Regulation of CO2 by the sea in areas around Latin America in a context of climate change.

Anthropogenic activities are increasing the atmospheric carbon dioxide (CO2); around a third of the CO2 emitted by these activities has been taken up by the ocean. Nevertheless, this marine ecosystem service of regulation remains largely invisible to society, and not enough is known about regional differences and trends in sea-air CO2 fluxes (FCO2), especially in the Southern Hemisphere. The objectives of this work were as follows: first to put values of FCO2 integrated over the exclusive economic zones (EEZ) of five Latin-American countries (Argentina, Brazil, Mexico, Peru, and Venezuela) into perspective regarding total country-level greenhouse gases (GHG) emissions. Second, to assess the variability of two main biological factors affecting FCO2 at marine ecological time series (METS) in these areas. FCO2 over the EEZs were estimated using the NEMO model, and GHG emissions were taken from reports to the UN Framework Convention on Climate Change. For each METS, the variability in phytoplankton biomass (indexed by chlorophyll-a concentration, Chla) and abundance of different cell sizes (phy-size) were analyzed at two time periods (2000-2015 and 2007-2015). Estimates of FCO2 at the analyzed EEZs showed high variability among each other and non-negligible values in the context of greenhouse gas emissions. The trends observed at the METS indicated, in some cases, an increase in Chla (e.g., EPEA-Argentina) and a decrease in others (e.g., IMARPE-Peru). Evidence of increasing populations of small size-phytoplankton was observed (e.g., EPEA-Argentina, Ensenada-Mexico), which would affect the carbon export to the deep ocean. These results highlight the relevance of ocean health and its ecosystem service of regulation when discussing carbon net emissions and budgets.

Seroprevalence of HCV, HBV and HIV in two inner-city London emergency departments.

SUMMARY: In this paper we build on work investigating the feasibility of human immunodeficiency virus (HIV) testing in emergency departments (EDs), estimating the prevalence of hepatitis B, C and HIV infections among persons attending two inner-London EDs, identifying factors associated with testing positive in an ED. We also undertook molecular characterisation to look at the diversity of the viruses circulating in these individuals, and the presence of clinically significant mutations which impact on treatment and control.Blood-borne virus (BBV) testing in non-traditional settings is feasible, with emergency departments (ED) potentially effective at reaching vulnerable and underserved populations. We investigated the feasibility of BBV testing within two inner-London EDs. Residual samples from biochemistry for adults (⩾18 years) attending The Royal Free London Hospital (RFLH) or the University College London Hospital (UCLH) ED between January and June 2015 were tested for human immunodeficiency virus (HIV)Ag/Ab, anti-hepatitis C (HCV) and HBsAg. PCR and sequence analysis were conducted on reactive samples. Sero-prevalence among persons attending RFH and UCLH with residual samples (1287 and 1546), respectively, were 1.1% and 1.0% for HBsAg, 1.6% and 2.3% for anti-HCV, 0.9% and 1.6% for HCV RNA, and 1.3% and 2.2% for HIV. For RFH, HBsAg positivity was more likely among persons of black vs. white ethnicity (odds ratio 9.08; 95% confidence interval 2.72-30), with anti-HCV positivity less likely among females (0.15, 95% CI 0.04-0.50). For UCLH, HBsAg positivity was more likely among non-white ethnicity (13.34, 95% CI 2.20-80.86 (Asian); 8.03, 95% CI 1.12-57.61 (black); and 8.11, 95% CI 1.13-58.18 (other/mixed)). Anti-HCV positivity was more likely among 36-55 year olds vs. ⩾56 years (7.69, 95% CI 2.24-26.41), and less likely among females (0.24, 95% CI 0.09-0.65). Persons positive for HIV-markers were more likely to be of black vs. white ethnicity (4.51, 95% CI 1.63-12.45), and less likely to have one ED attendance (0.39, 95% CI 0.17-0.88), or female (0.12, 95% CI 0.04-0.42). These results indicate that BBV-testing in EDs is feasible, providing a basis for further studies to explore provider and patient acceptability, referral into care and cost-effectiveness.

