RESUMEN
INTRODUCTION: Gallbladder polyps (GBPs) are gallbladder lesions which can progress to gallbladder malignancy. The incidence has been estimated as high as 12.1% of all cholecystectomy patients. Gallbladder malignancy typically presents late, and therefore carries a poor prognosis. By identifying potential GBPs early, it would be possible to treat polyps before they undergo malignant change. The current gold standard for GBP identification is with histological examination which is performed after cholecystectomy. This study sought to assess whether radiological imaging could reliably identify GBPs and therefore guide management. METHODS: 1000 consecutive patients already undergoing cholecystectomy were sampled from two UK hospitals. Patients who underwent ultrasonography and had histological analysis of their gallbladders were selected. Overall 905 patients were included in the study. RESULTS: There were 12 histologically confirmed GBPs in the cohort (1.33%). US correctly detected 1 GBP, with a sensitivity of 8.3% (95% CI 0.2-38.5%) and specificity of 96.0% (95% CI 94.5-97.2%). The overall accuracy was 94.8 (95% CI 93.2-96.2%). CONCLUSION: These data show that US is an ineffective tool for GBP identification. The lack of prior operator exposure, imprecise nature of US and possible obstruction of images from underlying gallstone disease delivered a high rate of false positives. IMPLICATIONS FOR PRACTICE: Surgical or oncological decisions regarding GBPs should not be based upon US findings alone as this would lead to unnecessary interventions. MRI should be investigated as an alternative imaging modality for GBP identification, as its differentiation of soft tissues could guide surgical management.
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Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Pólipos/diagnóstico por imagen , Lesiones Precancerosas/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Colecistectomía , Diagnóstico Diferencial , Diagnóstico Precoz , Femenino , Enfermedades de la Vesícula Biliar/patología , Enfermedades de la Vesícula Biliar/cirugía , Humanos , Masculino , Persona de Mediana Edad , Pólipos/patología , Pólipos/cirugía , Lesiones Precancerosas/patología , Lesiones Precancerosas/cirugía , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Lagenidium giganteum forma caninum infection causes severe cutaneous and disseminated disease in dogs. Currently, diagnosis requires culture and rRNA gene sequencing. OBJECTIVE: To develop and evaluate an ELISA for quantitation of anti-L. giganteum f. caninum IgG in canine serum. ANIMALS: Sera were evaluated from 22 dogs infected with L. giganteum f. caninum, 12 dogs infected with Paralagenidium karlingii, 18 dogs infected with Pythium insidiosum, 26 dogs with nonoomycotic fungal infections or other cutaneous or systemic diseases, and 10 healthy dogs. METHODS: Antigen was prepared from a soluble mycelial extract of L. giganteum f. caninum. Optimal antigen and antibody concentrations were determined by checkerboard titration. Results were expressed as percent positivity (PP) relative to a strongly positive control serum. RESULTS: Medians and ranges for PP for each group were: L. giganteum f. caninum (73.9%, 27.9-108.9%), P. karlingii (55.0%, 21.0-90.6%), P. insidiosum (31.3%, 15.8-87.5%), nonoomycotic fungal infection or other cutaneous or systemic diseases (19.2%, 3.2-61.0%), and healthy dogs (9.9%, 7.6-24.6%). Using a PP cutoff value of 40%, sensitivity and specificity (with 95% CI) of the ELISA for detecting L. giganteum f. caninum infection in clinically affected dogs were 90.9% (72.2-97.5%) and 73.2% (60.4-83.0%), respectively. Specificity in dogs infected with P. karlingii was 41.7% (19.3-68.1%) and with P. insidiosum was 66.7% (43.8-83.7%). CONCLUSIONS AND CLINICAL IMPORTANCE: Quantitation of anti-L. giganteum f. caninum antibodies for detection of this infection in dogs has moderately high sensitivity but poor specificity, the latter because of substantial cross-reactivity with anti-P. karlingii and anti-P. insidiosum antibodies.
