Regional variation in the organization and connectivity of the first synapse in the primate night vision pathway.

Sensitivity of primate daylight vision varies across the visual field. This is attributed to regional variations in cone photoreceptor density and synaptic connectivity of the underlying circuitry. In contrast, we have limited understanding of how synapse organization of the primate night vision pathway changes across space. Using serial electron microscopy, we reconstructed the first synapse of the night vision pathway between rod photoreceptors and second-order neurons, at multiple locations from the central part of the primate retina, fovea, to the periphery. We find that most facets of the rod synapse connectivity vary across retinal regions. However, rod synaptic divergence and convergence patterns do not change in the same manner across locations. Moreover, patterns of rod synapse organization are tightly correlated with photoreceptor density. Such regional heterogeneities revise the connectivity diagram of the primate rod synapse which will shape synapse function and sensitivity of the night vision pathway across visual space.

Risk Factors Associated with Failure of Toe Amputation in Diabetic Foot Infections.

We aim to identify the factors associated with the failure of amputation of one to three toes (index toe amputation) in patients with diabetes and foot infection. We conducted a retrospective cohort of 175 patients with diabetes who were hospitalized for moderate to severe foot infection and underwent amputation of one to three toes. A Poisson regression model was used to determine the prevalence ratio (PR) as a measure of association. The mean age was 63.3 ± 11.4 years. Fifty-three patients presented failure after undergoing toe amputation (30.3%). Multivariate analysis, adjusted for age and sex, showed the following significant variables: severe infection (PR: 1.78; 95% confidence interval [CI]: 1.14-2.78; P = 0.011), infection by Escherichia coli (PR: 2.21; 95% CI: 1.42-3.43; P < 0.001), infection by Pseudomonas aeruginosa (PR: 2.11; 95% CI: 1.29-3.43; P = 0.003) and prothrombin time (PR: 1.13; 95% CI: 1.05-1.21; P = 0.001), obesity (PR: 0.58; 95% CI: 0.37-0.93; P = 0.024), and haemoglobin value (PR: 0.92; 95% CI: 0.86-0.99; P = 0.023). About one-third of patients who underwent amputation of one to three toes for diabetic foot infection presented a failure and required a more proximal surgery. Severe infections, isolation of Pseudomonas aeruginosa and Escherichia coli, and prolonged prothrombin time were associated with a higher prevalence of failure. However, obesity and an elevated haemoglobin level were associated with a lower prevalence of failure.

Seroprevalence and detection of bovine leukosis virus in semen from breeding bulls in Costa Rica.

Bovine leukemia virus (BLV) causes enzootic bovine leukosis, a persistent infection and the most important neoplastic disease in cattle. It is spread primarily by transferring infected lymphocytes through blood from carriers to healthy animals. The present study is aimed at determining the seropositivity of BLV in breeding bulls from Costa Rica and at detecting for the first time in the country BLV DNA in bull semen. Between May 2011 and August 2018, 379 blood and 133 semen samples were collected from bulls distributed in 118 farms. The serum was analyzed by an enzymatic immunoassay and the semen by polymerase chain reaction and sequencing. BLV seropositivity was 43.5% (165/379), while 64.4% (76/118) of the farms had positive reactors. Holstein (75.7%) and Jersey (73.0%) breeds showed the highest seropositivity. In addition, Bos taurus bulls (68.1%), older than seven years (50.0%), and those belonging to dairy farms (75.5%) had higher seropositivity compared to Bos indicus (17.7%), younger than seven years (42.2%), and those from beef farms (15.5%), respectively. Moreover, Bos taurus bulls had a higher risk of being seropositive than Bos indicus (OR = 3.4; 95% CI: 1.7-6.8). BLV DNA was found in one semen sample (2.5%; 1/40) from a seropositive bull. The importance of serum and molecular BLV screening in semen samples and the potential role of some risk factors associated with the disease, such as the bull's age, genotype, and type of livestock productive system, is argued in the present report.

