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1.
J Acoust Soc Am ; 151(1): 180, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35105033

RESUMO

This paper investigates the performance of one-eighth Spherical Fraction Microphone Array through experimental measurement to analyze acoustic scenes in one-eighth of space. The array geometry is designed to be placed in a room corner at the junction of three acoustically rigid walls. Two prototypes are built with 8 and 16 microphones, respectively. The sampling strategy is discussed and a spatial aliasing analysis is carried out both analytically and by numerical simulations. The array performances are evaluated through Spherical Fraction Beamforming (SFB). This approach is based on the decomposition of the acoustic pressure field in a rigid bounded domain. The localization angular error and Directivity Index criterion are evaluated for both arrays. In a first experiment, the arrays are mounted in an eighth of space built inside an anechoic room. The results are compared with simulation and show consistency. The theoretical limitations of SFB in a rigid bounded one-eighth of space are retrieved experimentally. These limitations are also observed in a real configuration: an office room. Further investigations on SFB are also conducted in the case of a virtual scene constructed with two sound sources.

2.
J Acoust Soc Am ; 148(3): 1456, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33003845

RESUMO

In recent years, the current technological improvements of unmanned aerial vehicles (UAV) have made drones more difficult to locate using optical or radio-based systems. However, the sound emitted by UAV motorization and the aerodynamic whistling of the UAVs can be exploited using a microphone array and an adequate real time signal processing algorithm. The proposed method takes advantage of the characteristics of the sound emitted by the UAV. The intrinsic harmonic structure of the emitted sound is exploited by a pitch detection algorithm coupled with zero-phase selective bandpass filtering to detect the fundamental of the signal and to extract its specific harmonics. Although three-dimensional position errors are less when signals are filtered within the antenna bandwidth, experimental measurements show that accurate estimates with only a few selected harmonics in the signal can be obtained with the localization process. Kalman filtering is used to smooth the estimates.

3.
Infant Ment Health J ; 36(3): 337-48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25941026

RESUMO

The present study investigated maternal emotion regulation as mediating the association between maternal posttraumatic stress symptoms and children's emotional dysregulation in a community sample of 431 Israeli mothers and children exposed to trauma. Little is known about the specific pathways through which maternal posttraumatic symptoms and deficits in emotion regulation contribute to emotional dysregulation. Inspired by the intergenerational process of relational posttraumatic stress disorder (PTSD), in which posttraumatic distress is transmitted from mothers to children, we suggest an analogous concept of relational emotion regulation, by which maternal emotion regulation problems may contribute to child emotion regulation deficits. Child emotion regulation problems were measured using the Child Behavior Checklist-Dysregulation Profile (CBCL-DP; T.M. Achenbach & I. Rescorla, 2000), which is comprised of three subscales of the CBCL: Attention, Aggression, and Anxiety/Depression. Maternal PTSD symptoms were assessed by the Posttraumatic Diagnostic Scale (E.B. Foa, L. Cashman, L. Jaycox, & K. Perry, 1997) and maternal emotion regulation by the Difficulties in Emotion Regulation Scale (K.L. Gratz & L. Roemer, 2004). Results showed that the child's emotion regulation problems were associated with both maternal posttraumatic symptoms and maternal emotion dysregulation. Further, maternal emotion regulation mediated the association between maternal posttraumatic symptoms and the child's regulation deficits. These findings highlight the central role of mothers' emotion regulation skills in the aftermath of trauma as it relates to children's emotion regulation skills. The degree of mothers' regulatory skills in the context of posttraumatic stress symptoms reflects a key process through which the intergenerational transmission of trauma may occur. Study results have critical implications for planning and developing clinical interventions geared toward the treatment of families in the aftermath of trauma and, in particular, the enhancement of mothers' emotion regulation skills after trauma.


