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1.
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
2.
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.

3.
Vet J ; 307: 106203, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39069166

RESUMEN

Virtual reality (VR)-based training has shown some benefits in medical education, supporting skill acquisition, and helping reduce anxiety in real-world settings. However, the use of VR simulators in veterinary education remains limited. This study aimed to introduce a VR simulator to support veterinarian training in canine anaesthesia induction and endotracheal intubation. This study involved a group that learned solely with instructional videos (video group), and one that learned concurrently with the video and VR simulator (VR group). Third- and fourth-year veterinary students were included and underwent a descriptive test on canine endotracheal intubation. Canine endotracheal intubation success rates were compared between the video (n = 364) and VR (n = 60) groups of fifth-year students. A survey on the VR usability was conducted (n=91). The median descriptive test scores improved in the VR (63.3/100) vs the video group (51.5/100). The canine intubation success rates were comparable in the VR and video groups at 84.3 % and 77.4 %, respectively. A total of 90.1 % of the surveyed students rated the ease of use of the simulator highly. Overall, VR simulators were well-received, suggesting benefits in new skill retention. Further studies are required to evaluate the extent of skill improvement through VR-based training, compared to conventional methods, and to assess its impact on student motivation. Evaluating the long-term effects of VR-based training on skill development and retention will also provide a deeper understanding of its educational benefits.

4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
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
12.
Oncogene ; 13(4): 813-22, 1996 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8761303

RESUMEN

HTK is a receptor tyrosine kinase that belongs to the Eph subfamily. An extensive screening using BIAcore system revealed that a colon cancer cell line, C-1, expressed the ligand for HTK. From the conditioned medium of C-1 cells, a soluble form of ligand was purified by receptor affinity chromatography, and the isolation of full-length cDNA revealed that this ligand is identical to the human HTK ligand (HTKL) previously reported. HTK receptor tyrosine phosphorylation was induced by membrane-bound or clustered soluble HTKL but not by unclustered soluble HTKL, indicating that HTKL requires cell-to-cell interaction for receptor activation. Binding analysis demonstrated that HTKL binds to HTK with a much higher affinity (Kd: 1.23 nM) than the other transmembrane-type ligand for Eph family, LERK-2/ELKL (Kd: 135 nM). The expression of HTK in cord blood cells was upregulated after the culture in the presence of stem cell factor. Clustered soluble HTKL stimulated the proliferation of sorted HTK+ cord blood cells and a hematopoietic cell line, UT-7/EPO from which HTK was isolated. These findings suggest the involvement of HTK-HTKL system in the proliferation of HTK+ hematopoietic progenitor cells in the hematopoietic environment.


Asunto(s)
Sangre Fetal/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular , Clonación Molecular , Cartilla de ADN , ADN Complementario , Efrina-B2 , Sangre Fetal/citología , Humanos , Ligandos , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Receptor EphB4 , Proteínas Recombinantes/metabolismo
13.
J Clin Oncol ; 19(18 Suppl): 69S-73S, 2001 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-11560977

RESUMEN

One of every three persons who starts smoking falls ill and dies prematurely because he or she smoked. Smoking has been causally linked to heart disease, cancer, and respiratory diseases and continues to be the number one preventable cause of death in this country. To prevent these deaths and the incidence of these diseases, California's Tobacco Control Program was established in 1989 specifically to reduce tobacco use in the state. The strategy of the program is to "denormalize" tobacco. This strategy emphasizes three areas of programmatic activity: to counter pro-tobacco influences, to reduce exposure to environmental tobacco smoke, and to reduce access to tobacco products, with a focus on both social and commercial sources. A fourth priority area, cessation, is considered more of an outcome. California's Tobacco Control Program has touched the life of every Californian. Adult smoking prevalence in the state has gone from approximately 11% lower than the rest of the nation in 1988 to 20% lower in 1996. There are now approximately one million fewer smokers in California than would have been expected. Overall, per capita cigarette consumption has fallen by more than 50%. Seventy percent of adult smokers reported that they tried to quit in the last year. Exposure to secondhand smoke has plummeted. California's lung and bronchus cancer incidence is already declining at a significantly higher rate than that seen elsewhere in the nation. Youth smoking rates have also declined significantly. However, contrary to the message of its massive public relations campaign, the tobacco industry has not changed its stripes after the national tobacco settlement. They are still aggressively marketing their products to teenagers, ethnic minority groups, and young adults. They need to be combatted with renewed vigor by a vigilant health community.