Mortalidad de pacientes internados por pie diabético en un hospital de Costa Rica (2017-2019) / Mortality of inpatients due to diabetic foot in a hospital in Costa Rica (2017-2019)

Resumen Objetivo: Identificar factores clínicos y sociodemográficos asociados a la mortalidad en los pacientes internados por pie diabético, en la Unidad de Pie Diabético del Hospital San Juan de Dios de Costa Rica, del año 2017 al 2019. Materiales y métodos: Estudio de cohorte retrospectivo con 238 pacientes, seguidos desde su internamiento hasta la muerte o al 31 de diciembre del 2021 aún vivos. Análisis descriptivo a variables sociodemográficas, clínicas y causas de muerte. Modelo de riesgos proporcionales de Cox para todas las causas de muerte, y otro exclusivo para muerte por causa cardiovascular. Tiempos de supervivencia se analizan por curvas de Kaplan-Meier, con la prueba de log-Rank para comparar curvas. Resultados: Mayoría de los fallecidos eran hombres, no contaban con pareja, residían en zona urbana o predominantemente urbana, de 15 años o más de ser diabéticos, hipertensos, con enfermedad arterial periférica, anemia, hemoglobina glicosilada inadecuada y obesidad. La tasa de mortalidad fue 23,53%, y la principal causa de muerte fue la enfermedad cardiovascular (35,70 %). Las variables asociadas con mortalidad por todas las causas, ajustadas por edad y sexo fueron: ausencia de pareja (HR: 13,09; IC 95 %: 4,04-42,31), obesidad (HR: 2,89; IC 95 %: 1,59-5,27), enfermedad arterial periférica (HR: 2,26; IC 95 %: 1,25-4,09), años de evolución de la diabetes mellitus ≥ 15 años (HR: 1,99; IC 95 %: 1,04-3,82). A su vez, para mortalidad cardiovascular fueron: obesidad (HR: 6,42; IC 95 %: 2,07-19,87), enfermedad arterial periférica (HR: 3,88; IC 95 %: 1,39-10,79) y cardiopatía (HR: 4,11; IC 95 %: 1,62-10,46). Conclusiones: Años de evolución de la diabetes mellitus mayor o igual a 15 años, no contar con pareja; la obesidad y enfermedad arterial periférica se asoció a mortalidad por todas las causas. Respecto a muerte por enfermedad cardiovascular, las variables asociadas fueron obesidad, enfermedad arterial periférica y cardiopatía.

Abstract Objective: To identify clinical and sociodemographic factors associated with mortality in patients hospitalized for diabetic foot, in the Diabetic Foot Unit of the San Juan de Dios Hospital in Costa Rica, from 2017 to 2019. Materials and methods: A retrospective cohort study with 238 patients, followed from hospitalization until death or until December 31, 2021, still alive. A descriptive analysis is made of the sociodemographic, clinical, and cause of death variables. A Cox proportional hazards model is run for all causes of death, and another exclusively for death from cardiovascular causes. Survival times are analyzed using Kaplan-Meier curves, with the log-rank test for comparison. Results: Most of the deceased were men, did not have a partner, lived in urban or predominantly urban areas, were 15 years or older, diabetic, hypertensive, with peripheral arterial disease, anemia, inadequate glycosylated hemoglobin, and obesity. The mortality rate was 23,53%, and cardiovascular disease was the main cause of death (35,70%). The variables associated with all-cause mortality, adjusted for age and sex were: absence of a partner (HR: 13,09; 95% CI: 4,04-42,31), obesity (HR: 2,89; 95% CI %: 1,59-5,27), peripheral arterial disease (HR: 2,26; CI 95%: 1,25-4,09), years of evolution of diabetes mellitus ≥ 15 years (HR: 1,99; CI 95 %: 1,04-3,82). In turn, for cardiovascular mortality were: obesity (HR: 6,42; 95% CI: 2,07-19,87), peripheral arterial disease (HR: 3,88; 95% CI: 1,39-10,79) and heart disease (HR: 4,11; 95% CI: 1,62-10,46). Conclusions: Evolution of diabetes mellitus greater than or equal to 15 years, not having a partner, obesity and peripheral arterial disease were associated with all-cause mortality. Regarding death from cardiovascular disease, the associated variables were obesity, peripheral arterial disease, and heart disease.

Highly Effective Frontal Stunning Procedure Using a Pneumatic Penetrating Captive Bolt in Water Buffaloes.

An effective frontal stunning procedure in water buffaloes was assessed using a pneumatic penetrating captive bolt (PPCB) with high air pressure. The study contemplated two phases; first, 352 buffaloes and 168 post-mortem heads were evaluated to determine the most effective anatomical site for stunning. Then, the second phase (n = 182) was used to validate the stunning procedure at the discovered anatomical site in the first phase, which was located 8 cm dorsal above the middle of the forehead on an "X" formed between the eyes and the base of the contralateral horns, and 2 cm lateral, avoiding the midline, where the skull tended to narrow. A total of 95.1% of buffaloes received effective stunning at the first shot with evidence of the presence of collapse, absence of rhythmic breathing, and absence of ocular reflexes (corneal and palpebral). There were no differences in the stunning efficacy by sex, breed, or skull thickness. These findings demonstrated that stunning with a PPCB at pressures of 1379-1516.8 KPa (200-220 pounds per square inch (psi)) in the site reported here produces a highly effective stunning at the first shot in water buffaloes.

