Clinical and microbiological characteristics of bacterial infections in patients with cirrhosis. A prospective cohort study from Argentina and Uruguay.

INTRODUCTION AND OBJECTIVES: there is insufficient data regarding bacterial infections in patients with cirrhosis to support recommendations for empiric antibiotic treatments, particularly in Latin America. This study aimed to evaluate bacterial infection's clinical impact and microbiological characteristics, intending to serve as a platform to revise current practices. MATERIALS AND METHODS: multicenter prospective cohort study of patients with cirrhosis and bacterial infections from Argentina and Uruguay. Patient and infection-related information were collected, focusing on microbiology, antibiotic susceptibility patterns, and outcomes. RESULTS: 472 patients were included. Spontaneous bacterial infections and urinary tract infections (UTIs) were registered in 187 (39.6%) and 116 (24.6%) patients, respectively, representing the most common infections. Of the 256 culture-positive infections, 103 (40.2%) were caused by multidrug-resistant organisms (reaching 50% for UTI), and 181 (70.7%) received adequate initial antibiotic treatment. The coverage of cefepime and ceftriaxone was over 70% for the empirical treatment of community-acquired spontaneous infections, but ceftazidime´s coverage was only 40%. For all UTI cases and for healthcare-associated or nosocomial spontaneous bacterial infections, the lower-spectrum antibiotics that covered at least 70% of the isolations were imipenem and meropenem. During hospitalization, a second bacterial infection was diagnosed in 9.8% of patients, 23.9% required at least one organ support, and 19.5% died. CONCLUSIONS: short-term mortality of bacterial infections in patients with cirrhosis is very high, and a high percentage were caused by multidrug-resistant organisms, particularly in UTIs. The information provided might serve to adapt recommendations, particularly related to empirical antibiotic treatment in Argentina and Uruguay. The study was registered in Clinical Trials (NCT03919032).

Mendelian Susceptibility to Mycobacterial Disease: Retrospective Clinical and Genetic Study in Mexico.

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare genetic disorder characterized by impaired immunity against intracellular pathogens, such as mycobacteria, attenuated Mycobacterium bovis-Bacillus Calmette-Guérin (BCG) vaccine strains, and environmental mycobacteria in otherwise healthy individuals. Retrospective study reviewed the clinical, immunological, and genetic characteristics of patients with MSMD in Mexico. Overall, 22 patients diagnosed with MSMD from 2006 to 2021 were enrolled: 14 males (64%) and eight females. After BCG vaccination, 12 patients (70%) developed BCG infection. Furthermore, 6 (22%) patients developed bacterial infections mainly caused by Salmonella, as what is described next in the text is fungal infections, particularly Histoplasma. Seven patients died of disseminated BCG disease. Thirteen different pathogenic variants were identified in IL12RB1 (n = 13), IFNGR1 (n = 3), and IFNGR2 (n = 1) genes. Interleukin-12Rß1 deficiency is the leading cause of MSMD in our cohort. Morbidity and mortality were primarily due to BCG infection.

Procalcitonina sérica como marcador de la función del injerto en el postrasplante renal inmediato

Contexto la procalcitonina (PCT) podría ser útil en la evaluación de la función del injerto renal (IR) en el postrasplante inmediato, ya que sus niveles se incrementan posterior a la elevación de citocinas inflamatorias (IL-6, TNF-ß) durante eventos de disfunción renal. Objetivo determinar la asociación de la PCT sérica con la función del injerto renal en el periodo postrasplante inmediato. Metodología cohorte retrospectiva de septiembre del 2018 a abril del 2019 en la División de Nefrología y Trasplantes, del Centro Médico Nacional de Occidente (CMNO), del Instituto Mexicano del Seguro Social (IMSS). Se incluyeron 62 receptores de trasplante renal de donante vivo (DV) y fallecido (DF) con determinación de PCT antes del séptimo día del TR y el registro de eventos de disfunción temprana del injerto (DTI), comparados con pacientes sin DTI (sDTI). Resultados los receptores con DTI presentaron niveles más altos de PCT (13,90, 3,90, 1,22 ng/mL) comparado con el grupo sin DTI (0,32, 0,31 y 0,22 ng/ml) en los días 1, 3 y 5 respectivamente; p < 0,05. Conclusiones la PCT es un marcador biológico asociado a DTI en el postrasplante renal inmediato.

