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1.
Dis Esophagus ; 33(2)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31329828

RESUMEN

The aims of this pilot study are to evaluate the feasibility, safety, and effectiveness of conducting an enhanced nutritional support pathway including extended preoperative nutritional support and one month home enteral nutrition (HEN) for patients who underwent enhanced recovery after esophagectomy. We implemented extended preoperative nutritional support and one month HEN after discharge for patients randomized into an enhanced nutrition group and implemented standard nutritional support for patients randomized into a conventional nutrition group. Except the nutritional support program, both group patients underwent the same standardized enhanced recovery after surgery programs of esophagectomy based on published guidelines. Patients were assessed at preoperative day, postoperative day 7 (POD7), and POD30 for perioperative outcomes and nutritional status. To facilitate the determination of an effect size for subsequent appropriately powered randomized clinical trials and assess the effectiveness, the primary outcome we chose was the weight change before and after esophagectomy. Other outcomes including body mass index (BMI), lean body mass (LBM), appendicular skeletal muscle mass index (ASMI), nutrition-related complications, and quality of life (QoL) were also analyzed. The intention-to-treat analysis of the 50 randomized patients showed that there was no significant difference in baseline characteristics. The weight (-2.03 ± 2.28 kg vs. -4.05 ± 3.13 kg, P = 0.012), BMI (-0.73 ± 0.79 kg/m2 vs. -1.48 ± 1.11 kg/m2, P = 0.008), and ASMI (-1.10 ± 0.37 kg/m2 vs. -1.60 ± 0.66 kg/m2, P = 0.010) loss of patients in the enhanced nutrition group were obviously decreased compared to the conventional nutrition group at POD30. In particular, LBM (48.90 ± 9.69 kg vs. 41.96 ± 9.37 kg, p = 0.031) and ASMI (7.56 ± 1.07 kg/m2 vs. 6.50 ± 0.97 kg/m2, P = 0.003) in the enhanced nutrition group were significantly higher compared to the conventional nutrition group at POD30, despite no significant change between pre- and postoperation. In addition, European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 scores revealed that enhanced nutritional support improved the QoL of patients in physical function (75.13 ± 9.72 vs. 68.33 ± 7.68, P = 0.009) and fatigue symptom (42.27 ± 9.93 vs. 49.07 ± 11.33, P = 0.028) compared to conventional nutritional support. This pilot study demonstrated that an enhanced nutritional support pathway including extended preoperative nutritional support and HEN was feasible, safe, and might be beneficial to patients who underwent enhanced recovery after esophagectomy. An appropriately powered trial is warranted to confirm the efficacy of this approach.


Asunto(s)
Vías Clínicas , Recuperación Mejorada Después de la Cirugía , Esofagectomía , Apoyo Nutricional/métodos , Complicaciones Posoperatorias/prevención & control , Cuidados Preoperatorios/métodos , Calidad de Vida , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Composición Corporal , Nutrición Enteral , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Proyectos Piloto , Complicaciones Posoperatorias/epidemiología , Recuperación de la Función , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 50(10): 869-873, 2016 Oct 06.
Artículo en Chino | MEDLINE | ID: mdl-27686764