Green Space Exposure and Obesity in the Mexican Adult Population.

Green space or natural vegetation may reduce obesity risk by increasing opportunities for physical activity or reducing stress and exposure to other pollutants. Obesity prevalence in Mexico is ranked among the highest in the world. However, research on the association between green space and obesity in Mexico is lacking. We used data from the National Nutrition Survey in Mexico (2018-2019), a nationally representative sample of Mexican adults. The analytical sample included participants between 20-59 years of age (n = 12,631). We assessed exposure to green space using a 30 m resolution Landsat satellite Normalized Difference Vegetation Index (NDVI) from 2018. Linear regression models examined associations between NDVI and body mass index (BMI), adjusting for confounders. The mean age of the study sample was 38 (SD 0.19) years. Participants living in areas with the highest green space exposure had the lowest education level (53.51%) and socioeconomic status (28.38%) and were located in central (33.01%), south (30.37%), and rural areas (21.05%). Higher residential exposure to green space was associated with a mean decrease in BMI of -1.1 kg/m2 (95% CI: -1.59, -0.68). This is one of the first studies in Latin America to suggest a protective association between green space and obesity among Mexican adults.

Biological evaluation of a mechanical ventilator that operates by controlling an automated manual resuscitator. A descriptive study in swine.

The Covid-19 outbreak challenged health systems around the world to design and implement cost-effective devices produced locally to meet the increased demand of mechanical ventilators worldwide. This study evaluates the physiological responses of healthy swine maintained under volume- or pressure-controlled mechanical ventilation by a mechanical ventilator implemented to bring life-support by automating a resuscitation bag and closely controlling ventilatory parameters. Physiological parameters were monitored in eight sedated animals (t0) prior to inducing deep anaesthesia, and during the next six hours of mechanical ventilation (t1-7). Hemodynamic conditions were monitored periodically using a portable gas analyser machine (i.e. BEecf, carbonate, SaO2, lactate, pH, PaO2, PaCO2) and a capnometer (i.e. ETCO2). Electrocardiogram, echocardiography and lung ultrasonography were performed to detect in vivo alterations in these vital organs and pathological findings from necropsy were reported. The mechanical ventilator properly controlled physiological levels of blood biochemistry such as oxygenation parameters (PaO2, PaCO2, SaO2, ETCO2), acid-base equilibrium (pH, carbonate, BEecf), and perfusion of tissues (lactate levels). In addition, histopathological analysis showed no evidence of acute tissue damage in lung, heart, liver, kidney, or brain. All animals were able to breathe spontaneously after undergoing mechanical ventilation. These preclinical data, supports the biological safety of the medical device to move forward to further evaluation in clinical studies.

Consenso mexicano para el diagnóstico y tratamiento de la trombastenia de Glanzmann / Mexican consensus on the diagnosis and treatment of Glanzmann thrombasthenia

Resumen Las plaquetas tienen un papel central en diferentes escenarios fisiológicos, incluyendo la hemostasia; se unen unas con otras en la agregación plaquetaria, lo cual permite formar un coágulo plaquetario. Para que la agregación sea apropiada se requiere del complejo glicoproteico IIb/IIIa (GPIIb/IIIa) en la superficie plaquetaria. Toda alteración funcional plaquetaria, hereditaria o adquirida, impide la formación adecuada del coágulo y se manifiesta como hemorragia. Las enfermedades plaquetarias hereditarias son raras y, hasta recientemente, fueron ignoradas. Una de las más reconocidas y estudiadas es la trombastenia de Glanzmann (TG), entidad en la cual el número de plaquetas puede ser normal pero la función está alterada. Es un padecimiento autosómico y recesivo que causa hemorragia de diferente intensidad toda la vida y en la cual el problema radica en precisamente en la GPIIb/IIIa. Las hemorragias son típicamente mucocutáneas: equimosis, púrpura, epistaxis, gingivorragia; menos frecuentes son la hemorragia gastrointestinal, hemartrosis o en sistema nervioso central. La hiperpolimenorrea es común en las mujeres y llega a ser tan importante que amerita transfusiones en la menarca. La TG afecta a todos los grupos étnicos y su prevalencia varía entre 1/40,000 y 1/400,000. A pesar de esta información acerca de la TG en el mundo, hay pocas guías o recomendaciones basadas en la opinión de expertos y experiencias unicéntricas. En México la TG es rara y no se cuenta con una recomendación general para su diagnóstico y tratamiento. El objetivo de este documento fue establecer un consenso y hacer sugerencias generales para su diagnóstico y tratamiento.

