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1.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728703

RESUMO

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

2.
Phys Rev Lett ; 130(21): 216004, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295091

RESUMO

There has been a long-standing debate about the mechanism of the unusual superconductivity in alkali-intercalated fullerides. In this Letter, using high-resolution angle-resolved photoemission spectroscopy, we systematically investigate the electronic structures of superconducting K_{3}C_{60} thin films. We observe a dispersive energy band crossing the Fermi level with the occupied bandwidth of about 130 meV. The measured band structure shows prominent quasiparticle kinks and a replica band involving the Jahn-Teller active phonon modes, which reflects strong electron-phonon coupling in the system. The electron-phonon coupling constant is estimated to be about 1.2, which dominates the quasiparticle mass renormalization. Moreover, we observe an isotropic nodeless superconducting gap beyond the mean-field estimation (2Δ/k_{B}T_{c}≈5). Both the large electron-phonon coupling constant and large reduced superconducting gap suggest a strong-coupling superconductivity in K_{3}C_{60}, while the electronic correlation effect is suggested by the observation of a waterfall-like band dispersion and the small bandwidth compared with the effective Coulomb interaction. Our results not only directly visualize the crucial band structure but also provide important insights into the mechanism of the unusual superconductivity of fulleride compounds.


Assuntos
Álcalis , Elétrons , Espectroscopia Fotoeletrônica
3.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493436

RESUMO

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.


Assuntos
Eletricidade , Elétrons
4.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493447

RESUMO

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.


Assuntos
Núcleo Celular , Fótons
5.
Zhonghua Wai Ke Za Zhi ; 60(3): 223-229, 2022 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-35078297

RESUMO

Objective: To investigate the efficacy and safety of a new cervical artificial disc prosthesis in the treatment of cervical degenerative diseases. Methods: The clinical data of 18 patients with single-level cervical degenerative diseases who underwent three dimensional printed anatomical bionic cervical disc replacement at Department of Spinal Surgery,Honghui Hospital,Xi'an Jiaotong University from May 2019 to July 2020 were analyzed retrospectively. There were 7 males and 11 females,aged (45±8) years old(range:28 to 58 years).The surgical segment was located at C3-4 level in 2 cases, C4-5 level in 5 cases, C5-6 level in 9 cases, and C6-7 level in 2 cases.The clinical and radiographic outcomes were recorded and compared at preoperative,postoperative times of one month and twelve months.The clinical assessments contained Japanese orthopedic association (JOA) score,neck disability index (NDI) and visual analogue scale (VAS).Imaging assessments included range of motion (ROM) of cervical spine, prosthesis subsidence and prosthesis anteroposterior migration.Repeated measurement variance analysis was used for comparison between groups,and paired t test was used for pairwise comparison. Results: All patients underwent the operation successfully and were followed up for more than 12 months.Compared with preoperative score,the JOA score,NDI and VAS were significantly improved after surgery (all P<0.01).There was no significant difference in postoperative ROM compared with 1-and 12-month preoperative ROM (t=1.570,P=0.135;t=1.744,P=0.099). The prosthesis subsidence was (0.29±0.13) mm (range: 0.18 to 0.50 mm) at 12-month postoperatively.The migration of prosthesis at 12-months postoperatively were (0.71±0.20) mm (range: 0.44 to 1.08 mm).There was no prosthesis subsidence or migration>2 mm at 12-month postoperatively. Conclusion: Three dimensional printed anatomical biomimetic cervical artificial disc replacement has a good early clinical effect in the treatment of cervical degenerative diseases, good mobility can be obtained while maintaining stability.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Substituição Total de Disco , Adulto , Biomimética , Vértebras Cervicais/cirurgia , Feminino , Seguimentos , Humanos , Disco Intervertebral/cirurgia , Degeneração do Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Estudos Retrospectivos , Substituição Total de Disco/métodos , Resultado do Tratamento
6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(4): 640-646, 2021 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-34393221