Assuntos
Emoções , Mães/psicologia , Psicologia da Criança , Transtornos de Estresse Pós-Traumáticos , Criança , Transtornos do Comportamento Infantil , Pré-Escolar , Feminino , Humanos , Entrevistas como Assunto , Israel , Relações Mãe-Filho , Violência
4.
Top Companion Anim Med ; 60: 100875, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38631428

RESUMO

Pet obesity is still a major health issue, which is considered an epidemic by some researchers. Prevention is one of the cornerstones of veterinary care, emphasizing the importance of proactive measures. Human lifestyle was affected during the COVID-19 pandemic, resulting in an increased overweight prevalence in the population. The prevalence of overweight and obesity in dogs during this period has been poorly explored. This study's objectives were to assess the percentage of the French dog population with overweight and obesity, compare the results with a study conducted before the COVID-19 pandemic, and investigate any potential changes in the risk factors. The study collected data through a survey completed by dog owners during their pets' vaccination visits at university veterinary hospitals of Maisons-Alfort (Paris) and Toulouse, in France, between 2020 and 2022. The veterinarian recorded the dog's weight and the body condition score using a 9-point scale. The study included a total of 309 dogs. Of these, 1.6 % were underweight, 63.1 % had an ideal body condition, and 35.3 % were overweight, including 2.3 % of all dogs classified as obese. During the pandemic, French dog diets shifted towards increased commercial food consumption and twice-daily feedings compared to a 2003 study. Factors positively associated with overweight were being female (OR = 3.55; 95 % CI: 1.65-8.01; P=0.002), being senior (OR=4.91; 95 % CI: 2.07-12.2; P<0.001) or geriatric (OR=5.81; 95 % CI: 2.04-17.0; P=0.001) and having an owner underestimating dog's body condition (OR=74.1; 95 % CI: 29.8-215; P<0.001). Recognizing the impact of owner perception enables early intervention strategies, such as educating owners during consultations and conducting teaching sessions at the clinic. This proactive approach could contribute to improved health outcomes and help prevent the onset of obesity-related issues in dogs. The new trends in dogs' diets may have global relevance due to the pandemic's widespread impact. Although no immediate impact on overweight is evident, ongoing research is crucial to understand the pandemic's long-term effects.


Assuntos
COVID-19 , Doenças do Cão , Hospitais Veterinários , Obesidade , Sobrepeso , Cães , Animais , COVID-19/veterinária , COVID-19/epidemiologia , COVID-19/prevenção & controle , Obesidade/veterinária , Obesidade/epidemiologia , Doenças do Cão/epidemiologia , Feminino , Masculino , França/epidemiologia , Prevalência , Sobrepeso/veterinária , Sobrepeso/epidemiologia , Fatores de Risco , SARS-CoV-2 , Humanos , Inquéritos e Questionários
7.
Am J Vet Res ; 83(5): 434-442, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35175932

RESUMO

OBJECTIVE: To investigate the effects and duration of orally administered prednisolone on renal function evaluated by glomerular filtration rate (GFR) determination and creatinine (Cr) and symmetric dimethylarginine (SDMA) concentrations as well as on urinalysis, electrolytes, and hydric status in healthy dogs. ANIMALS: 14 healthy Beagles. PROCEDURES: In this prospective double-masked placebo-controlled study, dogs were randomized after baseline evaluation to receive a 7-day course of either prednisolone (1.5 to 2.0 mg/kg, PO, q 12 h) or a placebo. A repeated-measure design was performed, each dog participating in 4 successive sampling sessions. Clinical data, systolic blood pressure, CBC, and biochemical analyses including serum SDMA concentration, GFR determination, urine output quantification, and complete urinalysis were performed for all dogs the day before (D0) and at the end of steroid administration (D7) as well as 2 weeks (D21) and 4 weeks (D35) after the end of treatment. RESULTS: At D7, when compared with baseline, GFR increased significantly in treated dogs, whereas creatinine and SDMA concentrations decreased significantly. GFR and Cr but not SDMA modifications persisted significantly at D21. None of the variables differed significantly from baseline at D35. The OR of presenting an albumin band on urine electrophoresis was 2.4 times as high in treated versus control dogs (OR, 36; 95% CI, 1.8 to 719.4; P = 0.02). CLINICAL RELEVANCE: A short-term course of immune-suppressive prednisolone treatment in healthy dogs leads to a sustained but reversible renal hyperfiltration state. Modification in electrolytic variables can affect the clinical interpretation of blood work in such patients.


