Innovative Integration of Arrayan (Luma apiculata) Extracts in Chitosan Coating for Fresh Strawberry Preservation.

Strawberries are a rich source of vitamins and antioxidants, among other nutrients, but they are highly susceptible to mechanical injuries, dehydration, and microbial spoilage, and thus have a limited post-harvest shelf-life. Bioactive edible coatings have been studied to decrease or prevent these damages. In this study, ethanolic extracts of Arrayan (Luma apiculata), a traditional berry from the south of Chile, were used to enrich a chitosan-based edible film and coat fresh strawberries. A long-term storage (10 °C) study was conducted to determine the strawberries' weight loss, microbial stability, fruit firmness impact, and antioxidant activity. Later, a sensory panel was conducted to determine overall consumer acceptance. Our results show that the bioactive coating inhibited the growth of different pathogenic bacteria and spoilage yeast. In the stored strawberries, the weight loss was significantly lower when the bioactive coating was applied, and the samples' firmness did not change significantly over time. Microbial growth in the treated strawberries was also lower than in the control ones. As expected, the antioxidant activity in the coated strawberries was higher because of the Arrayan extract, which has high antioxidant activity. Regarding sensory qualities, the covered strawberries did not show significant differences from the uncoated samples, with an overall acceptance of 7.64 on a 9-point scale. To our knowledge, this is the first time an edible coating enriched with Arrayan extracts has been reported as able to prevent strawberries' decay and spoilage.

Relación de las Enfermedades Crónicas no Transmisibles y Ejercicio Físico en la Población Chilena entre los años 2015-2016 / Risk of Retention of Secretions in Patients with Invasive Mechanical Ventilation

Introducción. Las prevalencias de la inactividad física, el sedentarismo y el sobrepeso y obesidad han aumentado sus índices durante los últimos años en Chile, lo que conlleva al desarrollo y aparición de diversas enfermedades crónicas no transmisibles, como por ejemplo, hipertensión arterial, diabetes mellitus e inclusive enfermedades respiratorias, las cuales repercuten negativamente en la población y deterioran la calidad de vida de las personas, independientemente el sexo y el rango etario. El ejercicio físico es una de las principales herramientas utilizadas por diversos profesionales de la salud como método de prevención y tratamiento en la población afectada, inclusive representa una alternativa de menor costo. Objetivo. Relacionar el ejercicio físico de alta y mediana intensidad con las enfermedades crónicas no transmisibles en personas mayores a 18 años residentes en Chile durante el periodo 2015-2016. Métodos. Análisis cuantitativo, descriptivo, transversal y retrospectivo de base secundaria ENCAVI 2015-2016, de residentes en Chile mayores de 18 años y con al menos una de las siguientes condiciones de salud: Hipertensión arterial, Diabetes Mellitus y enfermedades respiratorias crónicas no transmisibles. Resultados. Todas las variables presentan relaciones significativas (p<0,005) (HTA, DM, enfermedades respiratorias, edad, horas sentado, ejercicio físico de moderada y alta intensidad. Sin embargo, las variables de ejercicio físico moderada intensidad y enfermedades respiratorias (p=0,578) y las variables de sexo y horas sentado (p=0,005) no presentan relación significativa. Discusión. El ejercicio físico de moderada intensidad es el que tiene mejor respuesta ante las diferentes patologías según diferentes autores, por otro lado, en la recopilación de datos podemos encontrar que este tipo de ejercicio es efectivo en la Diabetes Mellitus. Conclusiones. Según los datos analizados, mientras mayor frecuencia de ejercicio físico de alta intensidad (en días) y ejercicio físico de moderada intensidad (en horas) se realice durante los últimos días de la semana, los diagnósticos de las enfermedades crónicas no transmisibles (HTA, DM) y enfermedades respiratorias se verán controladas, mientras que, cuando existe menor frecuencia del ejercicio físico realizado durante los últimos días de la semana, tiende a existir mayor diagnóstico.

