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1.
Zhonghua Fu Chan Ke Za Zhi ; 58(7): 516-525, 2023 Jul 25.
Artículo en Zh | MEDLINE | ID: mdl-37474325

RESUMEN

Objective: To investigate the natural regression and related factors of high-grade squamous intraepithelial lesion (HSIL) in the cervix of childbearing age women, and to evaluate the applicability of conservative management for future fertility needs. Methods: This study included 275 patients of reproductive age with fertility needs, who were diagnosed as HSIL by biopsy from April 30, 2015 to April 30, 2022, including 229 cases (83.3%) cervical intraepithelial neoplasia (CIN) Ⅱ and 46 cases (16.7%) CIN Ⅱ-Ⅲ. They were followed-up without immediate surgery in the First Affiliated Hospital of Nanjing Medical University. The median follow-up time was 12 months (range: 3-66 months). The regression, persistence and progression of lesions in patients with HSIL were analyzed during the follow-up period, the influencing factors related to regression and the time of regression were analyzed. Results: (1) Of the 275 HSIL patients, 213 cases (77.5%, 213/275) experienced regression of the lesion during the follow-up period. In 229 CIN Ⅱ patients, 180 cases (78.6%) regressed, 21 cases (9.2%) persisted, and 28 cases (12.2%) progressed. In 46 CIN Ⅱ-Ⅲ patients, 33 cases (71.7%) regressed, 12 cases (26.1%) persisted, and 1 case (2.2%) progressed to invasive squamous cell carcinoma stage Ⅰ a1. There was no significant difference in the regression rate between the two groups (χ2=1.03, P=0.309). (2) The average age at diagnosis, age <25 years old at diagnosis were independent influencing factor of HSIL regression in univariate analysis (all P<0.05). There was no significant difference between HSIL regression and pathological grading, the severity of screening results, human papillomavirus (HPV) genotype, colposcopy image characteristics, number of biopsies during follow-up and pregnancy experience (all P>0.05). (3) The median regression times for patients aged ≥25 years and <25 years at diagnosis were 15 and 12 months, respectively. Kaplan-Meier analysis showed that age ≥25 years at diagnosis significantly increased the median regression time compared to <25 years (χ2=6.02, P=0.014). Conclusions: For HSIL patients of childbearing age, conservative management without immediate surgical intervention is preferred if CINⅡ is fully evaluated through colposcopy examination. Age ≥25 years at diagnosis is a risk factor affecting the prognosis of HSIL patients.


Asunto(s)
Carcinoma in Situ , Infecciones por Papillomavirus , Lesiones Intraepiteliales Escamosas de Cuello Uterino , Lesiones Intraepiteliales Escamosas , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Embarazo , Humanos , Femenino , Adulto , Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/patología , Biopsia , Colposcopía/métodos , Lesiones Intraepiteliales Escamosas/patología , Carcinoma in Situ/patología , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , Lesiones Intraepiteliales Escamosas de Cuello Uterino/patología
2.
Med Vet Entomol ; 34(2): 192-200, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31802518

RESUMEN

The heat shock protein 70 (HSPA) family and their genes have been studied in ticks and are considered as possible antigen candidates for the development of anti-tick vaccines. However, knowledge about their members, structure and function in ticks is incomplete. Based on our transcriptomic data, the full length of four HSPA genes in Haemaphysalis flava (Acari: Ixodidae) was cloned via rapid amplification of cDNA ends. The open reading frame of HSPA2A, HSPA2B, HSPA5 and HSPA9 was 1920, 1911, 1983 and 2088 bp in length, respectively. Three family signatures and one localization motif were in the encoding proteins. HSPA2A and HSPA2B were predicted to be located at cytoplasm/nucleus, whereas HSPA5 and HSPA9 were at endoplasmic reticulum and mitochondria, respectively. In silico simulation demonstrated that those proteins had distinct numbers of α-helixes, extended strands and coils, and different antigenic epitopes. Expression of HSPA5 and HSPA9 in the salivary gland was significantly higher in partially-engorged female adult ticks than the fully-engorged (P < 0.01) as shown by a quantitative polymerase chain reaction. Our data indicated that H. flava ticks had at least four HSPA genes encoding proteins with different cellular locations, structures and expression profiles, suggesting their diverse roles in tick biology.


