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1.
Cryo Letters ; 44(2): 110-108, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37883160

RESUMEN

BACKGROUND: The synergistic action among the different extracellular cryoprotectants could improve somatic cell quality after thawing and provide bases for the formation of biobanks for red-rumped agoutis. OBJECTIVE: This study evaluated the interactions among sucrose (SUC) and concentrations of serum fetal bovine (FBS) on the cryopreservation of somatic cells derived from red-rumped agoutis. MATERIALS AND METHODS: Cells were cryopreserved with 10% dimethyl sulfoxide and different concentrations of FBS (10%, 40%, and 90%) with or without 0.2 M SUC, totaling six comparison groups. Non-cryopreserved cells were used as a control. Cells were evaluated for viability, metabolic activity, proliferative activity, reactive oxygen species (ROS), mitochondrial membrane potential and apoptosis levels. RESULTS: No difference was observed among cryopreserved with DMSO containing (10FBS, 10FBS-SUC, 40FBS, 40FBS-SUC, 90FBS, 90FBS-SUC) and non-cryopreserved groups for viability, metabolic activity, proliferative activity, and ROS levels. Interestingly, only cells cryopreserved with 90% FBS and SUC maintained the mitochondrial membrane potential like the control. This indicates that at high concentrations of FBS, SUC contributes to the maintenance of this parameter in cryopreserved cells. Moreover, at concentrations of 10% and 40% of FBS, SUC contributed to the maintenance of viability evaluated by the levels of apoptosis evaluated after thawing. In summary, we verified that 90% FBS and 0.2 M SUC promote greater ability of cells after thawing. Additionally, SUC positively acts in cryopreservation solutions containing 10% and 40% FBS. CONCLUSION: This information is essential to an understanding of the mechanisms involved in the interactions of extracellular cryoprotectants in somatic cell cryopreservation solutions of red-rumped agoutis. DOI: 10.54680/fr23210110212.


Asunto(s)
Criopreservación , Dasyproctidae , Animales , Bovinos , Criopreservación/veterinaria , Sacarosa/farmacología , Especies Reactivas de Oxígeno , Crioprotectores/farmacología , Dimetilsulfóxido/farmacología , Supervivencia Celular
2.
Morphologie ; 105(348): 64-68, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32891508

RESUMEN

OBJECTIVE OF THE STUDY: The aim of this study was to assess the anatomical features of the alveolar antral artery (AAA) in edentulous patients using cone beam computed tomography (CBCT). PATIENTS: The sample consisted of 191 CBCT scans of maxillary sinuses (n=382) of male (n=59) and female (n=132) edentulous patients (age: 38-89 years). MATERIAL AND METHODS: The images were analyzed in Dolphin™ 11.9 software. Visualization, location, and diameter of the AAA was registered. RESULTS: AAA was present in 88.5% of the assessed maxillary sinuses. Bilateral visualization was predominant 77% (P<0.0001). The mean vertical distance from the most anterior part of the AAA to the sinus floor was 7.9±6mm in female patients (both sides) and 12±7.22mm on the right side and 10.9±6.86mm on the left side in males. The mean diameter of the AAA was 1.2±0.7mm on both sides in females. In males, the diameter was significantly (P<0.05) larger: 1.5±0.62mm on the right side and 1.4±0.69 on the left side in females. CONCLUSION: The AAA had a higher visualization rate, better visualization, and larger diameter when it was present bilaterally in male and female patients.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Adulto , Anciano , Anciano de 80 o más Años , Arterias , Femenino , Humanos , Masculino , Seno Maxilar , Persona de Mediana Edad , Elevación del Piso del Seno Maxilar , Programas Informáticos
3.
J Appl Microbiol ; 127(1): 237-247, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30989772