Background. The prevalence of physical inactivity, sedentary lifestyle, and overweight and obesity have increased their rates in recent years in Chile, which leads to the development and appearance of various chronic non-communicable diseases, such as for example, arterial hypertension, diabetes mellitus and even respiratory diseases, which have a negative impact on the population and deteriorate the quality of life of people, regardless of gender and age range (7). Physical exercise is one of the main tools used by various health professionals as a method of prevention and treatment in the affected population, even representing a lower cost alternative. Objetive. To relate high and medium intensity physical exercise with chronic non-communicable diseases in people over 18 years of age residing in Chile during the period 2015-2016. Methods. Quantitative, descriptive, cross-sectional and retrospective analysis of the ENCAVI 2015-2016 secondary base of residents in Chile over 18 years of age and with at least one of the following health conditions: High blood pressure, Diabetes Mellitus and chronic non-communicable respiratory diseases. Results. All the variables present significant relationships (p<0.005) (HTN, DM, respiratory diseases, age, hours sitting, moderate and high intensity physical exercise. However, the variables of moderate intensity physical exercise and respiratory diseases (p=0.578) and the variables of sex and sitting hours (p=0.005) do not present a significant relationship. Discussion. Moderate intensity physical exercise is the one that has the best response to different pathologies according to different authors, on the other hand, in data collection we can found that this type of exercise is effective in Diabetes Mellitus. Conclusions. According to the data analyzed, the greater the frequency of high-intensity physical exercise (in days) and moderate-intensity physical exercise (in hours) performed during the last days of the week, the diagnoses of chronic non-communicable diseases (HTN, DM) and respiratory diseases will be controlled, while, when there is less frequency of physical exercise carried out during the last days of the week, there tends to be a greater diagnosis.

Determination of the Dissolution/Permeation and Apparent Solubility for Microencapsulated Emamectin Benzoate Using In Vitro and Ex Vivo Salmo salar Intestine Membranes.

In this work, two microencapsulation techniques were used to protect and improve the absorption of emamectin benzoate (EB), which is an antiparasitic drug used to control Caligus rogercresseyi. EB has a low aqueous solubility, which affects its absorption in the intestine of Salmo salar. Microparticles were produced by spray drying and ionic gelation, using Soluplus® (EB−SOL) and sodium alginate (EB−ALG) as polymers, respectively. Studies were conducted on dissolution/permeation, apparent permeability (Papp), apparent solubility (Sapp), and absorption using synthetic and biological membranes. Based on these results, the amount of EB in the microparticles needed to achieve a therapeutic dose was estimated. The EB−ALG microparticles outperformed both EB−SOL and free EB, for all parameters analyzed. The results show values of 0.45 mg/mL (80.2%) for dissolution/permeation, a Papp of 6.2 mg/mL in RS−L, an absorption of 7.3% in RS, and a Sapp of 53.1% in EM medium. The EB−ALG microparticles decrease the therapeutic dose necessary to control the parasite, with values of 3.0−2 mg/mL and 1.1−2 mg/mL for EB in EM and RS, respectively. The Korsmeyer−Peppas kinetic model was the best model to fit the EB−ALG and EB−SOL dissolution/permeation experiments. In addition, some of our experimental results using synthetic membranes are similar to those obtained with biological membranes, which suggests that, for some parameters, it is possible to replace biological membranes with synthetic membranes. The encapsulation of EB by ionic gelation shows it is a promising formulation to increase the absorption of the poorly soluble drug. In contrast, the spray-dried microparticles produced using Soluplus® result in even less dissolution/permeation than free EB, so the technique cannot be used to improve the solubility of EB.

Evaluation of Indigenous Candida oleophila and Candida boidinii in Monoculture and Sequential Fermentations: Impact on Ethanol Reduction and Chemical Profile in Chilean Sauvignon Blanc Wines.

The study of non-Saccharomyces yeasts in wine fermentations allows the exploration of new alternatives for the reduction of ethanol in wines. The objective of this work was to evaluate the fermentation capacity of two indigenous Candida yeasts (C. oleophila and C. boidinii) in monoculture and sequential fermentations (laboratory and microvinification scale) to produce Chilean Sauvignon Blanc wine. Fermentations were monitored by the determination of ethanol, glycerol, organic acids, and residual sugars. The results indicated that at the laboratory scale for both the monoculture and sequential fermentations it was possible to reduce the ethanol concentration on 0.77% v/v (monoculture) and 1.5% v/v (sequential) for C. oleophila and 0.50% v/v (monoculture) and 0.04% v/v (sequential) for C. boidinii compared to S. cerevisiae (12.87% v/v). Higher glycerol concentrations were produced in monoculture than sequential fermentations (C. oleophila: 9.47 g/L and C. boidinii 10.97 g/L). For microvinifications, the monoculture and sequential fermentations with C. boidinii managed to reduce ethanol content by 0.17% v/v and 0.54% v/v, respectively, over the S. cerevisiae control (13.74% v/v). In the case of C. oleophila, the reduction was only observed in sequential fermentations with 0.62% v/v. Interestingly, grapes with higher sugar concentration resulted in wines with lees ethanol concentrations. This might be associated to the use of C. oleophila (13.12% v/v) and C. boidinii (13.20% v/v) in sequential fermentations microvinification scale.

