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1.
Chem Commun (Camb) ; 56(27): 3891-3894, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32134050

RESUMEN

We utilized electrostatic interaction to induce rapid crystallization of streptavidin. Simply mixing streptavidins possessing either a positively or negatively charged peptide at their C-terminus generated diffraction-quality crystals in a few hours. We modified the streptavidin crystals with fluorescent molecules using biotin, demonstrating the concept of protein crystals as functional biomaterials.


Asunto(s)
Péptidos/química , Estreptavidina/química , Biotina/análogos & derivados , Biotina/química , Biotinilación , Cristalización , ADN/química , Dendrímeros/química , Fluoresceínas/química , Colorantes Fluorescentes/química , Electricidad Estática
2.
Diabetes Metab ; 43(5): 430-437, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28648835

RESUMEN

AIM: This study evaluated the effects of a glucagon-like peptide-1 receptor agonist on gastrointestinal (GI) tract motility and residue rates by examining GI transit time and lumen using capsule endoscopy. MATERIAL AND METHODS: GI motility and lumen were assessed by capsule endoscopy before and after liraglutide administration in 14 patients with type 2 diabetes mellitus (T2DM). RESULTS: Gastric transit time in the group with diabetic neuropathy (DN) was 1:12:36±1:04:30h before liraglutide administration and 0:48:40±0:32:52h after administration (nonsignificant difference, P=0.19). Gastric transit time in the non-DN group was 1:01:30±0:52:59h before administration and 2:33:29±1:37:24h after administration (significant increase, P=0.03). Duodenal and small intestine transit time in the DN group was 4:10:34±0:25:54h before and 6:38:42±3:52:42h after administration (not significant, P=0.09) and, in the non-DN group, 3:51:03±0:53:47h before and 6:45:31±2:41:36h after administration (significant increase, P=0.03). The GI residue rate in the DN group was 32.1±24% before administration and 90.0±9.1% after administration (significant increase, P<0.001), and increased in all patients; in the non-DN group, it was 32.1±35.3% before and 78.3±23.9% after administration (significant increase, P<0.001), and also increased in all patients. CONCLUSION: Liraglutide causes delayed gastric emptying and inhibits duodenal and small intestine motility. However, these GI movement-inhibiting effects may be decreased or absent in patients with DN-associated dysautonomia.


Asunto(s)
Neuropatías Diabéticas/fisiopatología , Motilidad Gastrointestinal/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Liraglutida/farmacología , Anciano , Endoscopía Capsular , Humanos , Masculino , Persona de Mediana Edad , Alcohol Feniletílico/análogos & derivados
3.
Mater Sci Eng C Mater Biol Appl ; 61: 499-505, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26838877

RESUMEN

The rolling rate (r) dependence of textures was investigated in the Ti-26Nb-3Al (mol%) alloy to reveal the conditions required to form the {001}<110> recrystallization texture, which is a desirable orientation for the ß-titanium shape memory alloy. {001}<110> was the dominant cold-rolling texture when r=90% and it was transferred to the recrystallization texture without forming {112}<110>, which is detrimental for the isotropic mechanical properties of the rolled sheet. A further increase in r resulted in the formation of {112}<110> in both rolling and recrystallization textures. Therefore, r should be controlled to form only the {001}<110> rolling texture, because the {112}<110> texture can overwhelm the {001}<110> texture during recrystallization.