Clinical and endoscopic features in patients with hospital-acquired diarrhea associated with Clostridium difficile infection. / Características clínicas y endoscópicas en diarrea hospitalaria asociada a infección por Clostridium difficile.

INTRODUCTION AND AIMS: Clostridium difficile infection is the main cause of hospital-acquired diarrhea, and the clinical and endoscopic findings in those patients have been studied very little in Mexico. The aim of the present study was to describe those findings. MATERIALS AND METHODS: A prospective cohort study was conducted that included patients with hospital-acquired diarrhea associated with Clostridium difficile diagnosed through polymerase chain reaction. The hypervirulent NAP027 strain was also determined. The clinical and endoscopic findings in the study patients, as well as the variables associated with severity, were analyzed. RESULTS: Of the 127 patients with hospital-acquired diarrhea, 97 were excluded from the study due to lack of colonoscopy. The remaining 39 study patients had a mean age of 48 years, and their most common signs/symptoms were abdominal pain (49%), mucus in stools (41%), and blood in stools (10%). The most common alterations in the laboratory results were leukocytosis in 49%, fecal leukocytes (61%), and hypoalbuminemia (67%). The main risk factor was antibiotic use in 62%, and ceftriaxone was the most widely used. The hypervirulent strain was present in 54% of the cases. Endoscopic abnormalities were found in 87% of the patients. Thirty-eight percent presented with pseudomembranous colitis, with lesions in the left colon in 53%, and in the right colon in 13%. No association was found between proton-pump inhibitor use and Clostridium difficile-associated diarrhea. There was a significant association between hypoalbuminemia (< 3.3g/dL) and a greater risk for severe colitis, with a RR of 8.2 (p=0.008). CONCLUSIONS: Pseudomembranous colitis lesions associated with the hypervirulent Clostridium difficile strain were predominant in the left colon. Hypoalbuminemia was a significant severity predictor.

CCR5 deficiency predisposes to fatal outcome in influenza virus infection.

Influenza epidemics affect all age groups, although children, the elderly and those with underlying medical conditions are the most severely affected. Whereas co-morbidities are present in 50% of fatal cases, 25-50% of deaths are in apparently healthy individuals. This suggests underlying genetic determinants that govern infection severity. Although some viral factors that contribute to influenza disease are known, the role of host genetic factors remains undetermined. Data for small cohorts of influenza-infected patients are contradictory regarding the potential role of chemokine receptor 5 deficiency (CCR5-Δ32 mutation, a 32 bp deletion in the CCR5 gene) in the outcome of influenza virus infection. We tested 171 respiratory samples from influenza patients (2009 pandemic) for CCR5-Δ32 and evaluated its correlation with patient mortality. CCR5-Δ32 patients (17.4%) showed a higher mortality rate than WT individuals (4.7%; P = 0.021), which indicates that CCR5-Δ32 patients are at higher risk than the normal population of a fatal outcome in influenza infection.

Immune-mediated hepatitis: Basic concepts and treatment.

Immunotherapy with immune checkpoint inhibitors (ICIs) has revolutionized advanced cancer management. Nevertheless, the generalized use of these medications has led to an increase in the incidence of adverse immune-mediated events and the liver is one of the most frequently affected organs. Liver involvement associated with the administration of immunotherapy is known as immune-mediated hepatitis (IMH), whose incidence and clinical characteristics have been described by different authors. It often presents as mild elevations of amino transferase levels, seen in routine blood tests, that spontaneously return to normal, but it can also manifest as severe transaminitis, possibly leading to the permanent discontinuation of treatment. The aim of the following review was to describe the most up-to-date concepts regarding the epidemiology, diagnosis, risk factors, and progression of IMH, as well as its incidence in different types of common cancers, including hepatocellular carcinoma. Treatment recommendations according to the most current guidelines are also provided.

Position paper on perioperative management and surgical risk in the patient with cirrhosis.

