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1.
Appl Opt ; 62(34): 9089-9095, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108746

RESUMO

Aluminum thin films were deposited on a 3D prototype employing the direct current magnetron sputtering technique to fabricate a lightweight 3D first surface mirror. Before the aluminizing, the surface of the prototypes was evaluated with interferometry and atomic force microscope (AFM). The thin films were characterized using profilometry, UV-Vis spectroscopy, x-ray diffraction, AFM, x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. High adherence and homogeneous deposition of the aluminum's thin films were achieved. In addition, the purity of the material was confirmed by XPS analysis.

2.
Actas Dermosifiliogr ; 114(1): 39-48, 2023 Jan.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35905817

RESUMO

Numerous surgical and nonsurgical modalities are available to treat basal cell carcinoma (BCC), but their true effectiveness and safety is unknown. This article summarizes the evidence presented in a recent Cochrane review and aims to facilitate the interpretation of the review's findings for the Spanish and Latin American scientific communities. Much of the evidence the reviewers found came from single studies, preventing meta-analysis. Conventional surgical excision continues to be the most effective treatment for low-risk BCC. Most studies had small sample sizes, and some had problems with blinding, limitations which will have affected the assessment of subjective outcomes, such as pain and cosmetic results. The authors identified a lack of standardization in relation to recurrences and cosmetic outcomes that threatens not only the internal validity of the studies but also their external validity and reproducibility.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Humanos , Carcinoma Basocelular/cirurgia , Dor , Reprodutibilidade dos Testes , Neoplasias Cutâneas/cirurgia
3.
J Radiol Prot ; 42(3)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940166

RESUMO

The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for pediatric interventional cardiology (IC) procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study was conducted in the framework of the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the program was focused on pediatric IC. Dose data from diagnostic and therapeutic procedures were collected between December 2020 and December 2021. Regional DRLs were set as the third quartile of patient dose data (kerma area product) collected in 18 hospitals from 10 countries in an initial sample of 968 procedures. DRLs were set for four age bands and five weight ranges. The values obtained for the four age bands (<1 yr, 1 to <5 yr, 5 to <10 yr and 10 to <16 yr) were 2.9, 6.1, 8.8 and 14.4 Gy cm2for diagnostic procedures, and 4.0, 5.0, 10.0 and 38.1 Gy cm2for therapeutic procedures, respectively. The values obtained for the five weight bands (<5 kg, 5 to <15 kg, 15 to <30 kg, 30 to <50 kg and 50 to <80 kg) were 3.0, 4.5, 8.1, 9.2 and 26.8 Gy cm2for diagnostic procedures and 3.7, 4,3, 7.3, 16.1 and 53.4 Gy cm2for therapeutic procedures, respectively. While initial data were collected manually as patient dose management systems (DMSs) were not available in most of the hospitals involved in the program, a centralized automatic DMS for the collection and management of patient dose indicators has now been introduced and is envisaged to increase the sample size. The possibility of alerting on high dose values and introducing corrective actions will help in optimization.


Assuntos
Cardiologia , Níveis de Referência de Diagnóstico , Cardiologia/métodos , Criança , Fluoroscopia , Humanos , América Latina , Doses de Radiação , Radiografia Intervencionista/métodos , Radiologia Intervencionista , Valores de Referência
4.
Appl Opt ; 59(13): D104-D110, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400630

RESUMO

We report the application of cyclic voltammetry and absorption spectroscopy to the characterization and study of the stability of silver colloids in water. The samples are prepared via chemical reduction and the reactions are catalyzed by irradiation with white light. The electrochemical response is related to the characteristic sample surface plasmon resonance (SPR) in the UV-visible absorption spectra. Cyclic voltammetry shows a characteristic reduction peak whose position is specific to each analyzed sample. Optical analysis of a colloid precursor during a 12 h time span, under low-power white-light irradiation, shows that nanoparticles undergo change in size and surface state (absorption bands splitting and inversion) to attain the "stable" colloidal form. While the absorption spectrum bands of the precursor return almost periodically to similar positions, the cyclic voltammogram characteristic reduction peak is displaced as a function of time. Finally, we follow the SPR changes of one "stable" colloid being subjected to electrolysis, heating, and sunlight irradiation, for environmental remediation purposes. Sunlight exposure produces the most significant SPR intensity drop, but the electrochemical technique shows itself promising as well.

