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1.
Small ; 20(35): e2311895, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38660823

RESUMO

The conformation of molecules and materials is crucial in determining their properties and applications. Here, this work explores the reversible transformation between two distinct conformational isomers in metal nanoclusters. This work demonstrates the successful manipulation of a controllable and reversible isomerization of Au18SR14 within an aqueous solution through two distinct methods: ethanol addition and pH adjustment. The initial driver is the alteration of the solution environment, leading to the aggregation of Au18SR14 protected by ligands with smaller steric hindrance. At the atomic level, the folding mode of the unique Au4SR5 staple underpins the observed structural transformation. The reversal of staple conformation leads to color shifting between green and orange-red, and tailors a second emission peak at 725 nm originating from charge transfer from the thiolate to the Au9 core. This work not only deepens the understanding of the surface structure and dual-emission of metal nanoparticles, but also enhances the comprehension of their isomerization.

2.
Pharmacol Res ; 203: 107137, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522761

RESUMO

Peptide stapling, by employing a stable, preformed alpha-helical conformation, results in the production of peptides with improved membrane permeability and enhanced proteolytic stability, compared to the original peptides, and provides an effective solution to accelerate the rapid development of peptide drugs. Various reviews present peptide stapling chemistries, anchoring residues and one- or two-component cyclization, however, therapeutic stapled peptides have not been systematically summarized, especially focusing on various disease-related targets. This review highlights the latest advances in therapeutic peptide drug development facilitated by the application of stapling technology, including different stapling techniques, synthetic accessibility, applicability to biological targets, potential for solving biological problems, as well as the current status of development. Stapled peptides as therapeutic drug candidates have been classified and analysed mainly by receptor- and ligand-based stapled peptide design against various diseases, including cancer, infectious diseases, inflammation, and diabetes. This review is expected to provide a comprehensive reference for the rational design of stapled peptides for different diseases and targets to facilitate the development of therapeutic peptides with enhanced pharmacokinetic and biological properties.


Assuntos
Peptídeos , Humanos , Animais , Peptídeos/uso terapêutico , Peptídeos/química , Peptídeos/farmacologia , Desenho de Fármacos
3.
Photochem Photobiol Sci ; 23(6): 1179-1194, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38771468

RESUMO

In this study, photostability and photodynamic antimicrobial performance of dye extracts from Hibiscus sabdariffa (HS) calyces, Sorghum bicolor (SB) leaf sheaths, Lawsonia inermis (LI) leaves and Curcuma longa (CL) roots were investigated in Acetate-HCl (AH) Buffer (pH 4.6), Tris Base-HCl (TBH) Buffer (pH 8.6), distilled water (dH2O), and Phosphate Buffer Saline (PBS, pH 7.2) using Bacillus subtilis as model for gram positive bacteria, Escherichia coli as model for gram negative bacteria, phage MS2 as model for non-envelope viruses and phage phi6 as model for envelope viruses including SARS CoV-2 which is the causative agent of COVID-19. Our results showed that the photostability of the dye extracts is in the decreasing order of LI > CL > SB > HS. The dye extract-HS is photostable in dH2O but bleaches in buffers-AH, TBH and PBS. The rate of bleaching is higher in AH compared to in TBH and PBS. The bleaching and buffers affected the photodynamic and non-photodynamic antimicrobial activity of the dye extracts. The photodynamic antibacterial activity of the dye extracts is in the decreasing order of CL > HS > LI > SB while the non-photodynamic antibacterial activity is in the decreasing order of LI > CL > HS > SB. The non-photodynamic antiviral activity pattern observed is the same as that of non-photodynamic antibacterial activity observed. However, the photodynamic antiviral activity of the dye extracts is in the decreasing order of CL > LI > HS > SB. Given their performance, the dye extracts maybe mostly suitable for environmental applications including fresh produce and food disinfection, sanitation of hands and contact surfaces where water can serve as diluent for the extracts and the microenvironment is free of salts.


