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1.
Phys Rev Lett ; 132(15): 152503, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682970

RESUMO

The first complete measurement of the ß-decay strength distribution of _{17}^{45}Cl_{28} was performed at the Facility for Rare Isotope Beams (FRIB) with the FRIB Decay Station Initiator during the second FRIB experiment. The measurement involved the detection of neutrons and γ rays in two focal planes of the FRIB Decay Station Initiator in a single experiment for the first time. This enabled an analytical consistency in extracting the ß-decay strength distribution over the large range of excitation energies, including neutron unbound states. We observe a rapid increase in the ß-decay strength distribution above the neutron separation energy in _{18}^{45}Ar_{27}. This was interpreted to be caused by the transitioning of neutrons into protons excited across the Z=20 shell gap. The SDPF-MU interaction with reduced shell gap best reproduced the data. The measurement demonstrates a new approach that is sensitive to the proton shell gap in neutron rich nuclei according to SDPF-MU calculations.

2.
Phys Rev Lett ; 130(24): 242501, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37390416

RESUMO

Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-µs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{32}Na nuclei. This is the only known microsecond isomer (1 µs≤T_{1/2}<1 ms) in the region. This nucleus is at the heart of the N=20 island of shape inversion and is at the crossroads of the spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of a proton hole and neutron particle to ^{32}Mg, ^{32}Mg+π^{-1}+ν^{+1}. This odd-odd coupling and isomer formation provides a sensitive measure of the underlying shape degrees of freedom of ^{32}Mg, where the onset of spherical-to-deformed shape inversion begins with a low-lying deformed 2^{+} state at 885 keV and a low-lying shape-coexisting 0_{2}^{+} state at 1058 keV. We suggest two possible explanations for the 625-keV isomer in ^{32}Na: a 6^{-} spherical shape isomer that decays by E2 or a 0^{+} deformed spin isomer that decays by M2. The present results and calculations are most consistent with the latter, indicating that the low-lying states are dominated by deformation.


Assuntos
Núcleo Celular , Coração , Isótopos , Nêutrons
3.
Phys Rev Lett ; 129(21): 212501, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461950

RESUMO

New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the latest quasiparticle random phase approximation and shell-model calculations. Overall, the measured half-lives are consistent with the available theoretical descriptions and suggest a well-developed region of deformation below ^{48}Ca in the N=28 isotones. The erosion of the Z=14 subshell closure in Si is experimentally confirmed at N=28, and a reduction in the ^{38}Mg half-life is observed as compared with its isotopic neighbors, which does not seem to be predicted well based on the decay energy and deformation trends. This highlights the need for both additional data in this very exotic region, and for more advanced theoretical efforts.

4.
J Biol Regul Homeost Agents ; 32(5): 1055-1059, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30334398

RESUMO

Atherosclerosis and disease of graft implanted to bypass occluded coronary or peripheral arteries are similar processes. Patency of implanted grafts is of paramount importance in respect to long-term outcomes. Although few cell types participate in atherosclerotic plaque formation, macrophages play a crucial role. In this article we review the fate of monocytes that infiltrate vessel wall following endothelium damage, and then undergo transformation to macrophages (identified as CD68 positive cells) and eventually lead to severe stenosis of vessel. Opposing biological activity of two subpopulations of macrophages and their impact on plaque instability and its calcification is also presented. At the end of this paper, a possible clinical significance of pre-existing, CD68 positive cell infiltration of vessel wall, applied as aortocoronary grafts, is discussed.


Assuntos
Aterosclerose/patologia , Ponte de Artéria Coronária , Rejeição de Enxerto/patologia , Macrófagos/patologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Aterosclerose/imunologia , Ponte de Artéria Coronária/efeitos adversos , Rejeição de Enxerto/imunologia , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo
5.
J Biol Regul Homeost Agents ; 32(5): 1129-1141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30334405