Native Yeasts and Lactic Acid Bacteria Isolated from Spontaneous Fermentation of Seven Grape Cultivars from the Maule Region (Chile).

Grapes are a source of native yeasts and lactic acid bacteria (LAB); however, the microbial make up is dependent on the grape cultivar and the regional growth conditions. Therefore, the aim of this study was to characterize the yeast and LAB in seven grape cultivars cultivated in Chile. Grape juices were fermented at 25 °C for 7 days. Samples were collected to analyze sugar, organic acids, and ethanol. Microbial evolution was measured with culture-dependent and molecular approaches. Then, a native isolated Candida oleophila was selected for further sequential fermentations with Saccharomyces cerevisiae. The grape cultivars in the Maule showed a diversity of non-Saccharomyces yeasts, with a greater diversity observed at the beginning of the fermentation. However, species from the Hansenasporia, Metschnikowia, Torulaspora, Lachancea, and Candida genera were detected after 7 days, suggesting tolerance to environments rich in ethanol, capability may be associated to the terroir studied, which is characterized by torrid weather and antique and traditional vineyards. The alcoholic fermentation negatively impacted the LAB population, and after 7 days only Leuconostoc mesenteroides was isolated. In the sequential fermentations, C. oleophila was able to produce fermented grape juices with <1.5 g/L glucose, 12.5% (v/v) alcohol, and low concentrations of malic (<1.00 g/L) and succinic (2.05 g/L) acids, while acetic acid reached values >0.3 (g/L). To our knowledge this is the first time C. oleophila has been reported as a potential starter culture for wine production. However, more studies are necessary to fully characterize the potential of C. oleophila on wine attributes.

Thyme essential oil loaded microspheres for fish fungal infection: microstructure, in vitro dynamic release and antifungal activity.

AIMS: Evaluate the effect of varying the droplet size of microspheres charged with thyme essential oil (TEO-MS) on their swelling (Sw), release rate (%RR) and in vitro antifungal activity against Saprolegnia sp. METHODS: TEO-MS obtained by ionic gelation were characterised through SEM microscopy and X-ray microtomography. Their Sw and RR% were evaluated at simulated fish-gastrointestinal conditions using gravimetric and spectrophotometric techniques. RESULTS: For all evaluated droplet sizes (p ≥ 0.05), TEO was heterogeneously distributed inside of the MS and TEO-MS experimented agglomeration and sphericity loss after the drying process. Under gastric conditions, the acid pH (2.9) limited the Sw (50-100%) of TEO-MS, generating a low RR% (14-18%). Contrary, the slightly alkaline intestinal pH (8.1) favoured the Sw (∼3.2 to 3.8 times) and therefore the RR% (42-63%). CONCLUSIONS: TEO-MS (5-100 mg/mL) presented antifungal capacity onto Saprolegnia sp. after the simulated fish digestion, being the small droplet size once the most effective.

Large Retropharyngeal Abscesses in an Immunocompetent Adult Patient with Disseminated Tuberculosis.

BACKGROUND The retropharyngeal abscess is a rare presentation of head and neck tuberculosis. The pathogenesis of the abscess formation in the retropharyngeal space in the adult is controversial. CASE REPORT We report a case of large retropharyngeal abscesses in a 46-year-old man with disseminated tuberculosis. The patient had severe progressive dysphagia, weight loss, and a slowly enlarging bilateral cervical mass during a period of three months. His posterior pharynx wall was bulging and red, and both tonsils were enlarged and congested. The neck had an abscess of 5 cm in diameter that was firm, tender, and warm along the left sternocleidomastoid muscle. Palpable bilateral lymphadenitis was detected in the submandibular, cervical, axillary, and inguinal regions. A computed tomographic (CT) scan of the neck revealed large bilobulated retropharyngeal abscesses. A liver ultrasound showed multiple hypoechoic lesions. A Ziehl-Neelsen smear for acid-fast bacilli was positive from different abscess samples, and mycobacterial cultures subsequently yielded Mycobacterium tuberculosis. Antituberculous therapy was begun and the retropharyngeal abscesses were aspirated by external incision with complete drainage and relief of symptoms. CONCLUSIONS Large retropharyngeal abscess is a rare entity in which Mycobacterium tuberculosis etiology should be considered, especially in endemic countries, and the diagnosis may be difficult because symptoms and signs are influenced by abscess size and time of onset, or if the etiology is not suspected.