Abstract Platelets have a central role in several physiological scenarios including hemostasis. Platelets bind each other during platelet aggregation allowing the proper formation of the clot; to be appropriate, platelet aggregation requires the glycoproteic complex IIb/IIIa (GPIIb/IIIa). Every platelet function abnormality both, congenital or acquired, impedes clot formation and favors bleeding episodes. Hereditary platelet abnormalities are rare and, until recently, they were almost ignored. Among these disorders, Glanzmann Thrombasthenia (GT) is a widely recognized abnormality in which platelet counts may be normal, but their function is affected. GT is an autosomal, recessive disease that causes life-long bleeding of different intensity. Main biochemical abnormality resides in GPIIb/IIIa. Bleeding is typically mucocutaneous: easy bruising, purpura, and nose and gum bleeds; less frequently are gastrointestinal bleeds, hemarthrosis, or intracranial. Menorrhagia and hyperpolymenorrhea are common findings in in women and may be the cause of anemia requiring blood transfusions at fertile age. GT affects all ethnic groups and its prevalence ranges between 1/40,000 to 1/400,000. Despite this worldwide information regarding GT, only a few guidelines and recommendations have been published, most of them based on expert opinions. In Mexico, GT is rare and there is not a general recommendation regarding its diagnosis and treatment. The aim of this document was to establish a consensus to suggest a general guideline for the diagnosis and treatment of GT in Mexico.

Consenso de leucemia mieloide aguda en México / Mexican consensus in acute myeloid leukemia in Mexico

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Abstract Acute myeloid leukemia (AML) comprises a heterogeneous group of hematopoietic cell neoplasms of myeloid lineage that arise from the clonal expansion of their precursors in the bone marrow, interfering with cell differentiation, leading to a syndrome of bone marrow failure. AML is a consequence of genetic and epigenetic changes (point mutations, gene rearrangements, deletions, amplifications, and arrangements in epigenetic changes that influence gene expression) in hematopoietic precursor cells, which create a clone of abnormal cells that are capable of proliferating but cannot differentiate into mature hematopoietic cells or undergo programmed cell death. The diagnosis requires more than 20% myeloid blasts in the bone marrow and certain cytogenic abnormalities. Treatment will depend on age, comorbidities, and cytogenetic risk among the most frequent.

Backfat Thickness Does Affect the Restoration of Ovarian Activity Postpartum in Different Breeding Programs in Zebu Cattle.

The backfat thickness (BFT) was used to forecast the onset of ovarian activity and predict the calf growth. Eighty Brahman cows with their calves were allocated in two groups of 40 distributed in 4 months according to the month of calving, starting in March and finishing in June. One was synchronized and inseminated at fixed time following by natural mating (TAI+NM); whilst the other only by natural mating (NM). The programs started at 60 ± 5 days postpartum and ended 60 days later. From day 30 postpartum, serial ultrasound examinations and progesterone samples were used to monitor the onset of ovarian activity. The BFT in the rump area was measured by ultrasound from 30 days postpartum and every 15 days thereafter. The weight of the calves was recorded at birth and at weaning on 160 days. The adjusted effect of BFT on ovarian activity and the calves' development was assessed by binomial logistic regression at 30, 60, 75, and 120 days postpartum. The cycling cows averaged higher BFT irrespective of breeding program (P < 0.001). Also, slower changes in BFT were recorded during the follow-up at each time for all cows. However, the former had the higher BFT values from calving to the end of the study (P < 0.001). At 60, 75, and 120 days, the BFT measured, at the preceding time, was the only factor predicting the commencement of cyclicity (P < 0.001). The accumulative pregnancy through time was higher in TAI+NM (P = 0.003). Daily weight gain and weaning weight of the calves born in March was significantly heavier (P < 0.001) than peers born in April, May, or June. The most critical element to forecast the onset of ovarian activity is the monitoring of BFT around calving regardless of the breeding program. BFT to estimate the development of the calves until weaning was unpredictable.

Effects of Season on Donor and Recipient Cows and Calf Performance from Birth to Weaning in Embryo Transfer Programs in the Tropics.