RESUMO

Extraordinary abilities for continuous proliferation and differentiation, associated with constant renewal triggered by stimulation from the mastication process, together with the relative lack of aesthetic complications associated with post-surgery healing, have highlighted buccal pouch mucosa as a potential source of explants that could be used in transplantation and tissue engineering. Additionally, this tissue plays a major role in the oral drug delivery process, which brings special interest to its molecular properties in the context of new drug development. There is therefore a need to analyse the exact mechanisms of oral mucosa functioning, especially when it comes to the processes that are associated with the potential clinical applications. In this study we analysed a complete transcriptome of long-term in vitro cultures of porcine buccal pouch oral mucosa cells. Using a microarray approach, we focused on genes associated with cellular metabolic processes, signalling and adhesion, from 4 gene ontology groups: "Positive regulation of cellular component movement", "Positive regulation of cellular process", "Positive regulation of intracellular signal transduction" and "Single organism cell adhesion". Nineteen genes (CCL8, CXCL2, PLK2, DUSP5, PTGS2, LIF, CCL2, ATP1B1, REL, ITGB3, SCARB1, UGCG, PDPN, LYN, ETS1, FCER1G, TGFB1, RFC4, LMO2) with fold changes higher than |2| and p value Extraordinary abilities for continuous proliferation and differentiation, associated with constant renewal triggered by stimulation from the mastication process, together with the relative lack of aesthetic complications associated with post-surgery healing, have highlighted buccal pouch mucosa as a potential source of explants that could be used in transplantation and tissue engineering. Additionally, this tissue plays a major role in the oral drug delivery process, which brings special interest to its molecular properties in the context of new drug development. There is therefore a need to analyse the exact mechanisms of oral mucosa functioning, especially when it comes to the processes that are associated with the potential clinical applications. In this study we analysed a complete transcriptome of long-term in vitro cultures of porcine buccal pouch oral mucosa cells. Using a microarray approach, we focused on genes associated with cellular metabolic processes, signalling and adhesion, from 4 gene ontology groups: "Positive regulation of cellular component movement", "Positive regulation of cellular process", "Positive regulation of intracellular signal transduction" and "Single organism cell adhesion". Nineteen genes (CCL8, CXCL2, PLK2, DUSP5, PTGS2, LIF, CCL2, ATP1B1, REL, ITGB3, SCARB1, UGCG, PDPN, LYN, ETS1, FCER1G, TGFB1, RFC4, LMO2) with fold changes higher than |2| and p value less than 0.05 were identified, described in context and analysed. While the study needs much further validation to become applicable in a clinical environment, it yields valuable information about the transcriptomic basis of oral mucosal cell functioning in vitro, that might serve as a reference for further research, aiming to apply this knowledge in clinical situations.0.05 were identified, described in context and analysed. While the study needs much further validation to become applicable in a clinical environment, it yields valuable information about the transcriptomic basis of oral mucosal cell functioning in vitro, that might serve as a reference for further research, aiming to apply this knowledge in clinical situations.


Assuntos
Adesão Celular/genética , Perfilação da Expressão Gênica , Mucosa Bucal/citologia , Mucosa Bucal/metabolismo , Transdução de Sinais/genética , Suínos , Animais , Técnicas de Cultura de Células , Células Cultivadas , Bochecha , Marcadores Genéticos/genética
6.
Pol J Vet Sci ; 21(2): 383-387, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450879

RESUMO

Previous studies have compared the effectiveness of dinoprost and cloprostenol in cows yielding conflicting results. The aim of our study was to evaluate the efficacy of single treatment with cloprostenol or dinoprost on estrus and reproductive performance in cows with unobserved estrus after service. The study was conducted over four years in two dairy herds of Polish Holstein Frisian cows under a herd health program with an average milk yield per cow over 9000 L. Cows (n=523) diagnosed ultrasonographically as non-pregnant and with a corpus luteum were randomly assigned to be treated with either cloprostenol (n=261) or dinoprost (n=262). The estrus detection rates after administration of cloprostenol or dinoprost were 59.4%, and 57.6%, respectively. The difference between both groups was not statistically significant (p>0.05). Distribution of observed estrus did not differ between cloprostenol and dinoprost. There were no differences (p>0.05) between cloprostenol and dinoprost in conception rate (65.2% vs. 66.2%, respectively) and pregnancy rate (57.5% vs. 54.9%, respectively). Mean days open were similar in cows of both treatments (177.5 ± 74.6 days vs. 175.8 ± 62.6 days, respectively; p>0.05). In conclusion, data from this study showed no significant differences in estrus detection rates and fertility between cows with unobserved estrus after service treated with cloprostenol or dinoprost. Both products are equally useful for the treatment of non-pregnant dairy cows with anestrus after service within a reproductive herd health program.