Asunto(s)
Proteínas de Artrópodos/genética , Proteínas HSP70 de Choque Térmico/genética , Ixodidae/genética , Familia de Multigenes , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Clonación Molecular , Femenino , Proteínas HSP70 de Choque Térmico/química , Proteínas HSP70 de Choque Térmico/metabolismo , Ixodidae/metabolismo
3.
Zhonghua Xin Xue Guan Bing Za Zhi ; 45(6): 485-490, 2017 Jun 24.
Artículo en Zh | MEDLINE | ID: mdl-28648024

RESUMEN

Objective: To compare the efficacy and safety of Cardi-O-fix patent foramen ovale (PFO) occluder and Amplatzer PFO occluder for the treatment of patients with PFO. Methods: A total of 246 consecutive patients (105 males and 141 females) with PFO were prospectively enrolled from May 30, 2013 to March 30, 2015 in our hospital. PFO interventional closure was applied according to the anatomical structure of the disease and patients' wishes.Cardi-O-fix PFO occluder was used in 180 cases (COF group), Amplatzer PFO occluder was used in the remaining 66 cases (Amp group). Post-procedure safety including recurrent stroke, transient ischemic attack, death, and complete closure rate, and efficacy including procedure related complications of different devices were compared during the 12 months follow-up. Results: (1) Rate of transient ischemic attack was similar between COF group and Amp group at 12 months after procedure(1.1%(2/180) vs. 1.5%(1/66), P=1.000). There was no recurrent stroke and death during the 12 months follow-up period.Complete closure rate was similar between COF group and Amp group at 12 months after the procedure(90.6%(163/180)vs. 86.4%(57/66), P=0.355). (2) Three cases(1.7%) of paroxysmal atrial fibrillation were observed in COF group during the 12 months follow-up period, 1 patient converted spontaneously to sinus rhythm and 2 patients received successful pharmacologic conversion and converted to sinus rhythm. One patient(1.5%)developed paroxysmal atrial fibrillation and was pharmacologically converted to sinus rhythm in the Amp group. There was no significant difference in rate of paroxysmal atrial fibrillation between the two groups(P=1.000). There was no complications such as occluder translocation, erosion, pericardial effusion and puncture site bleeding in the 2 groups during the 12 months follow-up. Conclusion: Efficacy and safety are similar for PFO treatment with Cardi-O-fix PFO occluder or Amplatzer PFO occluder in this patient cohort.


Asunto(s)
Foramen Oval Permeable/terapia , Dispositivo Oclusor Septal , Fibrilación Atrial , Cateterismo Cardíaco , Femenino , Humanos , Masculino , Seguridad , Resultado del Tratamiento
4.
Genet Mol Res ; 15(3)2016 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-27706632

RESUMEN

The relationship between the p38-mitogen-activated protein kinase (p38-MAPK) signal pathway and high glucose-induced hepatic stellate cell (HSC) activation was investigated in this study. Sixty human HSC samples were randomly selected and used in the control (cultured normally), high-glucose (cultured in the presence of high glucose), and blocking (cultured under high-glucose conditions in the presence of the p38-MAPK inhibitor, SB203580) groups. The cells were incubated for 120 h and subsequently analyzed for morphological changes by inverted microscopy and for a-smooth muscle actin (a-SMA) expression (to determine the degree of HSC activation) by the method of streptavidin-biotin complex and western blot. Phospho-p38-MAPK protein expression was analyzed by western blotting. a-SMA and phospho-p38-MAPK expression was significantly upregulated in HSCs cultured under high-glucose conditions, compared to the HSCs cultured normally (P < 0.01). On the other hand, phospho-p38-MAPK and a-SMA protein levels were significantly lower in the blocking group compared to the high-glucose group (P < 0.01). Based on these results, we concluded that high-glucose levels induce HSC activation mediated by phospho-p38-MAPK. Therefore, blocking the p38-MAPK signal pathway could inhibit this effect.