Assuntos
Extratos Vegetais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sorghum/química , Hibiscus/química , Curcuma/química , Escherichia coli/efeitos dos fármacos , Levivirus/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Bacillus subtilis/efeitos dos fármacos , Desinfecção , Antibacterianos/farmacologia , Antibacterianos/química , SARS-CoV-2/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Corantes/química , Corantes/farmacologia , COVID-19 , Folhas de Planta/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Luz
4.
BMC Gastroenterol ; 24(1): 112, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491416

RESUMO

PURPOSE: Rectal anastomoses have a persisting high incidence of anastomotic leakage. This study aimed to assess whether the use of a poly-ϵ-caprolactone (PCL) scaffold as reinforcement of a circular stapled rectal anastomosis could increase tensile strength and improve healing compared to a control in a piglet model. METHOD: Twenty weaned female piglets received a stapled rectal anastomosis and were randomised to either reinforcement with PCL scaffold (intervention) or no reinforcement (control). On postoperative day five the anastomosis was subjected to a tensile strength test followed by a histological examination to evaluate the wound healing according to the Verhofstad scoring. RESULTS: The tensile strength test showed no significant difference between the two groups, but histological evaluation revealed significant impaired wound healing in the intervention group. CONCLUSION: The incorporation of a PCL scaffold into a circular stapled rectal anastomosis did not increase anastomotic tensile strength in piglets and indicated an impaired histologically assessed wound healing.


Assuntos
Fístula Anastomótica , Caproatos , Lactonas , Grampeamento Cirúrgico , Animais , Feminino , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/etiologia , Reto/cirurgia , Suínos
5.
Surg Endosc ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218833

RESUMO

BACKGROUND: Sleeve gastrectomy is the most performed bariatric surgery. Post-operative gastric sleeve leaks, although rare, are dreaded complications. This study aims to perform an updated investigation of the factors associated with sleeve leaks. METHODS: This retrospective cohort study analyzed 692,554 cases from the MBSAQIP database (2016-2021) with CPT code 43,775 for primary sleeve gastrectomy. We excluded emergency operations, conversions/revisions, endoscopic interventions, patient with prior foregut surgery, and open operations. Multivariate logistic regression analysis (STATA version 15) was performed to identify factors associated with sleeve gastrectomy leaks. RESULTS: Out of 692,554 patients, 600,910 (86.77%) patients underwent laparoscopic sleeve gastrectomy, and 91,644 (13.23%) patients underwent robotic sleeve gastrectomy. 1179 (0.17%) developed leaks within 30 days; 177(0.19%) were in the robotic group and 1002 (0.17%) in the laparoscopic group with no significant difference in leak rates between two groups on multivariate analysis. Black patients had lower odds of having leaks as compared to white patients (Odds Ratio (OR): 0.68 (0.56-0.82); p < 0.01). Hispanic patients had lower odds of having leak as compared to non-Hispanics. Factors associated with higher leak odds (p < 0.05) included hypertension, GERD, smoking, immunosuppression, increased operating time, and albumin < 3.5 g/dl. Higher odds of leaks were observed in years 2016-2019 vs 2020-2021 (OR: 1.44 (1.25-1.65), p < 0.01). Higher odds of leak in operations with general surgeons compared to bariatric surgeons was found (OR: 1.46 (1.04-2.02), p = 0.02); observed only on robotic group on subgroup analysis (OR: 2.2 (1.2-4.2), p = 0.02). Staple line reinforcement, oversewing, and performance of leak test showed no differences in leak rate. Bougie size and distance from pylorus were not associated with changes in leak rate. CONCLUSION: This study provides updated insights into the factors associated with sleeve leaks, reinforcing information gained from prior studies. A higher association of leak among general surgeons could represent a learning curve for new robotic general surgeons. The overall decreasing trend for gastric sleeve leak is encouraging and may be a sign of improved techniques.