INTRODUCTION: Management of the patient with cirrhosis of the liver that requires surgical treatment has been relatively unexplored. In Mexico, there is currently no formal stance or expert recommendations to guide clinical decision-making in this context. AIMS: The present position paper reviews the existing evidence on risks, prognoses, precautions, special care, and specific management or procedures for patients with cirrhosis that require surgical interventions or invasive procedures. Our aim is to provide recommendations by an expert panel, based on the best published evidence, and consequently ensure timely, quality, efficient, and low-risk care for this specific group of patients. RESULTS: Twenty-seven recommendations were developed that address preoperative considerations, intraoperative settings, and postoperative follow-up and care. CONCLUSIONS: The assessment and care of patients with cirrhosis that require major surgical or invasive procedures should be overseen by a multidisciplinary team that includes the anesthesiologist, hepatologist, gastroenterologist, and clinical nutritionist. With respect to decompensated patients, a nephrology specialist may be required, given that kidney function is also a parameter involved in the prognosis of these patients.

BK polyomavirus genotyping at inter- and intra-patient level in Spain.

BK polyomavirus (BKV) is classified into four subtypes based on nucleotide variation of a 287 bp typing region in the VP1 protein. Most studies show that subtype I is predominant in different geographic settings, followed by subtype IV. However, BKV subtypes II and III are detected at low rates. In Spain, the prevalence of each subtype is not well known. The aim of this study was to identify the BKV subtypes from a selection of different types of patients and to determine whether different subtypes could be infecting the same patient. A hundred and twenty nine BKV-positive urine samples were selected to amplify and sequence the typing region. Plasma specimens collected at the same time as the urine samples were also studied in 34 patients. A phylogenetic analysis and a study of substitutions in the VP1 protein were carried out with the sequences obtained. Subtype I was the predominant subtype detected in urine (61.2%) and plasma (38.2%) samples followed by subtype II. The analysis of paired samples showed that the subtype found in urine was different from that found in plasma in 10 patients. Fourteen BKV variants based on substitutions in VP1 were identified. The finding of compartmentalized infections involving different subtypes at different sites in some patients might mean specific and different selective pressure in each tissue. The potential involvement in the viral cycle of the different BKV variants found should be analyzed.

Current vision on diagnosis and comprehensive care in hepatic encephalopathy.

The first clinical guidelines on hepatic encephalopathy were published in 2009. Almost 14 years since that first publication, numerous advances in the field of diagnosis, treatment, and special condition care have been made. Therefore, as an initiative of the Asociación Mexicana de Gastroenterología A.C., we present a current view of those aspects. The manuscript described herein was formulated by 24 experts that participated in six working groups, analyzing, discussing, and summarizing the following topics: Definition of hepatic encephalopathy; recommended classifications; epidemiologic panorama, worldwide and in Mexico; diagnostic tools; conditions that merit a differential diagnosis; treatment; and primary and secondary prophylaxis. Likewise, these guidelines emphasize the management of certain special conditions, such as hepatic encephalopathy in acute liver failure and acute-on-chronic liver failure, as well as specific care in patients with hepatic encephalopathy, such as the use of medications and types of sedation, describing those that are permitted or recommended, and those that are not.

BK virus infection in human immunodeficiency virus-infected patients.

The aim of this study is to evaluate the prevalence of BK virus (BKV) infection in HIV-positive patients receiving highly active antiretroviral therapy (HAART) in our hospital. The presence of BKV was analysed in urine and plasma samples from 78 non-selected HIV-infected patients. Clinical data were recorded using a pre-established protocol. We used a nested PCR to amplify a specific region of the BKV T-large antigen. Positive samples were quantified using real-time PCR. Mean CD4 count in HIV-infected patients was 472 cells/mm3 and median HIV viral load was <50 copies/mL. BKV viraemia was detected in only 1 HIV-positive patient, but 57.7% (45 out of 78) had BKV viruria, which was more common in patients with CD4 counts>500 cells/mm3 (74.3% vs 25.7%; p=0.007). Viruria was present in 21.7% of healthy controls (5 out of 23 samples, p=0.02). All viral loads were low (<100 copies/mL), and we could not find any association between BKV infection and renal or neurological manifestations. We provide an update on the prevalence of BKV in HIV-infected patients treated with HAART. BKV viruria was more common in HIV-infected patients; however, no role for BKV has been demonstrated in this population.

