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1.
Phys Rev E ; 94(3-1): 033206, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27739720

RESUMO

Radially polarized intense terahertz (THz) radiation behind a thin foil irradiated by ultrahigh-contrast ultrashort relativistic laser pulse is recorded by a single-shot THz time-domain spectroscopy system. As the thickness of the target is reduced from 30 to 2 µm, the duration of the THz emission increases from 5 to over 20 ps and the radiation energy increases dramatically, reaching ∼10.5mJ per pulse, corresponding to a laser-to-THz radiation energy conversion efficiency of 1.7%. The efficient THz emission can be attributed to reflection (deceleration and acceleration) of the laser-driven hot electrons by the target-rear sheath electric field. The experimental results are consistent with that of a simple model as well as particle-in-cell simulation.

2.
Cell Death Dis ; 6: e1716, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25855964

RESUMO

Methylated histone readers are critical for chromatin dynamics, transcription, and DNA repair. Human PHRF1 contains a plant homeodomain (PHD) that recognizes methylated histones and a RING domain, which ubiquitinates substrates. A recent study reveals that PHRF1 is a tumor suppressor that promotes TGF-ß cytostatic signaling through TGIF ubiquitination. Also, PHRF1 is a putative phosphorylation substrate of ataxia telangiectasia-mutated/ataxia telangiectasia and Rad3-related kinases; however, the role of PHRF1 in DNA damage response is unclear. Here we report a novel function of PHRF1 in modulating non-homologous end-joining (NHEJ). PHRF1 quickly localizes to DNA damage lesions upon genotoxic insults. Ablation of PHRF1 decreases the efficiency of plasmid-based end-joining, whereas PHRF1 overexpression leads to an elevated NHEJ in H1299 reporter cells. Immunoprecipitation and peptide pull-down assays verify that PHRF1 constitutively binds to di- and trimethylated histone H3 lysine 36 (H3K36) (H3K36me2 and H3K36me3) via its PHD domain. Substitution of S915DT917E to ADAE in PHRF1 decreases its affinity for NBS1. Both PHD domain and SDTE motif are required for its NHEJ-promoting activity. Furthermore, PHRF1 mediates PARP1 polyubiquitination for proteasomal degradation. These results suggest that PHRF1 may combine with H3K36 methylation and NBS1 to promote NHEJ and stabilize genomic integrity upon DNA damage insults.


Assuntos
Dano ao DNA , Reparo do DNA por Junção de Extremidades , Proteínas de Ligação a DNA/genética , Proteínas do Grupo Polycomb/genética , Sequência de Aminoácidos , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Genoma Humano , Células HEK293 , Histonas/genética , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Metilação , Dados de Sequência Molecular , Proteínas do Grupo Polycomb/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-25215833

RESUMO

It is shown that the transverse Rayleigh-Taylor-like (RT) instability in the hole-boring radiation pressure acceleration can be suppressed by using an elliptically polarized (EP) laser. A moderate J×B heating of the EP laser will thermalize the local electrons, which leads to the transverse diffusion of ions, suppressing the short wavelength perturbations of RT instability. A proper condition of polarization ratio is obtained analytically for the given laser intensity and plasma density. The idea is confirmed by two-dimensional particle-in-cell simulations, showing that the ion beam driven by the EP laser is more concentrated and intense compared with that of the circularly polarized laser.


Assuntos
Íons , Lasers , Modelos Teóricos , Radiação , Simulação por Computador , Difusão , Elétrons , Pressão , Prótons , Temperatura
4.
Genet Mol Res ; 12(3): 3455-64, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-24065684

RESUMO

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is expressed in different tissues and cells, including the pancreas and lymphocytes, and it can selectively induce apoptosis in tumor cells but not in most normal cells. TRAIL plays critical roles in type 1 diabetes mellitus, and is involved in type 2 diabetes mellitus (T2DM). We recently discovered the association of nonalcoholic fatty liver disease, a risk factor for T2DM, with a single nucleotide polymorphism (SNP) in the TRAIL (TNFSF10) gene at site 1595C/T (rs1131580), indicating the possible association of T2DM with this TRAIL polymorphism. The aim of this study was to investigate the relationship of the TRAIL SNP at site 1595C/T (rs1131580) with T2DM susceptibility and the biometabolic parameters of T2DM in a Han Chinese population. The polymerase chain reaction-restriction fragment length polymorphism method was used to genotype SNP rs1131580 in 292 patients with T2DM and 266 healthy controls. We found that the frequency of the CC genotype and that of the C allele of rs1131580 were significantly higher in T2DM patients than in the control group. Additionally, the triglyceride and serum creatinine levels of T2DM patients with the CC genotype were significantly higher than those of patients with the TT genotype. Thus, the CC genotype of the TRAIL SNP at 1595C/T (rs1131580) confers increased susceptible to T2DM in a Han Chinese population from Shandong Province. These data suggest that the CC genotype at this SNP is related to diabetic severity and it might be a candidate for the prognostic assessment of T2DM.


