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1.
Zhonghua Fu Chan Ke Za Zhi ; 54(7): 458-463, 2019 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-31365958

RESUMO

Objective: To explore the relationship between cervical lesions and high risk HPV (HR-HPV) viral load reflected by the cycle threshold (Ct) values of Cobas 4800 HPV (Cobas 4800) system. Methods: From August 2016 to September 2017, 7 000 women from Shenzhen, were recruited for cervical cancer screening with Cobas 4800 system and cytology co-test. Colposcope biopsies were performed on women who were positive of HPV 16, 18, and positive of HPV types other than 16,18 with cytology [≥ atypical squamous cell of undetermined signification (ASCUS)], or HPV negative but abnormal of cytology [≥ low grade squamous intraepithelial lesion (LSIL)]. The Ct values of HPV 16, 18 and all combined other types coming from Cobas 4800 system were used as an indicator of viral load to analyze the relationship between type-specific HPV load and the cervical lesions. Results: (1) Among the 7 000 screening women, 370 cases were positive for cervical cancer screening, 325 of them underwent colposcope biopsies, and coloposcopy referred rate was 87.8% (325/370). Among 325 women undergoing cervical biopsy, pathological diagnosis was 119 cases of normal cervical cervix, 151 cases of LSIL, and 55 cases of high-grade squamous intraepithelial lesion (HSIL) and above (HSIL(+); including 53 cases of HSIL, 1 case of cervical adenocarcinoma, and 1 case of cervical squamous cell carcinoma). (2) The Ct value of HPV 16 was inversely correlated with the upgrading of the lesions (r=-0.617, P=0.000), and significant different among normal cervix,LSIL and HSIL(+) (35.4±4.5 vs 31.0±6.0 vs 26.5±4.0; F=25.537, P=0.000). There was no correlation between Ct value of HPV 18 and cervical lesions (r=-0.021, P=0.902). The Ct value of other 12 HPV types was statistically difference among normal normal cervix, HSIL(+) and cervicitis (33.0±5.3 vs 29.9±7.2 vs 29.8±5.8; F=5.087, P=0.007). Among them, LSIL and HSIL(+) were significantly lower than normal cervix (P<0.05), but there was no significant difference between LSIL and HSIL(+) (P>0.05). Conclusion: The Ct value of HPV 16 detecting in Cobas 4800 system as an indicator of virus load obviously correlates with different grades of cervical lesions, therefore could be a reference of cervical lesion existence and an indicator of lesion prognosis.


Assuntos
Neoplasia Intraepitelial Cervical/diagnóstico , Testes de DNA para Papilomavírus Humano/instrumentação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasia Intraepitelial Cervical/patologia , Neoplasia Intraepitelial Cervical/virologia , Detecção Precoce de Câncer , Feminino , Testes de DNA para Papilomavírus Humano/métodos , Humanos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Carga Viral
2.
Zhonghua Fu Chan Ke Za Zhi ; 54(5): 307-311, 2019 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-31154711

RESUMO

Objective: To evaluate the feasibility of the BioPerfectus multiplex real time (BMRT) HPV assay for self-sample cervical cancer screening. Methods: Eight hundreds and thirty-nine self-collected and physician-obtained DNA samples from the Shenzhen cervical cancer screening trial Ⅳ(SHENCCAST-Ⅳ) study collected samples for cervical cancer screening during June 2013 to September 2014 were detected by BMRT HPV assay to evaluate the screening efficacy. Results: A total of the 839 women who were screened, 804 with complete BMRT HPV data was included in the study, and average age was (46±7) years. Of the 804 women, the positive rates of 14 high-risk HPV genotypes (including HPV 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66 subtype) of self-sample and physician-obtained samples were 12.2% (98/804) and 12.8% (103/804), respectively (χ(2)=0.14, P=0.71). Self-collected samples with HPV-positive had significantly more cells (median 19 901.0) than physician-obtained samples (median 1 778.4), and there was statistically significant difference (Z=-7.61, P<0.01). The degree of agreement between self-sample and physician-obtained samples of HPV 16, HPV 18 and other 12 high risk HPV genotype was 99.8%, 100.0% and 96.1%, respectively. And the consistent Kappa value was 0.95, 1.00 and 0.81, respectively. Of 804 samples, there were 6 cervical intraepithelial neoplasia (CIN)Ⅱ(+) cases. There were no missed CINⅡ(+) cases by BMRT HPV assay. Conclusion: BMRT HPV assay is feasible for self-sample cervical cancer screening.


