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1.
Arthritis Res Ther ; 22(1): 97, 2020 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-32349791

RESUMEN

OBJECTIVES: To systematically review the impact of tapering targeted therapies (bDMARDs or JAKis) on the risk of serious infections and severe adverse events (SAEs) in patients with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA) in remission or low disease activity (LDA) state. MATERIALS AND METHODS: A meta-analysis based on a systematic review of PubMed, Embase, Cochrane, until August 2019, as well as relevant databases of international conferences, was used to evaluate the risk difference (RD) at 95% confidence interval (95% CI) of incidence density of serious infections, SAEs, malignancies, cardiovascular adverse events (CV AEs), or deaths after tapering (dose reduction or spacing) compared to continuation of targeted therapies. RESULTS: Of the 1957 studies initially identified, 13 controlled trials (9 RA and 4 SpA trials) were included in the meta-analysis. 1174 patient-years were studied in the tapering group (TG) versus 1086 in the usual care group (UC). There were 1.7/100 patient-year (p-y) serious infections in TG versus 2.6/100 p-y in UC (RD (95% CI) 0.01 (0.00 to 0.02), p = 0.13) and 7.4/100 p-y SAEs in TG versus 6.7/100 p-y in UC (RD 0.00 (- 0.02 to 0.02), p = 0.82). The risk of malignancies, CV AEs, or deaths did not differ between the tapering and the usual care groups. Subgroup analysis (RA and SpA) detected no significant differences between the two groups. CONCLUSION: We could not show significant impact of tapering bDMARD or JAKi over continuation concerning the risk of serious infections, SAEs, malignancies, CV AEs, or deaths in RA and SpA patients in remission or LDA state.


Asunto(s)
Antirreumáticos/administración & dosificación , Artritis Reumatoide , Productos Biológicos/administración & dosificación , Quinasas Janus/antagonistas & inhibidores , Espondiloartritis , Inhibidores del Factor de Necrosis Tumoral/administración & dosificación , Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Ensayos Clínicos Controlados como Asunto , Humanos , Espondiloartritis/tratamiento farmacológico
2.
Sci Rep ; 7: 39997, 2017 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-28054672

RESUMEN

We report the quantum efficiency of photoluminescence processes of Er optical centers as well as the thermal quenching mechanism in GaN epilayers prepared by metal-organic chemical vapor deposition. High resolution infrared spectroscopy and temperature dependence measurements of photoluminescence intensity from Er ions in GaN under resonant excitation excitations were performed. Data provide a picture of the thermal quenching processes and activation energy levels. By comparing the photoluminescence from Er ions in the epilayer with a reference sample of Er-doped SiO2, we find that the fraction of Er ions that emits photon at 1.54 µm upon a resonant optical excitation is approximately 68%. This result presents a significant step in the realization of GaN:Er epilayers as an optical gain medium at 1.54 µm.

3.
Ann Rheum Dis ; 76(1): 29-42, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27457514

RESUMEN

BACKGROUND: New drugs and new evidence concerning the use of established treatments have become available since the publication of the first European League Against Rheumatism (EULAR) recommendations for the management of gout, in 2006. This situation has prompted a systematic review and update of the 2006 recommendations. METHODS: The EULAR task force consisted of 15 rheumatologists, 1 radiologist, 2 general practitioners, 1 research fellow, 2 patients and 3 experts in epidemiology/methodology from 12 European countries. A systematic review of the literature concerning all aspects of gout treatments was performed. Subsequently, recommendations were formulated by use of a Delphi consensus approach. RESULTS: Three overarching principles and 11 key recommendations were generated. For the treatment of flare, colchicine, non-steroidal anti-inflammatory drugs (NSAIDs), oral or intra-articular steroids or a combination are recommended. In patients with frequent flare and contraindications to colchicine, NSAIDs and corticosteroids, an interleukin-1 blocker should be considered. In addition to education and a non-pharmacological management approach, urate-lowering therapy (ULT) should be considered from the first presentation of the disease, and serum uric acid (SUA) levels should be maintained at<6 mg/dL (360 µmol/L) and <5 mg/dL (300 µmol/L) in those with severe gout. Allopurinol is recommended as first-line ULT and its dosage should be adjusted according to renal function. If the SUA target cannot be achieved with allopurinol, then febuxostat, a uricosuric or combining a xanthine oxidase inhibitor with a uricosuric should be considered. For patients with refractory gout, pegloticase is recommended. CONCLUSIONS: These recommendations aim to inform physicians and patients about the non-pharmacological and pharmacological treatments for gout and to provide the best strategies to achieve the predefined urate target to cure the disease.


