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1.
J Phys Condens Matter ; 33(2): 024001, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-32906096

RESUMEN

We present a model equation of states for expanded metals, which contains a pressure term due to a screened-Coulomb potential with a screening parameter reflecting the Mott-Anderson metal-to-nonmetal transition. As anticipated almost 80 years ago by Zel'dovich and Landau, this term gives rise to a second coexistence line in the phase diagram, indicating a phase separation between a metallic and a nonmetallic liquid.

2.
Philos Trans A Math Phys Eng Sci ; 368(1914): 941-65, 2010 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-20123742

RESUMEN

In a letter to one of the authors, Sir Nevill Mott, then in his tenth decade, highlighted the fact that the statement '... a metal conducts, and a non-metal doesn't' can be true only at the absolute zero of temperature, T=0 K. But, of course, experimental studies of metals, non-metals and, indeed, the electronic and thermodynamic transition between these canonical states of matter must always occur above T=0 K, and, in many important cases, for temperatures far above the absolute zero. Here, we review the issues-theoretical and experimental-attendant on studies of the metal to non-metal transition in doped semiconductors at temperatures close to absolute zero (T=0.03 K) and fluid chemical elements at temperatures far above absolute zero (T>1000 K). We attempt to illustrate Mott's insights for delving into such complex phenomena and experimental systems, finding intuitively the dominant features of the science, and developing a coherent picture of the different competing electronic processes. A particular emphasis is placed on the idea of a 'Mott metal to non-metal transition' in the nominally metallic chemical elements rubidium, caesium and mercury, and the converse metallization transition in the nominally non-metal elements hydrogen and oxygen. We also review major innovations by D. A. Goldhammer (Goldhammer 1913 Dispersion und absorption des lichtes) and K. F. Herzfeld (Herzfeld 1927 Phys. Rev. 29, 701-705. (doi:10.1103/PhysRev.29.701)) in a pre-quantum theory description of the metal-non-metal transition, which emphasize the pivotal role of atomic properties in dictating the metallic or non-metallic status of the chemical elements of the periodic table under ambient and extreme conditions; a link with Pauling's 'metallic orbital' is also established here.

3.
Lab Invest ; 81(11): 1553-63, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11706063

RESUMEN

The human monoclonal antibody SC-1 was isolated from a patient with a diffuse-type adenocarcinoma of the stomach using somatic cell hybridization. The immunoglobulin (Ig)M antibody reacts specifically with diffuse- (70%) and intestinal-type (25%) gastric adenocarcinoma and induces apoptosis in vitro and in vivo. When used in clinical trials with stomach carcinoma patients, significant apoptotic and regressive effects in primary tumors have been observed with the antibody SC-1. The SC-1 receptor is a new 82 kd membrane-bound isoform of glycosylphosphatidylinositol (GPI)-linked CD55 (decay-accelerating factor, DAF). CD55 is known to protect cells from lysis through autologous complement and is coexpressed with the ubiquitously distributed 70 kd isoform. The SC-1-specific CD55 isoform is up-regulated shortly after antibody binding, followed by an internalization of the antibody/receptor-complex, whereas the membranous expression of wild-type CD55 remains unchanged. The apoptotic process is marked by cleavage of cytokeratin 18, indicating the involvement of caspase-6 in the apoptotic process. In contrast to other apoptotic pathways, a cleavage of poly(ADP-ribose)polymerase (PARP) is not observed. The expression of the cell-cycle regulator c-myc becomes up-regulated, whereas expression of topoisomerase IIalpha is down-regulated. Induction of apoptosis leads to an increase in the internal Ca(2+) concentration, which is not necessary for the apoptotic process but for the transport of newly synthesized SC-1-specific CD55 isoform to the membrane.


Asunto(s)
Adenocarcinoma , Anticuerpos Monoclonales/farmacocinética , Antineoplásicos/farmacocinética , Apoptosis/inmunología , Antígenos CD55/biosíntesis , Neoplasias Gástricas , Anticuerpos Monoclonales Humanizados , Antígenos CD55/análisis , Antígenos CD55/inmunología , Calcio/metabolismo , Caspasa 3 , Caspasa 6 , Inhibidores de Caspasas , Membrana Celular/fisiología , Citoplasma/fisiología , Citometría de Flujo , Células HeLa , Humanos , Queratinas/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo
4.
Hum Antibodies ; 10(2): 83-90, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11673663

RESUMEN

Phosphorylation and activation of caspases play an important role in the induction of apoptosis. During tumor specific apoptosis, induced by the human monoclonal antibody SC-1, tyrosine phosphorylation and serine dephosphorylation of several proteins is observed. In this paper we describe the identification of two dephosphorylated proteins as heterogeneous nuclear ribonucleoproteins A1 and A2 (hnRNP A1, hnRNP A2). The dephosphorylation of these proteins is important for apoptosis since the amount of apoptotic cell death can be decreased by the specific serine/threonine phosphatase inhibitor okadaic acid. We also investigated the effect of serine kinase inhibitor H7 on SC-1 induced apoptosis, which leads to a dose dependent increase in apoptosis. We could also show that 24 hours after the induction of apoptosis the hnRNP A1 protein is cleaved into different cleavage products. Further, we found a decreased expression of caspase-2 in early apoptosis signalling and an overexpression 24 hours after induction of apoptosis. Our results show that the phosphorylation status of the hnRNP A1 and A2 plays a significant role in early SC-1 induced apoptosis signalling and further indicate the role of caspase activation during the apoptotic process.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Apoptosis/inmunología , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B , Ribonucleoproteínas/antagonistas & inhibidores , Secuencia de Aminoácidos , Anticuerpos Monoclonales Humanizados , Caspasa 2 , Caspasas/metabolismo , ADN Complementario , Ribonucleoproteína Nuclear Heterogénea A1 , Ribonucleoproteínas Nucleares Heterogéneas , Humanos , Hidrólisis , Fosforilación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribonucleoproteínas/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Neoplasias Gástricas/inmunología , Células Tumorales Cultivadas
5.
Lab Invest ; 81(8): 1097-108, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502861

RESUMEN

The germline coded human monoclonal IgM antibody 103/51 was isolated from a gastric carcinoma patient. This antibody binds to a 130-kd membrane molecule and has a mitotic effect on tumor cells in vitro. To characterize the target, we sequenced the protein and showed that the antibody binds to the cysteine-rich fibroblast growth factor receptor (CFR)-1, which is highly homologous to MG-160 and the E-selectin-ligand (ESL)-1. The epitope was determined by glycosidase-digestion experiments to be an N-linked carbohydrate side chain. Immunohistochemistry was used to investigate the tissue distribution of CFR-1. Different healthy tissues were tested and only the collecting tubes of the kidney, the Golgi apparatus, and the glomerular and fascicular zones of the adrenal gland stained positive. However, on malignant tissue the receptor is overexpressed in nearly all tested stomach cancers (12 of 15) and other tested carcinomas (13 of 15). Most interestingly, the receptor is also present in Helicobacter pylori gastritis and gastric dysplasia, but absent on uninflamed stomach mucosa. This restricted tissue pattern indicates that antibody 103/51 reacts with a membrane-bound variant of CFR-1, which is mainly expressed on transformed cells and precursor lesions and is essential for proliferation processes. The possible activity of antibody 103/51 as an activating ligand in these proliferative changes of gastric epithelial mucosa is discussed.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Receptores de Factores de Crecimiento de Fibroblastos/inmunología , Adenocarcinoma/química , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/aislamiento & purificación , Autoanticuerpos/inmunología , Línea Celular , Epítopos/inmunología , Mucosa Gástrica/química , Glicósido Hidrolasas/química , Humanos , Inmunohistoquímica , Ratones , Oligonucleótidos Antisentido , Receptores de Factores de Crecimiento de Fibroblastos/genética , Receptores de Factores de Crecimiento de Fibroblastos/aislamiento & purificación , Neoplasias Gástricas/química , Distribución Tisular , Transfección
6.
Appl Radiat Isot ; 53(4-5): 617-24, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11003498

RESUMEN

A density measurement technique, appropriate for the determination of average densities ranging from 10 to 100 kg/m3, is described. It can be applied for determining the density of foams or the humidity of pressurized gases. The technique makes use of the density dependent positron range in the measured matter. The used coincidence detection technique known from positron emission tomography, benefits from the back to back emitted annihilation quanta to determine the region of emission. A tailored detector system was checked in experiments with solid foam blocks and is ready for applications now.

7.
Zentralbl Chir ; 125 Suppl 1: 37-40, 2000.
Artículo en Alemán | MEDLINE | ID: mdl-10929645

RESUMEN

The human monoclonal antibody SC-1 was isolated from a patient with a diffuse-type adenocarcinoma of the stomach and induces apoptosis of stomach carcinoma cells by binding a stomach-carcinoma-associated isoform of CD55/DAF-B. In a first clinical trial with 20 patients with poorly differentiated stomach adenocarcinoma of diffuse-type received 20 and 30 mg of purified SC-1 antibody intravenously, followed 24 or 48 h later by gastrectomy and lymphadenectomy. In 90% of the cases a significant induction of apoptotic activity was measured in primary tumors as compared with earlier biopsy material and in 50% of the patients a significant regression of tumor mass could even be determined histopathologically. No toxic crossreactivity was observed with normal tissue or organs of patients. These data show, that the human monoclonal antibody SC-1, which induces tumorspecific apoptosis, can be successfully used for adjuvant therapy.


Asunto(s)
Adenocarcinoma/terapia , Anticuerpos Monoclonales/inmunología , Apoptosis , Inmunoterapia , Neoplasias Gástricas/terapia , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biopsia , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Células Tumorales Cultivadas/inmunología
8.
Gesundheitswesen ; 62(7): 376-82, 2000 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-10955004

RESUMEN

Object of this investigation was to evaluate attitudes and opinions of general practitioners, internal specialists and pharmacists with regard to vaccination. At the same time we investigated the actual vaccination state of these groups and of the medical staff and pharmacy staff. Physicians and pharmacists answered by using a four-page written questionnaire. The vaccination state was evaluated by a single-page questionnaire. Analyses were made by using the statistical program SPSS. The 161 physicians and 188 pharmacists participating in this study generally agree that the risk of infection in practice and pharmacy is not significant. The best vaccine protection in these groups was observed for tetanus. An effective inoculation against this pathogen was documented by 79.4% of physicians and 63.3% of pharmacists. 73.4% of physicians had also a protection against hepatitis B. All other vaccinations were documented as actually protective only in 6-55% of the cases. Physicians and pharmacists agree that their staff should have a vaccination against tetanus, diphtheria and poliomyelitis, followed by hepatitis B and influenza. The vaccination state of medical staff and pharmacy-staff does not attain the demanded standard. It shows levels of 3-70%. Further education in vaccination is more often practised by pharmacists and their staff than by physicians and medical staff. Physicians are more active in advising patients about vaccination than pharmacists and patients rather consult their doctor than a pharmacist to give them vaccination advice. There is still a need for motivation of physicians and pharmacists to be an example for their patients and clients respectively. In addition, more of public information could be helpful.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Farmacéuticos/estadística & datos numéricos , Técnicos de Farmacia/estadística & datos numéricos , Asistentes Médicos/estadística & datos numéricos , Médicos/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Adulto , Femenino , Alemania , Humanos , Inmunización , Masculino , Persona de Mediana Edad
9.
Lab Invest ; 79(11): 1377-84, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10576208

RESUMEN

In osteoarthritis (OA), the synovial tissue exhibits a nonfollicular inflammatory infiltration with a characteristic arrangement of lymphocytes and plasma cells. These arrangements are either small perivascular aggregates with plasma cells surrounding the lymphocytes or small groups of plasma cells, located in the vicinity of small blood vessels. These patterns suggest that B lymphocytes directly differentiate into plasma cells. To understand the B-cell response in OA, we analyzed the V(H) genes from B cells of synovial tissue of nine OA patients (average age, 71.5+/-10.5 years; six female and three male). V(H) gene repertoires were determined from RNA prepared from tissue cryosections and from DNA of single isolated B lymphocytes and plasma cells. The inflammatory infiltrate was analyzed immunohistochemically by detecting CD20, Ki-M4 (follicular dendritic cells), CD4, IgG, IgM, IgA, Ki-67, and by simultaneous demonstration of the plasma-cell-specific antigen CD138 (syndecan-1) and factor VIII. The molecular data demonstrate B cells with a high number of somatic mutations (average, 16.5 to 19.8), and high ratios of replacement to silent mutations in the small lymphocytic/plasmacellular aggregates of OA. In the tissue cryosections, the values of the sigmaR/sigmaS at the complementarity determining regions were 5.3 and 2.0 in the framework regions. For both the isolated B lymphocytes and plasma cells, the value of this ratio in the complementarity determining regions was 3.5. In the framework regions, the values of this ratio were 2.0 for the isolated B cells and 1.8 for the plasma cells. B lymphocytes and plasma cells exhibited a distribution not described thus far. Two patterns of B-cell distribution could be observed: (a) Centrally located CD20+ B and CD4+ and CD8+ T lymphocytes were surrounded directly by IgG (predominantly) or IgA and IgM plasma cells. No proliferating Ki-67-positive cells and no follicular dendritic cells (germinal centers) could be detected in the aggregates; (b) Plasma cells (predominantly IgG) were located directly near endothelial cells of small blood vessels. The finding of highly mutated V(H) genes in B lymphocytes and the characteristic arrangement of B lymphocytes and plasma cells suggests that B cells, which participate in OA synovialitis, have undergone germinal center reaction at different sites. This may explain the low inflammatory infiltration without germinal centers in OA, which is a feature of this primarily degenerative joint disease.


Asunto(s)
Linfocitos B/patología , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Mutación/fisiología , Osteoartritis/patología , Sinovitis/patología , Anciano , Anciano de 80 o más Años , Formación de Anticuerpos , Especificidad de Anticuerpos , Antígenos/inmunología , Linfocitos B/inmunología , Secuencia de Bases/genética , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Osteoartritis/genética , Osteoartritis/inmunología , Membrana Sinovial/patología , Sinovitis/genética , Sinovitis/inmunología
10.
Cancer Res ; 59(20): 5299-306, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10537313

RESUMEN

The human monoclonal antibody SC-1 induces apoptosis of stomach carcinoma cells and is currently used in a clinical Phase II trial. The antibody binds to a target molecule that is preferentially expressed on diffuse- and intestinal-type stomach cancer cells and shows a very restricted expression on other normal and malignant tissues. In this paper, we show that the SC-1 receptor is a stomach carcinoma-associated isoform of CD55 [membrane-bound decay-accelerating factor (DAF)-B] with a relative molecular mass of approximately 82 kDa. The antigenic site of SC-1 is an N-linked carbohydrate residue. Cross-linking of the DAF receptor increases apoptotic activity. SC-1 binding induces tyrosine phosphorylation of three proteins of approximately 60, 75, and 110 kDa, whereas a serine residue of an approximately 35-kDa protein is dephosphorylated. Expression of caspase-3 (CPP32) and caspase-8 (FLICE) is elevated, and activation of these caspases occurs. These data show that a tumor-specific variant form DAF is involved in apoptosis and can be used for adjuvant therapeutical purposes on gastric carcinoma.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Anticuerpos Antineoplásicos/metabolismo , Apoptosis , Antígenos CD55/fisiología , Glicosilfosfatidilinositoles/fisiología , Neoplasias Gástricas/inmunología , Anticuerpos Antineoplásicos/aislamiento & purificación , Antígenos CD55/aislamiento & purificación , Caspasas/metabolismo , Glicósido Hidrolasas/farmacología , Humanos , Fosfatidilinositol Diacilglicerol-Liasa , Fosforilación , Neoplasias Gástricas/patología , Transfección , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/farmacología
11.
Int J Cancer ; 81(2): 229-35, 1999 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-10188724

RESUMEN

Colonization of the bacterium Helicobacter pylori of gastric mucosa plays an important role in stomach carcinogenesis, while the gastric mucosa and nearby lymphoid tissue are active sites of humoral immunity against both bacteria and tumor. In a broad study on the humoral immunity of stomach-cancer patients (5 patients with diffuse- and intestinal-type stomach carcinoma), we immortalized spleen cells by using human hybridoma technology and isolated 11 hybrid clones (9 IgM, 1 IgG and 1 IgA) which react with defined proteins on different stomach-cancer cells and, interestingly, also with distinct proteins on H. pylori; 4 of these antibodies are mitogenic and stimulate the proliferation of stomach-cancer cells in vitro. Furthermore, immunohistochemical studies define these 4 clearly as autoantibodies, in view of their reactivity to normal epithelial cells. Sequence analysis of the genes for the immunoglobulin heavy (V(H)) and light (V(L)) chain variable regions revealed that most of the human antibodies belong to the V(H)3, Vlambda I and III gene families (DP-49, DPL-5 and DPL-23) and are germ-line configured.


Asunto(s)
Autoanticuerpos/análisis , Helicobacter pylori/aislamiento & purificación , Mitógenos/inmunología , Neoplasias Gástricas/microbiología , Autoanticuerpos/genética , Secuencia de Bases , Western Blotting , Línea Celular , Reacciones Cruzadas , Humanos , Hibridomas/inmunología , Inmunohistoquímica , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Neoplasias Gástricas/inmunología , Sales de Tetrazolio
12.
Clin Exp Immunol ; 115(1): 168-75, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9933438

RESUMEN

The mutational pattern of IgVH and IgVL genes from synovial tissue B cell hybridomas (n = 8) of patients (n = 4) with rheumatoid arthritis (RA) was analysed, which had been produced by the electrofusion technique without prior in vitro stimulation. The molecular data were correlated with immunohistopathological data and parameters of local disease activity. The IgVH genes of the B cell hybridomas belonged to the VH3 family (DP42; DP47, n = 2; DP53), the VH1 family (DP75), the VH4 family (DP71) and the VH5 family (DP73); 7/7 IgVH genes showed somatic mutations, the R/S ratio (CDR) was > 3 in 4/7 IgVH genes and the mean R/S ratio of all IgVH genes was 9.3 (CDR) and 1.0 (FR), suggesting an antigen-dependent selection. The IgVL/lambda genes belonged to the Vlambda1 family (DPL2, DPL5, DPL8nf), the Vlambda2 family (DPL11, n = 2) and to the Vlambda6 family (IGLV6S1); 6/6 IgVL genes showed somatic mutations, the R/S ratio (CDR) was > 3 in 3/6 IgVL genes and the mean R/S ratio of all IgVL was 3.0 (CDR) and 2.3 (FR), suggesting an antigen-dependent selection. The synovial tissue exhibited germinal centres in the follicles (3/4), with the unique distribution of Ki-M4+ follicular dendritic cells and Ki-67+ proliferating cells and a dominance of IgA+ plasma cells (3/3). All patients were positive for RF in serum and exhibited severe local symptoms (swelling 4/4; warmth 4/4; effusion 2/4), whereas the hybridomas were negative for RF. Since B cell hybridomas showed hypermutation and affinity selection for IgVH and IgVL/lambda genes and the patients exhibited severe local symptoms with germinal centres in synovial tissue, this study indicates that an antigen-driven process is behind the B cell expansion in the synovial tissue of clinically affected joints. These mutated B hybridomas were negative for RF, thus suggesting that antigens different from RF are also involved in the local B cell expansion and in the chronic synovitis of RA.


Asunto(s)
Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Linfocitos B/citología , Hibridomas/química , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Ligeras de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Cadenas lambda de Inmunoglobulina/genética , Factor Reumatoide/análisis , Membrana Sinovial/patología , Anciano , Secuencia de Aminoácidos , Presentación de Antígeno , Artritis Reumatoide/patología , Secuencia de Bases , Ensayo de Inmunoadsorción Enzimática , Femenino , Genes de Inmunoglobulinas , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mutación
13.
Hepatogastroenterology ; 45(23): 1684-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9840129

RESUMEN

BACKGROUND/AIMS: Viral serum concentrations are considered to have a clinical, prognostic and epidemiological impact on patients with hepatitis C infection. The purpose of this study was to test whether quantitation of HCV-RNA is possible by PCR in combination with DNA-ELISA. METHODOLOGY: PCR with 25 to 35 cycles was performed with variable concentrations of cloned HCV-cDNA or the serum of patients with chronic hepatitis C. The amplified PCR-products were detected by agarose gel or by DNA-ELISA. RESULTS: The detection limit of PCR with DNA-ELISA or gel detection decreased with increasing numbers of PCR cycles. However, the correlation of the optical density of the DNA-ELISA with the HCV-cDNA concentration decreased with increasing numbers of PCR as well (r=0.8 vs. r=0.29; 25 vs. 35 PCR-cycles). HCV-RNA was found in the sera of 19 of 30 patients (63%) with chronic hepatitis C by gel detection and in 14 of 30 patients (47%) by DNA-ELISA subsequent to PCR with 35 cycles. CONCLUSIONS: The PCR/DNA-ELISA technique allows a semiquantitative determination of HCV-cDNA concentrations down to 103 genomes/ul. However, to obtain a reasonable sensitivity for HCV concentrations in the serum of patients with hepatitis C, the number of PCR cycles has to be increased to numbers too high to provide reliable quantification. Further studies should be done to evaluate whether the detection systems can be improved to obtain a sufficient sensitivity for quantitative HCV-PCR. A prerequisite for the use of PCR in combination with quantifiable detection systems is that a PCR-cycle number is chosen that keeps amplification within the logarithmic phase.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática , Hepacivirus/genética , Hepatitis C Crónica/virología , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , ADN Viral/análisis , Hepacivirus/aislamiento & purificación , Humanos , Sensibilidad y Especificidad
14.
Hepatology ; 28(6): 1687-95, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9828236

RESUMEN

The prognosis of chronic hepatitis C virus (HCV) infection is still ill-defined. The present study prospectively evaluated mortality and complications in a large cohort of patients with chronic hepatitis C. The study included 838 anti-HCV and HCV-RNA-positive patients who were followed for 50.2 +/- 26.9 months (mean +/- SD; range, 6-122 months) in a prospective protocol. During follow-up, 62 patients died (31 from liver disease and 31 from other causes), and 12 patients needed liver transplantation. When compared with a matched general population, hepatitis C increased mortality mainly when cirrhosis was present and in patients who were less than 50 years old at study entry. During follow-up, a further 30 patients developed nonlethal complications of cirrhosis. By multivariate regression, survival was decreased by cirrhosis, long disease duration, history of intravenous drug abuse, and excessive alcohol consumption, whereas interferon therapy improved survival. Alanine transaminase (ALT), bilirubin, sex, and genotype had no effect on survival. The risk of hepatocellular carcinoma (HCC) (n = 17) was increased by cirrhosis and to a lesser degree by long disease duration and high bilirubin, whereas interferon therapy, genotype, and other factors had no effect. Chronic hepatitis C is a disease with considerable mortality and morbidity when cirrhosis is present at diagnosis. Patients who acquire the infection early in life have a markedly increased mortality even when cirrhosis is absent at diagnosis. The age at diagnosis therefore should play a major role in therapeutic considerations. The present data also suggest that interferon therapy has a long-term clinical benefit, although it did not reduce the risk of liver cancer.


Asunto(s)
Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/mortalidad , Adulto , Distribución por Edad , Causas de Muerte , Estudios de Cohortes , Femenino , Hepatitis C Crónica/terapia , Humanos , Interferones/uso terapéutico , Cirrosis Hepática/etiología , Neoplasias Hepáticas/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Análisis de Supervivencia
16.
Dig Dis Sci ; 43(7): 1562-5, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9690395

RESUMEN

The present study prospectively evaluated the value of liver biopsy in patients with chronic hepatitis B (N=75) and C (N=135) prior to interferon therapy. Biopsy specimens revealed cirrhosis in 26% of patients with hepatitis B and 30% with hepatitis C. Although cirrhosis was not predictable by laboratory values in individual patients mean gamma-GT, alkaline phosphatase, and bilirubin levels were significantly higher in patients with cirrhosis compared to those without. Since cirrhosis significantly impairs the response rate to interferon therapy in hepatitis C but not in hepatitis B, liver biopsy is important for the management of chronic hepatitis C infection. In 88% of patients with serum HBV-DNA, irrespective of the serum HBeAg status, chronic active hepatitis was seen. Similarly, chronic active hepatitis was found in 84% of patients with elevated aminotransferases and hepatitis C antibodies. Thus, chronic active hepatitis was diagnosed in the majority of cases with chronic viral hepatitis, showing that this histopathological diagnosis is of little additional value for the recommendation on interferon treatment in these patients. However, none of the other grading systems of liver biopsy specimens described so far have been evaluated for their ability to predict overall prognosis or response rates to interferon therapy. Therefore, the physician is presently left with the questionable value of a procedure with well-known risks and costs in patients suitable for interferon treatment. Hence, prospective randomized controlled studies to evaluate histopathological grading systems are urgently needed to redefine the necessity of liver biopsy in this routine clinical setting.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/patología , Hepatitis C Crónica/patología , Interferones/uso terapéutico , Hígado/patología , Biopsia , Hepatitis B Crónica/terapia , Hepatitis C Crónica/terapia , Humanos , Cirrosis Hepática/patología , Estudios Prospectivos
17.
Arch Biochem Biophys ; 354(1): 172-80, 1998 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9633613

RESUMEN

Betaine and myoinositol are compatible organic osmolytes which are specifically accumulated by cells exposed to hyperosmotic medium. A role for compatible organic osmolytes in the regulation of immune function for rat liver macrophages has been described recently. This report describes an osmolyte strategy in human peripheral blood monocytes and human peripheral blood-derived macrophages. Hyperosmotic (405 mOsm) exposure of monocytes and macrophages led to an upregulation of betaine/gamma-amino-n-butyric acid (GABA) transporter BGT-1 and sodium-dependent myoinositol transporter SMIT in mRNA levels within 6 to 12 h. Induction of BGT-1 and SMIT mRNA occurred regardless of whether hyperosmolarity was induced by addition of NaCl (50 mM) or raffinose (100 mM). Betaine (5 mM) inhibited upregulation of BGT-1 as well as SMIT mRNA. After hyperosmotic (405 mOsm) exposure uptake of betaine and myoinositol was increased up to 10-fold compared to normoosmotic conditions. Hypoosmotic exposure led to a rapid efflux of betaine and myoinositol. Treatment of cells with the pyridinyl imidazole SB 203580 (10 microM), a specific inhibitor of p38 MAP kinase, inhibited the hyperosmolarity-induced increase in BGT-1 and SMIT mRNA as well as betaine and myoinositol uptake by 45-70%. The data show that human peripheral blood monocytes and human peripheral blood-derived macrophages use betaine and myoinositol are compatible organic osmolytes when exposed to osmotic stress and that p38MAPK is involved in hyperosmolarity-induced upregulation of osmolyte transporters BGT-1 and SMIT.


Asunto(s)
Betaína/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Proteínas Portadoras/biosíntesis , Proteínas de Choque Térmico/biosíntesis , Inositol/metabolismo , Macrófagos/fisiología , Proteínas de la Membrana , Proteínas Quinasas Activadas por Mitógenos , Monocitos/fisiología , Simportadores , Proteínas Portadoras/genética , Proteínas Portadoras/fisiología , Medios de Cultivo/farmacología , Proteínas Transportadoras de GABA en la Membrana Plasmática , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/fisiología , Humanos , Macrófagos/metabolismo , Monocitos/metabolismo , Concentración Osmolar , Presión Osmótica , ARN Mensajero/biosíntesis , Ácido gamma-Aminobutírico/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos
18.
Oncol Rep ; 5(3): 549-52, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9538151

RESUMEN

In a first clinical trial with the apoptosis-inducing human antibody SC-1 eight patients with poorly differentiated stomach adenocarcinoma of diffuse-type received 20 or 30 mg of purified SC-1 antibody intravenously, followed 24 or 48 h later by gastrectomy and lymphadenectomy. In seven cases a significant induction of apoptotic activity was measured in primary tumors as compared with earlier biopsy material and in five patients a significant regression of tumor mass could be determined histopathologically. No toxic crossreactivity was observed with normal tissue or organs of patients.


Asunto(s)
Adenocarcinoma/terapia , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Inmunoterapia , Neoplasias Gástricas/terapia , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Adulto , Anciano , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Monoclonales Humanizados , Antineoplásicos/aislamiento & purificación , Terapia Combinada , Fragmentación del ADN , Femenino , Gastrectomía , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología , Resultado del Tratamiento
20.
Oncol Rep ; 5(1): 35-40, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9458378

RESUMEN

Stomach cancer is one of the most frequently occurring cancers worldwide, with a very poor prognosis, even after complete gastrectomy. We describe here an alternative therapeutical approach using a human monoclonal antibody (SC-1), which was isolated from a patient with diffuse-type gastric adenocarcinoma. We demonstrate that the antibody significantly reduces stomach cancer growth in vivo, by inducing tumor-specific apoptosis and that the antibody, even delivered in high doses, shows no toxic crossreactivity to other organs or tissues. The data presented here show that tumor-specific apoptosis can be induced and they give rise to the hope that human monoclonal antibodies with biological activity might present a completely new type of adjuvant cancer therapy.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Apoptosis , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/terapia , Adenocarcinoma/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Secuencia de Bases , División Celular , Fragmentación del ADN , Genes de Inmunoglobulinas , Humanos , Cadenas Pesadas de Inmunoglobulina/química , Inmunoterapia , Hígado/patología , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Neoplasias Gástricas/patología , Trasplante Heterólogo
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