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1.
Nature ; 461(7262): 385-8, 2009 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-19759618

RESUMEN

On entering an era of global warming, the stability of the Greenland ice sheet (GIS) is an important concern, especially in the light of new evidence of rapidly changing flow and melt conditions at the GIS margins. Studying the response of the GIS to past climatic change may help to advance our understanding of GIS dynamics. The previous interpretation of evidence from stable isotopes (delta(18)O) in water from GIS ice cores was that Holocene climate variability on the GIS differed spatially and that a consistent Holocene climate optimum-the unusually warm period from about 9,000 to 6,000 years ago found in many northern-latitude palaeoclimate records-did not exist. Here we extract both the Greenland Holocene temperature history and the evolution of GIS surface elevation at four GIS locations. We achieve this by comparing delta(18)O from GIS ice cores with delta(18)O from ice cores from small marginal icecaps. Contrary to the earlier interpretation of delta(18)O evidence from ice cores, our new temperature history reveals a pronounced Holocene climatic optimum in Greenland coinciding with maximum thinning near the GIS margins. Our delta(18)O-based results are corroborated by the air content of ice cores, a proxy for surface elevation. State-of-the-art ice sheet models are generally found to be underestimating the extent and changes in GIS elevation and area; our findings may help to improve the ability of models to reproduce the GIS response to Holocene climate.


Asunto(s)
Efecto Invernadero , Cubierta de Hielo , Altitud , Groenlandia , Historia Antigua , Oxígeno/análisis , Isótopos de Oxígeno , Temperatura
2.
Acta Anaesthesiol Scand ; 59(9): 1137-44, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25939408

RESUMEN

BACKGROUND: Early postoperative mobilisation may reduce patient morbidity and improve hospital efficiency by accelerated discharge. The aim of this study was to measure postural stability early after laparoscopic surgery in order to assess how early it is safe to mobilise and discharge patients. METHODS: We included 25 women undergoing outpatient gynaecological laparoscopic surgery in the study. Patients received standardised anaesthesia with propofol, remifentanil and rocuronium. Postural stability was assessed preoperatively, at 30 min after tracheal extubation, and at discharge from the post-anaesthesia care unit using a force platform where sway area, mean sway and sway velocity were determined. The assessments were done with eyes closed and with eyes open. The primary outcome was the change in sway area with eyes closed 30 min after extubation. Data are reported as median (25-75% range). RESULTS: Three patients could not perform all the test's 30 min after extubation. Thirty minutes after extubation, sway area with eyes closed had increased significantly with 84 mm(2) (9-172, P = 0.011) and 108 mm(2) with eyes open (25-295, P = 0.0017). Median mean sway had also increased significantly 30 min postoperatively. No significant changes were found for sway velocity. We found no significant changes in mean sway, sway area or sway velocity at discharge from the post-anaesthesia care unit approximately 2 h after surgery. CONCLUSION: Postural stability was significantly impaired 30 min after outpatient gynaecological laparoscopic surgery. However, the postural stability was normalised at discharge from the post-anaesthesia care unit 2 h after surgery.


Asunto(s)
Periodo de Recuperación de la Anestesia , Ambulación Precoz/estadística & datos numéricos , Laparoscopía , Alta del Paciente/estadística & datos numéricos , Equilibrio Postural/fisiología , Adulto , Procedimientos Quirúrgicos Ambulatorios , Androstanoles , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Persona de Mediana Edad , Piperidinas , Propofol , Estudios Prospectivos , Remifentanilo , Rocuronio , Factores de Tiempo
3.
Acta Anaesthesiol Scand ; 58(2): 198-205, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24383568