Asunto(s)
Supresores de la Gota/uso terapéutico , Gota/tratamiento farmacológico , Corticoesteroides/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Técnica Delphi , Consejo Dirigido , Medicina Basada en la Evidencia , Gota/sangre , Gota/terapia , Humanos , Interleucina-1/antagonistas & inhibidores , Estilo de Vida , Educación del Paciente como Asunto , Brote de los Síntomas , Ácido Úrico/sangre
4.
Lupus ; 23(1): 69-74, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24213308

RESUMEN

Objective To evaluate the extended follow-up of the CYCLOFA-LUNE trial, a randomized prospective trial comparing two sequential induction and maintenance treatment regimens for proliferative lupus nephritis based either on cyclophosphamide (CPH) or cyclosporine A (CyA). Patients and methods Data for kidney function and adverse events were collected by a cross-sectional survey for 38 of 40 patients initially randomized in the CYCLOFA-LUNE trial. Results The median follow-up time was 7.7 years (range 5.0-10.3). Rates of renal impairment and end-stage renal disease, adverse events (death, cardiovascular event, tumor, premature menopause) did not differ between the CPH and CyA group, nor did mean serum creatinine, 24 h proteinuria and SLICC damage score at last follow-up. Most patients in both groups were still treated with glucocorticoids, other immunosuppressant agents and blood pressure lowering drugs. Conclusion An immunosuppressive regimen based on CyA achieved similar clinical results to that based on CPH in the very long term.


Asunto(s)
Ciclofosfamida/efectos adversos , Ciclosporina/efectos adversos , Inmunosupresores/efectos adversos , Nefritis Lúpica/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Proliferación Celular/efectos de los fármacos , Estudios de Seguimiento , Humanos , Nefritis Lúpica/patología , Insuficiencia Renal/inducido químicamente , Insuficiencia Renal/patología
5.
Prague Med Rep ; 112(4): 298-304, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22142525

RESUMEN

Although very rare in a European context, a bite from the black mamba Dendroaspis polylepis is an event that poses an immediate threat to life. Given the content of neurotoxins in the snake's venom, the mortality of envenomation reaches 100% in almost every case if ventilation is not provided in a timely manner and adequate therapy initiated. The report describes a case of a snake breeder being envenomed. This 31-year-old man was bitten by a black mamba on his finger, and who subsequently developed clinical symptoms of envenoming typical for the species. Thanks to mechanical ventilation being employed promptly, with myorelaxation during generalized muscle fasciculations, and particularly owing to the eventual antivenin therapy, the patient's condition settled without consequences. In addition to describing the given case in detail, the paper discusses the composition and mechanisms of action of black mamba venom, while providing guidelines for adequate therapy.


Asunto(s)
Elapidae , Mordeduras de Serpientes , Adulto , Animales , Antivenenos/uso terapéutico , Venenos Elapídicos , Humanos , Masculino , Mordeduras de Serpientes/diagnóstico , Mordeduras de Serpientes/fisiopatología , Mordeduras de Serpientes/terapia
6.
Urol Int ; 87(1): 120-4, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21734351
7.
Br J Cancer ; 103(7): 1057-65, 2010 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-20736942

RESUMEN

BACKGROUND: Tumour necrosis reflects the presence of hypoxia, which can be indicative of an aggressive tumour phenotype. The aim of this study was to investigate whether histological necrosis is a useful predictor of outcome in patients with pancreatic ductal carcinoma (PDC). METHODS: We reviewed histopathological findings in 348 cases of PDC in comparison with clinicopathological information. We counted small necrotic foci (micronecrosis) as necrosis, in addition to massive necrosis that had been only defined as necrosis in previous studies. The reproducibility of identifying histological parameters was tested by asking five independent observers to blindly review 51 examples of PDC. RESULTS: Both micronecrosis and massive necrosis corresponded to hypoxic foci expressing carbonic anhydrase IX detected by immunohistochemistry. Multivariate survival analysis showed that histological necrosis was an independent predictor of poor outcome in terms of both disease-free survival (DFS) and disease-specific survival (DSS) of PDC patients. In addition, metastatic status, and lymphatic, venous, and intrapancreatic neural invasion were independent prognostic factors for shorter DFS and metastatic status, margin status, lymphatic invasion, and intrapancreatic neural invasion were independent prognostic factors for DSS. The interobserver reproducibility of necrosis identification among the five independent observers was 'almost perfect' (κ-value of 0.87). CONCLUSION: Histological necrosis is a simple, accurate, and reproducible predictor of postoperative outcome in PDC patients.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Anhidrasas Carbónicas/metabolismo , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/patología , Anhidrasa Carbónica IX , Carcinoma Ductal Pancreático/mortalidad , Hipoxia de la Célula , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/cirugía , Periodo Posoperatorio , Pronóstico , Reproducibilidad de los Resultados
8.
Lupus ; 19(11): 1281-9, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20605876

