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1.
An Acad Bras Cienc ; 94(suppl 1): e20210625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35170671

RESUMO

Sulfurization is a pedogenic process that involves pyrite oxidation and strong soil acidification, accounting for the formation of acid sulfate soils. In Antarctica, acid sulfate soils are related to specific parent materials, such as sulfide-bearing andesites in Maritime Antarctica and pyritized sedimentary rocks in James Ross Archipelago. The hypothesis is that the acid sulfate soils of these regions vary according with a climate gradient. The reviewing of current data showed that the acid sulfate soils of warmer and wetter Maritime Antarctica have a greater weathering degree, higher acidity, leaching, phosphorus adsorption capacity, structural development, and well-crystallized iron oxides and kaolinite formation. On the other hand, the sulfurization at the drier region of James Ross Archipelago is counterbalanced by the semiaridity, resulting in lower acidity and higher base contents combined with little morphological and mineralogical evolution besides presence of weatherable minerals in the clay fraction. The sulfurization process interplays with other pedogenic processes, such as the phosphatization in Maritime Antarctica and salinization in James Ross Archipelago. Higher temperatures and soil moisture enhance the pedogenesis, showing that even the Antarctic sulfate soils, which originated from specific parent materials, have their development and characteristics controlled by a clear climatic gradient.


Assuntos
Poluentes do Solo , Solo , Regiões Antárticas , Minerais , Poluentes do Solo/análise , Sulfatos
2.
J Clin Endocrinol Metab ; 107(1): e394­e400, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324679

RESUMO

CONTEXT: Coronavirus disease 2019 (COVID-19) is a proinflammatory and prothrombotic condition, but its impact on adrenal function has not been adequately evaluated. CASE REPORT: A 46-year-old woman presented with abdominal pain, hypotension, skin hyperpigmentation after COVID-19 infection. The patient had hyponatremia, serum cortisol <1.0 ug/dL, ACTH of 807 pg/mL and aldosterone <3 ng/dL. Computed tomography (CT) findings of adrenal enlargement with no parenchymal and minimal peripheral capsular enhancement after contrast were consistent with bilateral adrenal infarction. The patient had autoimmune hepatitis and positive antiphospholipid antibodies, but no previous thrombotic events. The patient was treated with intravenous hydrocortisone, followed by oral hydrocortisone and fludrocortisone. DISCUSSION: Among 115 articles, we identified nine articles, including case reports, of new-onset adrenal insufficiency and/or adrenal hemorrhage/infarction on CT in COVID-19. Adrenal insufficiency was hormonally diagnosed in five cases, but ACTH levels were measured in only three cases (high in one case and normal/low in other two cases). Bilateral adrenal non- or hemorrhagic infarction was identified in five reports (two had adrenal insufficiency, two had normal cortisol levels and one case had no data). Interestingly, the only case with well-characterized new-onset acute primary adrenal insufficiency after COVID-19 had a previous diagnosis of antiphospholipid syndrome. In our case, antiphospholipid syndrome diagnosis was established only after the adrenal infarction triggered by COVID-19. CONCLUSIONS: Our findings support the association between bilateral adrenal infarction and antiphospholipid syndrome triggered by COVID-19. Therefore, patients with positive antiphospholipid antibodies should be closely monitored for symptoms or signs of acute adrenal insufficiency during COVID-19.

3.
Antioxidants (Basel) ; 9(10)2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33049969

RESUMO

The cardioprotective effects of dietary nitrate from beetroot in healthy and hypertensive individuals are undeniable and irrefutable. Nitrate and nitrate-derived nitrite are precursors for nitric oxide synthesis exhibiting an effect on cardiomyocytes and myocardial ischemia/reperfusion, improving endothelial function, reducing arterial stiffness and stimulating smooth muscle relaxation, decreasing systolic and diastolic blood pressures. Beetroot phytochemicals like betanin, saponins, polyphenols, and organic acids can resist simulated gastrointestinal digestion, raising the hypothesis that the cardioprotective effects of beetroots result from the combination of nitrate/nitrite and bioactive compounds that limit the generation of reactive oxygen species and modulate gene expression. Nitrate and phytochemical concentrations can be adjusted in beet formulations to fulfill requirements for acute or long-term supplementations, enhancing patient adherence to beet intervention. Based on in vitro, in vivo, and clinical trials, beet nitrate and its bioactive phytochemicals are promising as a novel supportive therapy to ameliorate cardiovascular diseases.