Asunto(s)
Actinas/genética , Glucosa/farmacología , Células Estrelladas Hepáticas/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Actinas/agonistas , Actinas/antagonistas & inhibidores , Actinas/metabolismo , Células Cultivadas , Regulación de la Expresión Génica , Glucosa/metabolismo , Células Estrelladas Hepáticas/citología , Células Estrelladas Hepáticas/metabolismo , Humanos , Imidazoles/farmacología , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
5.
Genet Mol Res ; 15(1)2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26909935

RESUMEN

The long non-coding RNA MALAT-1 plays an important role in cancer prognosis. The present research aimed to elucidate its precise predictive value in various human carcinomas. A quantitative meta-analysis was performed by searching PubMed, Embase, Web of Science, and Cochrane Library (most recently, January 2015) databases, and extracting data from studies that investigated the association between MALAT-1 expression and survival outcomes in patients of various cancers. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated as a measure of generalized effect. This meta-analysis included 1317 cases from 12 datasets. Our investigation revealed that poor overall survival (OS; HR = 2.14, 95% CI = 1.74-2.64) and shortened disease-free, recurrence-free, disease-specific, or progression-free survival (HR = 2.13, 95% CI = 1.22-3.72) can be predicted by high MALAT-1 expression for various cancers. Moreover, elevated MALAT-1 levels significantly correlated with decreased OS in a renal cell carcinoma (RCC) subgroup (HR = 3.43, 95% CI = 1.80-6.53). These results imply that MALAT-1 can be used to predict unfavorable prognoses for several cancers, particularly RCC.


Asunto(s)
Carcinoma/genética , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/genética , Adulto , Anciano , Biomarcadores de Tumor , Carcinoma/diagnóstico , Carcinoma/terapia , Supervivencia sin Enfermedad , Humanos , Persona de Mediana Edad
6.
Zhonghua Nei Ke Za Zhi ; 55(9): 705-9, 2016 Sep 01.
Artículo en Zh | MEDLINE | ID: mdl-27586979

RESUMEN

OBJECTIVE: To determine whether store-operated Ca(2+) entry (SOCE) is involved in chronic hypoxia-induced alteration of intracellular Ca(2+) concentration ([Ca(2+) ]i) and proliferation in pulmonary arterial smooth muscle cells (PASMC). METHODS: Rat PASMCs were cultured and treated in normoxia (21%O2) or hypoxia (4%O2) condition. The proliferation of PASMC was detected by cell counting kit-8 (CCK-8) assay. [Ca(2+) ]i, SOCE and the effects of store-operated Ca(2+) channel (SOCC) inhibitors, SKF96365 and NiCl2, on SOCE in hypoxic PASMCs were tested by InCyte [Ca(2+) ]i measurement system. RESULTS: Hypoxia for 24-60 h augmented PASMC proliferation (1.12±0.09 vs 0.71±0.05, P<0.05) and [Ca(2+) ]i [(214.8 ± 20.4) nmol/L vs (115.2±13.2) nmol/L, P<0.05] in a time-dependent manner with the maximum effect at 60 h. Perfusion of Ca(2+) -free Krebs solution containing nifedipine (5 µmol/L), cyclopiazonic acid (CPA, 10 µmol/L) in PASMCs caused a small transient increase of [Ca(2+) ]i with peak [Ca(2+) ]i (113.3±49.3) nmol/L.Chronic hypoxia (4% O2, 60 h) enhanced [Ca(2+) ]i level with peak value of (193.2±22.7) nmol/L (P<0.05) in PASMC.After restoration of extracellular Ca(2+) , CPA caused marked increase of [Ca(2+) ]i with peak value of (328.0 ±56.7) nmol/L.Chronic hypoxia strengthened CPA-induced increase of [Ca(2+) ]i with peak value of (526.0±33.7) nmol/L (P<0.05) in PASMCs.Either SKF96365 50 µmol/L or NiCl2 500 µmol/L distinctly attenuated CPA-induced enhancement of [Ca(2+) ]i, the peak value of which dropped from (526.0±33.7) nmol/L to (170.4±26.4) nmol/L (P<0.05) or (177.4±45.9) nmol/L (P<0.05) respectively. CONCLUSION: Chronic hypoxia boosts the release of Ca(2+) from sarcoplasmic reticulum and promotes the activity of SOCC and SOCE, leading to [Ca(2+) ]i elevation and proliferation of rat PASMCs.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/metabolismo , Calcio/metabolismo , Hipoxia/metabolismo , Músculo Liso Vascular/metabolismo , Nifedipino/farmacología , Arteria Pulmonar/metabolismo , Animales , Canales de Calcio/efectos de los fármacos , Células Cultivadas , Imidazoles , Masculino , Músculo Liso Vascular/citología , Miocitos del Músculo Liso , Arteria Pulmonar/citología , Ratas
7.
Genet Mol Res ; 12(1): 618-30, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23408449

