High-resolution manometry findings in patients with achalasia and massive dilated megaesophagus.

Achalasia may present in a non-advanced or an advanced (end stage) stage based on the degree of esophageal dilatation. Manometric parameters and esophageal caliber may be prognostic for the outcome of treatment. The correlation between manometry and disease stage has not been yet fully studied. This study aims to describe high-resolution manometry findings in patients with achalasia and massive dilated megaesophagus. Eighteen patients (mean age 61 years, 55% females) with achalasia and massive dilated megaesophagus, as defined by a maximum esophageal dilatation >10 cm at the barium esophagram, were studied. Achalasia was considered secondary to Chagas' disease in 14 (78%) of the patients and idiopathic in the remaining. All patients underwent high-resolution manometry. Upper esophageal sphincter was hypotonic and had impaired relaxation in the majority of patients. Aperistalsis was seen in all patients with an equal distribution of Chicago type I and type II. No type III was noticed. Lower esophageal sphincter did not have a characteristic manometric pattern. In 50% of the cases, the manometry catheter was not able to reach the stomach. Our results did not show a manometric pattern in patients with achalasia and massive dilated esophagus.

Differentiation of typical and atypical enteropathogenic Escherichia coli using colony immunoblot for detection of bundle-forming pilus expression.

AIMS: The aim of study was to develop a colony immunoblot assay to differentiate typical from atypical enteropathogenic Escherichia coli (EPEC) by detection of bundle-forming pilus (BFP) expression. METHODS AND RESULTS: Anti-BFP antiserum was raised in rabbits and its reactivity was confirmed by immunoelectron microscopy and by immunoblotting recognizing bundlin, the major pilus repeating subunit. The bacterial isolates tested in the colony immunoblot assay were grown in different media. Proteins from bacterial isolates were transferred to nitrocellulose membrane after treatment with phosphate buffer containing Triton X-100, EDTA and sodium chloride salts. When 24 typical EPEC and 96 isolates including, 72 atypical EPEC, 13 Gram-negative type IV-expressing strains and 11 enterobacteriaceae were cultivated in Dulbecco's Modified Eagle's Medium agar containing fetal bovine serum or in blood agar in the presence of CaCl(2) , they showed a positivity of 92 and 83%, and specificity of 96 and 97%, respectively. CONCLUSION: The assay enables reliable identification of BFP-expressing isolates and contributes to the differentiation of typical and atypical EPEC. SIGNIFICANCE AND IMPACT OF THE STUDY: The colony immunoblot for BFP detection developed in this study combines the simplicity of an immunoserological assay with the high efficiency of testing a large number of EPEC colonies.

Identification of enteropathogenic and enterohaemorrhagic Escherichia coli strains by immunoserological detection of intimin.

AIMS: To evaluate the sensitivity and specificity of polyclonal and monoclonal antibodies (Mabs) against intimin in the detection of enteropathogenic and enterohaemorrhagic Escherichia coli isolates using immunoblotting. METHODS AND RESULTS: Polyclonal and Mabs against the intimin-conserved region were raised, and their reactivities were compared in enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC) isolates using immunoblotting analysis. In comparison with rat antiserum, rabbit anti-intimin IgG-enriched fraction had a stronger recognition pattern to a wide spectrum of intimin types in different EPEC and EHEC serotypes. On the other hand, murine monoclonal IgG2b specific to intimin, with dissociation constant of 1.3x10(-8) mol l(-1), failed in the detection of some of these isolates. CONCLUSION: All employed antibodies showed 100% specificity, not reacting with any of the eae-negative isolates. The sensitivity range was according to the employed antisera, and 97% for rabbit anti-intimin IgG-enriched fraction, followed by 92% and 78% sensitivity with rat antisera and Mab. SIGNIFICANCE AND IMPACT OF THE STUDY: The rabbit anti-intimin IgG-enriched fraction in immunoblotting analysis is a useful tool for EPEC and EHEC diagnoses.

