables; the identified risk factors; the clinical investigation and its relationship with the age groups, as well as prescription in the General Practice consultations. The results of the study show that: functional dyspepsia is more frequent than organic; females have functional dyspepsia more frequently, with a statistically significant difference; there are more consultations with dyspeptic complaints among the elderly; about 50% of the patients with dyspeptic symptoms were investigated and two thirds were above forty-five years of age; the prescribed medication was similar to that recommended.

Identification of severe right ventricular dysfunction by technetium-99m-sestamibi gated SPECT imaging

An 84-yr-old man with previous anterior wall myocardial infarction presented with shortness of breath and palpitations. His symptoms were attributed to myocardial ischemia, and he was referred for a stress 99mTc-sestamibi SPECT imaging study with gating. The images showed minimal left ventricular ischemia, but a dilated and hypokinetic right ventricle suggested pulmonary pathology as the probable etiology of his presenting symptoms. A subsequent ventilation perfusion study was consistent with the diagnosis of multiple pulmonary emboli. Thus, 99mTc-sestamibi SPECT imaging with gating provides information about right ventricular perfusion and function, enhancing the clinical utility of stress myocardial perfusion imaging.

Arterial and venous signs of tumors within the fourth ventricle

A positive diagnosis of tumors located within the fourth ventricle should be based on specific signs therby excluding other space occupying lesions in the posterior fossa. These are a typical omega form of the hemispheric cerebellar branches on the lateral projection, and an also typical inverted 3 form of the PICA in the semiaxial projection. Alteration of the veins of the lateral recess of the fourth ventricle and of the precentral cerebellar vein are important venous signs. Indirect signs are found in the absence of tonsillar herniation with arterial and venous signs of AP stretching of the cerebellar tonsils.