Age differences to methylphenidate-NAc neuronal and behavioral recordings from freely behaving animals.

Methylphenidate (MPD) is a psychostimulant that is widely prescribed to treat attention deficit-hyperactivity disorder, but it is abused recreationally as well. The nucleus accumbens (NAc) is part of the motivation circuit implicated in drug-seeking behaviors. The NAc neuronal activity was recorded alongside the behavioral activity from young and adult rats to determine if there are significant differences in the response to MPD. The same dose of MPD elicits behavioral sensitization in some animals and behavioral tolerance in others. In adult animals, higher doses of MPD resulted in a greater ratio of tolerance/sensitization. Animals who responded to chronic MPD with behavioral sensitization usually exhibited further increases in their NAc neuronal firing rates as well. Different upregulations of transcription factors (ΔFOSB/CREB), variable proportions of D1/D2 dopamine receptors, and modulation from other brain areas may predispose certain animals to express behavioral and neuronal sensitization versus tolerance to MPD.

Anaerobic RSH-dependent tellurite reduction contributes to Escherichia coli tolerance against tellurite.

BACKGROUND: Tellurium is a rare metalloid that exerts high toxicity on cells, especially on bacteria, partly due to reactive oxygen species (ROS) generation. Moreover, it has also been observed that tellurite can target free cell thiols groups (RSH) (i.e. reduced glutathione (GSH)), enhancing the cellular redox imbalance. Additionally, in vitro experiments have suggested that several enzymes can reduce tellurite (IV) to its elemental form (0); where RSH present on their active sites may be responsible for the process. Nevertheless, the mechanisms implemented by bacteria for tellurite reduction and its role in resistance have not been evaluated in vivo. RESULTS: This work shows that tellurite reduction to elemental tellurium is increased under anaerobic conditions in E. coli cells. The in vivo tellurite reduction is related to the intracellular concentration of total RSH, in the presence and absence of oxygen. This metabolization of tellurite directly contributes to the resistance of the bacteria to the oxyanion. CONCLUSIONS: We demonstrated that in vivo tellurite reduction is related to the intracellular thiol concentration, i.e. large availability of cellular RSH groups, results in a more significant reduction of tellurite. Furthermore, we observed that, when the bacterium exhibits less resistance to the oxyanion, a decreased tellurite reduction was seen, affecting the growth fitness. Together, these results let us propose that tellurite reduction and the intracellular RSH content are related to the oxyanion bacterial resistance, this tripartite mechanism in an oxygen-independent anaerobic process.

Bacterial phototoxicity of biomimetic CdTe-GSH quantum dots.

AIM: Fluorescent semiconductor nanoparticles or quantum dots (QDs) have excellent properties as photosensitizers in photodynamic therapy. This is mainly a consequence of their nanometric size and the generation of light-activated redox species. In previous works, we have reported the low-cost biomimetic synthesis of glutathione (GSH) capped QDs (CdTe-GSH QDs) with high biocompatibility. However, no studies have been performed to determine their phototoxic effect. The aim of this work was to characterize the light-induced toxicity of green (QDs500 ) and red (QDs600 ) QDs in Escherichia coli, and to study the molecular mechanism involved. METHODS AND RESULTS: Photodegradation and reduction power of biomimetic QDs was determined to analyse their potential for radical generation. Escherichia coli cells were exposed to photoactivated QDs and viability was evaluated at different times. High toxicity was determined in E. coli cells exposed to photoactivated QDs, particularly QDs500 . The molecular mechanism involved in QDs phototoxicity was studied by determining Cd2+ -release and intracellular reactive oxygen species (ROS). Cells exposed to photoactivated QDs500 presented high levels of ROS. Cells exposed to photoactivated QDs500 presented high levels of ROS. Finally, to understand this phenomenon and the importance of oxidative and cadmium-stress in QDs-mediated phototoxicity, experiments were performed in E. coli mutants in ROS and Cd2+ response genes. As expected, E. coli mutants in ROS response genes were more sensitive than the wt strain to photoactivated QDs, with a higher effect in green-QDs500 . No increase in phototoxicity was observed in cadmium-related mutants. CONCLUSION: Obtained results indicate that light exposure increases the toxicity of biomimetic QDs on E. coli cells. The mechanism of bacterial phototoxicity of biomimetic CdTe-GSH QDs is mostly associated with ROS generation. SIGNIFICANCE AND IMPACT OF THE STUDY: The results presented establish biomimetic CdTe-GSH QDs as a promising cost-effective alternative against microbial infections, particularly QDs500 .

