Encuesta entomológica y caracterización de las viviendas con el vector de la enfermedad de Chagas, en aldea Chuchuapa, Santa Rosa, Guatemala / Entomological survey and characterization of houses with the vector of Chagas disease, in Chuchuapa village, Santa Rosa, Guatemala

En Guatemala en el 2015, el Ministerio de Salud Pública y Asistencia Social (MSPAS) reportó nuevos casos de la enfermedad de Chagas en la región suroriental del país, siendo Santa Rosa uno de los departamentos endémicos en donde Triatoma dimidiata es el principal transmisor. Se estimó la infestación de T. dimidiata en la aldea Chuchuapa, municipio de Santa María Ixhuatán, de abril a junio de 2019, se calcularon los índices en-tomológicos y se caracterizaron intra y peridomiciliar 149 viviendas (79.67% de las viviendas habitadas). Los datos se obtuvieron mediante un cuestionario mixto, en entrevista cara a cara y evaluación de las viviendas, por un equipo profesional experimentado, mediante el método y protocolo estándar hombre-hora. Se capturaron 20 triatominos en 10 viviendas, con un índice de infestación de 6.71% (10/149), un índice de densidad de 13.42% (20/149), 19 triatominos intradomiciliares y uno peridomiciliar, con un índice de infección natural por Tr y pano-soma cruzi intradomiciliar de 26.3% (5/19), índice de infección natural por T. cr u z i peridomiciliar de 100.0% (1/1) e índice de infección natural por T. c r u z i en los triatominos capturados de 30.0 % (6/20). Las viviendas infestadas presentaron techo de lámina, pared de bajareque con grietas y sin repello, piso de tierra y afiches en la pared, acumulación de leña u otros materiales tanto intra como peridomiciliar, convivencia con animales domésticos y tenencia de animales de corral. Los resultados representan un alto riesgo para la transmisión de la enfermedad de Chagas entre los habitantes de la aldea.

In Guatemala in 2015, the Ministry of Public Health and Social Assistance reported new cases of Chagas disease in the southeastern region of the country, with Santa Rosa being one of the endemic departments where Tr ia-toma dimidiata is the main transmitter. The infestation of T. dimidiata was estimated in the Chuchuapa village, municipality of Santa María Ixhuatán, from April to June 2019, the entomological indices were calculated and 149 dwellings were characterized intradomiciliary and peridomiciliary (79.67% of the inhabited dwellings). The data were obtained through a mixed questionnaire, in a face-to-face interview and evaluation of the dwellings, by an experienced professional team, using the standard man-hour method and protocol. 20 triatomines were captured in 10 homes, with an infestation index of 6.71% (10/149), a density index of 13.42% (20/149), 19 intradomiciliary triatomines and one peridomiciliary, with a natural infection index by intradomiciliary Trypanosomacruzi of 26.3% (5/19), natural infection index by peridomiciliary T. c r u z i of 100.0% (1/1) and natural infection index by T. c r u z i in captured triatomines of 30.0% (6/20). The infested dwellings have a sheet roof, awattle and daub wall with cracks and no wall plaster, dirt and posters on the wall, accumulation of firewood and other materials in both intradomiciliary and peridomiciliary, living with domestic animals and keeping poultry animals. The results represent a high risk for the transmission of Chagas disease among the villager.

Chagas disease: Importance of rats as reservoir hosts of Trypanosoma cruzi (Chagas, 1909) in western Mexico.

In Mexico, the role of most species of mammals involved in the transmission cycle of Trypanosoma cruzi Chagas, 1909 is poorly known. It was carried out a study to investigate the importance of rats as reservoir of T. cruzi in western Mexico, an area with important risk of transmission of T. cruzi to human. Thirty-eight human dwellings were searched on two representative towns of western Mexico along twelve months for collection of rats and triatomines. Study rats (Rattus norvegicus) Berkenhout, 1769 and triatomines (Meccus phyllosomus longipennis) (Usinger, 1939) were collected inside and outside human dwellings. Most rats (68.6%, n=312) and triatomines (68.7%, n=217) were collected along months of the hot season. Most rats (59.3%) were collected in peridomiciliary areas. From 312 examined rats, 71 (22.7%) were positive for T. cruzi on examination by Indirect Hemagglutination, which was confirmed by xenodiagnosis. From the 217 examined triatomines, 169 (77.9%) were infected by T. cruzi. The presence of infected rats and triatomines was highly related since on every studied human dwelling where infected triatomines were collected, infected rats were also found. Rats seem to constitute an important domiciliary and peridomiciliary reservoir for T. cruzi, furthering the risk of infection for human beings.

