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Powdery mildew is one of the most severe diseases affecting Cucurbitaceae. We identify the members of Erysiphaceae infecting cucurbits in three producing regions in Mexico. We determined that Golovinomyces ambrosiae (Schwein.) U. Braun & R.T.A. Cook, Neoerysiphe sechii R. Gregorio-Cipriano & D. González, and Podosphaera xanthii (Castagne) U. Braun & Shishkoff infected cultivated and wild cucurbits species or subspecies. Leaf samples showing symptoms and signs of powdery mildew were collected from the northwestern, central western, and eastern regions of Mexico between 2017 and 2020. Species associated with the disease were identified based on morphology and internal transcribed spacer rDNA sequences. All powdery mildew specimens presented only the anamorph. Podosphaera xanthii was the predominant species; it was found in 84.76% of the samples and in 13 out of 14 species or subspecies of cucurbits. Neoerysiphe sechii was found in 15.24% of the samples and in only four cucurbit species from the central western and eastern regions of Mexico. Golovinomyces ambrosiae was documented for the first time in a Cucurbitaceae species (Sicyos deppei G.Don) from central west Mexico. Three new hosts were registered for N. sechii (Cucurbita ficifolia Bouché, Echinopepon milleflorus Naudin, and Sicyos laciniatus L.) and eight for P. xanthii (Cucurbita argyrosperma C.Huber, Cucurbita argyrosperma subsp. sororia (L.H.Bailey) Merrick & D.M.Bates, C. ficifolia, Cucurbita okeechobeensis subsp. martinezii (L.H.Bailey) T.C.Andres & G.P.Nabhan ex T.W.Walte, Cucurbita radicans Naudin, Sechium edule (Jacq.) Sw., S. laciniatus, and S. deppei).

Permanent pacemaker implantation (PPI) represents a rare complication after cardiac surgery, with no uniform agreement on timing and no information on follow-up. A multi-center retrospective study was designed to assess pacemaker dependency (PMD) and long-term mortality after cardiac surgery procedures. Between 2004 and 2016, PPI-patients from 18 centers were followed. Time-to-event data were evaluated with semiparametric regression Cox models and semiparametric Fine and Gray model for competing risk framework. Of 859 (0.90%) PPI-patients, 30% were pacemaker independent (PMI) at 6 months. PMD showed higher mortality compared with PMI (10-year survival 80.1% +/- 2.6% and 92.2% +2.4%, respectively, log-rank p-value < 0.001) with an unadjusted hazard ratio for death of 0.36 (95% CI 0.20 to 0.65, p< 0.001 favoring PMI) and an adjusted hazard ratio of 0.19 (95% CI 0.08 to 0.45, p< 0.001 with PMD as reference). Crude cumulative incidence function of restored PMI rhythm at follow-up at 6 months, 1 year and 12 years were 30.5% (95% CI 27.3% to 33.7%), 33.7% (95% CI 30.4% to 36.9%) and 37.2% (95% CI 33.8% to 40.6%) respectively. PMI was favored by preoperative sinus rhythm with normal conduction (SR) (HR 2.37, 95% CI 1.65 to 3.40, p< 0.001), whereas coronary artery bypass grafting and aortic valve replacement were independently associated with PMD (HR 0.63, 95% CI 0.45 to 0.88, p = 0.006 and HR 0.807, 95% CI 0.65 to 0.99, p = 0.047 respectively). Time-to-implantation was not associated with increased rate of PMI. Although 30% of PPI-patients are PMI after 6 months, PMD is associated with higher mortality at long term. (C) 2020 The Author(s). Published by Elsevier Inc.

