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1.
Sci Total Environ ; 927: 172386, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604360

RESUMO

Fiber film have received widespread attention due to its green friendliness. We can use microorganisms to degrade lignin in straw to obtain cellulose and make fiber films. Herein, a group of high-temperature (50 °C) lignin degrading bacterial consortium (LDH) was enriched and culture conditions for lignin degradation were optimized. Combined with high-throughput sequencing technology, the synergistic effect of LDH-composited bacteria was analyzed. Then LDH was used to treat rice straw for the bio-pulping experiment. The results showed that the lignin of rice straw was degraded 32.4 % by LDH at 50 °C for 10 d, and after the optimization of culture conditions, lignin degradation rate increased by 9.05 % (P < 0.001). The bacteria that compose in LDH can synergistically degrade lignin. Paenibacillus can encode all lignin-degrading enzymes present in the LDH. Preliminary tests of LDH in the pulping industry have been completed. This study is the first to use high temperature lignin degrading bacteria to fabricate fiber film.


Assuntos
Lignina , Oryza , Lignina/metabolismo , Biodegradação Ambiental , Consórcios Microbianos/fisiologia , Bactérias/metabolismo , Celulose/metabolismo
2.
Front Bioeng Biotechnol ; 11: 1286993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38130819

RESUMO

Objective: The treatment for posterolateral tibial plateau fractures (PTPF) have been subjects of controversy. We conducted a study to improve the fixation of PTPF through a lateral approach. Methods: We utilized 40 synthetic tibias and categorized the fracture models into five groups based on the locking compression plate (LCP) and T-distal radius plate (TPP) via various forms of fixation with screws through the posterolateral (PL) fracture fragments. I: Two-screw fixation using two locking screws (LPTL). Ⅱ: Two-screw fixation with both variable angle locking screws (LPTV). Ⅲ: One-screw fixation with one locking screw (LPOL). Ⅳ: One-screw fixation with one locking screw and two anteroposterior lag screws (LPOLTL). Ⅴ: a distal radius plate with three locking screws (TPP). Biomechanical tests were conducted to observe the axial compression displacement of the PL fracture fragments at force levels of 250 N, 500 N, and 750 N, as well as to determine the failure load and the axial stiffness for each respective group. Results: Under a 750 N load condition, the displacements within the five experimental groups exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. However, there were no significant differences between Group V and Group II, Group I and Group IV (p > 0.05), and only Group Ⅲ demonstrated a displacement exceeding 3 mm. The failure load and the axial stiffness exhibited the same trend. Conversely, statistical significance was identified among the remaining group compared with Group Ⅲ (p < 0.05). Regarding the finite element analysis, the maximum displacements for the five models under the load of 750 N exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. The following trends were observed in maximum von Mises stresses for these models under the load of 750 N: Ⅴ < Ⅱ < Ⅳ< Ⅰ < Ⅲ. Conclusion: It is crucial to address the inadequate mechanical strength associated with single screw fixation of LCP for fixing PL fractures in a clinical setting. The biomechanical strength of two-screw fixation surpasses that of single-screw fixation. Introducing variable-angle screws can further enhance the fixation range. Furthermore, the addition of two lag screws threaded from anterior to posterior can compensate the mechanical stability, when PL fracture is fixed with single screw in clinic.