5.
Trop Anim Health Prod ; 52(5): 2761-2768, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32488696

RESUMO

Group A rotavirus (RVA) and bovine coronavirus (BCoV) are the two main viral enteropathogens associated with neonatal calf diarrhea. The aim of the present survey was to investigate the epidemiology and the role of RVA and BCoV in the presentation of dairy and beef calf diarrhea in Lerma Valley of Salta province, within the Northwest region of Argentina. Stool samples of calves with or without diarrhea younger than 2 months of age were collected from 19 dairy farms and 20 beef farms between the years 2014 and 2016. Stool samples were screened for RVA and BCoV detection by ELISA. Heminested multiplex RT-PCR was used for RVA typing and RT-PCR to confirm BCoV. Positive samples were submitted to sequencing analysis. Bovine RVA and BCoV were circulating in 63% (12/19) and 10.52% (2/19) of the dairy farms, respectively, where 9.5% (46/484) of the calves were positives to RVA and 0.4% (2/484) to BCoV. In beef herds, RVA was detected in 40% (8/20) of the farms and in 6.75% (21/311) of the calves, without positives cases of BCoV. Molecular analysis showed that in dairy farms, G6P[11] and G10P[11] were the prevalent RVA strains, while in beef farms, G10P[11] was the prevalent. The main finding was the detection for the first time of a G15P[11] causing diarrhea in beef calves of Argentina that represents a new alert to be consider for future vaccine updates. Analysis of detected BCoV showed that it is related to the other circulating strains of Argentina.


Assuntos
Doenças dos Bovinos/virologia , Coronavirus Bovino/isolamento & purificação , Diarreia/veterinária , Infecções por Rotavirus/veterinária , Rotavirus/isolamento & purificação , Animais , Animais Recém-Nascidos , Argentina , Bovinos , Coronavirus Bovino/genética , Diarreia/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/virologia , Genótipo , Rotavirus/genética , Infecções por Rotavirus/virologia
6.
Br J Dermatol ; 181(4): 770-777, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30729508

RESUMO

BACKGROUND: In recent years, the need for international, objective, patient-reported outcomes measures has grown as international collaboration has increased. As most quality-of-life scales have been developed in English, there is a growing need to adapt them transculturally to obtain equivalence between the original instrument and the adapted scale. OBJECTIVES: To assess the construct and convergent-discriminant validity and responsiveness of the Colombian version of Skindex-29. METHODS: The cross-sectional and longitudinal validity and responsiveness were tested in both healthy and dermatology patients. Construct validity was tested through a confirmatory factor analysis. The convergent-discriminant validity was assessed by examining the Spearman correlation coefficient. Change sensitivity was tested by means of the standardized response mean. The effect size and the minimum detectable change were also assessed. RESULTS: A total of 265 participants were included; 21·1% were healthy individuals, and 78·9% patients had either inflammatory or noninflammatory skin diseases. Confirmatory factor analysis showed an adequate comparative fit index and Tucker-Lewis index adjustment for the root mean square error of approximation. Convergent validity showed moderate correlations between the emotions, functioning and physical function or physical role domains. Discriminant validity showed low correlations between overall domains for both scales. Sensitivity to change at the first and third month showed effect sizes in global Skindex scores of 0·92 and 0·82, respectively. CONCLUSIONS: The Colombian version of Skindex-29 is a valid and clinically sensitive instrument, which can be used for clinical practice and for research to measure the impact of skin diseases on the quality of life of dermatology patients.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Dermatopatias/diagnóstico , Adolescente , Adulto , Idoso , Colômbia , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psicometria/métodos , Reprodutibilidade dos Testes , Dermatopatias/psicologia , Traduções , Adulto Jovem
7.
Radiologia ; 59(4): 313-320, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28473218