Ribavirin treatment of a patient with chronic hepatitis E. First case reported in Latin America.

We describe a clinical case of a kidney transplant patient who presented a sudden elevation of his liver function tests. Once we ruled out the most frequent causes of acute hepatitis, serum tests for Hepatitis E were performed. Hepatitis E virus RNA was detected in blood and stools. After six months the virus was still detected. Ribavirin treatment was initiated with normalization of the serum aminotransferases and sustained virology response was achieved.

A practice-based observational study on the use of micafungin in Surgical Critical Care Units.

INTRODUCTION: Echinocandins are first-line therapy in critically ill patients with invasive Candida infection (ICI). This study describes our experience with micafungin at Surgical Critical Care Units (SCCUs). METHODS: A multicenter, observational, retrospective study was performed (12 SCCUs) by reviewing all adult patients receiving 100 mg/24h micafungin for ≥72h during ad-mission (April 2011-July 2013). Patients were divided by ICI category (possible, probable + proven), 24h-SOFA (<7, ≥7) and outcome. RESULTS: 72 patients were included (29 possible, 13 probable, 30 proven ICI). Forty patients (55.6%) presented SOFA ≥7. Up to 78.0% patients were admitted after urgent surgery (64.3% with SOFA <7 vs. 90.3% with SOFA ≥7, p=0.016), and 84.7% presented septic shock. In 66.7% the site of infection was intraabdominal. Forty-nine isolates were recovered (51.0% C. albicans). Treatment was empirical (59.7%), microbiologically directed (19.4%), rescue therapy (15.3%), or anticipated therapy and prophylaxis (2.8% each). Empirical treatment was more frequent (p<0.001) in possible versus probable + proven ICI (86.2% vs. 41.9%). Treatment (median) was longer (p=0.002) in probable + proven versus possible ICI (13.0 vs. 8.0 days). Favorable response was 86.1%, without differences by group. Age, blood Candida isolation, rescue therapy, final MELD value and %MELD variation were significantly higher in patients with non-favorable response. In the multivariate analysis (R2=0.246, p<0.001) non-favorable response was associated with positive %MELD variations (OR=15.445, 95%CI= 2.529-94.308, p=0.003) and blood Candida isolation (OR=11.409, 95%CI=1.843-70.634, p=0.009). CONCLUSION: High favorable response was obtained, with blood Candida isolation associated with non-favorable response, in this series with high percentage of patients with intraabdominal ICI, septic shock and microbiological criteria for ICI.

A practice-based observational study on the use of micafungin in Surgical Critical Care Units / Estudio observacional basado en la práctica clínica sobre la utilización de micafungina en Unidades de Cuidados Críticos Quirúrgicos

Introducción. Las equinocandinas son tratamiento de primera línea en pacientes críticos con infección invasiva por Candida (IIC). Este estudio describe nuestra experiencia con micafungina en Unidades de Cuidados Críticos Quirúrgicos (UCCQs). Métodos. Se realizó un estudio multicéntrico, observacional y retrospectivo (12 UCCQs) revisando todos los pacientes adultos que recibieron 100 mg/24h micafungina durante ≥72h tras su admisión en la UCCQ (Abril 2011-Julio 2013). Los pacientes se dividieron según la categoría de IIC (posible, probable + probada), valor de SOFA (<7, >=7) y evolución. Resultados. Se incluyeron 72 pacientes (29 posible, 13 probable y 30 IIC probadas). Cuarenta pacientes (55,6%) presentaron SOFA ≥7. Un total de 78,0% pacientes fueron ingresados tras cirugía urgente (64,3% con SOFA <7 vs. 90,3% con SOFA ≥7, p=0,016) y un 84,7% presentó shock séptico. El 66,7% de pacientes presentaban infección intraabdominal. Se recuperaron 49 aislados (51,0% C. albicans). El tratamiento fue empírico (59,7%), dirigido microbiológicamente (19,4%), terapia de rescate (15,3%), o anticipado y profilaxis (2,8% cada uno). El tratamiento empírico fue más frecuente (p<0,001) en IIC posible versus probable + probada (86,2% vs. 41,9%). La duración del tratamiento (mediana) fue mayor (p=0,002) en IIC probable + probada que en IIC posible (13,0% vs. 8,0%). La respuesta clínica fue favorable en el 86,1% sin diferencias por grupo. La edad, el aislamiento de sangre, la terapia de rescate, el valor de MELD final y la variación de MELD fueron significativamente superiores en pacientes con respuesta clínica no favorable. En el análisis multivariado (R2 =0,246, p<0,001) la respuesta no favorable se asoció con variación positiva del MELD (OR=15,445, 95%IC= 2,529-94,308, p=0,003) y aislamiento de Candida en sangre (OR=11,409, 95%IC=1,843-70,634, p=0,009). Conclusión: Se obtuvo una alta tasa de respuesta favorable, con el aislamiento de Candida en sangre asociado con respuesta no favorable en esta serie de pacientes con alto porcentaje de IIC intraabdominal, shock séptico e IIC con criterios microbiológicos (AU)

