Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 145
Filtrar
1.
Immunobiology ; 226(3): 152088, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33838552

RESUMO

Dendritic cells (DC) and T-cells are mediators of CTL-responses. Autologous (from patients with acute myeloid leukaemia (AML) or myelodysplasia (MDS)) or allogeneic (donor)-T-cells stimulated by DCleu, gain an efficient lysis of naive blasts, although not in every case. CXCL8, -9, -10, CCL2, -5 and Interleukin (IL-12) were quantified by Cytometric Bead Array (CBA) in supernatants from 5 DC-generating methods and correlated with AML-/MDS-patients' serum-values, DC-/T-cell-interactions/antileukemic T-cell-reactions after mixed lymphocyte culture (MLC) and patients' clinical course. The blast-lytic activity of T-cells stimulated with DC or mononuclear cells (MNC) was quantified in a cytotoxicity assay. Despite great variations of chemokine-levels, correlations with post-stimulation (after stimulating T-cells with DC in MLC) improved antileukemic T-cell activity were seen: higher released chemokine-values correlated with improved T-cells' antileukemic activity (compared to stimulation with blast-containing MNC) - whereas with respect to the corresponding serum values higher CXCL8-, -9-, and -10- but lower CCL5- and -2-release correlated with improved antileukemic activity of DC-stimulated (vs. blast-stimulated) T-cells. In DC-culture supernatants higher chemokine-values correlated with post-stimulation improved antileukemic T-cell reactivity, whereas higher serum-values of CXCL8, -9, and -10 but lower serum-values of CCL5 and -2 correlated with post-stimulation improved antileukemic T-cell-reactivity. In a context of 'DC'-stimulation (vs serum) this might point to a change of (CCL5 and -2-associated) functionality from a more 'inflammatory' or 'tumor-promoting' to a more 'antitumor'-reactive functionality. This knowledge could contribute to develop immune-modifying strategies that promote antileukemic (adaptive) immune-responses.


Assuntos
Quimiocinas/biossíntese , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Quimiocinas/sangue , Citotoxicidade Imunológica , Células Dendríticas/patologia , Humanos , Imunidade , Leucemia Mieloide Aguda/diagnóstico , Ativação Linfocitária/imunologia , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/etiologia , Síndromes Mielodisplásicas/metabolismo , Linfócitos T/patologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia
2.
Sci Rep ; 10(1): 20207, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214618

RESUMO

A lens-free microscope is a simple imaging device performing in-line holographic measurements. In the absence of focusing optics, a reconstruction algorithm is used to retrieve the sample image by solving the inverse problem. This is usually performed by optimization algorithms relying on gradient computation. However the presence of local minima leads to unsatisfactory convergence when phase wrapping errors occur. This is particularly the case in large optical thickness samples, for example cells in suspension and cells undergoing mitosis. To date, the occurrence of phase wrapping errors in the holographic reconstruction limits the application of lens-free microscopy in live cell imaging. To overcome this issue, we propose a novel approach in which the reconstruction alternates between two approaches, an inverse problem optimization and deep learning. The computation starts with a first reconstruction guess of the cell sample image. The result is then fed into a neural network, which is trained to correct phase wrapping errors. The neural network prediction is next used as the initialization of a second and last reconstruction step, which corrects to a certain extent the neural network prediction errors. We demonstrate the applicability of this approach in solving the phase wrapping problem occurring with cells in suspension at large densities. This is a challenging sample that typically cannot be reconstructed without phase wrapping errors, when using inverse problem optimization alone.

