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1.
Mol Cell ; 83(18): 3360-3376.e11, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37699397

RESUMO

Aging is associated with progressive phenotypic changes. Virtually all cellular phenotypes are produced by proteins, and their structural alterations can lead to age-related diseases. However, we still lack comprehensive knowledge of proteins undergoing structural-functional changes during cellular aging and their contributions to age-related phenotypes. Here, we conducted proteome-wide analysis of early age-related protein structural changes in budding yeast using limited proteolysis-mass spectrometry (LiP-MS). The results, compiled in online ProtAge catalog, unraveled age-related functional changes in regulators of translation, protein folding, and amino acid metabolism. Mechanistically, we found that folded glutamate synthase Glt1 polymerizes into supramolecular self-assemblies during aging, causing breakdown of cellular amino acid homeostasis. Inhibiting Glt1 polymerization by mutating the polymerization interface restored amino acid levels in aged cells, attenuated mitochondrial dysfunction, and led to lifespan extension. Altogether, this comprehensive map of protein structural changes enables identifying mechanisms of age-related phenotypes and offers opportunities for their reversal.


Assuntos
Senescência Celular , Longevidade , Longevidade/genética , Polimerização , Aminoácidos
2.
Nature ; 617(7962): 747-754, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37165189

RESUMO

While early multicellular lineages necessarily started out as relatively simple groups of cells, little is known about how they became Darwinian entities capable of sustained multicellular evolution1-3. Here we investigate this with a multicellularity long-term evolution experiment, selecting for larger group size in the snowflake yeast (Saccharomyces cerevisiae) model system. Given the historical importance of oxygen limitation4, our ongoing experiment consists of three metabolic treatments5-anaerobic, obligately aerobic and mixotrophic yeast. After 600 rounds of selection, snowflake yeast in the anaerobic treatment group evolved to be macroscopic, becoming around 2 × 104 times larger (approximately mm scale) and about 104-fold more biophysically tough, while retaining a clonal multicellular life cycle. This occurred through biophysical adaptation-evolution of increasingly elongate cells that initially reduced the strain of cellular packing and then facilitated branch entanglements that enabled groups of cells to stay together even after many cellular bonds fracture. By contrast, snowflake yeast competing for low oxygen5 remained microscopic, evolving to be only around sixfold larger, underscoring the critical role of oxygen levels in the evolution of multicellular size. Together, this research provides unique insights into an ongoing evolutionary transition in individuality, showing how simple groups of cells overcome fundamental biophysical limitations through gradual, yet sustained, multicellular evolution.


Assuntos
Aclimatação , Evolução Biológica , Agregação Celular , Saccharomyces cerevisiae , Modelos Biológicos , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Anaerobiose , Aerobiose , Oxigênio/análise , Oxigênio/metabolismo , Forma Celular , Agregação Celular/fisiologia
3.
Small ; 20(12): e2307500, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37940631

RESUMO

The promising cyclometalated iridium (III) complexes have been proved to possess great potential in vacuum-deposited organic light-emitting diodes (OLEDs) applications for full-color displays and white solid-state lighting sources. Herein, based on the unique bidentate ligand of dibenzo[a,c]phenazine (dbpz) group with strong conjugated effect of aromatic rings for red emission, four novel [3+2+1] coordinated iridium (III) emissive materials have been rationally designed and synthesized. The monodentate ligands of -CN and -OCN have been effectively employed to tune the deep-red emission of 628-675 nm with high photoluminescence quantum yields up to 98%. Moreover, all devices displayed deep-red color coordinates ranging from (0.675, 0.325) to (0.716, 0.284), which is close to the standard-red color coordinates of (0.708, 0.292), as recommended by International Telecommunication Union Radiocommunication (ITU-R) BT.2020. The device based on nBuIr(dbpz)CN with an exciplex cohost has exhibited maximum external quantum efficiencies of 20.7% and good stability. With nBuIr(dbpz)CN as an effective sensitizer, the nBuIr(dbpz)OCN based phosphorescent OLED devices have successfully demonstrated cascading energy transfer processes, contributing to pure red emission with maximum luminance as high as 6471 cd m-2. Therefore, this work has been successfully demonstrated rational molecular design strategy of [3+2+1] iridium complexes to obtain highly efficient deep-red electrophosphorescent emission.

