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2.
Nat Prod Res ; : 1-9, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932254

RESUMO

5α,8α-peroxyergosteryl divaricatinate (1) is isolated for the first time from acetone extract of the thallus of Cladonia cf. didyma together with condidymic (2), isodidymic (3) and barbatic (4) acids. Their UVB/UVA photoprotective and antioxidant activities were determined along with their cyto- and DNA-protecting actions against OH• damage. Compound 1 showed high UVA, cyto- (%cell viability ca. 82 at 15 µM vs 71 for OH•) and DNA (%DNA-integrity ca. 74 at 100 µM vs 22 for OH•) protecting properties. Compounds 2 and 3 exhibited high UVB (SPF ca. 40) and antioxidant activities (free radical scavenging potency EC50 = 0.6694 and 1.700 mol compound/mol DPPH•; ferric reducing power 0.392 and 0.546, at 500 ppm and inhibited lipid peroxidation); protecting cells (%cell viability ca. 76 at 15 µM) and DNA (%DNA-integrity ca. 57 at 100 µM). Compounds 1 to 3 fulfilled some physicochemical properties to act topically on the skin.

3.
Sensors (Basel) ; 22(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35590910

RESUMO

The research presents the inter-comparison of atmospheric variables measured by 9 automatic weather stations. This set of data was compared with the measurements of other weather stations in order to standardize the values that must be adjusted when taken to different areas. The data of a set of a total of 9 GMX500, which measures conventional meteorological variables, and 10 WS100 sensors, which measures precipitation parameters. The automatic stations were set up at the Huancayo Observatory (Geophysical Institute of Peru) for a period of 5 months. The data set of GMX500 were evaluated comparing with the average of the 9 sensors and the WS100 was compared with an optical disdrometer Parsivel2. The temperature, pressure, relative humidity, wind speed, rainfall rate, and drop size distribution were evaluated. A pair of GMX500 sensors presented high data dispersion; it was found found that the errors came from a bad configuration; once this problem was solved, good agreement was archived, with low RMSE and high correlation. It was found that the WS100 sensors overestimate the precipitation with a percentage bias close to 100% and the differences increase with the greater intensity of rain. The drop size distribution retrieved by WS100 have unrealistic behavior with higher concentrations in diameters of 1 mm and 5 mm, in addition to a flattened curve.


Assuntos
Chuva , Tempo (Meteorologia) , Umidade , Peru , Temperatura , Vento
4.
Ann Hepatol ; 18(2): 325-330, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31010794

RESUMO

INTRODUCTION AND AIM: The MELD score has been established as an efficient and rigorous prioritization system for liver transplant (LT). Our study aimed to evaluate the effectiveness of the MELD score as a system for prioritization for LT, in terms of decreasing the dropout rate in the waiting list and maintaining an adequate survival post-LT in Chile. MATERIALS AND METHODS: We analyzed the Chilean Public Health Institute liver transplant registry of candidates listed from October 15th 2011 to December 31st 2014. We included adult candidates (>15 years old) listed for elective cadaveric LT with a MELD score of 15 or higher. Statistical analysis included survival curves (Kaplan-Meier), log-rank statistics and multivariate logistic regression. RESULTS: 420 candidates were analyzed. Mean age was 53.6±11.8 years, and 244 were men (58%). Causes of LT included: Liver cirrhosis without exceptions (HC) 177 (66.4%); hepatocellular carcinoma (HCC) 111 (26.4%); cirrhosis with non-HCC exceptions 102 (24.3%) and non-cirrhotic candidates 30 (7.2%). LT rate was 43.2%. The dropout rate was 37.6% at 1-year. Even though the LT rate was higher, the annual dropout rate was significantly higher in cirrhotic candidates (without exceptions) compared with cirrhotics with HCC, and non-HCC exceptions plus non-cirrhotic candidates (47.9%; 37.2% and 24.2%, respectively, with p=0.004). Post-LT survival was 84% per year, with no significant differences between the three groups (p=0.95). CONCLUSION: Prioritization for LT using the MELD score system has not decreased the dropout rate in Chile (persistent low donor's rate). Exceptions generate inequities in dropout rate, disadvantaging patients without exceptions.