6.
Surg Endosc ; 38(5): 2894-2899, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38630177

RESUMO

BACKGROUND: Leaks following bariatric surgery, while rare, are potentially fatal due to risk of peritonitis and sepsis. Anastomotic leaks and gastro-gastric fistulae following Roux-En-Y gastric bypass (RYGB) as well as staple line leaks after sleeve gastrectomy have historically been treated multimodally with surgical drainage, aggressive antibiotic therapy, and more recently, endoscopically. Endoscopic clipping using over-the-scope clips and endoscopic suturing are two of the most common approaches used to achieve full thickness closure. METHODS: A systematic literature search was performed in PubMed to identify articles on the use of endoscopic clipping or suturing for the treatment of leaks and fistulae following bariatric surgery. Studies focusing on stents, and those that incorporated multiple closure techniques simultaneously, were excluded. Literature review and meta-analysis were performed with the PRISMA guidelines. RESULTS: Five studies with 61 patients that underwent over-the-scope clip (OTSC) closure were included. The pooled proportion of successful closure across the studies was 81.1% (95% CI 67.3 to 91.7). The successful closure rates were homogeneous (I2 = 39%, p = 0.15). Three studies with 92 patients that underwent endoscopic suturing were included. The weighted pooled proportion of successful closure across the studies was shown to be 22.4% (95% CI 14.6 to 31.3). The successful closure rates were homogeneous (I2 = 0%, p = 0.44). Three of the studies, totaling 34 patients, examining OTSC deployment reported data for reintervention rate. The weighted pooled proportion of reintervention across the studies was 35.0% (95% CI 11.7 to 64.7). We noticed statistically significant heterogeneity (I2 = 68%, p = 0.04). One study, with 20 patients examining endoscopic suturing, reported rate of repeat intervention 60%. CONCLUSION: Observational reports show that patients managed with OTSC were more likely to experience healing of their defect than those managed with endoscopic suturing. Larger controlled studies comparing different closure devices for bariatric leaks should be carried out to better understand the ideal endoscopic approach to these complications.


Assuntos
Fístula Anastomótica , Cirurgia Bariátrica , Humanos , Fístula Anastomótica/etiologia , Cirurgia Bariátrica/métodos , Cirurgia Bariátrica/efeitos adversos , Técnicas de Sutura/instrumentação , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Fístula Gástrica/etiologia , Fístula Gástrica/cirurgia , Técnicas de Fechamento de Ferimentos
7.
Phytopathology ; 114(3): 521-537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37831969

RESUMO

The use of biocontrol agents (BCAs) coping with fungal pathogens causing Fusarium head blight (FHB) is a compelling strategy for disease management, but a better elucidation of their effectiveness is crucial. Meta-analysis is the analysis of the results of multiple studies, which is typically performed to synthesize evidence from many possible sources in a formal probabilistic manner. This meta-analytic study, including 30 pathometric, biometric, physiochemical, genetic, and mycotoxin response variables reported in 56 studies, evidences the BCA effects on FHB in wheat. The effectiveness of BCAs of FHB in wheat in terms of pathogen abundance and disease reductions, biomass and yield conservation, and mycotoxin prevention/control was confirmed. BCAs showed higher efficacy (i) in studies published more recently; (ii) under controlled conditions; (iii) in high susceptible wheat cultivars; (iv) when Fusarium inoculation and BCA treatment did not occur directly on the plant (i.e., at the seed and kernel levels) in terms of disease development and mycotoxin control, and vice versa in terms of biomass conservation; (v) if Fusarium inoculation and BCA treatment occurred by spraying spikes in terms of yield; (vi) at 15 to 21 days post Fusarium inoculation or BCA treatment; and (vii) if they were filamentous fungi. However, BCAs overall were less efficacious than conventional agrochemicals, especially in terms of pathogen abundance and FHB reductions, as well as of mycotoxin prevention/control, although inconsistencies were reported among the investigated moderator variables. This study also highlights the complexity of reaching a good balance among BCA effects, and the need for further research.