Background Procalcitonin (PCT) could be useful for evaluation of the renal allograft (RG) in the immediate post-transplant since its levels increase after elevation of the inflammatory cytokines (IL-6, TNF-ß) during events of renal failure. Purpose Our objective was to determine the association of serum PCT with the function of the RG in the immediate post-transplant. Methodology A retrospective cohort from September 2018- April 2019 in the National Western Medical Center of the Mexican Social Security Institute (IMSS), was performed. Sixty-two recipients of living donor (LD) and deceased donor (DD) renal transplant (RT) with PCT evaluation before the seventh days of RT were included; and, events of early renal allograft failure (EAF) were recorded and compared to patients no EAF (nEAF). Results The recipients with EAF presented with higher PCT levels (13.90, 3.90, 1.22 ng/mL) compared to the nEAF group (0.32, 0.31, and 0.22 ng/ml) on days 1, 3, and 5, respectively (p < 0.05). Conclusions The PCT is a biological marker associated with EAF in the immediate post-transplant.

Bacterial Subversion of Autophagy in Cystic Fibrosis.

Cystic fibrosis (CF) is a genetic disease affecting more than 70,000 people worldwide. It is caused by a mutation in the cftr gene, a chloride ion transporter localized in the plasma membrane of lung epithelial cells and other organs. The loss of CFTR function alters chloride, bicarbonate, and water transport through the plasma membrane, promoting the production of a thick and sticky mucus in which bacteria including Pseudomonas aeruginosa and Burkholderia cenocepacia can produce chronic infections that eventually decrease the lung function and increase the risk of mortality. Autophagy is a well-conserved lysosomal degradation pathway that mediates pathogen clearance and plays an important role in the control of bacterial infections. In this mini-review, we describe the principal strategies used by P. aeruginosa and B. cenocepacia to survive and avoid microbicidal mechanisms within the autophagic pathway leading to the establishment of chronic inflammatory immune responses that gradually compromise the lung function and the life of CF patients.

Pseudomonas aeruginosa Isolates From a Cohort of Mexican Children With Cystic Fibrosis Show Adaptation to a Chronic Phenotype.

BACKGROUND: Long-term persistence of Pseudomonas aeruginosa in the lung of individuals with cystic fibrosis (CF) is associated with progressive selection of diverse genotypes and phenotypes. This bacterial adaptation leads to chronic infection and increased morbidity and mortality. The aim of this study was to establish the prevalence, clonal relatedness, antimicrobial susceptibility and virulence-associated phenotypes of P. aeruginosa isolates in a cohort of 50 Mexican children with CF-associated chronic lung infection. METHODS: Clonal relatedness of P. aeruginosa isolates was verified by pulsed-field gel electrophoresis. The antimicrobial susceptibility was determined by an automated system that performs bacterial identificación and antibiotic susceptibility testing (VITEK 2) and/or broth microdilution method. Biofilm formation was quantified with the crystal violet method; swarming motility was measured on soft agar, and susceptibility to normal human serum determined by reduction of colony formed units (CFUs). RESULTS: High prevalence of P. aeruginosa colonization among Mexican children with CF was confirmed; 20% (10/49) of clones identified showed a multidrug-resistant phenotype and 8.2% (4/49) an extensive drug resistance phenotype; 26.5% (13/49) of the isolates were resistant to colistin, 42.9% (21/49) presented a phenotype of adaptation associated with chronic infection and 79.6% (39/49) showed increased ability to survive in normal human serum. CONCLUSIONS: This cohort of children with CF reveals that colonizing P. aeruginosa strains predominantly display resistance to several first-line antibiotics, although most isolates were susceptible to meropenem and tobramycin; 42.9% of isolates showed a phenotype consistent with adaptation to chronic lung infection.

