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1.
Cartilage ; 13(1): 19476035221085146, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35354310

RESUMEN

OBJECTIVE: To evaluate the clinical outcome of a hydrogel-based autologous chondrocyte implantation (ACI) for large articular cartilage defects in the knee joint. DESIGN: Prospective, multicenter, single-arm, phase III clinical trial. ACI was performed in 100 patients with focal full-thickness cartilage defects ranging from 4 to 12 cm2 in size. The primary outcome measure was the responder rate at 2 years using the Knee Injury and Osteoarthritis Outcome Score (KOOS). RESULTS: Two years after ACI treatment, 93% of patients were KOOS responders having improved by ≥10 points compared with their pre-operative level. The primary endpoint of the study was met and demonstrated that the KOOS response rate is markedly greater than 40% with a lower 95% CI (confidence interval) of 86.1, more than twice the pre-specified no-effect level. KOOS improvement (least squares mean) was 42.0 ± 1.8 points (95% CI between 38.4 and 45.7). Mean changes from baseline were significant in the overall KOOS and in all 5 KOOS subscores from Month 3 (first measurement) to Month 24 (inclusive) (P < 0.0001). The mean MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score after 24 months reached 80.0 points (95% CI: 70.0-90.0 points) and 92.1 points in lesions ≤ 5 cm2. CONCLUSIONS: Overall, hydrogel-based ACI proved to be a valuable treatment option for patients with large cartilage defects in the knee as demonstrated by early, statistically significant, and clinically meaningful improvement up to 2 years follow-up. Parallel to the clinical improvements, MRI analyses suggested increasing maturation, re-organization, and integration of the repair tissue. TRIAL REGISTRATION: NCT03319797; EudraCT No.: 2016-002817-22.


Asunto(s)
Cartílago Articular , Condrocitos , Cartílago Articular/cirugía , Humanos , Hidrogeles/uso terapéutico , Articulación de la Rodilla/cirugía , Estudios Prospectivos , Trasplante Autólogo/métodos
3.
Cell Mol Life Sci ; 61(9): 1025-41, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15112051

RESUMEN

Misfolded or incompletely assembled multisubunit glycoproteins undergo endoplasmic reticulum-associated degradation (ERAD) regulated in large measure by their N-linked polymannose oligosaccharides. In this quality control system lectin interaction with Glc(3)Man(9)GlcNAc(2) glycans after trimming with endoplasmic reticulum (ER) alpha-glucosidases and alpha-mannosidases sorts out persistently unfolded glycoproteins for N-deglycosylation and proteolytic degradation. Monoglucosylated (Glc(1)Man(9)GlcNAc(2)) glycoproteins take part in the calnexin/calreticulin glucosylation-deglucosylation cycle, while the Man(8)GlcNAc(2) isomer B product of ER mannosidase I interacts with EDEM. Proteasomal degradation requires retrotranslocation into the cytosol through a Sec61 channel and deglycosylation by peptide: N-glycosidase (PNGase); in alternate models both PNGase and proteasomes may be either free in the cytosol or ER membrane-imbedded/attached. Numerous proteins appear to undergo nonproteasomal degradation in which deglycosylation and proteolysis take place in the ER lumen. The released free oligosaccharides (OS) are transported to the cytosol as OS-GlcNAc(2) along with similar components produced by the hydrolytic action of the oligosaccharyltransferase, where they together with OS from the proteasomal pathway are trimmed to Man(5)GlcNAc(1) by the action of cytosolic endo-beta- N-acetylglucosaminidase and alpha-mannosidase before entering the lysosomes. Some misfolded glycoproteins can recycle between the ER, intermediate and Golgi compartments, where they are further processed before ERAD. Moreover, properly folded glycoproteins with mannose-trimmed glycans can be deglucosylated in the Golgi by endomannosidase, thereby releasing calreticulin and permitting formation of complex OS. A number of regulatory controls have been described, including the glucosidase-glucosyltransferase shuttle, which controls the level of Glc(3)Man(9)GlcNAc(2)-P-P-Dol, and the unfolded protein response, which enhances synthesis of components of the quality control system.