RESUMEN

Objective: To investigate the number and distribution of N-linked glycosylation sites of simian/human immunodeficiency virus envelope proteins(SHIVSF162P3)and SHIV transmission. Methods: Two female adult Chinese rhesus macaques(4 years old)were intravenously inoculated with 300 TCID50 SHIVSF162P3. The macaques weighed 4 and 5 kg and were identified as Rh1 and Rh2. We collected plasma samples at days 3, 7, 10, 14, 17, 21, 24, 28, 35, 42, 49, 56, 63, 70 and 77 post-challenge. Subsequently, we monitored plasma viral load by real-time PCR after viral RNA isolation and cDNA synthesis. We amplified the full-length envelope gene by single genome amplification(SGA)at days 7, 14, 28 and 77. BioEdit, MEGA, and the HIV Databases were used to analyze envelope sequences. Sequence diversity and N-linked glycosylation sites were compared between virus stock and plasma viruses of the two macaques. Results: A total of 55 env sequences were obtained from virus stock and their average pairwise distances were(0.166 6± 0.096 3)%. Viral loads peaked at 7.68 and 7.49 log10 copies/ml at day 10 and reached the set point at day 42(4.27 and 4.81 log10 copies/ml). The percentages of envelope sequences containing 25 potential N-linked glycosylation sites(PNGSs)were 83%(20/24)and 94%(29/31)in Rh1 and Rh2, respectively, at day 7; these were significantly higher than the proportion in SHIVSF162P3 stock(49%(27/55)). Viral diversity after infection increased with time whereas the proportion of sequences containing 25 PNGSs decreased and sequences containing 27 PNGSs gradually increased. In Rh1, the percentage of sequences containing 27 PNGSs increased to 29% at day 28 and reached 35% at day 77 in Rh2. By analyzing the number of PNGSs in the V1-V5 regions, we found that PNGS variation mainly occurred in the V4 loop. Compared with sequences containing 27 PNGSs, a seven amino acid(TWNNTIG)deletion was found in the V4 loop, which resulted in a loss of two PNGSs at positions 392 and 396. Conclusion: Low glycosylation of the SHIVSF162P3 V4 loop may facilitate spread of the SHIV virus whereas viruses with highly glycosylated V4 loops showed replication advantages after infection.


Asunto(s)
Productos del Gen env/genética , Glicosilación , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Virus de la Inmunodeficiencia de los Simios/genética , Secuencia de Aminoácidos , Animales , Femenino , Genes env , VIH-1/metabolismo , Humanos , Macaca mulatta , Glicoproteínas de Membrana , Datos de Secuencia Molecular , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de Proteína/métodos , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/aislamiento & purificación , Proteínas del Envoltorio Viral , Carga Viral
4.
Mayo Clin Proc ; 91(2): 218-25, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26848003

RESUMEN

Deep brain stimulation (DBS) of the thalamic centromedian/parafascicular (CM-Pf) complex has been reported as a promising treatment for patients with severe, treatment-resistant Tourette syndrome (TS). In this study, safety and clinical outcomes of bilateral thalamic CM-Pf DBS were reviewed in a series of 12 consecutive patients with medically refractory TS, 11 of whom met the criteria of postsurgical follow-up at our institution for at least 2 months. Five patients were followed for a year or longer. Consistent with many patients with TS, all patients had psychiatric comorbidities. Tic severity and frequency were measured by using the Yale Global Tic Severity Scale (YGTSS) over time (average, 26 months) in 10 subjects. One patient was tested at 2-week follow-up only and thus was excluded from group YGTSS analysis. Final YGTSS scores differed significantly from the preoperative baseline score. The average (n=10) improvement relative to baseline in the total score was 54% (95% CI, 37-70); average improvement relative to baseline in the YGTSS Motor tic, Phonic tic, and Impairment subtests was 46% (95% CI, 34-64), 52% (95% CI, 34-72), and 59% (95% CI, 39-78), respectively. There were no intraoperative complications. After surgery, 1 subject underwent wound revision because of a scalp erosion and wound infection; the implanted DBS system was successfully salvaged with surgical revision and combined antibiotic therapy. Stimulation-induced adverse effects did not prevent the use of the DBS system, although 1 subject is undergoing a trial period with the stimulator off. This surgical series adds to the literature on CM-Pf DBS and supports its use as an effective and safe therapeutic option for severe refractory TS.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Complicaciones Posoperatorias/terapia , Dermatosis del Cuero Cabelludo , Tálamo , Síndrome de Tourette , Adolescente , Niño , Preescolar , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Selección de Paciente , Atención Perioperativa/métodos , Estudios Retrospectivos , Dermatosis del Cuero Cabelludo/etiología , Dermatosis del Cuero Cabelludo/terapia , Índice de Severidad de la Enfermedad , Tics/clasificación , Tics/diagnóstico , Tics/terapia , Síndrome de Tourette/diagnóstico , Síndrome de Tourette/fisiopatología , Síndrome de Tourette/terapia , Resultado del Tratamiento
5.
Opt Lett ; 39(9): 2649-51, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24784068

