Acute morphological changes in guinea-pig ileum myenteric neurons after ischemia in situ with superfusion in vitro.

We evaluated changes involving the myenteric neurons of the guinea pig after different times of ischemia in situ followed by superfusion in vitro. Intestinal ischemia was produced by clamping the superior mesenteric artery and maintaining it for 5, 10, 20, 40, 80, or 160 min. Myenteric plexus-longitudinal muscle preparations from ischemic and non-ischemic portions, obtained from the same guinea pig, were dissected and mounted in organ baths containing Krebs bicarbonate solution at 37 degrees C, gassed with 95% O(2) and 5% CO(2).

Effects of bolus size and hardness on within-subject variability of chewing cycle kinematics.

This study analysed how bolus hardness and size affect within-subject variability of chewing cycle kinematics. Two independent prospective studies were performed; both tracked chin movements using an optoelectronic recording system. Computer programs identified each subject's ten most representative cycles, and multilevel modelling procedures were used to estimate variances.

Communication as a protective factor: evaluation of a life skills HIV/AIDS prevention program for Mexican elementary-school students.

Literature suggests that communication is a protective factor against high-risk sexual behavior. This study assessed the impact of a fourth-grade communication-centered life skills program on attitudes, norms, self-efficacy, behaviors, and intentions toward communication about difficult subjects. Participants included 1,581 low-income Mexican elementary-school children, divided into experimental and control groups.

Subgingival microbiota of periodontally untreated Mexican subjects with generalized aggressive periodontitis.

Background And Aim: Specific microbial profiles that may distinguish between generalized aggressive-periodontitis (GAgP) and generalized chronic-periodontitis (GCP) have, to date, not been described. The purpose of the present study was to describe the subgingival microbial composition of Mexican subjects with GAgP and compare it with that of individuals with GCP and periodontal health (PH).

Material And Methods: Seventy-seven subjects with GAgP (n=19), GCP (n=39) and PH (n=19) were selected.

Proportion of antibiotic resistance in subgingival plaque samples from Mexican subjects.

Aim: To determine the proportion of bacteria resistant to amoxicillin and doxycycline in subgingival plaque samples from Mexican subjects.

Materials And Methods: Two subgingival plaque samples were taken from 20 Mexican subjects. Samples were dispersed, diluted and plated on non-antibiotic agar plates and on plates containing 0.

Biodegradation of high 4-chlorophenol concentrations in a discontinuous reactor fed with an optimally controlled influent flow rate.

This work presents the results of the application of an optimally controlled influent flow rate strategy to biodegrade, in a discontinuous reactor, high concentrations of 4-chlorophenol used as toxic compound model. The influent is fed into the reactor in such a way as to obtain the maximal degradation rate, thus avoiding the inhibition of the microorganisms. The optimal strategy was able to manage increments of toxic concentrations in the influent up to 7,000 mg 4CP/L without any problem.

Synthesis and characterization of nanocapsules with shells made up of Al13 tridecamers.

The synthesis of samples by the sol-gel method with aluminum tri-sec-butoxide as cation precursor, 2-propanol as solvent, and sulfuric acid as hydrolysis catalyst gave rise to nanocapsules with an average diameter of 20 nm and a shell thickness of 3.5 nm. The analysis of the X-ray diffraction patterns and the 27Al MAS NMR spectra showed that the shell of the nanocapsules was made up of Al13 tridecamers ordered in a noncrystalline symmetry.

Tyrosine kinases and osmolyte fluxes during hyposmotic swelling.

Recent evidence documents the involvement of protein tyrosine kinases (TK) in the signalling network activated by hyposmotic swelling and regulatory volume decrease. Both receptor type and cytosolic TK participate as signalling elements in the variety of cell adaptive responses to volume changes, which include adhesion reactions, reorganization of the cytoskeleton, temporal deformation/remodelling of the membrane and stress-detecting mechanisms. The present review refers to the influence of TK on the activation/operation of the osmolyte efflux pathways, ultimately leading to cell volume recovery, i.

Ependymal epithelium disruption after vanadium pentoxide inhalation. A mice experimental model.

The blood-brain barrier (BBB) protects the CNS against chemical insults. Regulation of blood-brain tissue exchange is accomplished by ependymal cells, which possess intercellular tight junctions. Loss of BBB function is an etiologic component of many neurological disorders.

How are gene sequence analyses modifying bacterial taxonomy? The case of Klebsiella.

Bacterial names are continually being changed in order to more adequately describe natural groups (the units of microbial diversity) and their relationships. The problems in Klebsiella taxonomy are illustrative and common to other bacterial genera. Like other bacteria, Klebsiella spp.

Mechanisms of chloride influx during KCl-induced swelling in the chicken retina.

An increase in extracellular KCl ([KCl]o) occurs under various pathological conditions in the retina, leading to retinal swelling and possible neuronal damage. The mechanisms of this KCl o-induced retinal swelling were investigated in the present study, with emphasis on the Cl- transport mechanisms. Increasing [KCl]o (from 5 to 70 mM) led to concentration-dependent swelling in chicken retinas.

Effect of the application of acid treated biosolids on marigold (Tagetes erecta) development.

The use of biosolids for land restoration and crop production is a potential solution to improve food production worldwide. However, the microbial content usually restricts its application in crops that are consumed uncooked. An alternative practice is their use in floriculture.

Sustainable sludge management in developing countries.

Worldwide, unsanitary conditions are responsible for more than three million deaths annually. One of the reasons is the low level of sanitation in developing countries. Particularly, sludge from these regions has a high parasite concentration and low heavy metal content even though the available information is limited.