Asunto(s)
Retículo Endoplásmico/metabolismo , Glicoproteínas/metabolismo , Mananos/metabolismo , Oligosacáridos/metabolismo , Animales , Asparagina/metabolismo , Aparato de Golgi/metabolismo , Humanos , Lectinas/metabolismo , Procesamiento Proteico-Postraduccional/fisiología , Transporte de Proteínas/fisiología
4.
Aviat Space Environ Med ; 74(3): 260-5, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12650274

RESUMEN

BACKGROUND: An essential element in planning for long-term space missions is prediction of the medical support required. Medical data for analogous populations serving in isolated and/or contained environments are useful in predicting health risks for astronauts. METHODS: This study evaluated the rates of health events that occurred among a highly screened, healthy military population during periods of isolation using a centralized database of medical encounter records from U.S. Navy submarines. The study population was composed of U.S. Navy officers and enlisted men deployed on 240 submarine patrols between 1 January 1997 and 30 September 2000. RESULTS: A total of 1389 officers and 11,952 enlisted crew members served aboard participating submarines for 215,086 and 1,955,521 person-days at sea, respectively, during the study period. Officers had 214 initial visits to medical staff with 79 re-visits for the same condition during these patrols, while enlisted men had 3345 initial visits and 1549 re-visits. Among officers, the most common category of medical events was respiratory illnesses (primarily upper respiratory infections), followed by injury, musculoskeletal conditions, infectious diseases, symptoms and ill-defined conditions, and skin problems. Among enlisted men, the most common category of medical events was injury, followed by respiratory illnesses (upper respiratory infections), skin problems, symptoms and ill-defined conditions, digestive disorders, infectious conditions, sensory organ problems (ear infections and eye problems), and musculoskeletal conditions. CONCLUSIONS: Potential mission-impacting medical events reported were rare, i.e., among a crew of seven officers, only one medical event would be expected to occur during a 6-mo mission and result in 3/4 d or less of limited or no duty. Among a crew of seven enlisted men, about two medical events would be expected during a 6-mo mission and result in about 1 d of limited or no duty per medical event.


Asunto(s)
Servicios de Salud/estadística & datos numéricos , Estado de Salud , Personal Militar/psicología , Vuelo Espacial , Adulto , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades Respiratorias/epidemiología , Medición de Riesgo , Navíos , Aislamiento Social
5.
Glycobiology ; 11(10): 803-11, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11588156

RESUMEN

To further explore the localization of the N-deglycosylation involved in the endoplasmic reticulum (ER)-associated quality control system we studied HepG2 cells infected with vesicular stomatitis virus (VSV) and its ts045 mutant, as in this system oligosaccharide release can be attributed solely to the VSV glycoprotein (G protein). We utilized the restricted intracellular migration of the mutant protein as well as dithiothreitol (DTT), low temperature, and a castanospermine (CST)-imposed glucosidase blockade to determine in which intracellular compartment deglycosylation takes place. Degradation of the VSV ts045 G protein was considerably greater at the nonpermissive than at the permissive temperature; this was reflected by a substantial increase in polymannose oligosaccharide release. Under both conditions these oligosaccharides were predominantly in the characteristic cytosolic form, which terminates in a single N-acetylglucosamine (OS-GlcNAc(1)); this was also the case in the presence of DTT, which retains the G protein completely in the ER. However when cells infected with the VSV mutant were examined at 15 degrees C or exposed to CST, both of which represent conditions that impair ER-to-cytosol transport, the released oligosaccharides were almost exclusively (> 95%) in the vesicular OS-GlcNAc(2) form; glucosidase blockade had a similar effect on the wild-type virus. Addition of puromycin to glucosidase-inhibited cells resulted in a pronounced reduction (> 90%) in oligosaccharide release, which reflected a comparable impairment in glycoprotein biosynthesis and indicated that the OS-GlcNAc(2) components originated from protein degradation rather than hydrolysis of oligosaccharide lipids. Our findings are consistent with N-deglycosylation of the VSV G protein in the ER and the subsequent transport of the released oligosaccharides to the cytosol where OS-GlcNAc(2) to OS-GlcNAc(1) conversion by an endo-beta-N-acetylglucosaminidase takes place. Studies with the ts045 G protein at the nonpermissive temperature permitted us to determine that it can be processed by Golgi endomannosidase although remaining endo H sensitive, supporting the concept that it recycles between the ER and cis-Golgi compartments.