Assuntos
Comportamento Cooperativo , Técnicas de Apoio para a Decisão , Indicadores Básicos de Saúde , Disparidades em Assistência à Saúde/organização & administração , Comunicação Interdisciplinar , Transplante de Fígado , Obtenção de Tecidos e Órgãos/organização & administração , Adolescente , Adulto , Idoso , Chile , Tomada de Decisão Clínica , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Seleção de Pacientes , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Listas de Espera , Adulto Jovem
5.
Am J Surg ; 218(5): 993-999, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30665612

RESUMO

BACKGROUND: Hypocalcemia is one of the most common complications after total thyroidectomy. Recently, indocyanine green (ICG) angiography of the parathyroid glands (PGs) has been suggested as a reliable tool for predicting postoperative hypocalcemia. The aim of our study was to evaluate the performance of a simple quantitative score based on ICG angiography of the PGs (4-ICG score) for predicting postoperative hypocalcemia. METHODS: Thirty nine consecutive patients who underwent total thyroidectomy for multinodular goiter were included. For each patient, the 4-ICG score was calculated, adding the individual viability value of the four PGs. Discrimination and correlation analyses were performed. RESULTS: In 32/39 patients, the four PGs were identified. Patients with postoperative hypocalcemia (n = 6, 19%) had a lower 4-ICG score (2.5 [1.8-3.3] vs. 4.0 [3.0-6.0]; p = 0.003). The 4-ICG score showed good discrimination in terms of predicting postoperative hypocalcemia (AUC = 0.875 (0.710-0.965); p = 0.001) and a good correlation with postoperative parathyroid function. CONCLUSIONS: The 4-ICG score predicts postoperative hypocalcemia and correlates well with postoperative parathyroid function in patients undergoing total thyroidectomy for multinodular goiter.


Assuntos
Angiografia/métodos , Hipocalcemia/etiologia , Glândulas Paratireoides/irrigação sanguínea , Glândulas Paratireoides/diagnóstico por imagem , Tireoidectomia/efeitos adversos , Adulto , Idoso , Corantes , Feminino , Humanos , Verde de Indocianina , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
6.
Nat Prod Res ; 32(12): 1375-1382, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28691874

RESUMO

The new hypotrachynin A (1) and B (2) along with the known (+)-(9b-R)-usnic (3) and methylstictic acids (4) were isolated for the first time from Hypotrachyna caraccensis. Additionally, their potency and reactivity as DPPH• scavengers was determined by a kinetic study calculating their EC50 and second-order rate constants (k2). Considering 1-4 could be dermatological agents, their n-octanol-water partition coefficients and standard molar Gibbs free energies of transfer were calculated as estimation of their lipophilicity and skin penetration. Compounds 1, 3 and 4 were less potent than 2 (EC50 = 3.3014; 1.7540; 2.6652 vs 0.7376) as DPPH• scavengers, in turn 4, was the most reactive with a comparable k2 to the antioxidant BHT (k2 = (232 ± 24) × 10-2 vs (564 ± 12) × 10-2 M-1 s-1, respectively). Since 2 and 4 had an optimal lipophilicity and permeability for skin penetration, they might be developed as topical ingredients to prevent oxidative damage.


Assuntos
Ascomicetos/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Líquens/química , Antioxidantes/química , Colômbia , Depsídeos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Ecossistema , Radicais Livres , Estrutura Molecular , Resorcinóis/química
7.
Photochem Photobiol Sci ; 16(6): 954-971, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28470249