4.
Obes Surg ; 30(12): 4840-4851, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32700180

RESUMO

PURPOSE: Growing evidence in the literature suggests that obesity is capable of altering reproductive hormone levels and male fertility. Effects on classic semen parameters and sperm DNA fragmentation (SDF), however, have not been properly established. Additionally, the impact of bariatric surgery (BS) on those parameters is still controversial. MATERIALS AND METHODS: In Phase 1, 42 patients with obesity and 32 fertile controls were submitted to reproductive hormone evaluation, semen analysis, and SDF testing. In Phase 2, patients with obesity were submitted to BS or clinical follow-up and were invited to 6-month revaluation. RESULTS: Phase 1: Men with obesity have higher levels of estradiol, LH, and FSH and lower levels of total testosterone (TT) when compared with eutrophic fertile men. Additionally, they present worse semen parameters, with reduction in ejaculated volume and sperm concentration, worse sperm motility and morphology, and higher SDF. Phase 2: 32 patients returned to revaluation. Eighteen were submitted to BS (group S) and 14 were not submitted to any specific therapeutic regimen (group NS). In group S, TT more than doubled after surgery (294.5 to 604 ng/dL, p < 0.0001). Worsening of sperm concentration and total ejaculated sperm count were also noticed, and 2 patients became azoospermic after BS. SDF, however, improved after the procedure. No changes in the variables studied were observed in non-operated patients. CONCLUSION: In this prospective study, we have found that BS results in improvements in reproductive hormone levels and SDF after 6-month follow-up. Sperm concentration, however, reduced after the procedure.


Assuntos
Cirurgia Bariátrica , Infertilidade Masculina , Obesidade Mórbida , Fragmentação do DNA , Hormônio Foliculoestimulante , Humanos , Infertilidade Masculina/etiologia , Hormônio Luteinizante , Masculino , Obesidade Mórbida/cirurgia , Estudos Prospectivos , Análise do Sêmen , Motilidade dos Espermatozoides , Espermatozoides
5.
Extremophiles ; 24(2): 219-225, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31732815

RESUMO

We surveyed the diversity of cultivable fungi isolated from cold and hot volcanic soils of Deception Island, Antarctica. Seventy-four fungal isolates were identified; these belonged to 17 taxa in the genera Aspergillus, Penicillium, Pseudogymnoascus, Purpureocillium, and Mortierella. The fungal assemblages showed low diversity, richness, and dominance indices. The Aspergillus taxa were dominant in the soils at 0 °C, 50 °C, and 100 °C. Aspergillus lacticoffeatus, Aspergillus cf. ruber, Penicillium citrinun, and Purpureocillium sodanum were present only in soils having a temperature of 100 °C. Aspergillus calidoustus was present in all thermal soils and displayed the highest densities. The majority of fungi displayed mesophilic behavior; however, different isolates of Aspergillus lacticoffeatus and Aspergillus niger were able to grow at 50 °C; these are phylogenetically close to the causative agents of aspergillosis in immunocompromised individuals. Deception Island perhaps represents one of the most visited regions in Antarctica and the tourism there has increased over the last 20 years, especially by elderly tourists, probably with weak immune systems, come in contact with the resident microorganisms, including the thermo-resistant opportunistic Aspergillus species.


Assuntos
Solo , Idoso , Regiões Antárticas , Ascomicetos , Fungos , Humanos , Ilhas , Microbiologia do Solo
6.
PLoS One ; 13(6): e0198452, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29883496

RESUMO

As marine ecosystems are influenced by global and regional processes, standardized information on community structure has become crucial for assessing broad-scale responses to natural and anthropogenic disturbances. Extensive biogeographic provinces, such as the Brazilian Province in the southwest Atlantic, present numerous theoretical and methodological challenges for understanding community patterns on a macroecological scale. In particular, the Brazilian Province is composed of a complex system of heterogeneous reefs and a few offshore islands, with contrasting histories and geophysical-chemical environments. Despite the large extent of the Brazilian Province (almost 8,000 kilometers), most studies of shallow benthic communities are qualitative surveys and/or have been geographically restricted. We quantified community structure of shallow reef habitats from 0° to 27°S latitude using a standard photographic quadrat technique. Percent cover data indicated that benthic communities of Brazilian reefs were dominated by algal turfs and frondose macroalgae, with low percent cover of reef-building corals. Community composition differed significantly among localities, mostly because of their macroalgal abundance, despite reef type or geographic region, with no evident latitudinal pattern. Benthic diversity was lower in the tropics, contrary to the general latitudinal diversity gradient pattern. Richness peaked at mid-latitudes, between 20°S to 23°S, where it was ~3.5-fold higher than localities with the lowest richness. This study provides the first large-scale description of benthic communities along the southwestern Atlantic, providing a baseline for macroecological comparisons and evaluation of future impacts. Moreover, the new understanding of richness distribution along Brazilian reefs will contribute to conservation planning efforts, such as management strategies and the spatial prioritization for the creation of new marine protected areas.