RESUMEN

Natural resistance-associated macrophage protein 1 and 2 encoding genes (Nramp1 and Nramp2) are related to many diseases. We cloned the cDNA of chicken Nramp1 and Nramp2 genes, characterized their expression and polymorphisms, and investigated the association of some SNPs with resistance to salmonellosis. The Nramp1 cDNA was 1746 bp long and the Nramp2 cDNA was 1938 bp long. These cDNAs are similar to previously reported cDNAs, varying by two and one amino acids, respectively. The chicken Nramp1 gene expressed predominantly in liver, thymus and spleen in both females and males. The Nramp2 gene expressed in almost all tissues, but predominantly in breast muscle, leg muscle, cerebrum, cerebellum, lung, kidney, and heart in both females and males. We identified 45 SNPs and 2 indels in the chicken Nramp1 gene; three of 13 SNPs in the exons were missense mutations (Arg223Gln, Ala273Glu and Arg497Gln). Association analysis indicated that A24101991G is significantly associated with chicken salmonellosis resistance. These results will be useful for functional investigation of chicken Nramp1 and Nramp2 genes.


Asunto(s)
Proteínas de Transporte de Catión/genética , Pollos/genética , Infecciones por Salmonella/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Pollos/microbiología , Clonación Molecular , ADN Complementario/genética , Exones , Femenino , Estudios de Asociación Genética/métodos , Masculino , Datos de Secuencia Molecular , Filogenia , Polimorfismo de Nucleótido Simple , Infecciones por Salmonella/prevención & control , Análisis de Secuencia de ADN
8.
Arch Virol ; 157(8): 1481-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22573187

RESUMEN

The standardization and validation of a one-step, single-tube, accelerated fluorescent-intercalating-dye-based reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay targeting the NS3 gene of Japanese B encephalitis virus (JEV) is described for rapid, simple, and high-throughput detection of JEV. The amplification can be completed in 35 min under isothermal conditions at 63°C by employing a set of six primers targeting the NS3 gene of JEV. The RT-LAMP assay described demonstrated high sensitivity for detecting JEV, with a detection limit in swine samples of 8.13 PFU/ml. The specificity of the selected primer sets was established by cross-reactivity studies with pathogens that exhibit similar clinical signs and testing of samples from healthy animals. The clinical applicability of the RT-LAMP assay was validated using either spiked samples or samples from seasonal outbreaks. The comparative evaluation of the RT-LAMP assay revealed 79.59 % concordance with conventional RT-PCR targeting the E gene of JEV. The RT-LAMP assay reported here is a valuable tool for rapid real-time and high-throughput seasonal infection surveillance and quarantine after outbreak through blood sampling by using ordinary real-time PCR thermocyclers without purchasing an expensive Loopamp real-time turbidimeter.


Asunto(s)
Brotes de Enfermedades/veterinaria , Virus de la Encefalitis Japonesa (Especie)/genética , Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Encefalitis Japonesa/veterinaria , Técnicas de Amplificación de Ácido Nucleico/métodos , Enfermedades de los Porcinos/diagnóstico , Proteínas no Estructurales Virales/genética , Animales , China/epidemiología , Cartilla de ADN , Encefalitis Japonesa/diagnóstico , Encefalitis Japonesa/epidemiología , Encefalitis Japonesa/virología , Colorantes Fluorescentes , Técnicas de Diagnóstico Molecular/métodos , ARN Helicasas/genética , Sensibilidad y Especificidad , Serina Endopeptidasas/genética , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología
10.
Genet Mol Res ; 10(4): 3371-84, 2011 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-22180074

RESUMEN

The dopamine D2 receptor (DRD2) is a crucial mediator for normal physiological processes. We cloned the pig DRD2 gene, investigated its distribution in tissues and identified polymorphisms by RT-PCR, quantitative real-time PCR and direct sequencing. Two Yorkshire pigs from Guangdong Academy of Agricultural Sciences (Guangzhou, China) were selected to clone the gene and investigate its expression; 16 individuals from four pig breeds (Yorkshire, Landrace, small-ear spotted, and Xinchang) were used to scan the variations. The two transcripts (DRD2L and DRD2S), obtained through insertion or deletion of exon 5 and part of 3'UTR, were found to encode 444- and 415-amino acid proteins, respectively. The 574-bp indel in 3'UTR comprises five miRNA targeting sites, based on bioinformatics predictions. The pig DRD2 gene expresses predominantly in the pituitary gland, and then in oviducts and the hypothalamus. Both DRD2L and DRD2S mRNA were detected in cerebrum, cerebellum, hypothalamus, pituitary gland, back muscle, oviduct, uterus, and testis tissues; DRD2L was more abundant than DRD2S. The DRD2 gene is located on chromosome 9 and contains seven exons. Sixty-one different sequences were identified in this gene; among seven in the coding region, only one altered the encoded amino acid. These findings will help us understand the functions of the DRD2 gene in pigs.


