Clostridioides difficile-associated diarrhea in surgical service patients in Mexico. / Diarrea asociada a Clostridioides difficile en pacientes de servicios quirúrgicos en México.

INTRODUCTION: Clostridioides difficile is the first cause of healthcare-associated diarrhea in developed countries. In recent years the incidence of C. difficile infection (CDI) has increased worldwide. There is not much information on the topic in Mexico, and little is known about the risk factors for the infection in patients that are hospitalized in surgical services. MATERIALS AND METHODS: A case-control study was conducted that compared the epidemiologic findings and risk factors between surgical patients with PCR-confirmed CDI, surgical patients with diarrhea and a negative PCR test, and surgical patients with no diarrhea. The statistical analysis was carried out using the SPSS version 22.0 program. RESULTS: The majority of the surgical patients with CDI belonged to the areas of neurosurgery, cardiac surgery, orthopedics, and general surgery. A total of 53% of the CDI cases were associated with the hypervirulent CD NAP1/027 strain. The presence of mucus in stools (OR: 1.5, P=.001), fever (OR: 1.4, P=.011), leukocytes in stools (OR: 3.2, P<.001), hospitalization within the past 12weeks (OR: 2.0, P<.001), antibiotic use (OR: 1.3, P=.023), and ceftriaxone use (OR: 1.4, P=.01) were independent risk factors for the development of CDI. CONCLUSIONS: C. difficile-induced diarrhea in the surgical services is frequent at the Hospital Civil de Guadalajara "Fray Antonio Alcalde".

Biochemical characterization of the venom from the Mexican scorpion Centruroides ornatus, a dangerous species to humans.

Every year in Mexico, around 300,000 people suffer from accidents related to scorpion stings. Among the scorpion species dangerous to human is Centruroides ornatus, whose venom characterization is described here. From this venom, a total of 114 components were found using chromatographic separation and mass spectrometry analysis. The most abundant ones have molecular masses between 3000-4000 Da and 6000-8000 Da respectively, similar to other known K+ and Na+-channel specific scorpion peptides. Using intraperitoneal injections into CD1 mice, we were able to identify and fully sequenced three new lethal toxins. We propose to name them Co1, Co2 and Co3 toxins, which correspond to toxins 1 to 3 of the abbreviated species name (Co). Electrophysiology analysis of these peptides using heterologously expressed human Na+-channels revealed a typical ß-toxin effect. Peptide Co52 (the most abundant peptide in the venom) showed no activity in our in vivo and in vitro model assays. A phylogenetic analysis groups the Co1, Co2 and Co3 among other ß-toxins from Centruroides scorpions. Peptide Co52 segregates among peptides of unknown defined functions.

Utilidad de la gammagrafía con hematíes desnaturalizados por calor marcados con 99mTc en el diagnóstico de una esplenosis intramuscular / Usefulness of 99mTc labelled heat-denatured red blood cell scintigraphy in the diagnosis of intramuscular splenosi

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Impact of food model (micro)structure on the microbial inactivation efficacy of cold atmospheric plasma.

The large potential of cold atmospheric plasma (CAP) for food decontamination has recently been recognized. Room-temperature gas plasmas can decontaminate foods without causing undesired changes. This innovative technology is a promising alternative for treating fresh produce. However, more fundamental studies are needed before its application in the food industry. The impact of the food structure on CAP decontamination efficacy of Salmonella Typhimurium and Listeria monocytogenes was studied. Cells were grown planktonically or as surface colonies in/on model systems. Both microorganisms were grown in lab culture media in petri dishes at 20°C until cells reached the stationary phase. Before CAP treatment, cells were deposited in a liquid carrier, on a solid(like) surface or on a filter. A dielectric barrier discharge reactor generated helium-oxygen plasma, which was used to treat samples up to 10min. Although L. monocytogenes is more resistant to CAP treatment, similar trends in inactivation behavior as for S. Typhimurium are observed, with log reductions in the range [1.0-2.9] for S. Typhimurium and [0.2-2.2] for L. monocytogenes. For both microorganisms, cells grown planktonically are easily inactivated, as compared to surface colonies. More stressing growth conditions, due to cell immobilization, result in more resistant cells during CAP treatment. The main difference between the inactivation support systems is the absence or presence of a shoulder phase. For experiments in the liquid carrier, which exhibit a long shoulder, the plasma components need to diffuse and penetrate through the medium. This explains the higher efficacies of CAP treatment on cells deposited on a solid(like) surface or on a filter. This research demonstrates that the food structure influences the cell inactivation behavior and efficacy of CAP, and indicates that food intrinsic factors need to be accounted when designing plasma treatment.