3.
BMC Musculoskelet Disord ; 24(1): 625, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532980

RESUMO

BACKGROUND: The risks associated with deep vein thrombosis (DVT) have gained significant recognition over time. A prevalent form of distal DVT is isolated calf muscular venous thrombosis (ICMVT). Despite its common clinical occurrence, data on ICMVT subsequent to tibial plateau fracture (TPF) surgery are scarce. This study aimed to examine the epidemiological characteristics and associated risk factors (RFs) of ICMVT following TPF surgery. METHODS: For this retrospective analysis, we included patients from our hospital, who underwent TPF surgery between March 2017 and March 2021. Patients' electronic medical records were reviewed, including admission details, fracture classification, surgical procedures, and laboratory biomarkers. The HSS (The American Hospital for Special Surgery) and Rasmussen scores were employed to evaluate the clinical effect. A Color Duplex Flow Imager (CDFI) was regularly used to detect pre- and postoperative venous thrombosis in the lower limbs. Finally, uni- and multivariate logistic regression analyses were used to identify independent RFs associated with ICMVT. RESULTS: Overall, 481 participants were recruited for analysis. Postoperative ICMVT occurred in 47 patients. All ICMVTs occurred on the affected side. Four of the 47 ICMVT patients exhibited sudden postoperative swelling in the affected limb. The HSS and Rasmussen scores in the non-ICMVT cohort (87.6 ± 8.2, 16.0 ± 1.7) were markedly different from the ICMVT cohort (84.8 ± 8.2, 15.5 ± 1.6) (p = 0.014, p = 0.031). This study finally identified five postoperative ICMVT-related RFs, which were age (> 55 years old) (OR 3.06; 95% CI 1.47-6.37; p = 0.003), gender (female) (OR 2.67; 95% CI 1.37-5.22; p = 0.004), surgical duration (> 114 min) (OR 3.14; 95% CI 1.44-6.85; p = 0.004), elevated white blood cell content (OR 2.85; 95% CI 1.47-5.51; p = 0.002), and hyponatremia (OR 2.31; 95% CI 1.04-5.12; p = 0.040). CONCLUSION: The epidemiological findings of this study may help predict ICMVT risk after surgery thus facilitating the development of individualized clinical assessments and targeted prevention programs.


Assuntos
Trombose , Fraturas da Tíbia , Fraturas do Planalto Tibial , Trombose Venosa , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Incidência , Perna (Membro) , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia , Fatores de Risco , Fraturas da Tíbia/epidemiologia , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/complicações
4.
Neurobiol Aging ; 102: 220.e1-220.e4, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33663879

RESUMO

Fabry disease (FD) is an important underlying condition in young cryptogenic stroke patients and has also been implicated in cerebral small vessel disease. However, the contributions of causative GLA mutations in patients with intracerebral hemorrhage (ICH) remain unclear. In this study, GLA sequences were analyzed in a Chinese ICH cohort comprising 373 patients with computed tomography-confirmed ICH and 563 in-house controls and East Asians from public databases. Only one previously reported mutation, p. Ala15Val, responsible for Fabry disease was identified in a female patient with nonlobar ICH. Therefore, this definitive GLA mutation accounted for 0.27% (1/373) of Chinese patients with ICH. Another functional variant, rs2071225 (c.-10C>T), was present at minor allele frequency (MAF) of 9.1%, indicating no association with ICH, despite a trend of an association for male patients with lobar ICH. In conclusion, our results indicate that the GLA mutation is an uncommon genetic etiology of ICH in China.


Assuntos
Análise Mutacional de DNA , Estudos de Associação Genética , Acidente Vascular Cerebral Hemorrágico/genética , Mutação , alfa-Galactosidase/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Estudos de Coortes , Doença de Fabry/genética , Feminino , Frequência do Gene , Acidente Vascular Cerebral Hemorrágico/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
Nano Lett ; 11(10): 4256-60, 2011 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-21882819

RESUMO

Realization of smaller and faster coherent light sources is critically important for the emerging applications in nanophotonics and information technology. Semiconductor lasers are arguably the most suitable candidate for such purposes. However, the minimum size of conventional semiconductor lasers utilizing dielectric optical cavities for sustaining laser oscillation is ultimately governed by the diffraction limit (∼(λ/2n)(3) for three-dimensional (3D) cavities, where λ is the free-space wavelength and n is the refractive index). Here, we demonstrate the 3D subdiffraction-limited laser operation in the green spectral region based on a metal-oxide-semiconductor (MOS) structure, comprising a bundle of green-emitting InGaN/GaN nanorods strongly coupled to a gold plate through a SiO(2) dielectric nanogap layer. In this plasmonic nanocavity structure, the analogue of MOS-type "nanocapacitor" in nanoelectronics leads to the confinement of the plasmonic field into a 3D mode volume of 8.0 × 10(-4) µm(3) (∼0.14(λ/2n)(3)).

6.
Opt Express ; 17(20): 17227-33, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19907509

RESUMO

We report intense green photoluminescence (PL) from vertically aligned indium gallium nitride (InxGa(1-x)N) nanorod arrays. The formation of InxGa(1-x)N/GaN-heterostructure nanorods increases the localization depth of the radially confined carriers (> 100 meV). Temperature dependent PL peak energy of InGaN nanorods shows the characteristic S-shaped behavior, indicating the prominent carrier trapping in band-tail states associated with the nonuniformity of In content. Time-resolved PL (TRPL) response decays biexponentially and the dominant slow decay component of TRPL for InxGa(1-x)N nanorods is due to the transfer of excitons to the localized states before the radiative decay.


Assuntos
Gálio/química , Índio/química , Iluminação/métodos , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Nanotubos/química , Nanotubos/ultraestrutura , Cor , Teste de Materiais
7.
Opt Express ; 16(11): 8106-16, 2008 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-18545523

RESUMO

Vertically aligned gallium nitride (GaN) nanorod arrays grown by the catalyst-free, self-organized method based on plasma-assisted molecular-beam epitaxy are shown to behave as subwavelength optical media with low effective refractive indices. In the reflection spectra measured in the entire visible spectral region, strong reflectivity modulations are observed for all nanorod arrays, which are attributed to the effects of Fabry-Pérot microcavities formed within the nanorod arrays by the optically flat air/nanorods and nanorods/substrate interfaces. By analyzing the reflectivity interference fringes, we can quantitatively determine the refractive indices of GaN nanorod arrays as functions of light wavelength. We also propose a model for understanding the optical properties of GaN nanorod arrays in the transparent region. Using this model, good numerical fitting can be achieved for the reflectivity spectra.


Assuntos
Desenho Assistido por Computador , Tecnologia de Fibra Óptica/instrumentação , Gálio/química , Interferometria/instrumentação , Modelos Teóricos , Nanotubos/química , Nanotubos/ultraestrutura , Refratometria/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Nanotubos/efeitos da radiação , Refratometria/métodos
8.
Psychiatry Clin Neurosci ; 60(5): 626-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16958948

RESUMO

Usher syndrome is a heterogeneous autosomal recessive disorder characterized by hearing and visual sensory impairment. Retinitis pigmentosa is essential for its diagnosis. There are only a few reports describing patients with Usher syndrome presenting with psychotic features and the etiology of its psychiatric manifestation is still unknown. Herein, the authors report variable congenital hearing impairment and progressive visual loss occurring in five of seven family members and two of them meeting the diagnostic criteria of Usher syndrome with psychotic features. Furthermore, the authors compare their psychiatric symptoms with other reports and the possible etiologies of psychotic symptoms are discussed.


Assuntos
Transtornos Psicóticos/psicologia , Síndromes de Usher/psicologia , Adulto , Agressão , Alcoolismo/psicologia , Feminino , Humanos , Masculino , Linhagem , Transtornos Psicóticos/etiologia , Esquizofrenia/etiologia , Psicologia do Esquizofrênico , Tomografia Computadorizada por Raios X , Síndromes de Usher/complicações
9.
Dev Dyn ; 233(2): 584-94, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15778968

RESUMO

The retinoic acid receptor RARbeta is highly expressed in the striatum of the ventral telencephalon. We studied the expression pattern of different RARbeta isoforms in the developing mouse striatum by in situ hybridization. We found a differential ontogeny of RARbeta2 and RARbeta1/3 in embryonic day (E) 13.5 lateral ganglionic eminence (striatal primordium). RARbeta2 mRNA was detected primarily in the rostral and ventromedial domains, whereas RARbeta1/3 mRNAs were enriched in the caudal and dorsolateral domains. Notably, by E16.5, a prominent decreasing gradient of RARbeta2 mRNA was present in the developing striatum along the rostrocaudal axis, i.e., RARbeta2 was expressed at higher levels in the rostral than the caudal striatum. No such gradient was found for RARbeta1/3 and RARbeta3 mRNAs. The rostrocaudal RARbeta2 gradient gradually disappeared postnatally and was absent in the adult striatum. The differential expression pattern of RARbeta isoforms in the developing striatum may provide an anatomical basis for differential gene regulation by RARbeta signaling.


Assuntos
Vértebra Cervical Áxis/embriologia , Vértebra Cervical Áxis/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Receptores do Ácido Retinoico/genética , Animais , Vértebra Cervical Áxis/crescimento & desenvolvimento , DNA Complementar/genética , Hibridização In Situ , Camundongos , Neostriado/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/metabolismo
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