RESUMEN

AIMS: This study aimed to gather information on farming practices employed in organic lettuce fields in Sao Paulo, Brazil and associate these practices with the microbiological characteristics of the products. METHODS AND RESULTS: Practices were surveyed using a questionnaire applied in ten farms, where 200 heads of lettuce were collected and submitted to enumeration of total coliforms and generic Escherichia coli and tested for Salmonella spp. using culture and molecular (qPCR) methods. Based on the responses, the farms could be clustered in two groups: group 1, comprised by six farms, where chicken manure was used as fertilizer in most of them and the composting process was not performed on site; and group 2, comprised by four farms, where other types of fertilizer were used, and the composting process was performed on site. Generic E. coli was detected in 56 (28%) samples, with an average of 1·1 ± 0·7 log MPN per g. Salmonella DNA was detected in two (1%) samples by qPCR. CONCLUSIONS: The prevalence and bacterial loads of generic E. coli, and the occurrence of Salmonella, even at low populations undetectable by conventional culture methods, highlight the need for control measures during farming practices to reduce microbial contamination and risks of foodborne illnesses. These measures include the use of properly composted manure and appropriate washing procedures for leafy vegetables before consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: The obtained data contribute to a better understanding of the farming practices of organically grown lettuces in Sao Paulo, Brazil.


Asunto(s)
Escherichia coli/aislamiento & purificación , Microbiología de Alimentos , Lactuca/microbiología , Agricultura Orgánica/estadística & datos numéricos , Salmonella/aislamiento & purificación , Brasil , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Granjas , Humanos , Agricultura Orgánica/normas , Salmonella/genética , Salmonella/crecimiento & desarrollo
4.
J Mater Sci Mater Med ; 25(1): 229-37, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24072391

RESUMEN

It is of current interest the identification of appropriate matrices for growing mesenchymal stem cells (MSC). These cells are able not only to regenerate themselves but also to differentiate into other type of functional cells, and so they have been extensively used in tissue engineering. In this work, we have evaluated the use of electric impedance spectroscopy (EIS) to follow the adhesion of MSC from Wharton's jelly of the human umbilical cord (hWJMSC) on sugarcane biopolymers (SCB). Impedance spectra of the systems were obtained in the frequency range of 10(2)-10(5) Hz. An EIS investigation showed that when deposited on a metallic electrode SCB films prevent the passage of electrons between the solution and the metallic interface. The impedance spectra of hWJMSCs adhered on SCB revealed that there is a significant increase in the magnitude of the impedance when compared to that of pure SCB. The corresponding resistance (real part of the impedance) was even higher for the SCB-hWJMSC system than for SCB without cells on their surface, in an indication of an increased blockage to the electron transfers. The resistance charge transfer is extracted by curve-fitting the impedance spectra to an equivalent circuit model. Also, a shift of the phase angle to higher frequencies was obtained for SCB-hWJMSC system as a result from hWJMSC adhesion. Our study demonstrates that EIS is an appropriate method to evaluate the adhesion of MSC. SCB can be considered as a promising biomaterial for tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Biopolímeros/química , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Saccharum/química , Cordón Umbilical/citología , Adhesión Celular , Células Cultivadas , Impedancia Eléctrica , Femenino , Humanos , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Embarazo , Ingeniería de Tejidos , Gelatina de Wharton/citología
5.
Scand J Immunol ; 73(2): 112-21, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21198751

RESUMEN

Cramoll 1,4 is a lectin with specific glucose/mannose binding, which is extracted from seeds of Cratylia mollis Mart. Many assays have shown the cytokine expression activity and anti-inflammatory profile of this lectin. The aim of this study was to evaluate the immunostimulatory response, in vitro, of splenocytes in mice previously inoculated, in vivo, with C. mollis (Cramoll 1,4) and Canavalia ensiformis (Con A) lectins. Results demonstrated higher proliferation indexes induced by Cramoll 1,4 than Con A lectin in relation to all experimental groups. Cramoll 1,4 and Con A also induced high levels of IL-2, IL-6, IFN-γ and nitric oxide production. Moreover, Cramoll 1,4 did not induce apoptosis and stimulated a significant number of cells in the S phase of the cell cycle. Results showed that Cramoll 1,4 lectin induces proliferative response and suggested that this lectin can be used as a mitogenic agent in immunostimulatory assays.