A comparative neutron activation analysis study of common generic manipulated and reference medicines commercialized in Brazil.

In this work, a comparative study of neutron activation analysis (NAA) was performed by the nuclear institutes: CDTN/CNEN-Brazil, CCHEN-Chile and the SCK.CEN-Belgium aiming to investigate some generic, manipulated and reference medicines largely commercialized in Brazil. Some impurities such as: As, Ba, Br, Ce, Co, Cr, Eu, Fe, Hf, Sb, Sc, Sm, Ti and Zn were found, and the heterogeneity of the samples pointed out the lack of an efficient public system of quality control.

Calibrated Gastrojejunostomy in Gastric Bypass: It Is a Myth.

BACKGROUND: Many surgeons prefer a narrow gastrojejunostomy in gastric bypass believing that this provides greater weight loss. The question is whether the anastomosis remains at its initial diameter, whether it narrows or widens over time. This study tests the hypothesis that the initial diameter of the anastomosis varies over time. MATERIALS AND METHODS: One hundred obese had undergone surgery. Group A with anastomosis 1.5 cm wide and group B with anastomosis 3 cm wide. One-year follow-up was done for 83 patients. The size of the anastomosis diameter was evaluated using a balloon for cardia dilation. RESULTS: Comparing the results of surgery with the values presented 1 year after the procedure, (i) BMI decreased from 43.3 ± 6.6 to 28.7 ± 7.0 kg/m2 for group A and 44.6 ± 5.9 to 29.1 ± 6.3 kg/m2 for group B, (ii) the total weight loss was 30.6 ± 4.7% for group A and 31.9 ± 5.2% for group B, and (iii) the initial 1.5-cm anastomosis in group A measured 2.3 ± 1.0 cm while the initial 3-cm anastomosis in group B measured 2.7 ± 1.0 cm 1 year after surgery. No statistically significant difference was found for any of the variables evaluated before and after the surgical procedure. CONCLUSION: Calibrated anastomosis has no utility in increasing weight loss in gastric bypass.

Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita).

We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools based on principles of statistical generality are nowadays a common practice for describing these phenomena, but, in general, they are more capable of generating clear diagnosis rather than granting valuable modelling. For this reason, in our approach, we detect the principal temporal structures on the bases of different correlation measures, and from these results we build an ad-hoc minimalist autoregressive model that incorporates the main drivers of the dynamics. Surprisingly our model is capable of reproducing very well the time patterns of the empirical series and, for the first time, clearly outlines the importance of the time of attaining sexual maturity as a central temporal scale for the dynamics of this species. In fact, an important advantage of this analysis scheme is that all the model parameters are directly biologically interpretable and potentially measurable, allowing a consistency check between model outputs and independent measurements.

Marketing strategy: an essential component of business development for academic health centers.

BACKGROUND: Historically, academic health centers (AHCs) have detached themselves from commercialism and entrepreneurism, viewing these activities as being inconsistent with many of their core academic values. Word-of-mouth promotion was their primary, if not sole, marketing strategy. Less emphasis was placed on preparing, pricing, distributing, and promoting these services to targeted audiences. Understanding customers' needs was not a top priority. METHODS: The marketing strategies and tools currently being developed and utilized by AHCs were reviewed. RESULTS: In an effort to attract customers and win contracts, AHCs are aggressively marketing themselves by designing new services, promoting those services much more intensely, restructuring the entire distribution system that delivers those services, and crafting pricing strategies that build in flexibility. With growing frequency, these marketing tactics are part and parcel of a carefully crafted data-driven strategic plan designed to meet the business-development goals of the institution. CONCLUSIONS: In order to carry out their missions, AHCs have recognized that they can no longer rest on their "ivory tower" laurels. They must learn how to market themselves in a market economy.

Temporal lobectomy in early childhood: the need for long-term follow-up.