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Anticuerpos/inmunología , Enfermedades de los Perros/diagnóstico , Ensayo de Inmunoadsorción Enzimática/veterinaria , Infecciones/veterinaria , Lagenidium/inmunología , Animales , Enfermedades de los Perros/inmunología , Perros , Ensayo de Inmunoadsorción Enzimática/métodos , Infecciones/diagnóstico , Infecciones/inmunologíaRESUMEN
Three-dimensional (3-D) cell cultures are advantageous for modeling complex cellular behavior. A major issue with 3-D cultures grown in Engelbreth-Holm-Swarm (EHS) extracellular matrix extract, however, is the expense. We describe here a simple method using a rubber gasket laid over a coverslip, which provides sufficient 3-D area filled with a minimal amount of EHS, resulting in cost-effective 3-D cellular cultures that are easy to manipulate.
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Técnicas de Cultivo de Célula/métodos , Animales , Técnicas de Cultivo de Célula/economía , Línea Celular , Análisis Costo-Beneficio , Medios de Cultivo/química , Matriz ExtracelularRESUMEN
Cryopreservation of zygotes and subsequent thaw and transfer is an established ART treatment. We assessed if success rates frozen-thawed (day 2) zygotes are comparable with the outcome in fresh cycles of treatment. We performed a prospective follow-up and analysis of all frozen (FZT) and fresh cycles of treatment during a 12 months period. One hundred and nineteen patients in the frozen-thawed and 652 in the fresh group had a transfer. The overall thaw-survival rate was 71.7%. Clinical pregnancy rates per thaw and transfer were respectively 15.1% and 21% in the frozen and 29.1% (per transfer) in the fresh group. Implantation rates in fresh and frozen cycles were 16% and 12.3% respectively. The pregnancy loss rate was higher in the FZT group (29% vs. 18.3%). Cryopreservation of good quality zygotes, after fresh transfer offers optimal success rates in subsequent frozen treatment. It also encourages consideration of elective single zygote transfers.
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Criopreservación , Implantación del Embrión , Transferencia de Embrión , Fertilización In Vitro , Infertilidad Femenina , Índice de Embarazo/tendencias , Cigoto , Femenino , Humanos , Embarazo , Embarazo Múltiple/estadística & datos numéricos , Técnicas Reproductivas AsistidasRESUMEN
Radiation therapy for the treatment of malignant pleural mesothelioma has historically been limited by its efficacy. However, the increasing incidence of this tumour and the emergence of new technologies present a number of opportunities and challenges for this treatment modality. Radiotherapy is used to palliate mesothelioma patients with chest wall pain. Responses of over 60% have been seen, although the duration of response is often disappointing. The optimum dose has not been shown and many of the previous studies were small retrospective studies. An improved response has been seen in several studies where hyperthermia was added to radiotherapy. However, further investigation of this technique, which is not widely available, is required. There has not been any comparison of radiotherapy with chemotherapy in the palliation of patients with malignant pleural mesothelioma. Prophylactic chest wall radiotherapy to intervention sites successfully reduces the incidence of malignant seeding along the intervention tracts. However, the optimum dose and timing of treatment are not clear. There is no role for radical radiotherapy alone, but the role of radiotherapy as part of multimodality therapy is discussed. There have been studies of intensity-modulated radiotherapy as part of multimodality therapy and this technique needs to be evaluated further.
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Mesotelioma/radioterapia , Neoplasias Pleurales/radioterapia , Terapia Combinada , Relación Dosis-Respuesta en la Radiación , Humanos , Hipertermia Inducida , Mesotelioma/complicaciones , Mesotelioma/tratamiento farmacológico , Dolor/etiología , Dolor/radioterapia , Cuidados Paliativos , Neoplasias Pleurales/complicaciones , Neoplasias Pleurales/tratamiento farmacológicoRESUMEN
This retrospective study examines the attrition that occurs from all eggs inseminated and fertilised through to babies taken home in an IVF fresh/frozen programme undertaken between 2001-4. Poor survival rates are to be found, particularly during the recognised in-vitro developmental stages, Present practice which promotes quantity from the start, increases problem potential, is wasteful and against the concept of one embryo one baby. This suggests the need to develop better criteria for egg selection for insemination thus enabling a rethink to the approach to ovarian stimulation of one of quality rather than quantity.