Hipoestesia mentoniana como manifestación de metástasis mandibular diagnosticada en la gammagrafía ósea / Numb chin syndrome as a manifestation of jaw metastasis diagnosed in a bone scan

El síndrome del mentón entumecido (numb chin syndrome [NCS]) en muchos casos puede representar una patología banal, pero al poder asociarse con procesos malignos, su presencia debe alertar al clínico como posible manifestación de una enfermedad maligna oculta. En pacientes previamente diagnosticados de una neoplasia, representa a menudo un signo ominoso que indica mal pronóstico por el rápido progreso de la enfermedad. Se presenta el caso de un paciente de 62 años diagnosticado de cáncer de pulmón y de vejiga que aqueja sensación de «acorchamiento» en zona mentoniana. La gammagrafía ósea confirma la sospecha de enfermedad metastásica ósea falleciendo a los 2 meses de manifestarse este signo (AU)

In many cases, numb chin syndrome (NCS) may represent a banal pathology. However, as it can be associated with malignant processes, its presence should alert the clinician of a possible occult disease. In patients already diagnosed with cancer, it often represents an ominous sign that indicates poor prognosis, due to the rapid progress of the disease. The case is presented of a 62-year-old man diagnosed with synchronous lung and bladder cancer, who suddenly complained of numbness in the chin. The bone scan confirmed the suspicion of metastastic bone disease, and the patient died two months after the appearance of this sign (AU)

Optimal experimental design for discriminating between microbial growth models as function of suboptimal temperature: From in silico to in vivo.

Temperature is an important food preservation factor, affecting microbial growth. Secondary predictive models can be used for describing the impact of this factor on microbial growth. In other words, the microbial behavior can be described in a dynamic environment with the use of a primary and secondary model. Two models for describing the effect of temperature on the microbial growth rate are the cardinal temperature model with inflection (CTMI) (Rosso et al., 1993) and its adapted version (aCTMI) (Le Marc et al., 2002). Although Escherichia coli is commonly modeled using CTMI, there are indications that aCTMI may be more appropriate (Van Derlinden and Van Impe, 2012a). For clarifying this, the method of Optimal experiment design for model discrimination (OED/MD) will be used in this work (Donckels et al., 2009; Schwaab et al., 2008). Results from an in silico study point out the required direction. Whereas the results of the in vivo study give a more realistic answer to the research question. Finally, discrimination unravelled the appropriate model for the needed use.

Numb chin syndrome as a manifestation of jaw metastasis diagnosed in a bone scan.

In many cases, numb chin syndrome (NCS) may represent a banal pathology. However, as it can be associated with malignant processes, its presence should alert the clinician of a possible occult disease. In patients already diagnosed with cancer, it often represents an ominous sign that indicates poor prognosis, due to the rapid progress of the disease. The case is presented of a 62-year-old man diagnosed with synchronous lung and bladder cancer, who suddenly complained of numbness in the chin. The bone scan confirmed the suspicion of metastastic bone disease, and the patient died two months after the appearance of this sign.

Species distribution and antifungal susceptibility of bloodstream fungal isolates in paediatric patients in Mexico: a nationwide surveillance study.