3.
Immunol Invest ; 49(4): 365-385, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31535582

RESUMO

In cancer or hematologic disorders, chemokines act as growth- or survival factors, regulating hematopoiesis and angiogenesis, determining metastatic spread and controlling leukocyte infiltration into tumors to inhibit antitumor immune responses. The aim was to quantify the release of CXCL8, -9, -10, CCL2, -5, and IL-12 in AML/MDS-pts' serum by cytometric bead array and to correlate data with clinical subtypes and courses. Minimal differences in serum-levels subdivided into various groups (e.g. age groups, FAB-types, blast-proportions, cytogenetic-risk-groups) were seen, but higher release of CXCL8, -9, -10 and lower release of CCL2 and -5 tendentially correlated with more favorable subtypes (<50 years of age, <80% blasts in PB). Comparing different stages of the disease higher CCL5-release in persisting disease and a significantly higher CCL2-release at relapse were found compared to first diagnosis - pointing to a change of 'disease activity' on a chemokine level. Correlations with later on achieved response to immunotherapy and occurrence of GVHD were seen: Higher values of CXCL8, -9, -10 and CCL2 and lower CCL5-values correlated with achieved response to immunotherapy. Predictive cut-off-values were evaluated separating the groups in 'responders' and 'non-responders'. Higher levels of CCL2 and -5 but lower levels of CXCL8, -9, -10 correlated with occurrence of GVHD. We conclude, that in AML-pts' serum higher values of CXCL8, -9, -10 and lower values of CCL5 and in part of CCL2 correlate with more favorable subtypes and improved antitumor'-reactive function. This knowledge can contribute to develop immune-modifying strategies that promote antileukemic adaptive immune responses.


Assuntos
Citocinas/sangue , Leucemia Mieloide Aguda/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoterapia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Transplante de Células-Tronco
4.
J Perinatol ; 38(1): 71-74, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29048409

RESUMO

OBJECTIVE: Human milk (donor milk (DM) and/or maternal milk (MM)) feedings protect against late onset sepsis (LOS), necrotizing enterocolitis (NEC) and death. However, DM lacks many anti-infective components of MM. Therefore, we studied exclusive MM feedings to evaluate the full effect of human milk on infectious and other outcomes in premature infants. STUDY DESIGN: All infants born before 33 weeks postmenstrual age (PMA) who received exclusive (>95%) MM or exclusive preterm formula (PF) were included in this prospective investigation. RESULTS: Sixty-three infants (53%) received MM and 55 infants (47%) received PF. Both groups had similar baseline characteristics. Infants in the MM group achieved full enteral nutrition sooner (14±8 vs 19±15 days, P<0.03) and required a shorter duration of central venous lines (14±10 vs 22±21, P<0.005). Fewer infants in the MM group developed LOS (9 vs 19, P<0.05) and pneumonia (8 vs 16, P<0.05) than PF infants. Only one MM and five PF infants developed NEC (Bell stage ⩾II). Logistic regression analysis using PMA and prolonged rupture of membranes as covariates demonstrated an increased rate of NEC (odds ratio=8.85, CI=1.01 to 25.17, P=0.048) in PF infants. Periventricular leukomalacia (PVL) was more common in PF (4 vs 0, P=0.04) than in MM infants. CONCLUSION: Feedings of MM advanced more rapidly and were associated with fewer infections than PF. A possible protective effect of MM against PVL, not previously described, may be related to its immune and anti-inflammatory components.


Assuntos
Fórmulas Infantis , Doenças do Prematuro/prevenção & controle , Recém-Nascido Prematuro , Leite Humano , Nutrição Enteral , Enterocolite Necrosante/prevenção & controle , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Pneumonia/prevenção & controle , Estudos Prospectivos , Sepse/prevenção & controle
5.
Ann Hematol ; 96(12): 1993-2003, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29090343

RESUMO

We describe genetic and clinical characteristics of acute myeloid leukemia (AML) patients according to age from an academic population-based registry. Adult patients with newly diagnosed AML at 63 centers in Germany and Austria were followed within the AMLSG BiO registry (NCT01252485). Between January 1, 2012, and December 31, 2014, data of 3525 patients with AML (45% women) were collected. The median age was 65 years (range 18-94). The comparison of age-specific AML incidence rates with epidemiological cancer registries revealed excellent coverage in patients < 70 years old and good coverage up to the age of 80. The distribution according to the European LeukemiaNet (ELN) risk categorization from 2010 was 20% favorable, 31% intermediate-1, 28% intermediate-2, and 21% adverse. With increasing age, the relative but not the absolute prevalence of patients with ELN favorable and intermediate-1 risk (p < 0.001), with activating FLT3 mutations (p < 0.001), with ECOG performance status < 2 (p < 0.001), and with HCT-CI comorbidity index < 3 (p < 0.001) decreased. Regarding treatment, obesity and favorable risk were associated with an intensive treatment, whereas adverse risk, higher age, and comorbidity index > 0 were associated with non-intensive treatment or best supportive care. The AMLSG BiO registry provides reliable population-based distributions of genetic, clinical, and treatment characteristics according to age.