Assuntos
Neoplasia Intraepitelial Cervical/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Autoexame/métodos , Manejo de Espécimes/métodos , Neoplasias do Colo do Útero/diagnóstico , Virologia/métodos , Adolescente , Adulto , Idoso , Neoplasia Intraepitelial Cervical/virologia , DNA Viral , Detecção Precoce de Câncer , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Sensibilidade e Especificidade , Esfregaço Vaginal , Adulto Jovem
3.
Mol Biotechnol ; 61(5): 355-364, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30637606

RESUMO

N6-methyladenosine (m6A) is the most abundant-internal modification of eukaryotic mRNA. m6A can be installed and removed by specific enzymes. The "writer," "eraser," and "reader" of m6A modification have been reported. These discoveries facilitate our understanding of the functional significance of m6A. m6A plays an essential role in diverse biological processes by recruiting the corresponding YTH domain-containing proteins, as well as recruiting additional translation initiation factors. Here, we provide an update on the various aspects of YTH domain-containing proteins, including an introduction to the YTH domain, the categories, distribution in cells, and biological roles of YTH proteins. Then we focus on the mechanisms that YTH proteins recognize m6A and mediate the fate of methylated-RNAs in eukaryotic cells.


Assuntos
Adenosina/análogos & derivados , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Adenosina/metabolismo , Sítios de Ligação , Epigênese Genética , Ligação Proteica , Domínios Proteicos , RNA Mensageiro/química , RNA Mensageiro/metabolismo
4.
Zhonghua Fu Chan Ke Za Zhi ; 53(3): 172-177, 2018 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-29609231

RESUMO

Objective: To explore the human papilomavirus (HPV) genotypes and epithelial thickness of invisible cervical intraepithelial neoplasia Ⅲ (CIN Ⅲ) under colposcopy. Methods: One hundred and sixty-nine biopsies from 93 patients with a final diagnosis of CIN Ⅲ were extracted from the Shenzhen cervical cancer screening trial Ⅱ (SHENCCAST Ⅱ) . The SHENCCAST Ⅱ was conducted from 2009 to 2010. All the cervical blocks from these patients were re-cut and placed on 6 slides, i.e. sandwich model, with the top and bottom sections being stained with HE, the top second be processed for other studies, 3 sections for HPV genotypes by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) assay. The thickness of squamous epithelium of CIN Ⅲ was measured by a microscope (×10) after re-cut. Colposcope directed CIN Ⅲ biopsies positively was defined as visible CIN Ⅲ, while random CIN Ⅲ biopsies positively was defined as invisible CIN Ⅲ. Results: HPV16 positivity was 37.2% (16/43) and 55.6% (70/126) between invisible and visible CIN Ⅲ biopsies, respectively (χ(2)=4.318, P=0.038) . Forty-nine cases of the 93 CIN Ⅲ patients were HPV16 positive, while 44 of them non-HPV16 positive. The proportion of patients with ≥45 years of age for other non-HPV16 positive 40.9% (18/44) was significantly higher than that HPV16 positive 20.4% (10/49; χ(2)=4.630, P=0.031) . Patients with HPV16 positive were more likely to have lesions ≥1 quadrant (χ(2)=7.786, P=0.005) than other non-HPV16 positive. Compared the average epithelium thickness of invisible CIN Ⅲ tissue (140±12) µm, the average epithelium thickness of visible CIN Ⅲ tissue (161±9) µm was thicker. There was statistical difference between two groups (t=4.383, P=0.038). The mean average epithelial thickness of CIN Ⅲ with HPV16 positive (172±11) µm was thicker than that the mean average epithelial thickness of CIN Ⅲ with non-HPV16 positive (130±10) µm (t=4.784, P=0.031) . Conclusions: Invisible lesions is difficult to identify under colposcopy and is related to non-HPV16 positive, small lesion size and thinner squamous epithelium. For non-HPV16 positive or older women should be performed colposcope directed biopsies and randomly multi-sites biopsies by colopscopy, which may be helpful to improve the detection of CIN Ⅲ and to reduce miss diagnosis.


