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Worldwide coffee production is threatened by climate change, which highlights the importance of heat tolerance studies. Here we tested the hypothesis that photosynthetic heat tolerance in coffee varieties changes according to acclimation to distinct light conditions. Furthermore, we tested if heat tolerance is associated with the habitat of origin of the coffee species. We evaluated heat tolerance using chlorophyll fluorescence in varieties of Coffea arabica (Mundo Novo and Catuai Amarelo) and C. canephora (Conilon) grown in a common garden under two conditions: high (HS) and low (LS) sunlight. Leaf traits associated with leaf cooling were evaluated in plants grown in LS and HS and associations of heat tolerance with these traits were determined. The varieties tested had high photosynthetic heat tolerance, with temperatures above 54 °C leading to a 50% reduction in Fv /Fm (T50 ). The heat tolerance of each Coffea variety was unaffected by growth in distinct light conditions. Leaves of plants grown in LS were larger and had a lower fraction of the leaf area occupied by stomata (nast ). Heat tolerance was positively associated with leaf size and negatively with nast . C. canephora exhibited higher heat tolerance than C. arabica. The limited plasticity of heat tolerance in response to acclimation under distinct light conditions contradicts the prediction that plants acclimated to HS would have higher photosynthetic heat tolerance than those acclimated to LS. Our results on heat tolerance among Coffea species/varieties in HS and LS indicate the possibility of selection of varieties for better acclimation to ongoing climate changes.

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In this work, we present a temperature-dependent behavior of monoclinic silver dimolybdate (m-Ag2Mo2O7) microrods using in situ Raman scattering. The m-Ag2Mo2O7 microrods were obtained by the conventional hydrothermal method at 423 K for 24 h. The structural and morphological characterization of the sample has been done by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Temperature-dependent Raman scattering measurements were performed on m-Ag2Mo2O7 microrods, and the results show an irreversible first-order structural phase transition at 698 K-723 K and the melting process at 773 K. Changes in the Raman spectra confirm the phase transition from the P21/c monoclinic structure to the P-1 triclinic structure. No morphological changes were observed during the structural phase transition of the sample at 723 K. Time-dependent optical microscopy at 773 K showed the growth of nanowires on the Ag2Mo2O7 microrods in the triclinic structure.

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The present study aims to compare the effectiveness of surgical and medical therapy in reducing the risk of cancer in Barrett's esophagus in a long-term evaluation. A prospective cohort was designed that compared Barrett's esophagus patients submitted to medical treatment with omeprazole or laparoscopic Nissen fundoplication. The groups were compared using propensity score matching paired by Barrett's esophagus length. A total of 398 patients met inclusion criteria. There were 207 patients in the omeprazole group (Group A) and 191 in the total fundoplication group (Group B). After applying the propensity score matching paired by Barrett's esophagus length, the groups were 180 (Group A) and 190 (Group B). Median follow-up was 80 months. Group B was significantly superior for controlling GERD symptoms. Group B was more efficient than Group A in promoting Barrett's esophagus regression or blocking its progression. Group B was more efficient than Group A in preventing the development of dysplasia and cancer. Logistic regression was performed for the outcomes of adenocarcinoma and dysplasia. Age and body mass index were used as covariates in the logistic regression models. Even after regression analysis, Group B was still superior to Group A to prevent esophageal adenocarcinoma or dysplasia transformation (odds ratio [OR]: 0.51; 95% confidence interval [CI]: 0.27-0.97, for adenocarcinoma or any dysplasia; and OR: 0.26; 95% CI: 0.08-0.81, for adenocarcinoma or high-grade dysplasia). Surgical treatment is superior to medical management, allowing for better symptom control, less need for reflux medication use, higher regression rate of the columnar epithelium and intestinal metaplasia, and lower risk for progression to dysplasia and cancer.

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The concentrations of As, Cd, Cu, Pb and Zn were measured in muscle tissue of Coryphaena hippurus captured in the southern Gulf of California to determine inter-annual variations and their relation with environmental parameters for the period 2006-2015; additionally, health risk to consumers was assessed according to levels of studied elements and rate of fish consumption in northwest Mexico. During 2014 and 2015 the levels of As, Cd, Cu, and Zn were significantly lower than the rest of the years; in the case of As, it was also significantly lower in 2010. Oceanic Niño Index was negatively correlated with Zn concentrations in fish, while sea surface temperature was negatively correlated with Zn, Pb and Cd concentrations in dolphinfish. The simultaneous occurrence of the analyzed elements in muscle of dolphinfish indicated that health effects on consumers are not likely to occur; nevertheless, fishermen with elevated fish consumption might be at risk.

