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1.
Nature ; 614(7946): 48-53, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725994

RESUMEN

Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams1. The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon2. Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, FA, can be measured from neutrino scattering from free nucleons, νµn → µ-p and [Formula: see text], as a function of the negative four-momentum transfer squared (Q2). Up to now, FA(Q2) has been extracted from the bound nucleons in neutrino-deuterium scattering3-9, which requires uncertain nuclear corrections10. Here we report the first high-statistics measurement, to our knowledge, of the [Formula: see text] cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA11 experiment, extracting FA from free proton targets and measuring the nucleon axial charge radius, rA, to be 0.73 ± 0.17 fm. The antineutrino-hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations12-15. Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments16-20 to better constrain neutrino interaction models.

2.
IEEE Trans Inf Theory ; 70(1): 509-531, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39036782

RESUMEN

Motivated by applications in single-cell biology and metagenomics, we investigate the problem of matrix reordering based on a noisy disordered monotone Toeplitz matrix model. We establish the fundamental statistical limit for this problem in a decision-theoretic framework and demonstrate that a constrained least squares estimator achieves the optimal rate. However, due to its computational complexity, we analyze a popular polynomial-time algorithm, spectral seriation, and show that it is suboptimal. To address this, we propose a novel polynomial-time adaptive sorting algorithm with guaranteed performance improvement. Simulations and analyses of two real single-cell RNA sequencing datasets demonstrate the superiority of our algorithm over existing methods.

3.
Phys Rev Lett ; 131(1): 011801, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37478458

RESUMEN

Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high statistic differential cross sections are reported for the semiexclusive reaction ν_{µ}A→µ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{µ} beam with ⟨E_{ν}⟩≈6 GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.

4.
Phys Rev Lett ; 131(5): 051801, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595210

RESUMEN

MINERvA has measured the ν_{µ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{µ} energies and at produced π^{+} energies and angles, E_{π}>1 GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10 GeV.

5.
Phys Rev Lett ; 130(16): 161801, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37154647

RESUMEN

This Letter presents the first simultaneous measurement of the quasielasticlike neutrino-nucleus cross sections on C, water, Fe, Pb, and scintillator (hydrocarbon or CH) as a function of longitudinal and transverse muon momentum. The ratio of cross sections per nucleon between Pb and CH is always above unity and has a characteristic shape as a function of transverse muon momentum that evolves slowly as a function of longitudinal muon momentum. The ratio is constant versus longitudinal momentum within uncertainties above a longitudinal momentum of 4.5 GeV/c. The cross section ratios to CH for C, water, and Fe remain roughly constant with increasing longitudinal momentum, and the ratios between water or C to CH do not have any significant deviation from unity. Both the overall cross section level and the shape for Pb and Fe as a function of transverse muon momentum are not reproduced by current neutrino event generators. These measurements provide a direct test of nuclear effects in quasielasticlike interactions, which are major contributors to long-baseline neutrino oscillation data samples.

6.
Acta Orthop Belg ; 89(4): 719-726, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38205766

RESUMEN

Treatment of fibular fractures associated with extra-articular distal tibia fractures is technically challenging and the purpose of this study was to evaluate the use of intramedullary nail fixation of fibular fractures when associated with this fracture. Between January 2018 and December 2021, 33 patients presenting extra-articular distal tibia fractures and fibular fractures (AO/OTA 43A) were treated. Clinical and radiological data were collected during routine postoperative follow-ups. Thirty-one patients were monitored for a period of time ranging from 12 to 23 months, with an average follow-up of 17.5 ± 3.3 months. Fibular bone union took an average of 3.6 ± 0.9 months. At the last follow-up, the average fibular alignment and postoperative ankle talocrural angles were 1.8° and 9.1°, respectively. No detectable radiographic rotational malalignment and serious complications related to the fibular incision was observed. The average AOFAS and OMAS scores at the most recent follow-up were 88.3 ± 6.2 and 87.4 ± 6.0, respectively. Intramedullary nail fixation worked well to keep the fibula in place in fibular fractures connected to extra-articular distal tibia fractures.


