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1.
Immune Netw ; 24(3): e19, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974213

RESUMO

The influenza virus poses a global health burden. Currently, an annual vaccine is used to reduce influenza virus-associated morbidity and mortality. Most influenza vaccines have been developed to elicit neutralizing Abs against influenza virus. These Abs primarily target immunodominant epitopes derived from hemagglutinin (HA) or neuraminidase (NA) of the influenza virus incorporated in vaccines. However, HA and NA are highly variable proteins that are prone to antigenic changes, which can reduce vaccine efficacy. Therefore, it is essential to develop universal vaccines that target immunodominant epitopes derived from conserved regions of the influenza virus, enabling cross-protection among different virus variants. The internal proteins of the influenza virus serve as ideal targets for universal vaccines. These internal proteins are presented by MHC class I molecules on Ag-presenting cells, such as dendritic cells, and recognized by CD8 T cells, which elicit CD8 T cell responses, reducing the likelihood of disease and influenza viral spread by inducing virus-infected cell apoptosis. In this review, we highlight the importance of CD8 T cell-mediated immunity against influenza viruses and that of viral epitopes for developing CD8 T cell-based influenza vaccines.

2.
Adv Sci (Weinh) ; 11(14): e2306497, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311584

RESUMO

Cell migration interacting with continuously changing microenvironment, is one of the most essential cellular functions, participating in embryonic development, wound repair, immune response, and cancer metastasis. The migration process is finely tuned by integrin-mediated binding to ligand molecules. Although numerous biochemical pathways orchestrating cell adhesion and motility are identified, how subcellular forces between the cell and extracellular matrix regulate intracellular signaling for cell migration remains unclear. Here, it is showed that a molecular binding force across integrin subunits determines directional migration by regulating tension-dependent focal contact formation and focal adhesion kinase phosphorylation. Molecular binding strength between integrin αvß3 and fibronectin is precisely manipulated by developing molecular tension probes that control the mechanical tolerance applied to cell-substrate interfaces. This data reveals that integrin-mediated molecular binding force reduction suppresses cell spreading and focal adhesion formation, attenuating the focal adhesion kinase (FAK) phosphorylation that regulates the persistence of cell migration. These results further demonstrate that manipulating subcellular binding forces at the molecular level can recapitulate differential cell migration in response to changes of substrate rigidity that determines the physical condition of extracellular microenvironment. Novel insights is provided into the subcellular mechanics behind global mechanical adaptation of the cell to surrounding tissue environments featuring distinct biophysical signatures.


Assuntos
Integrinas , Ligantes , Proteína-Tirosina Quinases de Adesão Focal , Adesão Celular/fisiologia , Movimento Celular
3.
Ann Surg Treat Res ; 105(5): 281-289, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023436

RESUMO

Purpose: Globally, chronic kidney disease (CKD) is common and has been associated with an increased risk of colorectal cancer (CRC). There is a dearth of literature on the real-world morbidity and mortality associated with CKD comorbid with CRC. This study was performed to evaluate real-world survival outcomes of colorectal malignancy in Korean CKD patients. Methods: The National Health Insurance Service of Korea provided data on patients who underwent surgical resection among patients diagnosed with CRC from 2002 to 2019. Results: A total of 219,550 patients were included: 6,181 patients with underlying CKD and 213,369 patients without it. Each morbidity was significantly higher in the CKD-CRC group, and the postoperative mortality rates for the 30-day (3.11% vs. 1.78%, P < 0.001), 60-day (5.95% vs. 3.83%, P < 0.001), and 90-day mortality rate (8.12% vs. 5.32%, P < 0.001) were significantly higher in the CKD group. The median survival time (MST, year) was significantly lower in the CKD-CRC group (5.63; interquartile range [IQR], 5.26-5.91) than in the non-CKD-CRC group (8.71; IQR, 8.37-8.93). MST was significantly lower among CKD patients who received chemotherapy after adjustment by multivariate analysis (adjusted hazard ratio [HR], 1.43; 95% confidence interval [CI], 1.37-1.49; P < 0.001]). Subgroup analysis showed that in the CKD-CRC group, MST was lower in patients who received dialysis than in those who did not, even after multivariate analysis (adjusted HR, 2.38; 95% CI, 2.20-2.58; P < 0.001). Conclusion: Prevention of CKD-to-end-stage renal disease progression should be adopted as a strategy to increase postoperative survival, along with active surveillance and cancer treatment.