Asunto(s)
Aleaciones Dentales/química
4.
Clin Exp Obstet Gynecol ; 43(4): 504-508, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29734536

RESUMEN

PURPOSE: To investigate the efficacy of the combination of ultrasound-guided rectus sheath (RS) and transversus abdominis plane (TAP) blocks compared with TAP or RS block alone in gynecological single-incision laparoscopic surgery (SILS). MATERIALS AND METHODS: Bilateral TAP blocks (Group A, n = 12), TAP and RS blocks (Group B, n = 12), and RS blocks (Group C, n = 12) with 40 ml ropivacaine/patient were performed for ovarian tumor SILS. The analgesic effects were evaluated using a numerical rating scale (NRS) at zero, six, 12, 24, and 48 hours post-surgery. RESULTS: Umbilical pain on completion of general anesthesia was significantly less frequent in Group B (1/12) than Group A (7/12) (p = 0.03). The postoperative NRS scores were significantly lower in Group B than Group A at zero (p = 0.02) and six (p = 0.03) hours and Group C at zero (p = 0.001), six (p = 0.02), and 12 (p = 0.004) hours. CONCLUSION: The combination of RS and TAP blocks reduced early postoperative pain compared with RS or TAP block alone for gynecological SILS.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Laparoscopía/efectos adversos , Bloqueo Nervioso , Neoplasias Ováricas/cirugía , Dolor Postoperatorio/prevención & control , Músculos Abdominales , Pared Abdominal , Adulto , Amidas/uso terapéutico , Anestesia General , Femenino , Humanos , Persona de Mediana Edad , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Estudios Retrospectivos , Ropivacaína , Adulto Joven
5.
Odontol. pediatr. (Lima) ; 14(1): 67-75, ene.-jul.2015. ilus, tab
Artículo en Español | LILACS, LIPECS | ID: lil-790458

RESUMEN

La maloclusión pseudoclase III es caracterizada par un desequilibrio funcional que, por lo general, resulta de contactos oclusales prematuros que causan un desplazamiento funcional anterior de la mandíbula. Estos casos, si no son tratados en una etapa inicial de desarrollo, pueden generar interferencias en el crecimiento normal de las bases óseas y resultar en una deformidad facial. Este papel conlleva a la selecci6n de un aparato apropiado, tomando cuenta opciones actuales, para una intervenci6n temprana en el desarrollo de maloclusiones de clase III. El uso del aparato progenico en este tipo de maloclusión, permite la correcci6n dental en pocos meses y una estabilidad terapéutica de la mandíbula mesio-posicionada fomentando un crecimiento esquelético favorable en una niña de 5,6 años de edad que acude a la clínica de postgrado del Instituto Latino Americano de Investigaci6n y Enseñanza Odontológica (ILAPEO) en Curitiba, Brasil...


Pseudo Class III malocclusion is a functional imbalance that generally results from premature occlusal contacts that causes a functional anterior displacement of the mandible. These cases, if not treated at an early stage of development, may interfere in normal growth of bone bases, resulting in facial deformity. This paper suggests the selection of an adequate appliance considering the available possibilities for early intervention of Class III malocclusion. The use of the progenic appliance in such dental malocclusion allows correction in a few months and therapeutic stability mesio-positioned mandible encouraging favorable skeletal growth in a child of 5.6 years of age who came to the Postgraduate Clinic of the Latin American Institute of Dental Research and Education (ILAPEO) in Curitiba, Brazil...


Asunto(s)
Humanos , Femenino , Preescolar , Maloclusión de Angle Clase III , Ortodoncia Correctiva , Brasil
6.
Analyst ; 139(8): 1953-9, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24579089

RESUMEN

Two analytical methods for the evaluation of photocatalytic oxidation and reduction abilities were developed using a photocatalytic microreactor; one is product analysis and the other is reaction rate analysis. Two simple organic conversion reactions were selected for the oxidation and reduction. Since the reactions were one-to-one conversions from the reactant species to the product species, the product analysis was simply performed using gas chromatography, and the reactions were monitored in situ in the photocatalytic microreactor using the UV absorption spectra. The partial oxidation and reduction abilities for each functional group can be judged from the yield and selectivity, and the corresponding reaction rate, while the total oxidation ability can be judged from the conversion. We demonstrated the application of these methods for several kinds of visible light photocatalysts.