Assuntos
Neoplasia Intraepitelial Cervical/diagnóstico , Colposcopia , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Biópsia , Neoplasia Intraepitelial Cervical/patologia , Detecção Precoce de Câncer , Feminino , Genótipo , Humanos , Gradação de Tumores , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/patologia , Gravidez , Manejo de Espécimes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Neoplasias do Colo do Útero/patologia
5.
Zhonghua Zhong Liu Za Zhi ; 40(3): 232-238, 2018 Mar 23.
Artigo em Chinês | MEDLINE | ID: mdl-29575846

RESUMO

Objective: To determine the morbidity of cervical intraepithelial neoplasia 2+ (CIN2+ ) and CIN3+ of different human papillomavirus(HPV) subtype infection combined with different cytology status. Methods: The Shenzhen Cervical Cancer Screening Trial Ⅰ & Ⅱ (SHENCCASTⅠ&Ⅱ) are population-based cross-sectional cervical cancer screening studis conducted in Shenzhen and surrounding area from 2008 to 2010. A total of 12 097 women who aged 25-59 years were included in the analysis. All of these women were detected by liquid-based cytology test and several high-risk HPV-DNA tests. The ones with HPV positive or atypical squamous cells of undetermined sign (ASC-US) were sequentially conducted by cervical biopsy vaginoscopy. Finally, 10 805 samples with complete data of hybrid capture 2(HC2), the polymerase chain reaction-based matrix-assisted laser desorption/ionization time-of-flight assay (MALDI-TOF), HPV genotyping detection, cytology and pathology results were analyzed. Results: The top 6 infection rates of HR-HPV in CIN2+ and CIN3+ were HPV16, HPV52, HPV58, HPV33, HPV31, HPV18. The highest constituent ratio of cytology in CIN2+ and CIN3+ was high grade squamous intraepithelial lesion(HSIL). The morbidities of CIN2+ of patients infected with HPV16, HPV31, HPV58, HPV33, HPV18, HPV52 were 41.3%, 31.5%, 30.6%, 28.7%, 28.2%, 17.7%, respectively, while the morbidities of CIN3+ of those were 33.5%, 20.5%, 19.4%, 15.7%, 19.2%, 8.3%, respectively.The morbidities of CIN2+ in negative intraepithelial lesion or malignancy (NILM), ASC-US, low grade squamous intraepithelial lesion (LSIL), atypical squamous cell cannot exclude high-grade squamous intraepithelial lesion (ASC-H), high grade squamous intraepithelial lesion (HSIL), atypical glandular cell (AGC) samples were 0.4%, 6.9%, 11.1%, 36.4%, 82.0%, 16.7%, respectively, while the morbidities of CIN3+ of those were 0.2%, 3.1%, 4.2%, 22.7%, 64.8%, 0.0%, respectively. The morbidities of CIN2+ in NILM combined with HPV16, HPV18, HPV31, HPV33 infection were 12.6%, 13.3%, 15.8% and 11.5%, respectively, while the morbidities of CIN3+ of those were 10.3%, 11.1%, 7.9% and 7.7%, respectively.The morbidities of CIN2+ and CIN3+ in ASC-US combining with hrHPV infection were high, and the top 6 subtypes associated with high risk of CIN2+ were HPV31 (35.7%), HPV33 (26.9%), HPV16 (26.5%), HPV58 (22.4%), HPV52 (18.6%), HPV68 (15.4%), while those associated with high risk of CIN3+ were HPV16 (20.4%), HPV31 (14.3%), HPV33 (11.5%), HPV58 (8.6%), HPV68 (7.7%), HPV52 (5.8%). Conclusions: Cytology combined with HPV genotyping detection can more effectively estimate the morbidity risks of CIN2+ and CIN3+ . Both high prevalence rates and high risks associated with CIN2+ and CIN3+ of HPV31, HPV33, HPV52 and HPV58 are observed. NILM and ASC-US status combined with these subtypes mentioned above are advised to be conducted by colposcopy.