4.
JCI Insight ; 8(18)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737261

RESUMO

Spinal muscular atrophy (SMA) is a pediatric-onset neuromuscular disorder caused by insufficient survival motor neuron (SMN) protein. SMN restorative therapies are now approved for the treatment of SMA; however, they are not curative, likely due to a combination of imperfect treatment timing, inadequate SMN augmentation, and failure to optimally target relevant organs. Here, we consider the implications of imperfect treatment administration, focusing specifically on outcomes for skeletal muscle. We examine the evidence that muscle plays a contributing role in driving neuromuscular dysfunction in SMA. Next, we discuss how SMN might regulate the health of myofibers and their progenitors. Finally, we speculate on therapeutic outcomes of failing to raise muscle SMN to healthful levels and present strategies to restore function to this tissue to ensure better treatment results.


Assuntos
Atrofia Muscular Espinal , Doenças Neuromusculares , Criança , Humanos , Atrofia Muscular Espinal/genética , Músculo Esquelético , Fenótipo , Fatores de Transcrição
5.
Sci Rep ; 13(1): 8410, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225865

RESUMO

Surveillance of influenza A viruses (IAVs) among migratory waterfowl is a first step in understanding the ecology, biology, and pathogenicity of IAVs. As part of the nationwide surveillance effort for IAVs in fowl in South Korea, we collected environmental fecal samples in different migratory bird stopover sites in South Korea during the winter seasons within November 2014 through January 2018. We collected a total of 6758 fecal samples, 75 of which were positive for IAV (1.11% positivity). Prevalence of IAVs varied per site and per year. Based on sequencing, the most prevalent hemagglutinin (HA) subtypes were H1, H6, and H5, and the most prevalent neuraminidase (NA) subtypes were N1, N3, and N2. Phylogenetic analyses showed that the genes we isolated clustered with reported isolates collected from other locations along the East Asian-Australasian Flyway. All the H5 and H7 isolates collected in this study were of low pathogenicity. None of the N1 and N2 genes carried amino acid markers of resistance against NA inhibitors. The winter 2016-2017 subset were primarily borne by migratory geese (Anser spp.). These results suggest that majority of the IAVs circulating among migratory wild fowl in South Korea in 2014-2018 were of low pathogenicity.


Assuntos
Anseriformes , Vírus da Influenza A , Influenza Aviária , Animais , Antivirais , Gansos/virologia , Vírus da Influenza A/genética , Vírus da Influenza A/patogenicidade , Filogenia , República da Coreia/epidemiologia , Influenza Aviária/diagnóstico , Influenza Aviária/epidemiologia , Influenza Aviária/genética , Influenza Aviária/virologia , Fezes/virologia , Anseriformes/virologia , Monitoramento Biológico
6.
Immune Netw ; 23(2): e13, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37179752

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is one of the most consequential global health crises in over a century. Since its discovery in 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to mutate into different variants and sublineages, rendering previously potent treatments and vaccines ineffective. With significant strides in clinical and pharmaceutical research, different therapeutic strategies continue to be developed. The currently available treatments can be broadly classified based on their potential targets and molecular mechanisms. Antiviral agents function by disrupting different stages of SARS-CoV-2 infection, while immune-based treatments mainly act on the human inflammatory response responsible for disease severity. In this review, we discuss some of the current treatments for COVID-19, their mode of actions, and their efficacy against variants of concern. This review highlights the need to constantly evaluate COVID-19 treatment strategies to protect high risk populations and fill in the gaps left by vaccination.

7.
Neuron ; 111(9): 1423-1439.e4, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36863345

RESUMO

Reduced survival motor neuron (SMN) protein triggers the motor neuron disease, spinal muscular atrophy (SMA). Restoring SMN prevents disease, but it is not known how neuromuscular function is preserved. We used model mice to map and identify an Hspa8G470R synaptic chaperone variant, which suppressed SMA. Expression of the variant in the severely affected mutant mice increased lifespan >10-fold, improved motor performance, and mitigated neuromuscular pathology. Mechanistically, Hspa8G470R altered SMN2 splicing and simultaneously stimulated formation of a tripartite chaperone complex, critical for synaptic homeostasis, by augmenting its interaction with other complex members. Concomitantly, synaptic vesicular SNARE complex formation, which relies on chaperone activity for sustained neuromuscular synaptic transmission, was found perturbed in SMA mice and patient-derived motor neurons and was restored in modified mutants. Identification of the Hspa8G470R SMA modifier implicates SMN in SNARE complex assembly and casts new light on how deficiency of the ubiquitous protein causes motor neuron disease.