RESUMO

OBJECTIVE: To investigate the clinicopathological features and prognosis of fumarate hydratase deficient renal cell carcinoma (FH-RCC). METHODS: Immunohistochemical (IHC) staining was used to detect the expression of fumarate hydratase (FH) in tumor tissues of 109 different types of renal cell carcinoma (RCC) patients aged 60 years and younger from the Department of Urology of Peking University First Hospital from January 2013 to December 2019. The clinicopathological data and prognosis of FH-RCC were collected and analyzed. RESULTS: There were eleven patients with FH-negative expression. Seven were males and four females. The age of onset ranged 16-53 years (mean age: 36.7 years), and four female patients all had a history of uterine leiomyoma. Only one first-degree relative of one patient had renal cancer, and none of the patients had a history or family history of cutaneous leiomyomas. The diameter of the tumor was 2.1-12.0 cm (mean: 8.83 cm). Renal sinus or perirenal fat invasion was seen in nine cases, tumor thrombus in renal vein or inferior vena cava in six cases, lymph node metastasis in seven cases, adrenal gland invasion in four cases and splenic capsule invasion in one case. The cases were initially diagnosed as type Ⅱ papillary RCC (7/49, 14.3%), collecting duct carcinoma (2/9, 22.2%) and unclassified RCC (2/51, 3.9%). Tumor histopathology mostly showed a mixture of different structures, such as papillary, tubular cystic, solid, and so on. The most common histological structures were papillary (9/11, 81.8%) and tubular (8/11, 72.7%). Three cases had sarcomatoid areas. At least focal eosinophilic nucleolus (WHO/grades Ⅲ-Ⅳ) and perinuclear halo could be seen in all cases. Immunohistochemical (IHC) stains of most tumors were negative for CA9, CD10 and CK7. The results of fluorescence in situ hybridization (FISH) showed that there was no translocation or amplification of TFE3 gene in two cases with TFE3 IHC expression. All the patients were followed up for 11-82 months. Mean survival was 24 months. Five cases died of distant metastasis 9-31 months after operation (mean: 19 months), and five of the six patients alive had became metastatic. CONCLUSION: Morphologically, FH-RCC overlaps with many types cell RCC. A mixture of papillary and tubular cystic arrangement is the most common growth pattern of FH-RCC. At least focally large and obvious eosinophilic nucleoli are an important histological feature of this tumor. The negative expression of FH can help to confirm the diagnosis. Young female RCC patients with uterine leiomyomas should be suspected of FH-RCC. Some FH-RCC cases lack clinical evidence. The suspicion raised by pathologists based on histological characteristics is often the key step to further genetic testing and the final diagnosis of the tumor.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Adolescente , Adulto , Biomarcadores Tumorais , Carcinoma de Células Renais/genética , Feminino , Fumarato Hidratase/genética , Humanos , Hibridização in Situ Fluorescente , Neoplasias Renais/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
7.
Acta Endocrinol (Buchar) ; 17(3): 351-357, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35342461

RESUMO

Objective: To investigate the correlation between serum levels of 25-hydroxy vitamin D [25(OH)D] and the visceral fat area of patients with type 2 diabetes mellitus (T2DM) in the context of different bone mass. Materials and Methods: A total of 180 patients with T2DM were randomly selected for bone mineral density (BMD) examination. According to the results, they were divided into three groups: T2DM normal bone group (group A); T2DM bone mass reduction group (group B); T2DM osteoporosis group (group C). Result: Serum 25(OH)D levels in NC group, A group, B group and C group decreased in turn, and Visceral fat area (VFA) in group B and group C were significantly higher than those in group A and NC [(29.41±4.87) vs. (22.76±4.23) vs. (17.78±3.61) vs. (9.70±3.01), P<0.05], [(117.76±38.79), (125.08±37.90) vs. (89.79±26.51), (97.53±28.61), P<0.05]. Pearson correlation analysis showed that L1-L4 lumbar vertebrae bone density was positively correlated with 25(OH)D and VFA; left femoral neck bone density was positively correlated with 25(OH)D, and negatively correlated with VFA. Conclusion: Serum 25(OH)D and VFA may be associated with the development of T2DM combined with OP.