Assuntos
Neoplasia Intraepitelial Cervical/patologia , Neoplasia Intraepitelial Cervical/virologia , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto , Células Escamosas Atípicas do Colo do Útero , Colposcopia , Estudos Transversais , Feminino , Genótipo , Testes de DNA para Papilomavírus Humano , Papillomavirus Humano 16/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Gravidez , Risco
7.
J Mater Sci Mater Med ; 28(5): 76, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28386851

RESUMO

This study aimed to evaluate the in vivo osseointegration of implants with hydrophobic antimicrobial GL13K-peptide coating in rabbit femoral condyles by micro-CT and histological analysis. Six male Japanese Rabbits (4 months old and weighing 2.5 kg each) were included in this study. Twelve implants (3.75 mm wide, 7 mm long) were randomly distributed in two groups, with six implants in the experimental group coated with GL13K peptide and six implants in the control group without surface coating. Each implant in the test and the control group was randomly implanted in the left or right side of femoral condyles. On one side randomly-selected of the femur, each rabbit received a drill that was left without implant as control for the natural healing of bone. After 3 weeks of healing radiographic evaluation of the implant sites was taken. After 6 weeks of healing, rabbits were sacrificed for evaluation of the short-term osseointegration of the dental implants using digital radiography, micro-CT and histology analysis. To perform evaluation of osseointegration, implant location and group was double blinded for surgeon and histology/radiology researcher. Two rabbits died of wound infection in sites with non-coated implants 2 weeks after surgery. Thus, at least four rabbits per group survived after 6 weeks of healing. The wounds healed without suppuration and inflammation. No implant was loose after 6 weeks of healing. Radiography observations showed good osseointegration after 3 and 6 weeks postoperatively, which proved that the tissues followed a natural healing process. Micro-CT reconstruction and analysis showed that there was no statistically significant difference (P > 0.05) in volume of bone around the implant between implants coated with GL13K peptide and implants without coating. Histomorphometric analysis also showed that the mineralized bone area was no statistically different (P > 0.05) between implants coated with GL13K peptide and implants without coating. This study demonstrates that titanium dental implants with an antimicrobial GL13K coating enables in vivo implant osseointegration at similar bone growth rates than gold-standard non-coated dental implants up to 6 weeks of implantation in rabbit femurs.


Assuntos
Anti-Infecciosos/química , Implantação Dentária Endo-Óssea/métodos , Implantes Dentários , Osseointegração/efeitos dos fármacos , Peptídeos/química , Animais , Peso Corporal , Materiais Revestidos Biocompatíveis/química , Fêmur/patologia , Implantes Experimentais , Masculino , Coelhos , Distribuição Aleatória , Propriedades de Superfície , Titânio/química , Cicatrização , Microtomografia por Raio-X
8.
Genet Mol Res ; 15(2)2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27420961

