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INTRODUÇÃO: Em pacientes que foram submetidos a ablação por cateter devido a fibrilação atrial pode ocorrer a recorrência deste quadro. Não é estabelecido o efeito do S/V na prevenção da recorrência de fibrilação atrial (FA) comparado a Inibidores da Enzima Conversora da Angiotensina (IECA) ou Bloqueadores do Receptor da Angiotensina II (BRA). Essa metaanálise visa estabelecer qual a melhor escolha terapêutica para prevenção da recorrência de FA após ablação por catéter. MÉTODO: Foi realizada uma busca sistemática nas bases do PubMed, Embase e Cochrane para ensaios clínicos randomizados (ECR) e estudos observacionais comparando uso de S/V com IECA/BRA em pacientes que realizaram ablação por cateter. Os resultados foram apresentados em diferenças de médias (DM), com intervalo de confiança de 95% (IC). A heterogeneidade foi avaliada pelo I2 e desfechos expressos em riscos relativos (RR), utilizando o software R versão 4.2.3. RESULTADOS: Foram incluídos 3 ensaios clínicos randomizados e 1 estudo de coorte, composto por 642 pacientes, com 319 pacientes no grupo S/V e 323 no grupo controle. O seguimento dos estudos variou de 12 meses a 36 meses, a média de idade variou de 58.9 a 65.82 anos. Foi demonstrado a redução de ocorrência de FA persistente com uma diferença significativa favorecendo o grupo S/V (RR 0.43; 95% IC 0,25-0.76; P=0.003; I2=80%) comparado com o grupo IECA/BRA. Na análise houve uma redução significativa do Índice de Volume Atrial Esquerdo (IVAE) (MD -5.34ml/m2; 95% IC -8.77,-1.91; P=0.002; I2= 57%) no grupo S/V comparado com IECA/BRA. Não houve diferença significativa da fração de ejeção do ventrículo esquerdo com o uso de S/V (MD 1.24%; 95% IC -0.13, 2.61; P=0.076; I2= 0%) em comparação com IECA/BRA. CONCLUSÃO: Nesta metanálise, foi evidenciada a eficácia de S/V na diminuição da incidência de FA em pacientes submetidos à ablação por cateter, em comparação ao uso de IECA/ BRA. Contudo, ressalta-se a necessidade de realização de mais ensaios clínicos randomizados para uma avaliação mais abrangente de sua eficácia na redução da recorrência de FA em paciente pós ablação por cateter na prática clínica.

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INTRODUÇÃO: Diversos estudos foram publicados avaliando o uso da denervação renal por radiofrequência (DRR) no tratamento de pacientes com hipertensão arterial resistente (HAR). Essa técnica consiste em um procedimento minimamente invasivo que visa interromper a atividade dos nervosrenais via ablação. Entretanto,sua eficácia e segurança com cateter via radiofrequência ainda não foi elucidada. Essa meta-análise tem por objetivo investigar a eficácia da denervação renal por radiofrequência (DRR) comparado com sham ou anti hipertensivos. METODOLOGIA: Foi realizada uma busca nas bases de dados da PubMed, Embase e Cochrane, por ensaios clínicos randomizados que compararam a redução da pressão arterial entre a denervação renal por radiofrequência (DRR) e o sham ou tratamento padrão em pacientes com HAR. Os dados foram reunidos usando um modelo de efeito fixo, e os resultados foram dados em diferença de média (DM) e risco relativo (RR), com 95% de intervalo de confiança (IC). A heterogeneidade entre os estudos foi calculada pelo I2. Todas as estatísticas foram realizadas usando o R software(version 4.0.3). RESULTADOS: Ao todo foram incluídos 8 ensaios clínicos randomizados, composto por 934 pacientes (557 do grupo RDN e 377 do grupo controle). O seguimento dos estudos variou de 6 meses até 84 meses, a média de idade variou entre 53 a 64.5 anos e com 349 pacientes portadores de diabetes tipo 2. A DRR foi associada com redução significativa da pressão sistólica ambulatorial (DM: -6.25 mmHg, 95% IC: -8.83; -3.67, P< 0.001, I2= 52%), assim como na diastólica ambulatorial (DM: -2.67 mmHg, 95% IC: -4.38; -0.95, P=0.002, I2=50%) comparado com grupo controle. De maneira semelhante, houve redução significativa da pressão diastólica de consultório (DM: -5.11 mmHg, 95% IC: -9.19; -1.02, P=0.014, I2=72%). Não houve diferença estatística em relação à pressão sistólica de consultório (DM: -9.50 mmHg, 95% IC:-20.54; 1.54, P=0.092, I2=87%), aos efeitos adversos secundários (RR: 1.86, 95% IC: 0.66; 5.26, P=0.240, I2= 50%) e à crise hipertensiva (RR:1.10, 95% IC: 0.55; 2.22, P=0.780, I2=0%). CONCLUSÕES: Esta meta-análise demonstrou a eficácia do uso da DRR na redução da pressão arterial global ambulatorial e pressão diastólica de consultório, e não apresentou aumentos de efeitos adversos secundários e crise hipertensiva. Esses achados demonstram o potencial uso da DRR no tratamento de pacientes que possuem hipertensão arterial resistente.