We retrospectively identified 15 children ages 12 years and under with anticonvulsant resistant epilepsy who underwent a temporal lobectomy at Children's Hospital, Boston, between 1978 and 1993. Our aim was to study the long-term seizure outcome. Data pertaining to preoperative evaluation, electroencephalography (EEG), neuroimaging, surgery, seizure outcome, and postoperative complications were reviewed. Only patients followed for more than 12 months were included. The average duration of follow-up was 57 months. At the last visit, 47% (7 of 15) of the children were seizure free or only had auras: another 33% (5 of 15) had > 90% reduction in seizure frequency. Three patients had < 90% seizure reduction. Four cases were initially seizure free but had subsequent recurrence between 11 and 28 months after the epilepsy surgery. Factors associated with a good outcome include exclusively focal EEG discharges or an imaging suggestive of a low-grade tumor; factors associated with a poor outcome include generalized EEG discharges and a normal magnetic resonance image. Temporal lobectomy is useful in the treatment of early childhood drug-resistant partial epilepsy, but long-term follow-up is necessary as late seizure recurrence may occur up to 28 months after surgery.

Effect of beta-myrcene on pentobarbital sleeping time.

Evidence that beta-myrcene (MYR) interferes with the metabolic activation of premutagens has been provided by in vitro studies. In order to determine whether MYR also interferes with the in vivo metabolism of xenobiotics, thereby modifying pharmacological responses to drugs, we investigated the effects of this monoterpene on pentobarbital (PT) sleeping time in rats. Two experiments were carried out. In the first, a single dose of MYR (0.25, 0.5 or 1.0 g/kg po) was given 1 h before PT (40 mg/kg ip). No effect was observed with the two lowest doses, but the highest MYR dose given 1 h before PT increased the PT-induced sleeping time (131 +/- 15 min vs 64 +/- 15 min for controls, mean +/- SD). In the second experiment, male rats were treated with MYR (1.0 g/kg po once a day) for 14 days and injected with PT (40 mg/kg ip) 24 h after the last dose of MYR. Repeated treatment with MYR markedly reduced PT sleeping time compared to the vehicle-treated control group (21 +/- 13 min vs 35 +/- 19 min for controls, mean +/- SD). These results indicate that MYR interferes with the in vivo barbiturate metabolism and support the view that MYR induces the phenobarbital-inducible cytochrome P-450 (P-450 2B subfamily) enzymes in the rat.

Comparison of five methods for the determination of lethal dose in acute toxicity studies.

The aim of the present study was to compare the reliability of LD50 determination using the traditional Litchfield and Wilcoxon method with that obtained by four alternative tests requiring smaller numbers of animals, for the purpose of classifying chemicals according to their acute toxicity. Acute lethal dose determinations were carried out in mice for oral and intraperitoneal administration of hexachlorophene, lidocaine, methanol, phenobarbital and physostigmine. The Molinengo method proved not to be as reliable as suggested by its author. Determination of LD50 using the Thompson and Weil method or, alternatively, the maximal non-lethal dose and the approximate lethal dose permitted the classification of the chemicals in essentially the same order. The approximate lethal dose method, in particular, seems to be a very suitable alternative method to the classical LD50 test since it requires only about 6 animals, provides enough information to order chemicals according to their toxicities, and provides useful information for planning subsequent repeated-dose studies.

Neurobehavioral study of the effect of beta-myrcene on rodents.

Tea prepared from lemongrass (Cymbopogon citratus) is used for its supposed anxiolytic, hypnotic and analgesic properties in Brazilian folk medicine. beta-Myrcene, a major constituent of lemongrass, produces analgesia in rodents but there is some controversy about whether this action is central or peripheral or both. Rats and mice received beta-myrcene, 1 g/kg po in corn oil, or corn oil alone 1 h before being evaluated for a series of responses which included exploratory and emotional behavior, anxiolytic activity in a plus maze and inhibition of conditioned avoidance. No evidence was demonstrable for an effect of beta-myrcene on any of these behaviors. Similarly, beta-myrcene had no protective effect on pentylenetetrazol (PTZ)-induced seizures in mice. These data suggest that beta-myrcene has no benzodiazepine-like anxiolytic activity and that an activity on the central nervous system (antidepressive or antipsychotic) is unlikely. Despite the negative results of this study, folk use of lemongrass tea may still be justified by its analgesic properties.