RESUMEN

Intravenous cyclophosphamide is considered to be the standard of care for the treatment of proliferative lupus nephritis. However, its use is limited by potentially severe toxic effects. Cyclosporine A has been suggested to be an efficient and safe treatment alternative to cyclophosphamide. Forty patients with clinically active proliferative lupus nephritis were randomly assigned to one of two sequential induction and maintenance treatment regimens based either on cyclophosphamide or Cyclosporine A. The primary outcomes were remission (defined as normal urinary sediment, proteinuria <0.3 g/24 h, and stable s-creatinine) and response to therapy (defined as stable s-creatinine, 50% reduction in proteinuria, and either normalization of urinary sediment or significant improvement in C3) at the end of induction and maintenance phase. Secondary outcomes were incidence of adverse events, and relapse-free survival. At the end of the induction phase, 24% of the 21 patients treated by cyclophosphamide achieved remission, and 52% achieved response, as compared with 26% and 43%, respectively of the 19 patients treated by the Cyclosporine A. At the end of the maintenance phase, 14% of patients in cyclophosphamide group, and 37% in Cyclosporine A group had remission, and 38% and 58% respectively response. Treatment with Cyclosporine A was associated with transient increase in blood pressure and reversible decrease in glomerular filtration rate. There was no significant difference in median relapse-free survival. In conclusion, Cyclosporine A was as effective as cyclophosphamide in the trial of sequential induction and maintenance treatment in patients with proliferative lupus nephritis and preserved renal function.(ClinicalTrials.gov identifier: NCT00976300)


Asunto(s)
Ciclofosfamida , Ciclosporina/uso terapéutico , Inmunosupresores , Nefritis Lúpica/tratamiento farmacológico , Adulto , Ciclofosfamida/administración & dosificación , Ciclofosfamida/uso terapéutico , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Infusiones Intravenosas , Pruebas de Función Renal , Nefritis Lúpica/diagnóstico , Masculino , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
9.
Neoplasma ; 56(4): 298-302, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19473055

RESUMEN

We investigated the expression of cell-associated CAIX protein in histological sections of the transitional cell carcinoma (TCC) of the urinary tract and of the soluble form of CAIX (s-CAIX) shed by the tumor into the serum and urine of TCC patients. A total of 23 patients with histologically confirmed TCC or squamous cell carcinoma (SCC) were enrolled in the pilot study. Sixteen healthy individuals served as controls. Membrane-bound CAIX was present in the tumor cells near the endoluminal surface. Necrosis was observed in only 4 samples. Using Western blots, s-CAIX concentrated from urine was visualized as a double band at 50 and 54 kDa. In most cases, the presence of s-CAIX in the urine correlated with CAIX expression in the tumor. On the other hand, s-CAIX did not exceed the normal level in the serum of TCC patients. Urine from patients with TCC of the urinary bladder and renal pelvis contained s-CAIX, allowing the detection of tumors in approximately 70% of the patients. Moreover, two additional patients with suspected, but unconfirmed bladder tumor, with s-CAIX detected in urine, developed tumors identified as TCC within six months. We suggest that after a simple, rapid and sensitive test, monitoring s-CAIX levels in urine will be developed, it may be useful for early detection of relapse in patients following transurethral tumor resection.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Anhidrasas Carbónicas/metabolismo , Carcinoma de Células Transicionales/enzimología , Pelvis Renal/enzimología , Vejiga Urinaria/enzimología , Neoplasias Urológicas/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Anhidrasa Carbónica IX , Carcinoma de Células Transicionales/sangre , Carcinoma de Células Transicionales/orina , Estudios de Casos y Controles , Membrana Celular/enzimología , Membrana Celular/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Técnicas para Inmunoenzimas , Pelvis Renal/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proyectos Piloto , Pronóstico , Vejiga Urinaria/patología , Neoplasias Urológicas/sangre , Neoplasias Urológicas/orina , Adulto Joven
10.
Rozhl Chir ; 88(2): 62-4, 2009 Feb.
Artículo en Checo | MEDLINE | ID: mdl-19413261