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INTRODUCTION AND AIMS: An anastomotic leak is one of the most dreaded complications in colorectal surgery because it increases postoperative morbidity and mortality. The aim of the present study was to identify whether indocyanine green fluorescence angiography (ICGFA) reduced the anastomotic dehiscence rate in colorectal surgery. MATERIAL AND METHODS: A retrospective study on patients that underwent colorectal surgery with colonic resection or low anterior resection and primary anastomosis, within the time frame of January 2019 and September 2021, was conducted. The patients were divided into the case group, in which ICGFA was performed for the intraoperative evaluation of blood perfusion at the anastomosis site, and the control group, in which ICGFA was not utilized. RESULTS: A total of 168 medical records were reviewed, resulting in 83 cases and 85 controls. Inadequate perfusion that required changing the surgical site of the anastomosis was identified in 4.8% of the case group (n = 4). A trend toward reducing the leak rate with ICGFA was identified (6% [n = 5] in the cases vs 7.1% in the controls [n = 6] [p = 0.999]). The patients that underwent anastomosis site change due to inadequate perfusion had a 0% leak rate. CONCLUSIONS: ICGFA as a method to evaluate intraoperative blood perfusion showed a trend toward reducing the incidence of anastomotic leak in colorectal surgery.

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INTRODUCTION AND AIM: Anastomosis leak occurs in 1-19% of colorrectal surgeries. Our objective was to present the first Mexican case series on colorrectal surgery using indocyanine green fluorescence angiography to evaluate perfusion prior to carrying out the anastomosis. MATERIALS AND METHODS: A retrospective, analytic, descriptive study was conducted. We studied the case records of consecutive patients that underwent colorrectal surgery with indocyanine green angiography performed by the same group of colorrectal surgeons. RESULTS: Twenty-one case records were reviewed. Eleven (52.3%) of the patients were women, mean patient age was 57 years (38-82), and mean body mass index was 25 kg/m2 (17-34). Fifteen (71.4%) patients were diagnosed with malignant disease. Indocyanine green angiography changed our therapeutic decision in three (14.2%) patients. Two colorrectal anastomoses (14.2%) were performed at fewer than 5 cm from the anal verge and 13 (61.9%) were performed at more than 5 cm from the anal verge. Three of the anastomoses were ileocolic (14.2%), two were coloanal (9.5%), and one was ileoanal (4.7%). There were six (28.5%) complications, no cases of anastomotic leak, and no complications associated with the use of indocyanine green. The mortality rate was 0%. CONCLUSION: The present case series is the first on colorrectal surgery conducted in Mexico using indocyanine green fluorescence angiography, with excellent results.