Asunto(s)
Fracturas de Tobillo , Fracturas de la Tibia , Humanos , Tibia , Estudios Retrospectivos , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/cirugía , Peroné
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(5): 778-784, 2023 May 06.
Artículo en Zh | MEDLINE | ID: mdl-37165827

RESUMEN

Chronic pruritus seriously affects the quality of life of patients, which is closely related to stress, anxiety and depression. Prolonged and repeated pruritus can induce negative emotions such as anxiety and depression, while continued increased negative emotions can also promote exacerbation of pruritus, which drives the itch scratch cycle, thereby further aggravating skin damage. More and more studies have explored the mechanism of pruritus, anxiety and depression. This article mainly reviews the clinical relationship between pruritus and anxiety, depression and the new progress of its possible mechanism, providing reference for the prevention, control and effective treatment of chronic pruritus, anxiety and depression.


Asunto(s)
Ansiedad , Depresión , Prurito , Humanos , Prurito/psicología , Calidad de Vida , Enfermedad Crónica
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(2): 253-258, 2023 Feb 06.
Artículo en Zh | MEDLINE | ID: mdl-36797585

RESUMEN

The molecular genetic characteristics of a family with rare -88 C>G (HBB: c.-138 C>G) ß-thalassemia gene mutation were studied using cohort study. The cohort study was conducted from June to August 2022 by Prenatal Diagnosis Center of Sanya Women and Children's Hospital Managed by Shanghai Children's Medical Center. The phenotype and genotype were analyzed by hematological cytoanalyzer, automatic electrophoretic analysis system, and next-generation sequencing (NGS). And then, Sanger sequencing was used to verify the rare gene results. The results showed that the proband, her father, her uncle and her younger male cousin had discrete microcytosis (MCV 70.1 fl, 71.9 fl, 73.1 fl and 76.6 fl, respectively) and hypochromia (MCH 21.5 pg,22.0 pg,22.6 pg and 23.5 pg, respectively), elevated hemoglobin A2 level (5.3%, 5.4%, 5.4% and 5.5%, respectively), slightly elevated or normal fetal hemoglobin (Hb F), but no anemia. The proband was identified to have co-inherited ɑ-thalassemia (Hb Westmead gene heterozygous mutation, ɑwsɑ/ɑɑ) and ß-thalassemia with a rare -88 C>G (HBB: c.-138 C>G) heterozygous mutation (ß-88 C>G/ßN). Her mother had the same α-thalassemia as the proband. Her father, her uncle and her younger male cousin had the same rare -88 C>G heterozygous mutations as the proband. While her grandmother and younger brother were not carrier of thalassemia. In conclusion, 4 cases of rare -88 C>G(HBB:c.-138 C>G) heterozygous mutation had been detected in a Chinese family. Carriers of this beta-thalassemia are clinically asymptomatic. This study enriches the knowledge of the thalassemia mutation spectrum in Chinese people and provides valuable information for genetic counseling, prenatal diagnosis, and prevention of thalassemia, providing a scientific basis for improving the quality of birth population and preventing birth defects.


Asunto(s)
Talasemia alfa , Talasemia beta , Femenino , Humanos , Masculino , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/diagnóstico , China , Estudios de Cohortes , Genotipo , Biología Molecular , Mutación
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(10): 1590-1595, 2023 Oct 06.
Artículo en Zh | MEDLINE | ID: mdl-37859375