RESUMEN

BACKGROUND: Pulmonary function may be impaired in connection with laparoscopic surgery, especially in the head-down body position, but the clinical importance has not been assessed in detail. The aim of this study was to assess pulmonary function after laparoscopic hysterectomy and laparoscopic cholecystectomy. We hypothesised that arterial oxygenation would be more impaired after hysterectomy performed in the head-down position than after cholecystectomy in the head-up position. METHODS: We included 60 women in this prospective, observational study. The patients underwent elective laparoscopic cholecystectomy in the 20° head-up position or hysterectomy in the 30° head-down position. The primary outcome was the difference between arterial oxygenation (PaO2 ) 2 h postoperatively and the preoperative value. Two hours and 24 h after surgery, pulmonary shunt and ventilation-perfusion mismatch were assessed by use of an automatic lung parameter estimation system. RESULTS: Two hours after surgery, the mean change from baseline in PaO2 was -0.65 kPa [95% confidence interval (CI) -3.5 to 3.4, P = 0.14] in the hysterectomy group and -0.22 kPa [95% CI -3.4 to 2.0, P = 0.12] in the cholecystectomy group (P = 0.88). Shunt was significantly greater in the cholecystectomy group 24 h after surgery compared to the hysterectomy group [4%, 95% CI 0 to 9 vs. 0%, 95% CI 0 to 7, P = 0.02]. CONCLUSIONS: Minimal impairment in pulmonary gas exchange was found after laparoscopic surgery. Pulmonary shunt was larger after laparoscopic cholecystectomy, but no clinically significant differences in postoperative pulmonary gas exchange or spirometry were found between laparoscopic hysterectomy and laparoscopic cholecystectomy.


Asunto(s)
Laparoscopía/efectos adversos , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/fisiopatología , Pulmón/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Pruebas de Función Respiratoria , Adulto , Anciano , Anestesia General , Colecistectomía Laparoscópica , Femenino , Volumen Espiratorio Forzado , Humanos , Histerectomía , Oxígeno/sangre , Dimensión del Dolor , Dolor Postoperatorio/epidemiología , Posicionamiento del Paciente , Estudios Prospectivos , Espirometría , Resultado del Tratamiento , Capacidad Vital
4.
Br J Cancer ; 108(10): 2045-55, 2013 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-23652307

RESUMEN

BACKGROUND: Autoantibodies have been detected in sera before diagnosis of cancer leading to interest in their potential as screening/early detection biomarkers. As we have found autoantibodies to MUC1 glycopeptides to be elevated in early-stage breast cancer patients, in this study we analysed these autoantibodies in large population cohorts of sera taken before cancer diagnosis. METHODS: Serum samples from women who subsequently developed breast cancer, and aged-matched controls, were identified from UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) and Guernsey serum banks to formed discovery and validation sets. These were screened on a microarray platform of 60mer MUC1 glycopeptides and recombinant MUC1 containing 16 tandem repeats. Additional case-control sets comprised of women who subsequently developed ovarian, pancreatic and lung cancer were also screened on the arrays. RESULTS: In the discovery (273 cases, 273 controls) and the two validation sets (UKCTOCS 426 cases, 426 controls; Guernsey 303 cases and 606 controls), no differences were found in autoantibody reactivity to MUC1 tandem repeat peptide or glycoforms between cases and controls. Furthermore, no differences were observed between ovarian, pancreatic and lung cancer cases and controls. CONCLUSION: This robust, validated study shows autoantibodies to MUC1 peptide or glycopeptides cannot be used for breast, ovarian, lung or pancreatic cancer screening. This has significant implications for research on the use of MUC1 in cancer detection.


Asunto(s)
Autoanticuerpos/sangre , Neoplasias de la Mama/diagnóstico , Carcinoma/diagnóstico , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Mucina-1/inmunología , Neoplasias Ováricas/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Neoplasias de la Mama/sangre , Neoplasias de la Mama/inmunología , Carcinoma/sangre , Carcinoma/inmunología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Glicopéptidos/inmunología , Humanos , Inmunoensayo , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/inmunología , Persona de Mediana Edad , Neoplasias Ováricas/sangre , Neoplasias Ováricas/inmunología , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/inmunología
5.
Br J Anaesth ; 108(2): 245-53, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22113931