Assuntos
Doenças do Cão , Prednisolona , Animais , Biomarcadores , Creatinina , Cães , Eletrólitos , Taxa de Filtração Glomerular/veterinária , Rim/fisiologia , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Estudos Prospectivos
8.
Nat Med ; 4(4): 397-402, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9546783

RESUMO

Immunization with irradiated sporozoites can protect against malaria infection and intensive efforts are aimed at reproducing this effect with subunit vaccines. A particular sequence of subunit immunization with pre-erythrocytic antigens of Plasmodium berghei, consisting of single dose priming with plasmid DNA followed by a single boost with a recombinant modified vaccinia virus Ankara (MVA) expressing the same antigen, induced unprecedented complete protection against P. berghei sporozoite challenge in two strains of mice. Protection was associated with very high levels of splenic peptide-specific interferon-gamma-secreting CD8+ T cells and was abrogated when the order of immunization was reversed. DNA priming followed by MVA boosting may provide a general immunization regime for induction of high levels of CD8+ T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunização Secundária , Vacinas Antimaláricas , Malária/imunologia , Plasmodium berghei/imunologia , Vacinas de DNA , Vaccinia virus/imunologia , Animais , Anopheles/parasitologia , Células Cultivadas , Embrião de Galinha , Citotoxicidade Imunológica , Feminino , Humanos , Interferon gama/biossíntese , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Malária/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmídeos , Plasmodium berghei/crescimento & desenvolvimento , Plasmodium berghei/isolamento & purificação , Especificidade da Espécie , Baço/imunologia
9.
J Med Primatol ; 39(5): 315-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20444002

RESUMO

BACKGROUND: A 9-year-old, male castrate, Rhesus macaque was euthanized following a prolonged history of chronic renal failure. RESULTS: Necropsy revealed a proliferative lesion within the right cardiac auricle composed of neoplastic epithelioid cells which infiltrated the myocardium and frequently exhibited intracytoplasmic luminae. Cells multifocally exhibited strong cytoplasmic immunoreactivity for Factor VIII-related protein (von Willebrand's factor). CONCLUSIONS: The histological characteristics of this tumor are consistent with a diagnosis of epithelioid hemangioendothelioma, an intermediate-grade vasoformative neoplasm which has to our knowledge not previously been reported in the heart of a non-human species.


Assuntos
Neoplasias Cardíacas/veterinária , Hemangioendotelioma Epitelioide/veterinária , Macaca mulatta , Doenças dos Macacos/patologia , Animais , Átrios do Coração/patologia , Neoplasias Cardíacas/patologia , Hemangioendotelioma Epitelioide/patologia , Masculino
11.
Clin Exp Immunol ; 153(3): 456-62, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18637102