Assuntos
Atrofia Muscular Espinal , Animais , Camundongos , Modelos Animais de Doenças , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Atrofia Muscular Espinal/patologia , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Sinapses/metabolismo , Transmissão Sináptica , Fatores de Transcrição/metabolismo
8.
Immune Netw ; 22(5): e42, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36381958

RESUMO

Vaccination with tumor peptide epitopes associated with MHC class I molecules is an attractive approach directed at inducing tumor-specific CTLs. However, challenges remain in improving the therapeutic efficacy of peptide epitope vaccines, including the low immunogenicity of peptide epitopes and insufficient stimulation of innate immune components in vivo. To overcome this, we aimed to develop and test an innovative strategy that elicits potent CTL responses against tumor epitopes. The essential feature of this strategy is vaccination using tumor epitope-loaded nanoparticles (NPs) in combination with polyinosinic-polycytidylic acid (poly-IC) and anti-PD1 mAb. Carboxylated NPs were prepared using poly(lactic-co-glycolic acid) and poly(ethylene/maleic anhydride), covalently conjugated with anti-H-2Kb mAbs, and then attached to H-2Kb molecules isolated from the tumor mass (H-2b). Native peptides associated with the H-2Kb molecules of H-2Kb-attached NPs were exchanged with tumor peptide epitopes. Tumor peptide epitope-loaded NPs efficiently induced tumor-specific CTLs when used to immunize tumor-bearing mice as well as normal mice. This activity of the NPs significantly was increased when co-administered with poly-IC. Accordingly, the NPs exerted significant anti-tumor effects in mice implanted with EG7-OVA thymoma or B16-F10 melanoma, and the anti-tumor activity of the NPs was significantly increased when applied in combination with poly-IC. The most potent anti-tumor activity was observed when the NPs were co-administered with both poly-IC and anti-PD1 mAb. Immunization with tumor epitope-loaded NPs in combination with poly-IC and anti-PD1 mAb in tumor-bearing mice can be a powerful means to induce tumor-specific CTLs with therapeutic anti-tumor activity.

9.
Biomaterials ; 290: 121859, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36306683

RESUMO

Alternatively activated or M2 macrophages, as opposed to the well characterized pro-inflammatory or M1 macrophages, vitally regulate anti-inflammation, wound healing, and tissue repair to maintain tissue homeostasis. Although ubiquitous presence of macrophages in diverse tissues, exposed to different physical environments, infers distinct immune responses of M2 macrophages with high phenotypic heterogeneity, the underlying mechanism of how the varying extracellular mechanical conditions alter their immunological activation remains unclear. Here, we demonstrate that M2 activation requires a threshold mechanical cue from the extracellular microenvironment, and matrix rigidity-dependent macrophage spreading is mediated by the F-actin formation that is essential to regulate mechanosensitive M2 activation of macrophages. We identified a new mechanosensing function of STAT6 (signal transducer and activator of transcription 6), a key transcription factor for M2 activation, whose intranuclear transportation is promoted by the rigid matrix that facilitates the F-actin formation. Our findings further highlight the critical role of mechanosensitive M2 activation of macrophages in long-term adaptation to the extracellular microenvironment by bridging nuclear mechanosensation and immune responses.


Assuntos
Actinas , Ativação de Macrófagos , Fator de Transcrição STAT6/metabolismo , Transporte Ativo do Núcleo Celular , Macrófagos
10.
BMC Cancer ; 22(1): 861, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933369

RESUMO

BACKGROUND: Tumor budding is associated with lymph node (LN) metastasis in submucosal colorectal cancer (CRC). However, the rate of LN metastasis associated with the number of tumor buds is unknown. Here, we determined the optimal tumor budding cut-off number and developed a composite scoring system (CSS) for estimating LN metastasis of submucosal CRC. METHODS: In total, 395 patients with histologically confirmed T1N0-2M0 CRC were evaluated. The clinicopathological characteristics were subjected to univariate and multivariate analyses. The Akaike information criterion (AIC) values of the multivariate models were evaluated to identify the optimal cut-off number. A CSS for LN metastasis was developed using independent risk factors. RESULTS: The prevalence of LN metastasis was 13.2%. Histological differentiation, lymphatic or venous invasion, and tumor budding were associated with LN metastasis in univariate analyses. In multivariate models adjusted for histological differentiation and lymphatic or venous invasion, the AIC value was lowest for five tumor buds. Unfavorable differentiation (odds ratio [OR], 8.16; 95% confidence interval [CI], 1.80-36.89), lymphatic or venous invasion (OR, 5.91; 95% CI, 2.91-11.97), and five or more tumor buds (OR, 3.01; 95% CI, 1.21-7.69) were independent risk factors. In a CSS using these three risk factors, the rates of LN metastasis were 5.6%, 15.5%, 31.0%, and 52.4% for total composite scores of 0, 1, 2, and ≥ 3, respectively. CONCLUSIONS: For the estimation of LN metastasis in submucosal CRC, the optimal tumor budding cut-off number was five. Our CSS can be utilized to estimate LN metastasis.