Asunto(s)
Interferón gamma/inmunología , Interleucina-2/inmunología , Interleucina-6/inmunología , Mitosis , Lectinas de Plantas/inmunología , Bazo/citología , Bazo/inmunología , Animales , Proliferación Celular , Células Cultivadas , Interferón gamma/biosíntesis , Interleucina-2/biosíntesis , Interleucina-6/biosíntesis , Linfocitos/citología , Linfocitos/inmunología , Masculino , Ratones , Óxido Nítrico/biosíntesis
6.
Braz J Biol ; 82: e236345, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34105665

RESUMEN

A first checklist of Rotifera species in freshwater environments in Bahia State, in northeastern Brazil, is provided. The list includes sampling data from 26 aquatic environments (lotic and lentic) undertaken from 2010 to 2016. One hundred and fifty-five species were recorded, with 68 new records for the state. The family Brachionidae and Lecanidae were the most representative (54.8%). The greatest richness was recorded in the Colônia River (57 species). Those results reflect the low numbers of studies previously undertaken in the region, indicating more research needs to be focused on Rotifera biodiversity in Bahia, the fifth largest state in Brazil (567,295 km2) with large numbers of freshwater bodies.


Asunto(s)
Rotíferos , Animales , Biodiversidad , Brasil , Agua Dulce , Ríos
7.
Braz J Med Biol Res ; 54(10): e10730, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34287577

RESUMEN

Chondroitin sulfate (CS) is a type of glycosaminoglycan described as an antioxidant molecule that has been found in animal species such as fish. Tilapia (Oreochromis niloticus) represents an eco-friendly source of this compound, since its economical processing generates usable waste, reducing the negative environmental impact. This waste was used for CS extraction, purification, characterization by enzymatic degradation, and evaluation of its antioxidant effect. CS obtained from tilapia presented sulfation mainly at carbon 4 of galactosamine, and it was not cytotoxic at concentrations up to 200 µg/mL. Furthermore, 100 µg/mL of CS from tilapia reduced the levels of reactive oxygen species to 47% of the total intracellular reactive oxygen species level. The ability of CS to chelate metal ions in vitro also suggested an ability to react with other pathways that generate oxidative radicals, such as the Haber-Weiss reaction, acting intracellularly in more than one way. Although the role of CS from tilapia remains unclear, the pharmacological effects described herein indicate that CS is a potential molecule for further study of the relationship between the structures and functions of chondroitin sulfates as antioxidants.


Asunto(s)
Antioxidantes , Sulfatos de Condroitina , Animales , Antioxidantes/farmacología , Peces , Glicosaminoglicanos , Especies Reactivas de Oxígeno
8.
J Mol Model ; 27(5): 145, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33932166

RESUMEN

In this work, we report a theoretical study of the structural, electronic, and optical properties of palmitic acid crystal in its C form under DFT calculations level. Palmitic acid is a fatty acid that constitutes the large majority of vegetable oils with recognized potential applications in medicine, pharmaceuticals, cosmetics technology, foods, and fuel. As a main result, we have found that the electronic bandstructure reveals an indirect gap given by 3.713 eV (E→B andE→Γ), as a main bandgap, while the secondary bandgaps found were 4.175 eV (γ1→Γ) and 4.172 eV (γ2→B). It behaves like a wide bandgap semiconductor, which points to potential applications in optoelectronic devices.

9.
Animal ; 15(2): 100089, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33712220

RESUMEN

In general, calf production occurs in less intensive systems. The limitation of nutrients during the gestation phase of beef cows can have negative impacts on the consequent productivity of females. Therefore, this study aimed to evaluate the effects of nutritional levels in the third trimester of pregnancy on the productive performance of beef cows kept in a natural pasture (NP). Eighty-three Charolais × Nelore cows were used, ranging in age from 4 to 12 years, which were divided according to their nutritional levels during the third trimester of pregnancy: NP, cows supplemented with 100% of their energy and protein requirements (SP100) and cows supplemented with 150% of their energy and protein requirements (SP150). The experimental design was completely randomized with three treatments and a varied number of repetitions. The SP100 and SP150 cows presented better body condition at calving (2.92 and 2.99 vs 2.81 points) and at the start of the breeding season (2.90 and 2.95 vs 2.80 points) than did NP cows. The nutritional level of the cows in the third trimester of gestation did not influence the blood metabolite concentrations. The plasma levels of albumin and total proteins were 3.11 and 8.18 g/dl, respectively. Glucose and cholesterol showed values of 74.96 and 166.50 mg/dl. The lowest concentration of blood metabolites was observed in the first postpartum weeks. The SP100 and SP150 cows showed faster follicular growth and, consequently, a higher percentage of females with ovulatory follicles at 21 days postpartum than did NP cows (45.68, 41.11, and 11.00%, respectively). The SP150 cows had a higher pregnancy rate (40.74%), total calf production (295.88 kg/cow), and consequently, offspring sale value. An increased nutritional level in the third trimester of pregnancy improves the postpartum metabolic condition and productive efficiency of beef cows kept on NP.