Mycobacterium tuberculosis promotes genomic instability in macrophages

BACKGROUND Mycobacterium tuberculosis is an intracellular pathogen, which may either block cellular defensive mechanisms and survive inside the host cell or induce cell death. Several studies are still exploring the mechanisms involved in these processes. OBJECTIVES To evaluate the genomic instability of M. tuberculosis-infected macrophages and compare it with that of uninfected macrophages. METHODS We analysed the possible variations in the genomic instability of Mycobacterium-infected macrophages using the DNA breakage detection fluorescence in situ hybridisation (DBD-FISH) technique with a whole human genome DNA probe. FINDINGS Quantitative image analyses showed a significant increase in DNA damage in infected macrophages as compared with uninfected cells. DNA breaks were localised in nuclear membrane blebs, as confirmed with DNA fragmentation assay. Furthermore, a significant increase in micronuclei and nuclear abnormalities were observed in infected macrophages versus uninfected cells. MAIN CONCLUSIONS Genomic instability occurs during mycobacterial infection and these data may be seminal for future research on host cell DNA damage in M. tuberculosis infection.

Mycobacterium tuberculosis promotes genomic instability in macrophages.

BACKGROUND: Mycobacterium tuberculosis is an intracellular pathogen, which may either block cellular defensive mechanisms and survive inside the host cell or induce cell death. Several studies are still exploring the mechanisms involved in these processes. OBJECTIVES: To evaluate the genomic instability of M. tuberculosis-infected macrophages and compare it with that of uninfected macrophages. METHODS: We analysed the possible variations in the genomic instability of Mycobacterium-infected macrophages using the DNA breakage detection fluorescence in situ hybridisation (DBD-FISH) technique with a whole human genome DNA probe. FINDINGS: Quantitative image analyses showed a significant increase in DNA damage in infected macrophages as compared with uninfected cells. DNA breaks were localised in nuclear membrane blebs, as confirmed with DNA fragmentation assay. Furthermore, a significant increase in micronuclei and nuclear abnormalities were observed in infected macrophages versus uninfected cells. MAIN CONCLUSIONS: Genomic instability occurs during mycobacterial infection and these data may be seminal for future research on host cell DNA damage in M. tuberculosis infection.

Oral Administration of Human Polyvalent IgG by Mouthwash as an Adjunctive Treatment of Chronic Oral Candidiasis.

Candida albicans is a commensal fungus that can cause disease ranging in severity from moderate to severe mucosal infections to more serious life-threating disseminated infections in severely immunocompromised hosts. Chronic mucocutaneous candidiasis (CMC) occurs in patients with mutations in genes affecting IL-17-mediated immunity, such as STAT3, AIRE, RORC, CARD9, IL12B, and IL12RB1, or gain of function (GOF) mutations in STAT1. New strategies for the treatment of candidiasis are needed because of the increased burden of infections and the emergence of drug-resistant strains. In this study, we investigated an aspect of the role of antibodies in the control of C. albicans infection. We tested in vitro the effects of C. albicans opsonization with commercial human polyvalent intravenous IgG (IV IgG) on NADPH oxidase activity and killing of the fungi by blood leukocytes from 11 healthy donors and found a significant enhancement in both phenomena that was improved by IV IgG opsonization. Then, we hypothesized that the opsonization of Candida in vivo could help its elimination by mucosal phagocytes in human patients with mucocutaneous candidiasis. We tested a novel adjunctive treatment for oral candidiasis in humans based on topical treatment with IV IgG. For this purpose, we choose two pediatric patients with well-characterized primary immunodeficiencies who are susceptible to CMC. Two 8-year-old female patients with an autosomal recessive mutation in the IL12RB1 gene (P1, with oral candidiasis) and a GOF mutation in STAT1 (P2, with severe CMC persistent since the age of 8 months and resistant to pharmacological treatments) were treated with IV IgG administered daily three times a day as a mouthwash over the course of 2 weeks. The treatment with the IV IgG mouthwash reduced C. albicans mouth infection by 98 and 70% in P1 and P2, respectively, after 13 days, and complete fungal clearance was observed after complementary nystatin and caspofungin treatments, respectively. Therefore, treatment of oral candidiasis with human polyvalent IgG administered as a mouthwash helps eliminate mucosal infection in humans, circumventing drug resistance, and opening its potential use in patients with primary or transient immunodeficiency.

Effect of oral glycine on the clinical, spirometric and inflammatory status in subjects with cystic fibrosis: a pilot randomized trial.