RESUMEN

Authors present a case report of the young man, Afghan military policeman, who was with gunshot injury referred to treatment to the Czech field hospital stationed in Kabul international airport at the time of the 4th contingent of the field hospital and chemical unit in international operation ISAF Afghanistan. The patient suffered from a double gunshot of the chest wall that caused open compound fracture of the left collar bone, fracture of the sternal bone and the right scapula and hemorhagic contusion of the left apical lung although it was not a penetrating injury of the chest. Left side posterolateral thoracotomy was performed and non-anatomical resection of the apical lung and further drainage of the pleural cavity were done. Revision of both the gunshot canals with debridements was further performed, of course. Postoperative course was without any complications and patient was sent to local Afghan hospital on the sixth postoperative day.


Asunto(s)
Traumatismos Torácicos/cirugía , Heridas por Arma de Fuego/cirugía , Adulto , Campaña Afgana 2001- , Humanos , Masculino , Personal Militar , Traumatismos Torácicos/patología , Heridas por Arma de Fuego/patología , Adulto Joven
11.
Phys Rev Lett ; 101(14): 147206, 2008 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-18851569

RESUMEN

The role of graphene in mediating the exchange interaction is theoretically investigated when placed between two ferromagnetic dielectric materials. The calculation based on a tight-binding model illustrates that the magnetic interactions at the interfaces affect not only the graphene band structure but also the thermodynamic potential of the system, leading to an effective exchange bias between magnetic layers. The analysis indicates a strong dependence of the exchange bias on the properties of the mediating layer, revealing an efficient mechanism of electrical control even at room temperature.

12.
Folia Biol (Praha) ; 54(3): 73-80, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18647546

RESUMEN

Nephrologists deal with a host of pathologic conditions involving renal and systemic endothelium. Both in native and transplanted kidneys, often the insult to the renal endothelium initiates the pathogenic process ultimately leading to the loss of organ function. Also, systemic atherosclerosis is accelerated in patients with renal dysfunction. In this review we would like to cover the possible role of CECs and their counterparts--circulating EPCs in the pathogenesis of endothelial dysfunction associated with chronic renal failure, ANCA-associated vasculitis, and progression of chronic renal disease.


Asunto(s)
Células Endoteliales/fisiología , Fallo Renal Crónico/patología , Células Madre/fisiología , Anticuerpos Anticitoplasma de Neutrófilos/sangre , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Biomarcadores , Recuento de Células , Humanos , Trasplante de Riñón/patología , Vasculitis/etiología , Vasculitis/patología
14.
Br J Cancer ; 89(6): 1067-71, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-12966427

RESUMEN

Tumour-associated protein carbonic anhydrase IX (CA IX) has two major forms. One is a cell-associated, transmembrane protein seen on Western blots as a twin band of 54/58 kDa, expressed in gastric mucosa and in several types of cancer. The other is a soluble protein s-CA IX of 50/54 kDa, which is released into the culture medium or into the body fluids, most likely by proteolytic cleavage of the extracellular part from transmembrane and intracellular sequences. While TC media of CA IX-positive tumour cell lines or short-term cultures of tumour explants contain a relatively high concentration of s-CA IX (20-50 ng ml(-1)), the level of this antigen in blood serum and urine of renal clear cell carcinoma patients is about 1000 x lower. The concentration of CA IX in the blood and in urine varies within wide limits and there is no obvious correlation with tumour size. After nephrectomy, s-CA IX is cleared from the blood within a few days. Only an extremely low concentration of CA IX was detectable in the sera and in urine of control individuals.


Asunto(s)
Antígenos de Neoplasias/sangre , Antígenos de Neoplasias/orina , Anhidrasas Carbónicas/sangre , Anhidrasas Carbónicas/orina , Carcinoma de Células Renales/enzimología , Neoplasias Renales/enzimología , Proteínas de Neoplasias/sangre , Proteínas de Neoplasias/orina , Adulto , Anciano , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/orina , Northern Blotting , Anhidrasa Carbónica IX , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Membrana Celular/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Pronóstico , Células Tumorales Cultivadas
15.
Physiol Res ; 52(4): 433-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12899655