Introduction. Echinocandins are first-line therapy in critically ill patients with invasive Candida infection (ICI). This study describes our experience with micafungin at Surgical Critical Care Units (SCCUs). Methods. A multicenter, observational, retrospective study was performed (12 SCCUs) by reviewing all adult patients receiving 100 mg/24h micafungin for ≥72h during admission (April 2011-July 2013). Patients were divided by ICI category (possible, probable + proven), 24h-SOFA (<7, ≥7) and outcome. Results. 72 patients were included (29 possible, 13 probable, 30 proven ICI). Forty patients (55.6%) presented SOFA ≥7. Up to 78.0% patients were admitted after urgent surgery (64.3% with SOFA <7 vs. 90.3% with SOFA ≥7, p=0.016), and 84.7% presented septic shock. In 66.7% the site of infection was intraabdominal. Forty-nine isolates were recovered (51.0% C. albicans). Treatment was empirical (59.7%), microbiologically directed (19.4%), rescue therapy (15.3%), or anticipated therapy and prophylaxis (2.8% each). Empirical treatment was more frequent (p<0.001) in possible versus probable + proven ICI (86.2% vs. 41.9%). Treatment (median) was longer (p=0.002) in probable + proven versus possible ICI (13.0 vs. 8.0 days). Favorable response was 86.1%, without differences by group. Age, blood Candida isolation, rescue therapy, final MELD value and %MELD variation were significantly higher in patients with non-favorable response. In the multivariate analysis (R2 =0.246, p<0.001) non-favorable response was associated with positive %MELD variations (OR=15.445, 95%CI= 2.529-94.308, p=0.003) and blood Candida isolation (OR=11.409, 95%CI=1.843-70.634, p=0.009) (AU)

A practice-based observational study identifying factors associated with the use of high-dose tigecycline in the treatment of secondary peritonitis in severely ill patients.

INTRODUCTION: Based on tigecycline linear pharmacokinetic/pharmacodynamics, dose increases have been advocated to maximise activity especially when severe infections with high bacterial load and/or multidrug resistance are suspected. This practice-based observational study explored factors associated with tigecycline administration (100 mg/12h, 200 mg loading dose) in severely ill patients with complicated intra-abdominal infection (cIAI) admitted to four Surgical Critical Care Units (SCCUs). METHODS: Medical records of all consecutive adult patients with cIAI and controlled infection source requiring surgery and admission for ≥ 48 h to SCCU were reviewed and divided into patients treated with a regimen including tigecycline (tigecycline group) and those that not (control group). A logistic regression model was performed using "tigecycline administration" (dependent variable) and variables showing differences (p ≤ 0.1) in bivariate analyses (independent variables). RESULTS: One hundred and twenty one patients were included. In the tigecycline group, higher percentage of patients (vs. controls) presented colon as surgical site (66.7% vs. 41.8%, p = 0.006), nosocomial infection (55.6% vs. 26.9%, p = 0.001), mechanical ventilation (48.1% vs. 28.4%, p = 0.025), chronic renal replacement therapy (40.7% vs. 19.4%, p =0.008), septic shock (72.2% vs. 46.3%, p = 0.004), and higher values of SAPS II (48.0 ± 15.0 vs. 39.6 ± 15.5, p = 0.003), SOFA at admission (7.0 ± 3.3 vs. 5.5 ± 3.7, p = 0.020), lactate-24h (2.5 ± 2.8 vs. 1.6 ± 0.9, p = 0.029) and CRP-72 h (207.4 ± 87.9 vs. 163.7 ± 76.8, p = 0.021). In the multivariate analysis (R2 = 0.187, p < 0.001) nosocomial infection (OR = 7.721; 95%CI = 2.193, 27.179; p = 0.001), colon as infection site (OR = 4.338; 95%CI = 1.432, 13.145; p = 0.009) and CRP-72 h (OR = 1.009 per-unit; 95%CI = 1.002, 1.016; p = 0.012) were associated with tigecycline administration. CONCLUSIONS: In severely ill patients with cIAI, high-dose tigecycline administration was associated with nosocomial origin of cIAI and colon as source infection site.