Understanding gold toxicity in aerobically-grown Escherichia coli.

BACKGROUND: There is an emerging field to put into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. RESULTS: We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. CONCLUSIONS: Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium's oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.

A comparative analysis of tellurite detoxification by members of the genus Shewanella.

The increasing industrial utilization of tellurium has resulted in an important environmental pollution with the soluble, extremely toxic oxyanion tellurite. In this context, the use of microorganisms for detoxifying tellurite or tellurium biorecovery has gained great interest. The ability of different Shewanella strains to reduce tellurite to elemental tellurium was assessed; the results showed that the reduction process is dependent on electron transport and the ∆pH gradient. While S. baltica OS155 showed the highest tellurite resistance, S. putrefaciens was the most efficient in reducing tellurite. Moreover, pH-dependent tellurite transformation was associated with tellurium precipitation as tellurium dioxide. In summary, this work highlights the high tellurite reduction/detoxification ability exhibited by a number of Shewanella species, which could represent the starting point to develop friendly methods for the recovery of elemental tellurium (or tellurium dioxide).

An approach to utilize the artificial high power LED UV-A radiation in photoreactors for the degradation of methylene blue.

Utilization of UV LED light is trending in the development of photoreactors for pollutant treatment. In this study, two different geometries were studied in the degradation of methylenebBlue (MB) using high power UVA LED as a source of light. The dosage, initial concentration, electric power, and H2O2 addition were evaluated in the two geometries: a mini CPC (Cilindrical Parabolic Collector) and a vertical cylindrical with external irradiation both coupled with LED UVA. Best degradation was obtained for 0.3 g L-1 TiO2, 40 min, and 15 ppm of MB of initial concentration in the standard batch reactor. It was found that the best system was a cpc geometry. Also, hydrogen peroxide was used as an electron acceptor and 97% degradation was obtained in 30 min with 10 mM H2O2 and 0.4 g TiO2/L. Power of the LEDs was also evaluated and it was found that 20 W m-2 is the best operational condition to achieve the best MB degradation avoiding the oxidant species recombination.

Use of an experimental model to evaluate infection resistance of meshes in abdominal wall surgery.

BACKGROUND: Staphylococcal species are the most common organisms causing prosthetic mesh infections, however, infections due to rapidly growing mycobacteria are increasing. This study evaluates the resistance of biomaterial for abdominal wall prostheses against the development of postoperative infection in a rat model. MATERIAL AND METHODS: In 75 rats, we intramuscularly implanted three different types of prostheses: (1) low-density polypropylene monofilament mesh (PMM), (2) high-density PMM, and (3) a composite prosthesis composed of low-density PMM and a nonporous hydrophilic film. Meshes were inoculated with a suspension containing 108 colony-forming units of Staphylococcus aureus, Staphylococcus epidermidis, Mycobacterium fortuitum, or Mycobacterium abscessus before wound closure. Animals were sacrificed on the eighth day postoperatively for clinical evaluation, and the implants were removed for bacteriologic analyses. RESULTS: Prostheses infected with S aureus showed a higher bacterial viability, worse integration, and clinical outcome compared with infection by other bacteria. Composite prostheses showed a higher number of viable colonies of both M fortuitum and Staphylococcus spp., with poorer integration in host tissue. However, when the composite prosthesis was infected with M abscessus, a lower number of viable bacteria were isolated and a better integration was observed compared with infection by other bacteria. CONCLUSIONS: Considering M abscessus, a smaller collagen-free contact surface shows better resistance to infection, however, depending on the type of bacteria, prostheses with a large surface, and covered with collagen shows reduced resistance to infection, worse integration, and worse clinical outcome.

Effect of gamma irradiation on phenol content, antioxidant activity and biological activity of black maca and red maca extracts (Lepidium meyenii walp).