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Fertilización In Vitro , Resultado del Embarazo , Adulto , Transferencia de Embrión , Femenino , Humanos , Masculino , Embarazo , Estudios RetrospectivosRESUMEN
The primary objective of this research was to determine the effect of supplemental dietary silicon (Si) on plasma and milk Si concentrations of lactating mares and the subsequent effect on plasma Si concentrations in nursing foals. Additionally, the role of Si on altering biochemical markers of bone turnover was investigated, because supplemental Si may be advantageous in enhancing bone health. Twelve Arabian mare/foal units were pair-matched by foaling date and randomly assigned to two groups, Si-supplemented (Supplemented) or control (Control). Blood and milk samples were taken on d 0, 15, 30, and 45, d 0 being the 1st d after parturition. Plasma and milk (or colostrum) Si concentrations were determined and serum was analyzed for osteocalcin, carboxy-terminal pyridinoline cross-linked telopeptide region of type I collagen, and pyridinoline and deoxypyridinoline crosslinks. All Supplemented mares had higher (P < 0.01) plasma Si concentrations than Control by d 30, and Supplemented mares' milk had higher (P < 0.01) Si concentrations on d 45 than Control mares' milk. By d 45, foals of Supplemented mares had higher (P < 0.01) plasma Si concentrations than foals of Control mares. Supplemental Si did not influence (P > 0.36) bone metabolism in foals; however, trends (P < 0.10) for altered bone metabolism were observed in postpartum mares. Results indicate that supplemental Si increases plasma and milk Si concentrations. Further research is required to determine whether Si has a role in altering serum biochemical markers of bone and collagen activity.
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Animales Lactantes/sangre , Huesos/metabolismo , Caballos/fisiología , Leche/química , Silicio/metabolismo , Aminoácidos/sangre , Animales , Animales Lactantes/anatomía & histología , Biomarcadores/análisis , Huesos/efectos de los fármacos , Colágeno/sangre , Colágeno Tipo I , Calostro/química , Femenino , Caballos/metabolismo , Lactancia/fisiología , Osteocalcina/sangre , Péptidos/sangre , Distribución Aleatoria , Silicio/administración & dosificación , Silicio/sangreRESUMEN
The transcription factor Pit-1/GHF-1 plays an important role in regulating the prolactin (Prl) and growth hormone (GH) genes in mammals. In this study, the role that Pit-1 plays in regulating the prolactin and growth hormone genes in avian species was examined by cotransfection assays and immunofluorescence staining of pituitary sections. In cotransfection assays, turkey Pit-1 activated the turkey Prl, turkey GH, and rat Prl promoters 3.8-, 3.7-, and 12.5-fold, respectively. This activation was comparable to rat Pit-1 activation of these same promoters. A point mutation in the turkey Pit-1 cDNA, which changed leu-219 to ser-219, resulted in a 2-, 2-, and 10-fold reduction in the activation of the turkey Prl, turkey GH, and rat Prl promoters, respectively. Unexpectedly, coexpression of tPit-1 (leu-219) and tPit-1(ser-219) activated turkey Prl and rat Prl promoters 9.4- and 35.9-fold, respectively, but had no effect on the turkey GH promoter. Dual-label immunofluorescence analysis of turkey pituitary sections revealed that Pit-1 was not detectable in prolactin-staining cells but was detectable in GH-staining cells. Taken together, these data indicate that in the domestic turkey, Pit-1 can activate the turkey Prl promoter in vitro, but does not appear to play a role in regulating Prl gene expression in vivo. Pit-1, however, still likely plays a role in regulating GH gene expression.