Assuntos
Leucemia Mieloide Aguda , Mutação , Sistema de Registros , Tirosina Quinase 3 Semelhante a fms , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria , Feminino , Alemanha , Humanos , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
7.
Leukemia ; 31(6): 1286-1295, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27881874

RESUMO

We studied acute myeloid leukemia (AML) patients with lympho-myeloid clonal hematopoiesis (LM-CH), defined by the presence of DNA methyltransferase 3A (DNMT3A) mutations in both the myeloid and lymphoid T-cell compartment. Diagnostic, complete remission (CR) and relapse samples were sequenced for 34 leukemia-related genes in 171 DNMT3A mutated adult AML patients. AML with LM-CH was found in 40 patients (23%) and was associated with clonal hematopoiesis of indeterminate potential years before AML, older age, secondary AML and more frequent MDS-type co-mutations (TET2, RUNX1 and EZH2). In 82% of AML patients with LM-CH, the preleukemic clone was refractory to chemotherapy and was the founding clone for relapse. Both LM-CH and non-LM-CH MRD-positive AML patients who achieved CR had a high risk of relapse after 10 years (75% and 75%, respectively) compared with patients without clonal hematopoiesis in CR with negative MRD (27% relapse rate). Long-term survival of patients with LM-CH was only seen after allogeneic hematopoietic stem cell transplantation (HSCT). We define AML patients with LM-CH as a distinct high-risk group of AML patients that can be identified at diagnosis through mutation analysis in T cells and should be considered for HSCT.


Assuntos
Células Clonais , Hematopoese , Leucemia Mieloide Aguda/patologia , Células Progenitoras Linfoides/patologia , Células Progenitoras Mieloides/patologia , Recidiva Local de Neoplasia/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Terapia Combinada , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Resistencia a Medicamentos Antineoplásicos , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Células Progenitoras Linfoides/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Células Progenitoras Mieloides/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Adulto Jovem
8.
Geburtshilfe Frauenheilkd ; 75(5): 442-449, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26097247

RESUMO

Aims: Laparoscopic myomectomy (LM) has been the gold standard treatment for uterine fibroids in women desiring uterine conservation. To evaluate a new fibroid treatment modality - radiofrequency volumetric thermal ablation (RFVTA) - we compare 12-month results in women who had symptomatic uterine fibroids and who were randomized to laparoscopic ultrasound-guided RFVTA or LM. Materials and Methods: Our study is a 1 : 1 parallel, randomized, prospective, single-center, longitudinal, comparative analysis of RFVTA to LM for fibroid treatment in women ≥ 18 years of age who desired uterine conservation. Fifty women were randomized intraoperatively to RFVTA (n = 25) or to LM (n = 25) after laparoscopic ultrasound mapping of the uterus. Results: Post surgery, ablation and myomectomy subjects took pain medications for 4 days (range: 1-46) and 7 days (range: 1-83 days) respectively (p = 0.60). Ablation and myomectomy subjects missed 10.0 workdays (range: 2-86 days) and 17.0 workdays (range: 7-30 days) (p = 0.28), resumed normal activities in 20.5 days (range: 5-103 days) versus 28.0 days (range: 10-42 days) (p = 0.86) respectively. Mean symptom severity scores decreased (improved) by - 7.8 for the ablation subjects and by - 17.9 for the myomectomy subjects (p = 0.16). Health-related quality of life improved (increased) by 7.5 and 13.1, respectively, for the two groups (p = 0.46). Two myomectomy subjects had pregnancies that ended in a Cesarean delivery and a vaginal delivery of healthy infants. Two pregnancies in the RFVTA group ended in full-term vaginal deliveries of healthy infants. Conclusions: Early postoperative recovery and twelve-month results attest to similar clinical benefits from RFVTA and LM.