4.
Small ; 20(24): e2311114, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38157494

RESUMO

Due to the relatively low photoluminescence quantum yield (PLQY) and horizontal dipole orientation of doped films, anthracene-based fluorescent organic light-emitting diodes (F-OLEDs) have faced a great challenge to achieve high external quantum efficiency (EQE). Herein, a novel approach is introduced by incorporating penta-helicene into anthracene, presented as linear-shaped 3-(4-(10-phenylanthracen-9-yl)phenyl)dibenzo[c,g]phenanthrene (BABH) and 3-(4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)dibenzo[c,g]phenanthrene (NABH). These blue hosts exhibit minimal intermolecular overlap of π-π stacking, effectively suppressing excimer formation, which facilitates the effective transfer of singlet energy to the fluorescent dopant for PLQY as high as 90%. Additionally, the as-obtained two hosts of BABH and NABH have effectively demonstrated major horizontal components transition dipole moments (TDM) and high thermal stability with glass transitional temperature (Tg) surpassing 188 °C, enhancing the horizontal dipole orientation of their doped films to be 89% and 93%, respectively. The OLEDs based on BABH and NABH exhibit excellent EQE of 10.5% and 12.4% at 462 nm and device lifetime up to 90% of the initial luminance over 4500 h at 100 cd m-2, which has firmly established them as among the most efficient blue F-OLEDs based on anthracene to date to the best knowledge. This work provides an instructive strategy to design an effective host for highly efficient and stable F-OLEDs.

5.
Langmuir ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39024040

RESUMO

Given the limitations of micromechanical experiments and molecular dynamics simulations, the normal compression process of clay aggregates was simulated under different vertical pressures (P), numbers of particles, loading methods, and environments by a Gay-Berne potential model. On the basis of the variations of particle orientation and the distribution of stacks, the evolution of deformation and stresses was elucidated. The results showed that the effects of the pressure level and loading environment on the deformation were significant. In the range of 0.1-10 MPa, the changes in the void ratio were essentially the evolution of the distribution of stacks determined by attractive short-range van der Waals interactions. The deformation under constant pressure was larger than that under step loading. Because the interactions between clay particles were mainly controlled by mechanical force when in the range of 40-100 MPa, the void ratios under various loading conditions were consistent. It was also found that changes in three-dimensional stresses during compression were dependent on those of the distribution of stacks. In the vacuum environment, owing to the lateral movement of interlocked small stacks, the horizontal stress decreased. The lateral pressure coefficients (k) were greater in an atmospheric environment because the anisotropic particle orientation was relatively less obvious. In the range of 10-100 MPa, when the loading path became longer, k was similar in vacuum but became smaller in an atmosphere. If the initial loading pressure was increased, the number of large stacks sharply increased and the anisotropy was significant in a vacuum environment, which was less prone to lateral expansion. In contrast, more consistent particle arrangements were maintained in an atmosphere. This work will be conducive to explaining experimental observations of long-term ripening.