7.
J Clin Pharm Ther ; 38(1): 74-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22971159

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Both itraconazole (ITCZ) and voriconazole (VCZ) are potent inhibitors of cytochrome P450 (CYP) 3A, and their effects have been reported to be equal. However, ITCZ is metabolized by CYP3A, whereas VCZ is mainly metabolized by CYP2C9 and CYP2C19 and only partially by CYP3A. We experienced the case of a patient who showed a 5-fold increase in trough levels of tacrolimus (FK) level after switching from ITCZ to VCZ. Our objective is to discuss the mechanism of the increase drug-drug interaction in terms of serum concentration of the azole drugs and patient pharmacogenomics. CASE SUMMARY: A 53-year-old woman was treated with FK (1 mg/day) for lupus nephritis. Because fungal infection was suspected, she received ITCZ (100 mg/day). When ITCZ was replaced with VCZ (400 mg/day), the blood concentration of FK increased markedly from 6·1 to 34·2 ng/mL. During coadministration with FK, the levels of ITCZ and VCZ were 135·5 ng/mL and 5·5 µg/mL, respectively, with the VCZ level around 3-fold higher than the previously reported level (1·4-1·8 µg/mL). Her CYP genotypes were CYP2C19*1/*2, CYP3A4*1/*1 and CYP3A5*3/*3. WHAT IS NEW AND CONCLUSION: The patient was a CYP2C19 intermediate metabolizer (IM) and deficient in CYP3A5. The increase in plasma VCZ level appears to have been at least in part, associated with the CYP2C19 IM phenotype. One possible explanation for the marked increase in blood FK concentration was increased inhibition of CYP3A because of the impaired metabolism and subsequent increased plasma concentration of VCZ. This case shows that the severity of drug interactions may be influenced by metabolic gene polymorphism.


Asunto(s)
Antifúngicos/farmacocinética , Inmunosupresores/farmacocinética , Nefritis Lúpica/tratamiento farmacológico , Tacrolimus/farmacocinética , Antifúngicos/farmacología , Hidrocarburo de Aril Hidroxilasas/genética , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP3A/genética , Interacciones Farmacológicas , Femenino , Genotipo , Humanos , Inmunosupresores/uso terapéutico , Itraconazol/farmacocinética , Itraconazol/farmacología , Persona de Mediana Edad , Farmacogenética , Polimorfismo Genético , Pirimidinas/farmacocinética , Pirimidinas/farmacología , Tacrolimus/uso terapéutico , Triazoles/farmacocinética , Triazoles/farmacología , Voriconazol
8.
Anal Biochem ; 421(2): 351-61, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22037290

RESUMEN

Quantitation of individual monoclonal antibodies (mAbs) within a combined antibody drug product is required for preclinical and clinical drug development, including pharmacokinetic (PK), toxicology, stability, and biochemical characterization studies of such drugs. We have developed an antitoxin, XOMA 3AB, consisting of three recombinant mAbs that potently neutralize the known subtypes of type A botulinum neurotoxin (BoNT/A). The three mAbs bind nonoverlapping BoNT/A epitopes with high affinity. XOMA 3AB is being developed as a treatment for botulism resulting from BoNT/A. To develop antibody-specific assays, we cloned, expressed, and purified BoNT/A domains from Escherichia coli. Each mAb bound only to its specific domain with affinity comparable to the binding to holotoxin. mAb-specific domains were used to develop an enzyme-linked immunosorbent assay (ELISA) for characterization of the integrity and binding activity of the three mAbs in the drug product. An electrochemiluminescence bridging assay that is robust to interference from components in serum was also developed, and we demonstrate that it can be used for PK assays. This type of antigen engineering to generate mAb-specific domains is a general method allowing quantitation and characterization of individual mAbs in a mAb cocktail that binds the same protein and is superior to anti-idiotype approaches.


