Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Sci Rep ; 13(1): 7923, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193722

RESUMO

Drug repositioning explores the reuse of non-cancer drugs to treat tumors. In this work, we evaluated the effect of the combination of chloroquine and propranolol on colorectal and triple-negative breast cancers. Using as in vitro models the colorectal cancer cell lines HCT116, HT29, and CT26, and as triple-negative breast cancer models the 4T1, M-406, and MDA-MB-231 cell lines, we evaluated the effect of the drugs combination on the viability, apoptosis, clonogenicity, and cellular migratory capacity. To explore the in vivo effects of the combination on tumor growth and metastasis development we employed graft models in BALB/c, nude, and CBi mice. In vitro studies showed that combined treatment decreased cell viability in a dose-dependent manner and increased apoptosis. Also, we demonstrated that these drugs act synergically and that it affects clonogenicity and migration. In vivo studies indicated that this drug combination was effective on colorectal models but only partially on breast cancer. These results contributed to the search for new and safe treatments for colorectal and triple-negative carcinomas.


Assuntos
Neoplasias Colorretais , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/patologia , Propranolol/farmacologia , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Apoptose , Neoplasias Colorretais/tratamento farmacológico , Proliferação de Células
2.
Trop Anim Health Prod ; 55(2): 75, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36763256

RESUMO

This study aimed at assessing farmers' perceptions and acceptance of the proposed breeding strategy of Instituto Veterinario de Investigaciones Tropicales y de Altura (IVITA), located in the Central Andes of Peru. A total of 34 farmers, who had received guinea pigs from IVITA, were interviewed. The questionnaire was performed in Spanish language and covered topics about the guinea pig production, feeding, mating system, training, the main products, perception and acceptance of crossbred lines ("cuy RG"), and the farmers' comment about the terminal crossbred animal ("cuy G"). The preferred feeding strategy was a combination of forage and supplement. All farmers implemented a controlled mating system. Most farmers had received training on feeding, reproduction, management, equipment, and facilities. The main product is animals for slaughter. The 82.40% of farmers reported that they do not purchase guinea pigs from IVITA anymore, because they are highly susceptibility to lymphadenitis, which is a highly contagious disease and causes swollen lymph nodes and affects the meat quality. Most of the respondents classified the "cuy RG" and "cuy G" as suitable for meat production and were satisfied with the performance of the animals. Therefore, 58.80% of respondents already recommended "cuy RG" to other farmers. However, 17.70% of the respondents would not recommend these animals because they are susceptible to disease, especially lymphadenitis. Therefore, IVITA should engage in more structured dialogue with farmers and regularly include their opinion in future improvement of its breeding strategies. This could help to reach higher acceptance rates by farmers.


Assuntos
Meio Ambiente , Fazendeiros , Animais , Cobaias , Humanos , Peru , Inquéritos e Questionários , Reprodução
3.
Water Sci Technol ; 80(4): 675-684, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31661447

RESUMO

Microbial processes are critical to the function of freshwater ecosystems, yet we still do not fully understand the factors that shape freshwater microbial communities. Furthermore, freshwater ecosystems are particularly susceptible to effects of environmental change, including influx of exogenous nutrients such as nitrogen and phosphorus. To evaluate the impact of nitrogen loading on the microbial community structure of shallow freshwater lakes, water samples collected from Lake Shenandoah (Virginia, USA) were incubated with two concentrations of either ammonium, nitrate, or urea as a nitrogen source. The potential impact of these nitrogen compounds on the bacterial community structure was assessed via 16S rRNA amplicon sequencing. At the phylum level, the dominant taxa in Lake Shenandoah were comprised of Actinobacteria and Proteobacteria, which were not affected by exposure to the various nitrogen treatments. Overall, there was not a significant shift in the diversity of the bacterial community of Lake Shenandoah with the addition of nitrogen sources, indicating this shallow system may be constrained by other environmental factors.


Assuntos
Lagos , Nitrogênio , Bactérias , Proteobactérias , RNA Ribossômico 16S
4.
Iran J Vet Res ; 20(2): 96-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531031

