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1.
J Dairy Sci ; 100(3): 2068-2079, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28088405

RESUMO

The objectives of this study were to investigate colostrum feeding practices and colostrum quality on commercial grassland-based dairy farms, and to identify factors associated with colostrum quality that could help inform the development of colostrum management protocols. Over 1 yr, background information associated with dairy calvings and colostrum management practices were recorded on 21 commercial dairy farms. Colostrum samples (n = 1,239) were analyzed for fat, protein, lactose, and IgG concentration. A subset was analyzed for somatic cell count and total viable bacteria count. Factors associated with nutritional and IgG concentrations were determined using both univariate and multivariate models. This study found that 51% of calves were administered their first feed of colostrum via esophageal tube, and the majority of calves (80%) were fed >2 L of colostrum at their first feed (mean = 2.9 L, SD = 0.79), at a mean time of 3.2 h (SD 4.36) after birth, but this ranged across farms. The mean colostral fat, protein, and lactose percentages and IgG concentrations were 6.4%, 14%, 2.7%, and 55 mg/mL, respectively. The mean somatic cell count and total viable count were 6.3 log10 and 6.1 log10, respectively. Overall, 44% of colostrum samples contained <50 mg/mL IgG, and almost 81% were in excess of industry guidelines (<100,000 cfu/mL) for bacterial contamination. In the multivariate model, IgG concentration was associated with parity and time from parturition to colostrum collection. The nutritional properties of colostrum were associated with parity, prepartum vaccination, season of calving, and dry cow nutrition. The large variation in colostrum quality found in the current study highlights the importance of routine colostrum testing, and now that factors associated with lower-quality colostrum on grassland-based dairy farms have been identified, producers and advisers are better informed and able to develop risk-based colostrum management protocols.


Assuntos
Colostro/metabolismo , Lactose , Animais , Animais Recém-Nascidos , Bovinos , Feminino , Pradaria , Imunoglobulina G/metabolismo , Irlanda do Norte
2.
J Dairy Sci ; 100(1): 357-370, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27865490

RESUMO

The objectives were to evaluate the effect of (1) supplementing concentrates to multiparous Holstein cows during the dry period on colostral and milk immunoglobulin G (IgG) concentration; and (2) feeding calves colostrum at either 5 or 10% of their body weight (BW) on passive transfer of immunity, health, and performance. Holstein multiparous cows (n=37) were assigned to 1 of 2 nutritional treatments during an 8-wk dry period: (1) offered ad libitum grass silage only (GS) or (2) offered ad libitum access to the same grass silage plus concentrate [total mixed ration in a 75:25 dry matter (DM) ratio], providing a mean concentrate DM intake of 3.0kg/cow per day (GSC). Both treatment groups were offered identical levels of mineral and vitamin supplementation. Calves from these cows were weighed immediately after birth and fed either 5% (5BW) or 10% (10BW) of their BW in colostrum from their own dams within 2.5h of birth. Calves in the 10BW group received their second feed of colostrum from first-milking colostrum. Concentrate supplementation during the dry period had no effect on colostral IgG concentration, first-milking IgG yield, or fat, protein, and lactose contents. However, cows in GSC produced a greater mean milk yield over the first 8 milkings compared with cows in the GS group. Concentrate supplementation had no effect on calf BW or BW gain, serum IgG, or apparent efficiency of absorption (AEA) at 24h after birth. However, offspring from the GSC group had fewer cases of enteritis during the first 56d of life compared with offspring from the GS group. Calves in the 10BW group had greater mean serum IgG concentration for the first 3d following birth; however, at 24h after birth, we observed no treatment effect on AEA. The rate of enteritis was greater for calves in the 5BW treatment compared with 10BW. The colostrum-feeding regimen had no effect on BW gain or on the incidence of pneumonia among calf treatment groups. In conclusion, concentrate supplementation regimens offered during the dry period had a positive effect on colostrum yield, and offspring from the GSC group had a reduced rate of enteritis. Feeding 10% of BW of colostrum versus 5% of BW resulted in a greater serum IgG concentration for the first 3d postpartum, and 10BW calves had a reduced rate of enteritis. Overall, to achieve successful passive transfer, decrease the rate of enteritis, and increase efficiency in the dairy calf, we recommend that dairy calves be fed 10% of their BW in colostrum as soon as possible after birth.


Assuntos
Animais Recém-Nascidos , Colostro/imunologia , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Imunização Passiva , Leite/metabolismo
3.
J Dairy Sci ; 100(6): 4457-4474, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28342599

RESUMO

Because negative energy balance (EB) contributes to transition-period immune dysfunction in dairy cows, dietary management strategies should aim to minimize negative EB during this time. Prepartum diets that oversupply energy may exacerbate negative EB in early lactation, with detrimental effects on immune function. However, with lower body condition score (BCS) cows, it has been shown that offering concentrates in addition to a grass silage-based diet when confined during an 8-wk dry period resulted in increased neutrophil function in early lactation. The aim of this study was to examine if similar benefits occur when concentrate feeding was restricted to a 4-wk period prepartum. Twenty-six multiparous and 22 primiparous Holstein-Friesian cows were offered ad libitum access to medium-quality grass silage until 28 d before their predicted calving dates (actual mean of 32 d prepartum; standard deviation = 6.4). At this time multiparous cows had a mean BCS of 2.9 (standard deviation = 0.12) and primiparous cows a mean BCS of 3.0 (standard deviation = 0.14) on a 1 to 5 scale. Cows were then allocated in a balanced manner to 1 of 2 treatments (13 multiparous cows and 11 primiparous cows on each treatment): silage only (SO) or silage plus concentrates (S+C) until calving. Cows on SO were offered the same grass silage ad libitum. Cows on S+C were offered an ad libitum mixed ration of the same grass silage and additional concentrates in a 60:40 dry matter (DM) ratio, which provided a mean concentrate DM intake (DMI) of 4.5 kg/cow per d. After calving, all cows were offered a common mixed ration (grass silage and concentrates, 40:60 DM ratio) for 70 d postpartum. Offering concentrates in addition to grass silage during the 4 wk prepartum increased prepartum DMI (12.0 versus 10.1 kg/cow per d), EB (+40.0 versus +10.6 MJ/cow per d), and body weight (BW; 640 versus 628 kg), and tended to increase BCS (3.02 versus 2.97). However, postpartum DMI, milk yield, milk composition, BW change, BCS change, serum nonesterified fatty acid, and ß-hydroxybutryrate concentrations, health, and corpus luteum measures were unaffected by treatment. The in vitro assays of neutrophil phagocytosis, neutrophil oxidative burst, and interferon gamma production, conducted on blood samples obtained at d 14 prepartum and d 3, 7, 14, and 21 postpartum, were unaffected by treatment. Primiparous cows had higher phagocytic fluorescence intensity at d 14 prepartum and d 3 and 7 postpartum; a higher percentage of neutrophils undergoing oxidative burst at d 3, 7, and 21 postpartum; and a higher oxidative burst fluorescence intensity at d 14 prepartum and d 7, 14, and 21 postpartum compared with multiparous cows. This suggests that neutrophil function of primiparous cows was less sensitive to the changes occurring during the transition period than that of multiparous cows. In conclusion, offering concentrates during the 4-wk period prepartum had no effect on postpartum DMI, milk yield, body tissue mobilization, EB, measures of neutrophil or lymphocyte function, health, or corpus luteum activity.


Assuntos
Ração Animal , Ingestão de Energia , Metabolismo Energético , Lactação/fisiologia , Neutrófilos/fisiologia , Paridade , Poaceae , Silagem , Animais , Bovinos , Dieta , Feminino , Leite , Período Pós-Parto , Gravidez , Fatores de Tempo
4.
Parasite Immunol ; 38(7): 387-402, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27108767

RESUMO

Bovine tuberculosis (BTB), caused by Mycobacterium bovis, has an annual incidence in cattle of 0.5% in the Republic of Ireland and 4.7% in the UK, despite long-standing eradication programmes being in place. Failure to achieve complete eradication is multifactorial, but the limitations of diagnostic tests are significant complicating factors. Previously, we have demonstrated that Fasciola hepatica infection, highly prevalent in these areas, induced reduced sensitivity of the standard diagnostic tests for BTB in animals co-infected with F. hepatica and M. bovis. This was accompanied by a reduced M. bovis-specific Th1 immune response. We hypothesized that these changes in co-infected animals would be accompanied by enhanced growth of M. bovis. However, we show here that mycobacterial burden in cattle is reduced in animals co-infected with F. hepatica. Furthermore, we demonstrate a lower mycobacterial recovery and uptake in blood monocyte-derived macrophages (MDM) from F. hepatica-infected cattle which is associated with suppression of pro-inflammatory cytokines and a switch to alternative activation of macrophages. However, the cell surface expression of TLR2 and CD14 in MDM from F. hepatica-infected cattle is increased. These findings reflecting the bystander effect of helminth-induced downregulation of pro-inflammatory responses provide insights to understand host-pathogen interactions in co-infection.


Assuntos
Citocinas/imunologia , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Mycobacterium bovis/crescimento & desenvolvimento , Tuberculose Bovina/microbiologia , Animais , Bovinos , Coinfecção/imunologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Citocinas/genética , Fasciolíase/parasitologia , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Macrófagos/microbiologia , Mycobacterium bovis/fisiologia , Tuberculose Bovina/imunologia
5.
J Dairy Sci ; 99(9): 7102-7122, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27394939

RESUMO

When cows with a "higher" body condition score (BCS) are oversupplied with energy during the dry period, postpartum energy balance is normally reduced, which can have a detrimental effect on immune competence and increase the infectious disease risk. However, within grassland-based systems higher yielding cows frequently have a low BCS at drying off. The effects on performance, health, and metabolic and immune functions of providing additional energy to cows with low BCS during the dry period is less certain. To address this uncertainty, 53 multiparous Holstein-Friesian cows (mean BCS of 2.5; 1-5 scale) were allocated to 1 of 2 treatments at dry-off: silage only or silage plus concentrates. Cows on the silage-only treatment were offered ad libitum access to medium-quality grass silage. Cows on the silage-plus-concentrate treatment were offered ad libitum access to a mixed ration comprising the same grass silage plus concentrates [in a 75:25 dry matter (DM) ratio], which provided a mean concentrate DM intake of 3.0kg/cow per day. Postpartum, cows were offered a common mixed ration comprising grass silage and concentrates (in a 40:60 DM ratio) for a 70-d period. Offering concentrates during the dry period increased DM intake, tended to increase energy balance, and increased body weight (BW) and BCS gain prepartum. Offering concentrates during the dry period increased BW and BCS loss postpartum and tended to increase milk fat percentage and serum nonesterified fatty acid concentration, but it did not affect postpartum DM intake, energy balance, and milk yield. Although the percentage of phagocytosis-positive neutrophils did not differ, neutrophils from cows on the silage-plus-concentrate treatment had higher phagocytic fluorescence intensity at 1 and 2 wk postpartum and higher phagocytic index at 1 wk postpartum. Serum haptoglobin concentrations and IFN-γ production by pokeweed mitogen stimulated whole blood culture were unaffected by treatment, although haptoglobin concentrations increased and IFN-γ production decreased peripartum. Offering concentrates during the dry period increased the incidence of lameness postpartum, although other health and fertility parameters were unaffected. In conclusion, supplementing low BCS cows with concentrates during the dry period had no effect on performance and fertility and resulted in a higher neutrophil phagocytic index at 1 wk postpartum and an increased incidence of lameness compared with offering cows a grass silage-only diet prepartum.


Assuntos
Poaceae , Silagem , Animais , Bovinos , Dieta/veterinária , Feminino , Fertilidade , Lactação , Leite/metabolismo
6.
Avian Pathol ; 44(6): 436-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26286674

RESUMO

The development of an indirect enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of Group B chicken astrovirus (CAstV) infections is described. The test was based on the use of an affinity-purified capsid antigen, specific to CAstV isolate 11672, produced as a glutathione-S-transferase N-terminal fusion protein by a recombinant baculovirus. Strongly positive ELISA signals were elicited against experimentally produced antisera raised to CAstVs from Group B (subgroups i and ii) but were negative for antisera raised to a Group A CAstV. Using a panel of 240 selected serum samples, 99% agreement was observed when the results obtained by ELISA were compared to those from an indirect immunofluorescence test for CAstV 11672. The ELISA test was applied to 68 serum sets comprising 1864 samples, which were obtained from parent and grandparent flocks originating mainly in the UK. Of the 52 sets containing ELISA-positive samples, 24 sets had >75% samples positive and nine sets had <25% samples positive and were regarded as having high and low seropositivities, respectively. Of the 1864 serum samples tested 1090 (58.5%) were ELISA positive and of these, 234 sera (21.5%) produced strongly positive signals, whereas moderately positive and weakly positive signals were produced by 562 (51.5%) and 294 (27%) sera. When used for flock screening purposes, this ELISA test can be used to (i) investigate the occurrence of first-time CAstV infections of parent flocks during lay and the possible adverse effects caused by vertically transmitted CAstV infections on broiler hatchability and performance and (ii) diagnose Group B CAstV infections within specific pathogen free flocks.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Infecções por Astroviridae/veterinária , Avastrovirus/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Aves Domésticas/diagnóstico , Animais , Infecções por Astroviridae/diagnóstico , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/virologia , Avastrovirus/isolamento & purificação , Baculoviridae , Proteínas do Capsídeo/imunologia , Galinhas , Soros Imunes , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Proteínas Recombinantes de Fusão , Organismos Livres de Patógenos Específicos
7.
Environ Monit Assess ; 187(8): 503, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26169979

RESUMO

Recent research indicates that riparian zones have the potential to contribute significant amounts of greenhouse gases (GHG: N2O, CO2, CH4) to the atmosphere. Yet, the short-term spatial and temporal variability in GHG emission in these systems is poorly understood. Using two transects of three static chambers at two North Carolina agricultural riparian zones (one restored, one unrestored), we show that estimates of the average GHG flux at the site scale can vary by one order of magnitude depending on whether the mean or the median is used as a measure of central tendency. Because the median tends to mute the effect of outlier points (hot spots and hot moments), we propose that both must be reported or that other more advanced spatial averaging techniques (e.g., kriging, area-weighted average) should be used to estimate GHG fluxes at the site scale. Results also indicate that short-term temporal variability in GHG fluxes (a few days) under seemingly constant temperature and hydrological conditions can be as large as spatial variability at the site scale, suggesting that the scientific community should rethink sampling protocols for GHG at the soil-atmosphere interface to include repeated measures over short periods of time at select chambers to estimate GHG emissions in the field. Although recent advances in technology provide tools to address these challenges, their cost is often too high for widespread implementation. Until technology improves, sampling design strategies will need to be carefully considered to balance cost, time, and spatial and temporal representativeness of measurements.


Assuntos
Agricultura/estatística & dados numéricos , Dióxido de Carbono/análise , Monitoramento Ambiental/métodos , Metano/análise , Óxido Nitroso/análise , Gases/análise , Efeito Estufa , North Carolina , Rios , Solo
8.
Int J Sports Med ; 35(5): 363-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24048912

RESUMO

Matrix metalloproteinase-9 is a proteolytic enzyme capable of degrading proteins of the muscle extracellular matrix. Systemic levels of MMP-9 or its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), have the potential to serve as blood markers of exercise-induced muscle damage. The purpose of this study was to determine if an eccentrically-dominated task, downhill running (DHR), produces changes in plasma MMP-9 or TIMP-1 and examine the relationship between MMP-9/TIMP-1 levels and indirect indicators of muscle damage. Subjects were sedentary (SED, n=12) or had a history of concentrically-biased training (CON, n=9). MMP-9 and TIMP-1 were measured before (Pre-Ex), immediately after (Post-Ex), and 1-, 2-, 4-, and 7-days post-DHR (-10°), and compared to discomfort ratings, creatine kinase activity and strength loss. At 1-day Post-Ex, discomfort increased (5.6 ± 7.8 to 45.5 ± 19.9 mm; 0-100 mm scale), strength decreased (-6.9 ± 1.6%) and CK increased (162.9 ± 177.2%). MMP-9 was modestly but significantly increased at Post-Ex in both CONC and SED (32.7 ± 33.6%) and at 4-days in SED (66.9 ± 88.1%), Individual responses were variable, however. There were no correlations between MMPs and discomfort ratings, plasma CK or strength. While plasma MMP-9 changes may be detectable in the systemic circulation after DHR, they are small and do not correspond to other markers of damage.


Assuntos
Metaloproteinase 9 da Matriz/sangue , Músculo Esquelético/lesões , Corrida/fisiologia , Inibidor Tecidual de Metaloproteinase-1/sangue , Adulto , Biomarcadores/sangue , Creatina Quinase/sangue , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Força Muscular/fisiologia , Adulto Jovem
9.
J Intern Med ; 273(2): 114-27, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23216836

RESUMO

In this review we summarize the current understanding of signal transduction downstream of vascular endothelial growth factor A (VEGFA) and its receptor VEGFR2, and the relationship between these signal transduction pathways and the hallmark responses of VEGFA, angiogenesis and vascular permeability. These physiological responses involve a number of effectors, including extracellular signal-regulated kinases (ERKs), Src, phosphoinositide 3 kinase (PI3K)/Akt, focal adhesion kinase (FAK), Rho family GTPases, endothelial NO and p38 mitogen-activated protein kinase (MAPK). Several of these factors are involved in the regulation of both angiogenesis and vascular permeability. Tumour angiogenesis primarily relies on VEGFA-driven responses, which to a large extent result in a dysfunctional vasculature. The reason for this remains unclear, although it appears that certain aspects of the VEGFA-stimulated angiogenic milieu (high level of microvascular density and permeability) promote tumour expansion. The high degree of redundancy and complexity of VEGFA-driven tumour angiogenesis may explain why tumours commonly develop resistance to anti-angiogenic therapy targeting VEGFA signal transduction.


Assuntos
Neoplasias/irrigação sanguínea , Neovascularização Patológica/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Permeabilidade Capilar , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Avian Pathol ; 42(5): 434-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24066895

RESUMO

Chicken astroviruses (CAstVs) have been characterized recently. Due to their relatively poor growth in cell culture, virus-specific antigens are not readily available for the development of diagnostic reagents and vaccines. For this purpose two capsid protein antigens, specified by the 11672 isolate of CAstV, were produced in insect cells following infection with recombinant baculoviruses. The GST-11672 capsid protein, a fusion protein comprising the capsid protein and glutathione-S-transferase (GST) as an N-terminal affinity tag, and the 11672 capsid protein alone were detected by western blotting as proteins of ~100 and 70 kDa, respectively. Immunization with the affinity-purified GST-11672 capsid protein produced a polyclonal rabbit antiserum, which reacted by indirect immunofluorescence with Group B CAstVs but which showed no reactivity with the Group A CAstV isolate, 612. When used as part of an immunoperoxidase-based immunohistochemical procedure, this rabbit antiserum facilitated the detection of CAstV antigen in formalin-fixed, paraffin-embedded kidney tissue at the sites of histopathology characteristic of nephritis. Although further evaluation with sera from commercial chickens is required, a prototype indirect antibody-detecting enzyme-linked immunosorbent assay (ELISA) based on affinity-purified GST-11672 capsid protein as coating antigen demonstrated considerable potential with low ELISA absorbance values being generated with sera from specific pathogen free (SPF) chickens, and high absorbance values being generated with serum samples from experimentally infected chickens. Immunization experiments of SPF chickens showed that, when administered as mixtures with oil adjuvant, crude cell lysates containing the GST-11672 capsid protein or the 11672 capsid protein elicited virus-specific antibody responses that were detectable by indirect immunofluorescence and by virus neutralization assays.


Assuntos
Infecções por Astroviridae/veterinária , Avastrovirus/imunologia , Proteínas do Capsídeo/metabolismo , Galinhas , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Animais , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Especificidade de Anticorpos , Antígenos Virais/genética , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/prevenção & controle , Avastrovirus/genética , Baculoviridae/genética , Baculoviridae/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Soros Imunes/imunologia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/imunologia , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Células Sf9 , Organismos Livres de Patógenos Específicos , Spodoptera
11.
Nat Genet ; 4(4): 426-31, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7691356

RESUMO

In the human CFTR only the rare exon 4- splice variant is conserved in mice. We have discovered two novel murine variants, exon 5- and exon 11b+. The exon 5- variant represents up to 40% of mRNA in all CFTR-expressing tissues and leaves the reading frame intact. The exon 11b+ variant inserts a novel exon between exons 11 and 12 with expression restricted to the testis. Two variants of 11b have been found and both introduce premature stop codons. When we expressed human CFTR variants lacking either exon 5 or exon 9 in HeLa cells, they failed to generate cAMP-mediated chloride transport, due to defective intracellular processing. The lack of conservation of splice variants between species and the inability of the more abundant splice variants to generate protein that is correctly processed argue against a physiological role and may simply represent aberrant splicing that is tolerated by the cell and organism.


Assuntos
Processamento Alternativo , Canais de Cloreto/genética , Fibrose Cística/genética , Variação Genética , Proteínas de Membrana/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência Conservada , Regulador de Condutância Transmembrana em Fibrose Cística , Éxons , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , Especificidade de Órgãos , Reação em Cadeia da Polimerase , Mapeamento por Restrição
12.
Diabetologia ; 55(8): 2092-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22696036

RESUMO

Overexpression of c-Kit has recently been shown to ameliorate beta cell function by increasing the beta cell mass and insulin secretion, thus counteracting the deleterious effects of a high-fat diet on glucose homeostasis. The c-Kit-dependent effects are due to enhanced Akt activity that phosphorylates and inhibits glycogen synthase kinase 3ß (GSK3ß), thereby increasing the expression of numerous genes that promote insulin production and cell proliferation. Regulating the c-Kit/Akt/GSK3ß pathway may provide novel means for improving beta cell function in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Células Secretoras de Insulina/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Proliferação de Células , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica , Glicogênio Sintase Quinase 3 beta , Humanos , Camundongos , Camundongos Transgênicos , Transdução de Sinais
13.
Int J Androl ; 35(1): 25-40, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21651570

RESUMO

Testosterone synthesis depends on normal Leydig cell (LC) development, but the mechanisms controlling this development remain unclear. We recently demonstrated that androgen receptor (AR) ablation from a proportion of testicular peritubular myoid cells (PTM-ARKO) did not affect LC number, but resulted in compensated LC failure. The current study extends these investigations, demonstrating that PTM AR signalling is important for normal development, ultrastructure and function of adult LCs. Notably, mRNAs for LC markers [e.g. steroidogenic factor 1 (Nr5a1), insulin-like growth factor (Igf-1) and insulin-like factor 3 (Insl3)] were significantly reduced in adult PTM-ARKOs, but not all LCs were similarly affected. Two LC sub-populations were identified, one apparently 'normal' sub-population that expressed adult LC markers and steroidogenic enzymes as in controls, and another 'abnormal' sub-population that had arrested development and only weakly expressed INSL3, luteinizing hormone receptor, and several steroidogenic enzymes. Furthermore, unlike 'normal' LCs in PTM-ARKOs, the 'abnormal' LCs did not involute as expected in response to exogenous testosterone. Differential function of these LC sub-populations is likely to mean that the 'normal' LCs work harder to compensate for the 'abnormal' LCs to maintain normal serum testosterone. These findings reveal new paracrine mechanisms underlying adult LC development, which can be further investigated using PTM-ARKOs.


Assuntos
Diferenciação Celular , Células Intersticiais do Testículo/citologia , Receptores Androgênicos/metabolismo , Transdução de Sinais , Animais , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos
14.
Int J Androl ; 35(2): 211-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22372740

RESUMO

The 'International Network for Young Researchers in Male Fertility' has now turned 6 years old and offers a platform that stimulates scientific exchange as well as the development of international cooperation for young researchers. We report on our scope and the exciting achievements, amongst others, the continually increasing number of participants and the growing success of our annual meetings.


Assuntos
Pesquisa Biomédica , Fertilidade , Sociedades Científicas , Testículo , Educação , Humanos , Infertilidade Masculina , Cooperação Internacional , Masculino , Pesquisadores
15.
Avian Pathol ; 41(2): 151-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22515534

RESUMO

The complete capsid gene sequences of 24 chicken astroviruses (CAstVs), collected in the UK, Germany, the Netherlands and South Africa from the 1980s to 2008, were determined and compared with that of a US CAstV (UGA-2006). Pairwise comparisons and phylogenetic analysis demonstrated the existence of two major capsid groups, designated A and B, which shared 38 to 40% amino acid identity. CAstVs from groups A and B shared capsid protein identities ranging from 26 to 38% with other avian astroviruses. The group A CAstVs comprised three subgroups, which displayed inter-subgroup identities ranging from 77 to 82%, while group B comprised two clearly separated subgroups, Bi and Bii, which displayed intra-subgroup identities of 97 to 99% and 94 to 99%, respectively, and shared inter-subgroup identities of 84 to 85%. Phylogenetic analyses performed with contiguous open reading frame 1b (polymerase) and open reading frame 2 (capsid) CAstV sequences showed that CAstVs from capsid subgroup Bi had polymerase genes that differed from those possessed by CAstVs belonging to group A and subgroup Bii. The N-terminal capsid regions (residues 1 to 415) were more conserved than the C-terminal regions, with the C-terminal regions of the subgroup Bi and Bii CAstVs sharing 76 to 78% amino acid identity, while the C-terminal regions of the A subgroups displayed identities less than 75%. CAstVs representative of both capsid groups and more than one subgroup were detected within the same broiler flock. The high level of capsid sequence diversity observed in this study has important implications for both the control and diagnosis of CAstV infections.


Assuntos
Avastrovirus/genética , Proteínas do Capsídeo/genética , Galinhas/virologia , Variação Genética , Filogenia , Sequência de Aminoácidos , Animais , Avastrovirus/classificação , Sequência de Bases , Análise por Conglomerados , Primers do DNA/genética , Europa (Continente) , Modelos Genéticos , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , África do Sul , Especificidade da Espécie , Estados Unidos
16.
J Fish Dis ; 35(10): 711-24, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22804799

RESUMO

The development and the application of a quantitative duplex real-time PCR for the detection of Neoparamoeba perurans and the elongation factor α 1 gene (ELF) of Atlantic salmon, Salmo salar L., and rainbow trout, Oncorhynchus mykiss (Walbaum), are described. A set of primers and probe was designed to amplify a 139-bp fragment specific to the N. perurans 18S rRNA gene. The test was shown to be very sensitive, being able to detect as little as 13.4 DNA copies per µL corresponding to 0.15 fg of template DNA. In addition, the reaction that detected N. perurans was found to have a high degree of repeatability and reproducibility, to have a linear dynamic range (R(2 ) = 0.999) extending over 5 log(10) dilutions and to have a high efficiency (104%). The assay was applied to DNA samples extracted from 48 formalin-fixed, paraffin-embedded (FFPE) salmon gill tissues showing varying degrees of gill histopathology and amoebic gill disease (AGD)-type histopathology ranging from absent to severe (each scored 0-3). Neoparamoeba perurans DNA was detected in all the blocks where AGD-type histopathology was diagnosed microscopically and in 43.6% of the blocks showing signs of gill pathology. The association between parasitic load and gill histopathology and AGD-type histopathology severity was also investigated. This study also describes the development and the application of a second real-time PCR for the generic detection of Neoparamoeba spp., Page, 1987. A set of primers and probe conserved among the Neoparamoeba spp. was designed to amplify a 150-bp fragment within the 18S rRNA gene. Applied to N. perurans-negative gill tissues, the method was used to exclude the presence of other Neoparamoeba spp. in those blocks where gill pathology was observed microscopically.


Assuntos
Amebíase/veterinária , Amebozoários/genética , Doenças dos Peixes/diagnóstico , Brânquias/parasitologia , Oncorhynchus mykiss/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Salmo salar/parasitologia , Amebíase/diagnóstico , Animais , Oncorhynchus mykiss/genética , Inclusão em Parafina , Fator 1 de Elongação de Peptídeos/genética , RNA Ribossômico 18S/genética , Reprodutibilidade dos Testes , Salmo salar/genética , Sensibilidade e Especificidade
17.
Arch Virol ; 156(12): 2157-62, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21947503

RESUMO

The production, preliminary characterisation and applications of monoclonal antibodies (mAbs) against two novel swine bocaviruses isolated in cell culture from swine in Northern Ireland are described. Of the 17 stable final clones produced, four were characterised. All were of the IgG2a isotype and showed no cross-reactivity with either bocavirus strain. Partial neutralisation was observed with PBoV4 mAbs and homologous virus. The two mAbs selected for use in antigen-detecting ELISAs were successful in highlighting those fractions containing infectious virus within sucrose gradients. This is the first report of the production of specific reagents that will prove useful in the study of the biology of these viruses and swine bocavirus-associated diseases.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Antivirais/biossíntese , Bocavirus/imunologia , Bocavirus/isolamento & purificação , Sus scrofa/virologia , Animais , Antígenos Virais/análise , Bocavirus/patogenicidade , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Irlanda do Norte , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Suínos , Doenças dos Suínos/virologia
18.
Avian Pathol ; 40(3): 249-59, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21711184

RESUMO

The capsid gene sequences of 25 avian nephritis viruses (ANVs), collected in the UK, Germany and Belgium from the 1980s to 2008, were determined and compared with those of serotype 1 (ANV-1) and serotype 2 (ANV-2) ANV isolates. Amino acid identities as low as 51% were determined. Pairwise comparisons supported by phylogenetic analysis identified six ANVs, including ANV-1 and ANV-2, which shared<80% amino acid identities with one another, and which were selected to be representative of six groups. The ANVs were not distributed according to geographical location or year of sampling, and the detection of ANVs from five different groups in 11 samples sourced from six flocks belonging to the same UK organization within a 4-month period indicated that sequence-diverse ANVs were co-circulating. Amino acid alignments demonstrated the existence of variable regions throughout the capsid protein, nine of which were selected for detailed comparisons. With most ANVs, the variable region sequences were similar to those of one of the six representative ANVs, but some ANV capsids displayed novel variable region profiles, in which variable regions that were characteristic of more than one representative ANV were present. Phylogenetic analysis based on C-terminal sequences of approximately 260 amino acids and SimPlot analysis provided evidence that RNA recombination events located in the 1250 to 1350 nucleotide region resulted in new combinations of the N-terminal and C-terminal capsid regions. The high level of capsid sequence diversity observed in the present study has important implications for both the control and diagnosis of ANV infections.


Assuntos
Avastrovirus/genética , Avastrovirus/metabolismo , Proteínas do Capsídeo/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Variação Genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Clonagem Molecular , Dados de Sequência Molecular , Filogenia
19.
Eur Rev Med Pharmacol Sci ; 25(11): 4139-4148, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34156694

RESUMO

OBJECTIVE: The aim of this study is to analyze the disease prevalence of a rural African village and discuss how to maximize the outcomes of health projects. The analysis was based on electronic medical records (EMR) at a clinic in Bududa, Uganda. The installation of EMR in such a low-resource setting enabled efficient statistical analysis. MATERIALS AND METHODS: Medical records from January 2013 to September 2017 were analyzed. During the study period, the top five disease categories diagnosed in Bududa district were diseases of the respiratory system, certain infectious and parasitic diseases, diseases of the digestive system, diseases of the skin and subcutaneous tissue, and others. RESULTS: Infectious and parasitic disease, diseases of digestive system, and diseases of skin and subcutaneous tissue are major diseases. With the exception of the year 2017, extracted data shows that there is a significant increased prevalence of malaria after the rainy season, April and May. CONCLUSIONS: The authors expect an installation of EMR in the developing world in association with epidemiological research will guide different stakeholders including the government and healthcare providers to optimize the use of limited resources for which disease categories at what time. In addition, establishing a map of disease prevalence and incidence will yield more cost-effective strategies for enhancing the quality of life in low-resource settings.


Assuntos
Registros Eletrônicos de Saúde , Países em Desenvolvimento , Acessibilidade aos Serviços de Saúde , Inquéritos Epidemiológicos , Humanos , População Rural , Uganda
20.
Int J Androl ; 33(3): 507-17, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19392831

RESUMO

Evidence from several models of hormone depletion and/or replacement and from knockout animals points to a key role of androgens in the control of spermatogenesis. In testes of mice with a Sertoli cell-selective ablation of the androgen receptor (SCARKO), transcriptional profiling, using microarray technology, revealed that, already on postnatal day 10,692 genes are differentially expressed compared with testes of control mice. Further evaluation of a subset of these genes by quantitative RT-PCR suggested that differences in expression may already be evident on day 8 or earlier. As the androgen receptor in mouse Sertoli cells becomes immunologically detectable around day 5, we tried to identify the earliest responses to androgens by a new transcriptional profiling study on testes from 6-day-old SCARKO and control mice. No obvious and novel early androgen response genes, potentially acting as mediators of subsequent indirect androgen actions, could be identified. However, several genes differentially expressed on day 10 already displayed a response to androgen receptor ablation on day 6. Quantitative RT-PCR studies for 12 of these genes on 10 paired SCARKO and control testes from 4-, 6-, 8-, 10-, 20- and 50-day-old mice revealed significant differences in expression level from day 4 onwards for three genes (Eppin, PCI, Cldn11) and from day 6 onwards for one more gene (Rhox5). For at least two of these genes (Rhox5 and Eppin), there is evidence for direct regulation via the androgen receptor. For three additional genes (Gpd1, Tubb3 and Tpd52l1) significantly lower expression in the SCARKO was noted from day 8 onwards. For all the studied genes, an impressive increase in transcript levels was observed between day 4-50 and differential expression was maintained in adulthood. It is concluded that the SCARKO model indicates incipient androgen action in mouse Sertoli cells from day 4 onwards.


Assuntos
Receptores Androgênicos/genética , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Testículo/metabolismo , Androgênios/genética , Androgênios/metabolismo , Androgênios/farmacologia , Animais , Cruzamentos Genéticos , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores Androgênicos/metabolismo , Receptores Androgênicos/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética , Espermatogênese/fisiologia , Testículo/efeitos dos fármacos
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