RESUMO

OBJECTIVE: To evaluate the diagnostic performance of the length of the tumor contact with the capsule (LTC) and the apparent diffusion coefficient (ADC) map in the prediction of microscopic extracapsular extension in patients with prostate cancer who are candidates for radical prostatectomy. MATERIAL AND METHODS: We used receiver operating curves to retrospectively study the diagnostic performance of the ADC map and the LTC as predictors of microscopic extracapsular extension in 92 patients with prostate cancer and moderate to high risk who were examined between May 2011 and December 2013. RESULTS: The optimal cutoff for the ADC map was 0.87× 10-3 mm2/s, which yielded an area under the ROC curve of 72% (95% CI: 57%-86%), corresponding to a sensitivity of 83% and a specificity of 61%. The optimal cutoff for the LTC was 17.5mm, which yielded an area under the ROC curve of 74% (95% CI: 61%-87%), corresponding to a sensitivity of 91% and a specificity of 57%. Combining the two criteria improved the diagnostic performance, yielding an area under the ROC curve of 77% (95% CI: 62%-92%), corresponding to a sensitivity of 77% and a specificity of 61%. We elaborated a logistic regression model, obtaining an area under the ROC curve of 82% (95% CI: 73%-93%). CONCLUSIONS: Using quantitative measures improves the diagnostic accuracy of multiparametric magnetic resonance imaging in the staging of prostate cancer. The values of the ADC and LTC were predictors of microscopic extracapsular extension, and the best results were obtained when both values were used in combination.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Estudos Retrospectivos
8.
Parasitol Int ; 100: 102869, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38395104

RESUMO

The objective of this work was to describe the dynamics of development and survival of the free-living stages of cattle gastrointestinal nematodes (GIN) in fecal matter (FM) and pasture during the dry season in the Lerma Valley, Salta province, northwestern Argentina (NWA) to contribute to GIN management. The climate in the region is characterized by a rainy summer followed by a dry season from middle autumn to early spring. Fecal matter from calves naturally infected with GIN was deposited on three experimental field plots in April, July and October 2019, corresponding to the beginning, middle and end of the dry season, respectively. Each experimental unit consisted of 7 stools of about 800 g and had four repetitions. To determine the development from egg to infective larvae (L3), the first sampling (5 g fecal matter) was performed from the 10th day post-contamination and continued every 3 days until L3 were found. Subsequently, a monthly sampling was made until two consecutive negative results were obtained. Sampling of pasture began three days after the L3 recovery from FM, and continued monthly until two negative results were obtained. The following parameters were evaluated: development time and development rate from egg to L3; permanence time of L3 in feces; time of appearance on pasture; migration rate; and permanence time of L3 on pasture. The main genera of parasites present were Cooperia and Haemonchus. Significant differences were observed in the development time among contamination months (p < 0.001); development time was highest in the July contamination (28 days), with October and April contamination averaging 9 and 10 days, respectively. Development time also showed significant differences (p < 0.01) among contamination months, being highest in October (31.48%). The highest permanence time in fecal matter values were recorded in the July contamination (183 days) and migration rate was highest in the October contamination (42.49%). The highest time of appearance on pasture value was recorded in the July contamination (117 days). Finally, the highest permanence time of L3 in feces values were detected in the October contamination (148 days). The results of this work show that fecal contamination in the NWA region in the dry season would play an epidemiological role in the GIN cycle as a source of infection for the next productive cycle in the rainy season.


Assuntos
Doenças dos Bovinos , Haemonchus , Nematoides , Infecções por Nematoides , Animais , Bovinos , Estações do Ano , Argentina/epidemiologia , Meio Ambiente , Fezes/parasitologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Larva , Contagem de Ovos de Parasitas/veterinária , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia
9.
Food Res Int ; 174(Pt 1): 113568, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986441