RESUMEN

The pathogenesis of arterial hypertension in autosomal dominant polycystic kidney disease (ADPKD) is complex and likely dependent on interaction of hemodynamic, endocrine and neurogenic factors. We decided to evaluate the role of endothelin (ET1) and nitric oxide (NO) in the regulation of arterial blood pressure (BP) and to determine plasma levels of ET1 and NO in the group of patients with ADPKD. The ADPKD group (18 patients, 6 men + 12 women, mean age 44.6+/-11.7 years, with creatinine clearancecorrig > 1.1 ml/s) was compared with a control group of 27 healthy volunteers of comparable age. Plasma levels of ET1 assessed by direct RIA determination in the group of ADPKD patients (11.03+/-1.8 fmol/ml) were significantly increased (p<0.001) in comparison with the control group (2.66+/-0.58 fmol/ml), while no significant differences were observed between normotensive and hypertensive patients in the ADPKD group. Serum levels of NO were evaluated according to the determination of serum levels of their metabolites - nitrites/nitrates. Serum levels of NO in the group of ADPKD patients (39.85+/-.38 micro mol/l) were significantly higher (p<0.05) in comparison with the control group (22.7+/-1.20 micro mol/l), whereas in the ADPKD group no significant differences were observed between normotensive and hypertensive patients. Thus, our study supports the concept of complex alteration of both vasoconstrictor and vasodilator systems in the pathogenesis of arterial hypertension in ADPKD.


Asunto(s)
Endotelina-1/fisiología , Hipertensión/etiología , Óxido Nítrico/fisiología , Riñón Poliquístico Autosómico Dominante/complicaciones , Adulto , Anciano , Antioxidantes/metabolismo , Enfermedad Crónica , Creatina/metabolismo , Endotelina-1/sangre , Femenino , Tasa de Filtración Glomerular , Humanos , Hipertensión/enzimología , Hipertensión/fisiopatología , Peroxidación de Lípido/fisiología , Masculino , Persona de Mediana Edad , Óxido Nítrico/sangre , Riñón Poliquístico Autosómico Dominante/enzimología , Riñón Poliquístico Autosómico Dominante/fisiopatología
16.
Rozhl Chir ; 82(12): 645-51, 2003 Dec.
Artículo en Checo | MEDLINE | ID: mdl-14746235

RESUMEN

The paper describes the advantages and disadvantages of the laparoscopic operations, the number of which steadily rises in urology. The laparoscopic surgery is considered to be a benefit regarding the short postoperative hospital stay, painless postoperative course, and virtually non-existing postoperative paralytic ileus. As disadvantage are deemed the long learning curve for the operating personal, and high economical costs, which could be cut down only if short off-work period in productive population is included. In the paper, the pathophysiological guidelines are outlined and emphasized during the laparoscopic operation, which the surgical and anesthesiological teams have to have in mind. On the own cohort of patients, the numbers and types of operations are described, which have been done at our department.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Urológicos , Adulto , Anciano , Humanos , Laparoscopía/efectos adversos , Persona de Mediana Edad , Procedimientos Quirúrgicos Urológicos/efectos adversos
17.
Vnitr Lek ; 48(11): 1011-6, 2002 Nov.
Artículo en Checo | MEDLINE | ID: mdl-12577451

RESUMEN

Case-control study comparing 81 patients with chronic renal failure (CRF) with 58 patients without renal disease who were evaluated by endoscopy of upper and/or lower gastrointestinal tract (GIT) for gastrointestinal bleeding or dyspepsia. The success of endoscopic examinations was the same in both groups. Patients with CRF more often underwent endoscopic examination because of gastrointestinal bleeding and they presented more often by hematochezia. Patients with CRF were more often found to have hemorrhagic gastropathy or duodenopathy and angiodysplasia of upper and lower GIT. However, duodenal ulcer was significantly more common in the control group without renal disease. Incidence of Helicobacter Pylori infection was low in both groups.