BACKGROUND: Patients with cystic fibrosis (CF) have airway inflammation that contributes to symptoms and to pulmonary function derangement. Current drugs used to diminish airway inflammation improve the clinical and spirometric status of patients with CF, but their use is limited due to their undesired side effects, for example, glucose intolerance, growth retardation, and cataracts with corticosteroids, gastrointestinal toxicity with ibuprofen, and macrolide resistance with azythromycin. Glycine is known to decrease activation of inflammatory cells, including alveolar macrophages and neutrophils, and is relatively inexpensive, palatable, and virtually devoid of untoward effects. These features make glycine a good candidate for antiinflammatory treatment of CF. Thus, we aimed to explore whether glycine can exert a beneficial effect in a population of patients with CF. METHODS: This was a randomized, double blinded, cross-over pilot clinical trial. Subjects with CF received, in random order, oral glycine (0.5 g/kg/day, dissolved in any liquid) and placebo (glass sugar), each during 8 weeks with an intermediate 2-week wash-out period. RESULTS: Thirteen subjects aged 6-23 years, 8 females, completed the two arms of the study. As compared with placebo, after glycine intake patients had better symptom questionnaire scores (p = 0.02), mainly regarding sputum features and dyspnea. While spirometric variables tended to decline during placebo intake, they remained stable or even increased during glycine treatment (p = 0.04 to p = 0.003). In this context, FEV1 declined 8.6% after placebo and increased 9.7% at the end of the glycine period. Pulse oximetry improved after glycine intake (p = 0.04 vs. placebo). TNF-α in serum and IL-6 and G-CSF in sputum tended to decline at the end of the glycine period (p = 0.061, p = 0.068 and p = 0.04, respectively, vs placebo). Glycine was remarkably well tolerated. CONCLUSIONS: The clinical, spirometric and inflammatory status of subjects with CF improved after just 8 weeks of glycine intake, suggesting that this amino acid might constitute a novel therapeutic tool for these patients. Thus, further studies are warranted. TRIAL REGISTRATION: www.clinicaltrials.gov , registration number: NCT01417481 , date of registration: March 12, 2012.

Two-Tailed Comet Assay (2T-Comet): Simultaneous Detection of DNA Single and Double Strand Breaks.

A modification of the original comet assay was developed for the simultaneous evaluation of DNA single strand breaks (SSBs) and double strand breaks (DSBs) in human spermatozoa. The two-dimensional perpendicular tail comet assay (2T-comet) combines non-denaturing and denaturant conditions to the same sperm nucleoid. In this case, the species-specific deproteinized sperm is first subjected to an electrophoretic field under non-denaturing conditions to mobilize isolated free discrete DNA fragments produced from DSBs; this is then followed by a second electrophoresis running perpendicular to the first one but under alkaline conditions to produce DNA denaturation, exposing SSBs on the same linear DNA chain or DNA fragments flanked by DSBs. This procedure results in a two dimensional comet tail emerging from the core where two types of original DNA affected molecule can be simultaneously discriminated. The 2T-comet is a fast, sensitive, and reliable procedure to distinguish between single and double strand DNA damage within the same cell. It is an innovative method for assessing sperm DNA integrity, which has important implications for human fertility and andrological pathology. This technique may be adapted to assess different DNA break types in other species and other cell types.

Prevalence and risk factors of acute-on-chronic liver failure in a single center from Argentina.

AIM: To study the prevalence, characteristics, risk factors and mortality at 28 d of acute-on-chronic liver failure (ACLF). METHODS: A total of 100 cirrhotic patients admitted to our hospital for more than one day were included during the period between June 2013 and December 2015. We used the European Association for the Study of the Liver-Chronic Liver Failure-Consortium diagnostic criteria for ACLF, considering it as the acute decompensation of cirrhosis associated with the presence of one or more organ failure. For the diagnosis of organic failure the Chronic Liver Failure-Sequential Organ Failure Assessment score was used. Our population was divided into patients with and without ACLF. Clinical characteristics, presence of precipitating events, potential risk factors for developing ACLF and causes of mortality were analyzed. Mortality at 28 d was evaluated. RESULTS: Twenty-nine patients (29%) developed ACLF criteria. Alcoholism, detected in 58 patients (58%), was the major etiological agent of cirrhosis. Bacterial infections were recognized as a precipitating event in 41.3% of cases and gastrointestinal bleeding in 27.5%. No precipitating event was identifiable in 27.5% of patients with ACLF. Comparing patients with and without ACLF, statistically significant risk factors were: Child Pugh score 10.2 ± 2.1 vs 8.4 ± 1.6 (P ˂ 0.0001), MELD score 20.7 ± 8.5 vs 12.3 ± 4 (P ˂ 0.0001), presence of ascites 27 (93%) vs 43 (60.5%) (P = 0.001), leukocytosis 15300 ± 8033 per cubic millimeter vs 10770 ± 5601 per cubic millimeter (P ˂ 0.0001), and high plasma levels of C reactive protein values 50.9 ± ​​46.4 mg/L vs 28.6 ± 23.4 mg/L (P ˂ 0.0019). Mortality rate was 62% (18 patients) vs 5.6% (4 patients), respectively (P < 0.0001). CONCLUSION: We observed that the ACLF is a frequent entity in this group of patients and has a significantly higher mortality rate.