RESUMO

Salmonella spp. can be present in pasteurized liquid egg products because of its heat resistance or post-processing contamination, thereby representing a food safety risk. The effect of 1000 IU nisin/ml plus 20 mM disodium ethylenediaminetetraacetic acid (EDTA), two refrigerated temperatures (7 °C and 10 °C), and two inoculation levels (103 and 105 cfu/ml) were studied in the growth of S. Typhimurium in pasteurized liquid whole egg (LWE). Two mathematical models were used to fit the microbial curves. Physicochemical characteristics of LWE, such as pH and color, were assessed for 31 days at the two storage temperatures, and no significant changes (p < 0.05) were observed for most of the samples. Results showed the significant impact of temperature on microbial growth. Samples kept at 7 °C showed the decay of microbial cells during storage; meanwhile, the effect at 10 °C was shown as fast growth. The combination of nisin plus EDTA and 7 °C accelerated the decay of microbial cells during the storage showing a synergistic effect. The Weibull model described the decline of cells during the shelf-life. Meanwhile, the logistic model fitted the growth of Salmonella in LWE at 10 °C. Adding these additives to LWE, combined with the correct temperature during pasteurization and adequate conditions during the cold chain, can minimize the food safety risk related to Salmonella.


Assuntos
Nisina , Salmonella typhimurium , Temperatura , Nisina/farmacologia , Ácido Edético , Contagem de Colônia Microbiana
10.
Food Sci Technol Int ; 17(6): 541-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22049160

RESUMO

High hydrostatic pressure (HHP) was applied to fresh mango nectar (FMN) and sterilized mango nectar (SMN) to inactivate Escherichia coli and pectin methylesterase (PME). Pressure was applied at 275, 345 and 414 MPa. The come-up time (CUT) as well as 1, 2 and 4 min of treatment times were applied at the selected pressure to evaluate the inactivation effect on E. coli and PME. Total plate counts (TPC) were also evaluated in FMN. Results showed that mesophiles are inactivated in FMN to an important degree (up to 4 log) only with the CUT; the highest inactivation for mesophiles (7 log) was reported at 414 MPa after 4 min. Meanwhile, for E. coli 345 and 414 MPa after 2 and 1 min, respectively, were able to inactivate all viable cells in FMN. However, in SMN after 4 min at 275 MPa all cells of E. coli were also inactivated, showing the protective effect of the media between FMN and SMN. The PME showed its resistance to be inactivated with high pressure, showing the highest decrease in enzymatic activity (45%) after 4 min at 345 MPa but with an important activation at the highest pressure (414 MPa).


Assuntos
Bebidas/microbiologia , Hidrolases de Éster Carboxílico/metabolismo , Escherichia coli/isolamento & purificação , Conservação de Alimentos , Frutas/microbiologia , Mangifera/microbiologia , Proteínas de Plantas/metabolismo , Contagem de Colônia Microbiana , Ativação Enzimática , Escherichia coli/crescimento & desenvolvimento , Doenças Transmitidas por Alimentos/prevenção & controle , Frutas/enzimologia , Temperatura Alta , Pressão Hidrostática , Cinética , Mangifera/enzimologia , Viabilidade Microbiana , Desnaturação Proteica , Esterilização , Fatores de Tempo
11.
Vet Parasitol Reg Stud Reports ; 21: 100429, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862909

RESUMO

Coccidiosis of sheep is an intestinal infection caused by protozoa of the genus Eimeria. An outbreak of the disease in adult sheep from Salta province, northwestern Argentina, was studied to establish its clinical, epidemiological, pathological and etiological aspects. The affected animals were part of a flock of 20 sheep brought from Formosa province about 10 days before. Most sheep (80% incidence) showed hemorrhagic diarrhea, dehydration and loss of body condition; six of them died and two that became permanently recumbent were euthanized. Three necropsied sheep showed mild mesenteric lymphadenomegaly, diffuse proliferative enteritis in the small and large intestines, and mucosal thickening. Histopathological studies exhibited diffuse proliferative enteritis and presence of structures compatible with intracellular coccidia at different stages of development. Parasitological studies (n = 12) resulted in an average of 16,636.6 (± 15,266.8) Eimeria oocysts per gram of feces (range 1680-46,400). Taxonomy of Eimeria species based on analysis of sporulated oocysts derived from 4 fecal samples (n = 100 oocyst per sample) showed, on average, a high prevalence of E. ovinoidalis (61.5%), followed by E. parva (27.2%), and lower proportions of E. crandallis (5.3%), E. ahsata (3.2%) and E. intricata (2.8%). Clinical and pathological findings confirmed the diagnosis of coccidiosis in the affected sheep; parasitological results showed that E. ovinoidalis was the main species responsible for the clinical signs. Clinical coccidiosis is considered unusual in adult sheep, but the present case shows that under favorable environmental and/or management conditions, this infection may be highly deleterious for adult sheep.