Asunto(s)
Política de Salud , Medios de Comunicación de Masas , Salud Pública , Cese del Hábito de Fumar , Fumar/epidemiología , Adolescente , Conducta del Adolescente , Adulto , Anciano , California , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Medicina Preventiva , Evaluación de Programas y Proyectos de Salud , Relaciones Públicas , Industria del Tabaco
14.
Exp Hematol ; 27(2): 229-33, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10029161

RESUMEN

We isolated a human leukemic cell line UT-7/GM from UT-7, which can differentiate into mature erythroid cells with erythropoietin (EPO) treatment. Using this cell line, we examined the effect of a truncated human EPO receptor (EPOR-T) on EPO-induced erythroid differentiation. Transfection studies revealed that UT-7/GM cells expressing exogenous EPOR-T were likely to undergo apoptosis even in the presence of EPO. In addition, EPOR-T-transfected cells could not differentiate into hemoglobin-positive cells after administration of EPO. These results suggest that EPOR-T is a negative regulator of EPO-induced anti-apoptosis and EPO-induced erythroid differentiation. The EPOR-T form was expressed in seven of nine cases of myelodysplastic syndrome but not in normal controls. In patients with myelodysplastic syndrome, dysregulated expression of EPOR-T may cause apoptosis and blockage of erythroid differentiation, resulting in ineffective erythropoiesis.


Asunto(s)
Eritropoyesis/fisiología , Eritropoyetina/farmacología , Síndromes Mielodisplásicos/patología , Receptores de Eritropoyetina/fisiología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Genes Dominantes , Humanos , Síndromes Mielodisplásicos/fisiopatología , Receptores de Eritropoyetina/agonistas , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Transfección , Células Tumorales Cultivadas
15.
Exp Hematol ; 25(3): 211-6, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9091296

RESUMEN

Thrombopoietin (TPO) is the ligand of the proto-oncogene product, c-Mpl, and supports the growth and maturation of megakaryocytic cells. Although much attention has been paid to the in vivo role of the TPO/c-Mpl system in the context of maintenance of circulating platelets, still little is understood about how activation of c-Mpl leads to mitogenesis and differentiation inside cells. Tec protein-tyrosine kinase (PTK) is the prototype of a recently emerging subfamily of nonreceptor type PTKs. Tec has been demonstrated to be activated by a wide range of cytokine stimulations. In this paper we show that TPO stimulation also rapidly enhances tyrosine-phosphorylation and activity of the Tec kinase in a human TPO-dependent cell line. In addition, the Vav protein, a blood cell-specific signaling molecule, is shown to be tyrosine-phosphorylated in response to TPO and to be constitutively associated with the Tec protein. From this evidence, we conclude that Tec is involved in the intracellular signaling system of TPO/c-Mpl.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas de Neoplasias , Proteínas Tirosina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Receptores de Citocinas , Trombopoyetina/fisiología , Activación Enzimática , Humanos , Megacariocitos/patología , Fosfoproteínas/metabolismo , Fosfotirosina/metabolismo , Unión Proteica , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-vav , Receptores de Trombopoyetina , Transducción de Señal
16.
J Med Chem ; 35(11): 2085-94, 1992 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-1597858

RESUMEN

A series of spiro[imidazolidine-4,4'(1'H)-quinazoline]- 2,2'5(3'H)-triones were prepared and tested for aldose reductase inhibitory activity. The 6'-halogenated derivatives were found to be highly potent in vitro inhibitors of male rabbit lens aldose reductase and in vivo inhibitors of polyol accumulation in the sciatic nerves of galactosemic rats. Of these, (4R)-6'-chloro-3'-methylspiro[imidazolidine-4,4'(1'H)-quinazoline] -2,2',5(3'H)-trione (67) showed the most potent in vitro and in vivo activities. An oral dose of 3 g/kg of compound 67 caused neither death nor behavioral abnormality in the preliminary acute toxicity study using mice and rats. Compound 67 was selected as a candidate for further evaluation. The quantitative structure-activity relationships in this series are also discussed.


Asunto(s)
Aldehído Reductasa/antagonistas & inhibidores , Imidazoles/síntesis química , Imidazolidinas , Quinazolinas/síntesis química , Compuestos de Espiro/síntesis química , Animales , Imidazoles/farmacología , Imidazoles/toxicidad , Cristalino/efectos de los fármacos , Cristalino/enzimología , Cristalino/metabolismo , Masculino , Matemática , Ratones , Conformación Molecular , Estructura Molecular , Polímeros/metabolismo , Quinazolinas/farmacología , Quinazolinas/toxicidad , Conejos , Ratas , Ratas Endogámicas , Nervio Ciático/efectos de los fármacos , Nervio Ciático/metabolismo , Compuestos de Espiro/farmacología , Compuestos de Espiro/toxicidad , Relación Estructura-Actividad
17.
Invest Ophthalmol Vis Sci ; 33(12): 3292-301, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1428704