Asunto(s)
Retículo Endoplásmico/metabolismo , Glicoproteínas/metabolismo , Mananos/metabolismo , Glicoproteínas de Membrana , Virus de la Estomatitis Vesicular Indiana/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Línea Celular , Cromatografía en Capa Delgada , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Glicósido Hidrolasas/antagonistas & inhibidores , Glicosilación , Humanos , Hidrólisis , Puromicina/farmacología , Temperatura
6.
Anat Rec ; 263(4): 388-95, 2001 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-11500816

RESUMEN

The availability of recombinant osteoinductive growth factors and new osteoconductive matrices offers an alternative to the use of autogenous bone (autograft) for grafting indications. This study evaluates the bone-forming activity of a mineralized collagen matrix combined with recombinant human growth and differentiation factor-5 in a rabbit posterolateral spinal fusion model. The activity of three distinct matrix-growth factor formulations is assessed by radiographic, histologic, and mechanical strength methods. Results show that the radiographic density, histologic quality, and mechanical strength of fusion at 12 weeks post-treatment rank consistently within the treatment groups. Optimal formulations are shown to perform similar to autograft in both the rate and strength of fusion. Fusion rates as high as 80% are observed within specific matrix/growth factor formulations. The average biomechanical strength of treated motion segments in the most efficacious formulation is 82% higher than that obtained with autograft, although this difference is not statistically significant. The fusion mass formed in response to matrix/growth factor formulations is composed of normal trabecular bone with a thin outer cortical plate and modest hematopoietic bone marrow. These results demonstrate that the combination of a mineralized collagen matrix with recombinant human growth and differentiation factor-5 maximizes the inherent conductive and inductive properties of each component, respectively, to provide an effective alternative to autograft for bone grafting procedures.


Asunto(s)
Proteínas Morfogenéticas Óseas , Colágeno/administración & dosificación , Sustancias de Crecimiento/administración & dosificación , Osteogénesis/efectos de los fármacos , Proteínas Recombinantes/administración & dosificación , Fusión Vertebral/métodos , Animales , Trasplante Óseo , Bovinos , Fuerza Compresiva , Curación de Fractura/efectos de los fármacos , Factor 5 de Diferenciación de Crecimiento , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/cirugía , Masculino , Ensayo de Materiales , Conejos
7.
J Clin Oncol ; 19(10): 2616-25, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11352953

RESUMEN

PURPOSE: Controversy exists over the ability of morphology to predict the biologic behavior of Hürthle cell carcinoma. The aim of this study was to conduct a critical histopathologic review of Hürthle cell carcinoma and to correlate morphologic parameters with clinical outcome. PATIENTS AND METHODS: Patients with histologically confirmed Hürthle cell carcinoma treated between 1940 and 2000 form the basis of this study. Adenomas were excluded. Tumors of unknown malignant behavior ([UMB] n = 17) had solid growth pattern, incomplete capsular invasion (Ci), or both but no vascular invasion (Vi). Minimally invasive carcinomas ([MIC] n = 23) had one focus of intra- or extracapsular Vi, one focus of complete Ci, or both. Widely invasive carcinomas ([WIC] n = 33) demonstrated more than one focus of Vi, more than one focus of Ci, or both. The primary end points were relapse-free survival (RFS) and disease-specific survival (DSS). Rates of recurrence/death were estimated by Kaplan-Meier method. The univariate influence of prognostic factors on end points was analyzed by log-rank test, and multivariate analysis was performed by Cox regression. RESULTS: Median follow-up was 8 years. No patients with UMB or MIC relapsed or died of disease. Of WIC, 73% relapsed and 55% died of disease. Age, size, and extent of resection did not influence outcome. Adverse predictors of RFS and DSS among WIC were extrathyroidal extension, nodal metastasis, positive margin, and solid growth pattern (P <.05). Both Ci and Vi were associated with worse DSS (P <.05). On multivariate analysis, extrathyroidal extension and nodal metastases were independent predictors of outcome (P <.05). CONCLUSION: Patients with Hürthle cell carcinoma have a prognosis that is predicted by well-defined histomorphologic characteristics. Unlike differentiated thyroid cancer, nodal metastases predict a worse outcome in widely invasive Hürthle cell carcinoma, as does extrathyroidal extension.