Assuntos
Cloprostenol , Dinoprosta , Sincronização do Estro , Ocitócicos , Animais , Bovinos , Cloprostenol/uso terapêutico , Dinoprosta/uso terapêutico , Estro , Feminino , Inseminação Artificial , Lactação , Ocitócicos/uso terapêutico , Gravidez , Progesterona
7.
Pol J Vet Sci ; 21(2): 377-381, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450878

RESUMO

There is no information available about the incidence of anestrus and its clinical forms after service in dairy cows in Poland. Thus, the aim of this study was to investigate the incidence of clinical forms of anoestrus after unsuccessful artificial insemination in dairy cows based on ultrasound examination. The study was carried out on 1543 Polish Holstein-Friesian cows in 8 dairy herds in north-east Poland over a three-year period. Cows were examined for pregnancy on day 35 after AI using a Honda 1500 portable ultrasound scanner equipped with a 5 MHz linear-array transducer. Cows diagnosed as pregnant were re-examined on day 45. Of the 1543 inseminated cows, 408 (26.4%) showed no estrus signs and were diagnosed not-pregnant by ultrasonography, 328 (21.3%) returned to estrus within 35 days, and 807 (52.3%) were pregnant via artificial insemination. The incidence of anestrus after service in non-pregnant cows varied among herds from 10.3% to 32.9% of cows (p0.05). Based on ultrasound examination silent heat was diagnosed in 324 (79.4%), corpus luteum pseudograviditatis in 36 (8.8%), ovarian cysts in 26 (6.4%), and ovarian afunction in 22 (5.4%) of 408 anestrous, non-pregnant cows. The results of this study showed that the incidence of anestrus after service in dairy herds in North-East Poland was high. The most prevalent clinical form of post-service anestrus was silent heat.


Assuntos
Anestro , Sincronização do Estro , Inseminação Artificial , Animais , Bovinos , Feminino , Incidência , Inseminação Artificial/veterinária , Polônia , Gravidez , Progesterona
8.
Clin Radiol ; 72(4): 339.e7-339.e15, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28038779

RESUMO

AIM: To develop a method combining the statistics of the ultrasound backscatter and the Breast Imaging-Reporting and Data System (BI-RADS) classification to enhance the differentiation of breast tumours. MATERIALS AND METHODS: The Nakagami shape parameter m was used to characterise the scatter properties of breast tumours. Raw data from the radiofrequency (RF) echo-signal and B-mode images from 107 (32 malignant and 75 benign) lesions and their surrounding tissue were recorded. Three different characteristic values of the shape parameters of m (maximum [mLmax], minimum [mLmin] and average [mLavg]) and differences between m parameters (Δmmax, Δmmin, Δmavg) of the lesions and their surrounding tissues were assessed. A lesion with a BI-RADS score of 3 was considered benign, while a lesion with a score of 4 was considered malignant (a cut-off of BI-RADS 3/4 was set for all patients). RESULTS: The area under the receiver operating characteristic (ROC) curve (AUC) was equal to 0.966 for BI-RADS, with 100% sensitivity and 54.67% specificity. All malignant lesions were diagnosed correctly, whereas 34 benign lesions were biopsied unnecessarily. In assessing the Nakagami statistics, the sum of the sensitivity and specificity was the best for mLavg (62.5% and 93.33%, respectively). Only four of 20 lesions were found over the cut-off value in BI-RADS of 4a. When comparing the differences in m parameters, Δmavg had the highest sensitivity of 90% (only three of 32 lesions were false negative). These three lesions were classified as BI-RADS category 4c. The combined use of B-mode and mLmin parameter improve the AUC up to 0.978 (p=0.088), compared to BI-RADS alone. CONCLUSION: The combination of the parametric imaging and the BI-RADS assessment does not significantly improve the differentiation of breast lesions, but it has the potential to better identify the group of patients with mainly benign lesions that have a low level of suspicion for malignancy with a BI-RADS score of 4a.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Sistemas de Informação em Radiologia/estatística & dados numéricos , Ultrassonografia Mamária/métodos , Ultrassonografia Mamária/estatística & dados numéricos , Adulto , Idoso , Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
9.
Transpl Infect Dis ; 15(1): 1-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22862907