Asunto(s)
Anticuerpos Monoclonales/análisis , Toxinas Botulínicas Tipo A/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/análisis , Anticuerpos Neutralizantes/inmunología , Toxinas Botulínicas Tipo A/química , Toxinas Botulínicas Tipo A/genética , Toxinas Botulínicas Tipo A/aislamiento & purificación , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Conformación Proteica
9.
Kyobu Geka ; 64(5): 406-9, 2011 May.
Artículo en Japonés | MEDLINE | ID: mdl-21591444

RESUMEN

A 52-year-old woman who presented with acute onset of chest pain was diagnosed with Stanford type A acute aortic dissection by computed tomography at another hospital. She was referred to our department for emergency surgery. The left pericardium visualized via a median sternotomy was clearly defective, and the left phrenic nerve was located ventral to the defect. The ascending aorta and total arch were replaced with an aortic valve and a prosthetic graft, respectively. Postoperative chest radiography excluded left phrenic nerve palsy. The postoperative course was uneventful and the patient was discharged on postoperative day 17.


Asunto(s)
Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Pericardio/anomalías , Enfermedad Aguda , Femenino , Humanos , Persona de Mediana Edad
10.
Leukemia ; 24(10): 1760-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20686505

RESUMEN

Anti-CD20 antibody rituximab is now essential for the treatment of CD20-positive B-cell lymphomas. Decreased expression of CD20 is one of the major mechanisms underlying both innate and acquired resistance to rituximab. In this study, we show that histone deacetylase (HDAC) inhibitors augment the cytotoxic activity of rituximab by enhancing the surface expression of CD20 antigen on lymphoma cells. HDAC inhibitors, valproic acid (VPA) and romidepsin, increased CD20 expression at protein and mRNA levels in B-cell lymphoma cell lines with relatively low CD20 expression levels. The VPA-mediated increase in CD20 expression occurred at 1 m, which is clinically achievable and safe, but insufficient for inducing cell death. Chromatin immunoprecipitation assays revealed that HDAC inhibitors transactivated the CD20 gene through promoter hyperacetylation and Sp1 recruitment. HDAC inhibitors potentiated the activity of rituximab in complement-dependent cytotoxic assays. In mouse lymphoma models, HDAC inhibitors enhanced CD20 expression along with histone hyperacetylation in transplanted cells, and acted synergistically with rituximab to retard their growth. The combination with HDAC inhibitors may serve as an effective strategy to overcome rituximab resistance in B-cell lymphomas.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígenos CD20/metabolismo , Depsipéptidos/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/metabolismo , Ácido Valproico/farmacología , Acetilación , Animales , Antibióticos Antineoplásicos/farmacología , Anticuerpos Monoclonales de Origen Murino , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular/efectos de los fármacos , Inmunoprecipitación de Cromatina , Sinergismo Farmacológico , Citometría de Flujo , Humanos , Linfoma de Células B/patología , Ratones , Ratones SCID , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rituximab
12.
Oncogene ; 28(2): 231-42, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18850009

RESUMEN

Multiple myeloma (MM) is incurable, mainly because of cell adhesion-mediated drug resistance (CAM-DR). In this study, we performed functional screening using short hairpin RNA (shRNA) to define the molecule(s) responsible for CAM-DR of MM. Using four bona fide myeloma cell lines (KHM-1B, KMS12-BM, RPMI8226 and U266) and primary myeloma cells, we identified CD29 (beta1-integrin), CD44, CD49d (alpha4-integrin, a subunit of VLA-4), CD54 (intercellular adhesion molecule-1 (ICAM-1)), CD138 (syndecan-1) and CD184 (CXC chemokine receptor-4 (CXCR4)) as major adhesion molecules expressed on MM. shRNA-mediated knockdown of CD49d but not CD44, CD54, CD138 and CD184 significantly reversed CAM-DR of myeloma cells to bortezomib, vincristine, doxorubicin and dexamethasone. Experiments using blocking antibodies yielded almost identical results. Bortezomib was relatively resistant to CAM-DR because of its ability to specifically downregulate CD49d expression. This property was unique to bortezomib and was not observed in other anti-myeloma drugs. Pretreatment with bortezomib was able to ameliorate CAM-DR of myeloma cells to vincristine and dexamethasone. These results suggest that VLA-4 plays a critical role in CAM-DR of MM cells. The combination of bortezomib with conventional anti-myeloma drugs may be effective in overcoming CAM-DR of MM.