RESUMO

Immunoglobulin A (IgA) glycosylation, recognized as an important pathogenic factor in IgA nephropathy (IgAN), is apparently controlled by the polarity of T helper (Th) cytokine responses. To examine the role of cytokine polarity in IgAN, inbred mice were immunized by intraperitoneal priming with inactivated Sendai virus (SeV) emulsified in either complete Freund's adjuvant (CFA) or incomplete Freund's adjuvant (IFA), which promote Th1- or Th2-immune response, respectively, and then boosted identically twice orally with aqueous suspensions of inactivated virus. Next, some mice were challenged intranasally with infectious SeV. Mice primed with CFA or IFA had equal reductions in nasal viral titre relative to non-immune controls, and equally increased serum levels of SeV-specific IgA antibody. Mice primed with CFA showed higher SeV-specific IgG than those with IFA. Splenocytes from mice primed with IFA produced copious amounts of interleukin (IL)-4 and IL-5, but little interferon-gamma and IL-2; those primed with CFA had reciprocal cytokine recall responses. Total serum IgA and especially SeV-specific IgA from mice primed with IFA showed a selective defect in sialylation and galactosylation. Although the frequency and intensity of glomerular deposits and haematuria did not differ, glomerulonephritis in mice primed with IFA and challenged with infectious virus was more severe than in those given CFA, as judged by serum creatinine level. We conclude that the polarity of T cell cytokines controls the pattern of IgA glycosylation and exerts direct or indirect effects on functional glomerular responses to immune complex deposition.


Assuntos
Citocinas/imunologia , Glomerulonefrite por IGA/imunologia , Imunoglobulina A/imunologia , Vírus Sendai/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adjuvantes Imunológicos , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Adjuvante de Freund , Glicosilação , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lipídeos , Camundongos , Camundongos Endogâmicos BALB C , Líquido da Lavagem Nasal/imunologia , Células Th1/metabolismo , Células Th2/metabolismo
12.
Theriogenology ; 117: 34-39, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29807256

RESUMO

The tolerance of sperm DNA structure to seminal plasma and freezing conditions has both clinical and basic biologic relevance. In this study, fresh (FS) or flash-frozen (FZ) stallion epididymal sperm were exposed (SP+) or unexposed (SP-) to seminal plasma. Sperm were then evaluated to monitor the degree of change in DNA structure following challenge with chemical (dithiothreitol-DTT), oxidative (iron sulfate; FeSO4) or enzymatic (DNase I) potentiators of DNA damage. For sperm not treated with potentiators (controls), there was no effect of SP treatment (SP- vs. SP+) or freezing treatment (FS vs. FZ; non-significant) on measures of any DNA assays (i.e., 8-hydroxy, 2'deoxyguanosine [8OHdG], TUNEL, or sperm chromatin structure [SCSA] assays). Group FZ was more susceptible than Group FS to potentiators of DNA damage. Percent 8OHdG-positive sperm was higher in Group FZ/SP- treated with FeSO4 than all other groups (P < 0.05). Percent TUNEL-positive sperm was similar among FZ/SP- groups treated with DTT, FeSO4, or DNase (non-significant) and was higher in these groups than all other treatments (P < 0.05). Percent COMP-αt was higher following treatment with DNase or DTT, as compared to their respective controls, regardless of prior exposure to SP (P < 0.05). Overall, sperm DNA structure was unaffected by seminal plasma or freezing treatment when samples were not exposed to potentiators of sperm DNA damage; however, marked differences were identified in DNA structure when sperm were challenged with chemical, oxidative or enzymatic treatments. These results highlight the importance of challenging DNA structure prior to analysis. The use of potentiators of DNA damage provided a model to evaluate sperm DNA structure following exposure of sperm to various experimental treatments.


Assuntos
Criopreservação/veterinária , Dano ao DNA , DNA/ultraestrutura , Cavalos , Preservação do Sêmen/veterinária , Sêmen , Animais , Criopreservação/métodos , Desoxirribonuclease I/farmacologia , Ditiotreitol/farmacologia , Marcação In Situ das Extremidades Cortadas , Masculino , Estresse Oxidativo , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Sulfatos/farmacologia
13.
Theriogenology ; 122: 23-29, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30219312