RESUMO

BACKGROUND: Neutropenic enterocolitis (NE) is a life-threatening complication occurring after intensive chemotherapy; however, no data are available on NE development after hematopoietic stem cell transplantation (SCT). The aim of this study was to determine the incidence, risk factors, and outcome of NE after high-dose chemotherapy and autologous SCT (autoSCT). METHODS: A total of 297 adult patients who qualified for autoSCT with non-Hodgkin's lymphoma (NHL), Hodgkin's disease, multiple myeloma, and acute myeloid leukemia were analyzed. Patients were conditioned with carmustine, etoposide, cytarabine, melphalan (BEAM); melphalan alone; or busulfan and cyclophosphamide (BuCy2), and transplanted with peripheral blood or bone marrow CD34(+) cells. Diagnosis of NE was established in case of neutropenic fever, abdominal pain or diarrhea, and bowel wall thickening >4 mm on abdominal sonography. RESULTS: Neutropenic infections occurred in 262 patients (88%). NE was diagnosed in 32 patients (12%), a median +3 (1-5) days after SCT. Bloodstream infections were present in 18 patients, with gram-negative bacteria in 11 patients. All patients were treated conservatively with carbapenems and total parenteral nutrition with bowel rest. The course of disease was complicated by ileus or septic shock in 9 patients, and was fatal for 3 (9.6%) patients. In univariate analysis, the initial diagnosis of NHL (P = 0.017) and conditioning with BEAM (P = 0.043) had prognostic value. In multivariate analysis, only initial diagnosis of NHL (P = 0.017) had prognostic significance. CONCLUSIONS: NE is a rare but severe complication in patients undergoing autoSCT. Gram-negative bacteria remain the main causative pathogen. Abdominal sonography allows early diagnosis and treatment, effective in most of patients without surgery. In our analysis, NE was seen more often in NHL patients treated with a BEAM regimen.


Assuntos
Antineoplásicos/efeitos adversos , Enterocolite Neutropênica/induzido quimicamente , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto , Idoso , Carbapenêmicos/uso terapêutico , Terapia Combinada , Enterocolite Neutropênica/terapia , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hodgkin/terapia , Humanos , Incidência , Leucemia Mieloide Aguda/terapia , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Análise Multivariada , Nutrição Parenteral , Fatores de Risco , Transplante Autólogo , Adulto Jovem
10.
Pol J Vet Sci ; 26(2): 223-229, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389450

RESUMO

The aim of this study was to evaluate the fertility response of dairy cows with anovulation type I on repeated low doses of GnRH agonist buserelin. The study was conducted on 83 anovulatory and 60 cyclic Polish Holstein Friesian cows. Anovulation type I was defined as small ovaries with follicles of ≤ 5 mm in diameter and without corpus luteum on two examinations in a 7-10 day interval between 50-60 days after parturition. Cows from the experimental group (n=58) received 0.4 µg of buserelin i.m. once a day for 5 consecutive days. Cows from the negative control group (n = 25) received saline. Sixty cyclic cows receiving no treatment served as positive controls. Intervals from calving to estrus and from calving to conception, pregnancy rate 30-35 days and 260 days after AI, and pregnancy loss were calculated. The anovulatory cows had a substantially prolonged calving to conception interval, decreased pregnancy rate and increased pregnancy loss and culling rate compared to cyclic herd mates. The average calving to conception interval was significantly (p⟨0.05) shorter in treated cows compared to non-treated anovulatory cows (153.7 days vs 209.3 days). In conclusion, repeated low doses of GnRH analogue buserelin led to a significant shortening of calving to conception interval. More clinical trials are needed to determine the practical usefulness of this method for the treatment of anovulation type I in dairy cows.