RESUMEN

A diode-pumped actively Q-switched Raman laser employing BaWO4 as the Raman active medium and a ceramic Nd:YAG laser operating at 1444 nm as the pump source is demonstrated. The first-Stokes-Raman generation at 1666 nm is achieved. With a pump power of 20.3 W and pulse repetition frequency rate of 5 kHz, a maximum output power of 1.21 W is obtained, which is the highest output power for a 1.6 µm Raman laser. The corresponding optical-to-optical conversion efficiency is 6%; the pulse energy and peak power are 242 µJ and 8.96 kW, respectively.


Asunto(s)
Transferencia de Energía , Láseres de Estado Sólido , Espectrometría Raman/instrumentación , Cerámica/efectos de la radiación , Diseño de Equipo , Análisis de Falla de Equipo , Dosis de Radiación
6.
Opt Lett ; 38(16): 3075-7, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24104652

RESUMEN

We report on a diode-pumped Nd:YAG ceramic laser operating at 1442.8 nm for the first time. In our experiment, two different Nd:YAG ceramics with the Nd-doped concentrations of 1.0 and 0.6 at. % and a Nd:YAG with the Nd-doped concentration of 1.0 at. % were used as the laser gain mediums, respectively. At a pump power of 20.7 W, a maximum output power of up to 3.96 W with optical-to-optical efficiency of up to 19.1% was obtained by using the 1.0 at. % Nd-doped ceramic as the laser gain medium. To the best of our knowledge, this is the highest output power of a LD-pumped 1.44 µm Nd:YAG ceramic laser and the highest optical-to-optical efficiency of a LD-pumped 1.44 µm Nd-doped crystal laser.


Asunto(s)
Cerámica , Ojo , Rayos Láser , Seguridad
7.
Neuroscience ; 238: 209-17, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23485590

RESUMEN

The transforming growth factor beta-activated kinase 1 (TAK1), a member of the Mitogen-activated protein kinase kinase kinase family, is characterized as a key regulator in inflammatory and apoptosis signaling pathways. The aim of the present study was to evaluate the role of the TAK1 pathway in experimental traumatic brain injury (TBI) in rats. Adult male Sprague-Dawley rats were subjected to TBI using a modified Feeney's weight-drop model. The time course showed that a significant increase of TAK1 and p-TAK1 expression in the cortex after TBI. Moreover, TBI induced TAK1 redistribution both in neurons and astrocytes of the lesion boundary zone. The effects of specific inhibition of the TAK1 pathway by 5Z-7-oxozeaenol (OZ, intracerebroventricular injection at 10min post-trauma) on histopathological and behavioral outcomes in rats were assessed at 24h post injury. The number of TUNEL-positive stained cells was diminished and neuronal survival and neurological function were improved with OZ treatment. Biochemically, the high dose of OZ significantly reduced the levels of TAK1 and p-TAK1, further decreased nuclear factor-κB and activator protein 1 activities and the release of inflammatory cytokines. In addition, we found that both 10min and 3h post-trauma OZ therapies could markedly improve neurological function and neuronal survival after long-term survival. These results revealed that the TAK1 pathway is activated after experimental TBI and the inhibitor OZ affords significant neuro- protection and amelioration of neurobehavioral deficits after experimental TBI, suggesting a potential rationale for manipulating this pathway in clinical practice.


Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Corteza Cerebral/lesiones , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Zearalenona/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/patología , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Neuronas/metabolismo , Neuronas/patología , Fármacos Neuroprotectores/farmacología , Fosforilación , Ratas , Ratas Sprague-Dawley , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Zearalenona/farmacología , Zearalenona/uso terapéutico
8.
J Int Med Res ; 40(4): 1532-45, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22971506