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Proteínas de Unión al ADN/farmacología , Hormona del Crecimiento/genética , Hipófisis/química , Prolactina/genética , Regiones Promotoras Genéticas , Factores de Transcripción/farmacología , Pavos/genética , Región de Flanqueo 5' , Animales , Secuencia de Bases , Línea Celular , Núcleo Celular/química , Clonación Molecular , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/genética , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Vectores Genéticos , Hormona del Crecimiento/análisis , Células HeLa , Humanos , Ratones , Datos de Secuencia Molecular , Hipófisis/metabolismo , Hipófisis/ultraestructura , Prolactina/análisis , Ratas , Factor de Transcripción Pit-1 , Factores de Transcripción/análisis , Factores de Transcripción/genética , TransfecciónRESUMEN
Seventeen Arabian weanlings were used to determine the influence of housing on third metacarpal bone mass. Animals were separated into three treatment groups: Pasture (n = 6), Stall (n = 5), and Partial-Pasture (n = 6). Radiographs of the left third metacarpus were taken every 28 d to determine radiographic bone aluminum equivalence (RBAE). Serum was collected every 14 d and analyzed for osteocalcin, carboxyterminal telopeptide of type I collagen (ICTP), and keratan sulfate. Hip and wither height, BW, and cannon circumference were measured every 28 d. Lateral RBAE in the pastured group increased linearly from d 0 to d 56 (P = 0.001). In the Pasture group, total RBAE increased from d 0 to 56 (P = 0.05) and medial RBAE tended to increase from d 0 to d 28 (P = 0.06). The Partial Pasture group increased from d 0 to 56 in medial (P = 0.02) and tended to increase in total RBAE (P = 0.08). Although the Stall group demonstrated an increase in total RBAE from d 0 to 56 (P = 0.04), the Partial Pasture group tended to have greater total RBAE than the Stall group at d 28 (P = 0.08), and the Pasture group had greater lateral RBAE at d 28 (P = 0.005) and 56 (P = 0.007) than did the Stall group. At d 28, medial RBAE was greater in the Pasture (P = 0.003) and Partial Pasture (P = 0.05) groups than in the Stall group. Pasture and Stall groups tended to decrease in osteocalcin (P = 0.06), whereas Partial Pasture weanlings decreased (P = 0.01) from d 0 to 56. All treatment groups decreased from d 0 to 56 in ICTP (P < 0.01). Pastured weanlings decreased from d 0 to 42 in serum keratin sulfate (P < 0.05), whereas the Stall group decreased from d 0 to 56 (P = 0.05). All treatment groups increased in wither height (P < or = 0.01), hip height (P < or = 0.001), and BW (P < or = 0.01). Both the Pasture and Partial Pasture weanlings demonstrated greater cannon circumference than Stall weanlings on d 28 (P < or = 0.05) and 56 (P < or = 0.005). These data demonstrate that pasture rearing or 12-h daily turnout is beneficial to maintaining and increasing bone mineral content in weanling Arabian horses.
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Densidad Ósea , Caballos/fisiología , Vivienda para Animales , Metacarpo/anatomía & histología , Minerales , Destete , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Femenino , Masculino , Osteocalcina/fisiología , Distribución AleatoriaRESUMEN
In human neutrophils, the activation of phospholipase D and the Tyr phosphorylation of proteins are early signaling events upon cell stimulation. We found that the pretreatment of neutrophils with ethanol (0.8%) or 1-butanol (0.3%), which results in the accumulation of phosphatidylalcohol at the expense of phosphatidic acid (PA), decreased the phorbol myristate acetate-stimulated Tyr phosphorylation of endogenous proteins (42, 115 kDa). When neutrophil cytosol was incubated in the presence or absence of PA, these and other endogenous proteins became Tyr-phosphorylated in a PA-dependent manner. In contrast, phosphatidylalcohols exhibited only 25% (phosphatidylethanol) or 5% (phosphatidylbutanol) of the ability of PA to stimulate Tyr phosphorylation in the cell-free assay. Similarly, other phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, phosphatidylinositol, polyphosphoinositides, and sphingosine 1-phosphate) showed little ability to stimulate Tyr phosphorylation. These data suggest that PA can function as an intracellular regulator of Tyr phosphorylating activity. Gel filtration chromatography of leukocyte cytosol revealed a peak of PA-dependent Tyr phosphorylating activity distinct from a previously described PA-dependent phosphorylating activity (Waite, K. A., Wallin, R., Qualliotine-Mann, D., and McPhail, L. C. (1997) J. Biol. Chem. 272, 15569-15578). Among the protein Tyr kinases expressed in neutrophils, only Fgr eluted exclusively in the peak of PA-dependent Tyr phosphorylating activity. Importantly, Fgr isolated from unstimulated neutrophil lysates showed increased activity in the presence of PA but not phosphatidylbutanol. Moreover, the pretreatment of neutrophils with 1-butanol decreased Fgr activity in cells stimulated with formyl-methionyl-leucyl phenylalanine plus dihydrocytochalasin B. Together, these results suggest a new second messenger role for PA in the regulation of Tyr phosphorylation.