RESUMO

The aim of this study was to evaluate the performance of three new high-risk human papillomavirus (HPV) assays for primary cervical cancer screening, by using self-collected samples, and to identify an HPV assay that could overcome the major obstacles faced during large-scale population-based screening. Two hundred and ten women showing abnormal cervical cytology (and referred for a colposcopy) were recruited in this study. Self-collected samples obtained from all women were tested with the Cobas, Seq, and BioPerfectus Multiplex Real Time HPV assays; simultaneously, clinician-collected samples (from the same women) were tested with the gold-standard Cobas HPV assay. The results of all the assays were consistent. The sensitivity, positive predictive value, and negative predictive value for cervical intraepithelial neoplasia 2+ (CIN2+) and CIN3+ were comparable between the self-collected samples tested with the three new assays and the clinician-collected samples tested with the Cobas HPV assay (P > 0.05). The single-genotype HPV load per sample did not differ significantly between the self- and clinician-collected samples (P = 0.195). In conclusion, the results of this study demonstrated the applicability of the three new HPV assays for primary cervical cancer screening based on self-collection.


Assuntos
Testes de DNA para Papilomavírus Humano/métodos , Autoexame/métodos , Manejo de Espécimes/métodos , Neoplasias do Colo do Útero/diagnóstico , Adolescente , Adulto , Feminino , Testes de DNA para Papilomavírus Humano/normas , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Autoexame/normas , Sensibilidade e Especificidade , Manejo de Espécimes/normas
9.
Genet Mol Res ; 14(2): 2994-3001, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25966063

RESUMO

This study investigated the incidences of urinary incontinence and pelvic organ prolapse as well as pelvic floor muscle strength after cesarean section and vaginal delivery. From June 2010 to July 2011, 149 puerpera in Shenzhen Hospital, Peking University, were divided into the cesarean section group (N = 66) and the vaginal delivery group (N = 83). Postpartum urinary incontinence analysis, pelvic examination, and pelvic muscle contraction analysis using the PHENIX neuromuscular therapy instrument were performed to compare urinary incontinence, pelvic organ prolapse, and pelvic floor muscle condition between the 2 groups. The incidences of urinary incontinence in the cesarean and vaginal delivery groups were 9.09% (6/66) and 16.87% (14/83), respectively (P > 0.05); the incidences of pelvic organ prolapse were 53.03% (35/66) and 86.75% (72/83), respectively (P < 0.05). There was no significant difference in pelvic muscle pressure or electrophysiological examination results between the 2 groups (P > 0.05). Hence, cesarean section has a protective effect on early postpartum pelvic organ prolapse, but the delivery modes do not differ significantly with respect to the incidence of postpartum urinary incontinence or pelvic muscle floor muscle strength.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Diafragma da Pelve/fisiologia , Prolapso de Órgão Pélvico/epidemiologia , Incontinência Urinária/epidemiologia , Adulto , Pequim/epidemiologia , Cesárea , Parto Obstétrico/métodos , Feminino , Humanos , Prolapso de Órgão Pélvico/etiologia , Período Pós-Parto , Gravidez , Incontinência Urinária/etiologia
10.
Clin Exp Obstet Gynecol ; 41(4): 399-401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25134284

RESUMO

OBJECTIVE: The current study explored the impact of gestational weight gain on postnatal pelvic muscle strength and the effect of low-frequency electrical stimulation combined with biofeedback training on strength recovery. MATERIALS AND METHODS: A total of 126 mothers six to eight weeks after term delivery were recruited at Peking University Shenzhen Hospital from August 2010 to July 2011. According to gestational weight gain, they were divided into two groups: the < 15 kg (A) and > or = 15 kg (B) groups. Pelvic floor muscle fibre strength was determined. Target low-frequency electrical stimulation combined with biofeedback training was conducted. After training, pelvic floor muscle fiber strength was determined again for effect evaluation. RESULTS: Before training, types I and II pelvic floor muscle fiber strength of group B was noticeably lower than that of group A (p < 0.05). After rehabilitation, the pelvic floor muscle strength of both groups significantly increased (p < 0.05). However, types I and II pelvic floor muscle fiber strength of group B was still significantly lower than that of group A (p < 0.05). CONCLUSION: Gestational weight gain negatively influences pelvic floor muscles. Low-frequency electrical stimulation combined with biofeedback training improves postnatal pelvic floor muscle fiber strength. A less gestational weight increase indicates faster postnatal pelvic muscle strength recovery and a better rehabilitative effect.