A practice-based observational study identifying factors associated with the use of high-dose tigecycline in the treatment of secondary peritonitis in severely ill patients

Introducción. Se han postulado incrementos en la dosis de tigeciclina basándose en su farmacocinética/farmacodinamia lineal, especialmente en infecciones graves con sospecha de alta carga bacteriana o/y multirresistencia. El presente estudio observacional basado en la práctica diaria explora los factores asociados con la administración de tigeciclina (100 mg/12h, 200 mg dosis de carga) en pacientes críticos con infección intraabdominal complicada (cIIA) ingresados en 4 Unidades de Cuidados Críticos Quirúrgicos (UCCQ). Métodos. Las historias clínicas de todos los pacientes adultos consecutivos con cIIA y foco de infección controlado que requerían cirugía e ingresaron en UCCQ durante ≥48h fueron revisadas y los pacientes fueron divididos en dos grupos: pacientes tratados con un régimen antibiótico que incluía tigeciclina (grupo tigeciclina) y aquellos que no (grupo control). Se realizó un modelo de regresión logística utilizando como variable dependiente la administración de tigeciclina y como independientes aquellas variables que mostraron diferencias (p≤0,1) en el análisis bivariado realizado. Resultados. Se incluyeron 121 pacientes. En el grupo tigeciclina, un mayor porcentaje de pacientes (vs. control) presentaban el colon como sitio quirúrgico (66,7% vs. 41,8%, p=0,006), infección nosocomial (55,6% vs. 26,9%, p=0,001), ventilación mecánica (48,1% vs. 28,4%, p=0,025), terapia renal sustitutoria (40,7% vs. 19,4%, p=0,008), shock séptico (72,2% vs. 46,3%, p=0,025) y valores más altos de SAPS II (48,0±15,0 vs. 39,6±15,5, p=0,003), SOFA al ingreso (7,0±3,3 vs. 5,5±3,7, p=0,020), lactato-24h (2,5±2,8 vs. 1,6±0,9, p=0,029) y PCR-72h (207,4±87,9 vs. 163,7±76,8, p=0,021). En el análisis multivariado (R2=0,187, p<0,001) la administración de tigeciclina se asoció con infección nosocomial (OR=7,721, 95%IC=2,193-27,179; p=0,001), colon como foco de infección (OR=4,338, 95%IC=1,432-13,145; p=0,009) y PCR-72h (OR=1,009 por unidad, 95%IC=1,002-1,016; p=0,012). Conclusiones. En pacientes críticos con cIIA, la administración de tigeciclina a dosis alta se asoció con el origen nosocomial de la infección y con el colon como foco de la misma (AU)