Asunto(s)
Cruzamiento , Regulación de la Expresión Génica , Variación Genética , Receptores de Dopamina D2/genética , Sus scrofa/genética , Regiones no Traducidas 3'/genética , Secuencia de Aminoácidos , Animales , Emparejamiento Base/genética , Secuencia de Bases , Sitios de Unión , China , Clonación Molecular , ADN Complementario/genética , Femenino , Perfilación de la Expresión Génica , Genoma/genética , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Especificidad de Órganos/genética , Polimorfismo de Nucleótido Simple/genética , Unión Proteica/genética , Receptores de Dopamina D2/química , Eliminación de Secuencia/genética
11.
Science ; 244(4909): 1195-8, 1989 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-2727704

RESUMEN

The three-dimensional structure of human serum albumin has been solved at 6.0 angstrom (A) resolution by the method of multiple isomorphous replacement. Crystals were grown from solutions of polyethylene glycol in the infrequently observed space group P42(1)2 (unit cell constants a = b = 186.5 +/- 0.5 A and c = 81.0 +/- 0.5 A) and diffracted x-rays to lattice d-spacings of less than 2.9 A. The electron density maps are of high quality and revealed the structure as a predominantly alpha-helical globin protein in which the course of the polypeptide can be traced. The binding loci of several organic compounds have been determined.


Asunto(s)
Modelos Moleculares , Albúmina Sérica , Humanos , Polietilenglicoles , Conformación Proteica , Difracción de Rayos X
12.
Cancer Res ; 51(13): 3339-44, 1991 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-2054774

RESUMEN

Four synthetic peptides from the sequence of human O6-methylguanine-DNA methyltransferase (MGMT), three corresponding to different hydrophilic regions and one corresponding to the sequence containing the alkyl acceptor residue cysteine 145, were used to immunize rabbits. The antibody against Peptide III (residues 171-184) was highly specific, and MGMT protein could be detected on Western blots of soluble protein extracts containing as little as 1 fmol of active MGMT. Antibodies against all of the peptides were able to immunoprecipitate denatured MGMT, while only the antibody against Peptide III was able to react with active enzyme. The antibody against Peptide III did not cross-react with methyltransferase from mice. The use of synthetic peptides has led to the production of a highly sensitive, specific antibody that recognizes native and denatured human MGMT. This antibody should prove useful in studies involving the detection, purification, and characterization of this enzyme.


Asunto(s)
Anticuerpos/inmunología , Metiltransferasas/inmunología , Secuencia de Aminoácidos , Especificidad de Anticuerpos , Western Blotting , Humanos , Metiltransferasas/química , Datos de Secuencia Molecular , O(6)-Metilguanina-ADN Metiltransferasa , Péptidos/síntesis química , Péptidos/inmunología , Pruebas de Precipitina , Solubilidad , Especificidad de la Especie
13.
Cancer Res ; 52(5): 1144-8, 1992 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-1737373

RESUMEN

Six well characterized human medulloblastoma cell lines (D283 Med, Daoy, D341 Med, D384 Med, D425 Med, and D458 Med) were examined for the expression of O6-methylguanine-DNA methyltransferase (MGMT) by activity and Western and Northern blot analysis. High levels of MGMT activity were present in D283 Med, Daoy, D341 Med, and D384 Med (1.36, 0.80, 1.68, and 1.62 pmol/mg of protein, respectively), but negligible MGMT activity was detected in D425 Med and D458 Med (0.06 and 0.05 pmol/mg of protein, respectively), which were derived separately at different times from the same patient. The presence of MGMT protein and its transcript was demonstrated in D283 Med, Daoy, D341 Med, and D384 Med, but both the protein and the mRNA were undetectable in D425 Med and D458 Med. Nevertheless, all six cell lines contained an apparently unaltered MGMT gene, as determined by Southern blot analysis. The absence of MGMT activity in D425 Med and D458 Med is likely due to the absence of the protein, resulting from a lack of transcription of the MGMT gene. The varying levels of expression of MGMT in medulloblastoma cells found in this study should provide a molecular basis for drug design and selection in chemotherapy of this tumor.