RESUMEN

OBJECTIVE: Since 2007, the use of erythropoiesis-stimulating agents (ESAs) to treat anemia in cancer patients receiving chemotherapy has been increasingly restricted in the USA. This study assessed hemoglobin (Hb) decline over time among chemotherapy patients. METHODS: Episodes of chemotherapy care were identified in a large US-oncology electronic medical record database; weekly Hb levels were computed in the first 8 weeks. Unadjusted and adjusted proportions of patient-weeks with Hb decline>1 g/dl (i.e. representing clinically significant decline) within 1 or 2 weeks were analyzed. RESULTS: Between 2006 and 2009, unadjusted proportions of patient-weeks with Hb decline>1 g/dl increased (1-week, from 12.7% to 14.9%; 2-week, from 19.3% to 26.3%). Adjusted 1-week proportions in 2007 were similar to 2006, but increased in 2008 (odds ratio [OR] 1.135; 95% confidence intervals [CI] 1.067, 1.208) and in 2009 (OR 1.235; 95% CI 1.094, 1.395). Adjusted 2-week proportions had the same pattern. CONCLUSIONS: Since restrictions on ESA use were introduced in the USA, more patients have experienced a clinically significant Hb decline after chemotherapy initiation. Initiating anemia therapy at the earliest indicated opportunity may help reduce the risk of such declines.


Asunto(s)
Anemia/tratamiento farmacológico , Antineoplásicos/efectos adversos , Hematínicos/uso terapéutico , Hemoglobinas/metabolismo , Neoplasias/tratamiento farmacológico , Anciano , Anemia/sangre , Anemia/inducido químicamente , Anemia/epidemiología , Antineoplásicos/uso terapéutico , Femenino , Humanos , Reembolso de Seguro de Salud/legislación & jurisprudencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Estados Unidos/epidemiología , United States Food and Drug Administration/legislación & jurisprudencia
9.
Br J Dermatol ; 165(3): 526-33, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21564055

RESUMEN

BACKGROUND: The full mechanism of action of isotretinoin [13-cis retinoic acid (13-cis RA)] in treating acne is unknown. 13-cis RA induces key genes in sebocytes that are involved in apoptosis, including Tumor necrosis factor Related Apoptosis Inducing Ligand (TRAIL). OBJECTIVES: In this study, we investigated the role of 13-cis RA-induced TRAIL within SEB-1 sebocytes. METHODS: Using 13-cis RA and recombinant human TRAIL (rhTRAIL) protein, we assessed induction of TRAIL and apoptosis in SEB-1 sebocytes, normal keratinocytes and patient skin biopsies. RESULTS: Treatment with rhTRAIL protein increased TUNEL-positive staining in SEB-1 sebocytes. TRAIL siRNA significantly decreased the percentage of TUNEL-positive SEB-1 sebocytes in response to 13-cis RA treatment. Furthermore, TRAIL expression increased in the skin of patients with acne after 1 week of isotretinoin therapy compared with baseline. TRAIL expression localized within sebaceous glands. Unlike sebocytes, TRAIL protein expression was not increased in normal human epidermal keratinocytes in response to 13-cis RA, nor did rhTRAIL induce apoptosis in keratinocytes, suggesting that TRAIL is key in the sebocyte-specific apoptotic effects of 13-cis RA. CONCLUSIONS: Taken together, our data suggest that TRAIL, like the neutrophil gelatinase-associated lipocalin, is involved in mediating 13-cis RA apoptosis of sebocytes.


Asunto(s)
Apoptosis/efectos de los fármacos , Fármacos Dermatológicos/farmacología , Isotretinoína/farmacología , Glándulas Sebáceas/citología , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Acné Vulgar/tratamiento farmacológico , Acné Vulgar/metabolismo , Acné Vulgar/patología , Proteínas de Fase Aguda/metabolismo , Células Cultivadas , Humanos , Etiquetado Corte-Fin in Situ , Lipocalina 2 , Lipocalinas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , ARN Interferente Pequeño/farmacología , Proteínas Recombinantes/farmacología , Glándulas Sebáceas/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Transfección
10.
Br J Dermatol ; 165(2): 302-10, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21466536