Introduction. Based on tigecycline linear pharmacokinetic/pharmacodynamics, dose increases have been advocated to maximise activity especially when severe infections with high bacterial load and/or multidrug resistance are suspected. This practice-based observational study explored factors associated with tigecycline administration (100 mg/12h, 200 mg loading dose) in severely ill patients with complicated intra-abdominal infection (cIAI) admitted to four Surgical Critical Care Units (SCCUs). Methods. Medical records of all consecutive adult patients with cIAI and controlled infection source requiring surgery and admission for ≥48h to SCCU were reviewed and divided into patients treated with a regimen including tigecycline (tigecycline group) and those that not (control group). A logistic regression model was performed using 'tigecycline administration' (dependent variable) and variables showing differences (p≤0.1) in bivariate analyses (independent variables). Results. One hundred and twenty one patients were included. In the tigecycline group, higher percentage of patients(vs. controls) presented colon as surgical site (66.7% vs. 41.8%, p=0.006), nosocomial infection (55.6% vs. 26.9%, p=0.001), mechanical ventilation (48.1% vs. 28.4%, p=0.025), chronic renal replacement therapy (40.7% vs. 19.4%, p=0.008), septic shock (72.2% vs. 46.3%, p=0.004), and higher values of SAPS II (48.0±15.0 vs. 39.6±15.5, p=0.003), SOFA at admission (7.0±3.3 vs. 5.5±3.7, p=0.020), lactate-24h (2.5±2.8 vs. 1.6±0.9, p=0.029) and CRP-72h (207.4±87.9 vs. 163.7±76.8, p=0.021). In the multivariate analysis (R2=0.187, p<0.001) nosocomial infection (OR=7.721; 95%CI=2.193, 27.179; p=0.001), colon as infection site (OR=4.338; 95%CI=1.432, 13.145; p=0.009) and CRP-72h (OR=1.009 per-unit; 95%CI=1.002, 1.016; p=0.012) were associated with tigecycline administration. Conclusions. In severely ill patients with cIAI, high-dose tigecycline administration was associated with nosocomial origin of cIAI and colon as source infection site (AU)

Procalcitonin-guided therapy may reduce length of antibiotic treatment in intensive care unit patients with secondary peritonitis: A multicenter retrospective study.

PURPOSE: Because procalcitonin (PCT) might be surrogate for antimicrobial discontinuation in general intensive care units (ICUs), this study explored its use for secondary peritonitis in 4 surgical ICUs (SICUs). METHODS: A retrospective study including all consecutive patients with secondary peritonitis, controlled infection source, requiring surgery, and at least 48-hour SICU admission was performed (June 2012-June 2013). Patients were divided following notations in medical records into PCT-guided (notation of PCT-based antibiotic discontinuation) and non-PCT-guided (no notation) groups. RESULTS: A total of 121 patients (52 PCT-guided, 69 non-PCT-guided) were included. No differences in clinical scores, biomarkers, or septic shock (30 [57.7%] PCT-guided vs 40 [58.0%] non-PCT-guided) were found. Length of intra-SICU (median, 5.0 days; both groups) or in-hospital (median, 20.0 vs 17.5 days) stay, and mortality intra-SICU (9.6% vs 13.0%), 28-day (15.4% vs 20.3%), or in-hospital (19.2% vs 29.0%) were not significantly different (PCT-guided vs non-PCT-guided). In septic shock patients, no mortality differences were found (PCT-guided vs non-PCT-guided): 16.7% vs 22.5% (intra-SICU), 26.7% vs 32.5% (28-day), and 33.3% vs 42.5% (in-hospital). Treatment was shorter in the PCT-guided group (5.1 ±2.1 vs 10.2 ± 3.7 days, P < .001), without differences between patients with and without septic shock. CONCLUSION: Procalcitonin guidance produced 50% reduction in antibiotic duration (P < .001, log-rank test).

Micafungin pharmacokinetic/pharmacodynamic adequacy for the treatment of invasive candidiasis in critically ill patients on continuous venovenous haemofiltration.