9.
Pathologica ; 107(3-4): 177-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26946872

RESUMO

INTRODUCTION: Despite the improvement of diagnostic methods and chemotherapeutic regimens in breast cancer, overall 5-year survival significantly depends on the stage of the disease. Over expression of tumor suppressor gene p53 and the marker for cellular proliferation Ki67 in breast cancer may have prognostic significance. METHODS: We evaluated 675 patients diagnosed with breast cancer at UF Health Jacksonville between January 2000 and June 2007 with up to 5-year follow up. The aim of the study was to determine whether immunohistochemical (IHC) assessment of Ki67 and p53 may predict outcome, the 'hazard' of dying. Cox's proportional hazards models were used to control for age (< 50 vs. ≥ 50), race (white vs. other), lymph node group (negative vs. positive), ER (estrogen receptor) group (negative vs. positive), PR (progesterone receptor) group (negative vs. positive), and tumor type. RESULTS: When only p53 was considered in the model, the hazard of dying was significantly higher for p53 positive compared to p53 negative (HR = 1.32, 95% CI 1.02, 1.70, p = 0.036). When only ki67 was considered in the model, the hazard of dying was significantly higher for ki67 positive compared to ki67 negative (Hazard ratio = 1.64, 95% CI 1.08, 2.49, p = 0.021). Neither of the two markers, nor their interaction was significant when all variables were considered in the model. DISCUSSION: This study confirms the expression of p53 and Ki67 as strong individual indicators of patient outcome. However, when controlling for the other variables, the two markers are not independent predictors. Future studies that will include these markers might help design targeted therapy.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Antígeno Ki-67/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma/mortalidade , Carcinoma/terapia , Feminino , Florida/epidemiologia , Seguimentos , Humanos , Pessoa de Meia-Idade , Medicina de Precisão , Estudos Retrospectivos
10.
J Perinatol ; 34(11): 858-62, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25144159

RESUMO

OBJECTIVE: Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC. STUDY DESIGN: We used a case-control design to match each case of NEC in our study population of infants born at<33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth. RESULT: The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11). CONCLUSION: In contrast to previous studies, our case-control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC.


Assuntos
Enterocolite Necrosante/epidemiologia , Transfusão de Eritrócitos/métodos , Doenças do Prematuro/epidemiologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Análise por Pareamento , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco
11.
Rev Sci Instrum ; 85(4): 045107, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24784659

RESUMO

Advances in thermoelectric materials in recent years have led to significant improvements in thermoelectric device performance and thus, give rise to many new potential applications. In order to optimize a thermoelectric device for specific applications and to accurately predict its performance ideally the material's figure of merit ZT as well as the individual intrinsic properties (Seebeck coefficient, electrical resistivity, and thermal conductivity) should be known with high accuracy. For that matter, we developed two experimental methods in which the first directly obtains the ZT and the second directly measures the individual intrinsic leg properties of the same p/n-type thermoelectric couple device. This has the advantage that all material properties are measured in the same sample direction after the thermoelectric legs have been mounted in the final device. Therefore, possible effects from crystal anisotropy and from the device fabrication process are accounted for. The Seebeck coefficients, electrical resistivities, and thermal conductivities are measured with differential methods to minimize measurement uncertainties to below 3%. The thermoelectric couple ZT is directly measured with a differential Harman method which is in excellent agreement with the calculated ZT from the individual leg properties. The errors in both the directly measured and calculated thermoelectric couple ZT are below 5% which is significantly lower than typical uncertainties using commercial methods. Thus, the developed technique is ideal for characterizing assembled couple devices and individual thermoelectric materials and enables accurate device optimization and performance predictions. We demonstrate the methods by measuring a p/n-type thermoelectric couple device assembled from commercial bulk thermoelectric Bi2Te3 elements in the temperature range of 30 °C-150 °C and discuss the performance of the couple thermoelectric generator in terms of its efficiency and materials' self-compatibility.

