Benzofurans as Acetylcholinesterase Inhibitors for Treating Alzheimer's Disease: Synthesis, in†vitro Testing, and in†silico Analysis.

Alzheimer's disease (AD) is a neurodegenerative disorder and the leading cause of dementia worldwide. It is characterized by a progressive decline in cholinergic neurotransmission. During the development of AD, acetylcholinesterase (AChE) binds to ß-amyloid peptides to form amyloid fibrils, which aggregate into plaque deposits. Meanwhile, tau proteins are hyperphosphorylated, forming neurofibrillary tangles (NFTs) that aggregate into inclusions. These complexes are cytotoxic for the brain, causing impairment of memory, attention, and cognition. AChE inhibitors are the main treatment for AD, but their effect is only palliative. This study aimed to design and synthesize novel benzofuran derivatives and evaluate their inhibition of AChE in vitro and in silico. Results: The seven synthesized benzofuran derivatives inhibited AChE in vitro. Benzofurans hydroxy ester 4, amino ester 5, and amido ester (±)-7 had the lowest inhibition constant (Ki) values and displayed good affinity for EeAChE in molecular docking. Six derivatives showed competitive inhibition, while the best compound (5: Ki=36.53 µM) exhibited uncompetitive inhibition. The amino, hydroxyl, amide, and ester groups of the ligands favored interaction with the enzyme by hydrogen bonds. Conclusion: Three benzofurans were promising AChE inhibitors with excellent Ki values. In future research on their their application to AD, 5 will be considered as the base structure.

Interactions between the principal risk factors for reduction of the eGFR in unvaccinated COVID­19 survivors: Normal pre-COVID­19 eGFR, not having diabetes and being hospitalized.

There are contradictory results regarding changes in estimated glomerular filtration rate (eGFR) in coronavirus disease 2019 (COVID-19) survivors. An analysis of eGFR changes and clinical characteristics associated with those changes was conducted among COVID-19 survivors. eGFR values were compared at different time points (before and 4-, 8- and 12-months after COVID-19 infection). A multivariate generalized linear mixed model (GENLINMIXED procedure) with a binary logistic regression link was used to determine factors associated with eGFR reduction of ≥10 ml/min/1.73 m2. Being hospitalized (RR=2.90, 95% CI=1.10-7.68, P=0.032), treated with Ivermectin (RR=14.02, 95% CI=4.11-47.80, P<0.001) or anticoagulants (RR=6.51, 95% CI=2.69-15.73, P<0.001) are risk factors for a reduced eGFR. Having a low eGFR (<90 ml/min/1.73 m2) before COVID-19 infection, having B-positive blood type, diabetes, taking vitamin C during the acute phase of COVID-19 or suffering from chronic COVID-19 symptoms, were identified as protective factors. Analysis involving a two-way interaction (A x B, where A and B are factors) demonstrated that the combination of patients with a normal eGFR value before COVID-19 infection without diabetes (RR=58.60, 95% CI=11.62-295.38, P<0.001), or a normal eGFR value with being hospitalized for COVID-19 (RR=38.07, 95% CI=8.68-167.00, P<0.001), increased the probability of a reduced eGFR. The changes in eGFR in COVID-19 survivors varied depending on patient characteristics. Furthermore, the principal risk factors for post-COVID-19 eGFR reduction were analyzed in separate models.

Comorbidities and clinical symptoms can modify myocardial function: a cross-sectional study with PET/CT / Comorbilidades y síntomas clínicos que pueden modificar la función miocárdica: estudio transversal con PET/TC

Abstract Objective: Associating comorbidities and cardiac symptoms that alter myocardial mechanical function could help clinicians to correctly identify at-risk population. Methods: We conducted a functional open population cross-sectional study of patients referred to a positron emission tomography/computed tomography unit in Mexico City for evaluation of myocardial function, perfusion, and coronary circulation. Ischemia was defined as a sum difference score ≥ 2. Association between comorbidities and cardiac symptoms was tested using logistic regression models and trend analysis. We performed an interaction analysis to evaluate the addition of any accompanying symptoms to comorbid conditions on impairment of myocardial function. Results: One thousand two hundred and seventy-three patients were enrolled, 66.1% male, with a mean age of 62.4 (± 12.7) years, 360 (28.7%) with ischemia, 925 (72.7%) with at least one comorbidity, and 676 (53.1%) had at least one associated cardiac symptom. Patients without ischemia, type 2 diabetes, arterial hypertension, and adverse cardiac symptoms were associated with adverse mechanical, perfusion, and coronary flow parameters. We observed a trend of a cumulative number of comorbidities and cardiac symptoms with increased ischemia and decreased coronary flow. Only in decreased left ventricular ejection fraction, we demonstrated an interaction effect between increased comorbidities and adverse symptoms. Conclusion: The high burden of comorbidities and symptoms in our population alters myocardial function regardless of the level of ischemia.

Resumen Objetivo: La asociación de comorbilidades y síntomas cardíacos que alteran la función miocárdica podría ayudar a los médicos a identificar correctamente a poblaciones de riesgo. Métodos: Se realizó un estudio transversal en población abierta de pacientes referidos a una unidad de PET/CT en la Ciudad de México para evaluación de la función miocárdica, perfusión y circulación coronaria. La isquemia se definió como una suma de diferencia de puntuación (SDS) ≥ 2. La asociación entre las comorbilidades y los síntomas cardíacos se fundamentó mediante modelos de regresión logística y análisis de tendencias. Realizamos un análisis de interacción para evaluar la adición de cualquier síntoma acompañante a condiciones comórbidas en el deterioro de la función miocárdica. Resultados: Se incluyeron 1.273 pacientes, 66,1% del sexo masculino, con una edad media de 62,4 (± 12.7) años, 360 (28,7%) con isquemia, 925 (72,7%) con al menos una comorbilidad y 676 (53,1%) con al menos una menos un síntoma cardíaco asociado. En pacientes sin isquemia, la diabetes mellitus tipo 2, la hipertensión arterial y los síntomas cardíacos adversos se asociaron con parámetros mecánicos, de perfusión y de flujo coronario adversos. Se observó una tendencia con el número acumulado de comorbilidades y síntomas cardíacos con aumento de la isquemia y disminución del flujo coronario. Solo en la disminución de la FEVI se demostró un efecto de interacción entre el aumento de las comorbilidades y los síntomas adversos. Conclusión: La alta carga de comorbilidades y síntomas en nuestra población altera la función miocárdica independientemente del nivel de isquemia.

Comorbidities and cardiac symptoms can modify myocardial function regardless of ischemia: a cross-sectional study with PET/CT.

Objective: Associating comorbidities and cardiac symptoms that alter myocardial mechanical function could help clinicians to correctly identify at-risk population. Methods: We conducted a functional open population cross-sectional study of patients referred to a positron emission computed tomography/computed tomography unit in Mexico City for evaluation of myocardial function, perfusion, and coronary circulation. Ischemia was defined as a sum difference score (SDS) > 2. Association between comorbidities and cardiac symptoms was tested using logistic regression models and trend analysis. We performed an interaction analysis to evaluate the addition of any accompanying symptoms to comorbid conditions on impairment of myocardial function. Results: One thousand two hundred and seventy-three patients were enrolled, 66.1% male, with a mean age of 62.4 (± 12.7) years, 360 (28.7%) with ischemia, 925 (72.7%) with at least one comorbidity, and 676 (53.1%) had at least one associated cardiac symptom. Patients without ischemia, type 2 diabetes, arterial hypertension, and adverse cardiac symptoms were associated with adverse function, perfusion, and coronary flow parameters. We observed a trend of a cumulative number of comorbidities and cardiac symptoms with increased ischemia and decreased coronary flow. Only in decreased LVEF, we demonstrated an interaction effect between increased comorbidities and adverse symptoms. Conclusions: The high burden of comorbidities and symptoms in our population alter myocardial function regardless of the level of ischemia.

Recovery of Naringin-Rich Flavonoid Extracts from Agroresidues with Anxiolytic- and Antidepressant-like Effects in Mice.

Citrus paradisi species belong to the Rutaceae family, and it is commonly known as grapefruit. Grapefruit consumption involves a large amount of waste that goes to landfills and produces significant pollution affecting the human health. To examine this phenomenon, we designed an efficient chemical method that recovers naringin-rich flavonoid extracts from the fresh waste of grapefruits, by using the solvent impregnation resin method (SIR) with XAD-4 amberlite and either methanol or water as elution systems. Additionally, we focused on evaluating these extracts' anxiolytic- and antidepressant-like effects in behavioral predictive paradigms in mice. According to direct Principal Component Analysis (PCA) by NMR, and Direct Injection Electrospray Ionization-Mass Spectrometry (DIESI-MS), methanol extracts obtained after resin treatment were free of coumarin compounds and evinced had a high content of naringin. Poncirin, phenylalanine, chrysin 5,7-dimethyl ether, 5,7-dimethoxy-4'-hydroxyflavanone, 2,3-dihydro-2-(4-hydroxyphenyl)-5,6,7,8-tetramethoxy-4H-1-benzopyran-4-one, tetrahydrocurcumin, corchoionoside C, 6'-coumaroyl-1'-O-[2-(3,4-dihydroxyphenyl) ethyl]-ß-D-glucopyranoside were also detected. Naringin-rich methanol extract caused a clear anxiolytic-like effect in the Elevated Plus Maze (EPM) and the Hole-Board (HBT) Tests, increasing oral doses of this extract did not produce a sedative effect. A single oral dose caused an antidepressant-like effect in the Tail Suspension Test (TST), while repeated administrations of the methanol extract elicited a robust antidepressant effect in the Forced Swimming Test (FST) in mice. Our evidence highlights the importance of bioprospecting studies of organic waste with therapeutic potentials, such as anxiety and depression disorders.

Determining global trends in syngas fermentation research through a bibliometric analysis.

Syngas fermentation, in which microorganisms convert H2, CO, and CO2 to acids and alcohols, is a promising alternative for carbon cycling and valorization. The intellectual landscape of the topic was characterized through a bibliometric analysis using a search query (SQ) that included all relevant documents on syngas fermentation available through the Web of Science database up to December 31st, 2021. The SQ was validated with a preliminary analysis in bibliometrix and a review of titles and abstracts of all sources. Although syngas fermentation began in the early 1980s, it grew rapidly beginning in 2008, with 92.5% of total publications and 87.3% of total citations from 2008 to 2021. The field has been steadily moving from fundamentals towards applications, suggesting that the field is maturing scientifically. The greatest number of publications and citations are from the USA, and researchers in China, Germany, and Spain also are highly active. Although collaborations have increased in the past few years, author-cluster analysis shows specialized research domains with little collaboration between groups. Based on topic trends, the main challenges to be address are related to mass-transfer limitations, and researchers are starting to explore mixed cultures, genetic engineering, microbial chain elongation, and biorefineries.

In silico and in vivo neuropharmacological evaluation of two γ-amino acid isomers derived from 2,3-disubstituted benzofurans, as ligands of GluN1-GluN2A NMDA receptor.

The GABAergic and glutamatergic neurotransmission systems are involved in seizures and other disorders of the central nervous system (CNS). Benzofuran derivatives often serve as the core in drugs used to treat such neurological disorders. The aim of this study was to synthesize new γ-amino acids structurally related to GABA and derived from 2,3-disubstituted benzofurans, analyze in silico their potential toxicity, ADME properties, and affinity for the GluN1-GluN2A NMDA receptor, and evaluate their potential activity and neuronal mechanisms in a murine model of pentylenetetrazol (PTZ)- and 4-aminopyridine (4-AP)-induced seizures. The in silico analysis evidenced a low risk of toxicity for the test compounds as well as the probability that they can cross the blood-brain barrier (BBB) to reach their targets in the CNS. According to docking simulations, these compounds bind at the active site of the NMDA glutamate receptor with high affinity. The in vivo assays demonstrated that 4 protects against 4-AP-induced seizure episodes, suggesting negative allosteric modulation (NAMs) at the glutamatergic NMDA receptor. Contrarily, 3 (the regioisomer of 4) and its racemic derivatives (cis-2,3-dihydrobenzofurans) were previously described to exacerbate such episodes, pointing to their positive allosteric modulation (PAMs) of the same receptor.