RESUMEN

The effects of recombinant basic fibroblast growth factor (FGF), epidermal growth factor (EGF), and transforming growth factor-beta (TGF-beta) on migration of human and bovine corneal cells were determined using checkerboard analysis in Boyden chambers. EGF, FGF, and TGF-beta each stimulated high levels of chemotactic migration. Each growth factor, however, induced a different dose-response pattern. Migration stimulated by FGF reached a plateau at a concentration between 100 and 200 ng/ml for endothelial, epithelial, and stromal fibroblasts. By contrast, chemotactic responses to EGF peaked between 10 and 50 ng/ml, then decreased at higher concentrations. TGF-beta also stimulated a peak in migration in all three corneal cells, but the peak of migration occurred at an approximately 1000-fold lower concentration (1 pg/ml) than for EGF. Checkerboard analysis demonstrated that FGF and EGF, but not TGF-beta, stimulated chemokinesis of bovine, stromal, and endothelial cells. These results demonstrate that FGF, EGF, and TGF-beta induce migration in pure populations of bovine and human corneal cells and support the concept that these growth factors may play key roles in corneal wound healing by regulating migration of corneal cells.


Asunto(s)
Quimiotaxis/efectos de los fármacos , Córnea/citología , Factor de Crecimiento Epidérmico/farmacología , Factores de Crecimiento de Fibroblastos/farmacología , Factor de Crecimiento Transformador beta/farmacología , Animales , Bovinos , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Córnea/efectos de los fármacos , Sustancia Propia/citología , Sustancia Propia/efectos de los fármacos , Endotelio Corneal/citología , Endotelio Corneal/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Humanos , Cicatrización de Heridas/efectos de los fármacos
18.
Invest Ophthalmol Vis Sci ; 35(1): 143-9, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8300341

RESUMEN

PURPOSE: To determine if a scrape injury to cat corneal endothelial cells increases the level of mitogenic proteins such as transforming growth factor alpha (TGF alpha) in aqueous humor. METHODS: Aqueous humor of cats was collected at 0, 2, 6, and 24 hours after wounding the endothelium by contact with a cannula tip. Aqueous humor samples collected from sham-wounded cats served as controls. Aqueous humor samples were analyzed for levels of protein, for mitogenic activity using incorporation of tritiated thymidine by cultures of bovine corneal endothelial cells, and for immunoreactive TGF alpha protein using a specific radioimmunoassay. RESULTS: The average protein level in aqueous humor obtained before wounding was low (0.5 mg/ml), increased 26-fold at 2 hours after injury (13 mg/ml), then progressively decreased at 6 hours (8 mg/ml) and 24 hours (2 mg/ml). Levels of mitogenic activity of aqueous humor samples collected 2, 6, and 24 hours after wounding were 2-fold, 2.5-fold, and 0.6-fold higher, respectively, compared to the level of mitogenic activity measured in aqueous humor collected before wounding (0 hours) or in aqueous humor collected from sham-wounded eyes. TGF alpha concentration in aqueous humor collected before endothelial wounding was low (6.8 ng/ml), increased 14-fold 2 hours after wounding (97.4 ng/ml), then progressively decreased at 6 hours (63.3 ng/ml) and 24 hours (35.5 ng/ml) after wounding. TGF alpha concentrations in aqueous humor collected from sham-wounded eyes at 2 hours (9.5 ng/ml) and 6 hours (5.3 ng/ml) were not significantly different from prewound levels. Detergent extracts of bovine corneal endothelial cells contained substantial levels of TGF alpha immunoreactive protein (20 ng/mg protein). CONCLUSIONS: Wounding of cat endothelium causes a rapid increase in mitogenic proteins in aqueous humor including TGF alpha, which may act by an autocrine mechanism to stimulate endothelial wound healing.