Assuntos
Recifes de Corais , Alga Marinha/fisiologia , Oceano Atlântico , Biodiversidade , Brasil
7.
Int Braz J Urol ; 38(3): 356-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22765853

RESUMO

OBJECTIVE: Partial nephrectomy for small kidney tumors has increased in the last decades, and the approach to non-palpable endophytic tumors became a challenge, with larger chances of positive margins or complications. The aim of this study is to describe an alternative nephron-sparing approach for small endophytic kidney tumors through anatrophic nephrotomy. PATIENTS AND METHODS: A retrospective analysis of patients undergoing partial nephrectomy at our institution was performed and the subjects with endophytic tumors treated with anatrophic nephrotomy were identified. Patient demographics, perioperative outcomes and oncological results were evaluated. RESULTS: Among the partial nephrectomies performed for intraparenchymal tumors between 06/2006 and 06/2010, ten patients were submitted to anatrophic nephrotomy. The mean patient age was 42 yrs, and the mean tumor size was 2.3 cm. Mean warm ischemia time was 22.4 min and the histopathological analysis showed 80% of clear cell carcinomas. At a mean follow-up of 36 months, no significant creatinine changes or local or systemic recurrences were observed. CONCLUSION: The operative technique described is a safe and effective nephron-sparing option for complete removal of endophytic renal tumors.


Assuntos
Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Néfrons/cirurgia , Tratamentos com Preservação do Órgão/métodos , Adulto , Carcinoma de Células Renais/patologia , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Carga Tumoral , Isquemia Quente
8.
Int. braz. j. urol ; 38(3): 356-361, May-June 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-643034

RESUMO

OBJECTIVE: Partial nephrectomy for small kidney tumors has increased in the last decades, and the approach to non-palpable endophytic tumors became a challenge, with larger chances of positive margins or complications. The aim of this study is to describe an alternative nephron-sparing approach for small endophytic kidney tumors through anatrophic nephrotomy. PATIENTS AND METHODS: A retrospective analysis of patients undergoing partial nephrectomy at our institution was performed and the subjects with endophytic tumors treated with anatrophic nephrotomy were identified. Patient demographics, perioperative outcomes and oncological results were evaluated. RESULTS: Among the partial nephrectomies performed for intraparenchymal tumors between 06/2006 and 06/2010, ten patients were submitted to anatrophic nephrotomy. The mean patient age was 42 yrs, and the mean tumor size was 2.3 cm. Mean warm ischemia time was 22.4 min and the histopathological analysis showed 80% of clear cell carcinomas. At a mean follow-up of 36 months, no significant creatinine changes or local or systemic recurrences were observed. CONCLUSION: The operative technique described is a safe and effective nephron-sparing option for complete removal of endophytic renal tumors.


Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Néfrons/cirurgia , Tratamentos com Preservação do Órgão/métodos , Carcinoma de Células Renais/patologia , Estudos de Viabilidade , Neoplasias Renais/patologia , Estudos Retrospectivos , Resultado do Tratamento , Carga Tumoral , Isquemia Quente
9.
An Acad Bras Cienc ; 84(1): 113-22, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22441600

RESUMO

Byrsonima sericea leaves are extensively used in folk medicine in Brazil against gastric disorders. This study investigated the chemical constituents of B. sericea leaf ethanolic extract (BSLE) and its potential gastroprotective activity, with its possible mechanism of the action using ethanol to induce gastric mucosal damage in mice. The phytochemical analysis was carried out to identify the active constituents present in the extract, and the HPLC analysis was performed for the identification of flavonoids. BSLE at oral doses of 125, 250 and 500 mg/kg markedly attenuated the ethanol-evoked gastric lesions by 53.2, 84.9 and 87.6 %, respectively. The BSLE (250 mg/kg) prevented the depletion of gastric mucus and gastric mucosal nonproteic-sulfhydryl groups, SOD and CAT, as well as the increase in the MDA content promoted by absolute ethanol. Moreover, the effect of BSLE against ethanol damage was found to be significantly reduced in mice pretreated with Capsazepine (i.p.), L-NAME (i.p.) or glibenclamide (i.p.), the respective blockers/inhibitors of TRPV1, NO synthase and K+ATP channel. The phytochemical investigation on BSLE revealed the presence of flavonoids rutin, isoquercitrin, kaempferol 3-O-rutinoside and quercetin, which are compounds well known for their antioxidant and gastroprotective properties. These results suggest that BSLE affords gastroprotection through multiple mechanisms, which may be helpful in the treatment of pathologies associated with gastric dysfunctions.


Assuntos
Antiulcerosos/uso terapêutico , Mucosa Gástrica/efeitos dos fármacos , Malpighiaceae/química , Extratos Vegetais/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Etanol/efeitos adversos , Feminino , Camundongos , Folhas de Planta/química , Úlcera Gástrica/induzido quimicamente
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