RESUMO

BACKGROUND: One of the factors limiting successful processing of alpaca (Vicugna pacos) semen is the viscosity of seminal plasma. The viscous nature of the collected ejaculate has hindered sperm cryopreservation as well as artificial insemination (AI) under field conditions. AIMS: The objective of this investigation was to evaluate recovery, motility, and plasma membrane integrity of alpaca spermatozoa after centrifugation in one of two different solutions at one of three different combinations of speed and time. METHODS: A total of 24 ejaculates was recovered from seven reproductively sound Huacaya males using a modified artificial vagina (AV) after training the animals for semen collection. A 2 × 3 factorial treatment arrangement was utilized for this study. Ejaculates were divided into fractions for centrifugation in one of two solutions (Tris extender or PureSperm®80 density gradient solution) at one of three combinations of speed and time (492 × g for 15 min, 1968 × g for 10 min, or 4448 × g for 7 min). The experiment was replicated eight times. RESULTS: Analysis revealed that centrifugation at 4448 × g for 7 min in PureSperm®80 provided a high recovery rate of spermatozoa with the highest sperm motility and functional integrity of plasma membrane post-centrifugation. Conclusion: Results suggest that adoption of this procedure (centrifugation at 4448 × g for 7 min in PureSperm®80) in the initial processing of alpaca ejaculates may enhance subsequent ability to use semen for AI and other assisted reproductive biotechnologies in this species.

5.
Proc AMIA Symp ; : 694-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11079973

RESUMO

This presentation features linguistic and terminology management issues related to the development of the Spanish version of the Systematized Nomenclature of Medicine (SNOMED). It aims at describing the aspects of translating and the difficulties encountered in delivering a natural and consistent medical nomenclature. Bunge's three-layered model is referenced to analyze the sequence of symbolic concept representations. It further explains how a communicative translation based on a concept-to-concept approach was used to achieve the highest level of flawlessness and naturalness for the Spanish rendition of SNOMED. Translation procedures and techniques are described and exemplified. Both the computer-aided and human translation methods are portrayed. The scientific and translation team tasks are detailed, with focus on Newmark's four-level principle for the translation process, extended with a fifth further level relevant to the ontology to control the consistency of the typology of concepts. Finally the convenience for a common methodology to develop non-English versions of SNOMED is suggested.


Assuntos
Idioma , Tradução , Vocabulário Controlado , Linguística
6.
J Fluoresc ; 5(4): 377-81, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24226914

RESUMO

The extent to which energy transfer occurs in electronically excited organic adlayer films on dielectric surfaces is investigated. Migration and subsequent trapping of the energy in the film are observed by pumping the singlet state of an organic adlayer of benzophenone and by monitoring the phosphorescence and fluorescence lifetimes. To observe the effects of adsorption, benzophenone was chosen as the adlayer because the energies of its well characterizedn,π carbonyl states are remarkably sensitive to solvent interactions. Upon excitation with a nitrogen laser, the perturbation on the electronic states of benzophenone by the substrate caused the emergence of the normally absent fluorescence from the adlayer traps at the interface between the surface of the dielectric substrate and the adlayer. Energy transfer to this interface was observed as a function of film thickness. On the surface of a single crystal of an organic crystal, naphthalene, energy transfer from the adlayer to the substrate was observed, whereas such transfer was not energetically possible with the other dielectric surfaces.

7.
Science ; 261(5128): 1564-7, 1993 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-17798115

RESUMO

The buried Chicxulub impact structure in Mexico, which is linked to the Cretaceous- Tertiary (K-T) boundary layer, may be significantly larger than previously suspected. Reprocessed gravity data over Northern Yucatan reveal three major rings and parts of a fourth ring, spaced similarly to those observed at multiring impact basins on other planets. The outer ring, probably corresponding to the basin's topographic rim, is almost 300 kilometers in diameter, indicating that Chicxulub may be one of the largest impact structures produced in the inner solar system since the period of early bombardment ended nearly 4 billion years ago.

8.
Chest ; 95(1): 226-7, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2909339

RESUMO

A patient with serum monoclonal gammopathy, Bence-Jones proteinuria, and bone marrow plasmacytosis underwent fiberoptic bronchoscopic study for evaluation of interstitial lung disease. Bronchoalveolar lavage fluid contained 47 percent plasma cells, which were monoclonal by immunoperoxidase staining. This is the first time BAL plasmacytosis has been demonstrated in a patient with a plasma cell dyscrasia.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Paraproteinemias/patologia , Plasmócitos/patologia , Idoso , Medula Óssea , Broncoscopia , Humanos , Pulmão/diagnóstico por imagem , Pneumopatias/etiologia , Pneumopatias/patologia , Masculino , Paraproteinemias/complicações , Paraproteinemias/diagnóstico por imagem , Radiografia
10.
Clin Chem ; 33(4): 563-6, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3549059

RESUMO

We analyzed the carcinoembryonic antigen (CEA) test results reported in the College of American Pathologists' (CAP) surveys to determine the relationship between the source of CEA used to manufacture the survey specimens and the discrepancies among analytical methods. With the 1983 survey specimens, which were prepared from metastatic colon carcinoma, laboratories using Roche RIA with Clinetics columns reported results that were only one-half the values reported by laboratories using the Abbott polyclonal enzyme immunoassay. With the 1984 specimens, prepared from a different metastatic colon carcinoma, and the 1985 specimens, prepared from a tissue-culture source of CEA, the Roche results were about one-sixth as large as the Abbott results. These differences are larger than the reported assay differences for patients' specimens. In addition, twofold proportional differences were found when survey and control specimens were tested with different lots of Abbott polyclonal reagent, whereas only random differences were found with 102 patients' specimens. Evidently, assay systems perform differently with proficiency-testing and control specimens than with patients' specimens.