This study was performed to determine the effects of gamma irradiation on UV spectrum on maca, total content of polyphenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and in vivo biological activities of red and black maca extracts (Lepidium meyenii). Adult mice of the strain Swiss aged 3 months and weighing 30-35 g in average were used to determine biological activities. Daily sperm production, effect on testosterone-induced prostate hyperplasia and forced swimming test were used to determine the effect of irradiation on biological activities of maca extracts. Irradiation did not show differences in UV spectrum but improves the amount of total polyphenols in red maca as well as in black maca extracts. In both cases, black maca extract has more content of polyphenols than red maca extract (p < 0.01). Gamma irradiation significantly increased the antioxidant capacity (p < 0.05). No difference was observed in daily sperm production when irradiated and nonirradiated maca extract were administered to mice (p > 0.05). Black maca extract but not red maca extract has more swimming endurance capacity in the forced swimming test. Irradiation of black maca extract increased the swimming time to exhaustion (p < 0.05). This is not observed with red maca extract (p > 0.05). Testosterone enanthate (TE) increased significantly the ventral prostate weight. Administration of red maca extract in animals treated with TE prevented the increase in prostate weight. Irradiation did not modify effect of red maca extract on prostate weight (p > 0.05). In conclusion, irradiation does not alter the biological activities of both black maca and red maca extracts. It prevents the presence of microorganisms in the extracts of black or red maca, but the biological activities were maintained.

HIV virological rebounds but not blips predict liver fibrosis progression in antiretroviral-treated HIV/hepatitis C virus-coinfected patients.

OBJECTIVES: Antiretroviral interruption is associated with liver fibrosis progression in HIV/hepatitis C virus (HCV) coinfection. It is not known what level of HIV viraemia affects fibrosis progression. METHODS: We evaluated 288 HIV/HCV-coinfected cohort participants with undetectable HIV RNA (<50 HIV-1 RNA copies/mL) on two consecutive visits while on combination antiretroviral therapy (cART) without fibrosis [aspartate aminotransferase to platelet ratio index (APRI) <1.5], end-stage liver disease or HCV therapy. An HIV blip was defined as a viral load of ≥ 50 and <1000 copies/mL, preceded and followed by undetectable values. HIV rebound was defined as: (i) HIV RNA ≥ 50 copies/mL on two consecutive visits, or (ii) a single HIV RNA measurement ≥ 1000 copies/mL. Multivariate discrete-time proportional hazards models were used to assess the effect of different viraemia levels on liver fibrosis progression (APRI ≥ 1.5). RESULTS: The mean age of the patients was 45 years, 74% were male, 81% reported a history of injecting drug use, 51% currently used alcohol and the median baseline CD4 count was 440 [interquartile range (IQR) 298, 609] cells/µL. Fifty-seven (20%) participants [12.4/100 person-years (PY); 95% confidence interval (CI) 9.2-15.7/100 PY] progressed to an APRI ≥ 1.5 over a mean 1.1 (IQR 0.6, 2.0) years of follow-up time at risk. Virological rebound [hazard ratio (HR) 2.3; 95% CI 1.1, 4.7] but not blips (HR 0.5; 95% CI 0.2, 1.1) predicted progression to APRI ≥ 1.5. Each additional 1 log10 copies/mL HIV RNA exposure (cumulative) was associated with a 20% increase in the risk of fibrosis progression (HR 1.2; 95% CI 1.0-1.3). CONCLUSIONS: Liver fibrosis progression was associated with HIV rebound, but not blips, and with increasing cumulative exposure to HIV RNA, highlighting the importance of achieving and maintaining HIV suppression in the setting of HIV/HCV coinfection.

Life cycle of Raoiella indica (Acari: Tenuipalpidae) on ornamental plants, mostly Arecaceae.

The red palm mite, Raoiella indica Hirst, has been primarily found associated with coconut and musaceous plants in the New World. However, it has also been recorded on several other palms, heliconiaceous and zingiberaceous species. This study was conducted to evaluate the suitability of different botanical families on which R. indica has been collected in the field and of arecaceous plants of the natural vegetation of the neotropics. In total, ten species of Arecaceae as well as Heliconia psittacorum [Heliconiaceae] and Alpinia purpurata [Zingiberacae] were evaluated, using coconut as a control. The study was carried out under controlled conditions (29 ± 0.5 °C, 60 ± 10% RH and photoperiod 12 h of light). Raoiella indica was able to complete immature development only on coconut, Adonidia merrillii, Ptychosperma macarthurii, H. psittacorum and A. purpurata. Duration of the immature phase (egg-adult) ranged between 21.5 days on coconut to 34.1 days on A. purpurata. Longevity was at least 50% greater and oviposition at least 38% higher on coconut than on other plants. Intrinsic rate of increase (rm) was higher on coconut (0.166) and A. merrillii (0.042), but negative on the other two plant species. Raoiella indica could not reach adulthood on any of the other ten arecaceous species considered in the study. The results suggested R. indica to be a threat to A. merrillii in addition to coconut, but not to other evaluated plants. However, complementary studies should be conducted to investigate whether the experimental procedures adopted in this study could not have prevented the mite from a better performance than it could have been under field conditions, especially in relation to Mauritia flexuosa, one of the dominant arecaceous plants in South America.