12.
Rev Sci Instrum ; 85(2): 025108, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593397

RESUMO

Accurate measurements of thermal conductivity are of great importance for materials research and development. Steady-state methods determine thermal conductivity directly from the proportionality between heat flow and an applied temperature difference (Fourier Law). Although theoretically simple, in practice, achieving high accuracies with steady-state methods is challenging and requires rather complex experimental setups due to temperature sensor uncertainties and parasitic heat loss. We developed a simple differential steady-state method in which the sample is mounted between an electric heater and a temperature-controlled heat sink. Our method calibrates for parasitic heat losses from the electric heater during the measurement by maintaining a constant heater temperature close to the environmental temperature while varying the heat sink temperature. This enables a large signal-to-noise ratio which permits accurate measurements of samples with small thermal conductance values without an additional heater calibration measurement or sophisticated heater guards to eliminate parasitic heater losses. Additionally, the differential nature of the method largely eliminates the uncertainties of the temperature sensors, permitting measurements with small temperature differences, which is advantageous for samples with high thermal conductance values and/or with strongly temperature-dependent thermal conductivities. In order to accelerate measurements of more than one sample, the proposed method allows for measuring several samples consecutively at each temperature measurement point without adding significant error. We demonstrate the method by performing thermal conductivity measurements on commercial bulk thermoelectric Bi2Te3 samples in the temperature range of 30-150 °C with an error below 3%.

13.
Ann Oncol ; 24(6): 1609-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23393125

RESUMO

BACKGROUND: Long-term clinical and molecular remissions in patients with follicular lymphoma (FL) following high-dose therapy (HDT) and autologous stem cell transplantation (ASCT) have been evaluated in only a few studies. Results are especially limited for second-line HDT with BEAM (BCNU, etoposide, cytarabine and melphalan). PATIENTS AND METHODS: Sixty patients with FL received ASCT in our institution (18 first-line with total body irradiation and cyclophosphamide, 34 second-line with BEAM and 8 ≥ third-line with BEAM). In the case of long-term remission (>6 years; N = 17), peripheral blood was tested for minimal residual disease by t(14;18)- and IGH-PCR. RESULTS: Ten-year overall survival, progression-free survival and freedom from progression (FFP) after first-line ASCT were 79%, 57% and 64% after second-line ASCT 41%, 35% and 42%, respectively. Prognostic factors for FFP were treatment line and FLIPI (Follicular Lymphoma International Prognostic Index). Ten-year FFP for second-line ASCT and low-risk FLIPI was 57%, intermediate risk 37% and high risk 33%. No relapses occurred after 6 years following ASCT. Sixteen patients developed sustained long-term clinical and molecular remissions of up to 17.5 years. CONCLUSION: Sustained long-term clinical and molecular remissions can be achieved following ASCT, including HDT with BEAM in second line.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/cirurgia , Transplante de Células-Tronco/métodos , Adulto , Idoso , Carmustina/administração & dosagem , Estudos de Coortes , Terapia Combinada/métodos , Terapia Combinada/mortalidade , Citarabina/administração & dosagem , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfoma Folicular/mortalidade , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Podofilotoxina/administração & dosagem , Indução de Remissão/métodos , Transplante de Células-Tronco/mortalidade , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
14.
Reproduction ; 143(6): 799-813, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22454530