OBJECTIVES: To establish the species distribution and in vitro susceptibilities of 358 bloodstream fungal isolates from paediatric patients in Mexico. METHODS: Isolates were collected during a 2 year surveillance programme in 14 medical centres in 10 Mexican states. A molecular approach was used to determine the Candida parapsilosis species complex. In vitro susceptibility to amphotericin B, fluconazole, voriconazole, itraconazole, posaconazole, caspofungin, anidulafungin and micafungin was determined according to CLSI procedures. Species-specific clinical breakpoints for fluconazole, voriconazole and echinocandins were applied. RESULTS: Candida spp. accounted for 98.33% of fungaemias, including 127 Candida albicans isolates, 127 C. parapsilosis complex isolates (121 C. parapsilosis sensu stricto, 4 Candida orthopsilosis and 2 Candida metapsilosis strains) and 72 Candida tropicalis isolates. C. albicans and C. parapsilosis complex were the species predominant in neonates (48 cases each; 41.02%). C. parapsilosis complex was also the predominant species in patients 1 month to <2 years of age (P = 0.007). In contrast, C. albicans was the most frequent species in patients aged 2 to <12 years (P = 0.003). Antifungal resistance was rare among the subset of isolates. Candida glabrata showed the highest resistance rate to amphotericin B (1/9 isolates), fluconazole (1/9 isolates) and itraconazole (2/9 isolates). CONCLUSIONS: The species distribution differed with the age of the patients, with C. albicans and C. parapsilosis complex being the most commonly isolated species. C. glabrata showed the highest resistance rate to amphotericin B, fluconazole and itraconazole. This is the first study of fungaemia episodes in Mexican children.

Acinetobacter baumannii infections in a tertiary care hospital in Mexico over the past 13 years.

BACKGROUND: Acinetobacter baumannii has evolved from an opportunistic pathogen into a common and persistent nosocomial bacterium capable of causing severe infections during endemic and epidemic periods. METHODS: The study period extended from January 1999 to December 2011 and involved patients hospitalized at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, Jalisco, Mexico. From each patient, a single isolate was obtained, and a total of 3,680 unique isolates were collected. Susceptibility tests were performed according to the guidelines of the Clinical and Laboratory Standards Institute. RESULTS: A. baumannii has disseminated throughout the Hospital Civil de Guadalajara, Fray Antonio Alcalde, since 1999. A. baumannii isolates obtained from patients treated in the adult intensive care unit represent the majority of the isolates that have been collected. In addition, A. baumannii was isolated from the adult neurosurgical ward and the adult internal medicine ward, and these isolates were frequently obtained from secretions. A persistent decrease in the susceptibility of A. baumannii isolates to meropenem (92% in 1999 to 12% in 2011), imipenem and amikacin has been observed. CONCLUSIONS: A. baumannii became an endemic nosocomial pathogen during the study period at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, and has exhibited a persistent decrease in susceptibility to all categories of antimicrobial agents over the past 13 years.

Inactivation of Salmonella enterica serovar Typhimurium on fresh produce by cold atmospheric gas plasma technology.

Cold atmospheric gas plasma treatment (CAP) is an alternative approach for the decontamination of fresh and minimally processed food. In this study, the effects of growth phase, growth temperature and chemical treatment regime on the inactivation of Salmonella enterica serovar Typhimurium (S. Typhimurium) by Nitrogen CAP were examined. Furthermore, the efficacy of CAP treatment for decontaminating lettuce and strawberry surfaces and potato tissue inoculated with S. Typhimurium was evaluated. It was found that the rate of inactivation of S. Typhimurium was independent of the growth phase, growth temperature and chemical treatment regime. Under optimal conditions, a 2 min treatment resulted in a 2.71 log-reduction of S. Typhimurium viability on membrane filters whereas a 15 min treatment was necessary to achieve 2.72, 1.76 and 0.94 log-reductions of viability on lettuce, strawberry and potato, respectively. We suggest that the differing efficiency of CAP treatment on the inactivation of S. Typhimurium on these different types of fresh foods is a consequence of their surface features. Scanning electron microscopy of the surface structures of contaminated samples of lettuce, strawberry and potato revealed topographical features whereby S. Typhimurium cells could be protected from the active species generated by plasma.