RESUMEN

To investigate the clinical efficacy and safety of dupilumab in the treatment of moderate to severe atopic dermatitis (AD) in China. A small sample self-controlled study before and after treatment was conducted to retrospective analysis patients with moderate to severe AD treated with dupilumab in the department of dermatology of the First Affiliated Hospital of Chongqing Medical University from July 2020 to March 2022. Dupilumab 600 mg was injected subcutaneously at week 0, and then 300 mg was injected subcutaneously every 2 weeks. The condition was evaluated by SCORAD(severity scoring of atopic dermatitis), NRS(numerical rating scale), DLQI(dermatology life quality index) and POEM(patient-oriented eczema measure). The improvement of SCORAD, NRS, DLQI and POEM was analyzed by paired t test and non-parametric paired Wilcoxon. The results showed that a total of 67 patients with moderate to severe AD received dupilumab treatment, of which 41 patients (the course of treatment was more than 6 weeks) had reduced the severity of skin lesions, improved quality of life and reduced pruritus. A total of 23 patients completed 16 weeks of treatment. At 4, 8, 12 and 16 weeks, SCORAD, NRS, DLQI and POEM decreased compared with the baseline, and the differences were statistically significant. SCORAD (50.13±15.19) at baseline, SCORAD (36.08±11.96)(t=6.049,P<0.001) at week 4,SCORAD (28.04±11.10)(t=10.471,P<0.001) at week 8, SCORAD (22.93±9.72)(t=12.428,P<0.001) at week 12, SCORAD (16.84±7.82)(t=14.609,P<0.001) at week 16, NRS 7(6,8) at baseline, NRS 4(3,5)(Z=-3.861,P<0.001) at week 4, NRS 2(1,4)(Z=-4.088,P<0.001) at week 8, NRS 1(0,2)(Z=-4.206,P<0.001) at week 12, NRS 2(0,2)(Z=-4.222,P<0.001) at week 16, DLQI (13.83±5.71) at baseline, DLQI (8.00±4.02)(t=6.325,P<0.001) at week 4, DLQI (5.61±3.50)(t=8.060,P<0.001) at week 8, DLQI (3.96±1.99)(t=8.717,P<0.001) at week 12, DLQI (2.70±1.89)(t=10.355,P<0.001) at week 16, POEM (18.04±6.41) at baseline, POEM (9.70±4.70)(t=7.031,P<0.001) at week 4, POEM (7.74±3.48)(t=8.806,P<0.001) at week 8, POEM (6.35±3.33)(t=10.474,P<0.001) at week 12, POEM (4.26±2.51)(t=11.996,P<0.001) at week 16. In the 16th week, 100%(23 patients), 91.3%(21 patients), 34.8%(8 patients) and 8.7%(2 patients) of 23 patients reached SCORAD30, SCORAD50, SCORAD70, and SCORAD90 statuses, respectively. There were 82.6%(19 patients), 95.7%(22 patients) and 95.7%(22 patients) of 23 patients with NRS, DLQI and POEM improved by≥4 points compared with baseline. Twelve patients with AD who continued to receive dupilumab after 16 weeks showed further improvement in skin lesions. The adverse events were conjunctivitis and injection site reaction. In conclusion, dupilumab is an effective and safe treatment for moderate and severe AD. However, the longer-term efficacy and safety require further studies involving larger sample sizes and a longer follow-up time.


Asunto(s)
Dermatitis Atópica , Humanos , Dermatitis Atópica/tratamiento farmacológico , Calidad de Vida , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
10.
Zhonghua Gan Zang Bing Za Zhi ; 31(2): 118-125, 2023 Feb 20.
Artículo en Zh | MEDLINE | ID: mdl-37137825