Asunto(s)
Suplementos Dietéticos , Periodo Posparto , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos , Dieta/veterinaria , Femenino , Lactancia , Embarazo , Índice de Embarazo , Estaciones del Año
10.
Vet Parasitol ; 155(1-2): 95-103, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18513872

RESUMEN

Cellular and humoral immune response, as well as cytokine gene expression, was assessed in Nelore cattle with different degrees of resistance to Cooperia punctata natural infection. One hundred cattle (male, weaned, 11-12 months old), kept together on pasture, were evaluated. Faecal and blood samples were collected for parasitological and immunological assays. Based on nematode faecal egg counts (FEC) and worm burden, the seven most resistant and the eight most susceptible animals were selected. Tissue samples of the small intestine were collected for histological quantification of inflammatory cells and analysis of cytokine gene expression (IL-2, IL-4, IL-8, IL-12p35, IL-13, TNF-alpha, IFN-gamma, MCP-1, MCP-2, and MUC-1) using real-time RT-PCR. Mucus samples were also collected for IgA levels determination. Serum IgG1 mean levels against C. punctata antigens were higher in the resistant group, but significant differences between groups were only observed 14 days after the beginning of the experiment against infective larvae (L3) and 14 and 84 days against adult antigens. The resistant group also presented higher IgA levels against C. punctata (L3 and adult) antigens with significant difference 14 days after the beginning of the trial (P<0.05). In the small-intestine mucosa, levels of IgA anti-L3 and anti-adult C. punctata were higher in the resistant group, compared with the susceptible group (P<0.05). Gene expression of both T(H)2 cytokines (IL-4 and IL-13) in the resistant group and T(H)1 cytokines (IL-2, IL-12p35, IFN-gamma and MCP-1) in the susceptible group was up-regulated. Such results suggested that immune response to C. punctata was probably mediated by T(H)2 cytokines in the resistant group and by T(H)1 cytokines in the susceptible group.


Asunto(s)
Enfermedades de los Bovinos/genética , Citocinas/metabolismo , Perfilación de la Expresión Génica/veterinaria , Predisposición Genética a la Enfermedad , Infecciones por Nematodos/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Citocinas/genética , Regulación de la Expresión Génica/fisiología , Inmunoglobulina A , Infecciones por Nematodos/inmunología , Infecciones por Nematodos/parasitología
12.
Genet Mol Res ; 6(2): 415-21, 2007 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-17952865

RESUMEN

Studies of the hemoglobin pattern in Brazilian reptiles are important for determining ecological and phylogenetic relationships, but they are scarce. Peripheral blood samples were obtained from 7 males and 18 females of Rhinoclemmys punctularia. The hematological profile was based on the total hemoglobin and hematocrit values. The hemoglobin profile was obtained using electrophoretic procedures at different pH, isoelectric focusing, globin chain electrophoresis, and HPLC. The hematocrit (31 +/- 2%) and total hemoglobin (7.5 +/- 0.2 g/dL) values did not indicate gender variations. Alkaline pH electrophoresis of the total blood samples treated with 1% saponin demonstrated the presence of four well-defined hemoglobin fractions, one major component (fraction I), showing cathodic migration and three others faster than fraction I with anodic migration. When the samples were precipitated with chloroform, only two hemoglobin fractions were observed, similar to fractions I and III from the first procedure. Isoelectric focusing and HPLC showed the same pattern. With acid and neutral pH electrophoresis, two fractions with anodic migration were observed. The globin chain identification at alkaline pH showed two fractions, but four fractions were observed at acidic pH, suggesting that different polypeptide chains are involved in the hemoglobin molecule. The chromatographic separation of the total blood sample demonstrated that the major fraction comprised 81.9% and the minor 18.1%. The results obtained demonstrated a similarity between these hemoglobin components and those of some Chelidae reported in the literature for both land and aquatic animals, reflecting the adaptation to environmental conditions.