Transoral CO2 Laser Microsurgery Outcomes for Early Glottic Carcinomas T1-T2

Abstract Introduction Transoral laser microsurgery (TLM) has won territory in larynx oncology, establishing itself as an effective option in treatment of glottic, supraglottic, and hypopharynx tumors. Its advantages include limited resections, a reduction in number of tracheostomies, and the use of nasogastric tubes. Moreover, its oncological benefits are similar to those from open surgery in patients with early or advanced stages, when correctly selected. Objective The objective of this study is to review oncologic outcomes obtained with the treatment of a series of glottic tumors, treated by TLM. Methods Retrospective analysis of patients previously untreated, diagnosed with squamous cell carcinoma of the glottis (T1a, T1b, T2) in a tertiary university hospital. Endpoints for analysis were local control, overall and disease-specific survival, and larynx preservation rate. Results The study group included 58 patients that met the inclusion criteria: 57 (98.3%) men and 1 (1.7%) woman. Mean age was 65.5 10.7 years (Min: 46/Max: 88). The tumor stages of the patients included were 30 T1a, 11 (19%) T1b, and 17 (29.3%) T2. Three-year overall survival rate was 89.7% (Fig. 1), and three-year disease-specific survival rate was 96.5%, three-year local control rate was 98.3%, and three-year organ preservation rate was 98.3%. Conclusion TLM is a safe and effective option in the treatment of glottis carcinomas, associated with less morbidity and a high percentage of local control, overall survival, specific survival, and organ preservation.

Transoral CO2 Laser Microsurgery Outcomes for Early Glottic Carcinomas T1-T2.

INTRODUCTION: Transoral laser microsurgery (TLM) has won territory in larynx oncology, establishing itself as an effective option in treatment of glottic, supraglottic, and hypopharynx tumors. Its advantages include limited resections, a reduction in number of tracheostomies, and the use of nasogastric tubes. Moreover, its oncological benefits are similar to those from open surgery in patients with early or advanced stages, when correctly selected. OBJECTIVE: The objective of this study is to review oncologic outcomes obtained with the treatment of a series of glottic tumors, treated by TLM. METHODS: Retrospective analysis of patients previously untreated, diagnosed with squamous cell carcinoma of the glottis (T1a, T1b, T2) in a tertiary university hospital. Endpoints for analysis were local control, overall and disease-specific survival, and larynx preservation rate. RESULTS: The study group included 58 patients that met the inclusion criteria: 57 (98.3%) men and 1 (1.7%) woman. Mean age was 65.5 ± 10.7 years (Min: 46/Max: 88). The tumor stages of the patients included were 30 T1a, 11 (19%) T1b, and 17 (29.3%) T2. Three-year overall survival rate was 89.7% (Fig. 1), and three-year disease-specific survival rate was 96.5%, three-year local control rate was 98.3%, and three-year organ preservation rate was 98.3%. CONCLUSION: TLM is a safe and effective option in the treatment of glottis carcinomas, associated with less morbidity and a high percentage of local control, overall survival, specific survival, and organ preservation.