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Neutrófilos/metabolismo , Ácidos Fosfatidicos/fisiología , Proteínas Proto-Oncogénicas/metabolismo , 1-Butanol/farmacología , Células Cultivadas , Etanol/farmacología , Glicerofosfolípidos/farmacología , Humanos , Ácidos Fosfatidicos/farmacología , Fosfolipasa D/metabolismo , Fosforilación/efectos de los fármacos , Fosfotirosina/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Familia-src QuinasasRESUMEN
Interferon-gamma (IFN-gamma) is known primarily for its roles in immunological responses but also has been shown to affect fat metabolism and adipocyte gene expression. To further investigate the effects of IFN-gamma on fat cells, we examined the effects of this cytokine on the expression of adipocyte transcription factors in 3T3-L1 adipocytes. Although IFN-gamma regulated the expression of several adipocyte transcription factors, IFN-gamma treatment resulted in a rapid reduction of both peroxisome proliferator-activated receptor (PPAR) protein and mRNA. A 48-h exposure to IFN-gamma also resulted in a decrease of both CCAAT/enhancer-binding alpha and sterol regulatory element binding protein (SREBP-1) expression. The short half-life of both the PPARgamma mRNA and protein likely contributed to the rapid decline of both cytosolic and nuclear PPARgamma in the presence of IFN-gamma. Our studies clearly demonstrated that the IFN-gamma-induced loss of PPARgamma protein is partially inhibited in the presence of two distinct proteasome inhibitors. Moreover, IFN-gamma also inhibited the transcription of PPARgamma, which was accompanied by a decrease in PPARgamma mRNA accumulation. In addition, exposure to IFN-gamma resulted in a substantial increase in STAT 1 expression and a small increase in STAT 3 expression. IFN-gamma treatment of 3T3-L1 adipocytes (48-96 h) resulted in a substantial inhibition of insulin-sensitive glucose uptake. These data clearly demonstrate that IFN-gamma treatment results in the development of insulin resistance, which is accompanied by the regulation of various adipocyte transcription factors, in particular the synthesis and degradation of PPARgamma.
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Proteínas de Unión al ADN/metabolismo , Interferón gamma/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Adipocitos/metabolismo , Animales , Transporte Biológico , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/biosíntesis , Núcleo Celular/metabolismo , Células Cultivadas , Citosol/metabolismo , Proteínas de Unión al ADN/biosíntesis , Dactinomicina/farmacología , Desoxiglucosa/metabolismo , Relación Dosis-Respuesta a Droga , Electroforesis en Gel de Poliacrilamida , Regulación Enzimológica de la Expresión Génica , Immunoblotting , Insulina/metabolismo , Resistencia a la Insulina , Ligandos , Ratones , Regiones Promotoras Genéticas , ARN Mensajero/metabolismo , Factor de Transcripción STAT1 , Factor de Transcripción STAT3 , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Factores de Tiempo , Transcripción GenéticaRESUMEN
BACKGROUND: The technique aspirating spermatozoa from the testis is a new development in male infertility treatment. It is appropriate for infertile couples where the male has azoospermia but is still producing live motile spermatozoa in the testes. AIM: To describe the initial experiences of a testicular sperm extraction programme (TESE) coupled with intracytoplasmic sperm injection (ICSI) in 18 men during 1998. METHODS: Spermatozoa were obtained by direct aspiration from the testes using a 16 gauge needle with cannula and negative suction under local anaesthetic. All samples obtained were to be cryopreserved for use in a subsequent ICSI cycle. RESULTS: All five men with congenital bilateral absence of the vas deferens to be carriers of cystic fibrosis gene mutations. No gene deletions were found in their wives. No other cyto or molecular genetic abnormalities were otherwise found. Twenty one procedures were carried out. The mean number of aspirations was 1.72. Eleven samples from 10 men had sperm suitable for ICSI post-freeze. Post-procedure pain was the universal side-effect. Eight couples had a single attempt at ICSI, two couples two each. Fertilisation rate was 71.4%. Two pregnancies were achieved. CONCLUSION: TESE may give hope in selected cases of azoospermia of fathering a child without the involvement of a third party.