RESUMEN

BACKGROUND: This study aimed at comparing total i.v. anaesthesia (TIVA) with monitored anaesthesia care (MAC) during day-surgery operative hysteroscopy regarding: operation time, time to mobilization and discharge, and patient satisfaction. METHODS: Ninety-one healthy women were randomized to MAC with paracervical local anaesthesia and remifentanil or to TIVA with propofol and remifentanil. Time from arrival to leaving the operating theatre, time from arrival in the recovery room to mobilization and discharge readiness, and patient satisfaction with MAC and TIVA were observed. RESULTS: Time from arrival to leaving the operating theatre showed no significant difference between groups (P=0.6). The time to mobilization {MAC: 53 min [inter-quartile range (IQR) 40-83], TIVA: 69 min (IQR 52-96) (P=0.017)} and the total time from arrival to discharge readiness [MAC: 118 min (IQR 95-139), TIVA: 138 (IQR 120-158) (P=0.0009)] were significantly reduced for patients in the MAC group. More patients in the MAC group 45 (91.8%) than in the TIVA group 24 (64.9%) responded positively to the question: would you like to receive the same kind of anaesthesia for a similar procedure in the future? (P=0.003). CONCLUSIONS: Paracervical local anaesthesia combined with remifentanil is suitable for operative hysteroscopy in day surgery.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Anestesia Intravenosa/métodos , Anestesia Local/métodos , Histeroscopía/métodos , Piperidinas/administración & dosificación , Adulto , Anciano , Procedimientos Quirúrgicos Ambulatorios/métodos , Periodo de Recuperación de la Anestesia , Sedación Consciente/métodos , Esquema de Medicación , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Persona de Mediana Edad , Satisfacción del Paciente , Remifentanilo
6.
J Exp Med ; 163(6): 1391-404, 1986 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-3519828

RESUMEN

A glycolipid that specifically binds shigella toxin was isolated from both HeLa cells and rabbit jejunal mucosa and identified as globotriaosylceramide (Gb3) by its identical mobility on HPTLC to authentic erythrocyte Gb3. Toxin also bound to a band tentatively identified as alpha-hydroxylated Gb3. In addition, toxin bound to P1 antigen present in group B human erythrocyte glycolipid extracts. The common feature of the three binding glycolipids is a terminal Gal alpha 1----4Gal disaccharide linked beta 1----4 to either Glc or GlcNAc. Globoisotriaosylceramide, which differs from Gb3 only in possessing a Gal alpha 1----3Gal terminal disaccharide, and LacCer, which lacks the terminal Gal residue of Gb3, were incapable of binding the toxin. Binding was shown to be mediated by the B subunit by the use of isolated toxin A and B subunits and monoclonal subunit-specific antibodies. Gb3-containing liposomes competitively inhibited the binding of toxin to HeLa cell monolayers but did not inhibit toxin-induced cytotoxicity. These studies show an identical carbohydrate-specific glycolipid receptor for shigella toxin in gut and in HeLa cells. The toxin B subunit that mediates this binding has also been shown to recognize a glycoprotein receptor with different sugar specificity. Thus, we have demonstrated that the same small (Mr 6,500) B subunit polypeptide has two distinctive carbohydrate-specific binding sites. The Gal alpha 1----4Gal disaccharide of the glycolipid toxin receptor is also recognized by the Gal-Gal pilus of uropathogenic E. coli. This suggests the possibility that the pilus and toxin B subunit contain homologous sequences. If this is true, it may be possible to use the purified Gal-Gal pilus to produce toxin-neutralizing antibodies.


Asunto(s)
Toxinas Bacterianas/metabolismo , Disentería Bacilar/etiología , Globósidos/metabolismo , Glicoesfingolípidos/metabolismo , Receptores de Superficie Celular , Trihexosilceramidas , Animales , Unión Competitiva , Cromatografía Líquida de Alta Presión , Disentería Bacilar/metabolismo , Globósidos/aislamiento & purificación , Células HeLa/análisis , Humanos , Yeyuno/análisis , Liposomas/metabolismo , Oligosacáridos/metabolismo , Conejos , Receptores Inmunológicos/metabolismo , Toxinas Shiga , Shigella dysenteriae
7.
J Exp Med ; 168(1): 343-56, 1988 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-3294333

RESUMEN

The epitope structure of the human sperm antigen reacting with antibodies present in sera of infertile women has been studied using mAb H6-3C4, which produces immobilization of human sperm in the presence of complement. Another antibody, NUH2, which also induces human sperm immobilization, was used to substantiate the presence of a receptor on sperm involved in susceptibility to immobilization. Both antibodies defined type 2 chain polylactosamine structure. H6-3C4 is directed to internally located repetitive N-acetyllactosamine, i.e., sialyl-i, i, or fucosyl-i. NUH2 defines binary alpha 2----3 sialyl type 2 chain, i.e., sialyl-I. Thus, the presence of antibodies in the sera of infertile women directed to sperm lactosaminoglycan or lactosaminolipid could be the basis for infertility in these cases.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos/inmunología , Carbohidratos/inmunología , Infertilidad Femenina/inmunología , Espermatozoides/inmunología , Amino Azúcares/inmunología , Especificidad de Anticuerpos , Secuencia de Carbohidratos , Cromatografía en Capa Delgada , Proteínas del Sistema Complemento/inmunología , Femenino , Técnica del Anticuerpo Fluorescente , Hemaglutinación , Humanos , Inmunoensayo , Masculino , Datos de Secuencia Molecular , Radioinmunoensayo , Motilidad Espermática
8.
Br J Dermatol ; 163(5): 1007-13, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20731651