RESUMEN

BACKGROUND: A clear-cut need exists for safe and effective alternatives to the use of isotretinoin in severe acne. Lack of data regarding the specifics of isotretinoin's mechanism of action has hampered progress in this area. Recently, the protein neutrophil gelatinase-associated lipocalin (NGAL) has been identified as a mediator of the apoptotic effect of isotretinoin on sebocytes. OBJECTIVES: To establish further the clinical relevance of NGAL and to elucidate the factors that induce NGAL expression in sebocytes. METHODS: Methods were developed to isolate and quantify skin-surface levels of NGAL from normal subjects and patients with acne undergoing treatment with isotretinoin. RESULTS: Patients with acne were found to have higher skin levels of NGAL compared with normal subjects. Studies in SEB-1 sebocytes indicate that NGAL expression is increased in response to Propionibacterium acnes and interleukin (IL)-1ß. In patients, isotretinoin increases NGAL levels by 2·4-fold on the skin surface and this increase precedes decreases in sebum and P. acnes counts. CONCLUSIONS: These data support the hypothesis that NGAL is an important mediator of the early effects of isotretinoin on the sebaceous glands and provide insights into the mechanisms that regulate NGAL expression in the skin.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Proteínas de Fase Aguda/metabolismo , Fármacos Dermatológicos/uso terapéutico , Isotretinoína/uso terapéutico , Lipocalinas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Piel/metabolismo , Acné Vulgar/metabolismo , Adolescente , Adulto , Células Cultivadas , Estudios de Cohortes , Ensayo de Inmunoadsorción Enzimática , Humanos , Interleucina-1beta/farmacología , Interleucina-8/metabolismo , Lipocalina 2 , Propionibacterium acnes/aislamiento & purificación , Propionibacterium acnes/metabolismo , Glándulas Sebáceas/citología , Glándulas Sebáceas/metabolismo , Piel/microbiología , Adulto Joven
11.
J Anim Sci ; 87(3): 1085-96, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19098244

RESUMEN

The effects of 3 nonionic surfactants (NIS), including alkyl polyglucoside (APG), sorbitan trioleate (Span85), and polyoxyethylene sorbitan monostearate (Tween80), on in vitro fermentation characteristics of maize stover, rice straw, and wheat straw were examined using an in vitro gas production technique. Four levels each of APG, Span85, and Tween80 [0, 0.02, 0.05, and 0.1% (vol/vol) of incubation solution] were tested in a 4 x 4 x 4 factorial arrangement. The NIS generally increased the in vitro maximal gas production (A), but decreased the lag time of cereal straws. The effects of NIS on the rate of gas production (B) were related to the surfactant type and fermented substrate. The NIS generally increased IVDMD and in vitro OM disappearance (IVOMD) of cereal straws, but responses were dose dependent. The NIS increased total VFA concentration of in vitro fermentation supernatant for maize stover and wheat straw, but decreased total VFA concentration for rice straw. The effects of NIS on the molar proportions of acetate, propionate, and butyrate were dependent on the dose and type of NIS and on fermented substrate. Several interactive effects were noted between or among 3 surfactants (APG, Span85, and Tween80) on in vitro gas production variables, IVD-MD, IVOMD, and VFA for each straw; the optimal combinations of 2 or 3 types of NIS were determined according to the responses of IVDMD and IVOMD to NIS addition. The results of this study suggest that NIS may improve in vitro fermentation of low quality roughages and have potential application as feed additives in ruminant production.


Asunto(s)
Grano Comestible/metabolismo , Fermentación/efectos de los fármacos , Tensoactivos/farmacología , Animales , Grano Comestible/química , Ácidos Grasos Volátiles/análisis , Gases/metabolismo , Cabras , Hexosas/farmacología , Polisorbatos/farmacología , Rumen/metabolismo
12.
Arch Environ Contam Toxicol ; 52(2): 153-62, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17165108