Antecedentes y Objetivos: La diversidad de macrolíquenes saxícolas en el estado de Guanajuato es poco conocida. Los escasos datos que existen son menciones de colectas y de especies en páginas electrónicas especializadas. El objetivo de este trabajo fue contribuir, mediante la elaboración de un listado florístico, al conocimiento de la diversidad de macrolíquenes saxícolas en cuatro localidades (cerro “La Bufa”, parque ecológico “El Orito”, carretera panorámica “El Pípila” y Sierra de Santa Rosa de Lima).Métodos: Los ejemplares fueron recolectados y posteriormente determinados mediante el uso de claves especializadas, considerando características morfológicas, anatómicas y químicas. Se apoyó en observaciones al microscopio estereoscópico y compuesto, respuesta a reactivos químicos y, en algunos casos, en la realización de cromatografía de capa fina. Finalmente se revisaron descripciones de las mismas y se cotejaron los ejemplares determinados con aquellos existentes en el herbario EBUM de la Universidad Michoacana de San Nicolás de Hidalgo.Resultados clave: Se presenta una lista de 42 especies para el distrito minero de Guanajuato, que constituyen registros nuevos para las localidades estudiadas; 23 son nuevos registros para el estado de Guanajuato y uno lo es para México.Conclusiones: De las 42 especies, la familia Parmeliaceae es la más representativa del área de estudio, especialmente el género Xanthoparmeliacon nueve especies, de las cuales tres son nuevos registros para el estado de Guanajuato y una de ellas lo es para México. La zona de La Bufa con clima semicálido y la ignimbrita como roca dominante reúne la mayoría de las especies registradas. Las especies de las familias Cladoniaceae, Usneaceae, Ramalinaceae y Stereocaulaceae son representativas de la zona de Santa Rosa de Lima en donde domina un clima húmedo y la toba riolítica como roca principal.

Globally destructive crop pathogens often emerge by migrating out of their native ranges. These pathogens are often diverse at their center of origin, and may exhibit adaptive variation in the invaded range via multiple introductions from different source populations. However, source populations are generally unidentified or poorly studied compared to invasive populations. Phytophthora infestans, the causal agent of late blight, is one of the most costly pathogens of potato and tomato worldwide. Mexico is the center of origin and diversity of P. infestans and migration events out of Mexico have enormously impacted disease dynamics in North America and Europe. The debate over the origin of the pathogen, and population studies of P. infestans in Mexico, have focused on the Toluca Valley, whereas neighboring regions have been little studied. We examined the population structure of P. infestans across central Mexico, including samples from Michoacan, Tlaxcala, and Toluca. We found high levels of diversity consistent with sexual reproduction in Michoacan and Tlaxcala, and population subdivision that was strongly associated with geographical region. We determined that population structure in Central Mexico has contributed to diversity in introduced populations based on relatedness of U.S. clonal lineages to Mexican isolates from different regions. Our results suggest that P. infestans exists as a metapopulation in Central Mexico, and this population structure could be contributing to the repeated re-emergence of P. infestans in the U.S. and elsewhere. This article is protected by copyright. All rights reserved.

En este trabajo se presenta la diversidad de líquenes que se desarrollan sobre árboles nativos e introducidos en las avenidas y áreas verdes, urbanas y suburbanas de Morelia. Se enlistan 49 especies distribuidas en 26 géneros y 10 familias, de las cuales, 39 se registran por primera vez para Morelia e incluyen 27 nuevas citas para el estado de Michoacán y una para México (Hyperphyscia isidiata). Las familias Physciaceae y Parmeliaceae fueron las mejor representadas con el 71% de las especies registradas. El 69,39% presentan talo foliáceo y el 30,61% talo crustáceo; mientras que los líquenes fruticulosos estuvieron ausentes en el área. In this paper is presented the diversity of lichens that develop on the native and introduced trees of the avenues and green areas from the urban and suburban zones of Morelia. 49 species distributed in 26 genera and 10 families were listed. From these, 39 were reported for the first time in Morelia including 27 new reports from Michoacan state and one from Mexico (Hyperphyscia isidiata). Physciaceae and Parmeliaceae families were the best represented with 71% of the recorded species. The 69.39% have foliose tallus and 30.61% crustose tallus; while fruticose lichens were absent in the area.