[Coronary transluminal angioplasty in octogenarians]. / Angioplastia transluminal coronária em octogenários.

PURPOSE: To evaluate the immediate and long term results of percutaneous transluminal coronary balloon angioplasty (PTCA) in patients over 80 years old. METHODS: From 1/1/89 to 6/31/95, 97 patients with 80 years of age or older were submitted to PTCA and were divided into three groups: group A (GrA)-30 patients with stable angina, mean age of 82.5 years, 24 (80%) men; group B(GrB)-40 patients with unstable angina, mean age 81.2 years, 31 (77.5%) men; group C (GrC)-27 patients with myocardial infarction (MI), mean age of 82 years, 16 (59.2%) men. RESULTS: Early outcome-general success rate of 84.5% and mortality rate of 5.1%. The success and mortality rate were in GrA 83.3% and 3.3%, in GrB 85% and 5% and in GrC 85.2% and 7.4%, respectively. Late outcome-the number and percentage of patients with late follow-up and the clinic-angiographic and angiographic restenosis rates were for GrA 19(76%), 52.9%, 75%; GrB 30(88.2%), 30.8%, 61.5% and GrC 12(52.2%), 66.6%, 85.7%, respectively. CONCLUSION: PTCA can be considered an important revascularization alternative in octogenarian patients because of high early success rate, low mortality and acceptable long-term outcome.

k0-INAA quality assessment by analysis of soil reference material GBW07401 using the comparator and neutron flux monitor approaches.

It is possible to apply the k(0)-method using a simplified equation for concentration calculations using Excel spreadsheet, using comparators without making corrections. The objective of this study was to confirm that the k(0)-standardization method is more efficient and accurate than this "k(0)-comparator" procedure, applying suitable software that takes into account several corrections. The reference material GBW07401 soil was analyzed in this study. Relative Bias and u-score tests were used in order to evaluate the overall results.

Adherence and invasion of Bacteroidales isolated from the human intestinal tract.

Members of the genera Bacteroides and Parabacteroides are important constituents of both human and animal intestinal microbiota, and are significant facultative pathogens. In this study, the ability of Bacteroides spp. and Parabacteroides distasonis isolated from both diarrhoeal and normal stools (n = 114) to adhere to and invade HEp-2 cells was evaluated. The presence of putative virulence factors such as capsule and fimbriae was also investigated. Adherence to HEp-2 cells was observed in 75.4% of the strains, which displayed non-localized clusters. Invasion was observed in 37.5% and 26% of the strains isolated from diarrhoeal and non-diarrhoeal stools, respectively. All strains displayed a capsule, whereas none of them showed fimbriae-like structures. This is the first report of the ability of Bacteroides spp. and P. distasonis to adhere to and invade cultured HEp-2 epithelial cells.

Intracellular crowding defines the mode and sequence of substrate uptake by Escherichia coli and constrains its metabolic activity.

The influence of the high intracellular concentration of macromolecules on cell physiology is increasingly appreciated, but its impact on system-level cellular functions remains poorly quantified. To assess its potential effect, here we develop a flux balance model of Escherichia coli cell metabolism that takes into account a systems-level constraint for the concentration of enzymes catalyzing the various metabolic reactions in the crowded cytoplasm. We demonstrate that the model's predictions for the relative maximum growth rate of wild-type and mutant E. coli cells in single substrate-limited media, and the sequence and mode of substrate uptake and utilization from a complex medium are in good agreement with subsequent experimental observations. These results suggest that molecular crowding represents a bound on the achievable functional states of a metabolic network, and they indicate that models incorporating this constraint can systematically identify alterations in cellular metabolism activated in response to environmental change.