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Hybrid diamond-like carbon (DLC) with incorporated titanium dioxide (TiO2) nanoparticle coatings have low friction coefficient, high wear resistance, high hardness, biocompatibility, and high chemical stability. They could be employed to modify biomedical alloys surfaces for numerous applications in biomedical engineering. Here we investigate for the first time the in vivo inflammatory process of DLC coatings with incorporated TiO2 nanoparticles. TiO2-DLC films were grown on AISI 316 stainless-steel substrates using plasma-enhanced chemical vapor deposition. The coated substrates were implanted in CF1 mice peritoneum. The in vivo cytotoxicity and biocompatibility of the samples were analyzed from macrophage lavage. Analysis in the first weeks after implantation could be helpful to evaluate the acute cytotoxicity generated after a possible inflammatory process. The in vivo results showed no inflammatory process. A significant increase in nitric oxide production on the uncoated substrates was confirmed through cytometry, and the coated substrates demonstrated biocompatibility. The presence of TiO2 nanoparticles enhanced the wound healing activity, due to their astringent and antimicrobial properties. DLC and TiO2-DLC coatings were considered biocompatible, and the presence of TiO2 nanoparticles reduced the inflammatory reactions, increasing DLC biocompatibility.

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INTRODUCTION AND AIM: Anastomotic leak occurs in 1-19% of colorrectal surgeries. Our objective was to present the first Mexican case series on colorrectal surgery using indocyanine green fluorescence angiography to evaluate perfusion prior to carrying out the anastomosis. MATERIALS AND METHODS: A retrospective, analytic, descriptive study was conducted. We studied the case records of consecutive patients that underwent colorrectal surgery with indocyanine green angiography performed by the same group of colorrectal surgeons. RESULTS: Twenty-one case records were reviewed. Eleven (52.3%) of the patients were women, mean patient age was 57 years (38-82), and mean body mass index was 25 kg/m2 (17-34). Fifteen (71.4%) patients were diagnosed with malignant disease. Indocyanine green angiography changed our therapeutic decision in three (14.2%) patients. Two colorrectal anastomoses (14.2%) were performed at fewer than 5 cm from the anal verge and 13 (61.9%) were performed at more than 5 cm from the anal verge. Three of the anastomoses were ileocolic (14.2%), two were coloanal (9.5%), and one was ileoanal (4.7%). There were six (28.5%) complications, no cases of anastomotic leak, and no complications associated with the use of indocyanine green. The mortality rate was 0%. CONCLUSION: The present case series is the first on colorrectal surgery conducted in Mexico using indocyanine green fluorescence angiography, with excellent results.

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Mechanisms involving ammonium toxicity, excess light, and photosynthesis are scarcely known in plants. We tested the hypothesis that high NH4+ supply in presence of high light decreases photosynthetic efficiency of rice plants, an allegedly tolerant species. Mature rice plants were previously supplied with 10 mM NH4+ or 10 mM NO3- and subsequently exposed to 400 µmol m-2 s-1 (moderate light-ML) or 2000 µmol m-2 s-1 (high light-HL) for 8 h. HL greatly stimulated NH4+ accumulation in roots and in a minor extent in leaves. These plants displayed significant delay in D1 protein recovery in the dark, compared to nitrate-supplied plants. These responses were related to reduction of both PSII and PSI quantum efficiencies and induction of non-photochemical quenching. These changes were also associated with higher limitation in the donor side and lower restriction in the acceptor side of PSI. This later response was closely related to prominent decrease in stomatal conductance and net CO2 assimilation that could have strongly affected the energy balance in chloroplast, favoring ATP accumulation and NPQ induction. In parallel, NH4+ induced a strong increase in the electron flux to photorespiration and, inversely, it decreased the flux to Rubisco carboxylation. Overall, ammonium supply negatively interacts with excess light, possibly by enhancing ammonium transport towards leaves, causing negative effects on some photosynthetic steps. We propose that high ammonium supply to rice combined with excess light is capable to induce strong delay in D1 protein turnover and restriction in stomatal conductance, which might have contributed to generalized disturbances on photosynthetic efficiency.