The aim of this study was to assess the seasonal effect of an embryo transfer program in the tropics on the donor response, recipient reproductive performance and calf growth from birth to weaning. This study included five-year records from 145 donors, 1149 embryo transfers (ET) and 609 in calves. The effect of the season (dry or wet) was evaluated at the time of embryo flushing, embryo transfer and birth of the calves. There was a seasonal effect on the yield and quality of the embryos. The number of nonfertilized and transferable good quality embryos increased in the wet season. For the recipients, the probability of pregnancy after an ET decreased by 6% for each year of the dam's age. However, no seasonal effect was found when comparing ET calves with their control group (natural mating-NM), nevertheless, weaning weight was associated with birth body weight, treatment, sex of the calf, season at birth, year of treatment, and dam's age. Calves born by NM had lower average daily gain (ADG), and male calves registered higher gains than females. Likewise, calves born during the rainy season had lower ADG compared with calves born during the dry season. In conclusion, this study shows that seasonal effect is more apparent in donor and calf performance than in the recipients.

Seroprevalence and prevalence of Babesia vogeli in clinically healthy dogs and their ticks in Costa Rica.

Canine babesiosis is a disease caused by a parasite of the genus Babesia which destroys red blood cells. Previous studies have shown the presence of Babesia vogeli in rural areas in Costa Rica using molecular techniques. The objective of the present study was to determine the seroprevalence and prevalence of B. vogeli in clinically healthy dogs and their ticks at the national level, both within and outside the Central Valley. Blood samples and ticks from 482 dogs were collected between June 2011 and May 2014, and analyzed by immunofluorescence assay (IFA) and real-time polymerase chain reaction (qPCR); two protocols of endpoint PCR and sequencing were used to confirm qPCR-positive samples. Seroprevalence of canine babesiosis of 5.3% (24/453) was determined at the national level, specifically 2.0% (5/253) within and 9.5% (19/200) outside the Central Valley, respectively. Real-time PCR determined a global prevalence of B. vogeli of 31.3% (125/400): 21.4% (47/220) within the Central Valley and 43.3% (78/180) outside the Central Valley. The endpoint PCR amplified only 10 of the 125 blood samples identified as positive in qPCR. One sample amplified by endpoint PCR was sequenced and identified as B. vogeli. Twelve canines were identified with past infections, seven canines with active infection, and 111 canines with early infection. Two species of ticks were found with B. vogeli: Rhipicephalus sanguineus sensu lato (n = 40) and Amblyomma ovale (n = 1). The prevalence of canine babesiosis at the national level, both within and outside the Central Valley, is reported here for the first time, determining the presence of the piroplasmid throughout the country, with a higher circulation of the agent outside the Central Valley. Only one species, B. vogeli, was detected in the blood of dogs and their ticks. Therefore, veterinarians should consider using qPCR to determine the presence of the parasite in blood donors and before starting treatment of vector-borne disease in dogs.

Seroprevalence of porcine reproductive and respiratory syndrome virus on swine farms in a tropical country of the Middle Americas: the case of Costa Rica.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant economic losses to the swine industry worldwide. Little is known regarding the epidemiology of this infection in tropical countries. To address this problem in Costa Rica, a seroepidemiological study was carried out in two phases. In the first phase, a pilot study was conducted in nine farms with the clinical diagnosis of PRRSV. In total, 265 pig serum samples were collected from animals ranging in age from 1 to 15 weeks of age. This study aimed to establish the duration of maternal immunity in piglets, to identify the period of viremia, and to determine when seroconversion occurs. In the second phase, a cross-sectional serology study was performed on a representative sample of the Costa Rican national herds in the second phase. The twenty-five selected farms represent all provinces and were classified according to herd size (100 to 2000 sows). In each farm, pigs aged 8, 10, and 12 weeks were sampled, as well as gilts based on the pilot study. In total 1281 pigs were sampled across all 25 farms. The aim of the cross-sectional study was to quantify the seroprevalence of PRRSV in Costa Rican pig farms and to describe its geographical distribution in this tropical country. The prevalence of positive farms was 44% (11/25), and these farms were located in six of the seven provinces of Costa Rica. Overall, 58% (344/596) of the pigs were seropositive to PRRSV. The age of the pigs and the ecozone where farms were located were significantly related with PRRSV seroprevalence in animals and herds, respectively.

Mexican consensus on Hodgkin's lymphoma.