Asunto(s)
Meduloblastoma/enzimología , Metiltransferasas/metabolismo , ARN Mensajero/metabolismo , Northern Blotting , Western Blotting , Humanos , O(6)-Metilguanina-ADN Metiltransferasa , Células Tumorales Cultivadas
14.
J Mol Biol ; 216(3): 511-2, 1990 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-2258926

RESUMEN

A monoclonal IgG antibody directed against gp 41 from the human immunodeficiency virus (HIV-1) has been crystallized in both intact and Fab forms. Crystals of the intact antibody grow as tetragonal-like prisms too small for conventional X-ray analysis. However, the Fab portion of the antibody produces suitable plate-like crystals which belong to the space group P2(1)2(1)2(1) with unit cell constants of a = 66.5 A, b = 74.3 A and c = 105.3 A. There is one molecule of Fab in the asymmetric unit. The Fab crystals show diffraction to d-spacings less than 3.0 A.


Asunto(s)
Proteína gp41 de Envoltorio del VIH/inmunología , VIH-1/inmunología , Anticuerpos Monoclonales/química , Reacciones Antígeno-Anticuerpo , Cristalización , Fragmentos Fab de Inmunoglobulinas/química , Difracción de Rayos X
15.
J Mol Biol ; 228(1): 188-207, 1992 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-1447781

RESUMEN

An IgM(kappa) immunoglobulin from a patient (Pot) with Waldenstrom's macroglobulinemia was hydrolyzed with pepsin to release a fragment consisting of the 'variable' (V) domains of the light and heavy chains plus eight residue 'tails' from the 'constant' (C) domains. The crystal structure of this fragment was determined at 2.3 A resolution by molecular replacement and crystallographic refinement methods. When examined separately, the light chain component closely resembles another human kappa chain (Rei) in both the beta-pleated sheet regions and the 'hypervariable' loops. The conserved pleated sheets in the heavy chain are similar to those in the human Kol IgG1 protein, but the third hypervariable loop in particular is different from that in any immunoglobulin structure described to date. As in the Kol protein, this loop blocks the access to any internal active site along the light-heavy chain interface. Unlike the Kol protein, however, the loop does not protrude beyond the boundaries of a conventional antigen combining site. Instead, it forms a very compact structure, which fills almost all residual space between the domains. This is an example of one dominant complementarity-determining region (CDR) essentially negating the diversity possible with five other CDRs in the two chains. Ordered water molecules are associated with light chain constituents along the interface, but not with CDR3 of the heavy chain. In screening exercises the Pot IgM failed to bind a wide variety of peptides. Together, the results suggest that ligand binding can only occur on external surfaces of the protein. These surfaces carry a limited number of side chains usually assigned to CDRs in more typical antibodies.


Asunto(s)
Inmunoglobulina M/química , Región Variable de Inmunoglobulina/química , Secuencia de Aminoácidos , Sitios de Unión , Cristalización , Humanos , Cadenas Pesadas de Inmunoglobulina/química , Cadenas Ligeras de Inmunoglobulina/química , Datos de Secuencia Molecular , Conformación Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Solventes , Difracción de Rayos X
16.
Mol Immunol ; 26(3): 207-20, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2495436

RESUMEN

Previous studies showed that the Mcg dimer of immunoglobulin light chains bound bis(dinitrophenyl)lysine both in trigonal crystals and in solution. On prolonged storage in ammonium sulfate, mixtures of ligand and protein produced small trigonal cocrystals in low frequency. These crystals were nearly isomorphous with those of the unliganded dimer in which the subunits were covalently linked by an interchain disulfide bond. By difference Fourier analyses at 3.5 A resolution and subsequent crystallographic refinement, the cocrystals were found to contain molecules with two ligands aligned in tandem along the interface of the variable (V) domains of the protein. One ligand molecule adopted an almost fully extended conformation, with the epsilon-DNP ring situated near the floor, the alpha-carboxyl group directed toward the solvent at the entry, and the alpha-DNP ring outside the rim of the main cavity. As if architecturally designed, the ligand was located symmetrically between the two domains in an orientation that was compatible with both the unaltered structure of the cavity lining and with the known crystal packing interactions of neighboring protein molecules. The second ligand molecule in the cocrystal lodged in the deep pocket immediately under the floor of the main cavity. The ligand adopted a very compact conformation with the two DNP rings roughly antiparallel to each other. This molecule appeared to be semi-permanently sequestered in the pocket since it could not be dislodged by exhaustive perfusion with ammonium sulfate crystallizing media. Relative to its volume in the native dimer, the pocket was expanded to accommodate the oversized ligand. Within a single protein molecule, therefore, two types of binding of a flexible ligand were observed, one with and one without accompanying conformational changes in the protein. The number of cocrystals which could be produced was markedly increased if the interchain disulfide bond between the Mcg monomers was first reduced and alkylated.