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Recently, the development of coatings to protect biomedical alloys from oxidation, passivation and to reduce the ability for a bacterial biofilm to form after implantation has emerged. Diamond-like carbon films are commonly used for implanted medical due to their physical and chemical characteristics, showing good interactions with the biological environment. However, these properties can be significantly improved when titanium dioxide nanoparticles are included, especially to enhance the bactericidal properties of the films. So far, the deposition of hydroxyapatite on the film surface has been studied in order to improve biocompatibility and bioactive behavior. Herein, we developed a new route to obtain a homogeneous and crystalline apatite coating on diamond-like carbon films grown on 304 biomedical stainless steel and evaluated its antibacterial effect. For this purpose, films containing two different concentrations of titanium dioxide (0.1 and 0.3g/L) were obtained by chemical vapor deposition. To obtain the apatite layer, the samples were soaked in simulated body fluid solution for up to 21days. The antibacterial activity of the films was evaluated by bacterial eradication tests using Staphylococcus aureus biofilm. Scanning electron microscopy, X-ray diffraction, Raman scattering spectroscopy, and goniometry showed that homogeneous, crystalline, and hydrophilic apatite films were formed independently of the titanium dioxide concentration. Interestingly, the diamond-like films containing titanium dioxide and hydroxyapatite reduced the biofilm formation compared to controls. A synergism between hydroxyapatite and titanium dioxide that provided an antimicrobial effect against opportunistic pathogens was clearly observed.

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Graphene oxide nanoribbons (O-GNR) surges as an interesting nanomaterial for biomedical applications due to feasibility to incorporate functional groups and possible bactericidal properties. Herein, high concentrations of O-GNR were biologically evaluated using human osteoblast cells and gram positive and negative bacteria. Briefly, our goal were to evaluate: (1) synthetic pathway, (2) characterization and (3) effects of O-GNR composition and structural factors as a new approach for biomedical applications. For this, O-GNR were produced combining chemical vapor deposition and oxygen plasma treatment of multiwalled carbon nanotubes. Then, we analyzed the bioactivity, cell viability, osteogenic differentiation, matrix mineralization, mRNA levels of the five genes related direct to bone repair and bactericidal effect of high concentrations of O-GNR (10µgmL-1, 100µgmL-1, 200µgmL-1 and 300µgmL-1). Impressively, O-GNR showed no cytotoxic effects up to a concentration of 100µgmL-1 and no gene expression alteration when used in its dose. We also observed that S. aureus and E. coli bacteria are susceptible to damage when incubated with 100µgmL-1 of O-GNR, showing approximately 50% of bacterial death. We consider that O-GNR displays attractive properties when used at a suitable dose, displaying bactericidal effect and apparently lacking to cause damages in the bone repair process.

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The central abundance hypothesis predicts that local adaptation is a function of the distance to the centre of a species' geographic range. To test this hypothesis, we gathered genomic diversity data from 49 populations, 646 individuals and 33,464 SNPs of two wild relatives of maize, the teosintes Zea mays ssp. parviglumis and Zea. mays. ssp. mexicana. We examined the association between the distance to their climatic and geographic centroids and the enrichment of SNPs bearing signals of adaptation. We identified candidate adaptive SNPs in each population by combining neutrality tests and cline analyses. By applying linear regression models, we found that the number of candidate SNPs is positively associated with niche suitability, while genetic diversity is reduced at the limits of the geographic distribution. Our results suggest that overall, populations located at the limit of the species' niches are adapting locally. We argue that local adaptation to this limit could initiate ecological speciation processes and facilitate adaptation to global change.

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