Assuntos
Fusarium , Micotoxinas , Triticum/microbiologia , Fusarium/fisiologia , Doenças das Plantas/microbiologia
8.
Surg Today ; 54(1): 23-30, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37127776

RESUMO

PURPOSE: While laparoscopic pelvic exenteration reduces intraoperative blood loss, dorsal venous complex bleeding during this procedure causes issues. We previously introduced a method to transect the dorsal venous complex and urethra using a linear stapler during cooperative laparoscopic and transperineal endoscopic (two-team) pelvic exenteration. The present study assessed its effectiveness in reducing intraoperative blood loss by comparing it with conventional laparoscopic pelvic exenteration. METHODS: This retrospective cohort study was conducted at a Japanese tertiary referral center. Eleven cases of two-team laparoscopic pelvic exenteration with staple transection of the dorsal venous complex (T-PE group) were compared to 25 cases of conventional laparoscopic pelvic exenteration (C-PE group). The primary outcome measure was intraoperative blood loss. RESULTS: There were no significant between-group differences in patient background. The mean intraoperative blood loss was significantly lower in the T-PE group than in the C-PE group (200 vs. 850 mL, p = 0.01). The respective mean operation time, postoperative complication rate, and R0 resection rate were similar between the T-PE and C-PE groups (636 min vs. 688 min, p = 0.36; 36% vs. 44%, p = 0.65; 100% vs. 100%, p = 1.00). CONCLUSIONS: Two-team laparoscopic pelvic exenteration with staple transection of the dorsal venous complex reduced intraoperative blood loss from the dorsal venous complex in a technically safe and oncologically feasible manner.


Assuntos
Laparoscopia , Exenteração Pélvica , Humanos , Exenteração Pélvica/métodos , Perda Sanguínea Cirúrgica/prevenção & controle , Uretra , Estudos Retrospectivos , Laparoscopia/métodos
9.
Surg Today ; 54(7): 779-786, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38381178

RESUMO

PURPOSE: To evaluate the safety and efficacy of new staple-line reinforcement (SLR) in pulmonary resection through a prospective study and to compare the results of this study with historical control data in an exploratory study. METHODS: The subjects of this study were 48 patients who underwent thoracoscopic lobectomy. The primary endpoint was air leakage from the staple line. The secondary endpoints were the location of air leakage, duration of air leakage, and postoperative pulmonary complications. RESULTS: The incidence of intraoperative air leakage from the staple line was 6.3%. Three patients had prolonged air leakage as a postoperative pulmonary complication. No malfunction was found in patients who underwent SLR with the stapling device. When compared with the historical group, the SLR group had a significantly lower incidence of air leakage from the staple line (6.3% vs. 28.5%, P < 0.001) and significantly shorter indwelling chest drainage time (P = 0.049) and length of hospital stay (P < 0.001). CONCLUSIONS: The use of SLR in pulmonary resection was safe and effective. When compared with conventional products, SLR could control intraoperative air leakage from the staple line and shorten time needed for indwelling chest drainage and the length of hospital stay.


Assuntos
Tempo de Internação , Pneumonectomia , Complicações Pós-Operatórias , Grampeamento Cirúrgico , Humanos , Pneumonectomia/métodos , Estudos Prospectivos , Feminino , Masculino , Grampeamento Cirúrgico/métodos , Idoso , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Toracoscopia/métodos , Complicações Intraoperatórias/prevenção & controle , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Adulto , Incidência , Segurança , Fatores de Tempo
10.
Tech Coloproctol ; 28(1): 30, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321328

RESUMO

BACKGROUND: Low anterior resection in patients with rectal cancer may require a defunctioning loop ileostomy formation that requires closure after a period of time. There are three common techniques for ileostomy closure: anterior repair (AR or fold-over closure), resection and hand-sewn anastomosis (RHA), and resection and stapled anastomosis (RSA). We aimed to compare them on the basis of operative and postoperative features. METHODS: Patients with rectal cancer who underwent low anterior resection without complications were included in this study and randomly assigned to three parallel groups to undergo loop ileostomy closure via either AR, RHA, or RSA. Early and late outcomes were gathered from all included patients. RESULTS: Among 93 patients with a mean age of 56.21 ± 11.78 years, consisting of 58 (62.4%) men, 31 patients underwent AR, 30 patients RHA, and 32 patients RSA. There was no significant difference among the groups regarding the frequency and location of intraoperative injuries (P = 0.157). The AR groups demonstrated significantly less consumption of gauzes following intraoperative bleeding compared to the two others groups. The results showed that the duration of surgery in the RSA was significantly shorter than in the AR or RHA group (both P < 0.001). Regarding postoperative course, only one case of hematoma and two cases of surgical wound infection occurred in the RHA group. Anastomotic leakage and complete or partial obstruction did not occur in any group of patients. Latent postoperative complications did not occur in any group of patients. The median time between surgery and discharge as well as the interval until first gas passage, first defecation, oral tolerated liquid diet, as well as oral tolerated soft and regular diet in the AR group were significantly lower than in the two other groups (both P < 0.001). However, there was no statistical difference in these intervals between the RHA and RSA groups. CONCLUSIONS: Resection and stapled anastomosis had the shortest duration among the three techniques; however, anterior repair had faster recovery, including earlier tolerated oral diet, gas passing and defecation, and discharge, in comparison with the other techniques. TRIAL REGISTRATION: Trial registration number IRCT20120129008861N5.