Asunto(s)
Ácidos Borónicos/farmacología , Adhesión Celular/fisiología , Resistencia a Antineoplásicos/efectos de los fármacos , Cadenas alfa de Integrinas/fisiología , Integrina alfa4/fisiología , Integrina alfa4beta1/fisiología , Mieloma Múltiple/metabolismo , Proteínas de Neoplasias/fisiología , Pirazinas/farmacología , Anticuerpos/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Bortezomib , Moléculas de Adhesión Celular/fisiología , Línea Celular Tumoral/metabolismo , Dexametasona/farmacología , Regulación hacia Abajo , Doxorrubicina/farmacología , Resistencia a Antineoplásicos/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Cadenas alfa de Integrinas/biosíntesis , Cadenas alfa de Integrinas/genética , Integrina alfa4/biosíntesis , Integrina alfa4/genética , Mieloma Múltiple/tratamiento farmacológico , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Vincristina/farmacología
13.
Reprod Domest Anim ; 43(2): 157-61, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18325005

RESUMEN

This study was conducted to examine the effects of the reproductive cycle of donor cat on the quality of oocytes at recovery and developmental competence of oocytes after in vitro fertilization (IVF) and somatic cell nuclear transfer (NT). Based on the presence or absence of follicles and corpora lutea, the ovarian pairs collected were classified into inactive, follicular or luteal stages. After collection of oocytes, the oocytes were classified into four grades according to the morphological condition of oocyte cytoplasm and cumulus cells. A total of 16 558 oocytes were obtained from 198 ovarian pairs. The total mean numbers of oocytes and the mean numbers of oocytes with high quality (grade I) were significantly higher in ovarian pairs at the inactive stage (111.1 and 19.0 oocytes, respectively) than in ovarian pairs at the follicular stage (67.1 and 11.4 oocytes, respectively). A significant difference in the proportions of oocytes with grade I out of the total examined oocytes was observed between the follicular and luteal stages of ovaries (14.9% vs 20.2%, p < 0.05). The proportions of IVF embryos cleaved and developed to blastocysts significantly decreased with decreased quality of oocytes at recovery, irrespective of the reproductive status of ovaries. Moreover, there were no significant differences in the proportions of cleavage and development to the blastocyst stage of IVF and NT embryos among three oestrous stages of ovaries. These results indicate that the reproductive cycle stage of donor cat ovaries has no apparent effects on the in vitro development of oocytes after IVF and NT, but the quality of oocytes at recovery influences the development of IVF embryos.


Asunto(s)
Fertilización In Vitro/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Oocitos/fisiología , Animales , Blastocisto/fisiología , Gatos , Técnicas de Cultivo , Femenino , Masculino , Folículo Ovárico/citología
14.
Oncogene ; 27(22): 3102-10, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18071308