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Inyecciones de Esperma Intracitoplasmáticas , Recolección de Tejidos y Órganos , Adulto , Criopreservación , Femenino , Humanos , Irlanda , Masculino , Oligospermia , Preservación de Semen , Recolección de Tejidos y Órganos/métodosRESUMEN
BACKGROUND: Chemotherapy, radiotherapy and surgery for cancer all carry risks of sterility. Semen cryopreservation would allow procreational ability to be preserved. METHODS: A human-assisted reproduction unit was set up in the Rotunda Hospital where semen was cryopreserved and stored for use. RESULTS: Semen was frozen for procreational potential during 1998 from 58 males about to have oncology therapy likely to render them sterile. The planning for this service and the modus operandi now in place are described. While cryopreservation was not unsuccessful in any case, substandard samples were obtained from 14 men. Pre-freeze viral tests tested positive for CMV in six patients. One pregnancy is already on-going utilising IVF with thawed semen. One patient's death has been notified and the frozen semen disposed of. CONCLUSION: The service is, at present, outside public purse provision. It is hoped that in the near future this will change, as the deficit between charges and costs cannot be sustained in-house forever.
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Criopreservación , Neoplasias , Preservación de Semen , Criopreservación/métodos , Unidades Hospitalarias/organización & administración , Humanos , Irlanda , Masculino , Preservación de Semen/métodosRESUMEN
The mutant Chinese hamster ovary cell line (CHO), MT58, has a temperature-sensitive mutation in CTP:phosphocholine cytidylyltransferase (CT), preventing phosphatidylcholine (PC) synthesis at 40 degrees C which results in apoptosis. Previous studies (Houweling, M., Cui, Z., and Vance, D. E. (1995) J. Biol. Chem. 270, 16277-16282) showed that expression of wild-type CT-alpha rescued the cells at 40 degrees C, whereas expression of phosphatidylethanolamine N-methyltransferase-2 (PEMT2) did not, even though PC levels appeared to be maintained at wild-type levels after 24 h at the restrictive temperature. We report that the failure of PEMT2 to rescue the MT58 cell line is due to inadequate long term PC synthesis. We found that changing the medium every 24 h rescued the PEMT2-expressing MT58 cells grown at 40 degrees C. This was due to the uptake and utilization of lipids in the serum. At 40 degrees C, PC levels in the wild-type CHO cells and CT-expressing MT58 cells increased over time whereas PC levels did not change in both the MT58 and PEMT2-expressing MT58 cell lines. Further investigation found that both the PEMT2-expressing MT58 and MT58 cell lines accumulated triacylglycerol at 40 degrees C. Pulse-chase experiments indicated that lyso-PC accumulated to a higher degree at 40 degrees C in the PEMT2-expressing MT58 cells compared with CT-expressing MT58 cells. Transfection of the PEMT-expressing MT58 cells with additional PEMT2 cDNA partially rescued the growth of these cells at 40 degrees C. Inhibition of PC degradation, by inhibitors of phospholipases, also stimulated PEMT-expressing MT58 cell growth at 40 degrees C. Best results were observed using a calcium-independent phospholipase A(2) inhibitor, methyl arachidonyl fluorophosphonate. This inhibitor also increased PC mass in the PEMT2-expressing MT58 cells. When the cells are shifted to 40 degrees C, PC degradation by enzymes such as phospholipases is greater than PC synthesis in the mutant PEMT2-expressing MT58 cells. Taken together, these results indicate that PEMT2 expression fails to rescue the mutant cell line at 40 degrees C because it does not maintain PC levels required for cellular replication.