Assuntos
Neoplasias Colorretais , Vasos Linfáticos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Vasos Linfáticos/patologia , Invasividade Neoplásica/patologia , Razão de Chances , Estudos Retrospectivos , Fatores de Risco
11.
BMC Infect Dis ; 22(1): 530, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676650

RESUMO

BACKGROUND: Despite high vaccination coverage, measles outbreaks have been reported in measles elimination countries, especially among healthcare workers in their 20 and 30 s. This study was designed to identify measles-susceptible individuals and to evaluate whether primary or secondary vaccine failure occurred during measles outbreak response immunization (ORI) activities. METHODS: The study population was divided into three groups as follows: natural immunity group (Group 1), vaccine-induced immunity group (Group 2), and vaccine failure group (Group 3). We evaluated the immunogenicity of measles among healthcare workers using three methods-enzyme-linked immunoassays, plaque reduction neutralization tests, and avidity assays. The results were assessed at baseline, 4 weeks after, and 6 months after the completion of measles-mumps-rubella (MMR) vaccination. RESULTS: In total, 120 subjects were enrolled, with 40 subjects in each group. The median age of Group 3 was 29 years, which was significantly lower than that of the other groups. The baseline negative measles virus (MeV) IgG in Group 3 increased to a median value of 165 AU/mL at 4 weeks after ORI and was lower than that in Groups 1 and 2. The median neutralizing antibody titer was highest in Group 1, and this was significantly different from that in Group 2 or Group 3 at 4 weeks (944 vs. 405 vs. 482 mIU/mL, P = 0.001) and 6 months (826 vs. 401 vs. 470, P = 0.011) after ORI. The rates of high MeV avidity IgG were highest in Group 2, and these were significantly different from those in Groups 1 or 3 at 4 weeks (77.5 vs. 90% vs. 88.6%, P = 0.03) and 6 months (81 vs. 94.8 vs. 82.1%, P = 0.01) after ORI. CONCLUSIONS: Considering the MeV-neutralizing antibodies and IgG avidity after MMR vaccination in measles-susceptible group, vaccine failure is inferred as secondary vaccine failure, and further data regarding the maintenance of immunogenicity are needed based on long-term data. The MeV-neutralizing antibody levels were highest in the natural immunity group, and the primary vaccine-induced immunity group showed the highest rates of high MeV IgG avidity.


Assuntos
Sarampo , Caxumba , Rubéola (Sarampo Alemão) , Adulto , Anticorpos Neutralizantes , Anticorpos Antivirais , Surtos de Doenças , Pessoal de Saúde , Humanos , Imunização Secundária/métodos , Imunoglobulina G , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Sarampo-Caxumba-Rubéola , Caxumba/prevenção & controle , Rubéola (Sarampo Alemão)/prevenção & controle , Vacinação
12.
Pharmaceuticals (Basel) ; 15(5)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35631425

RESUMO

Plants contain underutilized resources of compounds that can be employed to combat viral diseases. Aloe vera (L.) Burm. f. (syn. Aloe barbadensis Mill.) has a long history of use in traditional medicine, and A. vera extracts have been reported to possess a huge breadth of pharmacological activities. Here, we discuss the potential of A. vera compounds as antivirals and immunomodulators for the treatment of viral diseases. In particular, we highlight the use of aloe emodin and acemannan as lead compounds that should be considered for further development in the management and prevention of viral diseases. Given the immunomodulatory capacity of A. vera compounds, especially those found in Aloe gel, we also put forward the idea that these compounds should be considered as adjuvants for viral vaccines. Lastly, we present some of the current limitations to the clinical applications of compounds from Aloe, especially from A. vera.