RESUMEN

PKC412 is a staurosporine derivative that inhibits several protein kinases including FLT3, and is highly anticipated as a novel therapeutic agent for acute myeloblastic leukemia (AML) carrying FLT3 mutations. In this study, we show that PKC412 exerts differential cell cycle effects on AML cells depending on the presence of FLT3 mutations. PKC412 elicits massive apoptosis without markedly affecting cell cycle patterns in AML cell lines with FLT3 mutations (MV4-11 and MOLM13), whereas it induces G2 arrest but not apoptosis in AML cell lines without FLT3 mutations (THP-1 and U937). In MV4-11 and MOLM13 cells, PKC412 inactivates Myt-1 and activates CDC25c, leading to the activation of CDC2. Activated CDC2 phosphorylates Bad at serine-128 and facilitates its translocation to the mitochondria, where Bad triggers apoptosis. In contrast, PKC412 inactivates CDC2 by inducing serine-216 phosphorylation and subsequent cytoplasmic sequestration of CDC25c in THP-1 and U937 cells. As a result, cells are arrested in the G2 phase of the cell cycle, but do not undergo apoptosis because Bad is not activated. The FLT3 mutation-dependent differential cell cycle effect of PKC412 is considered an important factor when PKC412 is combined with cell cycle-specific anticancer drugs in the treatment of cancer and leukemia.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Leucemia Mieloide Aguda/genética , Mutación , Estaurosporina/análogos & derivados , Tirosina Quinasa 3 Similar a fms/genética , Apoptosis/efectos de los fármacos , Apoptosis/genética , Proteína Quinasa CDC2 , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclina B/metabolismo , Quinasas Ciclina-Dependientes , Humanos , Leucemia Mieloide Aguda/patología , Fosforilación , Serina/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Estaurosporina/farmacología , Células U937 , Proteína Letal Asociada a bcl/metabolismo , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/metabolismo
15.
Anim Reprod Sci ; 99(3-4): 389-94, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16989965

RESUMEN

The objectives of the present study were to investigate the effects of the stage of the estrous cycle at the start of an estradiol benzoate (EB) and progesterone (P) based treatment protocol on new follicular wave emergence, subsequent estrus and ovulation. The experiment was conducted using a crossover design with each cow (five cross-bred cows) being assigned to one of three groups at 3-month intervals within a 1-year period. Estrous cycle stage in individual cows was initially synchronized with prostaglandin F(2)alpha. After detection of estrus, each cow was injected intramuscularly (i.m.) with 2 mg EB and 200 mg P (EB/P) on day 5, 12 or 17 of the estrous cycle (estrus=day 0), followed by 1 mg EB i.m. 12 days after the EB/P treatment. Ovarian ultrasonographic examinations showed that the emergence of a new follicular wave occurred after EB/P treatment in all groups and the mean interval from EB/P treatment to wave emergence did not differ among the groups (3.2-3.8 days). All cows in each group exhibited behavioral estrus and ovulated the newly formed dominant follicle. However, cows in the day-17 group exhibited estrus 1-3 days before the second EB injection. The concentrations of progesterone showed faster reduction, during the treatment period, in the day-12 and -17 groups compared to the day-5 group. These results indicate that the EB/P treatment induces an emergence of a new follicular wave, irrespective of the estrous cycle stage at the start of treatment, but the effect of EB/P protocol on estrous/ovulation synchronization is influenced by the stage of the estrous cycle.


Asunto(s)
Bovinos/fisiología , Cuerpo Lúteo/efectos de los fármacos , Estro/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Ovulación/efectos de los fármacos , Progesterona/sangre , Animales , Estudios Cruzados , Estradiol/análogos & derivados , Estradiol/farmacología , Ciclo Estral/efectos de los fármacos , Sincronización del Estro/efectos de los fármacos , Femenino , Fármacos para la Fertilidad Femenina/farmacología , Progesterona/farmacología
16.
Reprod Domest Anim ; 41(1): 17-21, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16420322