RESUMEN

BACKGROUND: Hirsutism is a common disorder in women of reproductive age, and androgen disturbances may aggravate the condition. Limited evidence exists regarding efficacy of hair removal in this specific population and no data are available for patients with verified normal testosterone levels. OBJECTIVES: To compare efficacy and safety of intense pulsed light (IPL) vs. long-pulsed diode laser (LPDL) in a well-defined group of hirsute women with normal testosterone levels. METHODS: Thirty-one hirsute women received six allocated split-face treatments with IPL (525-1200 nm; Palomar Starlux IPL system) and LPDL (810 nm; Asclepion MeDioStar XT diode laser). Testosterone levels were measured three times during the study period. Patients with intrinsically normal or medically normalized testosterone levels throughout the study were included in efficacy assessments (n = 23). Endpoints were reduction in hair counts assessed by blinded photoevaluations at baseline and 1, 3 and 6 months after final treatment, patient-evaluated reduction in hairiness, patient satisfaction, treatment-related pain and adverse effects. RESULTS: IPL and LPDL reduced hair counts significantly, with median reductions from baseline of 77%, 53% and 40% for IPL and 68%, 60% and 34% for LDPL at 1, 3 and 6 months, respectively. At 6 months follow-up, there was no significant difference between treatments in terms of hair reduction (P = 0·427), patient assessment of hairiness (P = 0·250) and patient satisfaction (P = 0·125). Pain scores were consistently higher for IPL [median 6, interquartile range (IQR) 4-7] than LPDL (median 3, IQR 2-5) (P < 0·001). CONCLUSION: Hirsute women with normal or medically normalized testosterone levels responded equally well to IPL and LPDL treatments of facial hairiness, but the efficacy declined over 6 months.


Asunto(s)
Remoción del Cabello/métodos , Hirsutismo/radioterapia , Terapia por Láser/métodos , Láseres de Semiconductores/uso terapéutico , Adulto , Femenino , Hirsutismo/sangre , Humanos , Terapia por Láser/efectos adversos , Dimensión del Dolor , Satisfacción del Paciente , Testosterona/sangre
9.
Nature ; 431(7005): 147-51, 2004 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-15356621

RESUMEN

Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.

10.
Br J Cancer ; 100(11): 1746-54, 2009 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-19436292

RESUMEN

Changes in the composition of glycans added to glycoproteins and glycolipids are characteristic of the change to malignancy. Sialyl-Tn (STn) is expressed by 25-30% of breast carcinomas but its expression on normal tissue is highly restricted. Sialyl-Tn is an O-linked disaccharide that can be carried on various glycoproteins. One such glycoprotein MUC1 is expressed by the vast majority of breast carcinomas. Both STn and MUC1 have been considered as targets for immunotherapy of breast cancer patients. Here we used different immunogens to target STn in an MUC1 transgenic mouse model of tumour challenge. We show that synthetic STn coupled to keyhole limpet haemocyanin (Theratope), induced antibodies to STn that recognised the glycan carried on a number of glycoproteins and in these mice a significant delay in tumour growth was observed. The protection was dependent on STn being expressed by the tumour and was antibody mediated. Affinity chromatography of the STn-expressing tumour cell line, followed by mass spectrometry, identified osteopontin as a novel STn-carrying glycoprotein which was highly expressed by the tumours. These results suggest that if antibodies can be induced to a number of targets expressed by the tumour cells, a humoral response can be effective in controlling tumour growth.