Background . Mortality after deep sternal wound infection (DSWI) ranges between 5% and 47%. Variables predicting hospital mortality and prolonged hospital stay are still to be assessed. Methods . Among 13,420 patients who underwent cardiac surgery in our institution between 1979 and 1999, DSWI developed in 112 cases (0.8%). Multiple variables were recorded prospectively and analyzed retrospectively as predictors of hospital death and prolonged (>30 days) hospital stay. The analyzed variables were divided into three groups: (1) related to the patient, including demographic variables and preoperative conditions; (2) related to cardiac operation; and (3) related to infection. Predictive variables were assessed by univariate and multivariate logistic regression analysis. Results . Hospital mortality was 16.9%. The hospital stay of the 93 discharged patients ranged between 16 and 180 days (mean 31.3 ± 15.2). Length of cardiac operation, length of stay in intensive care unit, interval between symptoms of DSWI and wound debridement were found to be the most significant predictors of bad outcome following DSWI. Conclusions . In our study demographic variables and preoperative conditions did not affect the prognosis of DSWI. Lower mortality rate and shorter hospital stay could be achieved with earlier and aggressive treatment of DSWI.

Background: The aim of this study was to evaluate the efficacy of preoperative and postoperative therapy with n-3 polyunsaturated fatty acids in reducing the incidence of atrial fibrillation after coronary artery bypass graft surgery. Methods: 201 patients undergoing coronary artery bypass graft surgery were randomized to 1) a control group (105 patients), or 2) n-3 polyunsaturated fatty acids 2 g/day group (96 patients) for at least 5 days before surgery and until hospital discharge. Groups were further subdivided in four subgroups according to the operative technique: “off-pump” or “on-pump”. The primary end point was to evaluate the reduced incidence of postoperative in-hospital atrial fibrillation in the (N-3 PUFA) group. Secondary end points were the impact of the surgical technique on the incidence of postoperative arrhythmia and the impact of n-3 polyunsaturated fatty acids therapy on post-operative hospital length of stay. Results: The overall incidence of post-operative atrial fibrillation was 17.4% (35/201). The arrhythmia occurred in 11.4% (11/96) of the patients in therapy with n-3 polyunsaturated fatty acids and in 22.8% (24/105) in the control groups. In particular, the statistical analysis of subgroups showed a significant reduction of postoperative atrial fibrillation only in the group including patients treated with n-3 polyunsaturated fatty acids undergoing “on-pump” coronary artery bypass graft surgery. The length of hospital stay did not differ among all groups. Conclusions: N-3 polyunsaturated fatty acids administration significantly reduces the incidence of post-operative atrial fibrillation in patients undergoing “on-pump” coronary artery bypass graft surgery. N-3 polyunsaturated fatty acids therapy is not associated with a shorter hospital stay.