El linfoma de Hodgkin (LH) se debe a la transformación clonal de células originadas en los linfocitos B, lo que genera las células binucleadas patognomónicas de Reed-Sternberg. El LH es una enfermedad de células B con una distribución bimodal, con mayor incidencia en la adolescencia y la tercera década de la vida y un segundo pico en personas mayores de 55 años. Las células del LH clásico habitualmente sufren una reprogramación de la expresión génica, ya que pierden la expresión de la mayoría de los genes típicos de las células B y han adquirido la expresión de múltiples genes que son típicos de otros tipos de células del sistema inmunitario. El algoritmo de tratamiento dependerá si se trata de LH clásico o de predominio linfocítico, si es un estadio temprano con marcadores de pronóstico desfavorables o no, el esquema inicial de manejo y si existe enfermedad voluminosa, entre las variables más relevantes.Hodgkin's lymphoma (HL) is due to the clonal transformation of cells originating from B lymphocytes, generating the pathognomonic binucleate Reed-Sternberg cells. HL is a B cell disease with a bimodal distribution, with higher incidence in adolescence and the third decade of life, showing a second peak in people over 55 years of age. Classic Hodgkin lymphoma cells routinely undergo gene expression reprogramming, as they lose the expression of most of the typical B-cell genes and acquire the expression of multiple genes that are typical of other types of cells in the immune system. The treatment algorithm will depend on whether it is classic or predominantly lymphocytic HL, if it is early stage with unfavorable prognostic markers or not, the initial management regimen, and whether there is bulky disease, among the most relevant variables.

Antimicrobial Resistance and Genetic Diversity of Campylobacter spp. Isolated from Broiler Chicken at Three Levels of the Poultry Production Chain in Costa Rica.

ABSTRACT: Campylobacter spp. are considered the most common bacterial cause of human gastroenteritis, one of the four main causes of diarrheal disease worldwide, and they are one of the main foodborne pathogens causing hospitalizations and deaths. Here, 148 strains of Campylobacter spp. isolated from poultry at farms, processing plants, and retail stores in Costa Rica were examined for resistance to six antibiotics. An agar dilution test was used to determine the MIC and susceptibility profiles against doxycycline, ciprofloxacin, nalidixic acid, enrofloxacin, chloramphenicol, and erythromycin. In addition, a pulsed-field gel electrophoresis analysis was carried out to determine the genotype relatedness of a representative subset of the isolates. Approximately 136 (92%) of the 148 analyzed isolates showed resistance to the tested drugs. Nalidixic acid, ciprofloxacin, and enrofloxacin were the antibiotics for which resistance occurred most frequently (91.2, 85.8, and 85.8%, respectively), followed by doxycycline (25.0%), chloramphenicol (5.4%), and erythromycin (2.7%). The profile conferring only resistance to quinolones was the most frequently found, and only 2.0% of the isolates showed resistance to quinolones and macrolides simultaneously. Results showed a high frequency of resistant Campylobacter spp. strains and evidenced the distribution, selection, and circulation of resistant strains along the poultry chain from farms to consumers. Cross-contamination and resistance seem to play important roles in the dissemination of these strains at specific points of the poultry chain, even when control measures are being taken. The establishment of effective surveillance and control strategies represents an essential tool for foodborne diseases mitigation. The rational use of antibiotics, especially those still showing efficacy, should be a priority in both human and veterinary medicine to contain the progress of this phenomenon and its consequences.

Mexican Consensus on Hodgkin's Lymphoma.

Hodgkin's lymphoma is due to the clonal transformation of cells originating from B lymphocytes, generating the pathognomonic binucleate Reed-Sternberg cells. Hodgkin's lymphoma is a B cell disease with a bimodal distribution, with higher incidence in adolescence and the third decade of life, showing a second peak in people over 55 years of age. Classic Hodgkin lymphoma cells routinely undergo gene expression reprogramming, as they lose the expression of most of the typical B-cell genes and acquire the expression of multiple genes that are typical of other types of cells in the immune system. The treatment algorithm will depend on whether it is classic or predominantly lymphocytic HL, if it is early stage with unfavorable prognostic markers or not, the initial management regimen, and whether there is bulky disease, among the most relevant variables.