Integración de los factores de riesgo coronario no convencionales en los diagnósticos de enfermería / Integration of unconventional coronary risk factors during nursing diagnoses", "_i": "

La evidencia sugiere que los factores de riesgo cardiovascular no convencionales podrían ser considerados para la construcción de diagnósticos de enfermería con la finalidad de prevenir un infarto súbito en el subgrupo de individuos que presentan factores tradicionales en límites normales. Objetivos: a) señalar la importancia de conformar algunos elementos clínico-observacionales y de laboratorio en la valoración de enfermería para integrar los factores de riesgo tradicionales y no convencionales para enfermedad arterial coronaria en los diagnósticos de enfermería; b) explicar y entender las bases moleculares causales de dichos factores de riesgo no convencionales en la génesis del proceso de formación de la placa aterosclerótica. La redacción del diagnóstico propuesto para los casos presentados se realizó con base al formato PES (Problema, etiología, signos y síntomas), auxiliado por el Modelo del Déficit de Autocuidado de Orem y la propuesta de Alfaro sugiriendo la nomenclatura de la NANDA. Discusión: La redacción de diagnósticos de riesgo cardiovascular requiere más allá de una valoración clínico-observacional; la enfermería necesita conocer los avances en el escrutinio de los factores de riesgo coronario desde la intimidad de la biología molecular y valerse de los recursos de laboratorio para fundamentar el diagnóstico y sus intervenciones.

Evidence suggests non conventional cardiovascular risk factors could be considered in nursing diagnostics construction aiming to prevent a sudden infarction within a group of individuals that show traditional factors at normal limits. Objectives: a) point out the importance of assembling some clinical observational and laboratory elements in the nursing evaluation in order to integrate traditional and non conventional risk factors for a coronary arterial disease; b) explain and understand the molecular bases causing such non conventional risk factors in the process of the arteriosclerosis plaque formation. The proposed diagnostics wording for the submitted cases was done based on the PES format assisted by the Orem’s Self-Care Deficit Model and the Alfaro’s proposal suggesting a NANDA nomenclature. Discussion: Cardiovascular risk diagnostics wording requires more than a clinical- observational evaluation; nursing needs to know the advances on the coronary risk factors scrutiny from the intimacy of molecular biology and make use of laboratory resources to lay foundation for diagnostics and its interventions.

Estilo de vida: Precursor de factores de riesgo cardiovascular en adultos sanos / Lifestyle: Cardiovascular risk factor precursor in healthy adult people", "_i": "

Introducción: El estilo de vida es un aspecto de la actividad vital de la persona y contribuye a desarrollar factores de riesgo para diferentes enfermedades. En la población adulta mexicana, la alta prevalencia de sobrepeso y obesidad coloca a este grupo etario en situaciones de riesgo relacionadas a enfermedades cardiovasculares. Objetivo: Determinar los factores de riesgo cardiovascular (FRCV) y su asociación con el estilo de vida promotor de salud (EVPS) en adultos sanos. Material y métodos: Estudio descriptivo, transversal; con una muestra de 160 hombres y mujeres de 20 a 59 años. Se realizó medición de presión arterial y antropométrica para determinar el índice de masa corporal, se tomaron muestras sanguíneas para determinación de glucosa y colesterol. El estilo de vida promotor de salud se midió con el cuestionario perfil de estilo de vida promotor de salud II (PEPS-II). Los datos fueron analizados con estadística descriptiva y modelos de regresión lineal múltiple. Resultados: Los FRCV identificados fueron obesidad 64.4%, hiperglucemia 35%, hipercolesterolemia 7.5% y presión arterial normal alta 4.4%. El perfil de estilo de vida promotor de salud fue bajo (media = 49.6 ± 13.86). Los factores personales biológicos mostraron efecto sobre el EVPS (F (3,156) = 3.856, p = .011), explicando el 5.1% de la varianza (R2 ajustada = .051). Conclusiones: Los factores de riesgo en la población estudiada fueron obesidad e hiperglucemia que pueden explicarse por la baja percepción que se tiene de la relación del estilo de vida con el riesgo para la salud.