8.
Phys Rev Lett ; 124(11): 111301, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32242731

RESUMO

We report constraints on the dark photon effective kinetic mixing parameter (κ) with data taken from two p-type point-contact germanium detectors of the CDEX-10 experiment at the China Jinping Underground Laboratory. The 90% confidence level upper limits on κ of solar dark photon from 205.4 kg-day exposure are derived, probing new parameter space with masses (m_{V}) from 10 to 300 eV/c^{2} in direct detection experiments. Considering dark photon as the cosmological dark matter, limits at 90% confidence level with m_{V} from 0.1 to 4.0 keV/c^{2} are set from 449.6 kg-day data, with a minimum of κ=1.3×10^{-15} at m_{V}=200 eV/c^{2}.

9.
Helminthologia ; 57(3): 196-210, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32855607

RESUMO

Paragonimus proliferus (P. proliferus), one of 46 Paragonimus species registered in the National Center for Biotechnology Information database, may be much more widely distributed in Southeast Asia than previously thought, as its reported natural foci have increased in the past decades. However, very little is known about its molecular biology, especially at the transcriptome level. For the first time, the transcriptome of this species was sequenced and compared with four other common Paragonimus species, namely Paragonimus skrjabini, Paragonimus kellicotti, Paragonimus miyazakii, and Paragonimus westermani, to predict homologous genes and differentially expressed homologous genes to explore interspecies differences of Paragonimus proliferus. A total of 7393 genes were found to be significantly differentially expressed. Of these, 49 were considered to be core genes because they were differentially expressed in all four comparison groups. Annotations revealed that these genes were related mainly to "duplication, transcription, or translation", energy or nutrient metabolism, and parasitic growth, proliferation, motility, invasion, adaptation to the host, or virulence. Interestingly, a majority (5601/7393) of the identified genes, and in particular the core genes (48/49), were expressed at lower levels in P. proliferus. The identified genes may play essential roles in the biological differences between Paragonimus species. This work provides fundamental background information for further research into the molecular biology of P. proliferus.

10.
Ann Oncol ; 30(10): 1630-1637, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31373615

RESUMO

BACKGROUND: Previous mass screening studies have shown that IgA antibodies against Epstein-Barr Virus (EBV) can facilitate early detection of nasopharyngeal carcinoma (NPC), but the impact of EBV-antibody screening for NPC-specific mortality remains unknown. PATIENTS AND METHODS: A prospective, cluster randomized, controlled trial for NPC screening (PRO-NPC-001) was conducted in 3 selected towns of Zhongshan City and 13 selected towns of Sihui City in southern China beginning in 2008. Serum samples of the screening group were tested for two previously selected anti-EBV antibodies. Subjects with serological medium risk were subsequently retested annually for 3 years, and those with serological high risk were referred to otorhinolaryngologists for diagnostic check-up. An interim analysis was carried out to evaluate the primary end points of the NPC-specific mortality and the early diagnostic rate, and the secondary end point of the NPC incidence, through linkage with the database of Zhongshan City. RESULTS: Among 70 296 total subjects, 29 413 screened participants (41.8% of the total subjects) in the screening group and 50 636 in the control group, 153 (43.3 per 100 000 person-year), 62 (55.3 per 100 000 person-year) and 99 (33.1 per 100 000 person-year) NPC cases were identified. The early diagnostic rates of NPC were significantly higher in the participants (79.0%, P < 0.0001) and the screening group (45.9%, P < 0.0001) compared with the control group (20.6%). Although no differences were found between NPC-specific mortality of the screening group and the control group [relative risk (RR)= 0.82, 95% confidence interval (CI) 0.37-1.79], lower NPC-specific mortality was noticed among participants from the screening group versus the control group (RR = 0.22, 95% CI 0.09-0.49). CONCLUSION: IgA antibodies against EBV can identify high-risk population and was effective in screening for early asymptomatic NPC. Although the mortality reduction was not significant in the primary end point, we noted encouraging evidence of a mortality reduction in screening participants in this interim analysis. CLINICAL TRIAL NUMBER: NCT00941538.