Assuntos
Ileostomia , Neoplasias Retais , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Ileostomia/efeitos adversos , Técnicas de Sutura/efeitos adversos , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Neoplasias Retais/cirurgia , Complicações Pós-Operatórias/etiologia
11.
J Orthop Sci ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38519380

RESUMO

BACKGROUND: Arthroscopic ankle arthrodesis (AAA) has become popular because of its higher rate of bone union, lower invasiveness, and shorter hospital stays compared to those of open arthrodesis. However, postoperative malalignment is often observed for severe varus deformity, which can cause nonunion, pain, and adjacent joint arthrosis. A compression staple can provide a persistent, strong compressive force on the bone surface. This study aimed to clarify the difference in alignment correction in AAA by comparing a compression staple and screws fixation with screws-only fixation pre- and postoperatively. METHODS: Seventy ankles in 67 patients undergoing AAA were retrospectively reviewed. AAA with three screws through the distal tibia was performed in 53 ankles, and 17 ankles underwent AAA with a compression staple and two screws. After the preparation of the joint surface arthroscopically, patients in the S group had three canulated cancellous screws inserted through the medial tibia. Patients in the CS group had a compression staple placed at the lateral aspect of the tibiotalar joint and two screws inserted through the medial side. Clinical scores and pre-and postoperative alignment on plain radiographs were compared between the two procedures. RESULTS: There were no significant differences in the pre-and postoperative Japanese Society for Surgery of the Foot scale. One ankle in the S group exhibited nonunion. There were no significant differences in talar tilt and tibiotalar angles between the groups. The tibial plafond angle in the CS group was significantly lower than that in the S group (p < 0.05). Postoperatively, talar tilt and tibiotalar angles on the coronal image, and the lateral tibiotalar angle in the CS group were significantly lower than those in the S group (p < 0.05). CONCLUSION: AAA with a compression staple and two-screw fixations could obtain more optimal alignments than AAA with screw-only fixation, even in cases with severe varus deformity.

12.
Int J Mol Sci ; 25(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38892244

RESUMO

Endophytic fungi are present in every plant, and crops are no exception. There are more than 50,000 edible plant species on the planet, but only 15 crops provide 90 percent of the global energy intake, and "the big four"-wheat, rice, maize and potato-are staples for about 5 billion people. Not only do the four staple crops contribute to global food security, but the endophytic fungi within their plant tissues are complex ecosystems that have been under scrutiny. This review presents an outline of the endophytic fungi and their secondary metabolites in four staple crops: wheat, rice, maize and potato. A total of 292 endophytic fungi were identified from the four major crops, with wheat having the highest number of 157 endophytic fungi. Potato endophytic fungi had the highest number of secondary metabolites, totaling 204 compounds, compared with only 23 secondary metabolites from the other three crops containing endophytic fungi. Some of the compounds are those with specific structural and pharmacological activities, which may be beneficial to agrochemistry and medicinal chemistry.


Assuntos
Produtos Agrícolas , Endófitos , Fungos , Metabolismo Secundário , Endófitos/metabolismo , Produtos Agrícolas/microbiologia , Fungos/metabolismo , Triticum/microbiologia , Zea mays/microbiologia , Oryza/microbiologia , Solanum tuberosum/microbiologia
13.
Int J Mol Sci ; 25(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38673976

RESUMO

Antagonist peptides (ANTs) of vasoactive intestinal polypeptide receptors (VIP-Rs) are shown to enhance T cell activation and proliferation in vitro, as well as improving T cell-dependent anti-tumor response in acute myeloid leukemia (AML) murine models. However, peptide therapeutics often suffer from poor metabolic stability and exhibit a short half-life/fast elimination in vivo. In this study, we describe efforts to enhance the drug properties of ANTs via chemical modifications. The lead antagonist (ANT308) is derivatized with the following modifications: N-terminus acetylation, peptide stapling, and PEGylation. Acetylated ANT308 exhibits diminished T cell activation in vitro, indicating that N-terminus conservation is critical for antagonist activity. The replacement of residues 13 and 17 with cysteine to accommodate a chemical staple results in diminished survival using the modified peptide to treat mice with AML. However, the incorporation of the constraint increases survival and reduces tumor burden relative to its unstapled counterpart. Notably, PEGylation has a significant positive effect, with fewer doses of PEGylated ANT308 needed to achieve comparable overall survival and tumor burden in leukemic mice dosed with the parenteral ANT308 peptide, suggesting that polyethylene glycol (PEG) incorporation enhances longevity, and thus the antagonist activity of ANT308.


Assuntos
Leucemia Mieloide Aguda , Receptores de Peptídeo Intestinal Vasoativo , Animais , Camundongos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Receptores de Peptídeo Intestinal Vasoativo/metabolismo , Receptores de Peptídeo Intestinal Vasoativo/antagonistas & inibidores , Humanos , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linhagem Celular Tumoral
14.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38928023

RESUMO

We analyzed the thermal stability of the BstHPr protein through the site-directed point mutation Lys62 replaced by Ala residue using molecular dynamics simulations at five different temperatures: 298, 333, 362, 400, and 450 K, for periods of 1 µs and in triplicate. The results from the mutant thermophilic BstHPrm protein were compared with those of the wild-type thermophilic BstHPr protein and the mesophilic BsHPr protein. Structural and molecular interaction analyses show that proteins lose stability as temperature increases. Mutant and wild-type proteins behave similarly up to 362 K. However, at 400 K the mutant protein shows greater structural instability, losing more buried hydrogen bonds and exposing more of its non-polar residues to the solvent. Therefore, in this study, we confirmed that the salt bridge network of the Glu3-Lys62-Glu36 triad, made up of the Glu3-Lys62 and Glu36-Lys62 ion pairs, provides thermal stability to the thermophilic BstHPr protein.


Assuntos
Simulação de Dinâmica Molecular , Estabilidade Proteica , Ligação de Hidrogênio , Temperatura , Mutação , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Substituição de Aminoácidos , Conformação Proteica , Mutagênese Sítio-Dirigida
15.
N Z Vet J ; 72(5): 265-274, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38777331

RESUMO

AIM: To compare the biomechanical properties of three different sternal closure techniques in a 3D-printed bone model of a sternum from a 30-kg dog. METHODS: Median sternotomy was performed on a total of 90 three-dimensional (3D) copies of a polycarbonate (PC) model of a sternum, generated from the CT images of the sternum of a 30-kg German Shepherd dog. Three different methods were used to repair the sternotomies: polydioxanone suture (group PDS, n = 30), stainless steel bone staples (group SS, n = 30), and nitinol bone staples (group NS, n = 30). Each repair method was tested by applying tensile force in one of three ways (longitudinally, laterally, or torsionally) resulting in a sample size of n = 10 for each repair method-loading combination. In all experiments, the loads at 1-mm and 2-mm gap formation, failure, and the displacement at the failure point were measured. RESULTS: In lateral distraction and longitudinal shear tests, NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria (1 and 2 mm). NS exhibited significantly greater failure load than PDS. In torsion tests, NS required significantly greater application of force compared to SS or PDS at all displacement criteria (1 and 2 mm) and exhibited a greater failure load than PDS. In terms of displacement at failure point, PDS suture showed more displacement than SS or NS across all experiments (laterally, longitudinally, torsionally). CONCLUSIONS: In this study, bone staples were mechanically superior to PDS suture in median sternotomy closure using 3D-printed bone model in terms of 1-mm, 2-mm displacement loads, and displacement at failure. NS had a higher failure load than PDS under lateral, longitudinal, and torsional distraction. CLINICAL RELEVANCE: These study results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs.