Assuntos
Diabetes Mellitus Tipo 2/genética , Estudos de Associação Genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Diabetes Mellitus Tipo 2/patologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico
5.
Int J Cancer ; 130(5): 1036-45, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21400511

RESUMO

MicroRNAs (miRNAs) regulate mRNA stability and protein expression, and certain miRNAs have been demonstrated to act either as oncogenes or tumor suppressors. Differential miRNA expression signatures have been documented in many human cancers but the role of miRNAs in endometrioid endometrial cancer (EEC) remains poorly understood. This study identifies significantly dysregulated miRNAs of EEC cells, and characterizes their impact on the malignant phenotype. We studied the expression of 365 human miRNAs using Taqman low density arrays in EECs and normal endometriums. Candidate differentially expressed miRNAs were validated by quantitative real-time PCR. Expression of highly dysregulated miRNAs was examined in vitro through the effect of anti-/pre-miRNA transfection on the malignant phenotype. We identified 16 significantly dysregulated miRNAs in EEC and 7 of these are novel findings with respect to EEC. Antagonizing the function of miR-7, miR-194 and miR-449b, or overexpressing miR-204, repressed migration, invasion and extracellular matrix-adhesion in HEC1A endometrial cancer cells. FOXC1 was determined as a target gene of miR-204, and two binding sites in the 3'-untranslated region were validated by dual luciferase reporter assay. FOXC1 expression was inversely related to miR-204 expression in EEC. Functional analysis revealed the involvement of FOXC1 in migration and invasion of HEC1A cells. Our results present dysfunctional miRNAs in endometrial cancer and identify a crucial role for miR-204-FOXC1 interaction in endometrial cancer progression. This miRNA signature offers a potential biomarker for predicting EEC outcomes, and targeting of these cancer progression- and metastasis-related miRNAs offers a novel potential therapeutic strategy for the disease.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Invasividade Neoplásica , Regiões 3' não Traduzidas , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Neoplasias do Endométrio , Endométrio/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Transfecção , Estudos de Validação como Assunto
6.
Gynecol Obstet Invest ; 72(3): 203-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21860208

RESUMO

BACKGROUND: The CHD5 gene located on 1p36 encodes a protein-chromodomain helicase DNA-binding protein 5. CHD5 has been shown to be a tumor suppressor gene candidate. This study investigated the involvement of CHD5 in ovarian cancer and its clinicopathological significance. METHODS: CHD5 expression in ovarian cancer and its counterpart were determined by quantitative RT-PCR. The correlation of CHD5 expression to clinicopathological features of the tumor was analyzed. RESULTS: CHD5 expression was downregulated by at least twofold in 32 of 72 (41%) invasive epithelial ovarian carcinomas when compared to 12 controls in Hong Kong Chinese women. CHD5 downregulation was correlated to clinical status (p < 0.05), but not to patient age, tumor type and grade, recurrence and clinical stage (p > 0.05). Survival analysis showed that patients with CHD5 downregulation in their tumors were associated with shorter disease-free and total survival times compared to those without CHD5 downregulation (p < 0.05). Cox proportional-hazards regression analysis indicated that downregulation of CHD5 is an independent adverse prognostic factor in ovarian cancer. CONCLUSION: This study shows that CHD5 is downregulated in a certain number of ovarian cancers and appears to be an adverse predictor candidate of ovarian cancer disease-free and total survival.


Assuntos
DNA Helicases/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Epiteliais e Glandulares/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/genética , Carcinoma Epitelial do Ovário , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida
7.
Phys Rev Lett ; 107(26): 265003, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22243162

RESUMO

Near-infrared radiation around 1000 nm generated from the interaction of a high-density MeV electron beam, obtained by impinging an intense ultrashort laser pulse on a solid target, with a metal grating is observed experimentally. Theoretical modeling and particle-in-cell simulation suggest that the radiation is caused by the Smith-Purcell mechanism. The results here indicate that tunable terahertz radiation with tens GV/m field strength can be achieved by using appropriate grating parameters.