Asunto(s)
Carcinoma/patología , Neoplasias de la Tiroides/patología , Carcinoma/clasificación , Carcinoma/mortalidad , Carcinoma/terapia , Terapia Combinada , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Sistema de Registros , Estudios Retrospectivos , Neoplasias de la Tiroides/clasificación , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/terapia
8.
Mol Biol Cell ; 11(12): 4227-40, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11102520

RESUMEN

Trimming of N-linked oligosaccharides by endoplasmic reticulum (ER) glucosidase II is implicated in quality control of protein folding. An alternate glucosidase II-independent deglucosylation pathway exists, in which endo-alpha-mannosidase cleaves internally the glucose-substituted mannose residue of oligosaccharides. By immunogold labeling, we detected most endomannosidase in cis/medial Golgi cisternae (83.8% of immunogold labeling) and less in the intermediate compartment (15.1%), but none in the trans-Golgi apparatus and ER, including its transitional elements. This dual localization became more pronounced under 15 degrees C conditions indicative of two endomannosidase locations. Under experimental conditions when the intermediate compartment marker p58 was retained in peripheral sites, endomannosidase was redistributed to the Golgi apparatus. Double immunogold labeling established a mutually exclusive distribution of endomannosidase and glucosidase II, whereas calreticulin was observed in endomannosidase-reactive sites (17.3% in intermediate compartment, 5.7% in Golgi apparatus) in addition to the ER (77%). Our results demonstrate that glucose trimming of N-linked oligosaccharides is not limited to the ER and that protein deglucosylation by endomannosidase in the Golgi apparatus and intermediate compartment additionally ensures that processing to mature oligosaccharides can continue. Thus, endomannosidase localization suggests that a quality control of N-glycosylation exists in the Golgi apparatus.


Asunto(s)
Retículo Endoplásmico/enzimología , Glucosa/metabolismo , Aparato de Golgi/enzimología , Lectinas de Unión a Manosa , Manosidasas/metabolismo , Animales , Proteínas de Unión al Calcio/metabolismo , Calreticulina , Compartimento Celular , Línea Celular , Retículo Endoplásmico/ultraestructura , Glicosilación , Aparato de Golgi/ultraestructura , Hígado/enzimología , Manosidasas/inmunología , Proteínas de la Membrana/metabolismo , Microscopía Fluorescente , Microscopía Inmunoelectrónica , Procesamiento Proteico-Postraduccional , Ratas , Ribonucleoproteínas/metabolismo , alfa-Glucosidasas/metabolismo
9.
Glycobiology ; 10(11): 1235-42, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11087716

RESUMEN

The occurrence of sulfate substituents on several positions of glycoprotein N-linked oligosaccharides prompted us to determine the subcellular localization and temporal relationships of the addition of these anionic groups employing as a model system the hemagglutinin (HA) produced by influenza virus-infected Madin-Darby canine kidney (MDCK) cells. It became apparent from a study of the HA glycoprotein in subcellular fractions resolved by Nycodenz gradient centrifugation following pulse-chase radiolabeling that sulfation of the complex N-linked oligosaccharides occurs only after they have been processed to an endo-beta-N-acetylglucosaminidase-resistant state and have reached the medial/trans Golgi and the trans Golgi network (TGN), with the former carrying out most of the sulfation activity. Hydrazine/nitrous acid/NaBH(4) treatment of the HA from the subcellular fractions indicated that C-3 of the galactose as well as C-6 of the N-acetylglucosamine residues of the N-acetyllactosamine chains became sulfated in these post ER fractions, as did the C-6 of the outer N-acetylglucosamine of the di-N-acetylchitobiose core. Consistent with the specificities of the stepwise assembly of the N-acetyllactosamine branches, we observed that the 3'-phosphoadenosine 5'-phosphosulfate (PAPS):GlcNAc-6-O-sulfotransferase migrated in the gradient to a medial/trans Golgi position while in contrast the PAPS:Gal-3-O-sulfotransferase was found in both Golgi and TGN locations. In accordance with the concept that beta-galactosylation must precede the sulfation catalyzed by the latter enzyme, we observed the presence of UDP-Gal:GlcNAc galactosyltransferase in both these sites in the MDCK cells. The presence of the Gal-3-O-sulfotransferase in the TGN is particularly important in the influenza virus-infected cells, as it makes possible the addition of terminal anionic groups after removal of the sialic acid residues by the viral neuraminidase.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Animales , Sitios de Unión , Línea Celular , Perros , Galactosiltransferasas/metabolismo , Glicosilación , Aparato de Golgi/enzimología , Aparato de Golgi/virología , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Oligosacáridos/química , Orthomyxoviridae/química , Orthomyxoviridae/enzimología , Sulfatos/química , Sulfotransferasas/metabolismo
10.
Ann Surg Oncol ; 7(9): 696-704, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11034249