Assuntos
Impressão Tridimensional , Esternotomia , Suturas , Animais , Suturas/veterinária , Cães , Fenômenos Biomecânicos , Esternotomia/veterinária , Esternotomia/métodos , Grampeamento Cirúrgico/veterinária , Grampeamento Cirúrgico/métodos , Grampeamento Cirúrgico/instrumentação , Esterno/cirurgia , Modelos Anatômicos , Técnicas de Sutura/veterinária
16.
Foot Ankle Surg ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38839459

RESUMO

BACKGROUND: The objective of this study was to evaluate the biomechanical stability of a medially placed nitinol staple compared to two crossed-screws in the first TMT-1 joint fusion in a cadaveric cyclic loading model. METHODS: Seven matched pairs (N = 7) of lower limb cadaveric specimens were utilized. TMT-1 joints from each donor were fixed with a medially placed nitinol staple or dorsally placed two 3.5 mm partially threaded cannulated crossed-screws. Specimens were tested in a 4-point bending setting with increasing cyclic forces. RESULTS: The mean plantar gapping was not significantly different between the two groups at any loading stage below 200 N. Specimens fixed with a nitinol staple failed at a mean load of 305 ± 57 N. Conversely, those fixed with crossed-screws failed at 373 ± 86 N. (P = .09). CONCLUSION: There was no statistical difference between a medially placed nitinol staple and dorsally placed crossed-screws in failure loads and plantar gapping under cyclic loads at the TMT-1 joint, however, the staple fixation was much more variable. LEVEL OF EVIDENCE: Level V, basic science study, biomechanics.

17.
J Transl Med ; 21(1): 88, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747298

RESUMO

BACKGROUND: Little is known on the association of types of grains with mortality and the moderating effect of lifestyle on this association. This study aims to evaluate the single or joint associations of types of grains and lifestyle with all-cause mortality among Chinese older adults. METHODS: Data were derived from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 1998 to 2018. Subjects aged ≥ 65 years were eligible. The types of grains included wheat, total rice, and coarse cereals. Lifestyle was derived using smoking, alcohol consumption, physical activity, and dietary pattern. All-cause mortality was the primary outcome. RESULTS: This study included 30275 participants with a mean age 87 ± 11 years and documented 19261 deaths during a mean follow-up of 4.8 years. Compared to wheat, in those with healthy and intermediate lifestyle, total rice was associated with a 13% (HR: 0.87, 95% CI 0.80, 0.93) and 6% (HR: 0.94, 95% CI 0.90, 1.00) lower risk of mortality, respectively, and coarse cereals were associated with a 14% (HR: 0.86, 95% CI 0.74, 1.00) and 12% (HR: 0.88, 95% CI 0.79, 0.97) lower risk of mortality, respectively. Meanwhile, an increase per SD in intakes of wheat and coarse cereals was associated with a 10% (HR: 1.10, 95% CI 1.03, 1.18) and 25% (HR: 1.25, 95% CI 1.08, 1.44) higher mortality rate in those with healthy lifestyle, and a 13% (HR: 1.13, 95% CI 1.08, 1.19) and 29% (HR: 1.29, 95% CI 1.17, 1.44) higher mortality in females but not males. In addition, a U-shaped association of intake of total grains with all- cause mortality was observed (P for non-linearity = 0.002), and a J-shaped association of intake of total rice with all- cause mortality was observed (P for non-linearity = 0.003). CONCLUSIONS: Specific types of grains and lifestyle were separately or jointly associated with all-cause mortality. Compared to wheat, total rice and coarse cereals were advanced grains for participants with a relatively healthy lifestyle. Intake of total rice was related to all-cause mortality in a dose-response manner. Therefore, a combination of intermediate intake of total rice and healthy lifestyle should be encouraged in older adults.