Patient satisfaction and quality of life following laparoscopic Nissen fundoplication.

BACKGROUND: Today, antireflux surgery has an established position in the management of gastroesophageal reflux disease. Some case series have shown good short-term results, but there is still little information regarding long-term results. Studies have recently focused on evaluating residual symptomatology and its impact on quality of life. OBJECTIVES: To determine the postoperative quality of life and degree of satisfaction in patients that underwent laparoscopic Nissen fundoplication. PATIENTS AND METHODS: A total of 100 patients (59 women and 41 men) were studied after having undergone laparoscopic Nissen fundoplication. The variables analyzed were level of satisfaction, gastrointestinal quality of life index (GIQLI), residual symptoms, and the Visick scale. RESULTS: No variation was found in relation to sex; 49 men and 51 women participated in the study. The mean age was 49 years. The degree of satisfaction encountered was: satisfactory in 81 patients, moderate in 3, and bad in 2 patients. More than 90% of the patients would undergo the surgery again or recommend it. The Carlsson score showed improvement at the end of the study (p<0.05). In relation to the GIQLI, a median of 100.61 points±21.624 was obtained. Abdominal bloating, regurgitation, and early satiety were the most frequent residual symptoms. The effect on lifestyle measured by the Visick scale was excellent. CONCLUSIONS: The level of satisfaction and quality of life obtained were comparable with reported standards; and the residual symptoms after antireflux surgery were easily controlled.

[Neuroanatomical mapping of inhibitory attention and working memory with functional magnetic resonance imaging in healthy children]. / Mapeo neuroanatómico de atención inhibitoria y memoria de trabajo con resonancia magnética funcional en niños sanos.

INTRODUCTION: The objective is to produce an average brain activation mapping template in healthy children using functional magnetic resonance imaging (fMRI), with specific paradigms for activating inhibitory attention and working memory functions. SUBJECTS AND METHODS: A nutritional and neuropsychological evaluation was performed on 87 right-handed children. The inclusion criteria were met by 30 children (15 boys and 15 girls) between 9 and 11 years old, who were studied with fMRI in two inhibitory attention tests (Go/No Go), with food cues, a working memory test (Continuous Performance Test Identical Pairs) and measurement of anatomical volumes. These data were subsequently processed with the FSL-v5 program, with a threshold of p < 0.05 (cluster-wise). The brain areas activated were located using a standard Montreal Neurological Institute brain template and the Harvard-Oxford structural cortical atlas. RESULTS: The inhibitory attention tests showed activation frontal areas predominantly on the right, and the cingulate, parietal and occipital areas, with preponderance in occipital areas in the food cues test. In the Continuous Performance Test-Identical Pairs test, activation was obtained predominantly in the occipital, frontal and parietal areas. CONCLUSIONS: Brain activity mapping templates are obtained in healthy children with tests for inhibitory attention, food cues and working memory. The activation areas are mostly those reported in the literature. This provides baseline brain activation patterns for studying pathologies related to inhibitory attention, impulsivity and working memory.

TITLE: Mapeo neuroanatómico de atención inhibitoria y memoria de trabajo con resonancia magnética funcional en niños sanos.Introducción. El objetivo es lograr una plantilla de mapeo de activación cerebral promedio en niños sanos usando la resonancia magnética funcional (RMf), con paradigmas específicos para activar funciones de atención inhibitoria y de memoria de trabajo. Sujetos y métodos. Se realizó una evaluación nutricional y neuropsicológica a 87 niños diestros. Cumplieron los criterios de inclusión 30 (15 niños y 15 niñas) entre 9 y 11 años, a quienes se estudió con RMf con realización de dos pruebas de atención inhibitoria (Go/No Go), con letras e imágenes de alimentos, un test de memoria de trabajo (Test de Atención Continua-Pares Idénticos) y obtención de volúmenes anatómicos. Los datos posteriormente se procesaron con el programa FSL-v5 con un umbral de p < 0,05 (cluster-wise). Las áreas cerebrales activadas se localizaron utilizando una plantilla cerebral estándar del Montreal Neurological Institute y el atlas cortical estructural de Harvard-Oxford. Resultados. En las pruebas de atención inhibitoria hay activación en áreas frontales de predominio derecho, cíngulo, parietales y occipitales, con preponderancia en áreas occipitales en la prueba con alimentos. En la prueba Test de Atención Continua-Pares Idénticos se obtuvo activación de predominio en áreas occipitales, frontales y parietales. Conclusiones. Se obtienen plantillas de mapeo de actividad cerebral en niños sanos con test de atención inhibitoria, de alimentos y de memoria de trabajo. Las áreas de activación corresponden mayoritariamente a las descritas en la bibliografía. Esto nos permite tener patrones basales de activación cerebral para estudiar patologías relacionadas con la atención inhibitoria, la impulsividad y la memoria de trabajo.