Instituto de Investigaciones Agropecuarias y Forestales. Facultad de Biología. Facultad de Medicina Veterinaria y Zootecnia. Facultad de Agrobiología. Facultad de Químico Farmacobiología. Programa Institucional de Maestría en Ciencias Biológicas Tomato is one of the most important crops in Mexico, in the state of Michoacan is the horticultural crop with the largest acreage and the highest production. However, the yield of tomato is affected by the disease late blight that could be devastating and able to cause 100% destruction on a producing area in a few days, if control measures are not implemented on time. The disease is caused by the oomycete Phytophthora infestans, an organism with high genetic variability in virulence, aggressiveness and sensivity to fungicides. Knowing the structure and dynamic of the pathogen population in a given geographic region could help us to implement appropriate practices for disease management. In order to study the populations of P. infestans, there are several markers both genotypic and phenotypic that provide extensive information about population characteristics in a given region. The studies of P. infestans have focused mainly on the populations of the central valley of Mexico on potato crops being the work done on populations that affect other regions of the country and on the tomato crop scarce. The aim of this study was to characterize populations of P. infestans attacking tomato in Michoacan in the field as well as in greenhouse, using different markers (mating type, metalaxyl sensitivity, isozyme genotype and mitochondrial haplotypes). Also it was determined whether the isolates were infective on potato and tomato and strains with opposite mating types obtained from these two hosts were crossed to test if reproductive compatibility existed between them. Isolates with both mating types were found in the field, as well as homothallic organisms. In the greenhouse only mating type A2 was detected. Most field isolates were sensitive to mefenoxam, while in the greenhouse the majority were tolerant. Three dilocus genotypes were detected for isozyme Glucose 6-phosphate isomerase and peptidase. El jitomate es uno de los cultivos de mayor importancia en el país, en Michoacán es la hortaliza con mayor superficie cultivada y la de mayor producción. Sin embargo, es afectado por el tizón tardío, una devastadora enfermedad capaz de ocasionar el 100% de destrucción de una zona productora en unos cuantos días, si las medidas de control no son implementadas a tiempo. La enfermedad es causada por el oomiceto Phytophtora infestans, organismo que presenta una alta variabilidad genética en lo que respecta a virulencia, agresividad y sensibilidad a fungicidas. Para que adecuadas prácticas de manejo de la enfermedad sean aplicadas, es necesario conocer la estructura y dinámica poblacional del patógeno. Existen una serie de marcadores tanto genotípicos como fenotípicos que proporcionan una amplia información sobre las características de la población o poblaciones existentes en una determinada región. Los trabajos sobre poblaciones de P. infestans se han enfocado principalmente a la parte central del valle de México y al cultivo de papa, siendo los estudios enfocados a otras regiones del país y al cultivo de jitomate muy escasos. El objetivo de este estudio fue llevar a cabo la caracterización de poblaciones de P. infestans atacando al jitomate en Michoacán, tanto en campo como en invernadero, utilizando diferentes marcadores (tipo de compatibilidad, sensibilidad al mefenoxam, genotipos isoenzimáticos y haplotipos mitocondriales). Además, se determinó si los aislamientos obtenidos eran infectivos en papa y jitomate. Asimismo, se realizaron pruebas de compatibilidad/incompatibilidad reproductiva realizando cruzas entre aislamientos con tipos de compatibilidad opuestos de estos dos hospederos. En campo se obtuvieron aislamientos con los dos TC, así como organismos homotálicos, mientras que en invernadero únicamente se obtuvo el TC A2. Los aislamientos obtenidos en campo fueron más sensibles al mefenoxam mientras que los de invernadero la mayoría fueron tolerantes. Se detectaron tres genotipos dilocus para los isoenzimas Glucosa 6-fosfato-isomerasa y Peptidasa.

Background:The optimum route for cardioplegia administration in patients with severe coronary disease is still under debate. This study compared clinical, echocardiographic, and biochemical results in patients with left main stem disease treated with 2 different strategies of myocardial protection.MethodsBetween March 2000 and November 2002, 148 consecutive patients with left main stem disease undergoing coronary artery bypass grafting were divided into 2 groups according to the route of cardioplegia delivery: antegrade in 87 patients (group A) or antegrade followed by retrograde in 61 patients (group B). Electrocardiography, troponin I, MB-creatine kinase, and MB-creatine kinase mass were performed at 12, 24, 48, and 72 hours postoperatively. Echocardiography was performed preoperatively and before hospital discharge. Data were stratified in subgroups of patients with the following associated risk factors: left ventricular hypertrophy, diabetes, and right coronary stenosis.ResultsGroups were homogeneous in preoperative and intraoperative variables, apart from the higher incidence of unstable angina and severity of left main stem disease in group B. Hospital deaths, intensive therapy unit and hospital stay, perioperative acute myocardial infarction, and intraaortic balloon pump support were similar in both groups. Postoperative recovery of left ventricle ejection fraction and wall motion score index did not differ between the 2 groups. However, postoperative atrial fibrillation was higher in group A (P = .015), especially in patients with diabetes (P < .0001). Troponin I was significantly higher in group A from postoperative hours 12 to 72 (P < .01), and the same pattern was observed in patients with diabetes (P < .001), critical right coronary stenosis (P < .001), and left ventricle hypertrophy (P < .001).ConclusionThe combined route of intermittent blood cardioplegia allows better results in left main stem disease. Such data are confirmed even in risk subgroups.