Assuntos
Anovulação , Doenças dos Bovinos , Feminino , Gravidez , Bovinos , Animais , Busserrelina/farmacologia , Anovulação/veterinária , Fertilidade , Corpo Lúteo , Estro
11.
J Eur Acad Dermatol Venereol ; 26(6): 696-703, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21692869

RESUMO

BACKGROUND: Cellulite affects nearly 85% of the female population. Given the size of the phenomenon, we are continuously looking for effective ways to reduce cellulite. Reliable monitoring of anticellulite treatment remains a problem. OBJECTIVE: The main aim of the study was to evaluate the effectiveness of anticellulite treatment carried out using radiofrequency (RF), which was monitored by classical and high-frequency ultrasound. METHODS: Twenty-eight women underwent anticellulite treatment using RF, 17 women were in the placebo group. The therapy was monitored by classical and high-frequency ultrasound. The examinations evaluated the thickness of the epidermal echo, dermis thickness, dermis echogenicity, the length of the subcutaneous tissue bands growing into the dermis, the presence or absence of oedema, the thickness of subcutaneous tissue as well as thigh circumference and the stage of cellulite (according to the Nürnberger-Müller scale). RESULTS: Cellulite was reduced in 89.286% of the women who underwent RF treatment. After the therapy, the following observations were made: a decrease in the thickness of the dermis and subcutaneous tissue, an increase in echogenicity reflecting on the increase in the number of collagen fibres, decreased subcutaneous tissue growing into bands in the dermis, and the reduction of oedema. In the placebo group, no statistically significant changes of the above parameters were observed. CONCLUSION: Radiofrequency enables cellulite reduction. A crucial aspect is proper monitoring of the progress of such therapy, which ultrasound allows.


Assuntos
Técnicas Cosméticas , Ondas de Rádio , Radioterapia/métodos , Gordura Subcutânea/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Resultado do Tratamento , Ultrassom/instrumentação , Ultrassonografia
12.
Pneumologie ; 66(4): 235-9, 2012 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-22477485

RESUMO

BACKGROUND: In order to counter the rapidly developing loss of function especially in elderly patients with acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) the concept "early geriatric rehabilitation in acute inpatient pneumology" was developed. An essential aspect of the project was a targeted approach making use of multi-professional expertise and standards. METHODS: This 1-year feasibility study included a total of 58 patients with AE-COPD in advanced age (mean: 74.8 ± 6.8 years) with typical geriatric multimorbidity and necessity for acute medical as well as rehabilitation treatment. The results of the early geriatric rehabilitation by a multi-professional rehabilitation team were analyzed in a prospective study approach using standardized assessments. RESULTS: The early geriatric rehabilitation started on median day 3 (range: 1st - 22nd) and lasted in median 16 days (range: 9 - 29). It achieved a significant improvement, particularly in mobility [timed up-and-go, median 19 (range: 10 - 150) vs. 15 (range: 7 - 120) seconds, p < 0.0001], self-help ability [Barthel index, median 73 (range: 5 - 95) vs. 95 (range: 45 - 100) points, p < 0.0001] and social care. CONCLUSIONS: Early geriatric rehabilitation in a cohort of AE-COPD patients is feasible and can be integrated in an acute inpatient pulmonary care system.


Assuntos
Serviços de Saúde para Idosos/organização & administração , Doença Pulmonar Obstrutiva Crônica/reabilitação , Recuperação de Função Fisiológica , Reabilitação/organização & administração , Idoso , Feminino , Humanos , Masculino , Resultado do Tratamento
13.
Pol J Vet Sci ; 25(3): 391-396, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36155983