El linfoma de Hodgkin (LH) se debe a la transformación clonal de células originadas en los linfocitos B, lo que genera las células binucleadas patognomónicas de Reed-Sternberg. El LH es una enfermedad de células B con una distribución bimodal, con mayor incidencia en la adolescencia y la tercera década de la vida y un segundo pico en personas mayores de 55 años. Las células del LH clásico habitualmente sufren una reprogramación de la expresión génica, ya que pierden la expresión de la mayoría de los genes típicos de las células B y han adquirido la expresión de múltiples genes que son típicos de otros tipos de células del sistema inmunitario. El algoritmo de tratamiento dependerá si se trata de LH clásico o de predominio linfocítico, si es un estadio temprano con marcadores de pronóstico desfavorables o no, el esquema inicial de manejo y si existe enfermedad voluminosa, entre las variables más relevantes.

Acute Promyelocytic Leukemia: A Long-Term Retrospective Study in Mexico.

BACKGROUND: The present retrospective study reviewed acute promyelocytic leukemia (APL) cases recorded in Mexico between January 2007 and January 2017. The primary objective of the study was to evaluate overall survival (OS) in Mexican patients with APL. Secondary objective was to evaluate the impact of induction treatment with different anthracyclines on OS, event-free survival (EFS) and complications in this patient population. METHODS: The medical charts of patients referred to medical institutions in Mexico from January 2007 through January 2017 for the treatment of suspected APL were reviewed retrospectively. Patients aged 15 - 75 years, in whom the diagnosis of APL was confirmed, who had an Eastern Cooperative Group performance status of 0 - 2, and who were eligible for combined treatment with intensive chemotherapy and all-trans retinoic acid (ATRA), were included in the study. Study participants received induction and consolidation treatment with ATRA plus either daunorubicin or idarubicin, followed by 2 years of single-agent ATRA as maintenance therapy. Patients who were unable to pay for ATRA treatment received anthracycline-based induction and consolidation, with methotrexate plus mercaptopurine as maintenance therapy. RESULTS: A total of 360 patients from 21 public and private hospitals were included in the study. The median age of the population was 37 years, and 51% were male. Of the 360 patients, 205 (57%) vs. 155 (43%) received daunorubicin vs. idarubicin as induction treatment for APL. ATRA was administered to 201 (98%) patients in the daunorubicin group vs. 138 (89%) in the idarubicin group (P = 0.001), and was initiated at diagnosis in 92% vs. 73% of recipients, respectively (P = 0.0001). At 150 months, OS and EFS for the entire population were 84% and 79%, respectively. Both OS (90% vs. 76%, P = 0.003) and EFS (85% vs. 72%, P = 0.001) were significantly prolonged in daunorubicin vs. idarubicin recipients. Rates of complications were similar in the two groups. CONCLUSIONS: As arsenic trioxide (ATO) is not currently available in Mexico, anthracycline plus ATRA is the mainstay of treatment for APL here. Our results confirm the efficacy of this strategy, with high OS and EFS rates being observed 12.5 years after diagnosis.

Consensus on hemophilia in Mexico.

Hemophilia is a hemorrhagic disorder with a sex-linked inherited pattern, characterized by an inability to amplify coagulation due to a deficiency in coagulation factor VIII (hemophilia A or classic) or factor IX (hemophilia B). Sequencing of the genes involved in hemophilia has provided a description and record of the main mutations, as well as a correlation with the various degrees of severity. Hemorrhagic manifestations are related to levels of circulating factor, mainly affecting the musculoskeletal system and specifically the large joints (knees, ankles, and elbows). This document is a review and consensus of the main genetic aspects of hemophilia, from the inheritance pattern to the concept of women carriers, physiopathology and classification of the disorder, the basic and confirmation studies when hemophilia is suspected, the various treatment regimens based on infusion of the deficient coagulation factor as well as innovative factor-free therapies and recommendations for the management of complications associated with treatment (development of inhibitors and/or transfusion-transmitted infections), or secondary to articular hemorrhagic events (hemophilic arthropathy). Finally, relevant reviews of clinical and treatment aspects of hemorrhagic pathology characterized by acquired deficiency of FVIII secondary to neutralized antibodies named acquired hemophilia.