RESUMO

Artificial insemination (AI) with sex-sorted frozen-thawed spermatozoa has led to enhanced management of ex situ bottlenose dolphin populations. Extended distance of animals from the sorting facility can be overcome by the use of frozen-thawed, sorted and recryopreserved spermatozoa. Although one bottlenose dolphin calf had been born using sexed frozen-thawed spermatozoa derived from frozen semen, a critical evaluation of in vitro sperm quality is needed to justify the routine use of such samples in AI programs. Sperm motility parameters and plasma membrane integrity were influenced by stage of the sex-sorting process, sperm type (non-sorted and sorted) and freezing method (straw and directional) (P<0.05). After recryopreservation, sorted spermatozoa frozen with the directional freezing method maintained higher (P<0.05) motility parameters over a 24-h incubation period compared to spermatozoa frozen using straws. Quality of sperm DNA of non-sorted spermatozoa, as assessed by the sperm chromatin structure assay (SCSA), was high and remained unchanged throughout freeze-thawing and incubation processes. Though a possible interaction between Hoechst 33342 and the SCSA-derived acridine orange was observed in stained and sorted samples, the proportion of sex-sorted, recryopreserved spermatozoa exhibiting denatured DNA was low (6.6±4.1%) at 6 h after the second thawing step and remained unchanged (P>0.05) at 24 h. The viability of sorted spermatozoa was higher (P<0.05) than that of non-sorted spermatozoa across all time points after recryopreservation. Collective results indicate that bottlenose dolphin spermatozoa undergoing cryopreservation, sorting and recryopreservation are of adequate quality for use in AI.


Assuntos
Golfinho Nariz-de-Garrafa , Criopreservação , Dano ao DNA/fisiologia , Congelamento/efeitos adversos , Pré-Seleção do Sexo/veterinária , Motilidade dos Espermatozoides/fisiologia , Animais , Golfinho Nariz-de-Garrafa/genética , Golfinho Nariz-de-Garrafa/metabolismo , Golfinho Nariz-de-Garrafa/fisiologia , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Criopreservação/métodos , Feminino , Masculino , Análise do Sêmen/métodos , Análise do Sêmen/veterinária , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Espermatozoides/citologia , Espermatozoides/metabolismo , Espermatozoides/fisiologia
15.
Theriogenology ; 75(1): 24-33, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20833420

RESUMO

The objective was to determine if lipid segregation, with or without post-thaw laser assisted hatching (LAH) of in vitro produced (IVP) bovine embryos, would enhance in vitro survivability and development 24 h post-thaw. On Day 6 of culture (Day 0 = IVF), in vitro produced bovine embryos were divided into three developmental stages: 32-cell (n = 78), compact morula (CM n = 223), and blastocyst (n =56). Embryos within each stage were allocated to the following treatments prior to cryopreservation in 1.5M ethylene glycol: no treatment (Control), 7.5 µg/mL Cytochalasin B for 20 min (CB), or CB with centrifugation (16,000 × g) for 20 min (CBCF). All CB treatments were extended to include embryo freezing. Immediately post-thaw, one-half of the CBCF and Control groups were subjected to zona pellucida drilling (LAH), using the XY Clone® system, creating groups CBCFLAH and LAH, respectively. All thawed embryos were cultured for 24 h and evaluated. No treatment differences were observed for either post-thaw survival or 24 h development. Within the CM stage, CBCFLAH and LAH exhibited a greater number of both total and live cells than Control (total: 69.4, 69.3, 53.0, live: 56.4, 54.7, 39.3 respectively; P < 0.05). In conclusion, LAH post-thaw alone or in combination with CBCF improved embryo viability following cryopreservation.


Assuntos
Bovinos/embriologia , Criopreservação/veterinária , Técnicas de Cultura Embrionária/veterinária , Embrião de Mamíferos/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Centrifugação/veterinária , Citocalasina B/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/ultraestrutura , Desenvolvimento Embrionário , Feminino , Fertilização in vitro/veterinária , Lasers , Zona Pelúcida/ultraestrutura
16.
Theriogenology ; 74(3): 374-83, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20416934