Assuntos
Coccidiose/veterinária , Surtos de Doenças/veterinária , Eimeria/isolamento & purificação , Doenças dos Ovinos/patologia , Animais , Argentina/epidemiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/patologia , Eimeria/classificação , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
12.
Vet Parasitol ; 162(3-4): 338-41, 2009 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-19349120

RESUMO

Faecal samples from mostly adult llamas (n=626), vicuñas (n=161) and guanacos (n=4) were obtained between December 2004 and July 2008 in three Provinces of Northwest Argentina in order to study the prevalence of Eimeria macusaniensis and Eimeria ivitaensis. Faeces were examined by a flotation technique using a Cl(2)Zn+ClNa solution (specific gravity=1.59). Oocysts of E. macusaniensis occurred in 88.3% of 77 llama herds and in 50.3% of 626 llamas sampled whereas oocysts of E. ivitaensis occurred in only four llamas (herd and llama prevalence of 5.2% and 0.6%, respectively). The individual prevalence of E. macusaniensis in vicuñas and guanacos were of 14.3% and 25.0%, respectively. E. ivitaensis was not detected in these latter species. The results showed a prevalence of E. macusaniensis higher than previously reported in adult domestic camelids (llamas and alpacas). In contrast, the very low prevalence of E. ivitaensis in llamas and its absence in wild camelids (vicuñas and guanacos) was remarkable. Differences between prevalence of both coccidian species are discussed.


Assuntos
Camelídeos Americanos , Coccidiose/veterinária , Eimeria/isolamento & purificação , Animais , Argentina/epidemiologia , Coccidiose/classificação , Coccidiose/epidemiologia , Fezes/parasitologia , Prevalência
13.
Rev Argent Microbiol ; 41(4): 212-4, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-20085183

RESUMO

Mycoplasma ovis is an obligatory parasite of the erythrocytes from small ruminants (sheep, goat), wherein it causes chronic or acute anaemia. This agent shows worldwide distribution. However, its dispersion is still unknown in Argentina. This work describes an outbreak of mycoplasmosis occurred in January 2007 in a sheep flock from Rosario de la Frontera, Salta, Argentina. Adult sheep became ill with a mortality rate of 17.8%. All blood smears (n = 11) examined by Giemsa stain showed the presence of small basophile bodies characteristic of M. ovis infection, indicating a high prevalence of the infection in the flock. The molecular diagnosis (n = 9) confirmed the findings through the amplification of two fragments from the 16S rRNA gene. This is the third report of M. ovis in Argentina and the first one concomitant with clinical signs at flock level.


Assuntos
Surtos de Doenças/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Doenças dos Ovinos/epidemiologia , Animais , Argentina/epidemiologia , Eritrócitos/microbiologia , Mycoplasma/classificação , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/microbiologia , Filogenia , Reação em Cadeia da Polimerase , Ribotipagem , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
14.
Rev Esp Anestesiol Reanim (Engl Ed) ; 66(2): 72-77, 2019 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30424890

RESUMO

BACKGROUND AND OBJECTIVES: Practice guidelines for preoperative fasting have not clearly established the fasting time needed after oral administration of water-soluble contrast media. The aim of this study was to determine the time required for the gastric emptying during the water-soluble contrast media in patients with acute abdominal pain. METHODS: This prospective longitudinal study included sixty-eight patients older than 18 years of age with acute abdominal pain, who required a water-soluble contrast media enhanced abdominal computed tomography study. Plain radiographs were obtained hourly until complete the gastric emptying. Patients with probable bowel obstruction were not included in the study. RESULTS: A total of 31 (45,6%), 54 (79,4%), and 64 (94,1%) patients achieved a complete gastric clearance of barium in 1, 2 and 3 hours, respectively. All patients achieved complete emptying of water-soluble contrast media within 6 hours. Gastric emptying time was not associated with gender (P=0,44), body mass index (P=.35), fasting time prior to water-soluble contrast media intake (P=0,12), administration of opioids in the emergency room (P=0,7), and the presence of comorbidities (P=0,36). CONCLUSION: Ninety-four percent of the patients with acute abdominal pain achieved complete gastric emptying within 3hours after the administration of water-soluble contrast media. All of them achieved complete gastric emptying within 6hours. The results suggested 6hours after oral intake of the contrast media is enough to complete transit of water-soluble contrast media through the stomach and avoid unnecessary risks.