Reparación toracoscópica de la atresia esofágica: implicaciones en el pronóstico del paciente / Thoracoscopic Repair of Esophageal Atresia: Implications in the prognosis of the patient

La reparación por toracoscopia de la atresia del esófago se ha constituido paulatinamente en la mejor alternativa terapéutica de los pacientes con esta entidad. Se analizaron 21 pacientes con diagnóstico de atresia esofágica operados por toracoscopia de Noviembre del 2017 a Agosto del 2020. La edad en que se efectuó la cirugía fue de 1 a 15 días de vida, promedio de 4.5. El procedimiento efectuado fue: sección y ligadura de la fistula con anastomosis termino terminal. El tiempo de cirugía fue de 90 a 240 minutos con una media de 158.5 minutos. Las complicaciones postoperatorias fueron: 02 pacientes dehiscencia parcial de la anastomosis, 05 pacientes estrechez de la anastomosis y 01 paciente divertículo traqueal. Hubo 03 pacientes que fallecieron. La reparación toracoscópica de la atresia de esófago es una opción terapéutica eficiente, con una tasa de complicaciones aceptable y una menor mortalidad. (AU)

Thoracoscopic repair of esophageal atresia has gradually become the best therapeutic alternative for patients with this entity. 21 patients with a diagnosis of esophageal atresia operated by thoracoscopy from November 2017 to August 2020 were analyzed. The age at which the surgery was performed was 1 to 15 days old, average 4.5. The procedure was: section and ligation of the fistula with end-to-end anastomosis. The surgery time was 90 to 240 minutes with a mean of 158.5 minutes. Postoperative complications were: 02 patients partial dehiscence of the anastomosis, 05 patients narrowing the anastomosis and 01 patient tracheal diverticulum. There were 03 patients who died. Thoracoscopic repair of esophageal atresia is an efficient therapeutic option, with an acceptable complication rate and lower mortality. (AU)

SMP Production in an Anaerobic Submerged Membrane Bioreactor (AnMBR) at Different Organic Loading Rates.

Anaerobic membrane bioreactors (AnMBRs) have demonstrated an excellent capability to treat domestic wastewater. However, biofouling reduces membrane permeability, increasing operational costs and overall energy demand. Soluble microbial products (SMPs) that build up on the membrane surface play a significant role in the biofouling. In this study, the production of SMPs in a 32 L submerged AnMBR operated at three different organic loads (3.0, 4.1 and 1.2 kg chemical oxygen demand (COD)/m3d for phases 1, 2 and 3, respectively) during long-term operation of the reactor (144, 83 and 94 days) were evaluated. The samples were taken from both the permeate and the sludge at three different heights (0.14, 0.44 and 0.75 m). Higher production of SMPs was obtained in phase 2, which was proportional to the membrane fouling. There were no statistically significant differences (p > 0.05) in the SMPs extracted from sludge at different heights among the three phases. In the permeate of phases 1, 2 and 3, the membrane allowed the removal of 56%, 70% and 64% of the SMP concentration in the sludge. SMPs were characterized by molecular weight (MW). A bimodal behavior was obtained, where fractions prevailed with an MW < 1 kDa, associated with SMPs as utilization-associated products (UAPs) caused fouling by the pore-blocking mechanism. The chemical analysis found that, in the SMPs, the unknown COD predominated over the known COD, such as carbohydrates and proteins. These results suggest that further studies in SMP characterization should focus on the unknown COD fraction to understand the membrane fouling in AnMBR systems better.

Quantum Reality in the Selective Reduction of a Benzofuran System.

Two 2,3-disubstituted benzofurans (1 and 2), analogs of gamma-aminobutyric acid (GABA), were synthesized to obtain their 2,3-dihydro derivatives from the Pd/C-driven catalytic reduction of the double bond in the furanoid ring. The synthesis produced surprising by-products. Therefore, theoretical calculations of global and local reactivity were performed based on Pearson's hard and soft acids and bases (HSAB) principle to understand the regioselectivity that occurred in the reduction of the olefinic carbons of the compounds. Local electrophilicity (ωk) was the most useful parameter for explaining the selectivity of the polar reactions. This local parameter was defined with the condensed Fukui function and redefined with the electrophilic (Pk+) Parr function. The similar patterns of both resulting sets of values helped to demonstrate the electrophilic behavior (soft acid) of the olefinic carbons in these compounds. The theoretical calculations, nuclear magnetic resonance, and resonance hybrids showed the moieties in each compound that are most susceptible to reduction.

Synthesis and Biological Evaluation of Novel 2,3-disubstituted Benzofuran Analogues of GABA as Neurotropic Agents.