Asunto(s)
Cromatografía/métodos , Electroforesis/métodos , Hemoglobinas/genética , Hemoglobinas/metabolismo , Polimorfismo Genético , Tortugas/genética , Animales , Ecología/métodos , Femenino , Hematócrito , Humanos , Masculino , Modelos Genéticos , Filogenia , Reptiles
13.
Braz J Med Biol Res ; 39(5): 595-602, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16648896

RESUMEN

Hepatitis C virus (HCV) infection has been identified as the major cause of chronic liver disease among patients on chronic hemodialysis (HD), despite the important reduction in risks obtained by testing candidate blood donors for anti-HCV antibodies and the use of recombinant erythropoietin to treat anemia. A cross-sectional study was performed to estimate the prevalence of HCV infection and genotypes among HD patients in Salvador, Northeastern Brazil. Anti-HCV seroprevalence was determined by ELISA in 1243 HD patients from all ten different dialysis centers of the city. HCV infection was confirmed by RT-PCR and genotyping was performed by restriction fragment length polymorphism. Anti-HCV seroprevalence among HD patients was 10.5% (95% CI: 8.8-12.3) (Murex anti-HCV, Abbott Murex, Chicago, IL, USA). Blood samples for qualitative HCV detection and genotyping were collected from 125/130 seropositive HD patients (96.2%). HCV-RNA was detected in 92/125 (73.6%) of the anti-HCV-positive patients. HCV genotype 1 (77.9%) was the most prevalent, followed by genotype 3 (10.5%) and genotype 2 (4.6%). Mixed infections of genotypes 1 and 3 were found in 7.0% of the total number of patients. The present results indicate a significant decrease in anti-HCV prevalence from 23.8% detected in a study carried out in 1994 to 10.5% in the present study. The HCV genotype distribution was closely similar to that observed in other hemodialysis populations in Brazil, in local candidate blood donors and in other groups at risk of transfusion-transmitted infection.


Asunto(s)
Genotipo , Hepacivirus/genética , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/epidemiología , Diálisis Renal/efectos adversos , Brasil/epidemiología , Estudios Transversales , Electroforesis en Gel de Agar , Ensayo de Inmunoadsorción Enzimática , Hepacivirus/inmunología , Hepatitis C/diagnóstico , Hepatitis C/etiología , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , ARN Viral/análisis , Estudios Seroepidemiológicos
14.
Braz. j. med. biol. res ; 54(10): e10730, 2021. graf
Artículo en Inglés | LILACS | ID: biblio-1285651

RESUMEN

Chondroitin sulfate (CS) is a type of glycosaminoglycan described as an antioxidant molecule that has been found in animal species such as fish. Tilapia (Oreochromis niloticus) represents an eco-friendly source of this compound, since its economical processing generates usable waste, reducing the negative environmental impact. This waste was used for CS extraction, purification, characterization by enzymatic degradation, and evaluation of its antioxidant effect. CS obtained from tilapia presented sulfation mainly at carbon 4 of galactosamine, and it was not cytotoxic at concentrations up to 200 µg/mL. Furthermore, 100 µg/mL of CS from tilapia reduced the levels of reactive oxygen species to 47% of the total intracellular reactive oxygen species level. The ability of CS to chelate metal ions in vitro also suggested an ability to react with other pathways that generate oxidative radicals, such as the Haber-Weiss reaction, acting intracellularly in more than one way. Although the role of CS from tilapia remains unclear, the pharmacological effects described herein indicate that CS is a potential molecule for further study of the relationship between the structures and functions of chondroitin sulfates as antioxidants.