Assuntos
Abdome Agudo/diagnóstico por imagem , Sulfato de Bário/farmacocinética , Meios de Contraste/farmacocinética , Jejum , Esvaziamento Gástrico , Tomografia Computadorizada por Raios X/métodos , Abdome Agudo/fisiopatologia , Adulto , Sulfato de Bário/administração & dosagem , Diatrizoato/administração & dosagem , Diatrizoato de Meglumina/administração & dosagem , Feminino , Humanos , Estudos Longitudinais , Masculino , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Fatores Sexuais , Solubilidade , Fatores de Tempo
15.
Sci Rep ; 9(1): 10062, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296894

RESUMO

One of the major consequences of the lack of a functional VHL protein in von Hippel-Lindau disease, a rare cancer, is the constitutive activation of the HIF pathway. This activation ends up in the generation of Central Nervous System (CNS) Hemangioblastomas among other tumours along the lifespan of the patient. Nowadays, only surgery has been proven efficient as therapy since the systemic attempts have failed. Propranolol, a non-specific ß1-and ß2-adrenergic receptor antagonist, was recently designated as the first therapeutic (orphan) drug for VHL disease. Nevertheless, its ß1 affinity provokes the decrease in blood pressure, being not recommended for low or regular blood pressure VHL patients. In order to overcome the ß1-drawback, the properties of a high specific ß2-adrenergic receptor blocker named ICI-118,551 have been studied. ICI-118,551 was able to decrease Hemangioblastomas cell viability in a specific manner, by triggering apoptosis. Moreover, ICI-118,551 also impaired the nuclear internalization of HIF-1α in Hemangioblastomas and hypoxic primary endothelial cells, reducing significantly the activation of HIF-target genes and halting the tumour-related angiogenic processes. In this work, we demonstrate the therapeutical properties of ICI-118,551 in VHL-derived CNS-Hemangioblastoma primary cultures, becoming a promising drug for VHL disease and other HIF-related diseases.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Núcleo Celular/metabolismo , Neoplasias do Sistema Nervoso Central/metabolismo , Hemangioblastoma/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Propanolaminas/farmacologia , Doença de von Hippel-Lindau/metabolismo , Apoptose , Neoplasias do Sistema Nervoso Central/complicações , Hemangioblastoma/complicações , Humanos , Terapia de Alvo Molecular , Mutação/genética , Neovascularização Patológica , Transdução de Sinais , Células Tumorais Cultivadas , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/complicações
16.
Cytogenet Genome Res ; 121(3-4): 211-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18758161

RESUMO

Intracranial germ cell tumors (ICGCTs) occur mainly in male children and adolescents. Polyploidy of the X chromosome and X hypomethylation have been suggested as mechanisms of malignant transformation independently of the histological tumor type. On the other hand, several reports associate these tumors with Klinefelter's syndrome (KS). Recent reports indicate that KS patients have an increased relative risk for development of malignant mediastinal germ cell tumors and also around 8% of male patients with primary mediastinal tumors have KS. In an attempt to explore the frequency of KS amongst patients with ICGCTs and to confirm the presence of X chromosome polyploidies in these tumors, we studied 13 young male patients with ICGCTs. Paraffin-embedded tumoral and normal tissues were studied by FISH. KS was found in 15% of the cases, demonstrating that this constitutive aneuploidy may be related to carcinogenesis. When tumor and non-tumor tissues were compared, statistically significant X and Y chromosome polyploidies in tumors were revealed. These results emphasize that aneuploidies are involved in ICGCT tumorigenesis.