8.
Oncogene ; 26(13): 1971-82, 2007 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-17043662

RESUMO

Endometrial cancer is the third most common gynecologic malignancy and the ninth most common malignancy for females overall in Hong Kong. Approximately 80% or more of these cancers are endometrioid endometrial adenocarcinomas. The aim of this study was to reveal genes contributing to the development of endometrioid endometrial cancer, which may impact diagnosis, prognosis and treatment of the disease. Whole-genome gene expression analysis was completed for a set of 55 microdissected sporadic endometrioid endometrial adenocarcinomas and 29 microdissected normal endometrium specimens using the Affymetrix Human U133 Plus 2.0 oligonucleotide microarray. Selected genes of interest were validated by quantitative real-time-polymerase chain reaction (qRT-PCR). Pathway analysis was performed to reveal gene interactions involved in endometrial tumorigenesis. Unsupervised hierarchical clustering displayed a distinct separation between the endometrioid adenocarcinomas and normal endometrium samples. Supervised analysis identified 117 highly differentially regulated genes (>or=4.0-fold change), which distinguished the endometrial cancer specimens from normal endometrium. Twelve novel genes including DKK4, ZIC1, KIF1A, SAA2, LOC16378, ALPP2, CCL20, CXCL5, BST2, OLFM1, KLRC1 and MBC45780 were deregulated in the endometrial cancer, and further validated in an independent set of 56 cancer and 29 normal samples using qRT-PCR. In addition, 10 genes were differentially regulated in late-stage cancer, as compared to early-stage disease, and may be involved in tumor progression. Pathway analysis of the expression data from this tumor revealed an interconnected network consisting of 21 aberrantly regulated genes involved in angiogenesis, cell proliferation and chromosomal instability. The results of this study highlight the molecular features of endometrioid endometrial cancer and provide insight into the events underlying the development and progression of endometrioid endometrial cancer.


Assuntos
Neoplasias do Endométrio/metabolismo , Perfilação da Expressão Gênica , Genoma , Transdução de Sinais , Neoplasias do Endométrio/genética , Feminino , Hong Kong , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Int J Gynecol Cancer ; 14(5): 921-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15361204

RESUMO

Patients diagnosed to have endometrial carcinoma without prior hysteroscopic examination were recruited from March 2000 to August 2003. Normal saline was used to distend the uterine cavity during the hysteroscopic examination to look for endocervical spread before the definitive surgical treatment. We performed laparotomy, clamped both fallopian tubes, and collected peritoneal washing before the hysteroscopic examination was performed. Peritoneal washing was collected once more after the hysteroscopic examination. Hysteroscopic assessment was performed in 103 patients. Of them, 10 patients were excluded from the study due to previous history of tubal sterilization or blockage. The final analysis was confined to 93 patients. Positive peritoneal cytology was found in 10 (10.8%) patients and this finding was significantly related to the tumor grading (P = 0.023), adnexal involvement (P = 0.003), cervical invasion (P = 0.01), and the presence of peritoneal seedlings (P = 0.001). In five of the 10 patients with positive peritoneal cytology before the hysteroscopic examination, malignant cells could also be recovered in the peritoneal washing collected after the hysteroscopic examination. For patients with negative peritoneal cytology before hysteroscopy, none exhibited positive peritoneal cytology after the procedure. Our data suggested that complete occlusion of both fallopian tubes can effectively prevent the dissemination of endometrial malignant cells into the peritoneal cavity during hysteroscopy.