RESUMO

The aim of the study was to evaluate the effect of repeated low doses of GnRH agonist buserelin once a day for 5 days on follicle development and ovulation in anovulatory dairy cows with follicles growth only to emergence. The study was conducted on 71 anovulatory Polish Holstein Friesian cows. Anovulation with growth of follicles to emergence was defined as small ovaries with follicles of ≤ 5 mm in diameter and without corpus luteum on two examinations in a 7-10 day interval between 50-60 days after parturition. Cows were allocated to one of two group. Cows from group 1 (n = 58) received 0.4 µg of buserelin (Receptal, MSD, Poland) i.m. once a day for 5 days. Control cows from group 2 (n = 13) received saline. Ovarian structures were monitored weekly after the end of treatment by ultrasound for 4 weeks. The diameter of ovarian follicles on the ovaries was measured and recorded. Occurrence of ovulation was determined by the presence of corpus luteum. Overall, ovulation occurred in 46.6% (27/58) of cows treated with repeated doses of GnRH, while no corpus luteum was observed in the control group during the study period. There were significantly (p⟨0.05) more follicles 6-9 mm in diameter and 10-20 mm in diameter in cows treated with GnRH than in control cows. In conclusion, repeated low doses of GnRH analogue buserelin once a day for 5 days stimulate the development of ovarian follicles in anovulatory dairy cows with small ovarian follicles and led to ovulation in 46.6% of cows during 4 weeks after the end of the treatment.


Assuntos
Anovulação , Doenças dos Bovinos , Animais , Anovulação/veterinária , Busserrelina/farmacologia , Bovinos , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Folículo Ovariano , Ovulação , Progesterona/farmacologia
14.
Ultrasonics ; 126: 106825, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36007292

RESUMO

In our research we present a new method of differential compression of the Golay encoded ultrasound (DCGEU) in the standard beamforming mode to visualize the slow (<1cm/s) blood mimicking fluid flow in small diameter tubes. The proposed DCGEU method is based on synthesis of several subsequent B-mode frames acquired with certain time intervals (30 ms in this study) followed by the visualization of differential beamformed radio frequency (RF) echoes, which yielded the images of the scatterers moving slowly in the vessel and suppressing the static echoes outside the vessel. In order to extract small backscattered echoes from the vessel area we took an advantage of improved sensitivity of the complementary Golay coded sequences (CGCS). The validation of the proposed DCGEU method was carried out in two stages. In the first one, we compared the flow images in small tubes with a diameter of 1 mm and 2.5 mm, reconstructed from numerically simulated acoustic data for the standard transmission of short pulses and 16-bits long CGCS signals. In the second stage of the research, the experimental data were acquired in a flow phantom with silicone tubes with an internal diameter of 1.5 mm and 4.5 mm and a fluid flow velocity of 0.9 cm/s. The experiments were carried out using preprogrammed Verasonics Vantage™ research ultrasound system equipped with ALT L12-5/50 mm MHz linear array transducer with 7.8 MHz center frequency. It was evidenced both in simulations and experiments that the DCGEU provided a good flow image along the entire length of tubing with virtually angle independent detection in comparison with the conventional short pulse interrogation.


Assuntos
Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia/métodos
15.
J Acoust Soc Am ; 130(4): 1908-18, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21973345

RESUMO

The integral equations that describe scattering in the media with step-rise changing parameters have been numerically solved for the trabecular bone model. The model consists of several hundred discrete randomly distributed elements. The spectral distribution of scattering coefficients in subsequent orders of scattering has been presented. Calculations were carried on for the ultrasonic frequency ranging from 0.5 to 3 MHz. Evaluation of the contribution of the first, second, and higher scattering orders to total scattering of the ultrasounds in trabecular bone was done. Contrary to the approaches that use the µCT images of trabecular structure to modeling of the ultrasonic wave propagation condition, the 3D numerical model consisting of cylindrical elements mimicking the spatial matrix of trabeculae, was applied. The scattering, due to interconnections between thick trabeculae, usually neglected in trabecular bone models, has been included in calculations when the structure backscatter was evaluated. Influence of the absorption in subsequent orders of scattering is also addressed. Results show that up to 1.5 MHz, the influence of higher scattering orders on the total scattered field characteristic can be neglected while for the higher frequencies, the relatively high amplitude interference peaks in higher scattering orders clearly occur.