Assuntos
Biorretroalimentação Psicológica , Terapia por Estimulação Elétrica , Força Muscular/fisiologia , Gravidez/fisiologia , Ganho de Peso/fisiologia , Adulto , Eletromiografia , Feminino , Humanos , Contração Muscular/fisiologia , Diafragma da Pelve/fisiologia , Adulto Jovem
11.
Oncogene ; 29(41): 5559-67, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20676142

RESUMO

Normal tissue cells survive and proliferate only while anchored to solid substrate. Conversely, transformed cells both survive and proliferate following detachment, having lost attachment context through unclear mechanisms. p66(Shc) is a focal adhesion-associated protein that reports cell attachment through a RhoA-dependent mechanosensory test. We find that human small cell lung cancer (SCLC) cells and mouse Lewis lung carcinoma (LLC), which display aggressive metastatic behavior, lack both p66(Shc) and retinoblastoma (pRB) and bypass anoikis. Re-expression of p66(Shc) in these cells restores anoikis and provides striking protection from metastasis by LLC cells in vivo. Notably, knockdown of p66(Shc) in normal epithelial cells leads to unrestrained Ras activation, preventing anoikis through downstream suppression of RhoA but blocking proliferation in a pRB-dependent manner, thus mimicking oncogenic Ras. Conversely, LLC and SCLC cells display constitutive Ras activation necessary to bypass anoikis, which is reversed by re-expression of p66(Shc). p66(Shc) therefore coordinates Ras-dependent control of proliferation and anchorage sensation, which can be defeated in the evolution of highly metastatic tumors by combined loss of both p66(Shc) and pRB.


Assuntos
Anoikis , Carcinoma Pulmonar de Lewis/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Proteínas ras/metabolismo , Animais , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Adesões Focais , Humanos , Immunoblotting , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Interferência de RNA , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Proteínas Adaptadoras da Sinalização Shc/genética , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Proteínas ras/genética , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
12.
Br J Cancer ; 100(3): 532-7, 2009 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19127262

RESUMO

To evaluate alternative cervical cancer screening methods, digital colposcopy and collection of cervical exfoliated cells for liquid-based cytology (LBC) and hybrid capture 2 (HC2) testing were performed among 2562 women aged 15-59 years in three study sites in the People's Republic of China (rural Shanxi province, Shenyang city in Liaoning province and Shenzhen city in Guangdong province). Visual inspection with acetic acid (VIA) was also evaluated independently from colposcopy. A total of 74 cases of histologically confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+) were identified, and 16 CIN2+ cases were imputed among unbiopsied women to correct for verification bias. Corrected sensitivity for CIN2+ was 37% for VIA, 54% for colposcopy, 87% for LBC with a threshold of atypical cells of undetermined significance (LBC>or=ASCUS), 90% for HC2, 84% for LBC using HC2 to triage ASCUS and 96% for positivity to LBC>or=ASCUS or HC2. For VIA, sensitivity was much lower among women >or=40 years (12%) than those aged or=ASCUS or HC2, up to 94% for LBC using HC2 to triage ASCUS. In conclusion, LBC, HC2 and their combinations performed well, whereas VIA missed a majority of CIN2+, particularly in older women. Digital colposcopy performed better than VIA, but still missed nearly half of CIN2+ in this study.


Assuntos
Programas de Rastreamento/métodos , Neoplasias do Colo do Útero/diagnóstico , Adolescente , Adulto , China , Colposcopia , Feminino , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle
13.
Opt Lett ; 31(4): 489-91, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16496896

RESUMO

A wavelength-dependent polarization rotator is used to transform the orthogonal polarizations of the signal and idler of a near-degenerate type II KTP optical parametric oscillator (OPO) into a common polarization state. This common polarization allows a single ZnGeP2 OPO to fully utilize the 2 microm signal and idler KTP OPO outputs in a mid-IR conversion. The simple design of the wavelength-dependent polarization rotator yields a compact source that simultaneously generates four mid-JR wavelengths collinearly with a total mid-IR average power of 5.5 W at a >15 kHz pulse repetition rate.