Asunto(s)
Animales , Sulfatos de Condroitina , Antioxidantes/farmacología , Especies Reactivas de Oxígeno , Peces , Glicosaminoglicanos
15.
J Anim Sci ; 94(1): 412-23, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26812347

RESUMEN

The objective of this study was to evaluate the effect of steak location and postmortem aging on cooked meat tenderness and myofibrillar protein degradation of steaks from M. semitendinosus (ST). Following harvest and a 6 d chill period, the left ST was removed from carcasses of crossbred feedlot steers ( = 60, average hot carcass weight 427 ± 24 kg). Each ST was fabricated into ten 2.54-cm thick steaks originating from the proximal to distal end of the muscle. Steaks cut adjacent to each other were paired, vacuum packaged, and randomly assigned to 7, 14, 21, 42, or 70 d of aging at 2 ± 1°C. After aging, within each steak pair, steaks were randomly assigned to Warner-Bratzler shear force or myofibrillar proteolysis analysis (calpain activity and desmin and troponin-T degradation). Muscle fiber type and size were also determined at the 2 ends of the muscle. There was no location × d of aging interaction ( = 0.25) for ST steak WBSF. Steak location affected (quadratic, < 0.01) WBSF. As steaks were fabricated from the proximal to distal end, WBSF values decreased toward the middle of the muscle and then increased toward the distal end. Activity of all calpains and myofibrillar protein proteolysis were unaffected by steak location ( > 0.13). Type I, IIA, and IIX muscle fibers were larger at the proximal end of the muscle than the distal end ( < 0.01). Increasing d of aging improved WBSF (quadratic, < 0.01) for the duration of the 70 d postmortem period. As d of aging increased, intact calpain-1 activity decreased (quadratic, < 0.01) with activity detected through 42 d. Day of aging affected autolyzed calpain-1 (linear, < 0.01) and calpain-2 activity (quadratic, < 0.01). Through d 70 of aging, the intensity of intact 55 kDa desmin band decreased (linear, < 0.01), while there was an increase (linear, < 0.01) in the degraded 38 kDa band. Similarly, d of aging increased troponin-T proteolysis, indicated by a decrease (quadratic, < 0.01) in intensity of the intact 40 kDa band and an increase (linear, < 0.01) in the 30 kDa degraded band. Intramuscular WBSF differences are not due to proteolytic activity or myofibrillar degradation and seem related to muscle fiber size. The improvement of ST steak WBSF through 70 d of aging is partly due to continued degradation of desmin and troponin-T. Calpain proteolytic analysis indicates that autolyzed calpain-1 and calpain-2 may be involved in extended postmortem myofibrillar protein proteolysis.


Asunto(s)
Carne/análisis , Músculo Esquelético/fisiología , Envejecimiento , Animales , Calpaína , Bovinos , Culinaria , Desmina , Almacenamiento de Alimentos , Masculino , Cambios Post Mortem , Proteolisis , Estrés Mecánico , Factores de Tiempo , Troponina T
16.
Int J Cardiol ; 222: 569-575, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27513653

RESUMEN

UNLABELLED: Aldosterone plays a pivotal role in the pathophysiology of systolic heart failure. However, whether early aldosterone antagonism improves cardiac remodeling during persistent pressure overload is unsettled. We evaluated the effects of aldosterone antagonist spironolactone on cardiac remodeling in rats with ascending aortic stenosis (AS). METHODS: Three days after inducing AS, weaning rats were randomized to receive spironolactone (AS-SPR, 20mg/kg/day) or no drug (AS) for 18weeks, and compared with sham-operated rats. Myocardial function was studied in isolated left ventricular (LV) papillary muscles. STATISTICAL ANALYSES: ANOVA or Kruskal-Wallis tests. RESULTS: Echocardiogram showed that LV diastolic (Sham 8.73±0.57; AS 8.30±1.10; AS-SPR 9.19±1.15mm) and systolic (Sham 4.57±0.67; AS 3.61±1.49; AS-SPR 4.62±1.48mm) diameters, left atrial diameter (Sham 5.80±0.44; AS 7.15±1.22; AS-SPR 8.02±1.17mm), and LV mass were higher in AS-SPR than AS. Posterior wall shortening velocity (Sham 38.5±3.8; AS 35.6±5.6; AS-SPR 31.1±3.8mm/s) was lower in AS-SPR than Sham and AS; E/A ratio was higher in AS-SPR than Sham. Developed tension was lower in AS and AS-SPR than Sham. Time to peak tension was higher in AS-SPR than Sham and AS after post-rest contraction. Right ventricle weight was higher in AS-SPR than AS, suggesting more severe heart failure in AS-SPR than AS. Interstitial collagen fractional area and myocardial hydroxyproline concentration were higher in AS than Sham. Metalloproteinase-2 and -9 activity, evaluated by zymography, did not differ between groups. CONCLUSION: Early spironolactone administration causes further hypertrophy in cardiac chambers, and left ventricular dilation and dysfunction in rats with AS-induced chronic pressure overload.