Asunto(s)
Anticuerpos/inmunología , Antígenos de Carbohidratos Asociados a Tumores/inmunología , Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/metabolismo , Neoplasias/inmunología , Vacunas/inmunología , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Hemocianinas/inmunología , Inmunoterapia , Ratones , Ratones Endogámicos BALB C , Mucina-1/inmunología , Neoplasias/metabolismo , Neoplasias/patología , Tasa de Supervivencia
11.
J Cell Biol ; 134(6): 1411-25, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8830771

RESUMEN

COP I-coated vesicles were analyzed for their content of resident Golgi enzymes (N-acetylgalactosaminyltransferase; N-acetylglucosaminyltransferase I; mannosidase II; galactosyltransferase), cargo (rat serum albumin; polyimmunoglobulin receptor), and recycling proteins (-KDEL receptor; ERGIC-53/p58) using biochemical and morphological techniques. The levels of these proteins were similar when the vesicles were prepared under interphase or mitotic conditions showing that sorting was unaffected. The average density relative to starting membranes for resident enzymes (14-30%), cargo (16-23%), and recycling proteins (81-125%) provides clues to the function of COP I vesicles in transport through the Golgi apparatus.


Asunto(s)
Proteínas Bacterianas/metabolismo , Interfase/fisiología , Membranas Intracelulares/química , Mitosis/fisiología , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/análisis , Transporte Biológico/fisiología , Compartimento Celular/fisiología , Aparato de Golgi/química , Aparato de Golgi/enzimología , Inmunohistoquímica , Membranas Intracelulares/enzimología , Hígado/citología , Manosidasas/análisis , Microscopía Inmunoelectrónica , Datos de Secuencia Molecular , Proteínas/metabolismo , Ratas
12.
Science ; 218(4579): 1273-7, 1982 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-17770148

RESUMEN

The polar ice sheets are rich sources of information on past atmospheric conditions, including paleoclimates. A new deep ice core has been drilled in south Greenland. Comparison of the oxygen isotopic profile with that from camp Century and with a deep-sea foraminifera record indicates that the new core reaches back to about 90,000 years before present in a continuous sequence. The details in the Wisconsin part of the ice core records seem to be climatically, significant, and the general trends reveal all of the relevant Emiliani stages recorded in deep-sea cores. The redated Camp Century record suggests a dramatic termination of the Eem/Sangamon interglacial.

13.
J Am Chem Soc ; 130(25): 7988-96, 2008 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-18512920

RESUMEN

The charge density (CD) of coordination polymer Co3(C8H4O4)4(C4H12N)2(C5H11NO)3 (1) has been determined from multipole modeling of structure factors obtained from single-crystal synchrotron X-ray diffraction measurements at 16 K. The crystal structure formally contains a negatively charged framework with cations and neutral molecules in the voids. However, the CD suggests that the framework is close to neutral, and therefore qualitative conclusions based on formal charge counting, e.g., about guest inclusion properties, will be incorrect. There are considerable differences in the charge distributions of the three unique benzenedicarboxylic acid linkers, which are widely used in coordination polymers. This suggests that the electrostatic properties of coordination polymer cavities, and thereby their inclusion properties, are highly tunable. The electron density topology shows that the tetrahedrally coordinated Co atom has an atomic volume which is 15% larger than that of the octahedrally coordinated Co atom. The crystal structure has both ferromagnetic and antiferromagnetic interactions, but no direct metal-metal bonding is evidenced in the CD. The magnetic ordering therefore takes place through superexchange in the oxygen bridges and the aromatic linkers. Bonding analysis of the experimental CD reveals that two oxygen atoms, O(1) and O(11), have significant covalent contributions to the metal-ligand bonding, whereas all other oxygen atoms have closed-shell interactions with the metals. This indicates that these two oxygen atoms are the key mediators of the magnetic ordering.

14.
Ann Rheum Dis ; 67(10): 1480-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17998215

RESUMEN

OBJECTIVES: MUC5B contains sulfated and sialylated oligosaccharides that sequester water required for moisturising the oral mucosa. Xerostomia, in patients with Sjögren syndrome, is generally associated with reduced quantities, rather than altered properties, of saliva. Here, we determined the amount of MUC5B (mRNA and protein) as well as sulfation levels in salivary glands of patients with normal or altered unstimulated salivary flow. Localisation of MUC5B and sulfated MUC5B, as well as total levels sulfated groups were determined and compared with acini basal lamina disorganisation. PATIENTS AND METHODS: In all, 18 patients with normal or altered unstimulated salivary flow and 16 controls were studied. MUC5B mRNA and protein were evaluated in salivary glands by semiquantitative RT-PCR and Western blot analysis. MUC5B sulfation was determined by Western blotting. MUC5B and sulfo-Lewis(a) antigen localisation were assessed by immunohistochemistry. The total amount of sulfated oligosaccharides was determined microdensitometrically. RESULTS: No significant differences were detected in MUC5B mRNA and protein levels between controls and patients, while sulfo-Lewis(a) antigen levels were lower in patients. The number of sulfo-Lewis(a) positive mucous acini was reduced in patients but no correlation was observed between lower levels of sulfation and unstimulated salivary flow. Microdensitometric data confirmed the presence of reduced sulfated oligosaccharides levels in mucous acini from patients with highly disorganised basal lamina. CONCLUSION: Disorganisation of the basal lamina observed in patients with Sjögren syndrome may lead to dedifferentiation of acinar mucous cells and, as a consequence, alter sulfation of MUC5B. These changes are suggested to represent a novel mechanism that may explain xerostomia in these patients.