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Citidililtransferasa de Colina-Fosfato/genética , Citidina Difosfato Colina/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Fosfatidilcolinas/biosíntesis , Animales , Células CHO , División Celular/efectos de los fármacos , Citidililtransferasa de Colina-Fosfato/metabolismo , Células Clonales , Cricetinae , Medios de Cultivo , Inhibidores Enzimáticos/farmacología , Regulación Enzimológica de la Expresión Génica , Cinética , Metionina/metabolismo , Fosfatidiletanolamina N-Metiltransferasa , Fosfolipasas/antagonistas & inhibidores , Temperatura , Transfección , Triglicéridos/metabolismoRESUMEN
The transcription factor Sp1 has been implicated in regulation of the expression of the murine CTP:phosphocholine cytidylyltransferase alpha (CTalpha) gene, Ctpct (M. Bakovic, K. Waite, W. Tang, I. Tabas, and D. E. Vance. 1999. Biochim. Biophys. Acta. 1438: 147;-165). We have utilized transient transfections, mutation analysis, electromobility gel-shifts, and immunoblot analysis to test the hypothesis that expression of the CTalpha gene is controlled in part by the binding of three trans-acting nuclear factors, Sp1, Sp2, and Sp3. Sp1 and Sp3 activate CTalpha gene transcription through sequence specific binding within three promoter domains. In Sp1-mediated transcription, Sp3 acts as an activator in a dose-dependent manner and vice versa. Sp2 represses Sp1- and Sp3-driven transcription in Drosophila SL2 cells, but stimulates transcription in C3H10T1/2 mammalian cells. Our results suggest that the predominant action of Sp proteins is a direct function of local organization of three cis-acting elements in the regions A (-31/-9), B (-88/-50), and C (-148/-128). The ability of distal C (-148/-128) and proximal A (-31/-9) regions to activate or repress transcription depends upon the cellular background. The multiple binding elements at position B (-88/-50) confer a positive regulation independent of the cell context. However, the effectiveness of Sp proteins at this site is strongly governed by neighboring sites A and C. The results suggest that the level of expression of the CTalpha gene will depend on the cell type, the availability of Sp proteins, and the structure and organization of three cis-acting elements.
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Citidililtransferasa de Colina-Fosfato/genética , Proteínas de Unión al ADN/metabolismo , Regiones Promotoras Genéticas , Factor de Transcripción Sp1/metabolismo , Factores de Transcripción/metabolismo , Animales , Unión Competitiva , Citidililtransferasa de Colina-Fosfato/biosíntesis , Proteínas de Unión al ADN/genética , Drosophila/citología , Regulación Enzimológica de la Expresión Génica , Genes Reporteros , Ratones , Modelos Genéticos , Familia de Multigenes , Unión Proteica , Proteínas Recombinantes/biosíntesis , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp2 , Factor de Transcripción Sp3 , Factores de Transcripción/genética , Activación TranscripcionalRESUMEN
Using a phosphorylation-dependent cell-free system to study NADPH oxidase activation (McPhail, L. C., Qualliotine-Mann, D., and Waite, K. A. (1995) Proc. Natl. Acad. Sci. U. S. A. 92, 7931-7935), we previously showed that p47(phox), a cytosolic NADPH oxidase component, is phosphorylated. Now, we show that p22(phox), a subunit of the NADPH oxidase component flavocytochrome b(558), also is phosphorylated. Phosphorylation is selectively activated by phosphatidic acid (PA) versus other lipids and occurs on a threonine residue in p22(phox). We identified two protein kinase families capable of phosphorylating p22(phox): 1) a potentially novel, partially purified PA-activated protein kinase(s) known to phosphorylate p47(phox) and postulated to mediate the phosphorylation-dependent activation of NADPH oxidase by PA and 2) conventional, but not novel or atypical, isoforms of protein kinase C (PKC). In contrast, all classes of PKC isoforms could phosphorylate p47(phox). In a gel retardation assay both the phosphatidic acid-dependent kinase and conventional PKC isoforms phosphorylated all molecules of p22(phox). These findings suggest that phosphorylation of p22(phox) by conventional PKC and/or a novel PA-activated protein kinase regulates the activation/assembly of NADPH oxidase.