Assuntos
Detecção Precoce de Câncer/métodos , Infecções por Vírus Epstein-Barr/complicações , Carcinoma Nasofaríngeo/epidemiologia , Carcinoma Nasofaríngeo/mortalidade , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/mortalidade , Adulto , Anticorpos Antivirais/sangue , Biomarcadores Tumorais/análise , Estudos de Casos e Controles , China/epidemiologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Herpesvirus Humano 4/isolamento & purificação , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/virologia , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida , Carga Viral
11.
Phys Rev Lett ; 123(16): 161301, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702340

RESUMO

We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (m_{χ}) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in m_{χ} are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σ_{χN}^{SI} at 90% confidence level are derived as 2×10^{-32}∼7×10^{-35} cm^{2} for TI analysis at m_{χ}∼50-180 MeV/c^{2}, and 3×10^{-32}∼9×10^{-38} cm^{2} for AM analysis at m_{χ}∼75 MeV/c^{2}-3.0 GeV/c^{2}.

12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(4): 569-574, 2017 08 18.
Artigo em Chinês | MEDLINE | ID: mdl-28816267

RESUMO

OBJECTIVE: To investigate the mechanisms of nuclear export signal of androgen receptor (NESAR) in the regulation of androgen receptor (AR) protein expression and stability in prostate cancer. METHODS: The green fluorescent protein fusion protein expression vectors pEGFP-AR(1-918aa), pEGFP-NESAR (743-817aa), pEGFP-NAR (1-665aa) and pEGFP-NAR-NESAR, and lysine mutants of NESAR pEGFP-NESAR K776R, pEGFP-NESAR K807R and pEGFP-NESAR K776R/K807R, were transiently transfected into prostate cancer cell line PC3. Fluorescence microscopy, Western blot and immunoprecipitation were used to detect NESAR regulation of androgen receptor stability. RESULTS: Under the fluorescence microscope, NESAR-containing fusion proteins were cytoplasmic localization, and their fluorescence intensities were much weaker than those without NESAR. The expression levels of NESAR-containing fusion proteins were significantly lower than those without NESAR. The half-lives of GFP-NESAR and GFP-NAR-NESAR were less than 6 h, while the expression of GFP and GFP-NAR was relatively stable and the half-life was more than 24 h in the presence of cycloheximide. The expression levels of GFP-NESAR were significantly increased by proteasome inhibitor MG132 treatment in a dose-dependent manner; in contrast, MG132 did not show any significant effect on the protein levels of GFP. When new protein synthesis was blocked, MG132 could also prevent the degradation of GFP-NESAR in the transfected cells in the presence of cycloheximide, while it had no significant effect on GFP protein stability in the parallel experiment. GFP immunoprecipitation showed that the ubiquitination level of GFP-NESAR fusion protein was significantly higher than that of the GFP control. The mutations of lysine sites K776 and K807 in NESAR significantly reduced the level of ubiquitination, and showed increased protein stability, indicating that they were the key amino acid residues of NESAR ubiquitination. CONCLUSION: NESAR was unstable and decreased the stability of its fusion proteins. NESAR was the target of polyubiquitination and mediated the degradation of its fusion proteins through the ubiquitin-proteasome pathway in prostate cancer cells. Our research provides a new way to regulate the level and/or activity of AR proteins, thus helping us understand the molecular mechanisms of AR degradation and strict control of AR in the progression to castration-resistance.