14.
Virology ; 286(1): 62-71, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11448159

RESUMO

The HIV-1 accessory protein Tat has been found to exert profound effects on vascular cell behavior. Recently, Tat has been found to activate the c-Jun amino-terminal kinase (JNK1, SAPK) MAP kinase in lymphoid cells. We found that purified Tat rapidly activated JNK1 in human umbilical vein endothelial cells and ECV-304 cells, and coculture of ECV-304 cells with Tat-transfected HeLa cells resulted in persistent activation of JNK1. In addition, lower doses of Tat potentiated TNFalpha-induced JNK1 activation, although higher doses paradoxically diminished JNK1 activation by TNFalpha. Treatment of ECV-304 cells with Tat acutely increased intracellular oxidant levels, and Tat-induced oxidant activity was decreased by two structurally distinct NADPH oxidase inhibitors, diphenylene iodonium and apocynin. Both oxidase inhibitors and the thiol antioxidant N-acetyl cysteine decreased Tat-induced JNK1 activation in parallel with reduction in oxidant levels. Activation of JNK1 by Tat was also inhibited by cytochalasin B, suggesting that Tat signaling was dependent upon intact cytoskeletal function. Indeed, JNK1 activation by Tat was associated with actin microfilament rearrangement. We conclude that HIV Tat may cause acute and persistent activation of the JNK MAP kinase through activation of a specific oxidase.


Assuntos
Produtos do Gene tat/fisiologia , Infecções por HIV/virologia , HIV-1/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Linhagem Celular , Ativação Enzimática , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , NADPH Oxidases/fisiologia , Oxirredução , Transdução de Sinais , Replicação Viral/fisiologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana
15.
Opt Express ; 8(13): 694-8, 2001 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-19421260

RESUMO

We have achieved 4.1W of 3.5-micron output from a non-critically phasematched (NCPM), type II, KTiOAsO4 (KTA) optical parametric oscillator (OPO) pumped within the cavity of a Q-switched diode-pumped Nd: YALO laser operating at 10kHz. We adopted the simplest configuration with a compact diode-pumped Nd: YALO module pumping the singly resonant KTA OPO. Besides 4.1W of 3.5um, 10.9W of 1.5 micron and 11.3W of 1-micron radiation were obtained simultaneously.

16.
Opt Lett ; 25(9): 619-21, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18064129

RESUMO

We present what is to our knowledge the first demonstration of a 4.7-W cw Tm:YAG. This proof-of-principle experiment clearly demonstrates the possibility of using a pump absorption that is 2 orders of magnitude (~0.0078 cm(-1)) less than that of the conventional pump absorption (typically >1 cm(-1)). This Tm:YAG laser is pumped intracavity within a Nd:YAG laser for multiple-pass absorption. The maximum conversion efficiency of 2.02 mum is 20%, with a slope efficiency of 35% with respect to the absorbed 1.064-mum power.

17.
Opt Lett ; 25(19): 1460-2, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18066248

RESUMO

We report on an intracavity optical parametric oscillator (OPO) placed within a compact diode-pumped Nd:YALO laser cavity. This OPO utilizes a pair of KTP crystals, which are diffusion bonded together in a walk-off-compensated configuration. We have generated up to 21.4 W of 2-mum radiation, operating in a few-kilohertz range.

18.
Opt Lett ; 25(21): 1591-3, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18066286

RESUMO

We present a 120-W cw diode-pumped Tm:YAG laser. The Tm:YAG rod is side pumped by three diode arrays whose radiation is coupled through compound parabolic concentrators. The maximum optical-to-optical conversion efficiency of the 2.02-mum laser output is 25.2%, with a slope efficiency of 31.2%.