BACKGROUND: Benzofurans are heterocyclic compounds with neurotropic activity. Some have been developed for the treatment of acute and degenerative neuronal injuries. OBJECTIVE: The study aimed to evaluate the in silico binding of some promising benzofurans on the GABA receptors, and the in vivo neurotropic activity of benzofuran analogues (BZF 6-10) of gamma-aminobutyric acid (GABA) on a seizure model. METHODS: The ligands with the best physicochemical attributes were docked on two GABA receptors (the alpha-1 subunit of GABAA-R and GBR1 subunit of GABAB-R). Selected benzofuran derivatives were synthesized by a multistep procedure and characterized. To examine the neurotropic effects, mice were pretreated with different concentrations of the compounds prior to PTZ- or 4- AP-induced seizures. We assessed acute toxicity, motor behavior, and the effects on seizures. RESULTS: The tested ligands that complied with Lipinski's rule of five were tested in silico with GABAA-R (ΔG = -5.51 to -5.84 kcal/mol) at the allosteric site for benzodiazepines. They bound to a similar cluster of residues as the reference compound (gaboxadol, ΔG = -5.51 kcal/mol). Synthesis was achieved with good overall yields (42-9.7%). Two compounds were selected for biological tests (BZF-7 and rac-BZF-10) on a mouse model of seizures, induced by pentylenetetrazol (PTZ) or 4-aminopyridine (4-AP). PTZ-induced seizures are associated with GABA receptors, and those 4-AP-induced with the blockage of the delayed rectifier-type potassium channel, which promotes the release of the NMDA-sensitive glutamatergic ionotropic receptor and other neurotransmitters. The biological assays demonstrated that BZF-7 and rac-BZF-10 do not protect against seizures. Indeed, BZF-7 increased the number of PTZ-induced seizures and decreased latency time. The 4-AP model apparently showed a potentiation of seizure effects after administration of the BZF-analogues, evidenced by the incidence and severity of the seizures and reduced latency time. CONCLUSION: The results suggest that the test compounds are GABAergic antagonists with stimulatory activity on the CNS.

Effectiveness of multidisciplinary approach in patients undergoing therapy for chronic hepatitis C.

OBJECTIVE: To assess the effect of a multidisciplinary approach on the outcome of treatment for hepatitis C virus infection. METHODS: This retrospective study was conducted at the gastroenterology division by primary care providers at Phoenix VA Healthcare system in Phoenix, Arizona, United States, and comprised clinical and laboratory data of all hepatitis C patients treated between November 2002 and December 2006. The patients were clinically evaluated to determine whether they were candidates for treatment with pegylated interferon a-2a or a-2b plus ribavirin. Patients were given detailed orientation prior to the therapy, and were closely monitored during the treatment. RESULTS: Of the 295 patients, 179(60.7%) received pegylated interferon a-2b and ribavirin and 116(39.3%) received pegylated interferon a-2a and ribavirin. Overall, 202(68.47%) had genotype 1 and 93 (31.52%) had non-genotype 1. Age range was 35 to 66 years (mean 51±8.51 and Mean BMI was 28.2±4.22), and the majority was Caucasian males who served in the Vietnam era. The overall sustained virological response was 120(40.7%). CONCLUSIONS: High sustained virological response was achieved among the participants.

Comparación del esquema antibiótico entre la Piperacilina-Tazobactam y Amikacina vs Metronidazol y Gentamicina en el tratamiento de la apendicitis complicada en niños / Comparison between two antibiotic schemes gentamycin-metronidazole vs. piperacillin-tazobactam and amikacin in treating complicated appendectomies in children

Introducción. Los pacientes que tuvieron complicaciones infecciosas post cirugía de apendicitis siguen usualmente un esquema de tratamiento establecido de antibióticos en el Hospital San Juan de Dios (HSJD). Se realizó un análisis retrospectivo de 60 pacientes pediátricos con apendicitis complicada a quienes se les efectuó una apendicectomía abierta y se utilizó el esquema antibiótico de metronidazol y gentamicina. Objetivo. Evaluar la eficacia del esquema de antibióticos usados. Metodología. El estudio se efectuó en la Unidad de Cirugía Pediátrica del HGSJD en el período de tiempo de enero a diciembre de 2013. Se evaluaron las complicaciones infecciosas en los pacientes que requirieron la omisión de los antibióticos mencionados y el inicio de la combinación de piperacilina tazobactam ­ amikacina. Resultados. Hubo 56 (93%) pacientes en quienes el esquema inicial de metronidazol ­ gentamicina fue el único empleado sin que presentaran complicación infecciosa alguna, mientras que 4 (7%) pacientes presentaron colecciones abdominales que requirieron el cambio a piperacilina tazobactam-amikacina con lo que resolvieron la sepsis abdominal. Conclusiones. La utilización de la combinación antibiótica de metronidazol-gentamicina continúa siendo eficiente en la población pediátrica con apendicitis aguda complicada que consulta a nuestro hospital dejando el empleo de la piperacilina tazobactam y amikacina como una alternativa terapéutica útil. Palabras clave: Apendicetomía, metronidazol-gentamicina, piperacilina-tazobactam, amikacina