Evaluation and management of emergencies in the patient with cirrhosis.

The approach to and management of critically ill patients is one of the most versatile themes in emergency medicine. Patients with cirrhosis of the liver have characteristics that are inherent to their disease that can condition modification in acute emergency treatment. Pathophysiologic changes that occur in cirrhosis merit the implementation of an analysis as to whether the overall management of a critically ill patient can generally be applied to patients with cirrhosis of the liver or if they should be treated in a special manner. Through a review of the medical literature, the available information was examined, and the evidence found on the special management required by those patients was narratively synthesized, selecting the most representative decompensations within chronic disease that require emergency treatment.

Effectiveness of the 2010/11 seasonal trivalent influenza vaccine in Spain: preliminary results of a case-control study.

We present preliminary results of a case-control study to estimate influenza vaccine effectiveness in Spain, from week 50 of 2010 to week 6 of 2011. The adjusted effectiveness of the vaccine in preventing laboratory-confirmed influenza due to any type of influenza virus was 50% (95% CI: -6 to 77%) for the trivalent seasonal vaccine and 72% (95% CI: 7 to 92%) for both trivalent seasonal and monovalent pandemic vaccines, suggesting a protective effect of seasonal vaccination lower than that reported for the previous season.

Evidences and drivers of ocean deoxygenation off Peru over recent past decades.

Deoxygenation is a major threat to the coastal ocean health as it impacts marine life and key biogeochemical cycles. Understanding its drivers is crucial in the thriving and highly exploited Peru upwelling system, where naturally low-oxygenated subsurface waters form the so-called oxygen minimum zone (OMZ), and a slight vertical shift in its upper limit may have a huge impact. Here we investigate the long-term deoxygenation trends in the upper part of the nearshore OMZ off Peru over the period 1970-2008. We use a unique set of dissolved oxygen in situ observations and several high-resolution regional dynamical-biogeochemical coupled model simulations. Both observation and model present a nearshore deoxygenation above 150 m depth, with a maximum trend of - 10 µmol kg-1 decade1, and a shoaling of the oxycline depth (- 6.4 m decade-1). Model sensitivity analysis shows that the modeled oxycline depth presents a non-significant (+ 0.9 m decade-1) trend when remote forcing is suppressed, while a significant oxycline shoaling (- 3 m decade-1) is obtained when the wind variability is suppressed. This indicates that the nearshore deoxygenation can be attributed to the slowdown of the near-equatorial eastward currents, which transport oxygen-rich waters towards the Peruvian shores. The large uncertainties in the estimation of this ventilation flux and the consequences for more recent and future deoxygenation trends are discussed.

The Mexican consensus on alcoholic hepatitis. / Consenso Mexicano de hepatitis alcohólica.

Alcoholic hepatitis is a frequent condition in the Mexican population. It is characterized by acute-on-chronic liver failure, important systemic inflammatory response, and multiple organ failure. The severe variant of the disease implies elevated mortality. Therefore, the Asociación Mexicana de Gastroenterología and the Asociación Mexicana de Hepatología brought together a multidisciplinary team of health professionals to formulate the first Mexican consensus on alcoholic hepatitis, carried out utilizing the Delphi method and resulting in 37 recommendations. Alcohol-related liver disease covers a broad spectrum of pathologies that includes steatosis, steatohepatitis, different grades of fibrosis, and cirrhosis and its complications. Severe alcoholic hepatitis is defined by a modified Maddrey's discriminant function score ≥ 32 or by a Model for End-Stage Liver Disease (MELD) score equal to or above 21. There is currently no specific biomarker for its diagnosis. Leukocytosis with neutrophilia, hyperbilirubinemia (> 3 mg/dL), AST > 50 U/l (< 400 U/l), and an AST/ALT ratio > 1.5-2 can guide the diagnosis. Abstinence from alcohol, together with nutritional support, is the cornerstone of treatment. Steroids are indicated for severe disease and have been effective in reducing the 28-day mortality rate. At present, liver transplantation is the only life-saving option for patients that are nonresponders to steroids. Certain drugs, such as N-acetylcysteine, granulocyte-colony stimulating factor, and metadoxine, can be adjuvant therapies with a positive impact on patient survival.