Asunto(s)
Endoscopía Gastrointestinal , Hemorragia Gastrointestinal/diagnóstico , Fallo Renal Crónico/complicaciones , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Estudios Retrospectivos
18.
J Org Chem ; 66(13): 4595-600, 2001 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-11421779

RESUMEN

Heptakis(2,3,6-tri-O-allyl)-beta-cyclodextrin 2 was converted to heptakis[2,3,6-tri-O-(2,3-dihydroxypropyl)]-beta-cyclodextrin 3 by osmium tetroxide-catalyzed dihydroxylation. A diastereomeric mixture of 3 was treated with sodium periodate followed by sodium borohydride to give heptakis[2,3,6-tri-O-(2-hydroxyethyl)]-beta-cyclodextrin 5 in 86% yield. Compound 5 could be quantitatively transformed into heptakis(2,3,6-tri-O-carboxymethyl)-beta-cyclodextrin 6 by TEMPO-mediated oxidation. The same reaction sequence was also applied to heptakis(2,6-di-O-allyl-3-O-methyl)-beta-cyclodextrin 8, heptakis(2,3-di-O-allyl-6-O-methyl)-beta-cyclodextrin 12, and heptakis(2,3-di-O-allyl-6-O-butyl)-beta-cyclodextrin 16; the analogous corresponding hydroxyethyl and carboxymethyl derivatives were isolated in high yields. All products were proved to be chemically uniform.


Asunto(s)
Ciclodextrinas/síntesis química , Aditivos Alimentarios/síntesis química , beta-Ciclodextrinas , Ciclodextrinas/química , Aditivos Alimentarios/química
19.
Am J Pathol ; 158(3): 905-19, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11238039

RESUMEN

An acidic extracellular pH is a fundamental property of the malignant phenotype. In von Hippel-Lindau (VHL)-defective tumors the cell surface transmembrane carbonic anhydrase (CA) CA9 and CA12 genes are overexpressed because of the absence of pVHL. We hypothesized that these enzymes might be involved in maintaining the extracellular acidic pH in tumors, thereby providing a conducive environment for tumor growth and spread. Using Northern blot analysis and immunostaining with specific antibodies we analyzed the expression of CA9 and CA12 genes and their products in a large sample of cancer cell lines, fresh and archival tumor specimens, and normal human tissues. Expression was also analyzed in cultured cells under hypoxic conditions. Expression of CA IX and CA XII in normal adult tissues was detected only in highly specialized cells and for most tissues their expression did not overlap. Analysis of RNA samples isolated from 87 cancer cell lines and 18 tumors revealed high-to-moderate levels of expression of CA9 and CA12 in multiple cancers. Immunohistochemistry revealed high-to-moderate expression of these enzymes in various normal tissues and multiple common epithelial tumor types. The immunostaining was seen predominantly on the cell surface membrane. The expression of both genes was markedly induced under hypoxic conditions in tumors and cultured tumor cells. We conclude that the cell surface trans-membrane carbonic anhydrases CA IX and CA XII are overexpressed in many tumors suggesting that this is a common feature of cancer cells that may be required for tumor progression. These enzymes may contribute to the tumor microenvironment by maintaining extracellular acidic pH and helping cancer cells grow and metastasize. Our studies show an important causal link between hypoxia, extracellular acidification, and induction or enhanced expression of these enzymes in human tumors.


Asunto(s)
Anhidrasas Carbónicas/biosíntesis , Hipoxia de la Célula , Concentración de Iones de Hidrógeno , Neoplasias/enzimología , Neoplasias/etiología , Biomarcadores de Tumor/biosíntesis , Northern Blotting , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/inmunología , Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/enzimología , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , División Celular , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioblastoma/enzimología , Humanos , Inmunohistoquímica , Neoplasias Renales/diagnóstico , Neoplasias Renales/enzimología , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Modelos Biológicos , Neoplasias/genética , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Células Tumorales Cultivadas
20.
Br J Cancer ; 82(11): 1808-13, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10839295

RESUMEN

MN/CA IX is a cell surface protein, strongly associated with several types of human carcinomas. It exerts activity of carbonic anhydrase and capacity of binding to cell surface receptors. In the present work, we used affinity purified MN/CA IX protein to demonstrate that the cells adhere to immobilized MN/CA IX and that the monoclonal antibody M75 abrogates cell attachment to MN/CA IX. Using synthetic oligopeptides, we identified M75 epitope and located it in the proteoglycan domain, which contains a sixfold tandem repeat of six amino acids GEEDLP. From phage display library of random heptapeptides we identified and chemically synthesized those which compete for the epitope with M75 and inhibit adhesion of cells to MN/CA IX. These heptapeptides might serve as lead compounds for drug design.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Adhesión Celular , Mapeo Epitopo , Proteínas de Neoplasias/metabolismo , Secuencia de Aminoácidos , Moléculas de Adhesión Celular/química , Moléculas de Adhesión Celular/inmunología , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática , Humanos , Datos de Secuencia Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/inmunología , Células Tumorales Cultivadas
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