Complications in CO2 Laser Transoral Microsurgery for Larynx Carcinomas

Abstract Introduction Transoral laser microsurgery (TLM) has established itself as an effective option in the management of malignant tumors of the glottis, supraglottis, and hypopharynx. Nonetheless, TLM is not a harmless technique. Complications such as bleeding, dyspnea, or ignition of the air may appear in this type of surgery. Objective The aim of this study is to describe the complications that occurred in a group of patients treated for glottic and supraglottic carcinomas in all stages by TLM. Methods This study is a retrospective analysis of patients diagnosed with squamous cell carcinoma of the glottis and supraglottis for all stages (T1, T2, T3, T4), N -/ + , M -/+ treated with TLM between January 2009 and March 2012 in a tertiary hospital. Results Ninety-eight patients met the inclusion criteria, which had undergone a total of 131 interventions. Ninety-four (95.9%) patients were male and 4 (4.1%) were female. The mean age was 64.2 years ( 10.7 years =min 45; max 88). The presence of intraoperative complications was low, affecting only 2% of patients. Immediate postoperative complications occurred in 6.1%, whereas delayed complications affected 13.2% of patients, without any of them being fatal. Conclusion TLM has shown good oncologic results and low complication rate compared with traditional open surgery during intervention, in the immediate and delayed postoperative period and in the long-term with respect to radiotherapy.

Complications in CO2 Laser Transoral Microsurgery for Larynx Carcinomas.

Introduction Transoral laser microsurgery (TLM) has established itself as an effective option in the management of malignant tumors of the glottis, supraglottis, and hypopharynx. Nonetheless, TLM is not a harmless technique. Complications such as bleeding, dyspnea, or ignition of the air may appear in this type of surgery. Objective The aim of this study is to describe the complications that occurred in a group of patients treated for glottic and supraglottic carcinomas in all stages by TLM. Methods This study is a retrospective analysis of patients diagnosed with squamous cell carcinoma of the glottis and supraglottis for all stages (T1, T2, T3, T4), N -/ + , M -/+ treated with TLM between January 2009 and March 2012 in a tertiary hospital. Results Ninety-eight patients met the inclusion criteria, which had undergone a total of 131 interventions. Ninety-four (95.9%) patients were male and 4 (4.1%) were female. The mean age was 64.2 years (± 10.7 years = min 45; max 88). The presence of intraoperative complications was low, affecting only 2% of patients. Immediate postoperative complications occurred in 6.1%, whereas delayed complications affected 13.2% of patients, without any of them being fatal. Conclusion TLM has shown good oncologic results and low complication rate compared with traditional open surgery during intervention, in the immediate and delayed postoperative period and in the long-term with respect to radiotherapy.

Implementation of a program to improve the quality of colonoscopy increases the neoplasia detection rate: a prospective study.

BACKGROUND AND STUDY AIMS: Endoscopists worldwide have been encouraged to report quality indicators in order to evaluate their performance. We aimed to determine whether a program to improve the quality of colonoscopy results in better rates of neoplasia detection. PATIENTS AND METHODS: This is a prospective study set in a private endoscopy center. From May 2009 to March 2010, we evaluated 1573 consecutive colonoscopies (group 1). After the implementation of a quality program, from February 2011 to January 2012, we prospectively evaluated 1583 colonoscopies (group 2). Our quality-enhancing intervention consisted of instructing both patients and endoscopists. We measured the cecal intubation rate and the neoplasia detection rate. Overall neoplasias, high-risk adenomas, carcinomas, right colon adenomas, and adenomas detected in screening studies were analyzed. RESULTS: Cecal intubation was documented in 1384 cases from group 1 (88 %) and 1534 from group 2 (96.9 %) (P < 0.0001). The neoplasia detection rates in groups 1 and 2 were, respectively: neoplasias 288 (18.3 %) and 427 (27 %) (P < 0.0001), high-risk adenomas 76 (4.8 %) and 142 (9 %) (P < 0.0001), carcinomas 16 (1 %) and 21 (1.3 %) (P = 0.52), right colon adenomas 112 (7.1 %) and 154 (9.7 %) (P = 0.01), and adenomas 141 (16.5 %) and 233 (28 %) (P < 0.0001). CONCLUSIONS: Implementation of a quality program improves the neoplasia detection rate. Because of the small number of cancerous lesions found in both groups, we were unable to identify differences in the carcinoma detection rate.

Evaluation of environmental genotoxicity by comet assay in Columba livia.

The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as "sentinels," as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection-fluorescence in situ hybridization (DBD-FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD-FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants.

DNA damage in spermatozoa from infertile men with varicocele evaluated by sperm chromatin dispersion and DBD-FISH.