Assuntos
Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Histeroscopia/efeitos adversos , Histeroscopia/métodos , Metástase Neoplásica/prevenção & controle , Neoplasias Peritoneais/prevenção & controle , Neoplasias Peritoneais/secundário , Adulto , Idoso , Tubas Uterinas , Feminino , Humanos , Laparotomia , Pessoa de Meia-Idade , Lavagem Peritoneal , Estudos Prospectivos , Cloreto de Sódio/administração & dosagem
10.
Gynecol Oncol ; 92(3): 784-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14984941

RESUMO

OBJECTIVE: To evaluate the use of laparoscopic ultrasound (USG) to detect pelvic nodal metastasis in patients with early stage cervical carcinoma. METHODS: Laparoscopic USG was used to search for pelvic lymph node metastasis in stage Ia2 to IIa cervical carcinoma patients before radical hysterectomy. Suspicious lymph nodes identified by laparoscopic USG were removed laparoscopically for pathological confirmation by frozen section. If nodal metastasis was diagnosed, radical hysterectomy would be cancelled but enlarged lymph nodes were removed preferably by laparoscopic approach before closing the abdomen. These patients were treated with radiotherapy after recovering from the surgery. By comparing the laparoscopic USG and pathological findings of lymph nodes removed with or without radical hysterectomy, diagnostic accuracy of laparoscopic USG was determined. RESULTS: Ninety-three patients were recruited and the final analysis included 90 patients. Laparoscopic USG found suspicious lymph nodes in 17 patients and nodal metastases were confirmed pathologically in 14 of them. Three patients with macroscopic and five patients with microscopic pelvic nodal metastases were missed by laparoscopic USG. The accuracy, sensitivity, specificity, positive and negative predictive value of laparoscopic USG in detecting pelvic lymph node metastasis were 87.8%, 63.6%, 95.6%, 82.4%, and 89%, respectively. Macroscopic metastatic nodes were successfully removed laparoscopically in 11 out of 14 patients and laparotomy was required for the other three patients. CONCLUSIONS: Laparoscopic USG can be performed with no major morbidity. This technique is sensitive in detecting macroscopic but not microscopic metastatic pelvic lymph nodes. Removal of macroscopic metastatic nodes identified via laparoscopic USG via laparoscopic approach could be accomplished in majority of patients.


Assuntos
Linfonodos/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Histerectomia , Laparoscopia/métodos , Excisão de Linfonodo/métodos , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pelve , Ultrassonografia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
12.
Int J Gynecol Cancer ; 13(6): 863-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14675325

RESUMO

The case histories of 95 patients with endometrial carcinoma treated between July 1998 and December 2002 were reviewed. These patients were staged according to FIGO classification and included peritoneal cytology, total abdominal hysterectomy/bilateral salpingo-oophorectomy (TAHBSO), and pelvic with or without para-aortic lymphadenectomy. The FIGO surgical stages were as follow: IA, 9 (9.5%); IB, 35 (36.8%); IC, 16 (16.8%); IIB, 10 (10.5%); IIIA, 5 (5.3%); IIIB, 1 (1.1%); IIIC, 19 (20.0%). In addition to TAHBSO, 47 (49.5%) patients had pelvic lymphadenectomy whereas 48 (50.5%) had both pelvic and para-aortic lymphadenectomy. Nineteen (20.0%) of 95 patients had nodal metastases. Positive pelvic and para-aortic lymph nodes were found in 15 (15.8%) of 95 and 12 (25.0%) of 48 patients, respectively. According to the result of the lymphadenectomy, 19 (20.0%) patients had their surgical stage upgraded to stage IIIC and 61 (64.2%) patients had a change in their management plan. Twelve (12.6%) patients required extended field irradiation due to para-aortic nodal metastases and 49 (51.6%) patients with negative nodes avoided postoperative external radiotherapy. By defining the lymphatic spread via surgical staging, postoperative radiotherapy can be recommended to patients with nodal metastases, while it can be withheld from those patients with negative nodes, irrespective of the presence of risk factors.


Assuntos
Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Excisão de Linfonodo , Metástase Linfática , Estadiamento de Neoplasias , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta , Neoplasias do Endométrio/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Pelve , Radioterapia Adjuvante , Estudos Retrospectivos , Resultado do Tratamento
13.
Cancer Lett ; 180(1): 63-8, 2002 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-11911971