Development of alginate microspheres containing thyme essential oil using ionic gelation.

Essential oils are a good antimicrobial and antioxidant agent alternative in human or animal feed. However, their direct use has several disadvantages such as volatilization or oxidation. The development of essential oil microspheres may help to avoid these problems. The objective of the present research was to microencapsulate thyme essential oil by generating emulsions with different dispersion degrees. The emulsions were encapsulated in calcium-alginate microspheres by ionic gelation. The microspheres were evaluated regarding size, shape, encapsulation efficiency, loading capacity and antimicrobial properties. The results indicate that encapsulation efficiency and loading capacity are dependent on concentration and degree of dispersion. The best encapsulation conditions were obtained at 2% v/v of thyme essential oil with a high dispersion degree (18,000rpm/5min), which was achieved with an efficiency of 85%. Finally, the microspheres obtained showed significant antimicrobial effect, especially in gram-positive bacteria.

Clinical course of diabetic ketoacidosis in hypertriglyceridemic pancreatitis.

OBJECTIVES: Hypertriglyceridemic pancreatitis (HP) is an uncommon condition accounting for 1% to 4% of cases of acute pancreatitis, mostly associated with poor glycemic control. Diabetic ketoacidosis (DKA) may complicate the clinical course of HP. Our objective was to identify clinical and demographic differences between HP and DKA patients compared with those without DKA. METHODS: Fifty-five patients with HP were included. Diabetic ketoacidosis was diagnosed in 8 patients. We analyzed the severity, hospital stay, delay in oral intake, duration of insulin infusion, complete blood cell count, and triglyceride levels. RESULTS: Diabetic ketoacidosis was associated with a more severe HP. There were no differences in hospital stay, delay in oral intake, or duration of insulin treatment in both groups. Serum amylase, lipase, and triglyceride levels were similar. Previous diagnosis of diabetes mellitus, higher Ranson and APACHE II scores, and higher serum glucose level at admission were the only predictive risk factors for DKA and HP. CONCLUSIONS: Coexistence of DKA does not modify the clinical course of HP, although a more severe episode of HP in DKA patients. Diabetic ketoacidosis was associated with higher insulin doses, without impact in triglyceride levels. Diabetic ketoacidosis and HP should be considered when a previous diagnosis of diabetes mellitus and a severe HP are present.

Seguridad y eficacia del remifentanilo por vía intravenosa mediante un sistema de analgesia controlada por la paciente durante el trabajo por parto / Safety and efficacy of intravenous remifentanil by a patient controlled analgesia system during labor

Objetivo: Determinar la eficacia y seguridad del uso de remifentanilo por vía intravenosa, mediante un sistema de analgesia controlada por la paciente (ACP), durante el trabajo de parto. Material y métodos: Estudio descriptivo, longitudinal y prospectivo realizado en 30 gestantes en trabajo de parto con indicación de analgesia del Hospital Nacional Arzobispo Loayza. Se evaluó la eficacia del método a través de los niveles de analgesia y sedación durante el procedimiento, y una encuesta de satisfacción en el postoperatorio. Se valoró la seguridad de la técnica mediante el reporte de efectos adversos en la madre y el bienestar fetal por medio del registro cardiotocográfico, Apgar al minuto y a los 5 minutos, pH de arteria y vena de cordón umbilical, y un test de valoración de la capacidad adaptativa y neurológica del recién nacido a la 24 horas. Resultados: La dosis total de remifentanilo fue de 1,065 más menos 278 microgramos. El grado de analgesia alcanzado por las pacientes fue aceptable, con la reducción más importante de dolor y demandas de analgesia no satisfechas después de la primera hora. El nivel de sedación se mantuvo estable hasta el final del parto, con un elevado nivel de satisfacción de las pacientes al ser encuestadas en el postparto. Se observaron efectos adversos maternos, como náuseas en 5 pacientes (16.7%), vómitos y prurito en 2 pacientes (6.7%). Los parámetros de monitorización materno-fetal se mantuvieron dentro de la normalidad. La vitalidad de los recién nacidos evaluada mediante el test de Apgar, el pH de sangre venosa y arterial de cordón, y el test neurológico fueron óptimos en el momento del parto. Conclusiones: El empleo del remifentanilo intravenoso mediante la técnica de ACP es una técnica eficaz, segura puede constituir una alternativa aceptable y muy interesante en el manejo analgésico de las pacientes en labor de parto.