Objective: This retrospective chart review study aimed to evaluate whether a more aggressive staged approach can reduce morbility and mortality following post-cardiotomy deep sternal wound infection. Methods: Between 1979 and 2000, 14 620 patients underwent open heart surgery: mediastinitis developed in 124 patients (0.85%). Patients were divided in two groups: in 62 patients (Group A) (1979‐1994) an initial attempt of conservative antibiotic therapy was the rule followed by surgical approach in case of failure; in 62 patients (Group B) (1995‐2000) the treatment was staged in three phases: (1) wound debridment, removal of wires and sutures, closed irrigation for 10 days; (2) in case of failure open dressing with sugar and hyperbaric therapy (11 patients, 17%); (3) delayed healing and negative wound cultures mandated plastic reconstruction (three patients, 4%). Categorical values were compared using the Chi-square test, continuous data were compared by unpaired t-test. Results: Incidence of mediastinitis was higher in Group B (62 out of 5535; 1.3%) than in Group A (62 out of 9085; 0.7%) (Pa 0:007). Mean interval between diagnosis and treatment was shorter in Group B (18 ^ 6 days) than in group A (38 ^ 7 days) (Pa 0:001). Hospital mortality was higher in Group A (19/62; 31%) than in Group B (1 out of 62; 1.6%) (P , 0:001). Hospital stay was shorter in Group B (30.5 ^ 3 days) than in group A (44 ^ 9 days) (Pa 0:001). In Group B complete healing was observed in all the 61 survivors: 47 cases (76%) after Stage 1; 11 (18%) after Stage 2; three (4.8%) after Stage 3. Conclusions: Although partially biased by the fact that the two compared groups draw back to different decades, this study showed that an aggressive therapeutic protocol can significantly reduce morbility and mortality of deep sternal wound infection. q 2001 Elsevier Science B.V. All rights reserved.

A new model of surgical injury for the induction and development of stenosis in common rat carotids is described. This model differs from balloon angioplasty or vein graft systems currently applied on animals to develop stenosis, since it involves the entire vessel wall layers and mimics the injury occurring during arterial grafts, endarterectomy or organ transplantation. At different times following arterial damage, the pattern of expression of genes already known to be involved in the proliferation, differentiation, and apoptosis of smooth muscle cells (c-myc, Angiotensin II receptor 1, Bcl-2 and Bax α), as well as of Rb and Rb2 genes, whose pattern of expression after arterial injury has not yet been reported, was analyzed by semi-quantitative reverse transcription-polymerase chain reaction technique. Histological and histochemical analysis on carotid sections shows the morphological changes which occurred 30 days after surgical injury in the vessel wall. Molecular and histological data demonstrate that this model of surgical injury induces neointimal proliferation in about 30% of rats. In about 70% of the remaining rats, it induces the processes responsible for negative remodelling, namely the significant accumulation of extracellular matrix and fibers and disorganization of arterial tunics. This model is therefore available for further studies on the expression of genes involved in the arterial stenotic process, as well as for testing drugs aimed at limiting this recurrent pathophysiological phenomenon. J. Cell. Physiol. 186:307–313, 2001. © 2001 Wiley-Liss, Inc.