Assuntos
Aneuploidia , Neoplasias Encefálicas/genética , Síndrome de Klinefelter/genética , Neoplasias Embrionárias de Células Germinativas/genética , Cromossomos Sexuais , Adolescente , Neoplasias Encefálicas/complicações , Criança , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Síndrome de Klinefelter/complicações , Neoplasias Embrionárias de Células Germinativas/complicações
17.
Biochim Biophys Acta ; 1425(1): 189-203, 1998 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-9813320

RESUMO

Many of the cytopathic effects of nitric oxide (NO*) are mediated by peroxynitrite (PN), a product of the reaction between NO* and superoxide radical (O2*-). In the present study, we investigated the role of PN, O2*- and hydroxyl radical (OH*) as mediators of epithelial hyperpermeability induced by the NO* donor, S-nitroso-N-acetylpenicillamine (SNAP), and the PN generator, 3-morpholinosydnonimine (SIN-1). Caco-2BBe enterocytic monolayers were grown on permeable supports in bicameral chambers. Epithelial permeability, measured as the apical-to-basolateral flux of fluorescein disulfonic acid, increased after 24 h of incubation with 5.0 mM SNAP or SIN-1. Addition of 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, an NO* scavenger, or Tiron, an O2*- scavenger, reduced the increase in permeability induced by both donor compounds. The SNAP-induced increase in permeability was prevented by allopurinol, an inhibitor of xanthine oxidase (a source of endogenous O2*-). Diethyldithiocarbamate, a superoxide dismutase inhibitor, and pyrogallol, an O2* generator, potentiated the increase in permeability induced by SNAP. Addition of the PN scavengers deferoxamine, urate, or glutathione, or the OH* scavenger mannitol, attenuated the increase in permeability induced by both SNAP and SIN-1. Both donor compounds decreased intracellular levels of glutathione and protein-bound sulfhydryl groups, suggesting the generation of a potent oxidant. These results support a role for PN, and possibly OH*, in the pathogenesis of NO* donor-induced intestinal epithelial hyperpermeability.


Assuntos
Absorção Intestinal/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Antioxidantes/farmacologia , Células CACO-2 , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Humanos , Radical Hidroxila/farmacologia , Absorção Intestinal/fisiologia , Intestinos/efeitos dos fármacos , Intestinos/fisiologia , Cinética , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Nitratos/farmacologia , Óxido Nítrico/fisiologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Permeabilidade/efeitos dos fármacos , Superóxido Dismutase/farmacologia , Superóxidos/farmacologia
18.
Vet Parasitol ; 134(3-4): 267-72, 2005 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-16143451

RESUMO

Biological data of immature stages of Amblyomma tigrinum were obtained from larvae and nymphs both fed on rats and rabbits. Data from nymphs recovered from a wild rodent (Galea musteloides) are also reported. Additional results in DNA composition of males moulted from nymphs fed on laboratory and wild hosts are presented. The ticks were maintained in darkness at 27 +/- 1 degrees C and 83-86% RH. The mean recovery rates were 49.1% and 43.6% with a moulting success of 96.2% and 90.8% in larvae fed on rats and rabbits, respectively. The engorgement weights were almost identical in larvae recovered from both hosts. The mean recovery rates of nymphs were 37.3% and 69.9% in specimens fed on rats and rabbits, respectively. The moulting success was 94.5%, 100% and 98.1% in nymphs fed on rats, rabbits and G. musteloides, respectively. Nymphs from all hosts moulting to females were significantly heavier (P < 0.01) than those moulting to males despite their range of engorgement weight showed overlap. A higher proportion (>or=61.5%) of nymphs from all hosts moulted to females. Present results suggest that members of Rodentia and Lagomorpha are suitable hosts for the immature stages of A. tigrinum, contrasting with previous results from Brazilian colonies of this tick. The DNA sequence from ticks fed on G. musteloides showed 99.7% identity with that from ticks fed on rabbits and also with the DNA sequence already available (GenBank AY498562 ) for A. tigrinum.