Asunto(s)
Proteína de Bence Jones/metabolismo , Cadenas Ligeras de Inmunoglobulina , Lisina/análogos & derivados , Sulfato de Amonio/metabolismo , Animales , Sitios de Unión , Cristalización , Haptenos/metabolismo , Ligandos , Lisina/metabolismo , Sustancias Macromoleculares , Modelos Moleculares , Conformación Proteica
17.
Mol Immunol ; 24(3): 267-74, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3112562

RESUMEN

A method is described for the hybridization of immunoglobulin light chains (Bence-Jones proteins) from different patients. The interchain half-cystine residues in the light chains from one subject are converted into mixed disulfides with 2,2'-dithiodipyridine. In the Bence-Jones dimer from a second patient the interchain disulfide bond is reduced with dithiothreitol. A covalently linked hybrid molecule is produced by the reaction of the mixed disulfide with the reduced thiol. In favorable cases the mild treatment yields heterodimers which can be crystallized for X-ray diffraction studies. The procedure can also be employed for converting a monomer into a covalent dimer. The engineered dimer of one kappa chain (Jen) crystallizes in the same space group as an aggregate of monomers, but the unit cell is only one-third as large.


Asunto(s)
Disulfuros , Cadenas Ligeras de Inmunoglobulina , Proteína de Bence Jones , Fenómenos Químicos , Química , Cristalización , Electroforesis en Acetato de Celulosa , Electroforesis en Gel de Poliacrilamida , Piridinas , Compuestos de Sulfhidrilo
18.
J Cancer Res Ther ; 11 Suppl 1: C89-94, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26323933

RESUMEN

OBJECTIVE: To analyze the clinicopathological features of invasive lobular carcinoma (ILC) and compare them with invasive ductal carcinoma (IDC), hoping to find the fact of ILC in China and assist the decision makers with proper individualized treatment. MATERIALS AND METHODS: A nationwide multicenter retrospective study was performed. A total of 4211 primary breast cancer cases were randomly selected from 1999 to 2008 in seven regions of China. ILC cases were compared with IDC by clinicopathological features and molecular subtypes. RESULTS: A total of 135 (3.2%) ILC and 3471 (82.4%) IDC cases were included for analysis. The age, tumor size, menopausal state, family history, nodal status, and stage of ILC were similar to that of IDC. ILC was more likely to be positive for estrogen receptor (65.5% vs. 57.7%) and progesterone receptor (64.7% vs. 58.5%), and less likely to overexpress human epidermal growth factor receptor-2 (17.3% vs. 23.6%). Even though, these differences are not significant, the proportion of luminal A type of ILC is significantly larger than that of IDC (54.8% vs. 42.7%; P < 0.05). CONCLUSION: ILC has a larger proportion of luminal A type compared with IDC. Larger sample size study for better known of molecular subtypes of ILC is needed in future to individualize the treatment decision.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Carcinoma Lobular/epidemiología , Carcinoma Lobular/patología , Adulto , Biomarcadores , Neoplasias de la Mama/metabolismo , Carcinoma Lobular/metabolismo , China/epidemiología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Factores de Riesgo
19.
J Neuropathol Exp Neurol ; 50(6): 756-69, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1748882

RESUMEN

Monoclonal antibodies (MAb; DMAb, monoclonal antibodies derived at Duke Medical Center) directed against the oncofetally expressed lactotetraosyl gangliosides 3'-isoLM1 (IV3NeuAc-LcOse4Cer) and 3',6'-isoLD1 (IV3NeuAc,III6NeuAc-LcOse4Cer) were produced and their reactivity spectra compared to that of the alpha-3'-isoLM1 MAb SL-50. The IgM MAb SL-50 defines the epitope NeuAc (or NeuGc)alpha 2-3Gal beta 1-3GlcNAc, the terminal sequence of both gangliosides. SL-50 requires an unsubstituted GlcNAc residue; IgM DMAb-14 will accept the alpha 2-6 linked sialic acid to GlcNAc found in 3',6'-isoLD1. Immunohistochemical localization of 3'-isoLM1 was performed on 31 biopsy specimens of human gliomas; 15 (48%) expressed 3'-isoLM1 as defined by binding of MAb SL-50. Staining of small anaplastic cells, giant cells, and the glial component of gliosarcomas was observed. Neoplastic gemistocytes, when present, showed particularly intense staining. The 3'-isoLM1 and 3',6'-isoLD1 distribution in cultured cell lines and derived xenografts of primary tumors of the human central nervous system and of embryonal or neuroectodermal tumor derivation was determined. Six of 29 cell lines expressed 3'-isoLM1: 2/16 gliomas, 3/3 teratomas, 1/1 pancreatic adenocarcinoma. No cell line expressed detectable 3',6'-isoLD1 by immunostain analysis of ganglioside extracts. The 3'-iso-LM1-positive cell lines expressed it in xenograft form; in five xenografts, the corresponding cell lines of which were 3'-isoLM1-negative, it was a proportion of the monosialoganglioside fraction. 3',6'-isoLD1 was detected in two xenografts, D-54 MG (glioma) and PA-1 (teratoma). The demonstration of 3'-isoLM1 in gliomas in in vivo forms and the relatively infrequent expression by derived cultured cells suggest that ganglioside expression is modified by environmental forces. Expression of 3'-isoLM1 and 3',6'-isoLD1 in fetal and neonatal brain, in intense reactive astrocytosis such as polyunsaturated fatty acid lipidosis, and in primary neoplasms of the central nervous system suggests their role in cell-cell attachment during development, migration, and neoplastic transformation.


Asunto(s)
Anticuerpos Monoclonales , Neoplasias Encefálicas/química , Gangliósidos/análisis , Glioma/química , Animales , Humanos , Técnicas In Vitro , Masculino , Meduloblastoma/química , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neuroblastoma/química , Teratoma/química , Neoplasias Testiculares/química , Células Tumorales Cultivadas
20.
J Neuropathol Exp Neurol ; 48(1): 48-68, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2535715

RESUMEN

An extensive panel of monoclonal antibodies (MAb) and monospecific antisera reactive against neuroectodermal-, neuronal-, glial-, and lymphoid-associated antigens, extracellular matrix, HLA, and cell-surface receptors was used to characterize the phenotype of four continuous, karyotypically distinct medulloblastoma cell lines and transplantable xenografts. All four cell lines demonstrated significant reactivity with anti-neuroectodermal-associated MAb. No apparent pattern of reactivity with anti-lymphoid MAb was seen; notably, there was a uniform absence of detectable Thy-1. Review of the complete antibody reactivity profile revealed a dichotomy between lines TE-671 and Daoy and lines D283 Med and D341 Med, which have been previously shown to express neurofilament protein in culture and xenografts, and to exhibit neuroblastic morphological features in biopsy and xenograft tissue sections. TE-671 and Daoy reacted with the MAb directed against tenascin, epidermal growth factor (EGF) receptor, HLA-A,B epitopes, beta 2-microglobulin and 5/8 of the glioma-associated antigens, but did not react with the anti-neurofilament protein (NFP) MAb. D283 Med and D341 Med expressed NFP but did not react with MAb against tenascin, EGF receptor, HLA-A,B epitopes, beta 2-microglobulin or 6/8 and 7/8 (respectively) of the glioma-associated antigens. The observed phenotypic differences provide a conceptual framework for investigating basic differences in the biological behavior of medulloblastoma. Moreover, the subdivisions can be evaluated for prospective value in tissue diagnosis, cerebrospinal fluid cytology and antibody-mediated imaging and therapy.


Asunto(s)
Anticuerpos Monoclonales , Meduloblastoma/genética , Trasplante de Neoplasias , Animales , Línea Celular , Ectodermo/inmunología , Matriz Extracelular/inmunología , Femenino , Antígenos HLA/inmunología , Humanos , Sueros Inmunes/inmunología , Técnicas Inmunológicas , Tejido Linfoide/inmunología , Masculino , Meduloblastoma/inmunología , Meduloblastoma/patología , Neuroglía/inmunología , Neuronas/inmunología , Fenotipo , Ratas , Ratas Desnudas , Receptores de Superficie Celular/inmunología , Trasplante Heterólogo
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