La hemofilia es un trastorno hemorrágico con patrón de herencia ligado al sexo, caracterizado por una incapacidad en la amplificación de la coagulación ocasionada por la deficiencia del factor VIII (hemofilia A o clásica) o del factor IX (hemofilia B). La secuenciación de los genes involucrados en la hemofilia ha permitido la descripción y registro de las principales mutaciones, así como la correlación con los diversos grados de severidad. Las manifestaciones hemorrágicas se relacionan con los niveles de factor deficiente circulante, afectando principalmente al sistema musculoesquelético y en particular a las grandes articulaciones (rodillas, tobillos y codos). El presente documento hace una revisión y consenso de los principales aspectos genéticos de la hemofilia, desde el patrón de herencia y el concepto de mujeres portadoras, la fisiopatología y clasificación de la enfermedad, los estudios básicos y de confirmación ante la sospecha de hemofilia, y de los diversos esquemas de tratamiento basados en la infusión del factor de coagulación deficiente hasta las terapias innovadoras libres de factor, así como de las recomendaciones para el manejo de las complicaciones asociadas al tratamiento (desarrollo de inhibidores y/o infecciones transmitidas por transfusión) o secundarias a los eventos hemorrágicos a nivel articular (artropatía hemofílica). La parte final del documento revisa los aspectos clínicos y de tratamiento relevantes de una patología hemorragica caracterizada por la deficiencia adquirida del FVIII mediada por anticuerpos neutralizantes denominada hemofilia adquirida.

Treating Acute Leukemia During the COVID-19 Pandemic in an Environment With Limited Resources: A Multicenter Experience in Four Latin American Countries.

PURPOSE: The COVID-19 pandemic is a colossal challenge for global health; nonetheless, specific subgroups face considerably higher risks for infection and mortality. Among patients with malignant diseases, those with hematologic neoplasms are at a higher risk for poor outcomes. The objective of this study was to register treatment modifications associated with the COVID-19 pandemic and their short-term consequences in Latin America. METHODS: Multicenter, prospective, observational, cohort study including patients older than 14 years from 14 centers in four countries (Mexico, Peru, Guatemala, and Panama) who had a confirmed diagnosis of acute leukemia, and who were undergoing active treatment since the first COVID-19 case in each country until the cutoff on July 15, 2020. RESULTS: We recruited 635 patients. Treatment modifications because of the COVID-19 pandemic were reported in 40.8% of cases. The main reason for such modifications was logistic issues (55.0%) and the most frequent modification was chemotherapy delay (42.0%). A total of 13.1% patients developed COVID-19 disease, with a mortality of 37.7%. Several factors were identified as independently associated with mortality, including a diagnosis of acute myeloid leukemia (odds ratio 2.38 [95% CI, 1.47 to 3.84]; P < .001), while the use of telemedicine was identified as a protective factor (odds ratio 0.36 [95% CI, 0.18 to 0.82]; P = .014). CONCLUSION: These results highlight the collateral damage of COVID-19 in oncology patients.

Epidemiology and Clinical Characteristics of Non-Hodgkin Lymphoma in Mexico.

BACKGROUND: There is no epidemiological registry in Mexico. The information about the epidemiology in our country is obtained by these types of studies, such as multicentric studies. A lot of improvements in the survival in non-Hodgkin lymphoma patients had occurred in the last 20 years. The access to treatment in these types of pathology could change the prognostic factors in Mexican Mestizos patients. The primary objective of the study was to learn what the most frequent histological varieties of non-Hodgkin lymphoma in Mexico are. The secondary objectives included clinical characteristics, treatments used, treatment response, disease-free survival and overall survival. METHODS: A retrospective, descriptive study of consecutive cases was carried out in 14 hospitals across 14 Mexican states with patients diagnosed with non-Hodgkin lymphoma using the World Health Organization (WHO) 2008 criteria. Inclusion criteria included: ≥ 18 years of age, male or female, any clinical stage at diagnosis, who had received any chemotherapy regimen, with a known outcome. Descriptive statistics was performed for all variables, and survival was assessed using Kaplan-Meier curves. RESULTS: Totally, 609 patients were enrolled, of which 545 were B-cell lymphomas and 64 were T-cell lymphomas. Median ages were 61 and 50, respectively. B-cell lymphomas were more common in males with 52.1%, and 65.5% of T-cell lymphomas occurred in females. For B-cell lymphomas, the two most frequent histological subtypes were diffuse large B-cell lymphoma in 63.9%, followed by follicular lymphoma at 18%. Meanwhile, 50% of T-cell lymphomas were of the T/natural killer (NK) subtype, and 87.1% of the patients received a CHOP-like regimen. Radiotherapy was given to 31% of B-cell Lymphomas and 46.9% of T-cell lymphomas. Overall survival at 9 years was 84.6% for B-cell lymphomas, and 73.4% for T-cell lymphomas. CONCLUSIONS: Diffuse large B-cell lymphoma constitutes the most frequent subtype for B-cell lymphomas in Mexico. The most frequent T-cell lymphoma is the NK/T histological subtype.