Assuntos
Antígeno Carcinoembrionário/análise , Neoplasias do Colo/análise , Humanos , Técnicas Imunoenzimáticas , Controle de Qualidade , Padrões de Referência
11.
Life Sci ; 39(22): 2067-72, 1986 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3784770

RESUMO

Male, adult mice of the Binghamton heterogeneous stock received one of two doses of ethanol (1.0 g/kg or 2.0 g/kg in saline) alone or in combination with the calcium (Ca2+) slow channel blocker, verapamil (5.45 mg/kg in 25% v/v ethanol in saline). Hypothermic responses and motor incoordination were assessed in terms of rectal temperatures and rotorod activity both 20 and 60 min after drug administration. Verapamil alone did not affect body temperature, but it potentiated ethanol-induced hypothermia at both post-administration test times. Both verapamil and ethanol impaired muscular coordination and these effects were additive at the two observation periods. Verapamil did not affect ethanol blood levels from 10 to 80 min after administration of the drugs. Since motor impairment was observed when verapamil was administered with only its ethanol vehicle, this suggests a powerful interactive effect between the two drugs.


Assuntos
Temperatura Corporal/efeitos dos fármacos , Etanol/farmacologia , Destreza Motora/efeitos dos fármacos , Verapamil/farmacologia , Animais , Sinergismo Farmacológico , Injeções Intraperitoneais , Masculino , Camundongos
13.
Clin Biochem ; 16(5): 296-8, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6360417

RESUMO

We report our extended clinical experience with the use of an immunochemical method for LD-1 assay in 260 unselected, consecutive patients admitted with the clinical suspicion of recent myocardial infarction (M.I.). We determined on every patient total creatine kinase (CK) and total lactate dehydrogenase (LD) enzyme activity, and performed electrophoresis for LD isoenzymes as well as the heart-specific band of creatine kinase (CK-MB). An immunochemical assay for the heart-specific isoenzyme of LD (LD-1) was also performed. The timing of the samples was determined by the clinicians according to routine clinical protocols in the coronary care units. The diagnosis was based on the usual combination of clinical, electrocardiographic (EKG) and laboratory findings, and was arrived at independently by the clinician. In this extended series, the overall efficiency of the immunochemical LD-1 assay for the proper classification of the patients according with the discharge diagnosis was 92%. For CK-MB it was 90%, for EKG 77% and for LD electrophoresis 76%. The immunochemical LD-1 assay required no special instruments or highly skilled technicians and is probably the method of choice for the stat evaluation of recent M.I.


Assuntos
L-Lactato Desidrogenase/sangue , Infarto do Miocárdio/diagnóstico , Adulto , Idoso , Creatina Quinase/sangue , Feminino , Humanos , Técnicas Imunológicas , Isoenzimas , L-Lactato Desidrogenase/imunologia , Masculino , Pessoa de Meia-Idade
16.
Am J Clin Pathol ; 78(4 Suppl): 621-5, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7137103

RESUMO

To determine whether or not laboratories participating in the ligand assay survey of the College of American Pathologists can measure cobalamin (vitamin B-12) in the presence of cobalamin analogues, either cobalamin or cobinamide (a model for the non-physiological analogues of cobalamin) was added to pooled human serum, and aliquots of the various samples were submitted to the participants. Nine hundred and nineteen results that represented 13 commercially available methods were analyzed. For a sample containing 412 pg/mL. of cobalamin, the mean interference produced by 400 pg/mL of cobinamide, expressed as the apparent increase in the cobalamin concentration, was 26.5 pg/mL with a range of 18 to 42 pg/mL. The mean recovery of added cobalamin was 104% of the expected value.


Assuntos
Ensaio Radioligante/métodos , Vitamina B 12/sangue , Humanos , Patologia Clínica/normas , Manejo de Espécimes
17.
Am J Clin Pathol ; 75(6): 786-93, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7258140

RESUMO

A ligand assay specific for cobalamin that uses mouse stomach as the source of intrinsic factor has been developed. When mouse stomach extract incubated with radiocobalamin is fractionated by gel chromatography, the radioactive complex elutes as a single peak with apparent molecular weight of 54,900. Formation of the complex is greater than 98% inhibited by human anti-intrinsic factor antibody. When the equivalent of 10,000 pg/ml of cobinamide is added to serum, the apparent cobalamin concentration detected averages 8.5 pg/ml. Correlation with the Lactobacillus leichmannii microbiologic assay results in the regression equation y = 0.97x + 20. In six patients who had megaloblastic anemia the serum cobalamin by the mouse intrinsic factor ligand assay ranged from 0 to 9 pg/ml. Because the primary source of intrinsic factor is free of R proteins, there is no need for extensive purification of the extract. The assay is sensitive, precise, and accurate, and no more difficult to perform than other conventional ligand assay procedures.