Allergic rhinitis and associated factors in schoolchildren from Bogota, Colombia.

BACKGROUND: Allergic rhinitis is one of the most frequent chronic diseases among children. The objective of the study was to assess the prevalence of and the factors associated with self-reported allergic rhinitis symptoms in schoolchildren from Bogota, Colombia. METHODOLOGY/PRINCIPAL: We followed the International Study of Asthma and Allergies in Childhood (ISAAC) methodology. Our sample included 3,256 children aged 6 - 7 and 3,830 adolescents aged 13 - 14 years. RESULTS: The prevalence of self-reported allergic rhinitis symptoms was 30.8% among children and 36.6% among adolescents. Factors associated with self-reported allergic rhinitis among children included current asthma and atopic dermatitis symptoms; use of acetaminophen in the first year of life and in the last 12 months; antibiotic use in the first year of life; high- school and university maternal education; smokers at home; and caesarean delivery. Among adolescents, associated factors included current asthma and atopic dermatitis symptoms; current acetaminophen use once per month; frequent fast-food consumption; cat exposure at home; and smoking. CONCLUSION: Further exploration of factors associated with allergic rhinitis symptoms is needed.

Adolescent rats respond differently to methylphenidate as compared to adult rats- concomitant VTA neuronal and behavioral Recordings.

Methylphenidate (MPD) is the most widely prescribed psychostimulant used in adolescents and adults to treat attention-deficit/hyperactivity disorder (ADHD). The recreational use of MPD is becoming more prevalent because of its ability to improve cognitive enhancement. The ventral tegmental area (VTA) of the brain is highly associated with reward, cognition and addiction to drugs including psychostimulants like MPD. The VTA neuronal activity was recorded alongside the horizontal behavioral activity from freely behaving non-anesthetized rats. Four adolescent and four adult groups were treated with either saline, 0.6, 2.5 or 10.0 mg/kg MPD. In both adolescent and adult animals, the animals responded to MPD in a dose-dependent manner, such that as the dose of MPD increased, more animals and more VTA unit responded to the drug. The same doses of MPD elicited in some animals behavioral and neuronal sensitization and in other animals behavioral and neuronal tolerance. In the 0.6 and 10.0 mg/kg MPD dose groups there were significant differences between the age groups for how many animals expressed behavioral sensitization and behavioral tolerance to chronic MPD exposure. Additionally, the animal's behavioral response to MPD by excitation or attenuation of activity did not always correlate to the VTA neuronal response, and the age group with significantly higher behavioral responses did not always correlate to the age group with significantly higher VTA neuronal responses for a given MPD dose. These findings differ from similar studies recorded from the prefrontal cortex (PFC), which exhibited behavioral responses continuously directly correlated to PFC responses for increasing MPD doses. This demonstrates that unlike other areas of the brain, there is not a direct relationship between VTA firing and behavioral activity, suggesting that there is input or modulation of this area from elsewhere in the brain. Further investigation is needed to clearly understand the relationship between VTA firing rates and behavioral responses to different MPD doses, especially given the significant differences in response between young and adult animals and the increasing use of the drug in adolescent populations.

Risk factors associated with postoperative morbidity and mortality in D2 radical gastrectomy for gastric cancer.

INTRODUCTION AND AIMS: Surgery is the main treatment for gastric cancer. D2 radical gastrectomy is associated with a variable postoperative morbidity and mortality rate worldwide. The aim of the present study was to identify the risk factors associated with the postoperative morbidity and mortality of D2 radical gastrectomy, with curative intent, for gastric cancer. MATERIALS AND METHODS: A retrospective case series was conducted, in which the medical records were reviewed of patients with gastric cancer that underwent D2 radical gastrectomy, within the time frame of January 2014 and December 2018. Univariate and multivariate analyses were carried out to identify the risk factors related to postoperative morbidity and mortality within 90 days. RESULTS: The percentages of postoperative morbidity and mortality in 691 patients were 23.3% and 3.3%, respectively. In the multivariate analysis, age ≥70 years (OR = 1.85, 95% CI: 1.25-2.76), ASA III-IV (OR = 2.06, 95% CI: 1.28-3.34), total gastrectomy (OR = 1.96, 95% CI:1.19-3.23), and pancreatosplenectomy (OR = 5.41, 95% CI: 1.42-20.61) were associated with greater postoperative morbidity, and age ≥70 years (OR = 4.92, 95% CI:1.78-13.65), lower BMI (OR = 0.81, 95% CI: 0.71-0.92), and hypoalbuminemia (OR = 0.91, 95% CI: 0.85-0.98) were associated with greater mortality in distal and total D2 radical gastrectomy. CONCLUSIONS: D2 radical gastrectomy for gastric cancer was shown to be a safe treatment, with low postoperative morbidity and mortality rates. Age ≥70 years, ASA III-IV, total gastrectomy, and pancreatosplenectomy were factors associated with a higher complication rate. Age ≥70 years, lower BMI, and hypoalbuminemia were mortality predictors in distal and total radical gastrectomy.

Concordance of the ACR TI-RADS.

BACKGROUND: Ultrasonography (US) is the method of choice for evaluating thyroid nodules. In 2017, the American College of Radiology (ACR) created a classification system based on US characteristics. For the system to be adopted, it must be reproducible. OBJECTIVES: To determine the intraobserver and interobserver variability of the ACR TI-RADS. METHODS: Cross-sectional study; three radiologists with different levels of experience used the ACR TI-RADS to classify 100 nodules on two occasions one month apart, and we calculated the intraobserver and interobserver variability. RESULTS: Regarding intraobserver variability, the first radiologist had nearly perfect concordance for composition, echogenicity, shape, and margins and substantial concordance for echogenic foci; the second radiologist had nearly perfect concordance for composition, echogenicity, shape, and margins and substantial concordance for echogenic foci, and the third radiologist had nearly perfect concordance for composition, echogenicity, and shape and substantial concordance for margins and echogenic foci. The interobserver concordance was calculated for the two readings; the concordance was substantial except for shape in the first reading and for echogenicity and margins in the second reading, which had moderate concordance. CONCLUSIONS: The ACR TI-RADS classification system is reproducible.

Risk factors associated with postoperative morbidity and mortality in D2 radical gastrectomy for gastric cancer. / Factores de riesgo asociados con morbilidad y mortalidad postoperatoria en gastrectomía radical D2 por cáncer gástrico.

INTRODUCTION AND AIMS: Surgery is the main treatment for gastric cancer. D2 radical gastrectomy is associated with a variable postoperative morbidity and mortality rate worldwide. The aim of the present study was to identify the risk factors associated with the postoperative morbidity and mortality of D2 radical gastrectomy, with curative intent, for gastric cancer. MATERIALS AND METHODS: A retrospective case series was conducted, in which the medical records were reviewed of patients with gastric cancer that underwent D2 radical gastrectomy, within the time frame of January 2014 and December 2018. Univariate and multivariate analyses were carried out to identify the risk factors related to postoperative morbidity and mortality within 90 days. RESULTS: The percentages of postoperative morbidity and mortality in 691 patients were 23.3% and 3.3%, respectively. In the multivariate analysis, age ≥ 70 years (OR=1.85, 95% CI: 1.25-2.76), ASA III-IV (OR=2.06, 95% CI: 1.28-3.34), total gastrectomy (OR=1.96, 95% CI:1.19-3.23), and pancreatosplenectomy (OR=5.41, 95% CI: 1.42-20.61) were associated with greater postoperative morbidity, and age≥70 years (OR=4.92, 95% CI:1.78-13.65), lower BMI (OR=0.81, 95% CI: 0.71-0.92), and hypoalbuminemia (OR=0.91, 95% CI: 0.85-0.98) were associated with greater mortality in distal and total D2 radical gastrectomy. CONCLUSIONS: D2 radical gastrectomy for gastric cancer was shown to be a safe treatment, with low postoperative morbidity and mortality rates. Age≥70 years, ASA III-IV, total gastrectomy, and pancreatosplenectomy were factors associated with a higher complication rate. Age≥70 years, lower BMI, and hypoalbuminemia were mortality predictors in distal and total radical gastrectomy.