OBJECTIVES: To explore the pharmacokinetics (PK) and pharmacodynamics (PD) of micafungin in patients undergoing continuous venovenous haemofiltration (CVVH). PATIENTS AND METHODS: Ten patients receiving CVVH treated with 100 mg/day micafungin were included (April-December 2012). CVVH was performed using polyethersulphone or polysulphone haemofilters. Dialysis membranes were not changed on sampling days. On Days 1 and 2, blood samples from arterial pre-filter and venous post-filter ports and ultrafiltrate samples were collected at the start and end of the infusion and at 3, 5, 8, 18 and 24 h. Concentrations were determined using HPLC. Values for the area under the concentration-time curve (AUC0-24) were calculated. Monte Carlo simulations were performed using pre-filter and post-filter AUC0-24/MIC ratios on Days 1 and 2. The probability of target attainment (PTA) was calculated using AUC0-24/MIC cut-offs: 285 (C. parapsilosis), 3000 (all Candida spp.) and 5000 (non-parapsilosis Candida spp.). Cumulative fraction responses (CFRs) were calculated using EUCAST MIC distributions. RESULTS: Mean post-filter AUC0-24 (mg·h/L) values were higher than pre-filter values on Day 1 (83.31 ±â€Š15.87 versus 71.31 ±â€Š14.24; P = 0.008) and Day 2 (119.01 ±â€Š27.20 versus 104.54 ±â€Š21.23; P = 0.005). PTAs were ≥90% for MICs of 0.125 mg/L (cut-off = 285), 0.016 mg/L (cut-off = 3000) and 0.008 mg/L (cut-off = 5000) on Day 1, and for MICs of 0.25 mg/L (cut-off = 285) and 0.016 mg/L (cut-off = 3000 and 5000) on Day 2, without differences between pre- and post-filter values. On Day 2, CFRs >90% were obtained for C. albicans (cut-off = 3000 and 5000) and C. glabrata (cut-off = 3000), but not for C. parapsilosis. CONCLUSIONS: There was no removal of micafungin by CVVH or need for dose adjustment, and there was optimal PK/PD coverage for non-parapsilosis Candida and equivalence of pre- and post-filter PD.

Natural infection and distribution of triatomines (Hemiptera: Reduviidae) in the state of Querétaro, Mexico.

Chagas disease is present in Mexico but data on the presence of its vectors are not known for all the states. We conducted an epidemiological study to ascertain the presence of bedbugs in 23 communities of seven municipalities in the state of Querétaro, Mexico. Sampling was performed within and outside dwellings, using the technique of one person searching per hour per house. Four triatomine species were found: Triatoma mexicana (94%), Tri. dimidiata (3%), Tri. gerstaeckeri (2%) and Tri. pallidipennis (1%). Triatoma mexicana was found in six of the seven municipalities but has previously been found only in the state of Hidalgo, where it is considered the most important vector species of Trypanosoma cruzi. This is the first time that the presence of Tri. gerstaeckeri or Tri. dimidiata has been reported in the state of Querétaro. Tolimán municipality had the highest entomological indices: infestation index 73%; infection index 34.5%; crowding index 9.2%; density index 6.7%; and colonization index 20.6%. Although the prevalence and colonization indices were low, the infestation and infection indices indicate that different Triatoma species are becoming established in Querétaro. This work represents the first entomological study in this Mexican state and suggests that some triatomine vectors are extraordinarily mobile.

Continuous hemofiltration in hyperthermic septic shock patients.

BACKGROUND: Severe hyperthermia commonly accompanies septic shock. High body temperature in absence of infection activates the inflammatory response and is associated with a high mortality. Three years ago, our hypothesis that sustained fever is harmful in septic shock led us to the development of a protocol aiming at decreasing hyperthermia (>/=39.5 degrees C) by means of hemofiltration when the patients did not respond to antipyretics. We present a report of temperature and hemodynamic changes and the outcome of 19 consecutive hyperthermic septic shock patients with multiorgan system failure and compare them with a historical similar group of patients in whom hyperthermia was not treated with hemofiltration. METHODS: Depending on renal function, patients were treated with continuous low-flow hemofiltration (n = 8) or hemodiafiltration, (n = 11). Core temperature was registered every hour. A hemodynamic index (HI) was defined (mean arterial pressure to noradrenaline dose) and used during the first 24 hours to describe the patients' hemodynamic profile by means of its percent variation starting 6 hours before instituting the hemofiltration. RESULTS: The patients' temperature decreased linearly from 39.8 degrees C +/- 0.5 degrees C before hemofiltration to 37 degrees C +/- 1.2 degrees C after 24 hours of treatment (p < 0.001). The HI decreased significantly from -6 hours to the onset of hemofiltration (p = 0.002) and increased significantly after 24 hours (p = 0.008). Twenty-eight-day mortality was 32% (6 of 19) when compared with 100% (11 of 11) in the historical group (p < 0.001). CONCLUSIONS: Continuous low-flow hemofiltration decreased body temperature and vasopressor requirements in hyperthermic septic shock patients. The mortality was unexpectedly low.