Objective: To determine the efficacy and safety of intravenously remifentanil by a patient-controlled analgesia (PCA) system during labor. Material and methods: A descriptive, longitudinal and prospective study in 30 pregnant women in labor with indication of labor analgesia of the Hospital Nacional Arzobispo Loayza. The efficacy of the method was evaluated by analgesia and sedation levels during the procedure and satisfaction surveys postoperatively. The safety of the technique was evaluated by recording adverse maternal reactions and fetal well-being by cardiotocography, Apgar at one minute and 5 minutes, pH of artery and vein of the umbilical cord, an a test for assessing the neurologic and adaptive capacity of the newborn at 24 hours. Results: The total dose of remifentanil was 1.065 more less 278 micrograms. The analgesia level achieved by the patients was acceptable, with the largest reduction of pain and unmet demands for analgesia after the first hour. The sedation level remained stable until the end of labor, with a high level of patient satisfaction when surveyed at the postpartum. Maternal adverse effects including nausea in patients (16.7%), vomiting and pruritus in 2 patients (6.7%). The parameters of maternal and fetal monitoring were within normal limits. The vitality of newborns assessed by Apgar score, pH of venous blood and cord blood, and neurological test were optimal at the time of delivery. Conclusion: The use of intravenous remifentanil by PCA technique is effective, safe and can be an acceptable and very interesting alternative in the analgesic management of patients in labor.

Seasonal variation of enteropathogens in infants and preschoolers with acute diarrhea in western Mexico.

The present study estimates the prevalence of some enteropathogens in infants and preschoolers with acute diarrhea. From 2006 to 2007, 5459 consecutive stool samples were evaluated. Cryptosporidium parvum was the parasite identified with the higher frequency (5.1%), followed by Giardia lamblia (1.2%). Campylobacter jejuni was isolated in 858 cases (15.7%) and was the most frequent enteropathogen overall. The rates of C parvum, Shigella, and Salmonella were higher in the summer. Rotavirus had the expected winter peak and it was the third enteropathogen because of its frequency. Overall frequency of stool-reducing substances was 15.6% and was associated with a rotavirus-positive test.

Serotypes and susceptibility of Streptococcus pneumoniae strains isolated from children in Mexico.

OBJECTIVE: To identify serotypes and susceptibility of S. pneumoniae strains from 48 children with invasive infections and 50 carriers. MATERIAL AND METHODS: Typing was performed by the Quellung reaction and susceptibility by Kirby-Bauer and Etest according to CLSI standards. RESULTS: Of 31 meningeal strains, serotypes 19F, 3, 6B, 14 and 23F were predominant. Resistance to penicillin and STX was 16 and 58%, respectively; of 17 invasive non-meningeal strains, serotypes 19F and 3 were predominant and resistance to penicillin and SXT was 0 and 82%, respectively; of carrier strains, serotypes 6A, 6B, 19F and 23F were predominant. CONCLUSIONS: A 10-valent conjugate vaccine could offer a better coverage for meningeal strains.

Serotypes and susceptibility of Streptococcus pneumoniae strains isolated from children in Mexico / Serotipos y susceptibilidad de cepas de Streptococcus pneumoniae aisladas de niños en México

Objective. To identify serotypes and susceptibility of S. pneumoniae strains from 48 children with invasive infections and 50 carriers. Material and Methods. Typing was performed by the Quellung reaction and susceptibility by Kirby-Bauer and Etest according to CLSI standards. Results. Of 31 meningeal strains, serotypes 19F, 3, 6B, 14 and 23F were predominant. Resistance to penicillin and STX was 16 and 58 percent, respectively; of 17 invasive non-meningeal strains, serotypes 19F and 3 were predominant and resistance to penicillin and SXT was 0 and 82 percent, respectively; of carrier strains, serotypes 6A, 6B, 19F and 23F were predominant. Conclusions. A 10-valent conjugate vaccine could offer a better coverage for meningeal strains.