PURPOSE: Evaluation of DNA integrity is an important test, possessing greater diagnostic and prognostic significance for couples requiring assisted reproduction. In this study, we evaluate the levels of DNA damage in infertile patients with varicocele with respect to fertile males by the sperm chromatin dispersion (SCD) test. The presence of DNA breaks in spermatozoa was confirmed by DNA breakage detection-fluorescence in situ hybridization (DBD-FISH). METHODS: In this study, the frequency of sperm cells with fragmented DNA was studied in a group of 20 infertile patients with varicocele and compared with 20 fertile males. The spermatozoa were processed to classify different levels of DNA fragmentation using the Halosperm(®) kit, an improved SCD test, and DBD-FISH. RESULTS: Patients with varicocele showed 25.54 ± 28.17 % of spermatozoa with fragmented DNA, significantly higher than those of the group of fertile subjects (11.54 ± 3.88 %). The proportion of degraded cells in total sperm cells with fragmented DNA was sixfold higher in the case of patients with varicocele. The presence of DNA breaks in spermatozoa was confirmed by DBD-FISH. 5-bp Classical satellite-2 regions showed greater sensitivity to damage or "breakage" than alphoid satellite regions. CONCLUSIONS: Our finding preliminary demonstrated an increase of DNA fragmentation associated to severe sperm damage, in infertile patients with varicocele with respect to fertile males. 5-bp Classical satellite-2 regions showed greater sensitivity to damage or "breakage" than alphoid satellite regions.

Narrow-host-range bacteriophages that infect Rhizobium etli associate with distinct genomic types.

In this work, we isolated and characterized 14 bacteriophages that infect Rhizobium etli. They were obtained from rhizosphere soil of bean plants from agricultural lands in Mexico using an enrichment method. The host range of these phages was narrow but variable within a collection of 48 R. etli strains. We obtained the complete genome sequence of nine phages. Four phages were resistant to several restriction enzymes and in vivo cloning, probably due to nucleotide modifications. The genome size of the sequenced phages varied from 43 kb to 115 kb, with a median size of ≈ 45 to 50 kb. A large proportion of open reading frames of these phage genomes (65 to 70%) consisted of hypothetical and orphan genes. The remainder encoded proteins needed for phage morphogenesis and DNA synthesis and processing, among other functions, and a minor percentage represented genes of bacterial origin. We classified these phages into four genomic types on the basis of their genomic similarity, gene content, and host range. Since there are no reports of similar sequences, we propose that these bacteriophages correspond to novel species.

Diagnóstico por imagen de un quiste hidatídico pulmonar gigante. Reporte de un caso clínico / Diagnostic imaging of a giant pulmonary hydatid cyst. Clinical Case Report

La Hidatidosis o equinococcosis es una enfermedad clasificada dentro de las ciclozoonosis. Es producida por las formas larvarias de Echinococcus granulosus que parasita el intestino del perro. Los quistes hidatídicos poseen como segunda localización el pulmón en un 10%. Se presenta el caso clínico de una paciente de 82 años de edad que presento un cuadro clínico de 1 mes de evolución caracterizado por accesos de tos productiva verdosa, escalofríos, alzas térmicas , al examen físico se auscultó murmullo vesicular disminuido en campo pulmonar izquierdo. Se realizó radiografía de tórax inconclusas donde se evidencio dos imágenes radiopacas circulares, homogéneas , en cuadrante superior e inferior de campo pulmonar izquierdo. La tomografía multicorte informo quistes pulmonares gigantes en he-mitorax izquierdo, se realizo toracotomía exploratoria y quistectomia, finalmente la patología confirmo quistes hidatídicos pulmonares gigantes y proceso inflamatorio crónico activo.

Hydatidosis or echinococcosis is a disease classified within ciclozoonosis. It is produced by the larval forms of Echinococcusgranulosus that parasitizes the intestine of the dog. Hydatid cysts cover the lung with 10%, beeingthe second location. This is a case report of a patient of 82 years old who had a 1 month clinical evolution characterized by greenish productive coughing, chills, heat rises , physical examination decreased breath sounds auscultated in left lung field, The X ray (unfinished) evidenced two circular homogeneousradio-pacities upper quadrant and lower left lung field, multislice CT reported giant lung cysts, exploratory thoracotomy and cystectomy was performed, finally pathology confirmed pulmonary giant hydatid cysts and active chronic inflammatory process.