RESUMO

Insufficient apoptosis is implicated in many human cancers, including cervical carcinoma. The objectives of this study were to explore changes of apoptosis-regulating gene expression and their clinical significance in cervical cancer. The expression of apoptosis-regulating genes, including five Bcl-2 family and two caspase family members, was evaluated in 43 cervical invasive squamous cell carcinomas, using immunohistochemistry. Specimens in which >or=10% of the neoplastic cells showed cytosolic immunoreactivity were considered to be immunopositive. Results were correlated with clinico-pathologic characteristics of the subjects. All seven apoptotic regulators examined were positive in a proportion of the tumors. The percentage of cases expressing Bax was higher in the patients without evidence of disease after treatment than in the patients alive with disease or who died of disease (P<0.05). A significant difference in disease-free survival was detected between Bax-positive and -negative groups (P<0.05), and in overall survival between Mcl-1-positive and -negative groups (P<0.05). Significant association between the seven markers tested was only found for caspase 3 and Bak immunoreactivity in cervical carcinoma (P<0.05). The results demonstrate expression of multiple apoptosis-modulating proteins in cervical cancer. There appears to be complex regulation of apoptosis protein levels in association with clinical behavior of cervical squamous cell carcinoma.


Assuntos
Apoptose , Proteínas de Neoplasias/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Carcinoma de Células Escamosas/metabolismo , Caspase 3 , Caspases/metabolismo , Sobrevivência Celular , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fatores de Tempo , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteína X Associada a bcl-2
14.
Gynecol Obstet Invest ; 52(2): 98-103, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11586036

RESUMO

Infection with specific genotypes of human papillomavirus (HPV) has been strongly implicated in cervical carcinogenesis. However, HPV infection alone is insufficient for malignant transformation of the cervical epithelium. An alteration of microsatellite repeats is the result of slippage owing to strand misalignment during DNA replication and is referred to as microsatellite instability (MSI). These defects in DNA repair pathways have been related to human carcinogenesis; however, the role of MSI in the tumorigenesis of cervical cancer remains unclear. The clinical and pathological features of cervical cancers which are MSI-positive have also not been fully characterized. This study investigated the prevalence of MSI in cervical cancer and its relationship to clinico-pathological characteristics and HPV infection. Polymerase chain reaction-based microsatellite assay combined with tissue microdissection was used to examine for MSI in 50 cervical squamous cell carcinomas in Hong Kong women. In addition, the immunohistochemical staining was performed to determine the expression of major DNA mismatch repair genes, hMSH2 and hMLH1. Six cases (12%) displayed a low frequency of MSI (MSL-L) showing MSI at one locus only in 5 loci examined. Seven cases (14%) showed a high frequency of MSI (MSI-H) having MSI at 2 or more loci. Grouping MSI-L and MSI-H cases together as MSI-positive, statistical analysis of HPV infection, tumor grade, clinical stage and clinical status failed to disclose differences between MSI-positive and MSI-negative cases (p > 0.05). However, MSI-H correlated with advanced stage of disease (p < 0.05). Individuals with MSI-H tumors appeared to have reduced overall survival compared to individuals with MSI-L and MSI-negative tumors, but the difference was not statistically significant (p = 0.059). An absence of either MSH2 or MLH1 expression was observed in 2 MSI-L and 4 MSI-H cases, respectively. The results suggest that MSI is present in a subgroup of cervical squamous cell carcinomas, and defects resulting in MSI may be related to tumor progression and possibly poor prognosis in cervical cancer.


Assuntos
Pareamento Incorreto de Bases/genética , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/genética , Proteínas de Ligação a DNA , Repetições de Microssatélites/genética , Proteínas de Neoplasias/genética , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Proteínas Proto-Oncogênicas/genética , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/genética , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/genética , Proteínas Adaptadoras de Transdução de Sinal , Carcinoma de Células Escamosas/patologia , Proteínas de Transporte , Feminino , Humanos , Imuno-Histoquímica , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Estadiamento de Neoplasias , Proteínas Nucleares , Infecções por Papillomavirus/patologia , Inclusão em Parafina , Reação em Cadeia da Polimerase , Análise de Sobrevida , Infecções Tumorais por Vírus/patologia , Neoplasias do Colo do Útero/patologia
15.
J Clin Pathol ; 54(5): 401-3, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11328843