Asunto(s)
Proteínas de Transporte de Membrana , NADPH Deshidrogenasa/metabolismo , NADPH Oxidasas/metabolismo , Ácidos Fosfatidicos/metabolismo , Fosfoproteínas/metabolismo , Proteína Quinasa C/metabolismo , Sistema Libre de Células , Activación Enzimática , Isoenzimas/química , Isoenzimas/metabolismo , NADPH Deshidrogenasa/química , NADPH Oxidasas/química , Ácidos Fosfatidicos/química , Fosfoproteínas/química , Fosforilación , Proteína Quinasa C/químicaRESUMEN
The Th1/Th2 cytokine balance is important in persistence of infection and liver injury in chronic hepatitis C. The aim of this study was to administer the anti-inflammatory cytokine, recombinant human interleukin-10 (rHuIL-10), for 28 days in patients with chronic hepatitis C and to assess the safety and measure the effect on alanine aminotransferase (ALT, a marker of hepatic inflammation) levels and serum hepatitis C virus (HCV) RNA values. Three treatment-naive and 13 interferon (IFN) nonresponder patients (total 16 patients) with compensated chronic HCV infection were enrolled in this study. Patients were randomized to receive rHuIL-10 at a dose of 4 or 8 microg/kg/day as a single daily subcutaneous injection for 28 days. ALT values and serum HCV RNA were measured at days 0, 1, 3, 8, 15, 22, and 28 during therapy and at follow-up 2 and 4 weeks after cessation of the 4-week treatment period. ALT values normalized in 9 of 16 patients during therapy and remained normal until the end of treatment in 8 patients. The decreases in ALT values occurred in both the 4 microg and 8 microg dosage groups and were seen in both IFN naive and nonresponder patients. Mean ALT values fell significantly during the study period but usually returned to pretreatment levels by the end of the 4-week follow-up period (p < 0.05). HCV RNA concentrations did not vary significantly during or after therapy. (No patient had either an increase or a decrease in HCV RNA levels of > or =1.5 log during the study.) The drug was well tolerated, with no adverse symptoms noted. Platelet counts fell transiently to 73,000 and 63,000 in 2 patients. No other toxicity was observed, and no patients discontinued therapy. In chronic hepatitis C, short-term therapy with IL-10 was well tolerated and caused transient normalization of ALT values in 50% of patients, which returned to pretreatment levels on cessation of treatment. There were no significant changes observed in serum HCV RNA concentrations during the study. These immunomodulatory effects are similar to those observed with ribavirin monotherapy in chronic hepatitis C. Further study of rHuIL-10 alone or in combination with antiviral agents in chronic hepatitis C is warranted.
Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Interleucina-10/uso terapéutico , Alanina Transaminasa/efectos de los fármacos , Antiinflamatorios no Esteroideos/efectos adversos , Antiinflamatorios no Esteroideos/uso terapéutico , Esquema de Medicación , Femenino , Humanos , Inyecciones Subcutáneas , Interleucina-10/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéuticoRESUMEN
The effect of longeing and glucosamine supplementation on known biological markers of joint disease was studied in yearling quarter horses. Twenty-one yearling quarter horses were randomly assigned to one of 4 treatments: 1) longeing (longeing 20 min daily) supplement control (LN); 2) longeing/glucosamine (LG); 3) walking (mechanical walker for 120 min daily (WN)); and 4) walking/glucosamine (WG). Oral glucosamine was administered at 5.5 g b.i.d. weeks 1-4, 3.5 g b.i.d. during weeks 5-6, and 2.0 g b.i.d. during weeks 7-8. Serum was obtained weekly for 8 wk and analyzed for keratan sulfate and osteocalcin concentrations. Walked horses receiving glucosamine showed slight elevation in serum keratan sulfate compared to controls (P = 0.04). Glucosamine or longeing exercise had no significant effect (6 > or = 0.08) on serum osteocalcin concentrations. Under these conditions, longeing and/or glucosamine supplementation did not significantly alter serum concentrations of keratan sulfate or osteocalcin.
Asunto(s)
Glucosamina/farmacología , Enfermedades de los Caballos/prevención & control , Artropatías/veterinaria , Condicionamiento Físico Animal , Animales , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Femenino , Glucosamina/administración & dosificación , Enfermedades de los Caballos/fisiopatología , Caballos , Artropatías/fisiopatología , Artropatías/prevención & control , MasculinoRESUMEN
The case history of a 40-year-old man who developed systemic metastases 2 years after treatment for glioblastoma is reported. The diagnosis was confirmed by biopsy. The role of immunohistochemistry in the diagnosis of this rare event is discussed and illustrated.