Asunto(s)
Aldosterona/fisiología , Estenosis de la Válvula Aórtica/fisiopatología , Cardiomegalia/fisiopatología , Antagonistas de Receptores de Mineralocorticoides/toxicidad , Remodelación Ventricular/fisiología , Animales , Estenosis de la Válvula Aórtica/inducido químicamente , Cardiomegalia/inducido químicamente , Electrocardiografía/efectos de los fármacos , Electrocardiografía/tendencias , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar , Espironolactona/toxicidad , Resultado del Tratamiento , Remodelación Ventricular/efectos de los fármacos
17.
PLoS One ; 10(6): e0127176, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26061735

RESUMEN

The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and closed pools suggest that the dynamics in open pools is mostly driven by physical factors and the tolerance of organisms to harsh conditions, while in closed pools direct and indirect effects of species interactions also play an important role. Understanding the mechanisms shaping biological communities and how they scale-up to ecosystem functioning is particularly important on isolated near-pristine systems where natural processes can still be studied under limited human impact.


Asunto(s)
Arrecifes de Coral , Ecosistema , Conducta Alimentaria , Peces/fisiología , Animales , Océano Atlántico , Brasil , Presión
18.
Surgery ; 114(4): 673-9; discussion 679-81, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8211681

RESUMEN

BACKGROUND: The indications for shunt placement to prevent cerebral ischemia during carotid endarterectomy have been controversial. Some investigators have recommended empiric shunting for patients presumed to be at higher risk for cerebral ischemia with a recent stroke or severe stenosis or occlusion of the contralateral internal carotid artery. METHODS: Carotid endarterectomy was performed in 81 cases with cervical block anesthetic, monitoring the awake patient for the development of cerebral ischemia (unresponsiveness or paralysis) during carotid clamping. The need for shunting (based on awake response) was compared in patients with the arbitrarily defined empiric indications for shunting (n = 29) versus those who did not have such clinical or anatomic findings (n = 52). RESULTS: Cerebral ischemia requiring shunting was observed in five (17.2%) of 29 cases with the defined indications for empiric shunting. This was not different than the need for shunting in the control group where cerebral ischemia was seen in eight (15.4%) of 52 cases. No intraoperative neurologic events occurred in any case, but one (1.2%) patient suffered a postoperative transient ischemia attack and another (1.2%) had a postoperative stroke. CONCLUSIONS: Empiric clinical or anatomic indications for shunting were not reliable predictors of cerebral ischemia that developed during carotid clamping in this study. Awake patient monitoring during carotid endarterectomy with regional anesthetic allowed prompt, accurate identification of patients with cerebral ischemia who would clearly benefit from placement of a shunt.


Asunto(s)
Endarterectomía Carotidea , Monitoreo Intraoperatorio , Anciano , Anestesia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Arterias Carótidas/diagnóstico por imagen , Angiografía Cerebral , Plexo Cervical , Electroencefalografía , Diseño de Equipo , Femenino , Humanos , Masculino , Monitoreo Intraoperatorio/instrumentación , Bloqueo Nervioso/efectos adversos , Complicaciones Posoperatorias
19.
Arch Surg ; 131(5): 472-80, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8624191