Asunto(s)
Humor Acuoso/metabolismo , Endotelio Corneal/metabolismo , Lesiones Oculares Penetrantes/metabolismo , Factor de Crecimiento Transformador alfa/metabolismo , Animales , Gatos , Bovinos , Células Cultivadas , ADN/biosíntesis , Replicación del ADN , Modelos Animales de Enfermedad , Endotelio Corneal/lesiones , Proteínas del Ojo/metabolismo , Radioinmunoensayo , Cicatrización de Heridas
19.
Invest Ophthalmol Vis Sci ; 33(12): 3302-6, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1428705

RESUMEN

Human corneal epithelial cells are normally shed from the apical surface and replaced primarily by mitosis of basal cells. Growth factors may regulate this process, but the sources for the growth factors have not been fully established. One potential source for growth factors is tear fluid, and epidermal growth factor (EGF) has been detected in the lacrimal gland and in tears. However, the hydrophilic structure and size of growth factors such as EGF may limit penetration to basal layers of intact epithelium. It is possible that turnover of basal human corneal epithelial cells might be regulated by growth factors acting by an autocrine mechanism. To determine if human corneal epithelial cells synthesize a potential autocrine growth factor, the authors analyzed human corneal epithelial cells for transforming growth factor-alpha (TGF-alpha) messenger RNA and protein, a growth factor that is structurally related to EGF and binds to the EGF receptor. Radioimmunoassay of human corneal epithelial cell cultures detected substantial levels of immunoreactive TGF-alpha (3 ng/10(6) cells). Immunohistochemical staining of human corneas also revealed the presence of immunoreactive TGF-alpha in the corneal epithelium. Northern hybridization with a 32P-labeled complementary DNA probe for TGF-alpha generated a single intense band at 4.4 kilobases, indicating the presence of TGF-alpha messenger RNA in cultured human corneal epithelial cells. These results support the hypothesis that normal turnover of corneal epithelium is controlled by the autocrine production of growth factors, such as TGF-alpha. Growth factors present in tears may function primarily as exocrine factors to stimulate healing of epithelial injuries after the epithelial barrier has been damaged.


Asunto(s)
Córnea/metabolismo , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador alfa/genética , Autorradiografía , Northern Blotting , Córnea/citología , Células Epiteliales , Epitelio/metabolismo , Humanos , Inmunohistoquímica , Radioinmunoensayo , Factor de Crecimiento Transformador alfa/metabolismo
20.
Invest Ophthalmol Vis Sci ; 34(7): 2305-12, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8505212

RESUMEN

PURPOSE: The authors investigated whether healing of cat corneal endothelial wounds could be enhanced in vivo by human epidermal growth factor (EGF). METHODS: EGF was administered in sodium hyaluronate to the anterior chamber of cats after an endothelial touch injury. Control contralateral eyes received sodium hyaluronate alone. At selected times after injury, the corneas were evaluated for thickness, the rate of endothelial wound closure, the endothelial cell density, any variation in cell size, the percentage of hexagonal cells, and endothelial cell mitosis. RESULTS: Two days after injury, endothelial wounds of eyes treated with EGF had healed an average of 65 +/- 4% of the initial 38.5 mm2 wound area; paired control eyes had healed an average of 59 +/- 4% (P < 0.05). Both EGF-treated and control wounds had resurfaced over 90% of the initial wound area on day 4 after injury, and the wounds were completely resurfaced by 7 and 14 days after injury in both treatment groups. On days 4 and 7 after injury, the EGF-treated corneas were 5% and 8% thicker (835 versus 796 microns and 786 versus 728 microns, respectively) than the paired control corneas (P < 0.03). On days 10 and 14 after injury, both EGF-treated and control corneas were 19% and 12% thicker, respectively, than prewound the corneal thickness (621 microns). Seven days after injury, the corneas treated with EGF had an average of 76 +/- 28% more (P < 0.05) endothelial cell nuclei labeled with tritiated thymidine compared with that of the paired control eyes (2472 versus 1543 labeled nuclei). Fourteen days after injury, the central endothelial cell density of EGF-treated corneas was an average of 38 +/- 11% higher than that of the paired control eyes (P < 0.01, 1708 versus 1235 cells/mm2). The percentage of hexagonal cells in the wound area was an average of 14 +/- 4% higher (P < 0.01) than that of the paired control eyes (82% versus 69%), and the coefficient of variation of the cell size for EGF-treated corneas was an average of 31% (P < 0.05) smaller than that of the paired control corneas (0.21 versus 0.29 [standard deviation]/mean cell size). CONCLUSIONS: A single intraocular application of EGF formulated in sodium hyaluronate after an endothelial cell injury significantly enhanced multiple parameters that are closely related to improved endothelial cell regeneration.


Asunto(s)
Endotelio Corneal/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Gatos , Recuento de Células , Córnea/efectos de los fármacos , Córnea/patología , Replicación del ADN , Modelos Animales de Enfermedad , Endotelio Corneal/lesiones , Endotelio Corneal/patología , Femenino , Ácido Hialurónico/administración & dosificación , Masculino , Mitosis/efectos de los fármacos , Distribución Aleatoria , Proteínas Recombinantes/farmacología
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