Introduction: A retrospective study was conducted with 60 pediatric patients with diagnosis of complicated appendicitis, in which open appendectomy was performed and treated with metronidazole and gentamycin. Objective: To evaluate efficacy between the combination of a routinely stablished treatment of metronidazole and gentamycin and piperacillin-tazobactam with amikacin in the treatment of complicated appendectomies. Methodology: This retrospective study was conducted in the Pediatric Surgery Unit of the General Hospital San Juan de Dios from January to December 2013. The postoperative complications were assessed of patients who needed a change in antibiotic therapy to piperacillin tazobactam-amikacin. Results: Fifty-six patients (93%) in which the initial antibiotic combination was used recovered without any complications. Four (7%) patients developed intraabdominal collections and needed therapy with piperacillin tazobactam­amikacin with which they resolved the abdominal sepsis. The antibiotic combination gentamycin and metronidazole is still effective in the pediatric population with complicated acute appendicitis in our hospital, leaving the use of piperacillin tazobactam ­ amikacin as a useful alternative. Keywords: Appendectomy, metronidazole-gentamycin, piperacillin tazobactam-amikacyn

Microsporidiosis acquired through solid organ transplantation: a public health investigation.

BACKGROUND: Encephalitozoon cuniculi, a microsporidial species most commonly recognized as a cause of renal, respiratory, and central nervous system infections in immunosuppressed patients, was identified as the cause of a temporally associated cluster of febrile illness among 3 solid organ transplant recipients from a common donor. OBJECTIVE: To confirm the source of the illness, assess donor and recipient risk factors, and provide therapy recommendations for ill recipients. DESIGN: Public health investigation. SETTING: Two transplant hospitals and community interview with the deceased donor's family. PATIENTS: Three transplant recipients and the organ donor. MEASUREMENTS: Specimens were tested for microsporidia by using culture, immunofluorescent antibody, polymerase chain reaction,immunohistochemistry, and electron microscopy. Donor medical records were reviewed and a questionnaire was developed to assess for microsporidial infection. RESULTS: Kidneys and lungs were procured from the deceased donor and transplanted to 3 recipients who became ill with fever 7 to 10 weeks after the transplant. Results of urine culture, serologic,and polymerase chain reaction testing were positive for E. cuniculi of genotype III in each recipient; the organism was also identified in biopsy or autopsy specimens in all recipients. The donor had positive serologic test results for E. cuniculi. Surviving recipients received albendazole. Donor assessment did not identify factors for suspected E. cuniculi infection. LIMITATION: Inability to detect organism by culture or polymerase chain reaction in donor due to lack of autopsy specimens. CONCLUSION: Microsporidiosis is now recognized as an emerging transplant-associated disease and should be considered in febrile transplant recipients when tests for routinely encountered agents are unrevealing. Donor-derived disease is critical to assess when multiple recipients from a common donor are ill.

Growth inhibition of Streptococcus from the oral cavity by α-amyrin esters.

Five terpenoids were tested by the macrodilution broth method to determine their inhibition activity on cariogenic bacterial growth. In general, α-, β-amyrin and α-amyrin phenylacetate proved to be active, reducing the bacterial viability to less than 20%.