Asunto(s)
Mucinas/metabolismo , Síndrome de Sjögren/metabolismo , Xerostomía/metabolismo , Adulto , Densitometría , Femenino , Expresión Génica , Humanos , Antígenos del Grupo Sanguíneo de Lewis , Persona de Mediana Edad , Mucina 5B , Mucinas/genética , Oligosacáridos/metabolismo , ARN Mensajero/genética , Glándulas Salivales/metabolismo , Salivación , Sulfatos/metabolismo
15.
J Clin Invest ; 90(3): 965-72, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1522244

RESUMEN

Women with a history of recurrent Escherichia coli urinary tract infections (UTIs) are two to three times more likely to be nonsecretors of histo-blood group antigens than are women without such a history. Further, uroepithelial cells from women who are nonsecretors show enhanced adherence of uropathogenic E. coli compared with cells from secretors. To investigate the hypothesis that nonsecretors express unique receptors for uropathogenic E. coli related to their genetic background, we extracted glycosphingolipids (GSLs) from vaginal epithelial cells collected from nonsecretors and secretors and used an assay in which radiolabeled uropathogenic E. coli were bound to these GSLs separated on TLC plates. An E. coli strain (R45) expressing both P and F adhesins, which was isolated from one of these patients' UTIs, was metabolically labeled with 35S for the TLC binding assay. The radiolabeled E. coli R45 bound to two extended globo-series GSLs, sialosyl gal-globoside (SGG) and disialosyl gal-globoside (DSGG), found in the GSL extracts from nonsecretors but not from secretors. The identity of SGG in the nonsecretor GSL extracts was confirmed in radioimmunoassays using an mAb to SGG and in immunofluorescence assays with this mAb and native vaginal epithelial cells. We show that SGG and DSGG are selectively expressed by epithelial cells of nonsecretors, presumably as a result of sialylation of the gal-globoside precursor glycolipid, which in secretors is fucosylated and processed to ABH antigens. The presence of SGG and DSGG may account for the increased binding of E. coli to uroepithelial cells from nonsecretors and for their increased susceptibility to recurrent UTI.


Asunto(s)
Adhesión Bacteriana , Antígenos de Grupos Sanguíneos , Infecciones por Escherichia coli/microbiología , Glicoesfingolípidos/metabolismo , Infecciones Urinarias/microbiología , Vagina/microbiología , Adulto , Secuencia de Carbohidratos , Epitelio/microbiología , Escherichia coli/fisiología , Infecciones por Escherichia coli/sangre , Femenino , Técnica del Anticuerpo Fluorescente , Glicoesfingolípidos/análisis , Humanos , Datos de Secuencia Molecular , Recurrencia , Infecciones Urinarias/sangre , Vagina/química
16.
APMIS ; 115(1): 22-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17223848

RESUMEN

The study aimed to demonstrate the expression of nitric oxide converting enzyme, nitric oxide synthase (e-NOS), and endothelin-1 (Et-1) in formalin-fixed paraffin-embedded placental tissue, and to demonstrate a difference in staining intensity between heavy smokers and non-smokers. Term placentas from pregnancies from otherwise healthy women smoking 15 or more cigarettes per day (heavy smokers) and term placentas from a matching group of non-smokers were included. The antibodies for Et-1 and e-NOS are recommended for cryostat sections. We evaluated the antibodies on paraffin-embedded tissue combined with the streptavidin-biotin-peroxidase technique. Et-1 and e-NOS were demonstrated in the placental vasculature, the trophoblast, and the amnion. A blinded comparative study showed no reproducible significant differences in the staining intensity of the antigen-antibody reaction to Et-1 and e-NOS between the two groups.