The Mexican consensus on the diagnosis, treatment, and prevention of NSAID-induced gastropathy and enteropathy. / Consenso mexicano sobre diagnóstico, prevención y tratamiento de la gastropatía y enteropatía por antiinflamatorios no esteroideos.

More than 30 million persons worldwide take nonsteroidal anti-inflammatory drugs (NSAIDs) on a daily basis, and annual consumption is increasing. In addition to their analgesic and anti-inflammatory properties, NSAIDs also produce well-known gastrointestinal adverse events. There is no consensus in Mexico on the diagnosis, treatment, and prevention of NSAID-induced gastropathy and enteropathy, and so the Asociación Mexicana de Gastroenterología brought together a group of experts to establish useful recommendations for the medical community. Thirty-three recommendations were formulated in the present consensus, highlighting the fact that the risk for NSAID-induced gastrointestinal toxicity varies according to the drug employed and its pharmacokinetics, which should be taken into account at the time of prescription. The risk factors for gastroduodenal complications due to NSAIDs are: a history of peptic ulcer, age above 65 years, high doses of NSAIDs, Helicobacter pylori infection, and the presence of severe comorbidities. The symptoms and gastroduodenal damage induced by NSAIDs vary, ranging from an asymptomatic course to the presentation of iron-deficiency anemia, bleeding, stricture, and perforation. Capsule endoscopy and enteroscopy are direct diagnostic methods in NSAID enteropathy. Regarding prevention, the minimum dose of an NSAID needed to achieve the desired effect, administered for the shortest period of time, is the recommendation. Finally, proton pump inhibitors are the gold standard for the prophylaxis and treatment of gastroduodenal effects, but they are not useful in enteropathy.

BK virus in liver transplant recipients: a prospective study.

BACKGROUND: BK virus (BKV) is a polyomavirus that is associated with nephropathy and graft loss among kidney transplant recipients. The role of BK virus in nonrenal solid organ transplant recipients has not been clearly established; only anecdotal case reports have been published. METHODS: From August 2005 to September 2007, all liver transplant (OLT) recipients who gave their consent were enrolled in this prospective longitudinal study. BK viral load was measured using real-time quantitative polymerase chain reaction assays of urine and plasma, using samples collected at week 1 and months 1, 3, 6, 9, 12, 15, 18, 21, and 24 posttransplantation. We also collected demographic and clinical data, including serum creatinine and immunosuppressive therapy. RESULTS: The mean age of the 62 patients was 51.4 years including 14 (22.5%) women. Hepatitis C infection was present in 24 patients (38.7%). BK viruria was detected in 14.5% of 290 samples, corresponding to 13 patients (21%). BK viremia was detected in 5.1% of 317 samples, corresponding to 11 patients (18%). Almost all cases of BK viremia (91%) occurred in the first 3 months after OLT. BKV viremia was more common among patients experiencing a rejection episode (10.6 vs 40%, P = .01). We did not observe a relationship between single episodes of BKV replication and renal function: median plasma creatinine 1.1 mg/dL in patients without versus 1.2 mg/dL with BKV viremia. The three patients with persistent viremia displayed renal insufficiency; one of them died due to multiorgan failure of unknown origin. CONCLUSIONS: BKV is frequently detected in OLT recipients (viruria 21% and viremia 18%) early after transplantation. It is more common among patients with rejection episodes. Persistent BKV viremia may be related to renal dysfunction in OLT patients.