RESUMEN

Previous literature has reported the fate of persistent organic pollutants (POPs) in mountainous regions, but the Himalayas have received little attention, and few results from this region have been published. The present study collected soil and grass samples from the Mt. Qomolangma (Everest) area, central Himalayas, China, from the elevation range 4700 to 5620 m. We analyzed all samples for organochlorine pesticides (OCPs) to determine the level of OCP contamination in the Qomolangma region. The soil samples contained 0.385 to 6.06 ng g(-1) of DDT only, and these concentrations were lower than those from Europe and mountains close to industrial emissions. Our study detected a number of OCPs in the grass samples, such as hexachlorocyclohexane (HCH) (0.354 to 7.82 ng g(-1)), hexachlorobenzene (HCB) (0.0156 to 1.25 ng g(-1)), endosulfan (0.105 to 3.14 ng g(-1)), and DDT components (1.08 to 6.99 ng g(-1)). Their concentrations were higher than those in pine needles from Alberta, Canada. Our measurements of HCH and DDT in grass samples showed the same or slightly higher concentration levels than reported in moss from Mt. Qomolangma 15 years ago. This result and the analysis of isomer ratios (alpha/gamma-HCH and p-p'-DDE/p-p'-DDT) indicate recent releases of OCPs from a nearby region, possibly from dicofol use in India. We also investigated the elevation distribution of OCPs and found that HCH and HCB were progressively concentrated in colder, higher elevation sites. A bioconcentration factor (BCF) of grass was calculated, and the BCF values increased with the increasing elevation, indicating that the cold condensation of POPs at high-elevation sites may increase the potential threat to vegetation and the food chain in the mountain ecosystem.


Asunto(s)
Altitud , Monitoreo del Ambiente/estadística & datos numéricos , Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Poaceae/química , Suelo/análisis , China , Cromatografía de Gases , Nieve/química
14.
J Biomed Mater Res ; 55(1): 28-32, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11426394

RESUMEN

Twenty-one porous hydroxyapatite-tricalcium phosphate ceramic cylinders 1.5 cm long and 1.2 cm in diameter were swathed with fresh autogenetic periostea taken from 21 dogs and implanted in the same animals' muscles to get living ceramic bone substitutes. These substitutes contained autogenetic growth stimulators including osteoblasts and other multipotential cells. One month later, they were transferred to the segmental bone defect sites created in femoral diaphysis of the same animals. The roentgenograms showed that in time the boundaries between the cylinders and bone sections became vague. X-ray diffraction analysis indicated that the spectra of the samples tended to be similar to those of natural bones by 6 months postoperatively. Their bending strengths also increased gradually. After the cylinders were transferred from muscles to the bone defect sites, newly formed bone tissues rapidly increased and the cylinders gradually fused with the contacted bones 2 months later. By 4 and 6 months, bone tissue occupied most areas of the materials. The ratio of newly formed bone tissue had a large lead over the materials. Haversian systems were clearly observed and matured bone tissues filled the ceramic pores and connected with each other. Results suggested that culturing complexes that consist of autogenetic periostea and biomaterials, taking advantage of living organic culturing medium, should be an effective approach to get satisfactory bioactive bone substitutes. It also provides a basis for clinically repairing bone defects in bearing sites with complex bioceramics.


Asunto(s)
Sustitutos de Huesos , Huesos/fisiología , Cerámica , Fémur/cirugía , Osteoblastos/citología , Periostio/fisiología , Animales , Sustitutos de Huesos/química , Huesos/citología , Fosfatos de Calcio/química , División Celular , Cerámica/química , Perros , Durapatita/química , Masculino , Periostio/trasplante , Trasplante Autólogo , Difracción de Rayos X
15.
Wei Sheng Yan Jiu ; 30(6): 326-8, 2001 Nov.
Artículo en Chino | MEDLINE | ID: mdl-12561609

RESUMEN

Synthetic hydroxyapatite was used as a material for the defluoridation of drinking water. The defluoridation capacity, regeneration the capability of defluoridator and the corresponding parameters of defluoridation and regeneration have been studied with batch and column test. The results showed that the defluoridation capacity of synthetic hydroxyapatite on F- was 3.7-4.3 mg/g in batch test, 5.6 mg/g for break through (1.0 mg/L is considered as the break through point) in column test, and 10.7 mg/g for saturation in column test. The efficiency of regeneration was 46%-64% for saturated hydroxyapatite with surface-coating method.