Assuntos
Fator Intrínseco/análise , Ensaio Radioligante/métodos , Estômago/análise , Vitamina B 12/análise , Anemia Megaloblástica/sangue , Animais , Anticorpos/análise , Cromatografia em Gel , Humanos , Lactobacillus/análise , Camundongos , Ligação Proteica , Saliva/análise
18.
Am J Clin Pathol ; 75(5): 701-7, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7234756

RESUMO

An evaluation of a new immunochemical method for the heart isoenzyme of lactic dehydrogenase (LDH-1) is described. In this assay, a goat antibody against the M subunit of LDH is added to a patient's serum. Donkey antigoat gamma globulin is then added, which precipitates the M-anti-M complex. LDH activity in the supernatant is thus a measure of the heart isoenzyme, since this isoenzyme is not precipitable by the anti-M antibody. Assays for total CK, CK-MB, and total LDH, and LDH electrophoresis were performed along with an immunochemical LDH-1 assay on 261 serum samples from 49 patients clinically suspected to have acute myocardial infarctions. These were performed on admission and 12, 24, 48, 72, and 96 hours later. The diagnosis of acute infarction was confirmed for 25 of the 49 patients and ruled out for 19. Five patients were classified clinically as borderline cases for the diagnosis of acute myocardial infarction. All 25 patients with the clinical diagnosis of myocardial infarction had positive results by both electrophoresis and immunochemistry; four of the five borderline patients had positive results by electrophoresis. All five borderline patients had positive results by immunochemistry. None of the 19 patients without apparent myocardial injury had positive results by either electrophoresis or immunochemistry. Ten (40%) of the 25 samples collected at the time of admission from 25 patients who had myocardial infarctions had elevated LDH-1 activity by electrophoresis, while 14 patients (56%) had increased LDH-1 by immunochemistry. The immunochemical method for LDH-1 is more sensitive than electrophoresis for the detection of myocardial infarction and offers the further advantages of greater simplicity, precision, and accuracy, while being no less specific.


Assuntos
Imunoensaio , L-Lactato Desidrogenase/sangue , Eletroforese , Humanos , Infarto do Miocárdio/diagnóstico
19.
J Anal Toxicol ; 4(6): 272-4, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6782370

RESUMO

We described a simple procedure for the flash heater methylation of valproic acid and cyclohexylacetic acid (internal standard) by gas-liquid chromatography (GLC). A small volume (100 microL) of sample is acidified with 10% perchloric acid and extracted into hexane. An aliquot is back extracted into 5% tetramethylammonium hydroxide (TMH). A 1 microL sample of the TMH layer is injected into the GLC equipped with flame ionization detector (FID) and a 6 ft x 2 mm i.d. - nickel column packed with 3% OV-17 on 80/100 mesh Supelcoport. The injector temperature is set at 350 degrees C to ensure methylation. Recoveries are greater than 95% of theoretical value. The linearity for calibration points between 15 and 180 microgram/mL is excellent (coefficient of correlation and determination greater than 0.9999). The procedure is rapid and sensitive and does not require a dedicated column in the gas chromatograph.


Assuntos
Ácido Valproico/análise , Cromatografia Gasosa/métodos , Metilação , Microquímica
20.
Am J Clin Pathol ; 72(5): 852-5, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-506997

RESUMO

A new colorimetric assay for the determination of serum free hemoglobin utilizing the noncarcinogenic compound leucomalachite green is described. The reaction is complete in 8 min, with the resulting color stable for at least 30 min. The absorption maximum for the leucomalachite green reaction product was observed at 617 nm. Precision studies at 50 and 300 mg/l free hemoglobin concentrations resulted in within-run variations of 1.9 and 1.7%, while the day-to-day variations were 6.9 and 4.0%, respectively. Accuracy studies at concentrations of 50, 150 and 300 mg/l resulted in recoveries of 88, 95 and 98% of theoretical values.


Assuntos
Compostos de Anilina , Compostos de Benzilideno , Corantes , Hemoglobinas/análise , Heparina/farmacologia , Humanos , Plasma/análise , Corantes de Rosanilina , Espectrofotometria
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA