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1.
Nano Lett ; 24(4): 1406-1414, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38227806

RESUMO

The realization of high-Q single-mode lasing on the microscale is significant for the advancement of on-chip integrated light sources. It remains a challenging trade-off between Q-factor enhancement and light-field localization to raise the lasing emission rate. Here, we fabricated a zero-dimensional perovskite microcavity integrated with a nondamage pressed microlens to three-dimensionally tailor the intracavity light field and demonstrated linearly and nonlinearly (two-photon) pumped lasing by this microfocusing configuration. Notably, the microlensing microcavity experimentally achieves a high Q-factor (16700), high polarization (99.6%), and high Purcell factor (11.40) single-mode lasing under high-repetition pulse pumping. Three-dimensional light-field confinement formed by the microlens and plate microcavity simultaneously reduces the mode volume (∼3.66 µm3) and suppresses diffraction and transverse walk-off loss, which induces discretization on energy-momentum dispersions and spatial electromagnetic-field distributions. The Q factor and Purcell factor of our lasing come out on top among most of the reported perovskite microcavities, paving a promising avenue toward further studying electrically driven on-chip microlasers.

2.
Appl Opt ; 63(2): 322-326, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38227224

RESUMO

In this work, a detailed study was conducted of the temperature and excitation wavelength-dependent photoluminescence (PL) spectra of the chromium-doped yttrium aluminum garnet (Cr:YAG) transparent ceramic. Focusing on the two sets of zero-phonon lines (ZPLs) of the 2 E→4 A 2 transition in this material, the PL spectra are discovered to evolve significantly with respect to temperature and be highly dependent on the excitation wavelength. Compared to the continuous variation behavior with temperature, an increase in the excitation wavelength leads to a blueshift of the peak position within the regions of 450 nm to 465 nm, 465 nm to 490 nm, and 490 nm to 500 nm, and a sharp change in the PL position at the excitation wavelengths of 465 nm and 490 nm. The electron-phonon coupling (EPC) effect is believed to be more sensitive to the excitation wavelength. Different excitation wavelengths involve different electronic levels participating in the light emission processes, which explains the evolution behavior of the PL peak position with respect to the excitation wavelength. Moreover, the emergence of weak peaks next to the ZPLs at particular temperatures and excitation wavelengths is also observed. This work compares the influence of the temperature and excitation wavelength to the PL properties of the Cr:YAG transparent ceramic, which promotes an advanced understanding of the luminescence behavior of the Cr:YAG transparent ceramics.

3.
BMC Pulm Med ; 24(1): 365, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075451

RESUMO

OBJECTIVE: This study aims to investigate the prognostic significance of inflammatory cytokines and lymphocyte levels in predicting disease progression among patients with COVID-19 infection. METHODS: Ninety-two hospitalized COVID-19 patients were retrospectively included as subjects for this study. General clinical information and various indicators, including lymphocyte count, interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), tumor necrosis factor (TNF), were collected. All patients received treatment according to the ninth edition of the guidelines for COVID-19. Incidences of endotracheal intubation and mortality within 28 days were observed. RESULTS: 1.In the analysis of intubation impact, multivariate analysis identified age, immunoglobulins, lymphocytes, and IL-6 as independent risk factors. When analyzing the impact on patient mortality, multivariate analysis revealed age, prealbumin, and BNP as independent risk factors. 2. Lymphocyte count and inflammatory factors demonstrated predictive value for endotracheal intubation in COVID-19 patients. The critical lymphocyte count value was 0.91, with a sensitivity of 38.8%, specificity of 92.9%, and AUC of 0.687 (95% CI: 0.580-0.795). The critical IL-6 value was 38.21, with a sensitivity of 81%, specificity of 63.3%, and AUC of 0.771 (95% CI: 0.6670.872). The area under the ROC curve for IL-8, IL-10 and TNF is 0.665, 0.712 and 0.648, respectively. 3.Lymphocyte count and inflammatory factors also exhibited predictive value for death in COVID-19 patients. The critical lymphocyte count value was 0.56, with a sensitivity of 71.2%, specificity of 57.5%, and AUC of 0.641 (95% CI: 0.528-0.754). The critical IL-6 value was 53.05, with a sensitivity of 75%, specificity of 71.2%, and AUC of 0.770 (95% CI: 0.6690.870). The area under the ROC curve for IL-8, IL-10 and TNF is 0.687, 0.683 and 0.636, respectively. CONCLUSION: Elevated inflammatory factors and decreased lymphocyte levels have prognostic value for predicting endotracheal intubation and mortality in COVID-19 patients, providing valuable insights for clinicians in anticipating disease progression.


Assuntos
COVID-19 , Intubação Intratraqueal , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/terapia , COVID-19/sangue , COVID-19/complicações , COVID-19/diagnóstico , Masculino , Feminino , Contagem de Linfócitos , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Prognóstico , Valor Preditivo dos Testes , Citocinas/sangue , Fatores de Risco , Interleucina-10/sangue , Interleucina-6/sangue , Progressão da Doença , Idoso de 80 Anos ou mais , Curva ROC
4.
Waste Manag Res ; : 734242X241241602, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563513

RESUMO

The development of the solar market has been fast in the past decades, and the number of photovoltaic module installations is large. The photovoltaic modules have a lifetime of about 25 years and need recovery after that. The aluminium-back surface field (Al-BSF) module is the first kind of large-scale installed module and will come to its end of life in the next few years. The recycling of silicon material in the Al-BSF module is investigated in this work. The components of the module are separated, and the silicon material in the module is collected and then purified by (aluminium-silicon) Al-Si solvent refining for reuse. It is found that Al-Si solvent refining removed key impurity elements, namely boron and phosphorus, in the collected silicon. Kinetics has a great effect on boron and phosphorus removal, and boron and phosphorus contents in purified silicon decrease with decreasing cooling rate. The boron and phosphorus contents in silicon are lowered to 0.28 and 0.03 ppmw, respectively, after two times of Al-Si solvent refining with the cooling rate of 5.55 * 10-4 K second-1, and it meets the requirement of solar-grade silicon.

5.
Pak J Med Sci ; 40(9): 2085-2089, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39416641

RESUMO

Objective: To investigate the clinical efficacy of 3D-printed fusion cage implantation in treating cervical spondylotic myelopathy. Methods: A retrospective analysis was performed on 52 patients with single-segment cervical spondylotic myelopathy who received anterior cervical discectomy and fusion in Affiliated Hospital of Beihua University from July 2019 to July 2022. They were divided into the 3D group and the control group. Afterward, the perioperative indicators were compared between the two groups. Meanwhile, the Japanese Orthopaedic Association (JOA) scores, Visual analogue scale (VAS) and neck disability index (NDI) were recorded pre-operation and one-year post-operation. Evaluate the fusion rate of two group of intervertebral fusion cages. Results: The JOA score and NDI of the two groups of patients were significantly improved compared to pre-operation(P<0.05), and the JOA score, JOA score improvement rate, and NDI of the 3D group were better than the control group (P<0.05), the VAS scores were significantly improved compared to pre-operation(P<0.05), but there was no statistically significant difference between the groups (p >0.05). The intervertebral height, angle, and cervical Cobb angle of the two groups of patients were significantly improved compared to pre-operation (P<0.05), and the improvement of intervertebral height, angle, and cervical Cobb angle in the 3D group was better than the control group(P<0.05). Conclusion: The clinical efficacy of 3D printed intervertebral fusion cage placement in the treatment of cervical spondylotic myelopathy may be reliable, and it would be better than traditional intervertebral fusion cages in maintaining the height, angle, cervical Cobb angle, and fusion rate of the intervertebral space.

6.
Pak J Med Sci ; 40(4): 648-651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545002

RESUMO

Objective: To explore the safety and efficacy of metastatic osteosarcoma treatment with combined sintilimab injection and chemotherapy. Methods: We performed a retrospective analysis of 32 patients with metastatic osteosarcoma admitted to the Affiliated Hospital of Beihua University between January 2019 and June 2020. The sample was divided into an observation group, treated with sintilimab injection combined with chemotherapy (n= 16) and a control group, treated with chemotherapy (n = 16). Clinical efficacy and adverse reactions were compared between the two groups. Results: The overall response rates were 68.75% in the observation group and 31.25% in the control group (p < 0.05). The incidences of adverse reactions were 56.25% in the observation group and 81.25% in the control group. This was not a significant difference. In the observation group, the progression-free survival time was 8.13 ± 2.50 months, and the overall survival time was 22.75 ± 4.95 months. These were both significantly longer than the respective 6.44 ± 1.93 months and 19.69 ± 2.68 months in the control group (p < 0.05). Conclusion: The treatment of metastatic osteosarcoma with combined sintilimab injection and chemotherapy was found to prolong progression-free survival and overall survival time without increasing the incidence of adverse reactions.

7.
BMC Musculoskelet Disord ; 24(1): 99, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750859

RESUMO

OBJECTIVE: A combination of lateral soft tissue release, medial soft tissue contraction, vastus medialis anterior placement, medial patellofemoral ligament reconstruction, and rectus femoris insertion reconstruction are introduced in the treatment of habitual patellar dislocation in adolescents. METHODS: A retrospective analysis was performed on 12 patients (17 knees) with habitual patellar dislocation and unclosed epiphyses who underwent surgical treatment at the First Hospital of Jilin University from May 2017 to November 2021. The Lysholm scores and Q angle were collected preoperatively and at final follow-up and were compared. RESULTS: Twelve patients (4 boys and 8 girls) aged 10-15 years were retrospectively analysed, who followed up for an average of 21 months (5-48 months). The range of motion of the knee joint returned to normal in all patients, and no cases of complications including surgical site infection, joint stiffness, or patellar re-dislocation occurred. The mean Lysholm scores and Q angles improved from 73.9, and 19.6° preoperatively to 91.7, and 13.9° at the final follow-up, respectively. CONCLUSION: The preliminary effect of the combination surgery for habitual patellar dislocation in adolescents was satisfactory.


Assuntos
Luxação Patelar , Articulação Patelofemoral , Procedimentos de Cirurgia Plástica , Masculino , Feminino , Humanos , Adolescente , Luxação Patelar/cirurgia , Estudos Retrospectivos , Articulação do Joelho/cirurgia , Ligamentos Articulares/cirurgia , Articulação Patelofemoral/cirurgia
8.
Microb Pathog ; 104: 217-224, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28104383

RESUMO

Urinary tract infections (UTIs) are among the most common human diseases worldwide. This study aimed to collect uropathogenic Escherichia coli (UPEC) isolates from Jiangsu Province and obtain insights into the molecular epidemiology of UPEC in this region. The O serotypes, phylogenetic groups, and virulence factors of 183 UPEC isolates were determined. In this study, we isolated 51 UPEC isolates with common O serotypes including O1, O2, O4, O6, O7, O16, O18 and O75, as well as 35 of those with uncommonly encountered O serotypes including O8, O12, O15, O26, and O74. Groups B2 and D were the most prevalent phylogenetic groups and accounted for 29.5% and 41% of the isolates, respectively. In the tested 13 virulence genes (VGs), tonB and dsdA possessed the highest prevalence rate, followed by fimH, degP and ompR. Several other virulence genes such as fliC, neuC, ireA, and vat had prevalence less than 23%. Moreover, representative isolates belonging to common or uncommon O serotypes with different numbers of VGs were chosen for the pathogenic analyses. Based on the results of 1-day-old chick lethality assay and UTI ascending mouse infection model, our study suggested that the virulence of UPEC isolates for chicks and/or mice depended on both the number of VGs expressed and the O serotypes.


Assuntos
Infecções por Escherichia coli/microbiologia , Genótipo , Antígenos O/análise , Sorogrupo , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/classificação , Fatores de Virulência/análise , Animais , Animais Recém-Nascidos , Galinhas , China , Modelos Animais de Doenças , Infecções por Escherichia coli/epidemiologia , Humanos , Camundongos Endogâmicos BALB C , Epidemiologia Molecular , Filogenia , Análise de Sobrevida , Infecções Urinárias/epidemiologia , Escherichia coli Uropatogênica/genética , Escherichia coli Uropatogênica/isolamento & purificação , Escherichia coli Uropatogênica/patogenicidade , Fatores de Virulência/genética
9.
Tumour Biol ; 37(5): 6447-55, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26631042

RESUMO

Increasing evidence indicates that microRNAs (miRNAs) play critical roles in osteosarcoma (OS) occurrence and development. MicroRNA-874 (miR-874) has proven to be dysregulated in several human cancers. However, the biological function and underlying molecular mechanism of miR-874 in OS remain unclear. In this study, we aimed to investigate the biological role and potential mechanism of miR-874 in OS. Here, we found that miR-874 expression was significantly decreased in OS cell lines and tissues by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), and its expression was correlated with tumor-node-metastasis (TNM) stage, tumor size, and lymph node metastasis (all P < 0.01). Functional study revealed that overexpression of miR-874 in OS cells could remarkably inhibit proliferation, migration, and invasion and induce cell apoptosis. In addition, E2F transcription factor 3 (E2F3) was confirmed as a target of miR-874 in OS cells. E2F3 mRNA expression was upregulated and was inversely correlated with the level of miR-874 in OS tissues. Importantly, downregulation of E2F3 mimicked the effect of overexpression miR-874 in OS cells, and E2F3 overexpression partially attenuated the tumor-suppressive effects of miR-874 in OS cells. Taken together, these findings suggested that miR-874 might suppress the growth and metastasis of OS cells partially by targeting E2F3.


Assuntos
Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Fator de Transcrição E2F3/genética , MicroRNAs/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Interferência de RNA , Regiões 3' não Traduzidas , Adulto , Idoso , Apoptose/genética , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Carga Tumoral
10.
J Insect Sci ; 14: 195, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25434030

RESUMO

Basic helix-loop-helix (bHLH) proteins comprise a large superfamily of transcription factors, which are involved in the regulation of various developmental processes. bHLH family members are widely distributed in various eukaryotes including yeast, fruit fly, zebrafish, mouse, and human. In this study, we identified 55 bHLH motifs encoded in genome sequence of the human body louse, Pediculus humanus corporis (Phthiraptera: Pediculidae). Phylogenetic analyses of the identified P. humanus corporis bHLH (PhcbHLH) motifs revealed that there are 23, 11, 9, 1, 10, and 1 member(s) in groups A, B, C, D, E, and F, respectively. Examination to GenBank annotations of the 55 PhcbHLH members indicated that 29 PhcbHLH proteins were annotated in consistence with our analytical result, 8 were annotated different with our analytical result, 12 were merely annotated as hypothetical protein, and the rest 6 were not deposited in GenBank. A comparison on insect bHLH gene composition revealed that human body louse possibly has more hairy and E(spl) genes than other insect species. Because hairy and E(spl) genes have been found to negatively regulate the differentiation of insect preneural cells, it is suggested that the existence of additional hairy and E(spl) genes in human body louse is probably the consequence of its long period adaptation to the relatively dark and stable environment. These data provide good references for further studies on regulatory functions of bHLH proteins in the growth and development of human body louse.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sequências Hélice-Alça-Hélice , Proteínas de Insetos/genética , Pediculus/genética , Sequência de Aminoácidos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Pediculus/metabolismo , Filogenia
11.
J Phys Chem Lett ; : 11015-11021, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39466238

RESUMO

Anomalous thermal behaviors of excitonic luminescence in CsPbBr3 perovskite quantum dots (PQDs) were observed. It is found that the main luminescence peak originated from the excitonic radiative recombination assisted by the longitudinal-optical (LO) phonon, and its integrated intensity first declines as the temperature varies from 10 to 150 K and then turns to increase at ∼160 K, reaching a maximum value at 300 K. A model considering the thermal detrapping and transfer of electrons from a trap level is developed to interpret these abnormal thermal behaviors of the luminescence from the PQDs. On the other hand, the quantum-mechanical multimode Brownian oscillator model was employed to unravel that the Huang-Rhys factor exclusively characterizing the exciton-phonon coupling in the studied CsPbBr3 PQDs decreases from 1.65 at 10 K to 1.31 at 200 K.

12.
J Bacteriol ; 195(11): 2474-80, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23504015

RESUMO

Avian pathogenic Escherichia coli (APEC) infection causes avian colibacillosis, which refers to any localized or systemic infection, such as acute fatal septicemia or subacute pericarditis and airsacculitis. The RfaH transcriptional regulator in E. coli is known to regulate a number of phenotypic traits. The direct effect of RfaH on the virulence of APEC has not been investigated yet. Our results showed that the inactivation of rfaH significantly decreased the virulence of APEC E058. The attenuation was assessed by in vivo and in vitro assays, including chicken infection assays, an ingestion and intracellular survival assay, and a bactericidal assay with serum complement. The virulence phenotype was restored to resemble that of the wild type by complementation of the rfaH gene in trans. The results of the quantitative real-time reverse transcription-PCR (qRT-PCR) analysis and animal system infection experiments indicated that the deletion of rfaH correlated with decreased virulence of the APEC E058 strain.


Assuntos
Galinhas , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fatores de Alongamento de Peptídeos/genética , Doenças das Aves Domésticas/microbiologia , Transativadores/genética , Animais , Coinfecção , Primers do DNA/genética , Resistência à Doença , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/patogenicidade , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Teste de Complementação Genética , Macrófagos/microbiologia , Fatores de Alongamento de Peptídeos/metabolismo , Fenótipo , Doenças das Aves Domésticas/imunologia , Deleção de Sequência , Organismos Livres de Patógenos Específicos , Transativadores/metabolismo , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
13.
Mol Genet Genomics ; 288(7-8): 365-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23756994

RESUMO

Helix-loop-helix (bHLH) proteins play essential regulatory roles in a variety of biological processes. These highly conserved proteins form a large transcription factor superfamily, and are commonly identified in large numbers within animal, plant, and fungal genomes. The bHLH domain has been well studied in many animal species, but has not yet been characterized in non-avian reptiles. In this study, we identified 102 putative bHLH genes in the genome of the green anole lizard, Anolis carolinensis. Based on phylogenetic analysis, these genes were classified into 43 families, with 43, 24, 16, 3, 10, and 3 members assigned into groups A, B, C, D, E, and F, respectively, and 3 members categorized as "orphans". Within-group evolutionary relationships inferred from the phylogenetic analysis were consistent with highly conserved patterns observed for introns and additional domains. Results from phylogenetic analysis of the H/E(spl) family suggest that genome and tandem gene duplications have contributed to this family's expansion. Our classification and evolutionary analysis has provided insights into the evolutionary diversification of animal bHLH genes, and should aid future studies on bHLH protein regulation of key growth and developmental processes.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/classificação , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Evolução Molecular , Lagartos/genética , Família Multigênica , Motivos de Aminoácidos , Animais , Biologia Computacional/métodos , Sequência Conservada , Éxons , Genoma , Sequências Hélice-Alça-Hélice , Íntrons , Camundongos , Fases de Leitura Aberta , Filogenia , Matrizes de Pontuação de Posição Específica
14.
J Phys Chem Lett ; 14(28): 6464-6469, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37436159

RESUMO

In this paper, the giant tunability of thermal behaviors, i.e., from thermal deterioration to substantial growth, is firmly demonstrated for the vibronic luminescence of Mn4+ ions in fluoride phosphors. Such peculiar behavior is uncovered to be associated with the thermal excitation of a low-frequency phonon bath, and a theoretical model involving the excitation-wavelength-dependent populations of vibronic levels and the temperature-dependent nonradiative recombination processes is successfully constructed. Two main governing parameters, namely, the thermal activation energy Ea and the involved average phonon energy ΔE, are thus determined for the distinct thermal behaviors of Mn4+-ion luminescence. This demonstration may pave the way for manipulating the thermal behaviors of vibronic luminescence in solids to some extent.

15.
Life (Basel) ; 13(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36836808

RESUMO

Total knee arthroplasty (TKA) is widely used in clinical practice as an effective treatment for end-stage knee joint lesions. It can effectively correct joint deformities, relieve painful symptoms, and improve joint function. The reconstruction of lower extremity joint lines and soft tissue balance are important factors related to the durability of the implant; therefore, it is especially important to measure the joint lines and associated angles before TKA. In this article, we review the technological progress in the preoperative measurement of TKA.

16.
BMC Evol Biol ; 12: 165, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22938134

RESUMO

BACKGROUND: The basic helix-loop-helix (bHLH) transcription factors and their homologs form a superfamily that plays essential roles in transcriptional networks of multiple developmental processes. bHLH family members have been identified in over 20 organisms, including fruit fly, zebrafish, human and mouse. RESULT: In this study, we conducted a genome-wide survey for bHLH sequences, and identified 57 bHLH sequences encoded in complete genome sequence of the ponerine ant, Harpegnathos saltator. Phylogenetic analysis of the bHLH domain sequences classified these genes into 38 bHLH families with 23, 14, 10, 1, 8 and 1 members in group A, B, C, D, E and F, respectively. The number of PabHLHs (ponerine ant bHLHs) with introns is higher than many other insect species, and they are found to have introns with average lengths only inferior to those of pea aphid. In addition, two H. saltator bHLHs named PaCrp1 and PaSide locate on two separate contigs in the genome. CONCLUSIONS: A putative full set of PabHLH genes is comparable with other insect species and genes encoding Oligo, MyoRb and Figα were not found in genomes of all insect species of which bHLH family members have been identified. Moreover, in-family phylogenetic analyses indicate that the PabHLH genes are more closely related with Apis mellifera than others. The present study will serve as a solid foundation for further investigations into the structure and function of bHLH proteins in the regulation of H. saltator development.


Assuntos
Formigas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Genoma de Inseto/genética , Sequência de Aminoácidos , Animais , Formigas/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Drosophila melanogaster/genética , Estudo de Associação Genômica Ampla , Íntrons , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
17.
BMC Microbiol ; 12: 143, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817680

RESUMO

BACKGROUND: Avian pathogenic Escherichia coli (APEC) and uropathogenic E. coli (UPEC) are the two main subsets of extraintestinal pathogenic E. coli (ExPEC). Both types have multiple iron acquisition systems, including heme and siderophores. Although iron transport systems involved in the pathogenesis of APEC or UPEC have been documented individually in corresponding animal models, the contribution of these systems during simultaneous APEC and UPEC infection is not well described. To determine the contribution of each individual iron acquisition system to the virulence of APEC and UPEC, isogenic mutants affecting iron uptake in APEC E058 and UPEC U17 were constructed and compared in a chicken challenge model. RESULTS: Salmochelin-defective mutants E058ΔiroD and U17ΔiroD showed significantly decreased pathogenicity compared to the wild-type strains. Aerobactin defective mutants E058ΔiucD and U17ΔiucD demonstrated reduced colonization in several internal organs, whereas the heme defective mutants E058ΔchuT and U17ΔchuT colonized internal organs to the same extent as their wild-type strains. The triple mutant ΔchuTΔiroDΔiucD in both E058 and U17 showed decreased pathogenicity compared to each of the single mutants. The histopathological lesions in visceral organs of birds challenged with the wild-type strains were more severe than those from birds challenged with ΔiroD, ΔiucD or the triple mutants. Conversely, chickens inoculated with the ΔchuT mutants had lesions comparable to those in chickens inoculated with the wild-type strains. However, no significant differences were observed between the mutants and the wild-type strains in resistance to serum, cellular invasion and intracellular survival in HD-11, and growth in iron-rich or iron-restricted medium. CONCLUSIONS: Results indicated that APEC and UPEC utilize similar iron acquisition mechanisms in chickens. Both salmochelin and aerobactin systems appeared to be important in APEC and UPEC virulence, while salmochelin contributed more to the virulence. Heme bounded by ChuT in the periplasm appeared to be redundant in this model, indicating that other periplasmic binding proteins likely contributed to the observed no phenotype for the heme uptake mutant. No differences were observed between the mutants and their wild-type parents in other phenotypic traits, suggesting that other virulence mechanisms compensate for the effect of the mutations.


Assuntos
Enterobactina/análogos & derivados , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Escherichia coli/patogenicidade , Glucosídeos/metabolismo , Ácidos Hidroxâmicos/metabolismo , Ferro/metabolismo , Fatores de Virulência/metabolismo , Estruturas Animais/patologia , Animais , Galinhas , Modelos Animais de Doenças , Enterobactina/metabolismo , Escherichia coli/genética , Deleção de Genes , Heme/metabolismo , Histocitoquímica , Microscopia , Fatores de Virulência/genética
18.
Orthop Surg ; 14(3): 577-586, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35147295