Asunto(s)
Fluoruros/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Abastecimiento de Agua/análisis , Durapatita
16.
J Invest Dermatol ; 115(4): 614-9, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10998132

RESUMEN

Melanocortins regulate pigmentation, adrenal hormone secretion, immune functions, lipid metabolism, and feeding behaviors in rodents. These peptides include adrenocorticotrophic hormone, melanocyte stimulating hormone, beta-lipotrophin, and the endorphins. Lipid metabolism in sebaceous glands and preputial glands of rodents is regulated by alpha-melanocyte stimulating hormone, the major agonist for melanocortin receptors. Five melanocortin receptor subtypes have been identified that differ in their tissue localization and affinities for melanocortin ligands. Targeted disruption of the melanocortin 5 receptor in transgenic mice results in widespread dysfunction of exocrine glands, including a marked decrease in sebum production. A role for melanocortins in the modulation of human sebum production has not been established. The goal of this study is to determine which melanocortin receptors are expressed in human sebaceous glands. Messenger RNA was isolated from human sebaceous glands and the reverse transcriptase polymerase chain reaction was performed using primers specific for each of the melanocortin receptor subtypes. Transcripts were detected for the melanocortin 5 receptor. A polyclonal chicken antihuman antibody to the melanocortin 5 receptor localized to sebaceous glands, eccrine glands, hair follicles, and epidermis in human skin, rat skin, cultured human sebocytes, and rat preputial cells. Presence of the melanocortin 5 receptor protein in human sebaceous glands and rat preputial glands was further verified by Western blotting. These data support further investigation of the role of melanocortins in the regulation of human sebum production and support the use of the rat preputial system as an experimental model in sebaceous gland physiology.


Asunto(s)
Pene/citología , Receptores de Corticotropina/biosíntesis , Glándulas Sebáceas/metabolismo , Animales , Especificidad de Anticuerpos , Western Blotting , Humanos , Inmunohistoquímica , Masculino , Pene/química , Ratas , Receptores de Corticotropina/genética , Receptores de Corticotropina/inmunología , Receptores de Melanocortina , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Glándulas Sebáceas/química , Sebo/metabolismo , Transcripción Genética
17.
J Biomed Mater Res ; 52(2): 354-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10951375

RESUMEN

Twenty-one dogs were used to study the osteoinductivity and biomechanical properties of a biphasic porous ceramic with autogenic periosteum implanted in muscle. The ceramic implants were swathed in fresh periosteum derived from the same animals and implanted in the femur muscles. The other two groups of animals served as controls using the same material implanted in the femur bones and muscles without periosteum. Biomechanical measurements showed that, in the muscles, the experimental group had a higher bending strength than the unswathed group by the time the samples were harvested. Six months postoperatively, the strength of the samples in the experimental group had almost reached that of normal bones. The results of X-ray diffraction and infrared spectrometric analysis suggested that the degradation rate and speed of tricalcium phosphate (TCP) of the ceramic in the experimental group were faster than in the unswathed samples, but slower than in samples implanted in bones. The bone replacement and bone-inducing activity were excellent in the periosteum-swathed samples. Histologically, satisfactory bone repair was seen in the experimental samples. All results indicate that autogenic periosteum could increase bioactivity of ceramics in heterosites and improve bone formation in the surroundings of porous calcium phosphate ceramics. The data also infer that the complicated procedure of culturing bone growth factors with biomaterials in vitro to obtain bioactive grafts could be replaced by this relatively simple method.