Extrahepatic complications of non-alcoholic fatty liver disease: Its impact beyond the liver. / Complicaciones extrahepáticas de la enfermedad por hígado graso no alcohólico: impacto más allá del hígado.

Non-alcoholic fatty liver disease (NAFLD) is currently one of the main causes of chronic liver disease in Western countries, with a 25% prevalence reported in the general population worldwide. Visceral adiposity and liver fat promote a state of systemic inflammation, predisposing individuals with NAFLD to the extrahepatic pathologies of cardiovascular disease (the most common cause of death in patients with NAFLD), diabetes mellitus, chronic kidney disease, hypothyroidism, polycystic ovary syndrome, obstructive sleep apnea, and an increased risk for presenting with gastrointestinal and extraintestinal neoplasias. Different mechanisms between NAFLD and its association with extrahepatic diseases have been reported, and lipotoxicity is the main cause of inflammatory pathway activation that results in extrahepatic tissue damage.

Consensus on the prevention, diagnosis, and treatment of Clostridium difficile infection. / Consenso sobre prevención, diagnóstico y tratamiento de la infección por Clostridium difficile.

In recent decades, Clostridium difficile infection (CDI) has become a worldwide health problem. Mexico is no exception, and therefore the Asociación Mexicana de Gastroenterología brought together a multidisciplinary group (gastroenterologists, endoscopists, internists, infectious disease specialists, and microbiologists) to carry out the "Consensus on the prevention, diagnosis, and treatment of Clostridium difficile infection", establishing useful recommendations (in relation to the adult population) for the medical community. Said recommendations are presented herein. Among them, it was recognized that CDI should be suspected in subjects with diarrhea that have a history of antibiotic and/or immunosuppressant use, but that it can also be a community-acquired infection. A 2-step diagnostic algorithm was proposed, in which a highly sensitive test, such as glutamate dehydrogenase (GDH), is first utilized, and if positive, confirmed by the detection of toxins through immunoassay or nucleic acid detection tests. Another recommendation was that CDI based on clinical evaluation be categorized as mild-moderate, severe, and complicated severe, given that such a classification enables better therapeutic decisions to be made. In mild-moderate CDI, oral vancomycin is the medication of choice, and metronidazole is recommended as an alternative treatment. In addition, fecal microbiota transplantation was recognized as an efficacious option in patients with recurrence or in the more severe cases of infection, and surgery should be reserved for patients with severe colitis (toxic megacolon), in whom all medical treatment has failed.

Shoaling in juvenile guppies: the effects of body size and shoal size.

While factors affecting shoal mate choice have been examined extensively in adult guppies (Poecilia reticulata), few studies have focused on the shoaling behavior of juveniles. In this study, juvenile guppies were tested for their ability to shoal as well as their response to shoal mates of different body size and to shoals with different numbers of individuals. In dichotomous choice tests, 10-day-old guppies (mean body length=8.83 mm), 30-day-old guppies (13.17 mm) and 50-day-old guppies (18.6mm) were given the opportunity to swim near shoals of five fish or an empty chamber. In most cases, the juvenile fish demonstrated shoaling behavior, swimming near a group of fish rather than an empty chamber, regardless of the age of the stimulus shoal. When presented with two shoals, one of similar age and body size and one of dissimilar age and body size, only the 50-day-old guppies showed a significant preference for the age-matched shoal. Similarly, when choosing between a large shoal and a small shoal, only the 50-day-old guppies spent significantly more time near the larger shoal. Thus, while juveniles at each age shoaled, only 50-day-old fish demonstrated the shoal mate discrimination seen in adult fish.

[Rupture of the superficial dorsal vein of the penis]. / Rotura de la vena dorsal superficial de pene.

Rupture of the superficial dorsal vein of the penis during intercourse is an unfrequented entity that makes the differential diagnosis with other acute penile injuries that may require surgical exploration necessary. We report the case of a 58-year-old male patient with 24-hours evolution painless haematoma after intercourse; its evolution and characteristic physical exploration enable us to adopt a conservative approach that resulted in complete recovery without sequels.