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O gelo é fundamental para a conservação adequada do pescado, pois retarda o crescimento microbiano, preservando a qualidade físico-química, microbiológicas e características organolépticas. No entanto, o gelo pode ser fonte de risco para a saúde dos consumidores quando produzido sob más condições sanitárias. Pontos críticos devem ser controlados durante a etapa de produção e armazenagem do gelo, como, uso de água potável e condições higiênicas-sanitárias. A presença de altas populações de microrganismos heterotróficos e coliformes e a má qualidade físico-química do gelo utilizado para conservação de pescado pode representar um risco potencial ao consumidor, podendo ser veiculador de doenças como Salmonelose, infecção por Escherichia coli e intoxicação por Staphylococcus aureus, além de reduzir a vida útil de prateleira do produto. Neste contexto, a realização deste estudo teve como objetivo avaliar a qualidade microbiológica e físico-química do gelo utilizado na conservação de pescados comercializados em Rio Branco - AC. Foram analisadas 15 amostras de gelo coletadas em três diferentes supermercados. Foi preconizado a coleta de gelo fabricado com maquinário próprio e que fossem utilizados na comercialização do pescado fresco, que seriam expostos e resfriados em bancas de gelo no local. Foram colhidas 300g de gelo manualmente com uso de luvas e acondicionadas em frascos de vidros esterilizados, em caixa isotérmica. A qualidade microbiológica destas amostras foi analisada pela contagem de microrganismos heterotróficos mesófilos e psicrotróficos. Além disso, foi realizada a determinação do número mais provável de coliformes totais á 30°C, termotolerantes e a quantificação do pH e cloro residual livre das amostras. Com relação a determinação de microrganismos mesófilos, foram registrados valores entre 1,0x10¹ e 9,15x103 UFC/mL com amostras fora do padrão estabelecido pela Portaria MG/MS n°888/2021. A quantidade de psicrotróficos variou entre 1,0x10¹ e 89,8x10³ UFC/mL. Foi registrada a presença de coliformes totais á 30°C em 6 amostra e de termotolerantes em 4 amostras. Portanto, foi registrado variação nos padrões de qualidade dos gelos fabricados nos supermercados para conservação do pescado, constituindo risco potencial para a saúde dos consumidores.

The ice is essential for the proper conservation of fish, as it delays microbial growth, preserving the physical-chemical, microbiological and organoleptic characteristics. However, ice can be a source of health risk for consumers when produced under poor sanitary conditions. Critical points must be controlled during the ice production and storage stage, such as the of potable water and hygienic-sanitary conditions. The presence of high populations of heterotrophic and coliform microorganisms and the poor physicochemical quality of the ice used for fish conservation can represent a potential risk to the consumer, which can be a carrier of diseases such as Salmonellosis, Escherichia coli infection and Staphylococcus aureus poisoning, in addition to reducing the shelf life of the product. In this context, this study aimed to evaluate the microbiological and physical-chemical quality of the ice used in the conservation of fish marketed in Rio Branco - AC. 15 ice samples collected in three different supermarkets were analyzed. It was recommended the collection of ice manufactured with its own machinery and that it be used in the commercialization of fresh fish, which would be exposed and cooled in ice stalls on site 300g ice manually with the use of gloves and packed in sterilized glass bottles, in an isothermal box. The microbiological quality of these samples was analyzed by counting mesophilic and psychrotrophic heterotrophic microorganisms. In addition, the determination of the most probable number of total coliforms at 30°C, thermotolerant and the quantification of pH and free residual chlorine of the samples were performed. Regarding the determination of mesophilic microorganisms, values between 1,00x10¹ and 9,15x10³ UFC/mL were recorded with samples (60%) out of the standard established by Ordinance MG/MS No. 888/2021. The amount of psychrotrophs varied between 1,00x10¹ and 8,98x103 CFU/mL. The presence of total coliforms at 30°C was recorded in 6 samples and of thermotolerants in 4 samples. Therefore, there was a variation in the quality standards of ices manufactured in supermarkets for fish conservation, constituting a potential risk to the health of consumers.