13.
Genes Genomics ; 44(3): 389-394, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35150400

RESUMO

BACKGROUND: Anorectal condyloma is the representative venereal disease caused by human papilloma virus (HPV), which has more 180 subtypes. Although there are various known risk factors for recurrence, few studies have investigated the influence of HPV subtypes. OBJECTIVE: We aimed to investigate the correlation between the recurrence of anorectal condyloma and HPV subtypes. METHODS: We analyzed the clinical and histopathological information of 143 patients who underwent surgery for anorectal condyloma at the National Medical Center between March 2016 and September 2020. PCR analyses were performed to confirm the HPV subtype in 24 patients. RESULTS: Recurrence was confirmed in 63 patients through outpatient follow-up over a median of 31.7 months (range: 0-56.2) after surgery. Recurrence was significantly associated with anorectal condyloma severity (p < 0.001), but there were no differences between the primary and recurrent groups, CD4-positive cell counts, or human immunodeficiency virus loads. The high-risk HPV subtype was associated with a high recurrence rate. Furthermore, the overall recurrence rate in anorectal condyloma patients was 44.1%. CONCLUSION: These results suggest that recurrence of anorectal condyloma has a significant association with high-risk HPV subtypes. Therefore, it is necessary to check for recurrences during follow-up after surgery.


Assuntos
Alphapapillomavirus , Condiloma Acuminado , Infecções por Papillomavirus , Condiloma Acuminado/complicações , Condiloma Acuminado/patologia , Condiloma Acuminado/cirurgia , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Fatores de Risco
14.
Pharmaceutics ; 15(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36678679

RESUMO

The Zika virus (ZIKV) remains a global health concern. Thus far, no antiviral or vaccine has been approved to prevent or treat ZIKV infection. In a previous study, we found that lipophilic statins can inhibit ZIKV production in Vero cells. These statins appear to have different potencies against ZIKV infection. Here, we determined whether combinations of statins would have synergistic effects to maximize the efficacy of the statins and to reduce potential side effects. Specifically, we used a modified fixed-ratio assay for the combinations of atorvastatin (ATO) or fluvastatin (FLU) with mevastatin (MEV) or simvastatin (SIM). All combinations with MEV tended towards synergy, especially with higher fractions of MEV in the combinations. The ATO + SIM combination tended towards additivity. The FLU + SIM combination also tended towards additivity except for one combination which had the highest fraction of FLU over SIM among the tested combinations. Overall, certain combinations of ATO or FLU with SIM or MEV may be synergistic. More exhaustive combinatorial assays in vitro and in vivo could help define whether combining lipophilic statins would be beneficial and safe for treating ZIKV infections.

15.
Sci Rep ; 11(1): 23991, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907256

RESUMO

Avian influenza viruses (AIVs) are carried by wild migratory waterfowl across migratory flyways. To determine the strains of circulating AIVs that may pose a risk to poultry and humans, regular surveillance studies must be performed. Here, we report the surveillance of circulating AIVs in South Korea during the winter seasons of 2009-2013. A total of 126 AIVs were isolated from 7942 fecal samples from wild migratory birds, with a total isolation rate of 1.59%. H1‒H7 and H9‒H11 hemagglutinin (HA) subtypes, and N1‒N3, N5, and N7‒N9 neuraminidase (NA) subtypes were successfully isolated, with H6 and N2 as the most predominant HA and NA subtypes, respectively. Sequence identity search showed that the HA and NA genes of the isolates were highly similar to those of low-pathogenicity influenza strains from the East Asian-Australasian flyway. No match was found for the HA genes of high-pathogenicity influenza strains. Thus, the AIV strains circulating in wild migratory birds from 2009 to 2013 in South Korea likely had low pathogenicity. Continuous surveillance studies such as this one must be performed to identify potential precursors of influenza viruses that may threaten animal and human health.


Assuntos
Aves/virologia , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Animais , República da Coreia/epidemiologia
16.
J Microbiol ; 59(11): 959-977, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34724178

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has underscored the lack of approved drugs against acute viral diseases. Plants are considered inexhaustible sources of drugs for several diseases and clinical conditions, but plant-derived compounds have seen little success in the field of antivirals. Here, we present the case for the use of compounds from vascular plants, including alkaloids, flavonoids, polyphenols, and tannins, as antivirals, particularly for the treatment of COVID-19. We review current evidence for the use of these phytochemicals against SARS-CoV-2 infection and present their potential targets in the SARS-CoV-2 replication cycle.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Pandemias , Compostos Fitoquímicos , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Chlorocebus aethiops , Células HEK293 , Humanos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Células Vero
17.
Polymers (Basel) ; 13(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34833243

RESUMO

This study reports the preparation of a polybutylene succinate (PBS) film reinforced with pure cellulose nanofibril (PCNF) and lignocellulose nanofibril (LCNF) by a two-step process that consists of solvent dispersion and twin-screw extrusion. Compared to the conventional one-step process, this method offered improved mechanical properties. The addition of 5% CNF increased the tensile properties up to 18.8%. Further, the effect of the lignin content was also studied by using LCNF as a reinforcement. The LCNF was prepared with and without a deep eutectic solvent (DES) pretreatment to gain LCNF with a lignin content that varied between 5, 19, and 30%. The mechanical properties results show that a 5% addition of LCNF to the PBS matrix increased its tensile strength and elastic modulus. Further, the morphological and thermal properties of the composites were also studied in detail.