RESUMO

Heat above homeothermy can be detrimental to embryonic development, and cells may produce heat shock proteins to try to mitigate these effects. The authors examined the developmental competence of equine oocytes after a single heat exposure (42 degrees C, 2 or 4 h) during early or late stages of in vitro maturation. Rates of nuclear maturation, cleavage after intracytoplasmic sperm injection, and advanced embryonic development (morula or blastocyst) were compared to those for unexposed controls. Concentrations of heat shock protein 70 (HSPA1A) mRNA were determined by real-time RT-PCR in resulting blastocysts, and were compared to those for embryos derived in vivo from control or exercised mares. Exposure of oocytes to heat at the onset of in vitro maturation did not affect any measured end point. However, exposure to 42 degrees C late in maturation culture reduced rates of oocyte nuclear maturation for both the 2 h (43/105 (43%) compared to control 70/103 (68%); P < 0.01), and 4 h (47/106 (44%) compared to control 60/103 (59%); P < 0.05) groups. Additionally, late heat exposure reduced development to morulae and blastocyst stages after intracytoplasmic sperm injection (ICSI; 18/89 (20%) compared to control 43/128 (34%); P < 0.05). Seven days after oocyte heat exposure, resultant blastocysts had a higher abundance of HSPA1A gene transcripts, relative to those for 18S rRNA. In vitro-produced embryos and lower-quality in vivo-produced embryos had significantly higher relative HSPA1A mRNA (lower 18S rRNA) concentrations than did higher-quality in vivo-produced embryos. The authors concluded that equine oocytes were sensitive to heat during late in vitro maturation, and responded to thermal shock with an increased ratio of HSPA1A:18S gene expression that was measurable in the resulting blastocyst. Embryos produced in vitro (including controls) had increased levels of HSPA1A mRNA relative to 18S rRNA compared to in vivo-produced embryos, suggesting a response to environmental insult.


Assuntos
Blastocisto/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Cavalos/embriologia , Temperatura Alta , Animais , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Choque Térmico HSP70/genética , Resposta ao Choque Térmico , Cavalos/genética , Cavalos/metabolismo , Meiose , Oócitos/metabolismo , Condicionamento Físico Animal , RNA Mensageiro/metabolismo , RNA Ribossômico 18S/metabolismo
17.
J Thromb Haemost ; 8(2): 276-85, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19943872

RESUMO

BACKGROUND: Large animal models that accurately mimic human hemophilia A (HA) are in great demand for developing and testing novel therapies to treat HA. OBJECTIVES: To re-establish a line of sheep exhibiting a spontaneous bleeding disorder closely mimicking severe human HA, fully characterize their clinical presentation, and define the molecular basis for disease. PATIENTS/METHODS: Sequential reproductive manipulations were performed with cryopreserved semen from a deceased affected ram. The resultant animals were examined for hematologic parameters, clinical symptoms, and responsiveness to human FVIII (hFVIII). The full coding region of sheep FVIII mRNA was sequenced to identify the genetic lesion. RESULTS AND CONCLUSIONS: The combined reproductive technologies yielded 36 carriers and 8 affected animals. The latter had almost non-existent levels of FVIII:C and extremely prolonged aPTT, with otherwise normal hematologic parameters. These animals exhibited bleeding from the umbilical cord, prolonged tail and nail cuticle bleeding time, and multiple episodes of severe spontaneous bleeding, including hemarthroses, muscle hematomas and hematuria, all of which responded to hFVIII. Inhibitors of hFVIII were detected in four treated animals, further establishing the preclinical value of this model. Sequencing identified a premature stop codon and frame-shift in exon 14, providing a molecular explanation for HA. Given the decades of experience using sheep to study both normal physiology and a wide array of diseases and the high homology between human and sheep FVIII, this new model will enable a better understanding of HA and facilitate the development and testing of novel treatments that can directly translate to HA patients.


Assuntos
Coagulação Sanguínea/genética , Fator VIII/genética , Hemartrose/genética , Hemofilia A/genética , Fatores Etários , Envelhecimento , Animais , Sequência de Bases , Coagulação Sanguínea/efeitos dos fármacos , Coagulantes/farmacologia , Códon sem Sentido , Análise Mutacional de DNA , Modelos Animais de Doenças , Éxons , Fator VIII/metabolismo , Fator VIII/farmacologia , Feminino , Predisposição Genética para Doença , Hemartrose/sangue , Hemartrose/tratamento farmacológico , Hemartrose/patologia , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Hemofilia A/patologia , Humanos , Masculino , Dados de Sequência Molecular , Tempo de Tromboplastina Parcial , Fenótipo , RNA Mensageiro/sangue , Técnicas de Reprodução Assistida , Ovinos , Especificidade da Espécie
18.
Rev Sci Instrum ; 80(9): 093901, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19791947