[Phenotypic and genotypic detection of the production of carbapenemases type NDM-1 and KPC in isolated Enterobacteriaceae in a clinical laboratory in Maracay, Venezuela]. / Detección fenotípica y genotípica de la producción de carbapenemasas tipo NDM-1 y KPC en enterobacterias aisladas en un laboratorio clínico en Maracay, Venezuela.

BACKGROUND: The production of carbapenem-hydrolyzing ß-lactamases is one of the most concerning resistance mechanisms since it eliminates the last therapeutic option against multidrug resistant microorganisms. AIM: To determine the production of KPC and NDM-1 type carbapenemases, using phenotypic and genotypic methods, in isolated enterobacteria in a clinical laboratory in the city of Maracay, Venezuela. METHODS: The production of carbapenemases was determined by phenotypic (according to the Malbrán algorithm) and genotypic methods (amplification of the blaNDM-1 and blaKPC genes by PCR) in clinical isolates of Enterobacteriaceae during the period March-August 2018. RESULTS: 605 Enterobacteriaceae of different species were identified, being Escherichia coli the strain with the highest percentage of isolation (61.3%), followed by Klebsiella pneumoniae (14.9%). Sixteen strains (2.64%) were positive for carbapenemases production: 13 strains of K. pneumoniae and three of the Enterobacter cloacae complex. PCR showed that 14 strains (87.5%) carry the blaNDM-1 gene and two strains (12.5%) the blaKPC gene; 100% agreement was observed between phenotypic determination and PCR for both groups of enzymes. CONCLUSIONS: The results of this study showed a higher incidence of metallo-ß-lactamase type NDM-1, which rapid dissemination and consequently difficult control has been cause of epidemiological alert. The identification of the type of enzyme would allow establishing more accurate management and control strategies in order to eradicate these pathogens.

Molecular phylogenetics and phylogeography of the white-fronted capuchin (Cebus albifrons; Cebidae, Primates) by means of mtCOII gene sequences.

A total of 696 base pairs (bp) of the mitochondrial COII gene were sequenced from 118 individuals of Cebus albifrons (plus an individual of Cebus olivaceus) sampled from diverse geographical areas of Colombia, Peru, Ecuador and Brazil. These animals represented all of the C. albifrons's taxa described by Hershkovitz (1949) in Colombia and Peru (10 out of 13 subspecies are described by this author). The sequences analyzed demonstrate the existence of three well defined groups in northern Colombia (trans-Andean): malitosus, versicolor-pleei-cesarae and leucocephalus. They arose from at least, three distinct migrations from different Amazonian groups. Five different Amazonian and Eastern Llanos C. albifrons's groups (I, II, III, IV, and V) were also found. In many Amazonian localities, some of these groups live in sympatry probably by secondary expansion after their respective formations. Amazonian group I is closely related to the versicolor-pleei-cesarae group, malitosus is closely related to Amazonian group V, while leucocephalus is closely related to Amazonian group IV. Nevertheless, our genetic analysis could not resolve the genetic relationships among the main C. albifrons groups. The ρ-statistic applied to the median-joining network yielded that the major part of the temporal splits estimated occurred in the Pleistocene, reinforcing the importance of the Pleistocene refugia during the evolution of C. albifrons.

Characterization of bacteria using its O-antigen with surface-enhanced Raman scattering.

The O-antigen determines the specificity of bacterial serotype, a sort of bacterial fingerprinting. In this work we report the extraction, purification and characterization of the O-antigen of two pathogenic bacteria, Escherichia coli O16 and Salmonella typhimurium. Molecular fingerprints found in the vibrational spectra represent a powerful analytical technique for identification (or differentiation) of molecular moieties in complex systems such as pathogens. In addition, advantages of vibrational Raman scattering are unique thanks to the high sensitivity and specificity achieved via surface-enhanced Raman scattering (SERS). SERS is used here to take advantage of characteristic vibrational frequency differences of O-antigens, thus allowing bacterial differentiation. Characteristic fundamental vibrational modes associated with the monosaccharide N-acetylglucosamine and deformations of the O-antigen chains provide the main spectroscopic differences between the O-antigens of E. coli O16 and S.typhimurium.