RESUMEN

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) of the head and neck is a rare, locally infiltrative, low-grade sarcoma. This study defines the clinical behavior of DFSP, evaluates the role of frozen section analysis, and identifies factors that predict local control. METHODS: Hospital records and pathological slides were reviewed for 33 patients with pathologically confirmed head and neck DFSP treated at Memorial Sloan-Kettering Cancer Center between 1964 and 1999. Factors were analyzed by using Fisher's exact or chi2 tests. RESULTS: For 21 primary and 12 recurrent patients, median age and tumor size at presentation was 39 years and 2.0 cm, respectively. Thirty-two (97%) patients were alive at a median follow-up of 82 months. Three patients recurred locally, all with smaller than 2-cm resection margins. Deep tumors were more likely to have a margin-positive resection than superficial lesions (P = .03). Gross margin 2 cm or more was a significant predictor of a negative histological margin (P<.001). There was a trend toward improved recurrence-free survival for tumors treated with wide (> or =2 cm) margin resection (P = .059). Accuracy, sensitivity, specificity, and false negative rates of frozen section were 80%, 43%, 100%, and 57%, respectively. CONCLUSIONS: Wide margin resection of head and neck DFSP predicts negative histological margins and impacts favorably on local recurrence-free survival. Frozen section analysis does not assess resection margins accurately.


Asunto(s)
Dermatofibrosarcoma/patología , Neoplasias de Cabeza y Cuello/patología , Neoplasias Cutáneas/patología , Adulto , Anciano , Dermatofibrosarcoma/mortalidad , Dermatofibrosarcoma/cirugía , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Secciones por Congelación , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Registros Médicos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/cirugía
11.
Diabetologia ; 43(8): 1056-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10990084

RESUMEN

AIMS/HYPOTHESIS: Heparan sulphate proteoglycan is an important component of the glomerular anionic filtration barrier and its reduced amount in diabetes contributes to glomerular dysfunction. The objective of this study was to determine if there is also an alteration in the sulphation pattern of the diabetic heparan sulphate chains. METHODS: The heparan sulphate in the glomerular basement membrane/mesangial matrix from human diabetic and nondiabetic kidneys obtained at autopsy was fragmented by a hydrazine/nitrous acid procedure and after radiolabelling with NaB[3H]4, the disaccharide products were chromatographically resolved and quantified. RESULTS: Six sulphated disaccharides were identified in both the diabetic and nondiabetic samples and the molar distribution of these was similar, with the notable exception of the iduronic acid-2-O-sulphatectl--> 4glucosamine-3-O-sulphate species which occurred in the diabetic glomeruli in less than half the amount as in the nondiabetic samples (9.0% compared to 18.7% of total sulphated disaccharides, p < 0.005). CONCLUSION/INTERPRETATION: 3-O-sulphated glucosamine is a rare constituent of heparan sulphate occurring usually in a glucuronic acidbeta1--> 4glucosamine-3-O-sulphate(+/- 6-O-sulphate) sequence within the antithrombin-binding domain. In the glomerular basement membrane where the 3-O-sulphated glucosamine is present in substantial amounts, however, it occurs exclusively in an iduronic acid-containing sequence. It is likely that the recently discovered 3-O-sulphotransferase variant which specifically acts on the iduronic acidalpha1--> 4glucosamine sequence is decreased in human diabetes and moreover that this unusual disaccharide could be a component of a specific heparan sulphate domain which interacts with bioactive proteins.


Asunto(s)
Diabetes Mellitus/metabolismo , Proteoglicanos de Heparán Sulfato/química , Heparitina Sulfato/química , Glomérulos Renales/patología , Anciano , Anciano de 80 o más Años , Autopsia , Membrana Basal/química , Membrana Basal/metabolismo , Membrana Basal/patología , Diabetes Mellitus/patología , Disacáridos/química , Proteoglicanos de Heparán Sulfato/análisis , Humanos , Glomérulos Renales/química , Glomérulos Renales/metabolismo , Persona de Mediana Edad , Valores de Referencia
13.
Biochem Soc Trans ; 28(4): 362-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10961920

RESUMEN

Growth and differentiation factor-5 (GDF-5) is a divergent member of the transforming growth factor-beta/bone morphogenetic protein (BMP) superfamily that is required for proper skeletal patterning and development in the vertebrate limb. Based on the homology of GDF-5 with other bone-inducing BMP family members, the inductive activity of a recombinant form of human GDF-5 (rhGDF-5) was evaluated in a series of in vitro assays and in vivo bone-formation models. The in vitro response to rhGDF-5 resulted in the formation of chondrogenic nodules in fetal rat calvarial cells cultured in the context of collagen or collagen/hyaluronate extracellular matrices. Matrices loaded with rhGDF-5 induced ectopic cartilaginous and osseous tissue when implanted in subcutaneous or intramuscular sites. In non-human primate long-bone-defect and spinal-fusion models, rhGDF-5 combined with a mineralized collagen matrix induced bone formation in a manner equivalent to autogenous bone. These results highlight the unique potential of rhGDF-5 in a wide variety of orthopaedic applications.