Assuntos
Sinais de Exportação Nuclear , Neoplasias da Próstata , Receptores Androgênicos , Androgênios , Linhagem Celular Tumoral , Humanos , Masculino , Sinais de Exportação Nuclear/fisiologia , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/fisiologia
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(4): 603-607, 2017 08 18.
Artigo em Chinês | MEDLINE | ID: mdl-28816273

RESUMO

OBJECTIVE: To evaluate the impacts of the prognostic factors of T2N0M0 upper tract urothelial carcinoma (UTUC) for Chinese patients. METHODS: A retrospective study was conducted including 235 patients who were diagnosed with T2N0M0 UTUC in our hospital and received radical nephroureterectomy (RNU) or partial ureterectomy during January 2000 and December 2013. The 3 and 5-year cancer-specific survival rates and bladder recurrence-free survival rates of all the patients were valued using Kaplan-Meier method, and the survival curves with statistical significance between the two were compared using the Log-rank test. Variables with significant differences in the univariate analysis were subjected to the multivariate analysis by Cox regression model. RESULTS: A total of 235 patients were included in this study, including 95 (40.4%) male patients and 140 (59.6%) female patients. The mean age was 66.73±10.49 years.The median follow-up time was 53 (rang: 3-142) months, and during the follow-up, 74 (31.5%) patients died of UTUC after a median of 35 months,and 96 (40.9%) patients developed intravesical recurrence after a median of 19.5 months. The 3 and 5-year cancer-specific survival rates of all the patients were 89.1% and 85.9%, respectively; the bladder recurrence-free survival rates were 85.5% and 80.2%, respectively. The independent prognostic factors of cancer-specific mortality were tumor age elder than 55 years (HR=3.138, 95%CI: 1.348-7.306, P=0.008) and diameter larger than 5 cm (HR=3.320, 95%CI: 1.882-5.857, P<0.001). The independent prognostic factors of bladder recurrence-free survival were ureter tumor (HR=1.757, 95%CI: 1.159-2.664, P=0.008) and lower tumor grade (HR=1.760, 95% CI: 1.151-2.692, P=0.009). CONCLUSION: T2N0M0 UTUC has a better cancer-specific survival. The intravesical recurrence was equivalent to non-muscle invasive UTUC but earlier. The tumor diameter larger than 5 cm and the patient age elder than 55 years were independently associated with cancer-specific mortality; the primary tumor located in ureter and lower tumor grade were more likely to develop intravesical recurrence.


Assuntos
Carcinoma de Células de Transição , Nefrectomia , Neoplasias da Bexiga Urinária , Idoso , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Estudos Retrospectivos , Ureter , Neoplasias Ureterais , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(2): 265-272, 2024 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-38413067

RESUMO

Objective: To explore high-risk sexual behaviors of HIV/AIDS and related factors in young students in Guangzhou. Methods: A cross-sectional survey was conducted in 5 different types of Guangzhou colleges by convenience sampling with minimum number of classes per grade and 600 samples per school from September to November 2021. The R 4.2.2 software was used to consolidate databases. Simultaneously, a logistic regression model and a decision tree algorithm model, stratifying by whether sexual behaviors had occurred before, were constructed. In each layer, the prediction performance of the two models was evaluated through area under receiver operating characteristic and the confusion matrix, and then the model with high prediction performance was retained. Results: A total of 7 346 students were surveyed. The proportion of the respondents reporting sexual experience were 9.08% (667/7 346), in whom 26.24% (175/667) had risky sexual activity in the past year. The decision tree algorithm model performs well in predicting whether high-risk sexual behaviors have occurred in the past year. When the complexity parameter value is 0.018, and nsplit reaches 4, which means there are 5 leaf nodes in the model, the cross error of the tree will be the smallest. The first best grouping variable in the decision tree was whether to use condoms throughout the first sexual behavior. If condoms were used at their sexual debut, but homosexual practices have occurred in the past year, the probability of risky sexual behavior will increase. If homosexual practices have not occurred in the past year, but the age of sexual debut was below 18 years old while the period of HIV education was after high school, the probability of risk sexual behavior will also increase. Conclusions: AIDS-related risky behaviors of young students still deserved attention. The experience of sexual debut and whether AIDS-related health education has been received before the sexual debut were significant predictors for the occurrence of high-risk sexual behavior. The decision tree algorithm model has particular applicability for predicting and screening potential risk populations.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Adolescente , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Estudos Transversais , Comportamento Sexual , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Preservativos , Fatores de Risco , Estudantes , Assunção de Riscos , Conhecimentos, Atitudes e Prática em Saúde
15.
Insect Mol Biol ; 22(1): 72-87, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23211014