Objetivo. Identificar serotipos y susceptibilidad en cepas aisladas de 48 niños con infecciones invasivas y de 50 portadores. Material y métodos. Serotipificación mediante reacción de Quellung y susceptibilidad mediante Kirby-Bauer y E-test. Resultados. De 31 cepas meníngeas, predominaron serotipos 19F, 3, 6B, 14 y 23F y la resistencia a penicilina (P) y trimetoprim-sulfametoxazol (SXT) fue de 16 y 58 por ciento. En 17 cepas invasivas no meníngeas, predominaron serotipos 19F y 3 y la resistencia a P y SXT fue de 0 y 82 por ciento, en cada caso. En portadores predominaron serotipos 6A, 6B, 19F y 23F. Conclusiones. La resistencia es similar a otros informes. La vacuna conjugada 10-valente podría ofrecer mejor cobertura para serotipos asociados a meningitis.

Molecular analysis of hepatitis B virus isolates in Mexico: predominant circulation of hepatitis B virus genotype H.

AIM: To determine the genotypes in Mexican hepatitis B virus (HBV) isolates and characterize their precore and core promoter mutations. METHODS: Forty-nine HBV isolates of Mexico obtained from sera of 15 hepatitis patients, 6 hemodialysis patients, 20 men seeking HIV testing, and 8 AIDS patients were analyzed. HBV isolates were amplified by PCR, and genotyped by line probe assay (INNO-LiPA HBV Genotyping; INNOGENETICS N V, Ghent, Belgium). HBV genotype confirmation was performed by DNA sequencing part of the sAg region. Precore and core promoter mutation characterization was performed by line probe assay (INNO-LiPA HBV PreCore; INNOGENETICS N V, Ghent, Belgium). RESULTS: Overall, HBV genotype H was found in 37 (75.5%) out of the 49 isolates studied. HBV genotypes G, A, and D were found in 5 (10.2%), 4 (8.2%), and 3 (6.1%) isolates, respectively. HBV genotype H was predominant in isolates from hemodialysis patients (100%), hepatitis patients (80%), and men seeking HIV testing (75%), and accounted for half of infections in AIDS patients (50%). Six (12.2%) out of the 49 HBV isolates showed both wild type and mutant populations at precore codon 28. These mixed wild type and precore mutant populations were observed in one HBV genotype A isolate and in all HBV genotype G isolates. A dual variant core promoter mutation was observed in 1 (2%) of the isolates, which was genotype H. CONCLUSION: HBV genotype H is highly predominant in HBV isolates of Mexico followed by genotypes G, A and D. A low frequency of precore and core promoter mutations is observed in HBV Mexican isolates.

Genotypic resistance to lamivudine among hepatitis B virus isolates in Mexico.

BACKGROUND: Drug resistance of hepatitis B virus (HBV) is an increasing clinical problem. Resistance to lamivudine in HBV isolates in Mexico has been poorly explored. OBJECTIVES: To characterize the mutation patterns associated with genotypic resistance to lamivudine and their prevalence among HBV isolates in Mexico. MATERIAL AND METHODS: Thirty-nine Mexican HBV isolates were analysed by PCR and line probe assay for detection of genetic variants in the polymerase open reading frame domains B and C (INNO-LiPA HBV DR; INNOGENETICS N. V., Ghent, Belgium). This assay detects wild-type and mutations at codons 180, 204 and 207 of the HBV polymerase gene, and at codon positions 171, 172, 195, 196, 198 and 199 of the HBV surface antigen (HBsAg). HBV isolates were obtained from HBsAg-positive serum samples of 15 chronic hepatitis patients, two haemodialysis patients with chronic HBV carriage, 20 men found positive for HBsAg when seeking HIV testing and two AIDS patients with chronic HBV infection. None of the participants had received antiviral therapy. RESULTS: Overall, HBV wild-type was found in 37 (94.9%) out of the 39 isolates studied. Two (5.1%) out of the 39 isolates showed mixed wild-type and mutant populations. These mutations occurred in isolates from one hepatitis patient and one haemodialysis patient. The isolate from the hepatitis patient showed a double mutation at codon positions 180 (L180M) and 204 (M204V), thus a 2.6% prevalence of genotypic resistance to lamivudine was found. The isolate from the haemodialysis patient showed a single mutation at codon position 180 (L180M). The two HBV mutant isolates were further analysed for genotype and both isolates were genotype H. CONCLUSIONS: HBV genotypic resistance to lamivudine exists in Mexican isolates. The results highlight the importance of testing for HBV resistance before treatment and have implications for a more rational use of drugs.

Changing trends in prevalence, morbidity, and lethality in persistent diarrhea of infancy during the last decade in Mexico.