Introduction: Lifestyle is an aspect of a person’s vital activity and contributes to the development of risk factors for different illnesses. In the adult Mexican population, the high prevalence of over-weight and obesity places this group in situations of risk related to cardiovascular illnesses. Objective: To determine cardiovascular risk factors (CVRF) and their association with Health promoting lifestyle (HPLS) in healthy adults. Material and methods: Cross-sectional descriptive study; with a sample made up of 160 men and women between 20 and 59 years of age. Blood pressure and anthropometrical readings were carried out to determine the body mass index, blood samples were taken in order to ascertain glucose and cholesterol levels. Health promoting lifestyles which promote health were measured using the Profile for Lifestyles which Promote Health II (PLPH-II). The information was analyzed utilizing descriptive statistics and multiple lineal regression models. Results: The CVRF identified were obesity 64.4%, hyperglycemia 35%, hypercholesterolemia 7.5% and normal high blood pressure 4.4%. The profile for lifestyles which promote health was low (average = 49.6 ± 13.86). Personal biological factors were shown to affect the HPLS (F (3,156) = 3.856, p = .011), explaining the 5.1% variance (R2 adjusted = .051).Conclusions: Risk factors in the population studied were obesity and hyperglycemia which may be explained by the low perception which these have in relation to a lifestyle that risks health.

Development of a structure-based model for the competitive growth of Listeria innocua in minced chicken breasts.

Most predictive models are based on planktonic microbial growth in broth and, therefore, do not deal with diffusional limitations generated by the solid-food structure. Recently, a few approaches have incorporated the diffusional component, but still on the basis of pure cultures growing in homogenous supports. In this work, a transport-phenomenon model that considers the complex and dynamic structure of real foods, as well as its background microflora, has been developed. This structure-based model was applied to the competitive growth of Listeria innocua in minced chicken breasts, considering oxygen as the limiting substrate. Physical structure and microbial growth in minced meat were compared to those reported for meat-based kappa-carrageenan gels by means of scanning electron microscopy (SEM) and viable counts. In both systems, microbial growth was affected by diffusional limitations, as compared with broth cultures. However, significant differences in their physical structure and a key effect of the indigenous microflora and the meat tissue itself, resulted in different extent and distribution of microbial growth. The approach here developed, useful for food safety purposes, has been shown to provide a reasonably good simulation of experimental data in minced breasts.

Decisive role of structure in food microbial colonization and implications for predictive microbiology.

Predictive models must consider the significant effect of the physical structure of the food on the magnitude and type of microbial growth. Before such models are developed, a thorough characterization of the food structure is mandatory because this information will determine the modeling approach. In this work, several physical structures common in poultry products were classified and described. Chicken breast skin and flesh and minced breasts were examined by scanning electron microscopy and compared with a meat-based model food. Such systems were surface or internally inoculated with Listeria innocua and incubated at 25 degrees C for 24 h. Different structures, including several substructures, found in the studied systems affected microbial distribution and growth. Based on these experimental findings, the most suitable type of model for each physical structure was determined. This information provides further clarification for predictive microbiology models.

Staphylococcal cassette chromosome mec (SCC mec) in methicillin-resistant coagulase-negative staphylococci. A review and the experience in a tertiary-care setting.

Coagulase-negative staphylococci (CNS) are increasingly recognized to cause clinically significant infections, with S. epidermidis often cited as the third most common cause of nosocomial sepsis. Among CNS, there is a high prevalence of methicillin resistance associated with staphylococcal cassette chromosome (SCCmec) elements. Although identical SCCmec types can exist in S. aureus and CNS, some novel classes of SCCmec may be unique to CNS. Differences in the accuracy of identification of CNS species and use of non-standardized methods for the detection of methicillin resistance have led to confusing data in the literature. In addition to the review of SCCmec in CNS, in this paper we report a 2-year surveillance of methicillin-resistant CNS in a tertiary-care hospital in Guadalajara, Mexico.