RESUMO

Two experiments were conducted to evaluate the effects of antibiotic-containing extender of on sperm quality and control of bacterial growth. In Experiment 1, ejaculates were diluted in extender containing no antibiotics, potassium penicillin G-amikacin disulfate (PEN-AMIK), ticarcillin disodium-potassium clavulanate (TICAR-CLAV), piperacillin sodium/tazobactam sodium (PIP-TAZ), or meropenem (MERO). In freshly extended semen, only slight differences were detected among some antibiotic treatments for total sperm motility, curvilinear velocity, and viable acrosome-intact sperm (P < 0.05). In cool-stored semen, slight differences were also detected among certain antibiotic treatments for curvilinear velocity and chromatin integrity (P < 0.05). In Experiment 2, ejaculates were diluted in extender and subjected to no bacterial spiking, or inoculated with lower or higher doses of K. pneumoniae or P. aeruginosa. Following cooled storage of semen, colony forming units/ml (CFU/mL) were less in PEN-AMIK (706 ±â€¯244) and MERO (1576 ±â€¯1076) treatment groups than in TICAR-CLAV (4678 ±â€¯1388) or PIP-TAZ (8108 ±â€¯3198) treatment groups (P < 0.05). The CFU/mL were lower in all antibiotic-containing treatment groups than the control group (18478 ±â€¯4374; P < 0.05). The percentage of culture plates containing no bacterial growth in unspiked semen was greater in PEN-AMIK (75%) than PIP-TAZ (15%) or TICAR-CLAV (20%; P < 0.05). The percentages of culture plates containing no bacterial growth in semen spiked with a lower doses of K. pneumoniae or P. aeruginosa were higher in PEN-AMIK (70% and 50%, respectively) then in all other treatment groups (0-40% and 0-15% for K. pneumonia and P. aeruginosa, respectively; P < 0.05); however, complete control of bacterial load was only modest even with PEN-AMIK. In both experiments, freezing and thawing extender prior to use did not have any appreciable detrimental effect on sperm quality or antibiotic efficacy. In summary, all antibiotics tested had minimal effects on measures of sperm quality in fresh or cool-stored semen extenders; however, PEN-AMIK, followed by MERO, yielded the best results in terms of antimicrobial efficacy. None of the antibiotic types controlled bacterial growth, in comparison with the antibiotic-free control group, when extended semen was spiked with a high concentration of Pseudomonas aeruginosa. Cooled storage of extended semen reduced bacterial growth in comparison with freshly extended semen.


Assuntos
Cavalos , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Antibacterianos/farmacologia , Masculino , Sêmen/microbiologia , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos
14.
J Clin Invest ; 102(9): 1758-65, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9802890

RESUMO

Many people who remain persistently seronegative despite frequent HIV exposure have HIV-specific immune responses. The study of these may provide information about mechanisms of natural protective immunity to HIV-1. We describe the specificity of cytotoxic T lymphocyte responses to HIV in seronegative prostitutes in Nairobi who are apparently resistant to HIV infection. These women have had frequent exposure to a range of African HIV-1 variants, primarily clades A, C, and D, for up to 12 yr without becoming infected. Nearly half of them have CTL directed towards epitopes previously defined for B clade virus, which are largely conserved in the A and D clade sequences. Stronger responses are frequently elicited using the A or D clade version of an epitope to stimulate CTL, suggesting that they were originally primed by exposure to these virus strains. CTL responses have been defined to novel epitopes presented by HLA class I molecules associated with resistance to infection in the cohort, HLA-A*6802 and HLA-B18. Estimates using a modified interferon-gamma Elispot assay indicate a circulating frequency of CTL to individual epitopes of between 1:3,200 and 1:50,000. Thus, HIV-specific immune responses-particularly cross-clade CTL activity- may be responsible for protection against persistent HIV infection in these African women.