RESUMO

AIM: To evaluate the efficiency of phenol/chloroform, microwave, and Qiagen spin column based DNA extractions from paraffin wax embedded tissue for use in the polymerase chain reaction (PCR). In addition, to assess the reliability of amplifying a housekeeping gene to indicate successful viral DNA extraction. METHODS: DNA samples extracted from 20 blocks of cervical carcinoma tissues using the three methods were subjected to PCRs targeting 509 bp and 355 bp of the beta globin gene, and 450 bp and 150 bp of human papillomavirus (HPV) DNA. RESULTS: Microwave extraction showed the highest positive rate for beta globin PCR, whereas the spin column method was the most efficient for HPV DNA extraction. When the 509 bp beta globin and 450 bp HPV PCR results were correlated, two of 10, eight of 12, and nine of 10 beta globin positive extractions prepared by means of the phenol/chloroform, microwave, and spin column methods, respectively, yielded HPV DNA of the expected size. For the beta globin negative samples, HPV was detected in three of 10, two of eight, and four of 10 samples. CONCLUSIONS: HPV DNA extraction was most efficient using the Qiagen spin column and had the highest positive predictive value when a housekeeping gene was used as an indicator of successful viral DNA extraction; the phenol/chloroform method was the least efficient. The potential drawbacks of some extraction methods when using a human housekeeping gene to assess the quality of viral DNA extraction need to be considered.


Assuntos
Carcinoma de Células Escamosas/virologia , DNA de Neoplasias/isolamento & purificação , DNA Viral/isolamento & purificação , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/virologia , Carcinoma de Células Escamosas/genética , Clorofórmio , Feminino , Globinas/genética , Humanos , Micro-Ondas , Papillomaviridae/classificação , Inclusão em Parafina , Fenol , Neoplasias do Colo do Útero/genética
17.
AJR Am J Roentgenol ; 175(3): 759-66, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10954463

RESUMO

OBJECTIVE: This study compares dynamic helical CT with dynamic MR imaging in the evaluation of pelvic lymph nodes in cervical carcinoma. SUBJECTS AND METHODS: Women with biopsy-proven cervical carcinoma prospectively underwent dynamic helical CT and MR imaging before surgery. A metastatic node on CT and MR imaging was defined as a rounded soft-tissue structure greater than 10 mm in maximal axial diameter or a node with central necrosis. Imaging results were compared with pathology, and receiver operating characteristic curves for size and shape were plotted on a hemipelvis basis. Nodal density and signal intensity on CT and MR images, respectively, were reviewed for differences between benign and malignant disease. RESULTS: A total of 949 lymph nodes were found at pathology in 76 hemipelves in 43 women, of which 69 lymph nodes (7%) in 17 hemipelves (22%) were metastatic. Sensitivity, specificity, positive and negative predictive values, and accuracy of helical CT and MR imaging in the diagnosis of lymph node metastasis on a hemipelvis basis was 64.7%, 96.6%, 84.6%, 90.5%, and 89.5% and 70.6%, 89.8%, 66. 7%, 91.4%, and 85.5%, respectively. Receiver operating characteristic curves for helical CT and MR imaging gave cutoff values of 9 and 12 mm in maximal axial diameter, respectively, in the prediction of metastasis. Central necrosis had a positive predictive value of 100% in the diagnosis of metastasis. Signal intensity on MR imaging and density-enhancement pattern on CT in patients with metastatic nodes did not differ from those in patients with negative nodes. CONCLUSION: Helical CT and MR imaging show similar accuracy in the evaluation of pelvic lymph nodes in patients with cervical carcinoma. Central necrosis is useful in the diagnosis of metastasis in pelvic lymph nodes in cervical cancer.


Assuntos
Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Feminino , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pelve , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
18.
Cancer Lett ; 154(2): 189-94, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10806307

RESUMO

Loss of heterozygosity (LOH) is a common genetic finding in many human neoplasms, including cervical cancer. The detection of LOH at specific loci in the precursor of cervical cancer, cervical intraepithelial neoplasia (CIN) may help in elucidating the evolution of this cancer, which has a clearly defined histological premalignant phase. However, molecular genetic investigation of CIN is difficult because many of the lesions are very small and sometimes ill defined topographically. In this study we analyzed eighteen polymorphic microsatellite repeats on chromosome 3p in CINs using a method of primer extension pre-amplification (PEP) for whole genome amplification combined with microdissection. These markers encompass chromosome region 3pter-3p12. LOH at one or more loci was detected in five (33%) out of the 15 informative cases with low grade CIN (CIN 1), while 22 (92%) out of 24 cases with high grade CIN (CIN 2 and 3) (P<0.01). The highest incidence (41%) of LOH was detected at locus D3S1038 (3p26.1-3p25.2). Frequent LOH (more than 20%) was also found at other loci including D3S1110 (3p25.3-3p25.1) (31%), D3S656 (3p25.1) (24%), D3S1076 (3p21.2-3p21.1) (29%), D3S1300 (3p21.1-3p14.2) (24%), D3S1600 (3p14.2-3p14.1) (24%), and D3S1079 (3p13) (25%). The results from this study taken together with others indicate that the genetic alterations on chromosome 3p are common in high grade of CIN and are probably early events in cervical carcinogenesis. Tumor suppressor gene(s) that play a role in cervical neoplasm may be located on the short arm of chromosome 3, likely at or near 3p26.1-25.1, 3p21.2-21.1, and 3p14.2-13.