Asunto(s)
Implantes Absorbibles , Proteínas Morfogenéticas Óseas , Sustancias de Crecimiento/metabolismo , Sustancias de Crecimiento/fisiología , Proteínas Recombinantes/metabolismo , Animales , Desarrollo Óseo , Trasplante Óseo/métodos , Bovinos , Células Cultivadas , Colágeno/metabolismo , Colágeno/uso terapéutico , Femenino , Factor 5 de Diferenciación de Crecimiento , Sustancias de Crecimiento/uso terapéutico , Humanos , Masculino , Papio , Radiografía , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/uso terapéutico , Columna Vertebral/diagnóstico por imagen , Factores de Tiempo
14.
Aviat Space Environ Med ; 71(7): 699-705, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10902933

RESUMEN

BACKGROUND: With the expansion of the manned space program, an essential consideration in planning is the medical support necessary for long-term missions. Information on analogous populations serving in isolated and/or contained environments may be useful in predicting health risks for astronauts. METHODS: The present study evaluates rates of health events that occur in a highly screened, healthy military population during periods of isolation. A centralized database was designed to collect medical encounter data from U.S. Navy submarines and contains demographic information, crew rosters for each patrol, medical encounter notes, accident reports, medical evacuation reports, vital signs and laboratory data. The population included in the present analysis is composed of crewmembers aboard 136 submarine patrols between January 1, 1997 and December 31, 1998. RESULTS: A total of 2,044 initial visits to medical staff and 973 re-visits for the same condition were recorded during these patrols. Potentially mission-impacting medical events reported among crewmembers were rare (i.e., among a crew of 10 individuals, only 1-2 medical events would be expected to occur during a 100 d-mission). The most common category of medical events was injury, followed by respiratory illnesses (URIs), skin problems (minor infections, ingrown toenail), symptoms and ill-defined conditions, digestive disorders, infectious conditions, sensory organ problems (ear and eye), and musculoskeletal conditions.


Asunto(s)
Espacios Confinados , Estado de Salud , Personal Militar , Morbilidad , Vigilancia de la Población , Aislamiento Social , Medicina Submarina , Adulto , Etnicidad/psicología , Etnicidad/estadística & datos numéricos , Humanos , Masculino , Personal Militar/psicología , Personal Militar/estadística & datos numéricos , Vigilancia de la Población/métodos , Grupos Raciales , Factores de Tiempo , Estados Unidos/epidemiología
15.
Glycobiology ; 10(7): 727-35, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10910976

RESUMEN

Prompted by previous observations which suggested that the release of polymannose oligosaccharides shortly after the cotranslational N-glycosylation of proteins is a function of the ER-associated quality control system (Moore and Spiro (1994) J. Biol. Chem., 269, 12715-12721), we evaluated the effect which proteasome inhibitors have on the appearance of these free saccharide components. Employing as a model system castanospermine-treated BW5147 mouse T-lymphoma cells in which accelerated degradation of the T-cell receptor (TCR) alpha subunit takes place (Kearse et al. (1994) EMBO J., 13, 3678-3686), we noted that both lactacystin and N-acetyl-L-leucyl-L-leucyl-L-norleucinal, but not leupeptin, brought about a rapid and substantial reduction in the release of free polymannose oligosaccharides into the cytosol during pulse-chase studies, while the oligosaccharides in the intravesicular compartment remained unchanged, as measured by streptolysin O permeabilization. This inhibition was furthermore selective in that it affected solely the components terminating in a single N-acetylglucosamine residue (OS-GlcNAc(1)) and not the oligosaccharides terminating in a di-N-acetylchitobiose sequence (OS-GlcNAc(2)), which reside primarily in the intravesicular compartment. Despite the quantitative effect of the proteasome inhibitors on the cytosolic oligosaccharides, the molar distribution of the triglucosyl OS-GlcNAc(1) species was unaffected. The decrease in cytosolic oligosaccharides brought about by proteasome inhibition was reflected in a pronounced increase in the stability of the TCRalpha subunit. Our findings suggest that the N-deglycosylation and proteasome mediated degradation are coupled events. On the basis of our data and those of others we propose that the quality control mechanism involves proteasomes associated with the cytosolic side of the endoplasmic reticulum acting in concert with a membrane situated N-glycanase. Such a complex by removing the carbohydrate units could facilitate the retrograde ER to cytosol translocation of glycoproteins.