Metallo-beta-lactamase gene bla(IMP-15) in a class 1 integron, In95, from Pseudomonas aeruginosa clinical isolates from a hospital in Mexico.

During 2003, 40 carbapenem-resistant Pseudomonas aeruginosa clinical isolates collected in a Mexican tertiary-care hospital were screened for metallo-beta-lactamase production. Thirteen isolates produced IMP-15, and 12 had a single pulsed-field gel electrophoresis pattern. The bla(IMP-15) gene cassette was inserted in a plasmid-borne integron with a unique array of gene cassettes and was named In95.

Results from the ARTEMIS DISK Global Antifungal Surveillance study, 1997 to 2005: an 8.5-year analysis of susceptibilities of Candida species and other yeast species to fluconazole and voriconazole determined by CLSI standardized disk diffusion testing.

Fluconazole in vitro susceptibility test results for 205,329 yeasts were collected from 134 study sites in 40 countries from June 1997 through December 2005. Data were collected for 147,776 yeast isolates tested with voriconazole from 2001 through 2005. All investigators tested clinical yeast isolates by the CLSI M44-A disk diffusion method. Test plates were automatically read and results recorded with a BIOMIC image analysis system. Species, drug, zone diameter, susceptibility category, and quality control results were collected quarterly. Duplicate (same patient, same species, and same susceptible-resistant biotype profile during any 7-day period) and uncontrolled test results were not analyzed. Overall, 90.1% of all Candida isolates tested were susceptible (S) to fluconazole; however, 10 of the 22 species identified exhibited decreased susceptibility (<75% S) on the order of that seen with the resistant (R) species C. glabrata and C. krusei. Among 137,487 isolates of Candida spp. tested against voriconazole, 94.8% were S and 3.1% were R. Less than 30% of fluconazole-resistant isolates of C. albicans, C. glabrata, C. tropicalis, and C. rugosa remained S to voriconazole. The non-Candida yeasts (8,821 isolates) were generally less susceptible to fluconazole than Candida spp. but, aside from Rhodotorula spp., remained susceptible to voriconazole. This survey demonstrates the broad spectrum of these azoles against the most common opportunistic yeast pathogens but identifies several less common yeast species with decreased susceptibility to antifungal agents. These organisms may pose a future threat to optimal antifungal therapy and emphasize the importance of prompt and accurate species identification.

Molecular characterisation of a dominant methicillin-resistant Staphylococcus aureus (MRSA) clone in a Mexican hospital (1999-2003).

Methicillin-resistant Staphylococcus aureus (MRSA) isolates (n = 216), collected between January 1999 and May 2003 in a tertiary-care university hospital in Guadalajara, Mexico, were characterised by antibiotype, pulsed-field gel electrophoresis (PFGE) of SmaI macrorestriction fragments, and hybridisation of ClaI digests with mecA- and Tn554-specific DNA probes. Representatives of the single clonal type found were analysed by spa typing, multilocus sequence typing and staphylococcal chromosomal cassette mec (SCCmec) typing, and were tested for the presence of 22 virulence determinants and agr type. A single PFGE pattern was identified, with minor variations over time, with spa type 2, sequence type 5, SCCmec type II, agr type 2 and the presence of the enterotoxin genes seg and sei, the gamma-haemolysin variant gene hlg-v and the leukocidin lukE-lukD genes. In addition, the isolates showed antimicrobial resistance to beta-lactams, macrolides, chloramphenicol and imipenem, and susceptibility to gentamicin, rifampicin, trimethoprim-sulphamethoxazole and vancomycin. Following its appearance in 1997, this clone spread within the hospital, and is now present in most of the hospital units and wards.