Assuntos
Ixodidae/fisiologia , Animais , DNA Mitocondrial/química , DNA Mitocondrial/genética , Feminino , Ixodidae/genética , Ixodidae/crescimento & desenvolvimento , Masculino , Muda/fisiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Coelhos , Ratos , Ratos Wistar , Alinhamento de Sequência , Análise de Sequência de DNA
19.
Vet Parasitol ; 127(2): 157-63, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15631909

RESUMO

The efficacy of a commercial pour-on formulation of eprinomectin, a macrocyclic lactone, against experimental infestations of Boophilus microplus (Canestrini) ticks was evaluated in two trials involving 27 Bos taurus calves. The first trial was designed to evaluate the effects of a single treatment at a dose of 0.5 mg/kg of body weight against standard size B. microplus females (4.5-8.0 mm long). A significant reduction in tick numbers (P<0.05, Wilcoxon test) was observed between treated calves as compared to untreated ones from Day 3 (44% efficacy) after treatment to the end of the trial on Day 28 (96.9%), with a peak efficacy of 97.1% on Day 21. In the second trial the effect of eprinomectin on standard size tick numbers, engorgement weight and fertility of female ticks from calves with a single treatment dose of 1 mg/kg on Day 0 and calves treated twice at a dose of 0.5 mg/kg on Days 0 and 4 was evaluated. An efficacy >93% was obtained from Day 2 to Day 28 after treatment in calves treated twice at 0.5 mg/kg, and to the end of the trial (Day 35) in calves treated once with 1 mg/kg. The 1mg/kg treatment provided >98% residual efficacy for at least 7 days. During the first part of the second trial the efficacy of eprinomectin resulted from a dramatic adverse effect on engorgement weight and fertility of female ticks, with 100% control on Day 5 (dosage of 1 mg/kg) and on Days 6 and 7 (two doses of 0.5 mg/kg). Following Day 7, most of the effect was due to reduction in the number of standard size female ticks.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Inseticidas/administração & dosagem , Ivermectina/análogos & derivados , Ivermectina/administração & dosagem , Ixodidae/efeitos dos fármacos , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/veterinária , Administração Tópica , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Relação Dose-Resposta a Droga , Feminino , Ixodidae/crescimento & desenvolvimento , Ixodidae/fisiologia , Reprodução/efeitos dos fármacos , Infestações por Carrapato/tratamento farmacológico , Resultado do Tratamento
20.
Radiat Prot Dosimetry ; 165(1-4): 250-3, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25843951

RESUMO

The aim of this work was to analyse the radiation dose for patients and staff between X-ray systems, a new biplane with flat-panel detectors (FDs) and a conventional system equipped with image intensifier (II). Entrance surface air kerma (ESAK) and scatter doses were measured on polymethyl methacrylate (PMMA) phantoms of different thicknesses (from 4 to 16 cm). The ESAK values for the different acquisition modes and PMMA thicknesses were higher for the II in comparison with FDs. For the II, the scatter dose rates ranged from 0.67 to 12.2 mSv h(-1) at the eye position of the cardiologist during fluoroscopy and cine modes. At the lower extremities, these values were 1.11 and 24.24 mSv h(-1). In the case of the FDs, these values ranged from 0.24 to 0.67 mSv h(-1) for eye lens and from 0.73 to 2.01 mSv h(-1) for the position of cardiologist's ankle. The newly installed X-ray system showed an average reduction factor of up to 9.7 times for ESAK values. For the staff with an average reduction factor of 15.9 times at the eye position during fluoroscopy and cine modes, no protective tools are used. At the lower extremities, this value was 7.6 times.


Assuntos
Angiografia/instrumentação , Cardiologia/instrumentação , Radiologia Intervencionista/instrumentação , Ar , Angiografia/métodos , Cardiologia/métodos , Desenho de Equipamento , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Humanos , Pediatria/instrumentação , Pediatria/métodos , Imagens de Fantasmas , Polimetil Metacrilato/química , Doses de Radiação , Proteção Radiológica/métodos , Intensificação de Imagem Radiográfica/instrumentação , Radiologia Intervencionista/métodos , Espalhamento de Radiação , Raios X
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