19.
Arch Biochem Biophys ; 371(1): 15-23, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10525284

RESUMO

Amino and carboxyl termini of the bifunctional enzyme Fru 6-P, 2-kinase:Fru 2,6-bisphosphatase regulate the relative activities of the kinase/phosphatase. The N-terminus of the rat liver bifunctional enzyme is highly basic, containing a protein kinase A phosphorylation site that regulates these enzyme activities in a reciprocal manner. To determine the role of charged residues in the N-terminal peptide, mutant enzymes were constructed in which these residues were altered to residues carrying opposite charges, and the effect on the catalytic properties, thermal lability, and susceptibility to trypsin digestion and phosphorylation by protein kinase A was determined. Most of these mutations decreased k(cat)/K(ATP) and/or k(cat)/K(Fru) (6-P) of the kinase and increased k(cat)/K(Fru 2,6-P2) of the phosphatase. These mutant enzymes were more susceptible to trypsin digestion, phosphorylation by protein kinase A, and thermal inactivation. In general, the effect was greater with amino acid residues located more distant from the N-terminus. The resulting changes were not as large as observed with the phosphorylated enzyme. Mutation of Ser22 to Pro produced large changes in the kinetic properties comparable to those of phosphorylation, suggesting that the flexible region of the N-terminus containing five serines (Ser20 to S24) is essential for the enzyme activities. These results indicated that the charged residues as well as Ser20-Ser24 in the N-terminus of the liver Fru 6-P,2-kinase:Fru 2,6-Pase are essential in the allosteric regulation and probably involved in interactions with the catalytic domains that induce a conformation that has high Fru 6-P,2-kinase and low Fru 2,6-Pase activities. Any disruption of this N-terminal interaction results in inhibition of the kinase and activation of the phosphatase.


Assuntos
Fígado/enzimologia , Monoéster Fosfórico Hidrolases/química , Monoéster Fosfórico Hidrolases/metabolismo , Substituição de Aminoácidos , Animais , Clonagem Molecular , Primers do DNA , Escherichia coli , Cinética , Mutagênese Sítio-Dirigida , Fosfofrutoquinase-2 , Monoéster Fosfórico Hidrolases/genética , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Biol Chem ; 274(2): 1100-7, 1999 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-9873057

RESUMO

Transcription of the liver type pyruvate kinase and lipogenesis enzyme genes is induced by high carbohydrate in liver. We have found a novel protein factor in rat liver nuclei that binds to the glucose response element (CACGTG motifs) of the pyruvate kinase gene (Liu, Z. , Thompson, K. S., and Towle, H. C. (1993) J. Biol. Chem. 268, 12787-12795) and the "insulin response element" of fatty acid synthase gene. The amounts of this DNA-binding protein, termed "glucose response element binding protein" (GRBP) in the nuclear extract, were increased in liver by a high carbohydrate diet and decreased by starvation, high fat, and high protein diet. GRBP also occurs in cytosols of liver and is dependent on carbohydrate. Both the nuclear and the cytosolic GRBP showed similar properties, except the former was more resistant to thermal inactivation than the latter. Kinetics of glucose activation of the cytosolic GRBP in a primary culture of hepatocytes indicated that a half-maximum activation was achieved after 6 h, and glucose concentration required for the maximum activation of the GRBP was approximately 12 mM. Dibutyryl-cAMP, okadaic acid, and forskolin inhibited glucose activation of both GRBP and liver pyruvate kinase transcription. These results suggested that GRBP may be a factor that recognizes the glucose response motif site and may be involved in mediating carbohydrate response of the pyruvate kinase gene.


Assuntos
Ácido Graxo Sintases/metabolismo , Glucose/metabolismo , Fígado/enzimologia , Piruvato Quinase/genética , Animais , Sequência de Bases , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/farmacologia , Primers do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Fígado/citologia , Masculino , Dados de Sequência Molecular , Ácido Okadáico/farmacologia , Ratos , Ratos Sprague-Dawley
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