Assuntos
Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Estudos de Coortes , Sequência Conservada , Epitopos de Linfócito T/química , Feminino , Produtos do Gene gag/imunologia , Protease de HIV/imunologia , Transcriptase Reversa do HIV/imunologia , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Antígeno HLA-B18 , Humanos , Imunidade Inata , Quênia , Peptídeos , Análise de Sequência , Trabalho Sexual , Linfócitos T Citotóxicos/virologia
15.
Theriogenology ; 95: 113-117, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28460664

RESUMO

The effect of flash-freezing storage temperature on stallion sperm DNA has not been evaluated. Commonly, sperm are flash-frozen at various temperatures to preserve sperm DNA prior to analysis. It is unclear whether the temperature at which sperm are frozen and stored may affect the results of DNA assays. In this study, the neutral comet assay was used to evaluate the effect of flash-freezing storage temperature (freezer [-60 °C], dry ice [-78.5 °C], liquid nitrogen [-196 °C]) compared to fresh sperm DNA structure. In addition, intra- and inter-assay and intra- and inter-stallion variabilities were determined. All comet tail measures were higher following any flash-freezing method, as compared to fresh sperm DNA (P < 0.05), with no difference among flash-frozen treatments (P > 0.05). For most comet variables, intra- and inter-assay variabilities were <10%. Intra- and inter-stallion variabilities revealed that comet head length (HL) and width (CW) were less variable as compared to comet tail values, i.e., % comet tail DNA (T-DNA), tail length (TL), tail moment (OTM), and tail migration (TM). Certain comet tail values in fresh (% T-DNA, and OTM) and flash-frozen sperm (OTM, % T-DNA, TL, and TM) were correlated to the Sperm Chromatin Structure Assay (SCSA) variable, COMP-αt. The comet tail measures were negatively correlated to % morphologically normal sperm (P < 0.05) and positively correlated to % abnormal heads and premature germ cells (P < 0.05). Variables COMP-αt and % total sperm motility were not correlated to any morphologic sperm feature in this group of stallions (P > 0.05). While significant differences in the structure of the sperm DNA were identified in the flash-frozen as compared to the fresh sperm DNA with the neutral comet assay, it cannot be assumed that these changes are fertility limiting.


Assuntos
Dano ao DNA , Congelamento , Cavalos , Espermatozoides/citologia , Animais , Ensaio Cometa/veterinária , Criopreservação/veterinária , Masculino , Temperatura
16.
Theriogenology ; 94: 8-14, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28407865

RESUMO

Breeding records were analyzed from 24 Thoroughbred stallions that were subjected to dual-hemisphere breeding (DH), including novice (first-year; NOV; n = 11) and experienced (EXP; n = 13) stallions. Fertility variables included seasonal pregnancy rate, pregnancy rate per cycle, and first-cycle pregnancy rate. In addition, values for book size, total number of covers, distribution of mare type (maiden, foaling, and barren) within a stallion's book, cycles per mare, and mare age were examined. Some data were also categorized by mare type (maiden-M, foaling-F, and barren-B). Five separate analyses of the data were performed. For Analyses 1-3, the effects of hemisphere (northern hemisphere [NH] vs. southern hemisphere [SH]) and breeding order (refers to the first [O1] or second [O2] season within the first year of dual-hemisphere breeding) were examined for all stallions (combined group [CG]), NOV stallions only, and EXP stallions only, respectively. Fertility values were generally higher in the SH than the NH (P < 0.05), whereas book size, total number of covers, and cycles per mare were higher in the NH than the SH (P < 0.05). Book size and total covers were negatively correlated to first cycle pregnancy rate (r = -0.57, r = -0.71, respectively; P < 0.05) for NOV stallions. Pregnancy rate per cycle was also negatively correlated with total covers (r = -0.58; P < 0.05) for NOV stallions. Similar trends were noted for Groups CG and EXP, but the relationship was not as marked as for NOV stallions. The fertility of O1 was generally similar to O2 (P > 0.05). For Analysis 4, fertility of DH breeding seasons was compared to single hemisphere (SIN) breeding seasons within the same 16 stallions and was found to be similar between the two groups (P > 0.05). For Analysis 5, the effect of the number of consecutive DH breeding seasons on fertility was examined and was found to remain unchanged (P > 0.05). In summary, no adverse effects of DH breeding on fertility were detected. Fertility was higher when stallions were bred in the SH, as compared to the NH. Potential reasons for higher fertility achieved in the SH were smaller book sizes and better mare reproductive quality.


