Blunt trauma resuscitation: the old can respond.

Hypothesis: Old and young trauma patients are capable of hyperdynamic response during standardized shock resuscitation.

Design: The responses of old and young trauma patients resuscitated using a standardized protocol are compared in an inception cohort study. A standardized resuscitation protocol was used to attain and maintain an oxygen delivery index of 600 mL/min x m2 or greater (DO2I > or = 600) for the first 24 hours in the intensive care unit.

Natural estrous cycle in normal and diabetic bitches. II). Serum nonesterified fatty acids and serum free glycerol levels during glucose and insulin tests.

Actions and interactions of spontaneous diabetes mellitus (DM) and natural estrous cycles (sex seasons) on the regulation of serum nonesterified fatty acids (NEFAs) and free glycerol (FG) levels in bitches in the fasting condition and during i.v. glucose (IVGTT) and insulin (ITT) tolerance tests, were studied.

Screening and characterization of Bacillus thuringiensis isolates from Brazil for the presence of coleoptera-specific cry genes.

Forty-three Bacillus thuringiensis isolates from Brazil and 3 from Argentina were screened, using the polymerase chain reaction (PCR), for various coleoptera-specific cry genes. Seven isolates produced specific and/or nonspecific DNA fragments in a PCR reaction with primers specific for two coleopteran cry genes and 4 of these produced DNA fragments with primers specific for 7 known coleopteran cry genes. These isolates showed, by electron microscopy, the presence of spherical crystals.

Site-directed mutagenesis of Cys-92 from the alpha-polypeptide of Phaseolus vulgaris glutamine synthetase reveals that this highly conserved residue is not essential for enzyme activity but it is involved in thermal stability.

The residue Cys-92 from the alpha-polypeptide of Phaseolus vulgaris glutamine synthetase is a highly conserved residue in prokaryotic and eukaryotic glutamine synthetase genes. This cysteine residue was previously proposed as a good candidate for being essential for enzyme activity. We have examined through heterologous expression in Escherichia coli and site-directed mutagenesis the functional importance of this residue.

Efficacy of computerized decision support for mechanical ventilation: results of a prospective multi-center randomized trial.

200 adult respiratory distress syndrome patients were included in a prospective multicenter randomized trial to determine the efficacy of computerized decision support. The study was done in 10 medical centers across the United States. There was no significant difference in survival between the two treatment groups (mean 2 = 0.

Functional importance of Asp56 from the alpha-polypeptide of Phaseolus vulgaris glutamine synthetase. An essential residue for transferase but not for biosynthetic enzyme activity.

Replacement of Asp56 by site-directed mutagenesis of the alpha-gene from Phaseolus vulgaris glutamine synthetase heterologously expressed in Escherichia coli produces a complete loss of transferase enzyme activity, thus revealing essentiality of the residue for this particular enzyme activity. This happens independent of Asp56 being replaced by Ala or Glu, suggesting that the essentiality of this residue cannot be attributed to its negative electrical charge. However, a high level of glutamine synthetase biosynthetic specific activity (referred to glutamine synthetase protein, as determined immunologically), is present in D56A and D56E mutants, suggesting that Asp56 is an example of a residue that has a different role in the catalytic mechanism of both enzyme activities of this protein.

Site-directed mutagenesis of Glu-297 from the alpha-polypeptide of Phaseolus vulgaris glutamine synthetase alters kinetic and structural properties and confers resistance to L-methionine sulfoximine.

In this paper we examine the functionality of Glu-297 from the alpha-polypeptide of Phaseolus vulgaris glutamine synthetase (EC 6.3.1.

Thioacetamide effects on the polypeptidic and nucleoporin pattern and chemical composition of rat liver nuclear envelope subfractions.

The effect of the administration of seven doses of the hepatocarcinogen thioacetamide on the chemical composition of rat liver nuclear envelope subfractions: associated chromatin, nuclear membranes and pore complex-lamina fraction, is analyzed. No alteration in DNA, RNA or phospholipid content is observed after the hepatocarcinogen treatment. Electrophoretic studies of each subfraction from thioacetamide treated rats show differences in the relative proportions of some polypeptides when compared with the controls.

Increase of a calcium independent transglutaminase activity in the erythrocyte during the infection with Plasmodium falciparum.

We have studied the activity of a calcium dependent transglutaminase (EC 2.3.2.

Adsorption of Acetone onto MgO: Experimental and Theoretical Evidence for the Presence of a Surface Enolate.

A new band at 1640 cm is revealed by diffuse reflectance FT-IR spectroscopy of acetone adsorbed on a MgO surface (shown schematically). On the grounds of ab initio quantum-mechanical calculations, this band is assigned to an adsorbed enolate species. This evidence proves the catalytic role of the metal oxide surface in the condensation reaction mechanism.

Ultrastructure of hepatocyte abnormalities in perimetastatic areas.

The ultrastructural pathology of non-invaded hepatocytes located in close proximity to metastases from diverse gastrointestinal carcinomas was studied. Observed abnormalities included swelling of rough and smooth endoplasmic reticulum, proliferation of lysosomes, and mitochondrial alterations as presence of granules and paracrystalline inclusions, marked pleomorphism, and lack of cristae. These results show that, contrary to the classical conception, the non-invaded cells surrounding primary tumours or their metastases could be abnormal.

Liver ultrastructural pathology in mice infected with Plasmodium berghei.

As liver can be an important target organ in malaria, we performed an ultrastructural study of hepatic alterations in the final stage of Plasmodium berghei infection in mice. Significant hepatocyte abnormalities were found. An elevated number of cells showed mitochondria with a high electron-dense matrix and multiple changes in shape and size, alterations in the structure of Golgi complex, swelling and disorganisation of both rough and smooth-surfaced endoplasmic reticulum, differently shaped peroxisome nucleoids, and disappearance of glycogen granules.

Ultrastructure of hepatic metastases from a colon leiomyosarcoma.

The electron microscopic examination of biopsies from liver metastases of a colon leiomyosarcoma showed the existence of alterations not previously reported in primary tumors of that kind. Those abnormalities included proliferation of lysosomal structures as multivesicular bodies, myelin-like figures, lipofuscin granules and autophagic vacuoles, along with mitochondrial changes as concentric and vesiculated cristae, and presence of dense granules and elongated inclusions. This study suggests that, in this tumor and host tissue, the so-called invasive phenotype, which is supposed to form the metastases, could have a distinct morphological picture at the ultrastructural level.

Regulation of the expression of ferredoxin-glutamate synthase in barley.

We have investigated the regulation of ferredoxin-glutamate synthase (Fd-GOGAT) in leaves of barley (Hordeum vulgare L. cv. Maris Mink) at the mRNA, protein and enzyme activity levels.

Both the catalytic and regulatory domains of protein kinase C chimeras modulate the proliferative properties of NIH 3T3 cells.

Protein kinase C (PKC) isozymes exhibit important differences in terms of their regulation and biological functions. Not only may some PKC isoforms be active and others not for a given response, but the actions of different isoforms may even be antagonistic. In NIH 3T3 cells, for example, PKCdelta arrests cell growth whereas PKCepsilon stimulates it.

The catalytic domain of protein kinase C chimeras modulates the affinity and targeting of phorbol ester-induced translocation.

Emerging evidence suggests important differences among protein kinase C (PKC) isozymes in terms of their regulation and biological functions. PKC is regulated by multiple interdependent mechanisms, including enzymatic activation, translocation of the enzyme in response to activation, phosphorylation, and proteolysis. As part of our ongoing studies to define the factors contributing to the specificity of PKC isozymes, we prepared chimeras between the catalytic and regulatory domains of PKCalpha, -delta, and -epsilon.

Microvascular pathology in the skeletal muscle paraneoplastic phenomenon.

An electron microscopic investigation was made in order to study capillary alterations in the muscle paraneoplastic phenomenon associated with different malignant tumours. Several abnormalities were found including basement membrane widening and lamination, endothelial hypertrophy, a varied degree of lumen occlusion, and proliferative changes in pericytes. A degenerative process leading to capillary necrosis was also observed.

Natural estrous cycle in normal and diabetic bitches in relation to glucose and insulin tests.

The influence of spontaneous "sex seasons" on blood sugar (BS) and serum insulin levels was studied in bitches with natural diabetes mellitus (DM) and normal controls, in the basal condition and during glucose and insulin tests, was studied. DM increased basal BS, reduced glucose tolerance, distribution space (DS) and clearance from blood, and induced resistance to insulin hypoglycemic action. In normals occurrence of "seasons", inconsistently modified basal BS, increased glucose tolerance and DS; during estrogenic phase (EP), these variables were above those during luteal phase (LP).

Adrenal cortex alterations in mice infected with Plasmodium berghei.

The ultrastructural study of adrenal cortex from Plasmodium berghei infected mice showed different degrees of capillary wall alterations including disruption and widening of the fenestrae, capillaries packed with parasitized erythrocytes, necrosis of cortical cells, parasitized erythrocytes outside capillaries and in some instances inside cortical cell cytoplasm. Lymphocytes were also observed in degenerated cortical cells. Our results suggest that adrenal cortex lesions may be relevant in the etiopathogenesis of severe malaria.

Skeletal muscle pathology in mice experimentally infected with Toxoplasma gondii.

In two different groups of mice, the infection with Toxoplasma gondii was produced by intraperitoneal route, with 2 x 10(5) parasites (n = 8) and 14 x 10(5) parasites (n = 3). Five days after infection animals were killed to examine skeletal muscles by light and transmission electron microscopy. Severity of muscle alterations depended upon concentration of parasites.

Skeletal muscle ultrastructural pathology in Serinus canarius infected with Plasmodium cathemerium.

Serinus canarius infected with Plasmodium cathemerium was used as an animal model in order to study the skeletal muscle compromise in malaria. Pectoral muscle biopsies were obtained from 7 infected female birds. The transmission electron microscopic study showed alterations of contractile and sarcotubular systems, mitochondrial abnormalities, lysosomal proliferation and nuclear pyknosis.

Toxic and neurogenic factors in chloroquine myopathy fibre selectivity.

Biopsies from soleus and extensor digitorum longus (EDL) muscles obtained in rats with an experimental chloroquine myopathy were studied ultrastructurally. Two different histopathological pictures were observed: type I fibres from soleus exhibited a vacuolar myopathy with an almost normal sarcomeric structure; type II fibres from EDL did not show vacuoles but changes similar to neurogenic atrophy. Our results suggest that chloroquine produces direct toxic effects in type I fibres and secondary neurogenic damage in type II fibres.