BACKGROUND: Persistent diarrhea (PD) of infancy has incurred high morbidity and lethality. However, decrease in its prevalence, morbidity, and lethality appeared to occur progressively throughout the last decade of the twentieth century. Our objective in this study was to compare prevalence, lethality, and morbidity of infants and children with PD managed in a pediatric referral hospital. METHODS: We conducted a comparative cross-sectional study. A total of 546 patients with PD managed during three different periods (1988-1991, 1993-1994, and 1997-1999) were described and analyzed. Prevalence x 100 admissions, prevalence rates of nutritional status, sepsis, pneumatosis intestinalis, carbohydrate and protein intolerance, and lethality were calculated. We used Student t and chi2 tests (alpha = 0.05). RESULTS: Mean age on admission was 13.8 +/- 24.3 months; 296 (54.2%) patients were males. Prevalence of admissions for PD decreased gradually from 31.7 to 13.8%; rates of lethality and mortality remained unchanged. Malnutrition had high prevalence throughout the three periods evaluated. Rate of carbohydrate intolerance diminished but protein intolerance increased; proportion of pneumatosis intestinalis and bowel perforation did not change. Isolation of Salmonella spp. and small bowel bacterial overgrowth decreased significantly from the 1988-1991 series when compared with later series. CONCLUSIONS: Although these observations were made at a pediatric referral hospital, they may suggest that prevalence of PD is diminishing. However, its lethality and mortality rates remain unchanged. Malnutrition persists as a relevant associated factor. Decrease of carbohydrate intolerance and increase in protein intolerance rates resemble rates of children with PD of developed countries. These observations may reflect an epidemiologic transition of PD in Mexico.

Hepatitis C virus: prevalence and routes of infection among blood donors of West Mexico.

In Latin America few studies have explored frequency and risk factors predicting hepatitis C virus (HCV) infection in blood donors. In this study we determined the prevalence of HCV infection in blood donors from West Mexico. Potential risk factors, clinical, histological and virologic characteristics presented in this group were also evaluated. METHODS: HCV antibodies were evaluated in 57108 blood donors with commercial second-generation enzyme immunoassays. Positive results were confirmed by a recombinant immunoblot assay. Repeatedly seropositive donors were further studied for risk factors, history for hepatitis, hepatic enzymes (aspartate aminotransferase and alanine aminotransferase (AST and ALT)), liver histology and hepatitis C virus-ribonucleic acid (HCV-RNA) detection. RESULTS: A total of 499 blood donors were initially tested positive doubtful for antibodies to HCV Ab (0.8%). While there was no difference in HCV prevalence with respect to age or gender, the most frequent risk factors identified were transfusion (42%), household exposure (14.8%), multiple sex partner (6.8%) and intranasal cocaine use (2.3%). Also, we found that from a subgroup of donors tested for histological analysis, 19% presented abnormal ALT levels and 90% showed abnormal liver histology. No correlation was found between abnormal ALT levels and the presence of HCV-RNA in serum. CONCLUSION: These results demonstrate a low prevalence (0.8%) of HCV infection among Western Mexican blood donors, which was comparable to those established for Western countries, but in contrast in our study the most frequent risk factor continues being transfusion followed by household exposure.

[Utility of studying feces for the diagnosis and management of infants and preschool children with acute diarrhea]. / Utilidad del estudio de las heces para el diagnóstico y manejo de lactantes y prescolares con diarrea aguda.

OBJECTIVE: To analyze the results of a stool work-up protocol in a series of infants and preschoolers with acute diarrhea. MATERIAL AND METHODS: A cross-sectional descriptive study was conducted between April 1999 and March 2000, among 288 children seen at a pediatric office in Guadalajara, Mexico. The mean age (+/-/SD) was 23.1 +/- 13.9 months; 43% were females. Data were collected on demographic and clinical characteristics. The stool work-up consisted of fresh smear and methylene blue and Kinyoun smears, as well as determination of pH and reducing substances. Stool culture was performed in samples with > or = 3 leukocytes/microscopic field and rotavirus antigen detection only in selected cases. Data were analyzed using descriptive statistics, chi 2, odds ratios, and 95% confidence intervals. RESULTS: Enterophatogens (%) identified were: rotavirus 47.1, Campylobacter jejuni 27.4, Salmonella spp. 5.1, Shigella spp. 4.3, Cryptosporidium parvum 2.8, Giardia lamblia 2.4, Blastocystis hominis 1.4, Entamoeba histolytica 0.7. An OR of 5.7 was obtained for isolation of enteroinvasive bacteria in the presence of fecal leukocytes. Lactose intolerance was detected in 19.1%. The frequencies of rotavirus antigen identification and lactose intolerance were significantly higher in infants; the OR for lactose intolerance in infants with rotavirus was 21. Mucus and blood in the stools were associated to enteroinvasive bacteria and Cryptosporidium parvum. CONCLUSIONS: The current stool work-up protocol allowed the identification of enteropathogenic parasites, rotavirus and lactose intolerance in a short period of time. Leukocytes in stools were associated to the isolation of enteroinvasive bacteria. The frequency of agents associated to diarrheal disease was similar to that from other national studies. This stool work-up protocol could be useful as a tool to limit the unnecessary prescription of drugs and to follow universal recommendations for dietary management of these patients. The English version of this paper is available at: http://www.insp.mx/salud/index.html.