Epidemiología: [revisión] / Epidemiology: [review]

Las enfermedades diarreícas, constituyen un problema mundial, con altas tasas de morbilidad y mortalidad, especialmente en países en vías de desarrollo. Venezuela presentó, en el año 2008, 1.768.509 casos de diarrea, con un 40 por ciento en menores de 5 años. El total de muertes en menores de 5 años en el período 2000-2007 fue de 9311, siendo la tercera causa en este grupo de edad. Entre las bacterias, el género Salmonella, es el más frecuentemente aislado en brotes epidémicos. En niños menores de 6 años. E.coli enteropatógena fue el agente principal, seguido por E.coli enteroinvasiva, Aeromonas sp., salmonella sp y Shigella. Campylobacter es una de las bacterias más frecuentemente en las heces de los lactantes y niños en países en desarrollo. En algunos países, tener en cuenta al Vibrium Cholera y en diarreas nosocomiales al Clostridium difficile. En lactantes y preescolares la etiología viral es la más frecuente y el rotavirus el agente más común, causando aproximadamente 15000 muertes anuales en la región de las Américas. Otros virus causantes de diarreas , son los calicivirus y los adenovirus. Los factores de riesgo están relacionados con el medio ambiente, estilos de vida, factores dependientes de la biología humana y de los sistemas de servicios de salud. Las medidas de prevención y control epidemiológico más importantes son la promoción de la lactancia materna, hábitos adecuados de higiene y saneamiento ambiental, uso adecuado de antibióticos, terapia de rehabilitación oral e intravenosa, inmunizaciones, mejoría de las condiciones socio sanitarias y sistemas eficientes de vigilancia epidemiológica.

Diarrheal diseases constitute a global problem, with high rates of morbidity and mortality, particulary in developing countries. Venezuela, for 2008, presented 1.768.509 cases of diarrhea, with 40% in children under 5 years. The total number of dealths in children under years of age in the period 2000-2007 was 9311, being the third learding cause in this age group. Among causing bacterias, Salmonella in the most isolated in outbreaks. In children under 6 years, E.Coli was the principal agent, followed by E.coli., enteroinvasive, Aeromonas sp., Salmonella sp, and Shigella. Campylobacter is one of the most common bacterial in the feces of infants and children in developing countries. In some countries, Vibrium Cholera and Clostridium difficile should be considered. In infants and preshool children, viral etiology is the most frequent and rotavirus the most common agent, causing about 15000 deaths annually in the region of the Americas. Other viruses that cause diarrhea are the calciviruses and adenoviruses. Risk factors are related to the environment, lifestyles, factors dependent on human biology and health care systems. The most important prevention and control measures are the promotion of breastfeeding, proper habits of hygiene and sanitation, proper use of antibiotics, oral and intravenous rehydration therapies, immunization, improvement of sanitary conditions and efficient surveillance systems.

Evaluation of the hydroxynitrile lyase activity in cell cultures of capulin (Prunus serotina).

Enzymatic preparations obtained from young plants and cell cultures of capulin were screened for hydroxynitrile lyase activity. The three week old plants, grown under sterile conditions, were used to establish a solid cell culture. Crude preparations obtained from this plant material were evaluated for the transformation of benzaldehyde to the corresponding cyanohydrin (mandelonitrile). The results show that the crude material from roots, stalks, and leaves of young plants and calli of roots, stalks, internodes and petioles biocatalyzed the addition of hydrogen cyanide (HCN) to benzaldehyde with a modest to excellent enantioselectivity.

Biocatalytic oxidative kinetic resolution of (±)-4-(chlorophenyl)phenylmethanol by Nocardia corallina B-276

Chiral diarylmethanols are versatile building blocks for the preparation of biologically active substances, but they are difficult to obtain in enantiopure form. We used Nocardia corallina B-276 for the oxidative kinetic resolution of (+/-)-4-(chlorophenyl)phenylmethanol, 1. Two experimental methods were used: 1) Suspension of cells in a phosphate buffer solution and 2) Cells in the culture media, in a 3-L bioreactor. After 36 hrs using the first method, the ketone/alcohol ratio was 56/44 and the unoxidized alcohol had an enantiomeric ratio of 93/7, predominating the R-alcohol.

Tratamiento del linfagioma en niños con fraciones ribosómicas bacterianas / Treatment of lymphangioma in children with bacterial ribosomal fractions

Introducción: el propósito del presente estudio fue demostrar la efectividad del extracto de las fracciones ribosómicas bacterianas como tratamiento del linfangioma en niños. Material y métodos: se realizó un análisis prospectivo de enero de 2003 a enero de 2006 de los pacientes que consultaron con diagnóstico de linfangioma en quienes se administró intracavitariamente extracto de fracciones ribosómicas bacterianas como único régimen terapéutico. Se aplicaron de 1 a 3 infiltraciones seriados con un intervalo de 1 mes entre cada uno...