RESUMO

OBJECTIVE: To study the effectiveness of a new spinal protection device for preventing and treating osteoporotic vertebral compression fractures (OVCFs) by finite element analysis (FEA). METHODS: One healthy volunteer and one patient with 1-segment lumbar vertebral compression fractures were included in this experimental study. The DICOM files of two different lumbar spiral computed tomography (CT) scans were converted into STL files, and 3D finite element models of the lumbar spine were generated for normal and L1 vertebral fracture spines. A new type of spinal protection device was applied to reduce the stress on the anterior vertebral edge and direct the center of gravity posteriorly. The stress distribution characteristics of different finite element models of the lumbar spine were analyzed, revealing the characteristics of the stress distributed along the spine under the action of the new spinal protection device. RESULTS: Under normal conditions, the stress was mainly distributed in the middle and posterior columns of the spine. When the anterior border of the L1 vertebral body was fractured and collapsed, the stress distribution shifted toward the anterior column due to the center of gravity being directed forward. According to finite element analysis of the spine with the new protection device, the stress in the middle and posterior columns tended to increase, and that in the anterior column decreased. After the new type of spinal fixation device was applied, the stress at the L1 and L2 vertebral endplates decreased to a certain extent, especially that at the L1 vertebral body. The maximum stress on the L1 vertebral body decreased by 20% after the auxiliary device was applied. CONCLUSIONS: According to the FEA results, the new spinal protection device can effectively prevent and treat osteoporotic vertebral compression fractures (OVCFs), and can alter the stress distribution in the spine and reduce the stress in the anterior column of the vertebral body, especially in vertebral compression fractures.


Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Análise de Elementos Finitos , Fraturas por Compressão/cirurgia , Humanos , Vértebras Lombares/lesões , Vértebras Lombares/cirurgia , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/prevenção & controle , Fraturas da Coluna Vertebral/cirurgia
19.
World J Clin Cases ; 10(6): 1903-1908, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35317132

RESUMO

BACKGROUND: Surgical treatment of knee osteoarthritis (KOA) complicated by extra-articular deformity has always been controversial regardless of whether it is simultaneous or staged. Simultaneous total knee arthroplasty (TKA) combined with supracondylar osteotomy without plate for treatment of KOA complicated by femoral varus deformity has not been reported in the literature. CASE SUMMARY: A 53-year-old Chinese woman complained of left knee pain for 6 years that worsened for 4 mo during her visit on April 3, 2020, accompanied by instability in walking, which seriously affected quality of life. According to her medical history and preoperative imaging, the patient was diagnosed with left KOA with varus deformity. We used the angular center of rotation principle for osteotomy of the femur deformity and placed a poststabilized femur prosthesis into the knee joint. At the same time, a 13 mm × 130 mm femur extension rod was used instead of a steel plate to fix the end of the femur osteotomy, reducing the possible complications caused by steel plate implantation and reducing the economic burden on patients. The operation successfully solved two major problems of KOA and varus deformity, and the clinical and imaging evaluation of postoperative follow-up were satisfactory. CONCLUSION: TKA and supracondylar femoral osteotomy can be used for simultaneous KOA treatment and deformity correction.

20.
Nanotechnology ; 22(22): 225201, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21454941

RESUMO

We investigate the thermoelectric effects of an Aharonov-Bohm (AB) interferometer with a quantum dot (QD) embedded in each of its arms, where the intra-dot Coulomb interaction between electrons in each QD is taken into account. Using Green's function methods and the equation of motion (EOM) technique, we find that the Seebeck coefficient and Lorenz number can be strongly enhanced when the chemical potential sweeps the molecular states associated with the Fano line-shapes in the transmission spectra, due to quantum interference effects between the bonding and antibonding molecular states. It is found that enhancement of the thermoelectric effects occurs between the two groups of conductance peaks in the presence of strong intra-dot Coulomb interaction-the reason being that a transmission node is developed in the Coulomb blockade regime. In this case, the maximum value of the Lorenz number approaches 10π(2)k(B)(2)/(3e(2)). Its thermoelectric conversion efficiency in the absence of phonon thermal conductance, described by the figure of merit ZT, approaches 2 at room temperature. Therefore, it may be used as a high-efficiency solid-state thermoelectric conversion device under certain circumstances.

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