Utilidad del estudio de las heces para el diagnóstico y manejo de lactantes y prescolares con diarrea aguda / Utility of studying feces for the diagnosis and management of infants and preschool children with acute diarrhea

OBJECTIVE: To analyze the results of a stool work-up protocol in a series of infants and preschoolers with acute diarrhea. MATERIAL AND METHODS: A cross-sectional descriptive study was conducted between April 1999 and March 2000, among 288 children seen at a pediatric office in Guadalajara, Mexico. The mean age (+/-/SD) was 23.1 +/- 13.9 months; 43 were females. Data were collected on demographic and clinical characteristics. The stool work-up consisted of fresh smear and methylene blue and Kinyoun smears, as well as determination of pH and reducing substances. Stool culture was performed in samples with > or = 3 leukocytes/microscopic field and rotavirus antigen detection only in selected cases. Data were analyzed using descriptive statistics, chi 2, odds ratios, and 95 confidence intervals. RESULTS: Enterophatogens () identified were: rotavirus 47.1, Campylobacter jejuni 27.4, Salmonella spp. 5.1, Shigella spp. 4.3, Cryptosporidium parvum 2.8, Giardia lamblia 2.4, Blastocystis hominis 1.4, Entamoeba histolytica 0.7. An OR of 5.7 was obtained for isolation of enteroinvasive bacteria in the presence of fecal leukocytes. Lactose intolerance was detected in 19.1. The frequencies of rotavirus antigen identification and lactose intolerance were significantly higher in infants; the OR for lactose intolerance in infants with rotavirus was 21. Mucus and blood in the stools were associated to enteroinvasive bacteria and Cryptosporidium parvum. CONCLUSIONS: The current stool work-up protocol allowed the identification of enteropathogenic parasites, rotavirus and lactose intolerance in a short period of time. Leukocytes in stools were associated to the isolation of enteroinvasive bacteria. The frequency of agents associated to diarrheal disease was similar to that from other national studies. This stool work-up protocol could be useful as a tool to limit the unnecessary prescription of drugs and to follow universal recommendations for dietary management of these patients.

Asymptomatic bacteriuria and inflammatory response urinary tract infection of elderly ambulatory women in nursing homes

Background. Bacteriuria = 10 to fifth CFU/ml is evidence of urinary tract infection in the absence of associated signs or symptoms. The presence of pyuria with asymptomatic bacteriuria established the response of elderly women against microorganisms capable of causing invasiveness or tissue injury of the urinary tract. Methods. The association between bacteriuria and pyuria was determined in 178 elderly, ambulatory women without symptoms of urinary tract infection in seven nursing homes. Urine culture results were subsequently analyzed in conjunction with absolute leukocyte count in urine. In this cross-sectional study, asymptomatic bacteriuria in elderly women was classified with and without pyuria. Results. The prevalence of asymptomatic bacteriuria was found in 44 (24.7 percent) elderly women. The presence of pyuria had a sensitivity of 63.6 percent for bacteriuria and a specificity of 91 percent. The positive predictive value for the presence of pyuria predicting those with bacteriuria was 70 percent, and the negative predictive value for the absence of pyuria predicting those without bacteriuria was 88.4 percent. Escherichia coli was the most common organism isolated in 81.8 percent of the women. Conclusions. bacteriuria = 10 to fifth CFU/ml associated with pyuria was detected in 77 percent of elderly women with asymptomatic urinary tract infections bacteriuria of < 10 to fifth CFU/ml with pyuria proves less sensitive as an indicator of urinary tract infection. Elderly women with pyuria but without bacteriuria should be studied for other causes of urinary tractinflammation