Directed rigidity and bootstrap percolation in 1+1 dimensions.

We study directed rigidity percolation (equivalent to directed bootstrap percolation) on three different lattices: square, triangular, and augmented triangular. The first two of these display a first-order transition at p=1, while the augmented triangular lattice shows a continuous transition at a nontrivial p(c). On the augmented triangular lattice we find, by extensive numerical simulation, that the the directed rigidity percolation transition belongs to the same universality class as the directed percolation. The same conclusion is reached by studying its surface critical behavior, i.e., the spreading of rigidity from finite clusters close to a nonrigid wall. Near the discontinuous transition at p=1 on the triangular lattice, we are able to calculate the finite-size behavior of the density of rigid sites analytically. Our results are confirmed by numerical simulation.

Lamotrigine-induced tic disorder: report of five pediatric cases.

PURPOSE: To describe the clinical spectrum of lamotrigine (LTG)-induced tics (an uncommon side effect) in children. METHODS: Retrospective analysis of patients from our hospital-based practice who developed tics while on LTG. Data obtained from medical records, interviews with parents, video-EEGs, and homemade videotapes. RESULTS: Three males and two females (range, 2.5-12 years; mean, 6.9 years) developed a movement disorder within the first 10 months of therapy (maintenance doses, 4-17 mg/kg/day). Four patients exhibited simple motor tics; one patient experienced mostly vocal (i.e., gasping sounds) tics. Laryngoscopic evaluation of one 2.5-year-old with repetitive gasping sounds was normal. In three cases, tics resolved completely within 1 month of drug cessation; tics recurred in two of these patients after reintroduction of LTG. A fourth patient experienced gradual improvement after stopping LTG over 4 months; the fifth patient's simple motor tics improved spontaneously with a reduction in medication. None of the patients had clinical features of a neurodegenerative disorder, and none met diagnostic criteria for Tourette syndrome. Two patients, however, had a diagnosis of acquired epileptic aphasia syndrome, and one patient had nonprogressive expressive and receptive language dysfunction. A fourth patient had global static encephalopathy, and the fifth patient had only attentional problems. In all patients, tics were not associated with ictal EEG changes. CONCLUSIONS: LTG may infrequently induce simple motor tics, vocal tics, or both. Patients with severe language dysfunction may be particularly susceptible to this uncommon side effect. Further studies are necessary to clarify the population at risk.

Expression of muscle-specific myosin heavy chain and myosin light chain 1 in the electric tissue of Electrophorus electricus (L.) in comparison with other vertebrate species.

Myosin light and heavy chains from skeletal and cardiac muscles and from the electric organ of Electrophorus electricus (L.) were characterised using biochemical and immunological methods, and compared with myosin extracted from avian, reptilian, and mammalian skeletal and cardiac muscles. The results indicate that the electric tissue has a myosin light chain 1 (LC1) and a muscle-specific myosin heavy chain. We also show that monoclonal antibody F109-12A8 (against LC1 and LC2) recognizes LC1 of myosin from human skeletal and cardiac muscles as well as those of rabbit, lizard, chick, and electric eel. However, only cardiac muscles from humans and rabbits have LC2, which is recognized by antibody F109-16F4. The data presented confirm the muscle origin of the electric tissue of E. electricus. This electric tissue has a profile of LC1 protein expression that resembles the myosin from cardiac muscle of the eel more than that from eel skeletal muscle. This work raises an interesting question about the ontogenesis and differentiation of the electric tissue of E. electricus.

Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye.

Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not preclude its use as a molluscicide, special precautions are recommended for handling and application of the product and the hazard of skin tumor-promoting potential should be carefully investigated before its use for schistosomiasis vector control.

Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye

Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not proclude its use as a molluscicide, special precautions are recommended for hanbdling and application of the product and the hazard of skin tumor-promoting potencial should be carefully investigated before its use for schistosomiasis vector control.