Asunto(s)
Endotelina-1/metabolismo , Óxido Nítrico Sintasa/metabolismo , Placenta/metabolismo , Complicaciones del Embarazo/patología , Fumar/metabolismo , Adulto , Endotelio Vascular/enzimología , Femenino , Humanos , Inmunohistoquímica , Placenta/irrigación sanguínea , Embarazo , Fumar/efectos adversos , Fumar/patología
17.
Virchows Arch ; 451(4): 805-14, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17694322

RESUMEN

Testicular germ cell tumours (TGCT) exhibit remarkable ability to differentiate into virtually all somatic tissue types. In this study, we investigated changes in mucin-type O-glycosylation, which have been associated with somatic cell differentiation and cancer. Expression profile of simple mucin-type O-glycans (Tn, sialyl-Tn, T), histo-blood group H and A variants and six polypeptide GalNAc-transferases (T1-4, T6, T11) that control the site and density of O-glycosylation were analysed by immunohistochemistry during human testis development and in TGCT. Normal testis showed a restricted pattern; gonocytes expressed abundant sialyl-Tn and sialyl-T, and adult spermatogonia were devoid of any glycans, whereas spermatocytes and spermatids expressed exclusively glycans Tn and T and the GalNAc-T3 isoform. A subset of mature ejaculated spermatozoa expressed an additional glycan sialyl-T. The pattern found in testicular neoplasms recapitulated the developmental order: Pre-invasive carcinoma in situ (CIS) cells and seminoma expressed fetal type sialylated glycans in keeping with their gonocyte-like phenotype. Neither simple mucin-type O-glycans nor GalNAc-transferase isoforms were found in undifferentiated nonseminoma, i.e. embryonal carcinoma, whereas teratomas expressed them all to some extent but in a disorganized manner. We concluded that simple mucin-type O-glycans and their transferases are developmentally regulated in the human testis, with profound changes associated with neoplasia. The restricted O-glycosylation pattern in haploid germ cells suggests a role in their maturation or egg recognition/fertilization warranting further studies in male infertility, whereas the findings in TGCT provide new diagnostic tools and support our hypothesis that testicular cancer is a developmental disease of germ cell differentiation.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Antígenos Virales de Tumores/metabolismo , Transformación Celular Neoplásica/metabolismo , N-Acetilgalactosaminiltransferasas/metabolismo , Neoplasias Testiculares/metabolismo , Testículo/metabolismo , Antígenos de Carbohidratos Asociados a Tumores/genética , Antígenos Virales de Tumores/genética , Diferenciación Celular/fisiología , Transformación Celular Neoplásica/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , N-Acetilgalactosaminiltransferasas/genética , Fenotipo , Espermatogénesis/fisiología , Espermatozoides/patología , Neoplasias Testiculares/patología , Testículo/patología , Polipéptido N-Acetilgalactosaminiltransferasa
18.
J Natl Cancer Inst ; 81(15): 1151-7, 1989 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-2664192

RESUMEN

Expression of histo-blood group ABH antigens in 53 cases of ovarian cancer was examined by immunoperoxidase staining of Formalin-fixed as well as frozen histological sections with various monoclonal antibodies, including those defining type 1, 2, 3, and 4 chain A. Findings of major interest were (a) deletion of A and B determinants in tumors from histo-blood group A and B individuals, and a high incidence of H antigen deletion in tumors from group O individuals were observed and (b) strong expression of incompatible A antigen in two of 10 samples from group B patients and in two of nine samples from group O patients was demonstrated. A antigen expression was defined by monoclonal antibody AH21, which reacts with monofucosyl type 1 chain A (ALed), but not by other types of anti-A antibodies directed to difucosyl type 1 chain A (ALeb), mono- or difucosyl type 2 chain A, or type 3 or type 4 chain A. The reactivity of monoclonal antibody AH21 was abolished by alpha-N-acetylgalactosaminidase from chicken liver. These findings clearly identified the specific expression of incompatible A antigen with the structure monofucosyl type 1 chain A (ALed) in tumors from histo-blood group B and O individuals.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Isoantígenos/análisis , Neoplasias Ováricas/inmunología , Femenino , Humanos , Técnicas para Inmunoenzimas
19.
Cancer Res ; 48(1): 181-7, 1988 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-2446741