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This study investigated the acute blockade of endogenous melatonin (MLT) using Luzindole with or without systemic lipopolysaccharide (LPS) challenge and evaluated changes in inflammatory and oxidative stress markers in the mouse jejunum. Luzindole is an MT1/MT2 MLT receptor antagonist. Both receptors occur in the small intestine. Swiss mice were treated with either saline (0.35 mg/kg, ip), Luzindole (0.35 mg/kg, ip), LPS (1.25 mg/kg, ip), or Luzindole+LPS (0.35 and 1.25 mg/kg, ip, respectively). Jejunum samples were evaluated regarding intestinal morphometry, histopathological crypt scoring, and PAS-positive villus goblet cell counting. Inflammatory Iba-1, interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, nuclear factor (NF)-kB, myeloperoxidase (MPO), and oxidative stress (NP-SHs, catalase, MDA, nitrate/nitrite) markers were assessed. Mice treated with Luzindole, LPS, and Luzindole+LPS showed villus height shortening. Crypt damage was worse in the LPS group. Luzindole, LPS, and Luzindole+LPS reduced the PAS-goblet cell labeling and increased Iba-1-immunolabelled cells compared to the saline group. Immunoblotting for IL-1ß, TNF-α, and NF-kB was greater in the Luzindole group. The LPS-challenged group showed higher MPO activity than the saline and Luzindole groups. Catalase was reduced in the Luzindole and Luzindole+LPS groups compared to saline. The Luzindole group showed an increase in NP-SHs, an effect related to compensatory GSH activity. The acute blockade of endogenous MLT with Luzindole induced early changes in inflammatory markers with altered intestinal morphology. The other non-detectable deleterious effects of Luzindole may be balanced by the unopposed direct action of MLT in immune cells bypassing the MT1/MT2 receptors.

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This study verified the effects of respiratory muscle training (RMT) on hemodynamics, heart rate (HR) variability, and muscle morphology in rats with streptozotocin-induced diabetes mellitus (DM). Thirty-six male Wistar rats were randomized into 4 groups and 34 completed the study: i) sham-sedentary (Sham-ST; n=9); ii) sham-RMT (Sham-RMT; n=9); iii) DM-sedentary (DM-ST; n=8); and iv) DM-RMT (DM-RMT; n=8). Hemodynamics were assessed by central cannulation, and R-R intervals were measured by electrocardiogram. In addition, the effects of RMT on the cross-sectional area of the diaphragm, anterior tibial, and soleus muscles were analyzed. The induction of DM by streptozotocin resulted in weight loss, hyperglycemia, reduced blood pressure, and attenuated left ventricular contraction and relaxation (P<0.05). We also observed a decrease in root mean square of successive differences between adjacent RR intervals (RMSSD) index and in the cross-sectional area of the muscles assessed, specifically the diaphragm, soleus, and anterior tibial muscles in diabetic rats (P<0.05). Interestingly, RMT led to an increase in RMSSD in rats with DM (P<0.05). The induction of DM produced profound deleterious changes in the diaphragmatic and peripheral muscles, as well as impairments in cardiovascular hemodynamics and autonomic control. Nevertheless, RMT may beneficially attenuate autonomic changes and improve parasympathetic modulation.

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Abstract We report the first known occurrence of Panstrongylus megistus (Burmeister, 1835) (Hemiptera, Reduviidae, Triatominae) in the Metropolitan Region of São Paulo, Brazil. In 2018, adult specimens were sent by residents to the competent authorities and, in the inspection of the property, a large focus associated with a marsupial nest was found. This finding reinforces the importance of the species in the state of São Paulo, serves as an alert for epidemiological surveillance and extends the species colonization area in the state of São Paulo.

Resumo Relatamos a primeira ocorrência de Panstrongylus megistus (Burmeister, 1835) (Hemiptera, Reduviidae, Triatominae) na Região Metropolitana de São Paulo, Brasil. Em 2018, espécimes adultos foram enviados por residentes e a pesquisa na propriedade constatou a presença de um grande foco associado a um ninho marsupial. Este achado reforça a importância da espécie no estado de São Paulo, serve de alerta para a vigilância epidemiológica e amplia a área de colonização da espécie no estado de São Paulo.

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