RESUMEN

Objective: To observe the efficacy and factors influencing sequential or combined tenofovir alafenamide fumarate (TAF) after treatment with entecavir (ETV) in patients with chronic hepatitis B (CHB) with low-level viremia (LLV). Methods: 126 CHB cases treated with ETV antiviral therapy in the Department of Infectious Diseases of the First Affiliated Hospital of Nanchang University from January 2020-September 2022 were retrospectively collected. Patients were divided into a complete virologic response (CVR) group (n = 84) and a low-level viremia (LLV) group (n = 42) according to the HBV DNA level during treatment. Clinical characteristics and laboratory indicators of the two groups at baseline and 48 weeks were analyzed by univariate analysis. Patients in the LLV group were divided into three groups according to their continued antiviral treatment regimen until 96 weeks: continued use of ETV as a control group; replacement of TAF as a sequential group; and combination of ETV and TAF as a combined group. The data of the three groups of patients were analyzed by one-way analysis of variance for 48 weeks. HBV DNA negative conversion rate, HBeAg negative conversion rate, alanine aminotransferase (ALT), creatinine (Cr), and liver stiffness test (LSM) were compared among the three groups after 96 weeks of antiviral treatment. Multivariate logistic regression was used to analyze the independent factors influencing the occurrence of HBV DNA non-negative conversion in LLV patients at 96 weeks. Receiver operating characteristic curve (ROC) was used to evaluate the effectiveness of predicting the occurrence of HBV DNA non-negative conversion in LLV patients at 96 weeks. Kaplan-Meier was used to analyze the cumulative negative rate of DNA in LLV patients, and the Log-Rank test was used for comparison. HBV DNA and HBV DNA negative conversion rates during treatment were observed dynamically. Results: Univariate analysis showed statistically significant differences in age, BMI, HBeAg positivity rate, HBV DNA, HBsAg, ALT, AST, and LSM at baseline between the CVR group and the LLV group (P < 0.05). Univariate analysis of variance revealed no statistically significant difference among the three groups of LLV patients at 48 weeks (P > 0.05). HBV-DNA negative conversion rate in the sequential group and the combination group was significantly higher than that in the control group after 96 weeks of treatment (88.89% vs. 41.18%, 85.71% vs. 41.18%, χ (2) = 10.404, P = 0.006). HBeAg negative conversion rate was higher than that of the control group, with no statistically significant difference (P > 0.05).Compared with the control group, ALT, Cr, and LSM in the sequential group and the combined group were equally improved to varying degrees, with a statistically significant difference (P < 0.05). Subsequent use of ETV and HBV DNA at 48 weeks were independent risk factors for HBV DNA positivity at 96 weeks in LLV patients (P < 0.05). The AUC of HBV DNA at 48 weeks was 0.735 (95%CI: 0.578 ~ 0.891), the cut-off value was 2.63 log(10) IU/ml, and the sensitivity and specificity were 76.90% and 72.40%, respectively. DNA conversion rate was significantly lower in LLV patients receiving 48-week ETV and 48-week HBV DNA≥2.63 log10 IU/mL than in patients receiving sequential or combined TAF and 48-week HBV DNA < 2.63 log(10) IU/mL. HBV DNA negative conversion rates in the sequential group and combined group at 72 weeks, 84 weeks, and 96 weeks were higher than those in the control group during the period from 48 weeks to 96 weeks of continuous treatment, and the differences were statistically significant (P < 0.05). Conclusion: Sequential or combined TAF antiviral therapy could more effectively improve the 96-week CVR rate, as well as hepatic and renal function, and alleviate the degree of hepatic fibrosis in CHB patients with LLV following ETV treatment. Subsequent use of ETV and HBV DNA load at 48 weeks were independent predictors of HBV DNA positivity at 96 weeks in LLV patients.


Asunto(s)
Hepatitis B Crónica , Humanos , Hepatitis B Crónica/tratamiento farmacológico , Antígenos e de la Hepatitis B , ADN Viral , Viremia/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento , Antivirales/uso terapéutico , Adenina/uso terapéutico , Fumaratos/uso terapéutico
11.
Zhonghua Yan Ke Za Zhi ; 59(6): 444-451, 2023 Jun 11.
Artículo en Zh | MEDLINE | ID: mdl-37264574

RESUMEN

Objective: To explore the characteristics of orthokeratology lenses designed for small correction zones and their effectiveness and safety in long-term prevention and control of myopia in children and adolescents. Methods: It was a prospective cohort study that included myopic children and adolescents who received corneal reshaping treatment at the Qingdao Eye Hospital of Shandong First Medical University between January 2019 and May 2020. The patients were randomly divided into two groups using computer-generated randomization, and were fitted with corneal reshaping lenses with small treatment zones and conventional designs, respectively. The uncorrected visual acuity, best-corrected visual acuity, refractive error, and axial length were measured before and after 6, 12, and 18 months of wearing the lenses. Corneal topography with the Pentacam was also performed, and the area and diameter of the corneal treatment zone were calculated using the Matlab software. Results: A total of 60 myopic patients (60 eyes) were enrolled, including 29 males and 31 females, with an age of (10.40±1.01) years and a spherical equivalent of (-2.88±0.42) D. There were 30 cases in the small correction zone group and 30 cases in the conventional group. There was no significant difference in uncorrected visual acuity and spherical equivalent between the two groups at each time point after treatment. The axial growth in the conventional group was (0.16±0.09) mm at 6 months after treatment, (0.28±0.17) mm at 12 months, and (0.37±0.20) mm at 18 months, whereas in the small treatment zone group it was (0.06±0.05) mm, (0.12±0.10) mm, and (0.18±0.14) mm, respectively. The myopia progression rate in the small treatment zone group was only 37.50%, 42.86%, and 48.64% of the conventional group at 6, 12, and 18 months, respectively. Corneal topography showed that the treatment area in the conventional group was (6.98±0.89) mm², while in the small treatment zone group it decreased by 23.2% [(5.36±0.73) mm²] (P<0.05). Correlation analysis revealed that the axial increase after 18 months of lens wearing was negatively correlated with the age before lens wearing (P<0.05), positively correlated with the corneal surface treatment zone size (P<0.05), and not correlated with the pupil diameter and spherical equivalent (all P>0.05). After the shaping treatment, the rate of adverse reaction, which was mild, in both groups was 10%, and the symptoms disappeared. Conclusion: Orthokeratology lenses with smaller treatment zones can significantly reduce the rate of axial length growth in children and adolescents compared to lenses with conventional treatment zones, without compromising treatment safety.


Asunto(s)
Miopía , Procedimientos de Ortoqueratología , Errores de Refracción , Masculino , Femenino , Humanos , Adolescente , Niño , Estudios Prospectivos , Miopía/prevención & control , Córnea , Topografía de la Córnea , Refracción Ocular
12.
Phys Rev Lett ; 129(2): 021803, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35867435

RESUMEN

Neutrino charged-current quasielastic-like scattering, a reaction category extensively used in neutrino oscillation measurements, probes nuclear effects that govern neutrino-nucleus interactions. This Letter reports the first measurement of the triple-differential cross section for ν_{µ} quasielastic-like reactions using the hydrocarbon medium of the MINERvA detector exposed to a wideband beam spanning 2≤E_{ν}≤20 GeV. The measurement maps the correlations among transverse and longitudinal muon momenta and summed proton kinetic energies, and compares them to predictions from a state-of-art simulation. Discrepancies are observed that likely reflect shortfalls with modeling of pion and nucleon intranuclear scattering and/or spectator nucleon ejection from struck nuclei. The separate determination of leptonic and hadronic variables can inform experimental approaches to neutrino-energy estimation.

13.
Biometrics ; 78(1): 24-34, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33616910

RESUMEN

Instrumental variables have been widely used to estimate the causal effect of a treatment on an outcome. Existing confidence intervals for causal effects based on instrumental variables assume that all of the putative instrumental variables are valid; a valid instrumental variable is a variable that affects the outcome only by affecting the treatment and is not related to unmeasured confounders. However, in practice, some of the putative instrumental variables are likely to be invalid. This paper presents two tools to conduct valid inference and tests in the presence of invalid instruments. First, we propose a simple and general approach to construct confidence intervals based on taking unions of well-known confidence intervals. Second, we propose a novel test for the null causal effect based on a collider bias. Our two proposals outperform traditional instrumental variable confidence intervals when invalid instruments are present and can also be used as a sensitivity analysis when there is concern that instrumental variables assumptions are violated. The new approach is applied to a Mendelian randomization study on the causal effect of low-density lipoprotein on globulin levels.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Sesgo , Causalidad
14.
IEEE Trans Inf Theory ; 68(9): 5975-6002, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36865503

RESUMEN

We study sparse group Lasso for high-dimensional double sparse linear regression, where the parameter of interest is simultaneously element-wise and group-wise sparse. This problem is an important instance of the simultaneously structured model - an actively studied topic in statistics and machine learning. In the noiseless case, matching upper and lower bounds on sample complexity are established for the exact recovery of sparse vectors and for stable estimation of approximately sparse vectors, respectively. In the noisy case, upper and matching minimax lower bounds for estimation error are obtained. We also consider the debiased sparse group Lasso and investigate its asymptotic property for the purpose of statistical inference. Finally, numerical studies are provided to support the theoretical results.

15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(2): 363-368, 2022 Apr 18.
Artículo en Zh | MEDLINE | ID: mdl-35435205

RESUMEN

OBJECTIVE: To discover the factors that may affect the use of selective tracheostomy among patients who have undergone head and neck surgeries with free flap reconstruction, so that the patients will not need tracheostomy nor receive the unnecessary treatment. METHODS: Five hundred and thirty-three patients who had undergone head and neck surgery with free flap reconstruction operated by the same team of surgery at Department of Oral and Maxillofacial Surgery at Peking University School of Stomatology from 2015 to 2016 were reviewed. Three hundred and twenty-one (60.2%) of these patients underwent selective tracheostomy. All the patients' demographic information, operation-related information, prior treatments, comorbidities and complications were recorded and analyzed. RESULTS: The patients with defects of the tongue, mouth floor, oropharynx and bilateral mandible, who underwent neck dissection and with previous radiotherapy and smoking habit were more likely to get selective tracheostomy. Usage of bulky soft tissue flap might also add to the risk of airway obstruction and the need of selective tracheostomy, while other factors were not significantly related to the risk of postoperative airway obstruction and the patients could be kept safe without selective tracheostomy. Most cases without tracheostomy were kept safe except one case, while 8.39% of the patients with tracheostomy suffered from tracheostomy related complications, mainly pneumonia and hemorrhage of the tracheostomy wound, yet none led to serious consequences or even death. CONCLUSION: Selective tracheostomy is not necessary for patients who have undergone head and neck surgeries with free flap reconstruction except that there are defects at the tongue, oropharynx and mandible. Neck dissection, bulky soft tissue flap reconstruction, previous radiotherapy and smoking habit may also add to the risk of postoperative airway obstruction, while a favorable decision would involve a combination of all the above factors to assure the safety of the postoperative airway for the patients undergone head and neck surgeries with free flap reconstruction.


Asunto(s)
Obstrucción de las Vías Aéreas , Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Procedimientos de Cirugía Plástica , Traqueostomía , Obstrucción de las Vías Aéreas/cirugía , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Procedimientos de Cirugía Plástica/efectos adversos , Estudios Retrospectivos
16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(4): 628-635, 2022 Aug 18.
Artículo en Zh | MEDLINE | ID: mdl-35950384

RESUMEN

OBJECTIVE: To investigate the expression of fibroblast growth factor receptor 2 (FGFR2) in clear cell renal cell carcinoma (ccRCC; or kidney renal clear cell carcinoma, KIRC), to analyze the relationship between the expression of FGFR2 and the clinical pathological features and prognosis of ccRCC, to study the relationship between the expression of FGFR2 and other molecules, and to explore its role in the development of ccRCC. METHODS: Gene expressional and clinical information of ccRCC patients were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus(GEO) database. Next, the data were transformed and collated. In the study, 104 clinical ccRCC samples and corresponding paracancerous normal tissue samples were collected from Department of Urology, Peking University First Hospital. Immunohistochemistry (IHC) was performed and the staining results were scored, so as to compare the expression of FGFR2 in ccRCC and paracancerous normal tissues. Besides, quantify real-time polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression level of FGFR2 in normal renal epithelial cell lines (293) and ccRCC cell lines (786-O, 769-P, OSRC-2, Caki-1, ACHN, and A498). In addition, the relationship between FGFR2 expression and clinical pathological characteristics (including TNM staging and pathological grading) and survival prognosis in ccRCC patients was further analyzed. Furthermore, the relationship between FGFR2 expression and B cells, T cells, natural killer (NK) cells and neutrophil infiltration in the ccRCC patients was analyzed, and the Biological General Repository for Interactionh Datasets (BioGRID) was used to builds protein-protein interaction (PPI) networks to study molecules that interacted with the FGFR2 protein. RESULTS: In the TCGA database, the expression of FGFR2 was down-regulated in ccRCC tissue samples compared with normal tissue samples, and the expression in the GEO database also showed this differences. Furthermore, FGFR2 expression was downregulated in ccRCC clinical samples and ccRCC cell lines, compared with corresponding paracancerous normal tissue or normal renal epithelial cell lines. In addition, FGFR2 high expression was associated with earlier, lower-level ccRCC and was associated with a better prognosis in the patients with ccRCC. Moreover, FGFR2 expression was not significantly related to B cells, T cells, NK cells and neutrophil infiltration, and the PPI network showed that FGFR2 protein interacted with certain molecules. CONCLUSION: Our work sheds light on the potential role of FGFR2 in the development of ccRCC, suggesting that FGFR2 may serve as a prognostic marker and potential therapeutic target for patients with ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Biomarcadores de Tumor/análisis , Carcinoma de Células Renales/patología , Humanos , Neoplasias Renales/patología , Pronóstico
17.
Zhonghua Wai Ke Za Zhi ; 60(6): 558-566, 2022 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-35658343

RESUMEN

Objective: To explore the effect of atlantoaxial fusion on the growth and development of children's cervical spine. Methods: The clinical data of 12 children with atlantoaxial dislocation who underwent posterior atlantoaxial fusion at Department of Orthopaedics,the 909th Hospital of Joint Logistics Support Force of Chinese People's Liberation Army from June 2002 to September 2013 were retrospective analyzed. There were 7 males and 5 females,with age of (8.1±3.1)years (range:3 to 13 years).Nine cases were traumatic and 3 cases were congenital malformations,1 of the children had Down syndrome. All children underwent posterior atlantoaxial fusion. Furthermore,the information of the height and anteroposterior width of the cervical vertebral bodies and vertical growth rate of the fusion mass were collected from all patients immediately postoperatively and during the follow-up.The range of motion in cervical spine were collected preoperatively and during follow-up period. Data were compared using independent sample t test, paired sample t test and repeated-measurement. Results: All 12 children had regular follow-up within (122.4±25.3)months(range:65 to 163 months). The height and anteroposterior width of the cervical vertebral bodies were similar to these results with those in published reports of growth in normal children of the same age(all P<0.01). At the last follow-up,atlantoaxial fusion of 11 cases had substantial growth (vertical growth rate of the fusion mass:11 cases ≥10%, 1 case <10%);the range of motion in cervical spine was close to the normal level (flexion(55.2±5.0)°,extension (65.3±4.9)°,left bending (41.7±4.5)°,right bending (42.4±4.4)°,left rotation (66.4±5.6)°,right rotation (68.5±5.8)°). Conclusions: Atlantoaxial fusion surgery is satisfactory in the treatment of pediatric atlantoaxial dislocation.During the follow-up,the growth and development of the cervical spine is close to that of normal children of the same age.In long-term observation,it has been found that the operation has no negative effect on the growth and development of the children's cervical spine.


Asunto(s)
Articulación Atlantoaxoidea , Luxaciones Articulares , Fusión Vertebral , Articulación Atlantoaxoidea/anomalías , Articulación Atlantoaxoidea/cirugía , Vértebras Cervicales/cirugía , Niño , Anomalías Congénitas , Femenino , Crecimiento y Desarrollo , Humanos , Luxaciones Articulares/cirugía , Masculino , Estudios Retrospectivos , Fusión Vertebral/métodos , Resultado del Tratamiento
18.
Phys Rev Lett ; 127(6): 060505, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34420337

RESUMEN

Cross-resonance (CR) gates have emerged as a promising scheme for fault-tolerant quantum computation with fixed-frequency qubits. We experimentally implement an entangling CR gate by using a microwave-only control in a tunable coupling superconducting circuit, where the tunable coupler provides extra degrees of freedom to verify optimal conditions for constructing a CR gate. By developing a three-qubit Hamiltonian tomography protocol, we systematically investigate the dependency of gate fidelities on spurious qubit interactions and present the first experimental approach to the evaluation of the perturbation impact arising from spectator qubits. Our results reveal that the spectator qubits lead to reductions in CR gate fidelity dependent on ZZ interactions and particular frequency detunings between spectator and gate qubits. The target spectator demonstrates a more serious impact than the control spectator under a standard echo pulse scheme, whereas the degradation of gate fidelity is observed up to 22.5% as both the spectators are present with a modest ZZ coupling to the computational qubits. Our experiments uncover an optimal CR operation regime, and the method we develop here can readily be applied to improving other kinds of two-qubit gates in large-scale quantum circuits.

19.
J Struct Biol ; 212(1): 107584, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32736074

RESUMEN

It is shown how serial block-face electron microscopy (SBEM) of insulin-secreting ß-cells in wild-type mouse pancreatic islets of Langerhans can be used to determine maturation times of secretory granules. Although SBEM captures the ß-cell structure at a snapshot in time, the observed ultrastructure can be considered representative of a dynamic equilibrium state of the cells since the pancreatic islets are maintained in culture in approximate homeostasis. It was found that 7.2 ± 1.2% (±st. dev.) of the ß-cell volume is composed of secretory granule dense-cores exhibiting angular shapes surrounded by wide (typically ≳100 nm) electron-lucent halos. These organelles are identified as mature granules that store insulin for regulated release through the plasma membrane, with a release time of 96 ± 12 h, as previously obtained from pulsed 35S-radiolabeling of cysteine and methionine. Analysis of ß-cell 3D volumes reveals a subpopulation of secretory organelles without electron-lucent halos, identified as immature secretory granules. Another subpopulation of secretory granules is found with thin (typically ≲30 nm) electron-lucent halos, which are attributed to immature granules that are transforming from proinsulin to insulin by action of prohormone convertases. From the volume ratio of proinsulin in the immature granules to insulin in the mature granules, we estimate that the newly formed immature granules remain in morphologically-defined immature states for an average time of 135 ± 14 min, and the immature transforming granules for an average time of 130 ± 17 min.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Vesículas Secretoras/metabolismo , Animales , Transporte Biológico/fisiología , Membrana Celular/metabolismo , Gránulos Citoplasmáticos/metabolismo , Insulina/metabolismo , Masculino , Ratones , Microscopía Electrónica/métodos
20.
Phys Rev Lett ; 124(12): 121801, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32281855

RESUMEN

We measure neutrino charged-current quasielasticlike scattering on hydrocarbon at high statistics using the wideband Neutrinos at the Main Injector beam with neutrino energy peaked at 6 GeV. The double-differential cross section is reported in terms of muon longitudinal (p_{∥}) and transverse (p_{⊥}) momentum. Cross section contours versus lepton momentum components are approximately described by a conventional generator-based simulation, however, discrepancies are observed for transverse momenta above 0.5 GeV/c for longitudinal momentum ranges 3-5 and 9-20 GeV/c. The single differential cross section versus momentum transfer squared (dσ/dQ_{QE}^{2}) is measured over a four-decade range of Q^{2} that extends to 10 GeV^{2}. The cross section turnover and falloff in the Q^{2} range 0.3-10 GeV^{2} is not fully reproduced by generator predictions that rely on dipole form factors. Our measurement probes the axial-vector content of the hadronic current and complements the electromagnetic form factor data obtained using electron-nucleon elastic scattering. These results help oscillation experiments because they probe the importance of various correlations and final-state interaction effects within the nucleus, which have different effects on the visible energy in detectors.

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