Assuntos
Cromossomos Humanos Par 3 , Perda de Heterozigosidade , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Alelos , Feminino , Genótipo , Humanos , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase , Neoplasias do Colo do Útero/diagnóstico
19.
AJR Am J Roentgenol ; 172(6): 1521-5, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10350283

RESUMO

OBJECTIVE: This study compared laparoscopic sonography with surgical pathology in the evaluation of pelvic lymph nodes in women with cervical cancer. SUBJECTS AND METHODS: Intraoperative laparoscopic sonography of pelvic lymph nodes was performed in 31 women with biopsy-proven cervical cancer. A lymph node that was rounded (longitudinal-transverse axis ratio of <2) or showed absence of central hilum was defined as positive for metastasis. For comparison, lymph nodes from each hemipelvis were grouped anatomically into paraaortic, common, internal, and external iliac chains during evaluation on laparoscopic sonography and on surgical pathologic examination. RESULTS: Pelvic dissection in 31 women yielded 630 lymph nodes. There were 54 metastatic nodes in 12 women. Laparoscopic sonography revealed 32 (59%) of all pathologically metastatic lymph nodes. Sensitivity on laparoscopic sonography when comparing groups by hemipelves was 93.3% and by anatomic lymph node chains was 76.2%. Metastatic nodes were most commonly located in the common iliac region and were characteristically rounded, hypoechoic, showed absence of central hilum, and occasionally showed central necrosis. Nine (28%) of 32 metastatic lymph nodes revealed by laparoscopic sonography measured 1 cm or less. Six benign nodes in four patients were also visualized with laparoscopic sonography. CONCLUSION: Laparoscopic sonography achieved a sensitivity exceeding 90% in the detection of metastatic lymph nodes in the hemipelves of women with cervical cancer. Laparoscopic sonography is a feasible and promising technique for the evaluation of pelvic lymph nodes in women with cervical cancer and merits further evaluation.


Assuntos
Endossonografia , Laparoscopia , Linfonodos/diagnóstico por imagem , Pelve/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Meios de Contraste , Endossonografia/instrumentação , Endossonografia/métodos , Endossonografia/estatística & dados numéricos , Feminino , Humanos , Laparoscópios , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Pelve/patologia , Pelve/cirurgia , Sensibilidade e Especificidade , Cloreto de Sódio , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
20.
Am Surg ; 65(5): 406-10, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10231205

RESUMO

Hepatocellular carcinoma (HCC) presenting as obstructive jaundice due to intrabile duct tumor growth is being reported with increasing frequency. We describe our clinical experiences and evaluate the results of different operative procedures for this disease. A retrospective study was undertaken to review 18 patients with obstructive jaundice by tumor emboli from HCC during a 15-year period of time. We reviewed clinical features, types of operative procedures, operative findings, and survival in the patients. All patients on initial examination had recurrent episodic jaundice or cholangitis. Types of surgical procedures were choledochotomy with T-tube drainage alone in nine patients, choledochotomy with T-tube drainage followed by hepatectomy in six, and T-tube drainage followed by transcatheter hepatic arterial chemoembolization in the remaining three patients. Liver cirrhosis was the associated disease in 15 (83.3%). There were three postoperative deaths (16.7%). The mean survival time for nine patients with external drainage alone was 4.5 months. For the three patients with T-tube drainage and transcatheter hepatic arterial chemoembolization, mean survival time was 11 months. Six patients who had undergone hepatectomy had a better postoperative survival time, with 1 surviving for more than 3 years and another alive for 70 months, without evidence of recurrence at the moment. Jaundice is not necessarily a harbinger of advanced disease and a contraindication for surgery. Managed properly, these patients will have satisfactory palliation and occasional cure.


Assuntos
Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Colestase/etiologia , Colestase/cirurgia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Células Neoplásicas Circulantes , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
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