18.
Polymers (Basel) ; 13(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34503015

RESUMO

Lignocellulose nanofibrils (LCNFs) with different lignin contents were prepared using choline chloride (ChCl)/lactic acid (LA), deep eutectic solvent (DES) pretreatment, and subsequent mechanical defibrillation. The LCNFs had a diameter of 15.3-18.2 nm, which was similar to the diameter of commercial pure cellulose nanofibrils (PCNFs). The LCNFs and PCNFs were wet-spun in CaCl2 solution for filament fabrication. The addition of sodium alginate (AL) significantly improved the wet-spinnability of the LCNFs. As the AL content increased, the average diameter of the composite filaments increased, and the orientation index decreased. The increase in AL content improved the wet-spinnability of CNFs but deteriorated the tensile properties. The increase in the spinning rate resulted in an increase in the orientation index, which improved the tensile strength and elastic modulus.

19.
Polymers (Basel) ; 13(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34503030

RESUMO

In this study, cellulose acetate (CA)/cellulose nanofibril (CNF) film was prepared via solvent casting. CNF was used as reinforcement to increase tensile properties of CA film. CNF ratio was varied into 3, 5, and 10 phr (parts per hundred rubbers). Triacetin (TA) and triethyl citrate (TC) were used as two different eco-friendly plasticizers. Two different types of solvent, which are acetone and N-methyl-2-pyrrolidone (NMP), were also used. CA/CNF film was prepared by mixing CA and CNF in acetone or NMP with 10% concentration and stirred for 24 h. Then, the solution was cast in a polytetrafluoroethylene (PTFE) dish followed by solvent evaporation for 12 h at room temperature for acetone and 24 h at 80 °C in an oven dryer for NMP. The effect of solvent type, plasticizers type, and CNF amount on film properties was studied. Good dispersion in NMP was evident from the morphological study of fractured surface and visible light transmittance. The results showed that CNF has a better dispersion in NMP which leads to a significant increase in tensile strength and elastic modulus up to 38% and 65%, respectively, compared with those of neat CA. CNF addition up to 5 phr loading increased the mechanical properties of the film composites.

20.
Medicine (Baltimore) ; 100(35): e27042, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477135

RESUMO

ABSTRACT: To investigate the feasibility, safety, and outcomes of three-dimensional (3D) laparoscopic vaginoplasty with a rectosigmoid colon flap for vaginal reconstruction.Following appropriate preoperative patient counseling, 17 consecutive patients underwent vaginoplasty using a 3D laparoscopic system. Perioperative and postoperative outcomes were retrospectively evaluated.Between September 2016 and February 2020, 17 patients underwent 3D laparoscopic vaginoplasty with a rectosigmoid colon flap. Of them, 15 (88%) were transgender female patients, and 2 (12%) were cisgender female patients with congenital deformities. Among the 15 transgender patients, 12 (80%) underwent de novo surgeries and 3 (20%) underwent re-do surgeries. The mean age at the time of operation was 33.0 years, and the mean total operation time was 529 ±â€Š128 minutes. The initial intraoperative mean vaginal depth was 15.2 ±â€Š1.3 cm, and the 30-day readmission rate was 5.9% (1/17 cases). The mean follow-up duration was 24.8 months.Perioperative and postoperative outcomes suggest that 3D laparoscopic rectosigmoid colon vaginoplasty is a potentially acceptable, effective, and safe method for vaginal reconstruction.


Assuntos
Laparoscopia/métodos , Cirurgia de Readequação Sexual/métodos , Retalhos Cirúrgicos/cirurgia , Vagina/cirurgia , Adulto , Feminino , Humanos , Laparoscopia/estatística & dados numéricos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Estudos Retrospectivos , Cirurgia de Readequação Sexual/estatística & dados numéricos , Pessoas Transgênero/estatística & dados numéricos , Vagina/fisiopatologia
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