Asunto(s)
Sustitutos de Huesos , Cerámica , Periostio , Animales , Fenómenos Biomecánicos , Perros , Elasticidad , Masculino
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 22(1): 71-4, 2000 Feb.
Artículo en Chino | MEDLINE | ID: mdl-12903498

RESUMEN

OBJECTIVE: To observe the characteristic immunodeficiency syndrome of the rapid fatal type of simian immunodeficiency virus (SIV) infected monkeys. METHODS: Eighty rhesus monkeys and 4 cynomolgus monkeys were intravenously inoculated with SIVmac or SIVmac251. The virus isolation and viral titer, estimation by indirect immunofluroresence and viral antibody were determined periodically from monkeys' plasma; lymph node biopsies were performed for pathohistological examination. RESULTS: Twelve out of 84 macaque (14.2%) died of rapid progressive type after inoculation of SIVmac and SIVmac251 in the duration 3 to 4 months. Dying monkeys showed persistent high viremia and low level titre antibody. Eight of 10 pathohistological changes showed severe depletion of lymphoid tissue in spleen and lymph nodes, there were remarkable immunodeficiency with opportunity infection. The other two monkeys appeared moderate lymphoid tissue deletion and hyperplasia without opportunity infections. The survived monkeys' (72/84) lymph nodes biopsies revealed hypoplasia of lymphoid tissue. CONCLUSIONS: The characteristic immunodeficiency syndrome of rapid fatal type of simian immunodeficiency virus infected monkeys could be made with persistent high viremia, low level antibody, severe lymphoid tissue deletion in lymph nodes and spleen, as well as complicated opportunity infections.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida del Simio , Enfermedad Aguda , Animales , Modelos Animales de Enfermedad , Femenino , Macaca fascicularis , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología
19.
Zhongguo Yao Li Xue Bao ; 13(4): 380-4, 1992 Jul.
Artículo en Chino | MEDLINE | ID: mdl-1456068

RESUMEN

The influence of hyperthyroidism on the action of drugs affecting rat liver glycogen content and its mechanism were investigated. The thyroid-induced hyperthyroidism of rat served as the model. In normal rats, dexamethasone (5 mg.kg-1, ip) increased the content of liver glycogen and decreased the Bmax of glucocorticoid receptors (GCR) in liver cytosol. These effects were minimized or even disappeared in hyperthyroid rat models. On the other hand, in normal rats, epinephrine (0.20 mg.kg-1, ip) decreased the content of liver glycogen. This effect was potentiated in hyperthyroid rat models. Epinephrine did not affect the Bmax of GCR in liver cytosol of normal and hyperthyroid rats. These results suggested that hyperthyroidism may be one of the causes effecting the individual differences of drug action, and that the influence of hyperthyroidism on the glycogen-increasing action of dexamethasone correlated well with the changes in glucocorticoid receptor. The mechanism of the influence of hyperthyroidism on the glycogen-decreasing action of epinephrine is to be further explored.


Asunto(s)
Dexametasona/farmacología , Epinefrina/farmacología , Glucógeno/metabolismo , Hipertiroidismo/metabolismo , Hígado/metabolismo , Receptores de Glucocorticoides/efectos de los fármacos , Animales , Citosol/metabolismo , Masculino , Consumo de Oxígeno , Ratas , Ratas Wistar
20.
Zhongguo Yao Li Xue Bao ; 13(2): 139-42, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1317986

RESUMEN

D-galactosamine (Gal 0.5 mmol.L-1) made lactate dehydrogenase (LDH) leakage from the hepatocytes in monolayer-culture increase by 50%, Dimethyl sulfoxide (Me2SO 2% vol/vol) decreased the LDH leakage (P less than 0.05). The cytosolic free Ca2+ concentration ([Ca2+]c) of rat hepatocytes exposed to Gal 4 mmol.L-1 for 90 min in suspension culture increased about 2-fold (P less than 0.01). Me2SO (2%) antagonized this [Ca2+]c-increasing effect of Gal. These results verified directly that the [Ca2+]c of hepatocytes was increased in the early stage of Gal-induced hepatotoxicity, and suggested that the prevention or lightening of the disturbance in intracellular Ca2+ homeostasis may be, at least, one of the mechanisms of the protective action of Me2SO against Gal-induced hepatocyte injury.


Asunto(s)
Calcio/metabolismo , Dimetilsulfóxido/farmacología , Hígado/citología , Animales , ATPasas Transportadoras de Calcio/fisiología , Células Cultivadas , Citosol/metabolismo , Galactosamina/farmacología , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas
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