Assuntos
Cruzamento/métodos , Fertilidade , Cavalos/fisiologia , Estações do Ano , Animais , Feminino , Geografia , Masculino , Fotoperíodo , Gravidez , Taxa de Gravidez
17.
Theriogenology ; 86(6): 1399-1402, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27268295

RESUMO

Hemospermia can occur consistently or intermittently in stallion ejaculates and may cause a reduction in the fertility of the affected ejaculate. It is unknown what amount of blood in an ejaculate leads to subfertility. This study investigated the effect of higher and lower levels of hemospermia (50% and 5%, respectively) on fertility using 24 reproductively normal mares inseminated over three consecutive estrous cycles with fresh extended semen. Mares inseminated with a 5% blood-contaminated ejaculate became pregnant at the same rate (75% per cycle; 18 of 24) as the mares inseminated with blood-free (control) semen (75% per cycle; 18 of 24). The ejaculates containing 50% blood were sterile (0% per cycle, 0 of 24). We concluded that it is the amount of blood, not the mere presence of blood, in an ejaculate that impacts fertility.


Assuntos
Hemospermia/veterinária , Infertilidade/veterinária , Animais , Ciclo Estral , Feminino , Hemospermia/complicações , Hemospermia/fisiopatologia , Cavalos , Infertilidade/etiologia , Inseminação Artificial/veterinária , Masculino , Gravidez , Ultrassonografia Pré-Natal/veterinária
18.
Curr Top Microbiol Immunol ; 241: 181-213, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10087662

RESUMO

Studies in both humans and animals demonstrate that H. pylori is capable of illiciting an innate response that in part is regulated by the genetic makeup of the host. These innate responses includes stimulating immune effector mechanisms at the cellular and biochemical level resulting in the influx of neutrophils into the lamina propria and have even been shown to modify gastric acid secretion. The availability of good animal models of chronic Helicobacter infection has also allowed investigators to begin to examine how the adaptive host immune response prevents and/or exacerbates Helicobacter-induced gastroduodenal disease. The experimental H. felis/mouse model has been utilized by a number of laboratories to investigate mechanisms of host defense against chronic Helicobacter infection. This model and the more recently developed H. pylori rodent model has not only allowed investigators to confirm the feasibility of immunotherapy to prevent and/or cure Helicobacter infection but also to begin to examine how the host immune response prevents and/or exacerbates Helicobacter-induced gastroduodenal disease. Based on these studies a hypothesis is emerging that suggests that protection and/or cure from Helicobacter infection is mediated primarily by an upregulated cellular immune response which may act via an antibody independent mechanism. Paradoxically, following natural infection with H. pylori, a component of the cellular immune response also promotes chronic gastric inflammation without clearance of the organism. The recent development of reliable and reproducible H. pylori/rodent models of disease and the availability of numerous inbred strains, transgenic and knockout animals, will allow investigators to continue to explore the role the host cellular and humoral immune response plays in promoting or preventing this infection.


Assuntos
Vacinas Bacterianas/imunologia , Gastroenteropatias/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Oral , Animais , Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Vacinas Bacterianas/administração & dosagem , Ensaios Clínicos como Assunto , Citocinas/metabolismo , Modelos Animais de Doenças , Ácido Gástrico/metabolismo , Mucosa Gástrica/imunologia , Gastroenteropatias/microbiologia , Gastroenteropatias/terapia , Predisposição Genética para Doença , Infecções por Helicobacter/terapia , Humanos , Imunidade Ativa , Imunidade Celular , Imunidade Inata , Imunidade nas Mucosas/imunologia , Camundongos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
19.
Theriogenology ; 63(6): 1584-91, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15763103