RESUMEN

BACKGROUND: Patients who undergo neurosurgical procedures are at high risk for perioperative deep vein thrombosis (DVT) and pulmonary embolism (PE), which have been reported in 6% to 43% of these patients. OBJECTIVES: To (1) determine the utility of prospective DVT surveillance in patients who undergo neurosurgical procedures by using venous duplex ultrasound scanning (VDUS), (2) assess the efficacy of DVT prophylaxis (elastic stockings and intermittent pneumatic compression), (3) identify subgroups of patients who are at higher risk, and (4) determine whether DVT surveillance would reduce the incidence of fatal PE. DESIGN: All patients had undergone preoperative VDUS of both lower extremities, and postoperative VDUS was performed on days 3 and 7, and weekly thereafter until patients were ambulatory or discharged. PATIENTS: During a 5-year period, 2643 patients who underwent neurosurgical procedures were enrolled in prospective DVT surveillance. SETTING: University-affiliated community hospital. RESULTS: Acute DVT was diagnosed in 147 (5.6%) of the 2643 patients. Eighty-one percent of the patients with acute DVT were asymptomatic at the time of diagnosis. Deep vein thrombosis developed de novo in the proximal veins in 98% of the patients. Patients in whom a craniotomy was done had a significantly higher risk for DVT (7.7%, P = .006), and patients who underwent cervical or lumbar spinal surgical procedures had a significantly lower risk (1.5%, P < .001). Among those patients in whom a craniotomy was performed for treatment of a tumor and who had DVT, 87% had malignant neoplasms. Significant lower-extremity neuromotor dysfunction was present in 69% of all patients with DVT, and this finding predominated among patients with DVT in the subgroups with a lower risk. A PE was diagnosed in 5 patients (0.19%) while they were hospitalized, and a PE was fatal in 2 (0.07% of all patients). CONCLUSIONS: Most perioperative DVTs were clinically silent and formed spontaneously in proximal venous segments where there would be a risk for a PE. The overall incidence of DVT (5.6%) was low, suggesting effective DVT prophylaxis. Patients who underwent spinal surgical procedures were at a significantly lower risk for DVT, and future surveillance is not indicated in this patient group unless other conditions exist (paralysis, malignancy). Patients in whom a craniotomy was performed had a significantly higher risk of DVT, particularly when other risk factors existed. The low incidence of a fatal PE (0.07%) reflected that early detection and treatment of proximal DVT were facilitated by prospective VDUS surveillance in these patients.


Asunto(s)
Procedimientos Neuroquirúrgicos , Complicaciones Posoperatorias/diagnóstico por imagen , Tromboembolia/diagnóstico por imagen , Ultrasonografía Doppler Dúplex , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Vendajes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/etiología , Tromboembolia/complicaciones , Tromboembolia/prevención & control
20.
Urology ; 49(1): 46-9, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9000184

RESUMEN

OBJECTIVES: To determine the acceptance of the self-administered International Prostate Symptom Score (IPSS) by people of differing educational levels in two different countries. METHODS: The questionnaire adopted by the World Health Organization and known as the IPSS attempts to measure the severity of lower urinary tract symptoms in men with benign prostatic hyperplasia. An international study was performed in Brazil and Argentina and included 768 patients. The IPSS was self-administered and used to evaluate and quantify the clinical symptoms resulting from benign prostatic hyperplasia. The patients were asked not to answer any questions that they did not clearly understand or about which they were unsure of the information they should give. The patients were assessed into two subgroups according to their level of education. The Brazilian group consisted of 458 men in which subgroup 1 was composed of 244 (53%) men who had an elementary school education, whereas subgroup 2 consisted of 214 (47%) men who had a higher education level, including a university degree. The Argentinian group consisted of 310 patients, 158 (51%) of whom had an elementary school education, whereas the remaining 152 (49%) had received higher education, including a university degree. RESULTS: A total of 77 men (16.8%), 35 (45.5%) from subgroup 1 and 42 (54.5%) from subgroup 2, failed to complete the questionnaire. The difference between the two subgroups was not significant. A total of 189 questions were not answered. There was no significant difference among the three questions most frequently unanswered by each subgroup. A total of 40 (12.9%) men filled out the questionnaire incompletely, 31 (77.5%) in the lower-education subgroup and 9 (22.5%) in the higher-education subgroup. An incomplete questionnaire was more frequent among the patients with lower education (P < 0.01). CONCLUSIONS: In spite of the cultural variations, there was no significant difference in the number of patients unable to answer the questionnaire in the two countries.


Asunto(s)
Hiperplasia Prostática/diagnóstico , Encuestas y Cuestionarios , Anciano , Argentina , Brasil , Humanos , Masculino , Persona de Mediana Edad
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