RESUMO

Ultraviolet (UV) solar irradiance measurements performed in the central Andes, Huancayo, Peru (12.0°S, 75.3°W, 3313 m asl) at 1 min intervals between January 2003 and December 2006 were used to analyse daily, monthly, and annual cycles of UV solar irradiance. The measurements were performed using a GUV-511 multi-channel filter radiometer at four wavelengths: 305, 320, 340, and 380 nm. UV irradiance data under clear sky and all sky conditions were separated using a procedure based on calculation of normalized irradiance. In February, the highest hourly mean value at noon for the UV Index reached 18.8 for clear sky conditions and 15.5 for all sky conditions, with outlier peaks close to UVI = 28. In addition, the highest mean value for the daily erythemal dose was found also in February, reaching 7.5 kJ m-2 d-1 with a maximum outlier value close to 10.1 kJ m-2 d-1. Comparisons between the clear sky GUV measurements and TUV model estimations were evaluated with statistical quantities showing values of R2 close to 0.98. The total ozone column and trace gases were obtained from OMI. The aerosol parameters were obtained from MODIS. The enhancements due to clouds of spectral irradiance at 340 nm as compared to a cloudless sky reach maxima of 20%. These results indicate that tropical central Andes has among the highest incident ultraviolet solar radiation in the world.

8.
Vector Borne Zoonotic Dis ; 15(3): 202-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25793476

RESUMO

Leishmaniasis is a serious problem that affects mostly poor countries. Various species of Leishmania are the agents of the disease, which take different clinical manifestations. The parasite is transmitted by sandflies, predominantly from the Phlebotomus genus in the Old World and Lutzomyia in the New World. During development in the gut, Leishmania must survive various challenges, which include avoiding being expelled with blood remnants after digestion. It is believed that attachment to the gut epithelium is a necessary step for vector infection, and molecules from parasites and sand flies have been implicated in this attachment. In previous work, monoclonal antibodies were produced against Leishmania. Among these an antibody was obtained against Leishmania braziliensis flagella, which blocked the attachment of Leishmania panamensis flagella to Phlebotomus papatasi guts. The protein recognized by this antibody was identified and named FLAG1, and the complete FLAG1 gene sequence was obtained. This protein was later independently identified as a small, myristoylated protein and called SMP1, so from now on it will be denominated FLAG1/SMP1. The FLAG1/SMP1 gene is expressed in all developmental stages of the parasite, but has higher expression in promastigotes. The anti-FLAG1/SMP1 antibody recognized the flagellum of all Leishmania species tested and generated the expected band by western blots. This antibody was used in attachment and infection blocking experiments. Using the New World vector Lutzomyia longipalpis and Leishmania infantum chagasi, no inhibition of attachment ex vivo or infection in vivo was seen. On the other hand, when the Old World vectors P. papatasi and Leishmania major were used, a significant decrease of both attachment and infection were seen in the presence of the antibody. We propose that FLAG1/SMP1 is involved in the attachment/infection of Leishmania in the strict vector P. papatasi and not the permissive vector L. longipalpis.


Assuntos
Regulação da Expressão Gênica/fisiologia , Leishmania/fisiologia , Proteínas de Protozoários/metabolismo , Psychodidae/parasitologia , Sequência de Aminoácidos , Animais , Western Blotting , Imunofluorescência , Interações Hospedeiro-Parasita , Leishmania/genética , Leishmania/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Protozoários/genética
9.
Clin Lymphoma Myeloma Leuk ; 14(4): 305-18, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24468131

RESUMO

BACKGROUND: We have evaluated the ex vivo pharmacology of single drugs and drug combinations in malignant cells of bone marrow samples from 125 patients with acute myeloid leukemia using a novel automated flow cytometry-based platform (ExviTech). We have improved previous ex vivo drug testing with 4 innovations: identifying individual leukemic cells, using intact whole blood during the incubation, using an automated platform that escalates reliably data, and performing analyses pharmacodynamic population models. PATIENTS AND METHODS: Samples were sent from 24 hospitals to a central laboratory and incubated for 48 hours in whole blood, after which drug activity was measured in terms of depletion of leukemic cells. RESULTS: The sensitivity of single drugs is assessed for standard efficacy (EMAX) and potency (EC50) variables, ranked as percentiles within the population. The sensitivity of drug-combination treatments is assessed for the synergism achieved in each patient sample. We found a large variability among patient samples in the dose-response curves to a single drug or combination treatment. CONCLUSION: We hypothesize that the use of the individual patient ex vivo pharmacological profiles may help to guide a personalized treatment selection.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Pessoa de Meia-Idade , Medicina de Precisão , Resultado do Tratamento
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