RESUMEN

The present study was conducted to examine the meiotic competence of canine oocytes embedded in collagen gel, and to investigate the effects of timed exposure of the oocytes embedded in collagen gel to gonadotrophins during maturation culture, on their nuclear maturation. Cumulus-oocyte complexes (COCs) were collected from bitches at the anoestrous and dioestrous stages of the reproductive cycle. In the first experiment, half of the COCs were embedded in collagen gels. The COCs with or without collagen-gel embedding were cultured in a TCM-199 medium supplemented with 0.1 IU/ml human menopausal gonadotropin (hMG) and 10 IU/ml human chorionic gonadotropin (hCG) for 72 h. In the second experiment, the COCs embedded in collagen gels were cultured in TCM-199 medium with gonadotrophins (hMG and hCG) for various periods (0, 24, 48 and 72 h) and then cultured in the medium without gonadotrophins until reaching total culture period (72 h). The percentage of the oocytes reaching metaphase I and metaphase II (MI/MII) was significantly higher (p < 0.05) in COCs with collagen-gel embedding than in COCs without collagen-gel embedding. The percentage of oocytes that were arrested at the germinal vesicle stage was significantly lower (p < 0.05) in oocytes cultured with gonadotrophins than in oocytes cultured without gonadotrophins. However, there were no significant differences in the percentages of oocytes that reached each stage of meiosis among the groups, irrespective of the duration of exposure to gonadotrophins. These observations indicate that embedding of COCs by collagen gel enhances the meiotic competence of canine oocytes, but removal of hormone supplement from maturation medium does not improve the ability of the oocytes to reach MII stage.


Asunto(s)
Perros/fisiología , Gonadotropinas/farmacología , Meiosis/efectos de los fármacos , Meiosis/fisiología , Oocitos/fisiología , Anestro/fisiología , Animales , Técnicas de Cultivo de Célula/veterinaria , Colágeno , Diestro/fisiología , Femenino
17.
Phys Rev Lett ; 92(24): 246103, 2004 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-15245108

RESUMEN

By using multiwalled carbon nanotubes as an element of a nanobiprism, we evaluated quantitatively the coherence of electrons emitted from tungsten tips at room temperature and 78 K, and found an enhancement of coherence at 78 K. The increase of the transverse coherence length of the electron beam agreed well with that of the inelastic mean free path of electrons in solids, demonstrating the direct relationship between the coherences of the electron beam and the original electronic states. On the basis of this experimental fact, we comment on the interpretation of recent Hanbury Brown-Twiss type experiments for electrons reported by Kiesel et al. [Nature (London) 418, 392 (2002)]].

19.
Mol Genet Genomics ; 269(1): 21-30, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12715150

RESUMEN

To investigate the role of flagella and monomer flagellin in the interaction between Pseudomonas syringae pv. tabaci and plants, non-polar fliC and fliD mutants were produced. The ORFs for fliC and fliD are deleted in the DeltafliC and DeltafliD mutants, respectively. Both mutants lost all flagella and were non-motile. The DeltafliC mutant did not produce flagellin, whereas the DeltafliD mutant, which lacks the HAP2 protein, secreted large amounts of monomer flagellin into the culture medium. Inoculation of non-host tomato leaves with wild-type P. syringae pv. tabaci or the DeltafliD mutant induced a hypersensitive reaction (HR), whereas the DeltafliC mutant propagated and caused characteristic symptom-like changes. In tomato cells in suspension culture, wild-type P. syringae pv. tabaci induced slight, visible HR-like changes. The DeltafliC mutant did not induce HR, but the DeltafliD mutant induced a remarkably strong HR. Expression of the hsr203J gene was rapidly and strongly induced by inoculation with the DeltafliD mutant, compared to inoculation with wild-type P. syringae pv. tabaci. Furthermore, introduction of the fliC gene into the DeltafliC mutant restored motility and HR-inducing ability in tomato. These results, together with our previous study, suggest that the flagellin monomer of pv. tabaci acts as a strong elicitor to induce HR-associated cell death in non-host tomato cells.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Bacterianas/metabolismo , Flagelina/metabolismo , Pseudomonas/metabolismo , Solanum lycopersicum/microbiología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Secuencia de Bases , Células Cultivadas , Medios de Cultivo/análisis , Flagelos/metabolismo , Flagelina/química , Flagelina/inmunología , Eliminación de Gen , Expresión Génica , Genes Bacterianos , Solanum lycopersicum/citología , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Enfermedades de las Plantas/microbiología , Pseudomonas/genética , Proteínas Recombinantes/metabolismo
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