RESUMO

Eukaryotic horizontal gene transfer (HGT) events are increasingly being discovered yet few reports have summarized multiple occurrences in a wide range of species. We systematically investigated HGT events in the order Lepidoptera by employing a series of filters. Bombyx mori, Danaus plexippus and Heliconius melpomene had 13, 12 and 12 HGTs, respectively, from bacteria and fungi. These HGTs contributed a total of 64 predicted genes: 22 to B. mori, 22 to D. plexippus and 20 to H. melpomene. Several new genes were generated by post-transfer duplications. Post-transfer duplication of a suite of functional HGTs has rarely been reported in higher organisms. The distributional patterns of paralogues for certain genes differed in the three species, indicating potential independent duplication or loss events. All of these HGTs had homologues expressed in some other lepidopterans, indicating ancient transfer events. Most HGTs were involved in the metabolism of sugar and amino acids. These HGTs appeared to have experienced amelioration, purifying selection and accelerated evolution to adapt to the background genome of the recipient. The discovery of ancient, massive HGTs and duplications in lepidopterans and their adaptive evolution provides further insights into the evolutionary significance of the events from donors to multicellular host recipients.


Assuntos
Transferência Genética Horizontal , Lepidópteros/genética , Animais , Evolução Biológica , Bombyx/genética , Etiquetas de Sequências Expressas , Genoma de Inseto , Lepidópteros/metabolismo , Filogenia , Seleção Genética
16.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(12): 1956-1962, 2023 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-38129153

RESUMO

Objective: To investigate the risk perception for risky behavior of HIV/AIDS infection among young students and to analyze the related influencing factors. Methods: A cross-sectional survey was conducted in 5 different types of Guangzhou colleges from September to November 2021, in which convenience sampling and a minimum number of classes per grade and 600 samples per school were used according to the national unity program. Disordered multi-classification logistic regression was used to construct a risk perception model and analyze influencing factors in different risk perception levels. Results: A total of 7 346 young students were surveyed, and most rated themselves at low risk of HIV/AIDS infections (90.58%, 6 654/7 346). A total of 89.10% (6 545/7 346) of subjects' perception of their HIV/AIDS infection risk was consistent with their risk behavior, while 10.90% (801/7 346) was inconsistent. Among those inconsistent subjects, 19.10% (153/801) showed underestimating their risk , while 80.90% (648/801) seen overestimating their risk. Disordered multi-classification logistic regression analysis showed that, after controlling for other factors, compared with the non-sexual group, respondents whose first sex age under 18 had a higher rate of underestimating their risk of infection (OR=129.39, 95%CI: 73.28-228.48), as well as a higher rate of overestimated their risk of infection (OR=1.76, 95%CI: 1.04-2.99). First sexual intercourse at age 18 or older was a risk factor for underestimating risk (OR=70.56, 95%CI: 42.72-116.53), but was not statistically associated with overestimating risk. Being female, other school type, non-heterosexual orientation, and self-rated HIV-related knowledge as fair or no knowledge were risk factors for overestimating risk but were not statistically associated with underestimating risk. Conclusions: Overall, young students in universities of Guangzhou have a good risk perception of HIV/AIDS infection. Individual factors, education factors and sexual experience will influence students' risk perception of HIV/AIDS infection. Raising the awareness rate of HIV/AIDS knowledge and delaying the age of first sexual intercourse will improve the risk perception ability of young students.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Feminino , Adolescente , Masculino , Estudos Transversais , Infecções por HIV/epidemiologia , Comportamento Sexual , Estudantes , Inquéritos e Questionários , Percepção , Conhecimentos, Atitudes e Prática em Saúde
17.
Sci Rep ; 12(1): 2346, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173182

RESUMO

Graphene is known as an atomically thin, transparent, highly electrically and thermally conductive, light-weight, and the strongest 2D material. We investigate disruptive application of graphene as a target of laser-driven ion acceleration. We develop large-area suspended graphene (LSG) and by transferring graphene layer by layer we control the thickness with precision down to a single atomic layer. Direct irradiations of the LSG targets generate MeV protons and carbons from sub-relativistic to relativistic laser intensities from low contrast to high contrast conditions without plasma mirror, evidently showing the durability of graphene.

18.
J Eur Acad Dermatol Venereol ; 25(11): 1299-303, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21241376

RESUMO

BACKGROUND: Human leucocyte antigen (HLA)-II alleles have been found to be associated with vitiligo in different populations, and several studies also suggested that HLA class II alleles/haplotypes were associated with a different type vitiligo. Of HLA class II alleles, DRB1*07 has consistently shown a positive association with vitiligo in Chinese Han population. OBJECTIVE: To further explore the relationship between DRB1*07 and vitiligo and to evaluate the DRB1*07 effect on the clinical features of vitiligo in Chinese Han population. METHODS: This study investigated DRB1*07 allele distribution in 1178 unrelated Chinese vitiligo patients and 1743 healthy controls using polymerase chain reaction/sequence specific primer method and observed clinical differences between DRB1*07 positive and DRB1*07 negative patients. RESULTS: The analysis of the 1178 cases and 1743 controls revealed a highly association between DRB1*07 allele and vitiligo [odds ratio (OR) = 1.97, P = 2.13 × 10(-17) ]. DRB1*07 positive patients had early disease onset (OR = 1.49, P = 0.001), higher frequency of family history (OR = 1.44, P = 0.006) compared with DRB1*07 negative patients. CONCLUSIONS: The DRB1*07 showed significant association with vitiligo in the study population. This study confirmed that DRB1*07 positive patients had some obvious clinical differences from DRB1*07 negative patients in the Chinese Han population.


Assuntos
Etnicidade , Cadeias HLA-DRB1/imunologia , Vitiligo/patologia , Alelos , Estudos de Casos e Controles , China , Cadeias HLA-DRB1/genética , Humanos , Vitiligo/imunologia
19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(10): 1871-1875, 2021 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814626

RESUMO

The conventional analytical methods cannot effectively adjust for time-varying confounding that occur in a longitudinal study and thus cannot correctly estimate the causal effects. This study explains the necessity of precisely controlling time-varying confounding and outlines G methods, including parametric g-formula, inverse probability of weighting, and G-estimation. We also compare the methods above to provide a reference for correctly estimating causal effects in the longitudinal study.


Assuntos
Modelos Estatísticos , Causalidade , Humanos , Estudos Longitudinais , Probabilidade
20.
J Int Med Res ; 38(1): 150-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20233524

RESUMO

This epidemiological study was conducted to investigate the prevalence of metabolic syndrome and associated risk factors in Chinese subjects from Dehui in north-eastern China. Using a random sampling method, a questionnaire was completed by 3785 permanent residents aged 18 - 72 years and relevant clinical data were collected from each subject. Binary multivariate logistic regression analysis was used to identify factors that were significantly associated with metabolic syndrome. Based on the International Diabetes Federation definition, the prevalence of metabolic syndrome was 22.4%, which is higher than that of the general Chinese population. Metabolic syndrome occurred more frequently in females and the prevalence gradually increased with age. Living in an urban setting and being female, > 50 years old, overweight, having total cholesterol > or = 5.18 mmol/l, low-density lipoprotein cholesterol > or = 3.1 mmol/l, and a fatty liver were significant risk factors associated with metabolic syndrome.


Assuntos
Síndrome Metabólica/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
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