Assuntos
Osso e Ossos/diagnóstico por imagem , Modelos Biológicos , Som , Ultrassom/métodos , Absorção , Simulação por Computador , Imageamento Tridimensional , Microscopia Acústica , Movimento (Física) , Análise Numérica Assistida por Computador , Porosidade , Pressão , Espalhamento de Radiação
16.
Pol J Vet Sci ; 24(3): 433-437, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34730301

RESUMO

The study was carried out in 5 dairy herds of Polish Holstein-Friesian cows. The average milk yield was about 9000 kg per year. For each herd, the following fertility parameters were calculated at the start of the program and 4 years later: first- service conception rate, services per conception, length of inter-calving period and culling rate due to infertility. The incidence of silent heat, ovarian cysts, ovarian afunction, retained placenta and clinical endometritis was also recorded. Four years after implementation of the program, the average first-service conception rate increased from 43.2% to 51.2%. In three herds the differences were statistically significant (p⟨0.05). There was also a decrease in the number of services per pregnancy and in the culling rate due to infertility. Fertility performance was maintained in two herds. The average incidence of silent heat decreased from 38.1% to 29.7% and the difference was statistically significant (p⟨0.05) in three herds. There was no significant reduction in incidence of other reproductive disorders during the 4 years except for clinical endometritis in one herd. The average milk yield increased from 9300 kg to 9530 kg milk per cow per year. In conclusion, the results indicate that the implementation of the integrated veterinary herd health program improved or maintained fertility performance despite an increase in milk yield.


Assuntos
Criação de Animais Domésticos/métodos , Doenças dos Bovinos/prevenção & controle , Medicina Veterinária/organização & administração , Animais , Bovinos , Indústria de Laticínios , Feminino , Fertilidade , Incidência , Lactação , Leite , Gravidez
17.
Pol J Vet Sci ; 24(3): 351-354, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34730309

RESUMO

The aim of this study was to evaluate the efficacy of the Ovsynch protocol in the treatment of post-service subestrus in individual dairy cows compared to a single administration of PGF2α. The study was performed on 517 Polish Friesian Holstein cows with post-service anestrus over four years in 3 dairy herds under a herd health program. Cows (n=240) diagnosed ultrasonographically as non-pregnant and with a mature corpus were treated with a single PGF2α administration and inseminated at detected estrus. Cows without corpus (n=277) were treated with the Ovsynch protocol. The estrus detection rate after PGF2α administration, percentages of cows pregnant after the treatment and at day 260, intervals from parturition to treatment and from treatment to conception and pregnancy loss rates were calculated. The overall percentage of cows pregnant after treatment did not differ between animals treated with the Ovsynch protocol and with PGF2α (38.9% vs. 42.5%; p>0.05). In herd A the percentage of cows pregnant after treatment was significantly lower (p⟨0.05) for the Ovsynch group than for the PGF2α group (30.2% vs. 61.2%). In contrast, in herd C the percentage of cows pregnant after treatment was significantly higher (p⟨0.05) in the Ovsych group than in the PGF2α group (39.6% vs. 28.8%). The overall estrus detection rate after administration of PGF2α was 59.6%. However, it was significantly lower (p⟨0.05) in herd C (44.7%) than in herds A (79.6%) and B (76.3%). The overall pregnancy loss rate ranged from 5.1% to 13.3% and did not differ significantly between herds and treatment groups (p>0.05). In conclusion, Ovsynch protocol can be a useful alternative for treatment of post-service suboestrus in individual cows in dairy herds with insufficient oestrus detection.


Assuntos
Bovinos , Dinoprosta/farmacologia , Sincronização do Estro/métodos , Hormônio Liberador de Gonadotropina/farmacologia , Animais , Dinoprosta/administração & dosagem , Esquema de Medicação , Estro , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial , Gravidez
18.
Ultrasonics ; 115: 106434, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33878528