RESUMEN

The blood group A determinant is carried by four basic carrier carbohydrate chains. This paper reports the expression of blood group A variants, as determined by immunohistology with highly specific monoclonal anti-A antibodies, in 18 adenocarcinomas of the distal colon, 4 specimens of normal proximal mucosa from group A persons, and 5 specimens of fetal colonic mucosa. Monoclonal antibodies directed to type 1 chain A, type 1 chain ALeb, type 2 chain A, type 2 chain ALey, and type 3 chain A (repetitive A) were used. In normal mucosa, type 1 chain A and ALeb were expressed in proximal regions. Type 1 chain A was expressed in columnar cells, whereas type 1 chain ALeb was found in goblet cells. Type 2 and type 3 chain A structures were not found in normal adult mucosa. All types of A antigens were detected in adenocarcinomas from the distal colon as well as in normal fetal mucosa. In fetal mucosa, type 1 chain A and ALeb antigens and type 3 chain A antigens were expressed in columnar cells, whereas type 2 chain A and Ley and type 1 chain ALeb antigens were found in goblet cells. The results indicate that blood group A antigens with type 1, 2, and 3 carriers are present in fetal mucosa and adenocarcinomas of distal colon, while epithelial mucosa of normal adult colon is characterized by the exclusive expression of type 1 chain A antigens.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Colon/inmunología , Neoplasias del Colon/sangre , Anciano , Carbohidratos/análisis , Epítopos/análisis , Femenino , Feto/inmunología , Humanos , Masculino , Persona de Mediana Edad
20.
Cancer Res ; 48(8): 2214-20, 1988 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-2450649

RESUMEN

Two monoclonal antibodies, TKH1 and TKH2, directed toward the sialosyl-Tn structure (NeuAc alpha 2----6GalNAc alpha 1----O-Ser or Thr), which display a remarkable immunohistological tumor specificity, were generated by immunization with ovine submaxillary mucin. The reactivity of these antibodies was monitored by solid phase enzyme-linked immunosorbent assay with different native and glycosidase-treated mucins and glycoproteins. Binding of the antibody to ovine submaxillary mucin glycoprotein was strongly inhibited by the O-linked disaccharide NeuAc alpha 2----6GalNAc alpha 1----O-serine, less strongly by NeuAc alpha 2----6GalNAc beta 1----O-propyl, and weakly by the monosaccharide GalNac. The reactivity was compared with previously established anti-Tn antibodies B72.3, NCC-Lu-35, and NCC-Lu-81. The antibody B72.3 was prepared previously after immunization with metastatic breast adenocarcinoma and its epitope was claimed to be GalNAc alpha 1----O-Ser (or - Thr) by Springer and associates [Springer, G.F., et al. In: T. Dao, et al. (eds.), Tumor Markers and Their Significance in the Management of Breast Cancer, pp. 47-70. New York: A.R. Liss, 1986]. The antibody was found to show very similar reactivity as that of TKH1/TKH2, and its reactivity to ovine submaxillary mucin was inhibited specifically by NeuAc alpha 2----6GalNAc alpha 1----O-serine, indicating that the antibody is clearly directed to sialosyl-Tn antigen. Immunohistological study of the distribution of this antigen in various normal human tissues and carcinomas by TKH1/TKH2 antibodies, as well as B72.3 and monoclonal antibodies NCC-Lu-35/81, which are directed to GalNAc alpha 1----O-Ser or Thr (Tn), was performed. The sialosyl-Tn antigen was not found in normal tissue except for a weak expression in Leydig cells of the testis, goblet cells of the colon, and parietal cells of the stomach. In contrast, the sialosyl-Tn antigen was strongly expressed in a large number of adenocarcinomas. As expected from the specificity studies, B72.3 shows the same reactivity as TKH1 and TKH2. Thus, both sialosyl-Tn (NeuAc alpha 2----6GalNAc alpha 1----O-Ser/Thr) and Tn (GalNAc alpha 1----O-Ser/Thr) are good tumor markers, and combined use of antibodies directed to these structures might be useful in the screening and classification of cancer.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Neoplasias/inmunología , Antígenos de Carbohidratos Asociados a Tumores , Biomarcadores de Tumor/inmunología , Epítopos/análisis , Animales , Anticuerpos Monoclonales/biosíntesis , Especificidad de Anticuerpos , Disacáridos/farmacología , Ratones , Ratones Endogámicos BALB C , Monosacáridos/farmacología
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