Asunto(s)
Cisteína Endopeptidasas/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Retículo Endoplásmico/metabolismo , Glicoproteínas/metabolismo , Mananos/metabolismo , Complejos Multienzimáticos/efectos de los fármacos , Oligosacáridos/metabolismo , Animales , Compartimento Celular , Citoplasma/metabolismo , Linfoma de Células T/metabolismo , Ratones , Complejo de la Endopetidasa Proteasomal , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Células Tumorales Cultivadas
16.
Glycobiology ; 10(5): 521-9, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10764841

RESUMEN

Although glucose residues in a triglucosyl sequence are essential for the N-glycosylation of proteins and in their monoglucosyl form have been implicated in lectin-like interactions with chaperones, their removal is required for the formation of mature carbohydrate units and represents the initial steps in the glycoprotein processing sequence. In order to provide a probe for the glucosylation state of newly synthesized glycoproteins obtained from normal or altered cells, we have evaluated the usefulness of recombinant endo-alpha-mannosidase employing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to monitor the change in molecular mass brought about by the release of glucosylated mannose (Glc(1-3)Man). With this approach the presence of two triglucosylated-N-linked oligosaccharides in vesicular stomatis virus (VSV) G protein formed by castanospermine-treated CHO cells or the glucosidase I deficient Lec23 mutant could be clearly demonstrated and an even more pronounced change in migration was observed upon endomannosidase treatment of their more heavily N-glycosylated lysosomal membrane glycoproteins. Furthermore, the G protein of the temperature sensitive VSV ts045 mutant was found to be sensitive to endomannosidase, resulting in a change in electrophoretic mobility consistent with the presence of mono-glucosylated-N-linked oligosaccharides. The finding that endomannosidase also acts effectively on oligosaccharide lipids, as assessed by SDS-PAGE or thin layer chromatography, indicated that it would be a valuable tool in assessing the glucosylation state of these biosynthetic intermediates in normal cells as well as in mutants or altered metabolic states, even if the polymannose portion is truncated. Endomannosidase can also be used to determine the glucosylation state of the polymannose oligosaccharides released during glycoprotein quality control and when used together with endo-beta-N- acetylglucosaminidase H can distinguish between those terminating in a single N-acetylglucosamine or in a di-N-acetylchitobiose sequence.


Asunto(s)
Glicoproteínas/química , Metabolismo de los Lípidos , Manosidasas/metabolismo , Oligosacáridos/metabolismo , Proteínas Recombinantes/metabolismo , Animales , Células CHO , Conformación de Carbohidratos , Línea Celular , Cricetinae , Electroforesis en Gel de Poliacrilamida , Proteínas de Unión al GTP/metabolismo , Humanos , Hígado/ultraestructura , Lisosomas/química , Ratas , Células Tumorales Cultivadas , Virus de la Estomatitis Vesicular Indiana/metabolismo
17.
Ultrasound Obstet Gynecol ; 16(4): 391-4, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11169319

RESUMEN

A case of fetal Pfeiffer's syndrome is presented, showing the contribution of three dimensional (3D) sonography in the diagnosis of craniosynostosis--a major feature of this syndrome.


Asunto(s)
Acrocefalosindactilia/diagnóstico por imagen , Cráneo/patología , Ultrasonografía Prenatal/métodos , Aborto Inducido , Acrocefalosindactilia/patología , Adulto , Cara/anomalías , Femenino , Humanos
18.
Histochem Cell Biol ; 114(6): 461-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11201607

RESUMEN

Asparagine-linked oligosaccharides of glycoproteins are subject to a series of trimming reactions by glucosidases and mannosidases in the endoplasmic reticulum which result in the removal of all three glucose residues and several of the nine mannose residues. At present, endomannosidase represents the only processing enzyme which cleaves internally and provides an alternate deglucosylation pathway. However, in contrast to the endoplasmic reticulum residential proteins glucosidase I and II, endomannosidase is primarily situated in the Golgi apparatus of rat liver hepatocytes and hepatocyte cell lines. We have performed a confocal immunohistochemical study to investigate endomannosidase in various rat tissues and used a monoclonal antibody against Golgi mannosidase II as a marker for the Golgi apparatus. Although immunofluorescence for both endomannosidase and Golgi mannosidase II was detectable in the epithelia of many tissues, renal proximal tubular cells, cortex and medulla of adrenal gland, gastric mucosa, and Leydig cells of testis were unreactive for endomannosidase. Furthermore, the endothelia in all studied tissues were unreactive for endomannosidase but positive for Golgi mannosidase II. It is concluded that by immunohistochemistry endomannosidase exhibits a cell type-specific expression in rat tissues.