RESUMO

Complementary Golay coded sequences (CGCS) have several advantages over conventional short pulse transmitted signals. Specifically, CGCS allow the signal-to-noise ratio (SNR) to be increased. Moreover, due to matched filtering and compression, echoes resembling the short pulse waveform with substantially higher amplitude can be obtained. However, CGCS require two subsequent transmissions to obtain a single compressed signal. This decreases the data acquisition rate and the frame rate of ultrasound imaging by two-fold. To alleviate this problem, mutually orthogonal Golay complementary sequences (MOGCS) can be used. MOGCS allow the simultaneous transmission of two CGCS pairs to be implemented, yielding the acoustic data for two image frames in one data acquisition cycle. The main objective of this work was an experimental study of the most crucial parameters of the received acoustic signals, e.g. the signal-to-noise ratio (SNR), the side-lobes level (SLL) of the signal and the axial resolution, obtained from simultaneous transmission of two pairs of CGCS comprising a MOGCS set to demonstrate their feasibility of being used in ultrasonography. For this purpose, a simultaneous synthetic transmit aperture method (SSTA) was proposed. The SSTA is based on MOGCS transmission and simultaneous reconstruction of two image frames from a single data acquisition cycle. This doubles the image reconstruction rate in comparison with conventional CGCS signals. In this paper, the ultrasound data from a perfect reflector, commercial phantoms and in vivo measurements were analysed. Two 16-bit long CGCS pairs comprising the MOGCS set were programmed and transmitted using the Verasonics Vantage™ research ultrasound system equipped with a Philips ATL L7-4 linear array ultrasound probe. It was shown that the signal parameters and overall quality of reconstructed B-mode images did not deteriorate when using the MOGCS in comparison to the conventional CGCS and short pulse signals explored so far.


Assuntos
Aumento da Imagem/métodos , Ultrassonografia/métodos , Compressão de Dados , Humanos , Processamento de Imagem Assistida por Computador , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído
19.
Artigo em Inglês | MEDLINE | ID: mdl-32871376

RESUMO

Hydrogen sulfide is a toxic gas involved in the regulation of some essential biological processes. A novel, precise, accurate and rapid method based on high-performance liquid chromatography with diode array detection for the determination of sulfide ions in human urine sample is proposed. The method involves the derivatization of sulfide with pyrylium salts - (2,4,6-triphenylpyrylium hydrogensulfate(VI) (L1) and 4-[p-(N,N-dimethylamino)phenyl]-2,6-diphenylpyrylium chlorate(VII) (LN1). The separation occurs on InfinityLab Poroshell 120 EC C18 column using acetonitrile and phosphate buffer as a mobile phase. The detectors utilized a wavelength of 371 or 580 nm. The calibration curves were linear in the range of 2-150 µmol L-1 and 1-50 µmol L-1 for L1 and LN1 derivatives, respectively. The samples were found to be stable from sample collection to final analysis. The method was successfully applied to samples from apparently healthy volunteers.


Assuntos
Derivados de Benzeno/química , Cromatografia Líquida de Alta Pressão/métodos , Sulfetos/urina , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Sais/química
20.
Pol J Vet Sci ; 22(1): 157-161, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30997774

RESUMO

The objective of this study was to evaluate the effect of a second prostaglandin F2α (PGF2α) treatment during Ovsynch on luteal regression and fertility in dairy cows, compared with standard Ovsynch. The study was conducted on 111 Holstein Friesian multiparous cows on commercial dairy farm. The cows in the experimental group (n=48) received two treatments of PGF2α 24 hours apart during Ovsynch. The cows in the control group (n=63) were synchronized with standard Ovsynch. To assess the progesterone (P4) concentration blood samples were collected at the day of PGF2α treatment and at the 2nd GnRH treatment. Pregnancy was evaluated by ultrasound examination 37-40 days after timed artificial insemination (TAI) by ultrasound. Cows diagnosed pregnant were re-examined between days 70-80 after TAI. The percentage of cows with complete corpus luteum (CL) regression (P4⟨0.5 ng/ml at the time of the 2nd GnRH treatment) was 89.6 % after two PGF2α treatments and 88.9 % after one PGF2α treatment. There were no statistically significant differences (p>0.05) in the pregnancies per artificial insemination (P/AI) between the experimental and control group (P/AI). However, the pregnancy loss rate was lower in cows receiving two PGF2α treatments than in the control animals (0.0 % vs. 6.4 %; p⟨0.05). In conclusion, the second PGF2α treatment during Ovsynch protocol had no significant effect on CL regression and P/AI in dairy cows. The pregnancy losses until days 75-80 after TAI were significantly lower after two PGF2α treatments than after one PGF2α treatment.


Assuntos
Bovinos/fisiologia , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Sincronização do Estro/métodos , Fertilidade/efeitos dos fármacos , Animais , Busserrelina/administração & dosagem , Busserrelina/farmacologia , Esquema de Medicação , Feminino , Inseminação Artificial/veterinária , Gravidez
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