Use of an iron superoxide dismutase excreted by Trypanosoma cruzi in the diagnosis of Chagas disease: seroprevalence in rural zones of the state of Queretaro, Mexico.

Four iron superoxide dismutase (SODI, SODII, SODIII, and SODIV) activities with pI values of 6.9, 6.8, 5.25, and 3.8, respectively, were isolated from epimastigote forms of the Maracay strain of Trypanosoma cruzi cultivated at 28 degrees C in Grace's medium supplemented with 10% heat-inactivated fetal bovine serum. The activity of SODe (pI 3.8), which coincides with that of SODIV, was detected in Grace's medium without serum in which T. cruzi epimastigotes were cultivated for 24 hours at 28 degrees C. SODe, which was excreted into the medium by the parasite, was immunogenic and antibodies to SODe were detected in serum to a dilution of 1:2,500 by Western blot. The role of SODe is related to the establishment of the parasite within the host, and its high immunogenicity and specificity make it a useful molecular marker in diagnosing infection with this parasite. To validate a Western blot result using SODe as a antigen fraction, 1,029 sera of individuals from 11 municipalities in the state of Queretaro, Mexico were analyzed. Sampling was done randomly and results were compared with those for the same sera with three conventional serologic methods: an enzyme-linked immunosorbent assay (ELISA), indirect hemagglutination (IHA), and an indirect immunofluorescence assay (IFA) to detect antibodies to T. cruzi SODe. Samples that were positive by these three techniques were also positive by the Western blot method. The seroprevalence values for SODe (8.16% by ELISA and Western blot) in Queretaro were considerably higher than those reported in regions of Mexico considered to be endemic for Chagas disease. These results support the use of SODe in the serodiagnosis of Chagas disease.

Acrylamide formation mechanism in heated foods.

Recent findings of a potential human carcinogen, acrylamide, in foods have focused research on the possible mechanisms of formation. We present a mechanism for the formation of acrylamide from the reaction of the amino acid asparagine and a carbonyl-containing compound at typical cooking temperatures. The mechanism involves formation of a Schiff base followed by decarboxylation and elimination of either ammonia or a substituted imine under heat to yield acrylamide. Isotope substitution studies and mass spectrometric analysis of heated model systems confirm the presence of key reaction intermediates. Further confirmation of this mechanism is accomplished through selective removal of asparagine with asparaginase that results in a reduced level of acrylamide in a selected heated food.

La información anestésica quirúrgica: su efecto sobre la ansiedad y el dolor de los pacientes toracotomizados / Information on surgery and anesthesia: its effect on anxiety and pain in thoracic surgery patients

Introducción: La cirugía es una experiencia estresante por una variedad de razones. Las condiciones de recuperación y la evolución del evento quirúrgico pueden variar en función de la situación emocional del paciente. Para muchos profesionales de la salud, la información acerca del proceso quirúrgico provocaría un beneficio emocional al paciente. Objetivo: El propósito de este estudio fue evaluar el efecto que ejerce la información estructurada y detallada de una cirugía de tórax en pacientes del Instituto Nacional de Enfermedades Respiratorias que son sometidos a ella. Método: A los pacientes se les aceptó mediante un consenso médico-quirúrgico para ser operados (toracotomía). Se les incluyó en el estudio bajo los siguientes criterios: alfabetas, edad entre 18 a 65 años y de cualquier sexo; se les aplicaron los instrumentos de medición de su situación emocional: escala HAD (mide ansiedad y depresión), IDARE (mide ansiedad), una escala análoga visual para ansiedad y otra para dolor (EVA); una escala prequirúrgica (APAIS) y un cuestionario de personalidad (EPQ). Los pacientes fueron asignados aleatoriamente para recibir, o no, información por parte de dos investigadoras ajenas a la evaluación emocional; 24 horas después de la cirugía se les aplicaron los instrumentos para medir ansiedad y dolor, el IDARE y EVA y una semana después el HAD. Resultados: De 33 pacientes, 14 recibieron la maniobra experimental (caso) y 19 la control. Los resultados arrojan algunas diferencias entre los grupos, pero no son estadísticamente significativas. Parece que además de la información del proceso quirúrgico, se requieren de otras intervenciones para modificar la situación emocional del paciente.