Characterization and evaluation of potential reuse options for wastewater sludge and combined sewer system sediments in Mexico.

Combined sewer systems generate sediments that have characteristics similar to those of primary sludge. Mexico City has such a system composed of a network of pipes, regulation structures (dams, basins) and open channels. The annual generation of sediments is estimated at 2.

In the cradle of heredity; French physicians and l'hérédité naturelle in the early 19th century.

This paper argues that our modern concept of biological heredity was first clearly introduced in a theoretical and practical setting by the generation of French physicians that were active between 1810 and 1830. It describes how from a traditional focus on hereditary transmission of disease, influential French medical men like Esquirol, Fodéré, Piorry, Lévy, moved towards considering heredity a central concept for the conception of the human bodily frame, and its set of physical and moral dispositions. The notion of heredity as a natural force, with a wide ranging capabilities of transmitting differentially both fundamental and accidental characters was generalized by that generation of physicians with the help of contemporary naturalists and physiologists.

Influence of the origin of the inoculum and the acclimation strategy on the degradation of 4-chlorophenol.

The influence of the inoculum source and the acclimation strategy on the 4-chlorophenol (4CP) degradation in a sequencing batch reactor (SBR) was studied. Three different sources of inocula were obtained from the aeration tank of domestic, municipal and industrial wastewater treatment plants. The acclimation was performed using two strategies, the first one fixing the reaction time, independent of the removal efficiency (fixed time) and the second one fixing a removal efficiency of 90% as 4CP (variable time).

Epidermal growth factor receptor is activated by hyposmolarity and is an early signal modulating osmolyte efflux pathways in Swiss 3T3 fibroblasts.

Exposure of cultured Swiss 3T3 fibroblasts to 35% hyposmotic solution activated epidermal growth factor receptor (EGFR) phosphorylation to a greater extent than the ligand, EGF. Concanavalin A (Con A) and wheat-germ agglutinin (WGA) had the same effect. EGFR phosphorylation seems to be involved in the transduction signalling for hyposmotically induced taurine release, as suggested by the latter's reduction when EGFR phosphorylation was blocked by 50 microM AG213 or AG112 and, conversely, its potentiation by EGF (200 ng/ml).

Determination of the oxidative stability of olive oil, using focused-microwave energy to accelerate the oxidation process.

A new method is proposed for rapid monitoring of the oxidative stability of virgin olive oil. Samples were irradiated with microwave energy to accelerate the oxidation process and photometric monitoring was performed at 232 and 270 nm. Conditions such as microwave irradiation power, number of irradiation cycles, and irradiation time were optimized by means of multivariate screening that showed that irradiation power is the most significant condition in the oil oxidation process.

Pharmaceutical wastewater treatment using an anaerobic/aerobic sequencing batch biofilter.

The performance of a sequencing batch biofilter integrating anaerobic/aerobic conditions in one tank to treat a pharmaceutical wastewater effluent was studied. A pilot reactor, packed with a porous volcanic stone (puzzolane) was used in the study. The reactor operated as a sequencing batch biofilter, SBB, with reaction times varying for the anaerobic stage from 8 to 24 h and for the aerobic one from 4 to 12 h.

Degradation of p-nitrophenol in a batch biofilter under sequential anaerobic/aerobic environments.

A combined process anaerobic/aerobic in a single reactor was studied, P-nitrophenol (PNP) was used as the model compound. During the anaerobic stage the target compound is modified in such a way that the intermediate product is more readily biodegradable by the aerobic phase. A pilot biofilter was used for the experiment.

Hypoglycemic effect of Equisetum myriochaetum aerial parts on streptozotocin diabetic rats.

The hypoglycemic effect of water as well as butanolic extracts prepared from aerial parts of Equisetum myriochaetum (Equisetaceae) was examined in streptozotocin induced diabetic rats. A single oral administration of the water extract (WE) at doses of 7 and 13 mg/kg and of the butanol extract (BE) at doses of 8 and 16 mg/kg significantly (P<0.001) lowered the plasma glucose levels in diabetic rats after three hours of the administration.

MMPI-2 with Mexican psychiatric inpatients: basic and content scales.

This paper presents the results of a study of the Mexican Spanish version of the MMPI-2 with a clinical sample of 233 patients who were diagnosed as having psychological disturbances or personality disorders, according to DSM-III R criteria. Inpatient scores were obtained from four psychiatric hospitals, located in Mexico City. The scores of the patients were compared with those of Mexican college students, which is the largest Mexican normative sample collected to date, consisting of 813 men and 1,137 women.

Sources of abnormal EEG activity in the presence of brain lesions.

In routine clinical EEG, a common origin is assumed for delta and theta rhythms produced by brain lesions. In previous papers, we have provided some experimental support, based on High Resolution qEEG and dipole fitting in the frequency domain, for the hypothesis that delta and theta spectral power have independent origins related to lesion and edema respectively. This paper describes the results obtained with Frequency Domain VARETA (FD-VARETA) in a group of 13 patients with cortical space-occupying lesions, in order to: 1) Test the accuracy of FD-VARETA for the localization of brain lesions, and 2) To provide further support for the independent origin of delta and theta components.

Flight and echlocation in the ecology and evolution of bats.

Flight and echolocation are key characters distinguishing most bats from other mammals.The number of ecolological niches for bats is limited by the concurent constraints of the mammalian physiology and reproductive system and the high cost of flight and echolocation. The recent discovery of a biomechanical coupling between echolocation and flight highlights the need to incorporate both chracters as parts of a single adaptive complex in future research on the ecology and evolution of bats.