32 research outputs found

    Simulating rewetting events in intermittent rivers and ephemeral streams: A global analysis of leached nutrients and organic matter

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    Climate change and human pressures are changing the global distribution and the ex‐ tent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico‐chemical changes (precon‐ ditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experi‐ mentally simulated, under standard laboratory conditions, rewetting of leaves, river‐ bed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative character‐ istics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dis‐ solved substances during rewetting events (56%–98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contrib‐ uted most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached OM. The opposite pattern was found in the arid zone. Environmental vari‐ ables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached sub‐ stances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying event

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Granulomatous diseases of the breast and axilla: radiological findings with pathological correlation

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    Abstract Objectives This article reviews our experience and describes the literature findings of granulomatous diseases of the breast and axilla. Methods After approval of the Institutional Review Board was obtained, the surgical pathological records from January 2000 to January 2017 were searched for the keyword granulomatous. Clinical, imaging and histology findings were reviewed by both a fellowship-trained radiologist and a breast-imaging consultant radiologist, reviewing 127 patients (age range, 32–86 years; 126 women and 1 man). Results Most common causes of granulomatous lesions of the breast and axilla included silicone granulomas 33% (n = 42), fat necrosis 29% (n = 37) and suture granulomas 11% (n = 14). In 16% (n = 20), no cause could be found and clinical history was consistent with idiopathic granulomatous mastitis. Other granulomatous aetiologies included granulomatous infections, sarcoidosis and Sjögren’s syndrome. Causes of axillary granulomatous disease were similar to the breast; however, a case of cat-scratch disease was found that only involved the axillary lymph nodes. They can have a variable appearance on imaging and may mimic malignancy with irregular masses seen on mammography, ultrasound and magnetic resonance imaging. Fistulas to the skin and nipple retraction can suggest chronicity and a granulomatous aetiology. Combination of clinical history, laboratory and imaging findings can be diagnostic. Conclusions Granulomatous processes of the breast are rare. The diagnosis can, however, be made if there is relevant history (prior trauma, silicone breast implants, lactation), laboratory (systemic or infectious processes) and imaging findings (fistula, nipple retraction). Recognising these entities is important for establishing pathological concordance after biopsy and for preventing unnecessary treatment. Teaching points Breast granulomatous are rare but can mimic breast carcinoma on imaging Imaging with clinical and laboratory findings can correctly diagnosis specific granulomatous breast diseases Recognition of the imaging findings allows appropriate pathological concordance and treatmen

    Paracoccidioidomicose aguda/subaguda disseminada. Primeiro caso no Rio Grande do Sul Acute/subacute disseminated paracoccidioidomycosis. First case in Rio Grande do Sul State, Brazil

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    É relatado o primeiro caso autóctone de paracoccidioidomicose disseminada aguda/subaguda ocorrido em criança no Rio Grande do Sul. A doença iniciou com adenomegalias superficiais generalizadas, seis meses antes da internação hospitalar. O diagnóstico foi feito através de biópsia de gânglio cervical. É comentado o espectro de formas clínicas da micose observado nesse Estado.<br>The first autochthonous case of acute/subacute disseminated paracoccidioidomycosis observed in a child in Rio Grande do Sul (Brazil) is reported. The disease started with widespread superficial lymphadenopathy six months before the patient was admitted to the hospital. The diagnosis was made through a cervical lymph node biopsy. The spectrum of the clinical forms of the mycosis observed in this State is commented upon

    Development, survival and reproduction of Podisus nigrispinus (Dallas, 1851) (Heteroptera: Pentatomidae) with salt and amino acids solutions supplementary diet

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    This study presents the effect of a supplementary diet with amino acids and sodium chloride solutions in addition to prey on the development, survival and reproduction of the predator Podisus nigrispinus (Heteroptera, Pentatomidae). Both solutions showed deleterious effects on nymph survival, adult weight, female longevity, number of egg masses, eggs per female, eggs per egg mass and nymphs per female besides egg viability of P. nigrispinus when compared with diet with water and prey. When compared with plant supplements in the diet the use of amino acids and salt solutions for mass rearing of P. nigrispinus was inferior.<br>O presente estudo mostra o efeito da suplementação alimentar com soluções de aminoácidos e salina (NaCl) no desenvolvimento, sobrevivência e reprodução de Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae). Ambas soluções causaram efeito deletério na sobrevivência ninfal, peso dos adultos, longevidade das fêmeas e nos números de posturas, de ovos/fêmea, de ovos/postura e de ninfas, bem como na viabilidade dos ovos de P. nigrispinus quando comparado com estes insetos que além de presa receberam água. Estes resultados são discutidos em comparação com o efeito positivo que a suplementação alimentar com plantas tem sido relatada para esses predadores e sugerem que o uso de plantas é melhor que a substituição por solução de aminoácidos em sistemas de criação em laboratório desses predadores
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