6.
Clin Orthop Relat Res ; 481(1): 177-189, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36135966

RESUMO

BACKGROUND: Low-dose antibiotic-loaded acrylic cement is routinely used for preventing skeletal infection or reimplantation in patients with periprosthetic joint infections. However, few reports about the selection of antibiotics in acrylic cement for antigram-negative bacteria have been proposed. QUESTIONS/PURPOSES: (1) Does the addition of antibiotics (tobramycin, meropenem, piperacillin, ceftazidime, ciprofloxacin, and aztreonam) to acrylic cement adversely affect compressive strength before and after elution? (2) Which antibiotics have the highest cumulative release within 28 days? (3) Which antibiotics showed antimicrobial activity within 28 days? (4) Does meropenem-loaded cement improve body weight, temperature, and other inflammatory markers compared with control unloaded cement? METHODS: This is an in vitro study that assessed the mechanical strength, antibiotic elution, and antibacterial properties of antibiotic-loaded cement, combined with an animal study in a rat model that evaluated key endpoints from the animal study. In the in vitro study, we added 2 g of tobramycin (TOB), meropenem (MEM), piperacillin (PIP), ceftazidime (CAZ), ciprofloxacin (CIP), and aztreonam (ATM) to 40 g of acrylic cement. The compressive strength, elution, and in vitro antibacterial properties of the antibiotic-loaded cement were detected. Thirty male rats were randomly divided into two groups: CON (antibiotic-unloaded cement) and MEM (meropenem-loaded cement, which had the most stable antibacterial properties of the six tested antibiotic-loaded cements in vitro within 28 days). The right tibia of all rats underwent arthroplasty and was implanted with the cement, followed by inoculation with Pseudomonas aeruginosa in the knee. General status, serum biomarkers, radiology, microbiological assay, and histopathological tests were assessed over 14 days postoperatively. RESULTS: The compressive strength of all tested antibiotic cement combinations exceeded the 70 MPa threshold (the requirement established in ISO 5833). The cumulative release proportions of the raw antibiotic in cement were 1182.8 ± 37.9 µg (TOB), 355.6 ± 16.2 µg (MEM), 721.2 ± 40.3 µg (PIP), 477.4 ± 37.1 µg (CAZ), 146.5 ± 11.3 µg (CIP), and 372.1 ± 14.5 µg (ATM) within 28 days. Over a 28-day period, meropenem cement demonstrated antimicrobial activities against the four tested gram-negative bacteria ( Escherichia coli , P. aeruginosa , Klebsiella pneumoniae , and Proteus vulgaris ). Ciprofloxacin cement inhibited E. coli growth, ceftazidime and aztreonam cement inhibited K. pneumonia growth, and tobramycin cement inhibited P. aeruginosa . Only meropenem demonstrated antimicrobial activity against all gram-negative bacteria on agar diffusion bioassay. Rats treated with meropenem cement showed improved body weight (control: 280.1 ± 4.2 g, MEM: 288.5 ± 6.6 g, mean difference 8.4 [95% CI 4.3 to 12.6]; p < 0.001), improved knee width (control: 13.5 ± 0.3 mm, MEM: 11.8± 0.4 mm, mean difference 1.7 [95% CI 1.4 to 2.0]; p < 0.001), decreased inflammatory marker (control: 316.7 ± 45.0 mm, MEM: 116.5 ± 21.8 mm, mean difference 200.2 [95% CI 162.3 to 238.2]; p < 0.001), decreased radiographic scores (control: 17.7 ± 2.0 mm, MEM: 10.7± 1.3 mm, mean difference 7.0 [95% CI 5.4 to 8.6]; p < 0.001), improved bone volume/total volume (control: 8.7 ± 3.0 mm, MEM: 28.5 ± 5 .5 mm, mean difference 19.8 [95% CI 13.3 to 26.2]; p < 0.001), decreased Rissing scale scores of the knee gross pathology (control: 3.3 ± 0.5, MEM: 1.1 ± 0.7, mean difference 2.2 [95% CI 1.7 to 2.7]; p < 0.001), decreased Petty scale scores of knee synovium (control: 2.9 ± 0.4 mm, MEM: 0.7 ± 0.7 mm, mean difference 2.1 [95% CI 1.7 to 2.5]; p < 0.001), and decreased bacterial counts of the bone and soft tissues and negative bacterial cultures of cement (p < 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). CONCLUSION: In this current study, MEM cement had the most stable in vitro antimicrobial activities, effective in vivo activity while having acceptable mechanical and elution characteristics, and it may be an effective prophylaxis against skeletal infection caused by gram-negative bacteria. CLINICAL RELEVANCE: Meropenem-loaded acrylic cement is a potentially effective prevention measure for skeletal infection caused by gram-negative bacteria; however, more related clinical research is needed to further evaluate the safety and efficacy.


Assuntos
Ceftazidima , Osteomielite , Masculino , Animais , Ratos , Meropeném/farmacologia , Ceftazidima/farmacologia , Aztreonam/farmacologia , Escherichia coli , Antibacterianos/farmacologia , Cimentos Ósseos , Tobramicina , Piperacilina , Ciprofloxacina , Modelos Animais , Testes de Sensibilidade Microbiana
7.
Antimicrob Agents Chemother ; 66(2): e0164121, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34807762

RESUMO

Although intra-articular vancomycin powder (VP) is sometimes applied before the closure of the incision to prevent periprosthetic joint infection (PJI) after joint replacement, the dosage, efficacy, and safety remain controversial. This study aimed to explore the dosage, efficacy, and safety of intra-articular VP in the prophylaxis of infection after total knee arthroplasty (TKA) in a rat model. Sixty male rats were randomly divided into five groups after receiving TKA: control (no antibiotics); systemic vancomycin (SV) (intraperitoneal injection, 88 mg/kg of body weight, equal to 1 g in a patient weighing 70 kg); and VP0.5, VP1.0, and VP2.0 (44 mg/kg, 88 mg/kg and 176 mg/kg, respectively; intra-articular). All animals were inoculated in the knee with methicillin-resistant S. aureus (MRSA). General status, serum biomarkers, radiology, microbiological assay, and histopathological tests were assessed within 14 days postoperation. Compared with the control and SV groups, bacterial counts, knee width, tissue inflammation, and osteolysis were reduced in the VP0.5, VP1.0, and VP2.0 groups, without notable body weight loss and incision complications. Among all the VP groups, VP1.0 and VP2.0 groups presented superior outcomes with regard to knee width and tissue inflammation than the VP0.5 group. Microbial culture indicated that no MRSA survived in the knee of VP1.0 and VP2.0 groups, while bacteria growth was observed in the VP0.5 group. No obvious changes in the structure and functional biomarkers of liver and kidney were observed in either the SV or VP groups. Therefore, intra-articular vancomycin powder at a dosage from 88 mg/kg to 176 mg/kg may be effective and safe in preventing PJI induced by methicillin-resistant S. aureus in the rat TKA model.


Assuntos
Artrite Infecciosa , Artroplastia do Joelho , Staphylococcus aureus Resistente à Meticilina , Infecções Relacionadas à Prótese , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Artrite Infecciosa/tratamento farmacológico , Artroplastia do Joelho/efeitos adversos , Masculino , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/prevenção & controle , Ratos , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/farmacologia
8.
Antimicrob Agents Chemother ; 66(6): e0011222, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35499314

RESUMO

Deep knee infection (DKI) after anterior cruciate ligament reconstruction (ACLR) is rare and challenging. The optimal treatment strategy for infection after ACLR remains controversial. This study aimed to investigate the optimal treatment for early infection after ACLR surgery. Rats with unilateral ACLR were injected with 3.0 × 105 colony forming units (CFU) of Staphylococcus aureus in the knee joint for 7 days. Next, with surgical debridement (SD) and/or 21 days of antimicrobial (systemic vancomycin and oral rifampicin [SVR]) therapy, rats were euthanatized and samples harvested. We evaluated signs of infection by general postoperative conditions, serum inflammatory markers, microbiological counting, knee radiographs, micro-computed tomography (micro-CT), histologic staining, and scanning electron microscopy (SEM). Clinically, the data from 12 patients who suffered from DKI after ACLR were analyzed retrospectively. The DKI rats treated with SVR showed better outcomes in general postoperative conditions, serum inflammatory markers, microbiological counting, biofilm on the interference screw and graft, radiographic signs of periarticular osseous destruction, and inflammatory reaction in the joint tissues than those with SD treatment, while the DKI rats with SD and SVR administration showed the best outcomes. Rats which received SD and SVR administration had their S. aureus contamination completely eradicated. All patients treated with SD & SVR or SVR alone had effectively controlled knee infections and achieved good knee function outcomes in the 6 months after treatment, but one patient developed more serious knee infections. Therefore, surgical debridement combined with systemic antibiotics treatment could effectively eliminate S. aureus contamination in the DKI rat model and in patients after ACLR without affecting knee function. Treatment with systemic antibiotics could also control early DKI, which would be especially applicable in patients who could not tolerate surgery.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Infecções Estafilocócicas , Animais , Lesões do Ligamento Cruzado Anterior/tratamento farmacológico , Lesões do Ligamento Cruzado Anterior/etiologia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/métodos , Antibacterianos/uso terapêutico , Desbridamento , Humanos , Articulação do Joelho/cirurgia , Ratos , Estudos Retrospectivos , Staphylococcus aureus , Infecção da Ferida Cirúrgica , Resultado do Tratamento , Vancomicina/uso terapêutico , Microtomografia por Raio-X
9.
Appl Opt ; 61(31): 9135-9142, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607046

RESUMO

We propose a method of combining a double optical path detection system with a phase generation carrier arctangent algorithm. The feasibility of eliminating the influence of modulation depth by the double optical path detection vibration measurement system is verified by simulation and experiment. Results show that the average total harmonic distortion of the single frequency signal is 1%, and the signal-to-noise ratio of the speech signal is improved by an average of 5.6 dB. Therefore, the double optical path detection system can eliminate the influence of modulation depth, avoid nonlinear distortion, and improve the detection performance of the system.

10.
Antimicrob Agents Chemother ; 65(9): e0030321, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34181479

RESUMO

The rate of eradication of periprosthetic joint infection (PJI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is still not satisfactory with systemic vancomycin administration after one-stage revision arthroplasty. This study aimed to explore the effectiveness and safety of intraarticular (IA) injection of vancomycin in the control of MRSA PJI after one-stage revision surgery in a rat model. Two weeks of intraperitoneal (IP) and/or IA injection of vancomycin was used to control the infection after one-stage revision surgery. The MRSA PJI rats treated with IA injection of vancomycin showed better outcomes in skin temperature, bacterial counts, biofilm on the prosthesis, serum α1-acid glycoprotein levels, residual bone volume, and inflammatory reaction in the joint tissue, compared with those treated with IP vancomycin, while the rats treated with IP and IA administration showed the best outcomes. However, only the IP and IA administration of vancomycin could eradicate MRSA. Minimal changes in renal pathology were observed in the IP and IP plus IA groups but not in the IA group, while no obvious changes were observed in the liver or in levels of serum markers, including creatinine, alanine aminotransferase, and aspartate aminotransferase. Therefore, IA use of vancomycin is effective and safe in the MRSA PJI rat model and is better than systemic administration, while IA and systemic vancomycin treatment could eradicate the infection with a 2-week treatment course.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Relacionadas à Prótese , Infecções Estafilocócicas , Animais , Antibacterianos/uso terapêutico , Próteses e Implantes , Infecções Relacionadas à Prótese/tratamento farmacológico , Ratos , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico
11.
Curr Genet ; 67(6): 871-876, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34114051

RESUMO

Multicellularity has evolved numerous times across the tree of life. One of the most fundamental distinctions among multicellular organisms is their developmental mode: whether they stay together during growth and develop clonally, or form a group through the aggregation of free-living cells. The five eukaryotic lineages to independently evolve complex multicellularity (animals, plants, red algae, brown algae, and fungi) all develop clonally. This fact has largely been explained through social evolutionary theory's lens of cooperation and conflict, where cheating within non-clonal groups has the potential to undermine multicellular adaptation. Multicellular organisms that form groups via aggregation could mitigate the costs of cheating by evolving kin recognition systems that prevent the formation of chimeric groups. However, recent work suggests that selection for the ability to aggregate quickly may constrain the evolution of highly specific kin recognition, sowing the seeds for persistent evolutionary conflict. Importantly, other features of aggregative multicellular life cycles may independently act to constrain the evolution of complex multicellularity. All known aggregative multicellular organisms are facultatively multicellular (as opposed to obligately multicellular), allowing unicellular-level adaptation to environmental selection. Because they primarily exist in a unicellular state, it may be difficult for aggregative multicellular organisms to evolve multicellular traits that carry pleiotropic cell-level fitness costs. Thus, even in the absence of social conflict, aggregative multicellular organisms may have limited potential for the evolution of complex multicellularity.


Assuntos
Evolução Biológica , Eucariotos/fisiologia , Evolução Clonal , Eucariotos/citologia
12.
BMC Microbiol ; 21(1): 333, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876010

RESUMO

BACKGROUND: Intra-wound vancomycin powder (VP) has been used in clinical practice to prevent periprosthetic joint infection (PJI) after primary knee/hip arthroplasty. The role of intra-wound VP in the setting of debridement and implant exchange after PJI remains undefined. This study aimed to explore the efficacy and safety of intra-wound VP in the control of methicillin-resistant S. aureus (MRSA) infection after debridement and implant exchange. METHODS: PJI modeling by knee prosthesis implantation and MRSA inoculation, debridement and implant exchange were performed in Wistar rats successively to mimic the one-stage exchange arthroplasty of PJI patients. Two weeks of systemic vancomycin (SV) or/and intraoperative intra-wound VP of single dosage were applied after revision surgery. RESULTS: No post-surgery deaths, incision complications and signs of drug toxicity were observed. The microbial counts of SV or intra-wound VP group were significantly reduced compared with the control group, while bacteria were still detected on the bone, soft-tissue and prosthesis. The elimination of bacterial counts, along with improvement of tissue inflammation and serum inflammatory markers, were observed in the rats with SV plus intra-wound VP. Serum levels of vancomycin in all groups were lower than that of causing nephrotoxicity, while no statistic difference was observed in the serum biochemical marker among the groups. CONCLUSIONS: Intra-wound VP is effective after debridement and implant exchange in our current rat PJI model. Neither SV nor intra-wound VP alone could eradicate the bacteria within a two-weeks treatment course, while SV plus intra-wound VP could eliminate the MRSA infection, without notable hepatic or renal toxicity and any incision complications.


Assuntos
Artroplastia do Joelho , Desbridamento , Infecções Relacionadas à Prótese/prevenção & controle , Vancomicina/administração & dosagem , Animais , Antibacterianos/administração & dosagem , Artroplastia do Joelho/efeitos adversos , Desbridamento/efeitos adversos , Modelos Animais de Doenças , Prótese do Joelho/efeitos adversos , Prótese do Joelho/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pós , Infecções Relacionadas à Prótese/etiologia , Ratos , Ratos Wistar , Infecções Estafilocócicas/etiologia , Infecções Estafilocócicas/prevenção & controle , Resultado do Tratamento , Vancomicina/farmacologia
13.
Appl Opt ; 60(27): 8258-8266, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34612922

RESUMO

An acoustic graphene plasmon (AGP) resonator based on gold nanowire arrays structure is proposed in this paper. The resonator is designed by continuous graphene layer/gold nanowire arrays/optical resonant cavity. The infrared light excites the AGP in the graphene/gold arrays structure and propagates along the graphene surface. The coupling efficiency can be improved by the optical resonator cavity. The finite-difference time-domain method is used to simulate and optimize the property of the resonator. The results show that the resonator has a stronger optical limiting effect and higher coupling efficiency. The AGPs are a prospective platform that enhances light-matter interactions, reduces spread loss, and exhibits a double resonance absorption phenomenon in the studied mid-infrared wavelength range. The research results provide a basis for the design of optoelectronic devices and more.

14.
BMC Musculoskelet Disord ; 22(1): 787, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517870

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a potentially fatal complication after arthroplasty. Numerous prophylactic strategies and studies to reduce VTEs have focused on the duration of the hospital stay and on few extramural hospitals. This study aimed to investigate extramural hospital management of VTE after total hip/knee arthroplasty (THA/TKA) in China with a novel survey tool. METHODS: A total of 180 patients undergoing arthroplasty, including 68 THA patients and 112 TKA patients, were enrolled in this study. All patients received anticoagulant treatment management. A survey querying VTE management and adherence, such as therapy information, understanding of anticoagulation, satisfaction with the ability of medical staff, and satisfaction with health care costs, was administered by a questionnaire (TKA/THA Patients' Experience with Anticoagulation in the Post-discharge Period) for quality improvement. RESULTS: The average age of the patients was 65.27 ± 13.62 years. All patients knew their follow-up times. 85 % of them were suggested that re-examine at the next 14 days, and the others at the next 28 days. All patients continued to visit the orthopaedic clinic after discharge without choosing other types of outpatient services, such as an anticoagulant clinic or home visit with a nurse/pharmacist or remote evaluation by telephone. A total of 96.6 % of all patients used new oral anticoagulants, and the most common treatment duration was 2-4 weeks (93.3 %). 48 % informed their physicians that they were taking anticoagulation medications when they visited ophthalmology, dentistry, dermatology, and other departments. The overall rate of satisfaction with anticoagulation management was 81.67 %, and 6.67 % of patients were not unsatisfied with their medical expenses. Patient compliance decreased with increasing follow-up time. Continuous follow-ups after discharge significantly improved patient compliance. CONCLUSIONS: These results elucidate how we can improve the quality of anticoagulation. Continuous follow-up appointments for 30 days after discharge, especially for individuals over 65 years old, significantly improved patient satisfaction and reduced the incidence of VTE and medical costs.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Tromboembolia Venosa , Assistência ao Convalescente , Idoso , Anticoagulantes/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , China/epidemiologia , Hospitais , Humanos , Pessoa de Meia-Idade , Alta do Paciente , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Inquéritos e Questionários , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/epidemiologia
15.
J Stroke Cerebrovasc Dis ; 30(7): 105812, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33895427

RESUMO

OBJECTIVES: Soft robotic hands are proposed for stroke rehabilitation in terms of their high compliance and low inherent stiffness. We investigated the clinical efficacy of a soft robotic hand that could actively flex and extend the fingers in chronic stroke subjects with different levels of spasticity. METHODS: Sixteen chronic stroke subjects were recruited into this single-group study. Subjects underwent 20 sessions of 1-hour EMG-driven soft robotic hand training. Training effect was evaluated by the pre-training and post-training assessments with the clinical scores: Action Research Arm Test(ARAT), Fugl-Meyer Assessment for Upper Extremity(FMA-UE), Box-and-Block test(BBT), Modified Ashworth Scale(MAS), and maximum voluntary grip strength. RESULTS: For all the recruited subjects (n = 16), significant improvement of upper limb function was generally observed in ARAT (increased mean=2.44, P = 0.032), FMA-UE (increased mean=3.31, P = 0.003), BBT (increased mean=1.81, P = 0.024), and maximum voluntary grip strength (increased mean=2.14 kg, P < 0.001). No significant change was observed in terms of spasticity with the MAS (decreased mean=0.11, P = 0.423). Further analysis showed subjects with mild or no finger flexor spasticity (MAS<2, n = 9) at pre-training had significant improvement of upper limb function after 20 sessions of training. However, for subjects with moderate and severe finger flexor spasticity (MAS=2,3, n = 7) at pre-training, no significant change in clinical scores was shown and only maximum voluntary grip strength had significant increase. CONCLUSION: EMG-driven rehabilitation training using the soft robotic hand with flexion and extension could be effective for the functional recovery of upper limb in chronic stroke subjects with mild or no spasticity.


Assuntos
Exoesqueleto Energizado , Mãos/inervação , Robótica/instrumentação , Reabilitação do Acidente Vascular Cerebral/instrumentação , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Fenômenos Biomecânicos , Avaliação da Deficiência , Eletromiografia , Desenho de Equipamento , Feminino , Estado Funcional , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
16.
Int J Mol Sci ; 23(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35008895

RESUMO

Hyperosmolality and various other stimuli can trigger an increase in cytoplasmic-free calcium concentration ([Ca2+]cyt). Members of the Arabidopsis thaliana (L.) reduced hyperosmolality-gated calcium-permeable channels (OSCA) gene family are reported to be involved in sensing extracellular changes to trigger hyperosmolality-induced [Ca2+]cyt increases and controlling stomatal closure during immune signaling. Wheat (Triticum aestivum L.) is a very important food crop, but there are few studies of its OSCA gene family members. In this study, 42 OSCA members were identified in the wheat genome, and phylogenetic analysis can divide them into four clades. The members of each clade have similar gene structures, conserved motifs, and domains. TaOSCA genes were predicted to be regulated by cis-acting elements such as STRE, MBS, DRE1, ABRE, etc. Quantitative PCR results showed that they have different expression patterns in different tissues. The expression profiles of 15 selected TaOSCAs were examined after PEG (polyethylene glycol), NaCl, and ABA (abscisic acid) treatment. All 15 TaOSCA members responded to PEG treatment, while TaOSCA12/-39 responded simultaneously to PEG and ABA. This study informs research into the biological function and evolution of TaOSCA and lays the foundation for the breeding and genetic improvement of wheat.


Assuntos
Canais de Cálcio , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Estresse Fisiológico/genética , Triticum , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Família Multigênica , Proteínas de Plantas/genética , Triticum/genética , Triticum/metabolismo
17.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207287

RESUMO

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.


Assuntos
Ácido Abscísico/metabolismo , Agaricales/patogenicidade , Proteínas Fúngicas/genética , Gastrodia/microbiologia , Lignina/metabolismo , Proteínas de Plantas/genética , Agaricales/genética , Agaricales/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas Fúngicas/metabolismo , Gastrodia/genética , Gastrodia/crescimento & desenvolvimento , Gastrodia/metabolismo , Germinação , Lacase/genética , Lacase/metabolismo , Lignina/genética , Peroxidases/genética , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Simbiose , Transcriptoma
18.
Haemophilia ; 26(5): 873-881, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32700372

RESUMO

AIMS: Haemophilic pseudotumor (HPT) is a rare but challenging complication of haemophilia. This study was intended to provide our experience about clinical characteristics and surgical treatment of HPT. METHODS: Clinical medical records were retrieved from the Hemophilia Center, Nanfang Hospital, to identify the patients who had been surgically treated from 1 January 2006 to 31 December 2017 with a definite diagnosis of HPT. Their clinical features, surgical management, outcomes and complications after surgery were analysed. RESULTS: We identified 34 patients with HPT who had surgical treatment over a 12-year period and five of them had multiple HPTs. The incidence of HPT at this centre was 2.3% over the dozen years. A previous trauma leading to the development of HPT was reported in 18 cases (52.9%). The HPT affected only soft tissue in 7 patients, bone and soft tissue in 25 ones and joint in 2 ones. Preoperative infection and fistula formation happened in ten patients, two of whom were related to abdominal HPTs. Enterococcus faecalis was cultured in five cases with fistula formation. HPT associated with pathological fracture was observed in five cases, two of whom were treated by external fixation and 3 by HPT resection and metallic internal fixation. Amputation was performed for nine patients, 6 of whom had preoperative infection and fistula formation. Their follow-up duration averaged 4.2 ± 2.9 years (range, from 1 to 13.5 years) after surgery. Of all our cases, three suffered from postoperative infection, five from recurrence of HPT and two with external fixation from fracture non-union. CONCLUSIONS: HPT patients with preoperative infection had worse prognosis than those without. Surgical treatment plus intensive replacement therapy was effective for HPT but with a high rate of complications. HPT resection and metallic internal fixation rather than external fixation should be recommended for HPT patients with pathological fracture.


Assuntos
Hemofilia A/complicações , Pseudotumor Cerebral/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pseudotumor Cerebral/patologia , Estudos Retrospectivos , Resultado do Tratamento
19.
J Hand Surg Am ; 45(10): 938-946, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32473835

RESUMO

PURPOSE: This study was intended to characterize the epidemiological features of thumb polydactyly (TP) in South China. METHODS: Clinical records were retrieved from 1 central hospital in South China to identify the patients with a definite diagnosis of TP from January 2004 to January 2017. The cases were classified by their x-ray appearance. The data collected included sex, age at first operation, reoperation, family history, unilateral/bilateral polydactyly, right/left hand involvement in unilateral cases, classification of polydactyly, and the presence of associated congenital anomalies. RESULTS: A total of 428 patients with a definite diagnosis of TP were identified (278 males and 150 females) involving 483 cases, 373 unilateral and 55 bilateral. A syndrome or associated congenital anomaly was found in 26 (18 unilateral and 8 bilateral cases). A dominant thumb, larger and more developed, was observed in 448 hands (93%), and was the ulnar thumb in 433. Owing to postoperative complications, 31 thumbs (6.4%) underwent reoperation. The average interval from initial surgery to reoperation was 4.8 years. CONCLUSIONS: Thumb polydactyly had a male predominance in this Chinese cohort, mostly occurring on the right hand with an ulnar dominant thumb. Bilateral cases had a higher incidence of associated anomaly and positive family history than unilateral cases. The need for additional surgery for TP might occur as late as 4.8 years after primary surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Procedimentos de Cirurgia Plástica , Polidactilia , China/epidemiologia , Feminino , Humanos , Masculino , Polidactilia/diagnóstico por imagem , Polidactilia/epidemiologia , Polidactilia/cirurgia , Estudos Retrospectivos , Polegar/anormalidades , Polegar/diagnóstico por imagem , Polegar/cirurgia
20.
Appl Opt ; 58(7): 1824-1829, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874222

RESUMO

A surface plasmon resonance biosensor based on a graphene-decorated grating excitation structure is proposed in this paper. The biosensor consists of a three-layer structure, including a graphene layer, a grating layer, and a high refractive index layer. The material of the grating layer is silica. The graphene is physically deposited on the grating ridges. An incident light with transverse magnetic polarization is used to excite surface plasmons in the mid-infrared spectral region, which is highly localized at both ends of the graphene layer. The property of the sensor is improved by the high refractive index dielectric layer, which enhances the absorption of incident light and increases the depth of the spectra. The finite-difference time-domain method is used to simulate the property of the sensor. The structure of the sensor could be optimized by changing the structural parameters and comparing the simulation results. The effective refractive index (RI) on the surface and the wavelength of the reflective resonance absorption peak will be changed when the surface of graphene adsorbs the surrounding analyte. The results show that the relationship between the analyte RI and the resonance wavelength is linear. The measurement range of analyte RI is 1-1.8, and the sensitivity is 2780 nm/RIU.


Assuntos
Grafite/química , Fenômenos Ópticos , Ressonância de Plasmônio de Superfície/instrumentação , Simulação por Computador , Refratometria , Dióxido de Silício/química
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