Asunto(s)
Aparato de Golgi/enzimología , Hígado/enzimología , Manosidasas/análisis , Glándulas Suprarrenales/enzimología , Animales , Anticuerpos Monoclonales , Encéfalo/enzimología , Colon/enzimología , Endotelio/citología , Endotelio/enzimología , Células Epiteliales/enzimología , Técnica del Anticuerpo Fluorescente , Mucosa Gástrica/enzimología , Yeyuno/enzimología , Túbulos Renales Proximales/enzimología , Masculino , Manosidasas/inmunología , Páncreas/enzimología , Conejos , Ratas , Ratas Wistar , Bazo/enzimología , Glándula Tiroides/enzimología
19.
Pediatr Res ; 46(5): 510-3, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10541311

RESUMEN

We report the first case of maternal uniparental disomy for chromosome 6 (UPD6mat) ascertained through congenital adrenal hyperplasia (CAH), which arose because of reduction to homozygosity of an autosomal recessive mutation. This case suggests that UPD6mat is associated with intrauterine growth retardation (IUGR). A case of paternal UPD (involving only the short arm of chromosome 6) ascertained as CAH has previously been reported, but was not stated to have IUGR. Our patient was born with IUGR followed by extraordinarily good catch-up growth. She had a history of a marked lag in motor development. She presented at 2.65 y of age with pubarche of 3 mo duration, clitoral enlargement, and an advanced bone age. Simple virilizing CAH was diagnosed by elevations of plasma 17-hydroxyprogesterone and testosterone. Mutation analysis showed that the CAH was due to homozygosity for the 1172N exon 4 mutation. When parental DNA was examined, the mother was found to be heterozygous for the uncommon exon 4 mutation, while the father had no detectable mutations. DNA microsatellite analysis was subsequently performed on the patient and parents using polymorphic markers spanning the entire chromosome 6. Seven markers were informative for inheritance of a single maternal allele and absence of paternal alleles in the proband. Analysis of microsatellite markers from other chromosomes confirmed biparental inheritance at these loci. This combination of findings is diagnostic of UPD6mat. The only other reported case of UPD6mat was discovered serendipitously when genotyped for renal transplantation; this patient had a history of IUGR. Since both cases of UPD6mat had IUGR, the phenotype appears to include IUGR as well as the potential to unmask an autosomal recessive trait.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Aneuploidia , Cromosomas Humanos Par 6 , Retardo del Crecimiento Fetal/genética , Intercambio Materno-Fetal/fisiología , Preescolar , Análisis Mutacional de ADN , Exones , Femenino , Genes Recesivos , Homocigoto , Humanos , Linaje , Embarazo
20.
Otolaryngol Head Neck Surg ; 121(5): 539-42, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10547466

RESUMEN

Recurrent pleomorphic adenomas (RPAs) of the parotid gland are an uncommon but challenging problem. The records of 31 patients with RPAs were reviewed to assess the clinical presentation and treatment results. More than half of these patients underwent total parotidectomy. Local control was achieved in 94% of patients at 7 years (median follow-up 7.3 years). Patients who had surgery for recurrence after a formal parotidectomy were more likely to have another recurrence (63% local control at 7 years) than patients whose initial procedure was a limited excision (100% local control at 7 years; P < 0.01). Better local control was seen in 11 patients who received postoperative irradiation (100% at 10 years) than in 20 patients who did not (71% at 10 years; P < 0.28). Adequate surgical resection yields an acceptable local control rate in patients with RPAs. Postoperative radiation therapy may improve control in patients at high risk for another recurrence.


Asunto(s)
Adenoma Pleomórfico/cirugía , Recurrencia Local de Neoplasia/cirugía , Neoplasias de la Parótida/cirugía , Adenoma Pleomórfico/patología , Adenoma Pleomórfico/radioterapia , Adulto , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Glándula Parótida/patología , Glándula Parótida/cirugía , Neoplasias de la Parótida/patología , Neoplasias de la Parótida/radioterapia , Radioterapia Adyuvante , Reoperación , Resultado del Tratamiento
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