RESUMO

The maximum efficiency of a thermoelectric generator is determined by the material's dimensionless figure of merit ZT. Real thermoelectric material properties are highly temperature dependent and are often measured individually using multiple measurement tools on different samples. As a result, reported ZT values have large uncertainties. In this work we present an experimental technique that eliminates some of these uncertainties. We measure the Seebeck coefficient, electrical conductivity, and thermal conductivity of a single element or leg, as well as the conversion efficiency, under a large temperature difference of 2-160 degrees C. The advantages of this technique include (1) the thermoelectric leg is mounted only once and all measurements are in the same direction and (2) the measured properties are corroborated by efficiency measurements. The directly measured power and efficiency are compared to the values calculated from the measured properties and agree within 0.4% and 2%, respectively. The realistic testing conditions of this technique make it ideal for material characterization prior to implementation in a real thermoelectric generator.

19.
Neurologia ; 24(1): 7-8, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19214816

RESUMO

Functional hemispherectomy was reported in 1983 for the treatment of catastrophic refractory epilepsies in order to reduce the complications derived by the anatomical hemispherectomy. A series of variants of the functional hemisphectomy have been reported. They include peri-insular hemispherectomy, modified lateral hemispherectomy, vertical parasagital hemispherectomy. The functional hemispherectomy has been used mainly in the treatment of catastrophic epilepsies in children, in which extensive hemispheric lesions are associated with pharmacoresistant epileptic seizures and focal neurological deficit such as: Rasmussen's encephalitis, hemimegalencephaly, Sturge-Weber syndrome, and extensive hemispheric cortical dysplasias, etc. Recently, two series of adults patients with catastrophic epilepsies with excellent control of the episodes (above 75 %) and without mortality have been reported. Thus, functional hemispherectomy may be an effective procedure in appropriately selected adult patients, although more studies with larger series are still needed to evaluate the long-term prognosis.


Assuntos
Epilepsia/cirurgia , Hemisferectomia , Adulto , Epilepsia/fisiopatologia , Hemisferectomia/estatística & dados numéricos , Humanos , Seleção de Pacientes , Resultado do Tratamento
20.
Anim Reprod Sci ; 110(3-4): 237-44, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18295989

RESUMO

The effect of exercise on mare reproductive efficiency was evaluated by comparing rates of embryo recovery from mares assigned to either an exercise regimen or a non-exercise (control) regimen. Exercised mares were worked daily for 30 min under average ambient conditions of >30 degrees C and >50% humidity. Mares were inseminated during estrus and subjected to uterine flush for embryo recovery on d 7 after ovulation for two consecutive cycles. After this, mares were allocated to the opposite group and allowed an estrous cycle without reproductive manipulation; then insemination and uterine flushing were conducted on two more consecutive cycles. Prostaglandin F(2alpha) was administered on the day of uterine flush. Mare rectal temperature increased during exercise from a mean of 38 degrees C to a mean of 39.9 degrees C. Mares had ovulations from smaller follicles when exercised than they did under control conditions (39.8+/-0.5 compared with 41.5+/-0.5mm diameter; P<0.05), and had an increased time from PGF(2alpha) administration to subsequent ovulation (8.47+/-0.337 compared with 9.27+/-0.294 d; P<0.05). Embryo recovery from control mares was 22 of 35 (63%). Fewer embryos were recovered from exercised mares (11 of 32, 34%; P<0.05). The proportion of embryos classified as Grade 1 tended to be less in exercised than in non-exercised mares (4 of 11, 36% compared with 16 of 22, 73%; P=0.051). These data indicate that exercising mares in a hot and humid environment are associated with changes in ovarian follicle development and ovulation, and a reduction in embryo recovery.


Assuntos
Transferência Embrionária/veterinária , Cavalos/fisiologia , Inseminação Artificial/veterinária , Indução da Ovulação/veterinária , Condicionamento Físico Animal/fisiologia , Animais , Temperatura Corporal/fisiologia , Feminino , Masculino , Condicionamento Físico Animal/efeitos adversos , Gravidez , Distribuição Aleatória
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA