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1.
J Vasc Surg ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38408686

RESUMO

OBJECTIVE: Globally, there has been a marked increase in aortic aneurysm-related deaths between 1990 and 2019. We sought to understand the underlying etiologies for this mortality trend by examining secular changes in both demographics and the prevalence of risk factors, and how these changes may vary across sociodemographic index (SDI) regions. METHODS: We queried the Global Burden of Disease Study (GBD) for aortic aneurysm deaths from 1990 to 2019 overall and by age group. We identified the percentage of aortic aneurysm deaths attributable to each risk factor identified by GBD modeling (smoking, hypertension, lead exposure, and high sodium diet) and their respective changes over time. We then analyzed aneurysm mortality by SDI region. RESULTS: The number of aortic aneurysm-related deaths have increased from 94,968 in 1990 to 172,427 in 2019, signifying an 81.6% increase, which greatly exceeds the 18.2% increase in all-cause mortality observed over the same time interval. Examination of age-specific mortality demonstrated that the number of aortic aneurysm deaths markedly correlated with advancing age. However, when considering rate of death rather than mortality count, overall age-standardized death rates decreased 18% from 2.72 per 100,000 in 1990 to 2.21 per 100,000 in 2019. Analysis of the specific risk factors associated with aneurysm death revealed that the percentage of deaths attributable to smoking decreased from 45.6% in 1990 to 34.6% in 2019, and deaths attributable to hypertension decreased from 38.7% to 34.7%. Globally, hypertension surpassed smoking as the leading risk factor. The reported rate of death was consistently greater as SDI increased, and this effect was most pronounced among low-middle and middle SDI regions (173.2% and 170.4%, respectively). CONCLUSIONS: Despite an overall increase in the number of aneurysm deaths, there was a decrease in the age-standardized death rate, demonstrating that the observed increased number of aortic aneurysm deaths between 1990 and 2019 was primarily driven by an overall increase in the age of the global population. Fortunately, it appears that the increase in overall aneurysm-related deaths has been modulated by improved risk factor modification, in particular smoking. Given the rise in aneurysm-related deaths, global expansion of vascular specialty capabilities is warranted and will serve to amplify improvements in population-based aneurysm health achieved with risk factor control.

2.
Syst Biol Reprod Med ; 68(4): 286-297, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35394393

RESUMO

It has been hypothesized that circulating concentrations of estradiol during the preovulatory period, can impact subsequent progesterone concentrations. Ovulation was synchronized in nonlactating beef cows (n = 53). Cows that exhibited estrus before gonadotrophin-releasing hormone (GnRH)-induced ovulation (d 0) had greater (p<.01) peak concentrations of estradiol compared with cows that did not express estrus (11.5 ± 0.8 vs. 6.2 ± 0.6 pg/mL), respectively, but there was no difference in ovulatory follicle size (p= .80) or interval from GnRH2 to ovulation (p=.23). Circulating concentrations of progesterone during luteal formation (d 3-7; p=.70 and p=.77) or mid-luteal phase (d 8-14; p=.39 and p=.12) were not affected by elevated periovulatory estradiol or an interaction with day. To investigate the direct influence of estradiol on luteal function, ovulation (d 0) was synchronized in nonlactating beef cows and cows were allocated to three groups (control, n = 5; vehicle injection, n = 4; or an estradiol antagonist (Fulvestrant; ICI 182,780), n = 4. Intrafollicular injection of vehicle (100 µL) or an estradiol antagonist (25 µg Fulvestrant in 100 µL) into the largest follicle occurred on d -2. Concentrations of estradiol increased (p<.0001) from d -2 to 0 but did not differ among groups (p>.50). Furthermore, plasma concentrations of progesterone on d 0 through 20 were not affected by treatment (p=.86). These results indicate that elevated preovulatory estradiol before ovulation was not required to prepare granulosa cells for luteinization or subsequent luteal progesterone secretion but did tend to impact luteal lifespan.


Assuntos
Estradiol , Progesterona , Animais , Bovinos , Corpo Lúteo , Feminino , Fulvestranto , Hormônio Liberador de Gonadotropina , Ovulação
3.
J Anim Sci ; 99(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33503237

RESUMO

Blood sample collection from the caudal vena cava at the site of uterine-ovarian drainage provides a more exact evaluation of the concentration and pattern of secretion of uterine or ovarian secreted products for studies of reproductive processes in cyclic and pregnant cattle compared with samples collected from general circulation. This paper describes a thorough and updated procedure for cannulating the coccygeal vein into the caudal vena cava for the collection of serial blood samples at or near the site of uterine-ovarian drainage. Concentrations of progesterone were quantified in cows of different reproductive tract sizes with an active corpus luteum to assess the distance for proper catheter placement compared with circulating concentrations collected from the jugular vein. This procedure has a low risk for side effects, can be used effectively in pregnant animals with no major consequence to the viability of the pregnancy, and provides means for frequent collections up to 12 d.


Assuntos
Corpo Lúteo , Ovário , Animais , Cateterismo/veterinária , Bovinos , Drenagem/veterinária , Feminino , Gravidez , Progesterona
4.
Biol Reprod ; 102(2): 475-488, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31616930

RESUMO

Pig conceptuses secrete estrogens (E2), interleukin 1 beta 2 (IL1B2), and prostaglandins (PGs) during the period of rapid trophoblast elongation and establishment of pregnancy. Previous studies established that IL1B2 is essential for rapid conceptus elongation, whereas E2 is not essential for conceptus elongation or early maintenance of the corpora lutea. The objective of the present study was to determine if conceptus expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and release of PG are important for early development and establishment of pregnancy. To understand the role of PTGS2 in conceptus elongation and pregnancy establishment, a loss-of-function study was conducted by editing PTGS2 using CRISPR/Cas9 technology. Wild-type (PTGS2+/+) and null (PTGS2-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer. Immunolocalization of PTGS2 and PG production was absent in cultured PTGS2-/- blastocysts on day 7. PTGS2+/+ and PTGS2-/- blastocysts were transferred into surrogate gilts, and the reproductive tracts were collected on either days 14, 17, or 35 of pregnancy. After flushing the uterus on days 14 and 17, filamentous conceptuses were cultured for 3 h to determine PG production. Conceptus release of total PG, prostaglandin F2⍺ (PGF2α), and PGE in culture media was lower with PTGS2-/- conceptuses compared to PTGS2+/+ conceptuses. However, the total PG, PGF2α, and PGE content in the uterine flushings was not different. PTGS2-/- conceptus surrogates allowed to continue pregnancy were maintained beyond 30 days of gestation. These results indicate that pig conceptus PTGS2 is not essential for early development and establishment of pregnancy in the pig.


Assuntos
Blastocisto/metabolismo , Ciclo-Oxigenase 2/metabolismo , Implantação do Embrião/fisiologia , Desenvolvimento Embrionário/fisiologia , Endométrio/metabolismo , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas , Ciclo-Oxigenase 2/genética , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Transferência Nuclear , Gravidez , Suínos
5.
Adv Physiol Educ ; 43(4): 458-466, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31460777

RESUMO

In this teaching laboratory, students design and perform an experiment to determine estrogen's role in imprinting the brain of neonatal rats to express either male or female sexual behavior. A discussion question is provided before the laboratory exercise in which each student is asked to search the literature and provide written answers to questions and to formulate an experiment to test the role of estrogen in imprinting the mating behavior of male and female rats. Students discuss their answers to the questions in laboratory with the instructor and design an experiment to test their hypothesis. In male rats, testosterone is converted by aromatase expressed by neurons in the brain to estrogen. Production of estrogen in the brain of neonatal rats imprints mating behavior in males, where a lack of estrogen action in the brain imprints female sexual behavior. The model involves administering exogenous testosterone to imprint male behavior in female pups or administration of an aromatase inhibitor (letrozole) or an estrogen receptor antagonist (ICI 182,780) to imprint female sexual behavior in male pups. In the model, litters of neonatal pups are treated with either carrier (control), testosterone propionate, aromatase inhibitor (letrozole), or an estrogen receptor antagonist (ICI 182,780) postnatally on days 1 and 3. Alteration of mating behavior is evaluated through the numbers of males and females that breed and establish pregnancy. This is a very simple protocol that provides an excellent experiment for student discussion on the effects of hormone action on imprinting brain sexual behavior.


Assuntos
Encéfalo/fisiologia , Hormônios Esteroides Gonadais/fisiologia , Fisiologia/educação , Comportamento Sexual Animal/fisiologia , Animais , Avaliação Educacional/métodos , Feminino , Humanos , Masculino , Vias Neurais/fisiologia , Ratos , Maturidade Sexual/fisiologia
6.
Biol Reprod ; 101(1): 148-161, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31066888

RESUMO

The proposed signal for maternal recognition of pregnancy in pigs is estrogen (E2), produced by the elongating conceptuses between days 11 to 12 of pregnancy with a more sustained increase during conceptus attachment and placental development on days 15 to 30. To understand the role of E2 in porcine conceptus elongation and pregnancy establishment, a loss-of-function study was conducted by editing aromatase (CYP19A1) using CRISPR/Cas9 technology. Wild-type (CYP19A1+/+) and (CYP19A1-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer, which were transferred into recipient gilts. Elongated and attaching conceptuses were recovered from gilts containing CYP19A1+/+ or CYP19A1-/- embryos on day 14 and 17 of pregnancy. Total E2 in the uterine flushings of gilts with CYP19A1-/- embryos was lower than recipients containing CYP19A1+/+ embryos with no difference in testosterone, PGF2α, or PGE2 on either day 14 or 17. Despite the loss of conceptus E2 production, CYP19A1-/- conceptuses were capable of maintaining the corpora lutea. However, gilts gestating CYP19A1-/- embryos aborted between days 27 and 31 of gestation. Attempts to rescue the pregnancy of CYP19A1-/- gestating gilts with exogenous E2 failed to maintain pregnancy. However, CYP19A1-/- embryos could be rescued when co-transferred with embryos derived by in vitro fertilization. Endometrial transcriptome analysis revealed that ablation of conceptus E2 resulted in disruption of a number biological pathways. Results demonstrate that intrinsic E2 conceptus production is not essential for pre-implantation development, conceptus elongation, and early CL maintenance, but is essential for maintenance of pregnancy beyond 30 days .


Assuntos
Embrião de Mamíferos/metabolismo , Estrogênios/metabolismo , Manutenção da Gravidez/fisiologia , Prenhez , Reconhecimento Psicológico/fisiologia , Suínos , Animais , Animais Geneticamente Modificados , Aromatase/genética , Aromatase/metabolismo , Células Cultivadas , Clonagem de Organismos/veterinária , Técnicas de Cultura Embrionária/veterinária , Transferência Embrionária/veterinária , Embrião de Mamíferos/química , Desenvolvimento Embrionário/efeitos dos fármacos , Estrogênios/farmacologia , Feminino , Fertilização/fisiologia , Troca Materno-Fetal/efeitos dos fármacos , Troca Materno-Fetal/fisiologia , Técnicas de Transferência Nuclear , Gravidez , Manutenção da Gravidez/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos , Suínos/embriologia , Suínos/genética , Suínos/metabolismo
7.
Theriogenology ; 131: 123-132, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30959438

RESUMO

This study was designed to examine changes in target transcript abundance in endometrial explants exposed to pregnancy-associated glycoproteins (PAGs). Endometrial explants from pregnant and non-pregnant heifers collected on day18 (day 0: day of insemination) were incubated in the absence or presence of PAGs (15 µg/ml). The PAGs represented a mixture comprised of approximately equal amounts of bovine PAGs 4, 6, and 9. Samples were harvested for RNA extraction after 24 h or 96 h of incubation. Transcript abundance for target genes related to prostaglandin synthesis (PTGES), a chemokine (CXCL5) and tissue remodeling (EMMPRIN; MMPs 1, 2, 3, 7, 8, and 9; PLAU; SPP1; TIMP1 and TIMP2) were analyzed by quantitative PCR. Changes in relative transcript abundance for MMP1, MMP3, MMP7, PLAU, EMMPRIN and SPP1 were observed after PAG exposure in both non-pregnant and pregnant endometrium (P < 0.05). However, some of the transcripts associated with tissue remodeling were altered only at certain time points (either 24 h or 96 h). The transcript for bovine CXCL5 was increased in non-pregnant endometrium four- and six-fold at 24 h and 96 h of PAG exposure, respectively (P < 0.05); in pregnant endometrium, only the 24 h incubation period exhibited an elevation in CXCL5 (P < 0.05). In non-pregnant endometrium, both PTGES and MMP9 were elevated after exposure to PAGs for 24 h (P < 0.05) but not in the other samples. Some interferon-responsive transcripts (IFI6, ISG15) were found to be more abundant (P < 0.05) in pregnant endometrium after 96 h exposure to PAGs compared to endometrium that had not been exposed to the PAGs. Likewise, ISG15 message was elevated (P = 0.06) in non-pregnant endometrium after 24 h incubation with PAGs. These results indicate that the PAGs used in this experiment were able to induce changes in endometrial transcripts encoding for proteins associated with matrix remodeling as well as chemokine production and prostaglandin release.


Assuntos
Bovinos , Endométrio/metabolismo , Glicoproteínas/farmacologia , Animais , Basigina/genética , Basigina/metabolismo , Feminino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , Gravidez , RNA Mensageiro/metabolismo
8.
Biol Reprod ; 99(6): 1244-1254, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29931362

RESUMO

Establishment of pregnancy in cattle is complex and encompasses ovulation, fertilization, blastocyst formation and growth into an elongated conceptus, pregnancy recognition signaling, and development of the embryo and placenta. The objective here was to investigate sire influences on pregnancy establishment in cattle. First, 10 Holstein bulls were classified as high or low fertility based on their sire conception rate (SCR) value. In a field trial, pregnancy at first timed insemination was not different between high and low SCR bulls. Next, 5 of the 10 sires were phenotyped using in vitro and in vivo embryo production. There was no effect of SCR classification on in vitro embryo cleavage rate, but low SCR sires produced fewer day 8 blastocysts. In superovulated heifers, high SCR bulls produced a lower percentage of unfertilized oocytes and fewer degenerated embryos compared to low SCR bulls. Recipient heifers received three to five in vivo produced embryos from either high or low SCR sires on day 7 postestrus. Day 16 conceptus recovery and length were not different between SCR groups, and the conceptus transcriptome was not appreciably different between high and low SCR sires. The reduced ability of embryos from low SCR bulls to establish pregnancy is multifactorial and encompasses sperm fertilizing ability, preimplantation embryonic development, and development of the embryo and placenta after conceptus elongation and pregnancy recognition. These studies highlight the importance of understanding genetic contributions of the sire to pregnancy establishment that is crucial to increase reproductive efficiency in dairy cattle.


Assuntos
Bovinos/fisiologia , Fertilidade/fisiologia , Fertilização/fisiologia , Animais , Técnicas de Cultura Embrionária , Feminino , Inseminação Artificial/veterinária , Masculino , Gravidez , Progesterona/sangue , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Adv Physiol Educ ; 42(1): 56-63, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29341814

RESUMO

In this teaching laboratory, the students are directed in an exercise that involves designing and performing an experiment to determine estrogen's role in regulating delayed implantation (diapause) in female rats. To encourage active participation by the students, a discussion question is provided before the laboratory exercise in which each student is asked to search the literature and provide written answers to questions and to formulate an experiment to test the role of ovarian estrogen in inducing implantation in female rats. One week before the laboratory exercise, students discuss their answers to the questions with the instructor to develop an experiment to test their hypothesis that estrogen is involved with inducing implantation in the rat. A rat delayed implantation model was established that utilizes an estrogen receptor antagonist (ICI 182,780), which inhibits the action of ovarian estrogens. Groups of mated females are treated with either carrier (control) or ICI 182,780 (ICI) every other day, starting on day 2 postcoitus (pc) until day 8 pc. One-half of the females receiving ICI are injected with estradiol-17ß on day 8 pc to induce implantation 4 days after the controls. If the ICI-treated females are not administered estradiol, embryo implantation occurs spontaneously ~4 days after the last ICI injection on day 8. This is a very simple protocol that is very effective and provides an excellent experiment for student discussion on hormone action and the use of agonists and antagonists.


Assuntos
Biologia/educação , Implantação do Embrião/fisiologia , Endocrinologia/educação , Modelos Animais , Reprodução/fisiologia , Treinamento por Simulação/métodos , Animais , Feminino , Humanos , Ratos , Ratos Sprague-Dawley , Estudantes Pré-Médicos
10.
Mol Reprod Dev ; 84(8): 731-743, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28643872

RESUMO

Blood-borne extracellular vesicles (i.e., exosomes and microvesicles) carrying microRNAs (miRNAs) could make excellent biomarkers of disease and different physiologic states, including pregnancy status. We tested the hypothesis that circulating extracellular vesicle-derived miRNAs might differentiate the pregnancy status of cows that had maintained pregnancy to Day 30 from non-pregnant cows or from those that exhibited embryonic mortality between Days 17 and 30 of gestation. Cows were randomly assigned for artificial insemination with fertile semen (n = 36) or dead semen (n = 8; control group) on Day 0 (day of estrus). Blood was collected from all animals on Day 0 and on Days 17 and 24 after artificial insemination. Cows receiving live sperm were retrospectively classified as pregnant on Day 30 (n = 17) or exhibiting embryonic mortality between Days 17 and 30 (n = 19). Extracellular vesicles from Day 17 and 24 samples were isolated from serum using ultra-centrifugation, and their presence was confirmed by nanoparticle tracking and Western blot analyses (for CD81) prior to RNA extraction. MicroRNA sequencing was performed on pregnant, embryonic-mortality, and control cows (n = 4 per day), for a total of 24 independent reactions. In total, 214 miRNAs were identified in serum, 40 of which were novel. Based on differential abundance parameters, we identified 32 differentially abundant loci, representing 27 differentially abundant mature miRNA. At Days 17 and 24, specific miRNAs (e.g., miR-25, -16b, and -3596) were identified that differentiated the pregnancy status. In summary, we identified several circulating extracellular vesicles derived miRNAs that differ in abundance between embryonic mortality and pregnant cows.


Assuntos
Biomarcadores/sangue , MicroRNA Circulante/sangue , Embrião de Mamíferos/fisiologia , Prenhez/sangue , Animais , Bovinos , Feminino , Inseminação Artificial/veterinária , Interleucinas/sangue , Gravidez , Progesterona/sangue
11.
Oncotarget ; 7(43): 69420-69435, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27494870

RESUMO

Endosialin (Tumor Endothelial Marker-1 (TEM-1), CD248) is primarily expressed on pericytes of tumor-associated microvasculature, tumor-associated stromal cells and directly on tumors of mesenchymal origin, including sarcoma and melanoma. While the function of endosialin/TEM-1 is incompletely understood, studies have suggested a role in supporting tumor growth and invasion thus making it an attractive therapeutic target. In an effort to further understand its role in cancer, we previously developed a humanized anti-endosialin/TEM-1 monoclonal antibody (mAb), called ontuxizumab (MORAb-004) for testing in preclinical and clinical studies. We herein report on the generation of an extensive panel of recombinant endosialin/TEM-1 protein extracellular domain (ECD) fragments and novel mAbs against ECD motifs. The domain-specific epitopes were mapped against ECD sub-domains to identify those that can detect distinct structural motifs and can be potentially formatted as probes suitable for diagnostic and functional studies. A number of mAbS were shown to cross-react with the murine and human protein, potentially allowing their use in human animal models and corresponding clinical trials. In addition, pairing of several mAbs supported their use in immunoassays that can detect soluble endosialin/TEM-1 (sEND) in the serum of healthy subjects and cancer patients.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Antígenos de Neoplasias/imunologia , Epitopos/imunologia , Proteínas Recombinantes/imunologia , Animais , Especificidade de Anticorpos/imunologia , Antígenos CD/sangue , Antígenos CD/genética , Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/genética , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Células CHO , Cricetinae , Cricetulus , Reações Cruzadas/imunologia , Células HEK293 , Humanos , Camundongos , Neoplasias/sangue , Neoplasias/imunologia , Neoplasias/metabolismo , Ratos Endogâmicos Lew
12.
Dev Med Child Neurol ; 50(9): 655-63, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18754914

RESUMO

Preterm birth is associated with an increased risk of developmental difficulties. Magnetic resonance imaging (MRI) is increasingly being used to identify damage to the brain following preterm birth. It is hoped this information will aid prognostication and identify neonates who would benefit from early therapeutic intervention. Cystic periventricular white matter damage has traditionally been associated with abnormal motor developmental and cerebral palsy, but its presence on MRI does not preclude normal cognitive development. This has led to increasing interest in the identification of diffuse periventricular white matter damage with conventional and sophisticated MRI. However, the correlation between these appearances and developmental outcome remains unclear. Measurements of the size, volumes, and growth rates of many regions of the brain, such as the corpus callosum, ventricular system, cortex, deep grey matter, and cerebellum, are all also altered following preterm birth, but there is insufficient evidence to use this data in the clinical setting. This article is a review of the current evidence on MRI and developmental outcome, suggesting possible indications for the use of MRI following preterm birth.


Assuntos
Deficiências do Desenvolvimento/etiologia , Imageamento por Ressonância Magnética , Nascimento Prematuro/patologia , Nascimento Prematuro/fisiopatologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Criança , Extremidades/crescimento & desenvolvimento , Extremidades/patologia , Humanos
13.
J Gastroenterol Hepatol ; 23(7 Pt 2): e67-78, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18702686

RESUMO

BACKGROUND AND AIMS: Helicobacter pylori infection activates mitogen-activated protein kinases (MAPK) and modulates cell proliferation and apoptosis. However, the relationship between H. pylori infection and MAPK signaling in controlling cell proliferation and apoptosis is not clear, nor has the role of MAPK on the gastric epithelial cell cycle and proliferation been established. Therefore, we investigated the effects of H. pylori infection and MAPK inhibition on these processes. METHODS: Gastric epithelial cell lines (AGS and MKN45) were infected with H. pylori and/or treated with MAPK inhibitors. Cell cycle and apoptosis were measured by flow cytometry. Cell cycle proteins and proliferation were monitored by western blot and cell count, respectively. RESULTS: Infection with H. pylori resulted in dose-dependent MAPK activation, cell cycle arrest, reduced proliferation and increased apoptosis. The effect of H. pylori and MAPK at various cell cycle checkpoints was noted: MEK1/2 and p38 inhibition increased H. pylori-induced cell cycle G(1) arrest, while JNK inhibition reduced G(1) arrest. MEK1/2 inhibition increased p21, p27 and cyclin E and JNK inhibition additionally increased cyclin D1 expression. Both inhibitors decreased cell proliferation. All inhibitors enhanced apoptosis after H. pylori infection. We also detected MAPK cross-talk in AGS cells: p38 and JNK inhibitors increased ERK activation. The p38 inhibitor increased JNK and the MEK1/2 inhibitor decreased JNK activation only during H. pylori infection. CONCLUSIONS: These results suggest H. pylori and MAPK differentially regulate the cell cycle, proliferation and apoptosis in gastric epithelial cells. The imbalance between H. pylori infection and MAPK activation likely contributes to the H. pylori-induced pathogenesis.


Assuntos
Apoptose , Ciclo Celular , Proliferação de Células , Células Epiteliais/patologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Células Epiteliais/virologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/enzimologia , Mucosa Gástrica/virologia , Infecções por Helicobacter/enzimologia , Infecções por Helicobacter/virologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
FEMS Immunol Med Microbiol ; 53(3): 385-94, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18625013

RESUMO

Emerging evidence has suggested a critical role for activator protein-1 (AP)-1 in regulating various cellular functions. The goal of this study was to investigate the effects of Helicobacter pylori and mitogen-activated protein kinases (MAPK) on AP-1 subcomponents expression and AP-1 DNA-binding activity in gastric epithelial cells. We found that H. pylori infection resulted in a time- and dose-dependent increase in the expression of the proteins c-Jun, JunB, JunD, Fra-1, and c-Fos, which make up the major AP-1 DNA-binding proteins in AGS and MKN45 cells, while the expression levels of Fra-2 and FosB remained unchanged. Helicobacter pylori infection and MAPK inhibition altered AP-1 subcomponent protein expression and AP-1 DNA-binding activity, but did not change the overall subcomponent composition. Different clinical isolates of H. pylori showed various abilities to induce AP-1 DNA binding. Mutation of cagA, cagPAI, or vacA, and the nonphosphorylateable CagA mutant (cagA(EPISA)) resulted in less H. pylori-induced AP-1 DNA-binding activity, while mutation of the H. pylori flagella had no effect. extracellular signal-related kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) each selectively regulated AP-1 subcomponent expression and DNA-binding activity. These results provide more insight into how H. pylori and MAPK modulate AP-1 subcomponents in gastric epithelial cells to alter the expression of downstream target genes and affect cellular functions.


Assuntos
DNA/metabolismo , Células Epiteliais/microbiologia , Helicobacter pylori/imunologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator de Transcrição AP-1/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Deleção de Genes , Humanos , Ligação Proteica
15.
J Neuroimmunol ; 189(1-2): 75-87, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17698208

RESUMO

Microglia are the macrophage population residing in the parenchyma of the central nervous system (CNS), and are thought to play critical roles in CNS development, homeostasis and defense against pathogens. Microglia are capable of rapidly responding to microbial pathogens through engagement of their Toll-like receptors (TLRs). We first compared the efficiency of these responses in primary microglia acutely isolated from adult and neonatal mice. While the cytokine and chemokine responses of adult microglia were generally higher than those of neonatal cells stimulated ex vivo through TLRs, the nitric oxide response of neonatal microglia was markedly enhanced relative to the adult cells. We then went on to identify culture conditions such as exposure to M-SCF or GM-CSF that markedly enhanced the nitric oxide response of microglia, particularly those from the adult CNS. Finally, we demonstrate that the differential nitric oxide response of neonatal and adult microglia is not only limited to the mouse, but also extends to rat microglia.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Microglia/enzimologia , Óxido Nítrico/metabolismo , Animais , Células Cultivadas , Citocinas/genética , Interações Medicamentosas , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Indutores de Interferon/farmacologia , Interferon gama/farmacologia , Lipopeptídeos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/fisiologia , Óxido Nítrico Sintase Tipo II/metabolismo , Peptídeos/farmacologia , Poli I-C/farmacologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Receptores Toll-Like/antagonistas & inibidores , Receptores Toll-Like/fisiologia
16.
Glycobiology ; 16(3): 221-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16319082

RESUMO

The syndecans are a family of transmembrane heparan sulfate proteoglycans (HSPG) that have been implicated in a wide variety of biological functions including the regulation of growth factor signaling, adhesion, tumorigenesis, and inflammation. In the current studies, we examined the regulation of syndecan-4 gene expression in gastric epithelial cells and macrophages in response to infection with live Helicobacter pylori and purified toll-like receptor (TLR) agonists. H. pylori, PAM3CSK4 (a TLR2 agonist), and Escherichia coli flagellin (a TLR5 agonist) all induced the rapid expression of syndecan-4 mRNA in MKN45 gastric epithelial cells. Similarly, lipopolysaccharide (LPS) (a TLR4 agonist) also induced the expression of syndecan-4 in macrophages. The H. pylori- and TLR-induced increase in syndecan-4 mRNA was blocked by the proteosome inhibitor MG-132 suggesting a role for nuclear factor kappaB (NF-kappaB) in the regulation of syndecan-4 gene expression. An 895-bp fragment of the human syndecan-4 promoter was cloned upstream of the luciferase reporter. When transfected into MKN45 cells, the activity of this promoter was inducible by H. pylori and TLR agonists. Inducible activity of the syndecan-4 promoter was blocked by cotransfection with a dominant negative IkappaBalpha expression plasmid. Electrophoretic mobility shift assays (EMSA) demonstrated the presence of a highly conserved NF-kappaB-binding site. Mutation of this site within the context of the full-length syndecan-4 promoter resulted in a complete loss of responsiveness to H. pylori and TLR agonists. These results thus demonstrate that the response of the syndecan-4 gene to infectious agents, or their products, is a direct result of NF-kappaB binding to the promoter and induction of de novo transcription.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Helicobacter pylori/fisiologia , Glicoproteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Proteoglicanas/metabolismo , Receptores Toll-Like/agonistas , Animais , Sítios de Ligação , Linhagem Celular , Células Epiteliais/metabolismo , Mucosa Gástrica/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Glicoproteínas de Membrana/genética , Camundongos , Mutação/genética , Regiões Promotoras Genéticas/genética , Proteoglicanas/genética , RNA Mensageiro/genética , Sindecana-4 , Receptores Toll-Like/metabolismo
17.
Infect Immun ; 73(11): 7535-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16239556

RESUMO

Bacillus anthracis is a spore-forming, gram-positive organism that is the causative agent of the disease anthrax. Recognition of Bacillus anthracis by the host innate immune system likely plays a key protective role following infection. In the present study, we examined the role of TLR2, TLR4, and MyD88 in the response to B. anthracis. Heat-killed Bacillus anthracis stimulated TLR2, but not TLR4, signaling in HEK293 cells and stimulated tumor necrosis factor alpha (TNF-alpha) production in C3H/HeN, C3H/HeJ, and C57BL/6J bone marrow-derived macrophages. The ability of heat-killed B. anthracis to induce a TNF-alpha response was preserved in TLR2-/- but not in MyD88-/- macrophages. In vivo studies revealed that TLR2-/- mice and TLR4-deficient mice were resistant to challenge with aerosolized Sterne strain spores but MyD88-/- mice were as susceptible as A/J mice. We conclude that, although recognition of B. anthracis occurs via TLR2, additional MyD88-dependent pathways contribute to the host innate immune response to anthrax infection.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antígenos de Diferenciação/metabolismo , Bacillus anthracis/imunologia , Receptores Imunológicos/metabolismo , Transdução de Sinais , Esporos Bacterianos/imunologia , Receptor 2 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Aerossóis , Animais , Linhagem Celular , Humanos , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
18.
Helicobacter ; 10(3): 193-204, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15904477

RESUMO

BACKGROUND: Helicobacter pylori is the major pathogen causing chronic gastritis and peptic ulcer disease and is closely linked to gastric malignancy. We have previously shown that H. pylori-induced NF-(kappa)B activation and interleukin (IL)-8 secretion are mediated by Toll-like receptor (TLR) 2 in epithelial cells. However, the TLR2-mediated global gene expression profile of the epithelial cell during H. pylori infection is still unknown. The goal of this study was to identify TLR2-regulated genes in epithelial cells induced by H. pylori. MATERIALS AND METHODS: The HEK293 and HEK-TLR2 cells were cocultured with H. pylori 26695 for 6 hours. Total RNA was extracted and hybridized to the Affymetrix human U133A microarray chipset, which contains 22,283 total probe sets including 14,285 genes. Data analyses were performed using affymetrix suite 5 software. The expression of selected genes in gastric epithelial cells AGS and MKN45 was monitored by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Forty-six genes, contained in 57 probe sets, were induced > 2-fold and three genes (five probe sets) decreased > 2-fold by H. pylori infection of HEK293 cells. Fifty-four genes, contained in 69 probe sets, were induced > 2-fold, whereas only 1 gene was repressed > 2-fold in H. pylori-infected HEK-TLR2 cells. Comparisons of genes induced in HEK293 or HEK-TLR2 cells identified 28 genes whose expression was dependent on the presence of TLR2. Seventeen genes were selected and their expression was assessed using the quantitative RT-PCR in gastric epithelial cells during H. pylori infection. Eight of the 17 genes showed distinct expression patterns in AGS and MKN45 cells after H. pylori stimulation. CONCLUSIONS: The current study investigated the TLR2-mediated global gene changes after H. pylori stimulation in the epithelial cell system. This approach will be helpful in identifying genes whose expression is mediated by specific TLRs and in determining the cellular responses that are responsible for diverse signal pathways during H. pylori infection.


Assuntos
Células Epiteliais/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Helicobacter pylori/patogenicidade , Glicoproteínas de Membrana/metabolismo , Proteínas/metabolismo , Receptores de Superfície Celular/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Mucosa Gástrica/citologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/microbiologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas/genética , Receptor 2 Toll-Like , Receptores Toll-Like
19.
Theriogenology ; 64(9): 1913-27, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15919108

RESUMO

A series of experiments were carried out to develop a new method to reduce pig polyspermic fertilization and produce more normal embryos, in vitro. Experiment 1 determined the effect of methyl-beta-cyclodextrin (MCD) treatment during cryopreservation on sperm acrosome reaction and sperm fertilization. Compared to the non-MCD-treated control, MCD treatment increased the percentage of acrosome-reacted spermatozoa at thawing and 2h after incubation in fertilization medium (P<0.01). Treatment with MCD also increased (P<0.05) sperm-penetration rate, number of spermatozoa in oocytes, and fertilization efficiency in the caffeine-free fertilization medium. Experiment 2 was designed to examine the effect of withdrawal of caffeine (caffeine-free) from fertilization medium on fertilization parameters and early embryo development. Using MCD-treated spermatozoa, there was no difference in sperm-penetration rate, oocyte cleavage rate, and blastocyst formation rate between the caffeine-free and caffeine-supplemented groups. However, polyspermic fertilization rate was lower, and fertilization efficiency and blastocyst cell number were higher in the caffeine-free group compared to the caffeine-supplemented group (P<0.05). Experiment 3 studied the effect of caffeine and different concentrations of spermatozoa on fertilization parameters. Sperm-penetration rate did not differ between the caffeine-free and the caffeine-supplemented groups at different sperm concentrations. Caffeine and sperm concentration had an effect on the number of spermatozoa in oocytes and on the polyspermic fertilization rate (P<0.002). Caffeine also affected fertilization efficiency (P<0.05). In conclusion, treating spermatozoa with MCD and withdrawing caffeine from fertilization medium may provide a new method to produce a large number of normal embryos, in vitro.


Assuntos
Cafeína/administração & dosagem , Desenvolvimento Embrionário , Fertilização in vitro/veterinária , Espermatozoides/fisiologia , Suínos , beta-Ciclodextrinas/administração & dosagem , Reação Acrossômica/efeitos dos fármacos , Animais , Biomarcadores Tumorais , Blastocisto/fisiologia , Fase de Clivagem do Zigoto/efeitos dos fármacos , Criopreservação/métodos , Criopreservação/veterinária , Fertilização/efeitos dos fármacos , Fertilização in vitro/métodos , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
20.
Proc Natl Acad Sci U S A ; 102(14): 5268-73, 2005 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-15795381

RESUMO

Administration of gonadotropin-releasing hormone (GnRH) induces a surge of luteinizing hormone and ovulation in a variety of species, including human beings. Our objectives were to determine the effect of follicle size at the time of ovulation on corpus luteum function and establishment and maintenance of pregnancy in cows in which ovulation was either spontaneous or induced with GnRH. GnRH-induced ovulation of follicles < or approximately = 11 mm in diameter resulted in decreased pregnancy rates and increased late embryonic mortality. This decrease in fertility was associated with lower circulating concentrations of estradiol on the day of insemination, a decreased rate of increase in progesterone after insemination, and, ultimately, decreased circulating concentrations of progesterone. In contrast, ovulatory follicle size had no apparent effect on fertility when ovulation occurred spontaneously. Follicles undergoing spontaneous ovulation do so at a wide range of sizes when they are physiologically mature. Therefore, administration of GnRH to induce ovulation likely initiates a preovulatory gonadotropin surge before some dominant follicles attain physiological maturity. GnRH-induced ovulation of follicles that are physiologically immature has a negative impact on pregnancy rates and late embryonic/fetal survival. These observations in cattle may have implications for assisted reproductive procedures in human beings.


Assuntos
Folículo Ovariano/anatomia & histologia , Folículo Ovariano/fisiologia , Prenhez/fisiologia , Animais , Bovinos , Estradiol/sangue , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação/veterinária , Gravidez , Resultado da Gravidez/veterinária , Prenhez/sangue , Progesterona/sangue
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