Background . To evaluate which variables predict recurrence of endocarditis after surgical treatment, we reviewed our 21-year experience. Methods . Between January 1979 and May 2000, 308 consecutive valve replacement procedures for infective endocarditis were performed in 271 patients. Univariate and multivariate time-related analyses were performed to retrospectively evaluate the role of the following variables in the development of recurrent postoperative endocarditis: gender, site of endocarditis, previous valve disease, drug abuse, diabetes, positive valve/blood cultures, sepsis, perivalvular involvement, previous embolic events, type of replacement device, and persistent postoperative fever. Results . Clinical and echocardiographic follow-up was 97.36% complete, mean follow-up time was 53.2 ± 3.4 months. Recurrent endocarditis developed in 58 cases (22.5%). Variables predicting recurrence were prosthetic endocarditis ( p = 0.00001), positive valve culture ( p = 0.0039), and persistence of fever at the seventh postoperative day ( p = 0.000001). Conclusions . Correct protocols of antibiotic therapy guided by microbiology may reduce the incidence of recurrent endocarditis to allow for surgery on sterile tissues and to prevent prosthetic infection. Recurrence rate is not affected by the choice of valve substitute, but can be prevented by complete surgical debridement.

Brucella endocarditis is a lifethreatening, often under-diagnosed complication of brucellosis. Seven cases of brucella endocarditis treated surgically in the last 25 years are described. The infection was localized on the aortic valve in 5 cases and on a prosthetic mitral valve in 2. All patients had a positive history of risk factors for brucella infection and all were in cardiac failure (5 in New York Heart Association functional class III and 2 in class IV). All underwent valve replacement followed by antibiotic therapy. Follow-up ranged from 1 and 206 months. One patient died following prosthetic valve replacement to treat a periprosthetic leak unrelated to the brucella infection. Brucella antibody tests and careful clinical history are mandatory in all patients with negative blood cultures in order to identify brucella earlier during the course of the infection before embolization or annular involvement occur.

The authors report their 18-year experience in the surgical treatment of infective tricuspid endocarditis. Between January 1981 and January 1999, 238 cases of infective endocarditis were seen. with a tricuspid involvement in 21 cases (8.8%). Tricuspid valve repair was performed in 9 patients with infective lesions involving one single leaflet. The surgical principle of the repair was to avoid any prosthetic material implantation. Posterior leaflet vegetectomy was performed in another 2 patients with infected intracavitary leads. Tricuspid valve replacement was performed in 10 patients with involvement of the whole valvular apparatus. One patient died of septic shock 3 days postoperatively. All the other patients had a good postoperative recovery. Follow-up ranged between 12 and 155 months (mean 68.9 +/- 55 months). Five cases of late mortality were observed: 3 for cardiac reasons and 2 of cancer. All the other patients are alive. Late postoperative echocardiography in the patients with tricuspid repair showed tricuspid regurgitation to be absent in 6 patients, mild in 2, moderate in 1, and severe in 1. No recurrent infections were observed either in patients with valve repair or in those with valve replacement. Good early and long-term results can be achieved in the surgical treatment of tricuspid endocarditis as long as complete excision of the infected tissue is performed and risk factors are controlled.

Objective We sought to compare the long-term clinical outcomes of patients who underwent isolated aortic valve replacement with single-disc and bileaflet mechanical heart valves. Methods From May 1975 through October 2001, 590 single-disc valves (7 models) were used for isolated valve replacement, and from November 1980 through July 2002, 1283 bileaflet valves (10 models) were used for isolated valve replacement. Detailed follow-up was performed to a maximum of 27.4 and 21.9 years with a total of 6872 and 5811 patient-years for single-disc valves and bileaflet valves, respectively. Survival and valve-related events were analyzed. Results Single-disc valves were mainly implanted from 1975 through 1995, whereas bileaflet valves were mainly implanted from 1987 through 2002; thus the years of concurrent use were 1987 through 1995. The bileaflet valve had a significantly lower explantation rate, whereas the single-disc valve had a significantly lower thromboembolism rate. No significant differences were detected in early mortality, long-term survival, and other valve-related complications. When limiting the comparison to the concurrent period of 1987 through 1995, no significant difference was detected in survival or in any valve-related complication. Conclusion Single-disc and bileaflet valves provide similar clinical performance. The predominant use of bileaflet valves is not based on clinical outcomes.