RESUMO

The relationship between seminal plasma level (0, 10, or 20%) and extender type [Kenney type (EZ-Mixin-CST) or Kenney-modified Tyrodes-KMT] to the susceptibility of sperm DNA to denaturation and sperm motility measures were investigated in cooled (5 degrees C) stallion sperm. Three ejaculates from each of three fertile stallions were collected in an artificial vagina and processed as follows: diluted one part uncentrifuged semen with four parts of extender to a final concentration of 20% seminal plasma in either CST or KMT (20% CST; 20% KMT); diluted to a final concentration of 25 million sperm/mL in either CST or KMT (10% CST; 10% KMT); centrifuged to remove virtually all seminal plasma and resuspended in either CST or KMT (0% CST-Cent; 0% KMT-Cent); centrifuged semen to remove virtually all seminal plasma and resuspended with previously filtered seminal plasma from the same stallion in either CST or KMT to a final concentration of 20% seminal plasma (20% CST-Cent; 20% KMT-Cent). Sperm motion characteristics were determined by CASA and DNA integrity (%COMP, percent of cells outside the main population) evaluated by the Sperm Chromatin Structure Assay prior to cooling, and after 24 and 48 h cooled-storage at 5 degrees C. After 48 h of storage at 5 degrees C, extenders with 0% seminal plasma (0% CST-Cent, 0% KMT-Cent) maintained highest quality DNA (P < 0.05), but 0% KMT-Cent maintained higher velocity measures (P < 0.05) than 0% CST-Cent. Total sperm motility was highest (P < 0.05) in 0% CST-Cent, 0% KMT-Cent, 10% CST, 20% CST-Cent, and 20% CST compared to the other treatment groups. Progressive sperm motility was highest (P < 0.05) after 48 h of storage in the treatment with 10% seminal plasma in Kenney extender (10% CST), despite a reduction in DNA integrity. Regardless of extender type, addition of 20% seminal plasma following centrifugation resulted in almost a two-fold increase in %COMP(alpha t), even though one of the treatments (20% CST-Cent) maintained total and progressive motility similar to treatments with no seminal plasma, suggesting that sperm motility and DNA integrity may respond independently to environmental conditions. Overall, better quality sperm features (motility and DNA) were maintained in sperm from which seminal plasma was removed followed by resuspension in either Kenney extender or modified Kenney Tyrodes-type extender.


Assuntos
DNA/análise , Cavalos , Sêmen/fisiologia , Motilidade dos Espermatozoides , Espermatozoides/química , Animais , DNA/química , Masculino , Desnaturação de Ácido Nucleico , Soluções , Espermatozoides/fisiologia
20.
Theriogenology ; 84(5): 833-7, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26104544

RESUMO

Unilateral orchiectomy (UO) may interfere with thermoregulation of the remaining testis caused by inflammation surrounding the incision site, thus altering normal spermatogenesis and consequently sperm quality. Two measures of sperm DNA quality (neutral comet assay and the sperm chromatin structure assay [SCSA]) were compared before UO (0 days) and at 14, 30, and 60 days after UO to determine whether sperm DNA changed after a mild testis stress (i.e., UO). The percent DNA in the comet tail was higher at 14 and 60 days compared to 0 days (P < 0.05) after UO. All other comet tail measures (i.e., length, moment, migration) were higher at all time periods after UO compared to 0 days (P < 0.05). Two SCSA measures (mean-αt, mode-αt) increased at 14 days after UO (P < 0.05), whereas two measures (SD-αt and COMP-αt) did not change. This study identified a decrease in sperm DNA quality using both the neutral comet assay and the SCSA, which was not identified using traditional measures of sperm quality.


Assuntos
Cavalos , Orquiectomia/veterinária , Animais , Cromatina/ultraestrutura , Ensaio Cometa/veterinária , Dano ao DNA , Masculino , Orquiectomia/efeitos adversos , Análise do Sêmen/métodos , Análise do Sêmen/veterinária
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