Assuntos
Dieta , População do Leste Asiático , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Estudos Prospectivos , Estudos Longitudinais , Estilo de Vida , Grão Comestível , Fatores de Risco
18.
J Pept Sci ; 29(7): e3478, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36633503

RESUMO

Insulin is a peptide responsible for regulating the metabolic homeostasis of the organism; it elicits its effects through binding to the transmembrane insulin receptor (IR). Insulin mimetics with agonistic or antagonistic effects toward the receptor are an exciting field of research and could find applications in treating diabetes or malignant diseases. We prepared five variants of a previously reported 20-amino acid insulin-mimicking peptide. These peptides differ from each other by the structure of the covalent bridge connecting positions 11 and 18. In addition to the peptide with a disulfide bridge, a derivative with a dicarba bridge and three derivatives with a 1,2,3-triazole differing from each other by the presence of sulfur or oxygen in their staples were prepared. The strongest binding to IR was exhibited by the peptide with a disulfide bridge. All other derivatives only weakly bound to IR, and a relationship between increasing bridge length and lower binding affinity can be inferred. Despite their nanomolar affinities, none of the prepared peptide mimetics was able to activate the insulin receptor even at high concentrations, but all mimetics were able to inhibit insulin-induced receptor activation. However, the receptor remained approximately 30% active even at the highest concentration of the agents; thus, the agents behave as partial antagonists. An interesting observation is that these mimetic peptides do not antagonize insulin action in proportion to their binding affinities. The compounds characterized in this study show that it is possible to modulate the functional properties of insulin receptor peptide ligands using disulfide mimetics.


Assuntos
Insulina , Receptor de Insulina , Insulina/metabolismo , Dissulfetos/química , Peptídeos/química
19.
Surg Endosc ; 37(2): 1401-1411, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35701675

RESUMO

BACKGROUND: Robot-assisted sleeve gastrectomy (RSG) is an increasingly common approach to sleeve gastrectomy (SG). Staple line reinforcement (SLR) is well-discussed in laparoscopic SG literature, but not RSG- likely due to the absence of dedicated robotic SLR devices. However, most RSG cases report SLR. This retrospective analysis compares outcomes in RSG cases reporting (1) any staple line treatment (SLT) vs none and (2) SLR vs oversewing. METHODS: MBSAQIP was queried for adults who underwent RSG from 2015 to 2019. Open procedures, Natural Orifice Transluminal Endoscopic Surgery, hand-assisted, single-incision, concurrent procedures, and illogical BMIs were excluded (n = 3444). Final sample included 52,354 patients. Two comparisons were made: SLT (n = 34,886) vs none (n = 17,468) and SLR (n = 22,217) vs oversew (n = 5620). We fitted multivariable regression models to estimate risk ratios (RR) and 95% confidence intervals (CI) and performed propensity score analysis with inverse probability of treatment weight based on patient factors. RESULTS: Most RSG cases utilized SLT (66.6%). Cases with SLT had a reduced risk of organ space SSI (RR 0.68 [0.49, 0.94]), 30-day reoperation (RR 0.77 [0.64, 0.93]), 30-day re-intervention (RR 0.80 [0.67, 0.96]), sepsis (RR 0.58 [0.35, 0.96]), unplanned intubation (RR 0.59 [0.37, 0.93]), extended ventilator use (RR 0.46 [0.23, 0.91]), and renal failure (RR 0.40 [0.19, 0.82]) compared to no-treatment cases. In single-treatment cases (n = 27,837), most utilized SLR (79.8%). Cases with oversew had a higher risk of any SSI (RR 1.70 [1.19, 2.42]), superficial incisional SSI (RR 1.71 [1.06, 2.76]), septic shock (RR 6.47 [2.11, 19.87]), unplanned intubation (RR 2.18 [1.06, 4.47]), and extended ventilator use (> 48 h) (RR 4.55 [1.63, 12.71]) than SLR. CONCLUSIONS: Our data suggest SLT in RSG is associated with reduced risk of some adverse outcomes vs no-treatment. Among SLT, SLR demonstrated lower risk than oversewing. However, risk of all-cause mortality, cardiac arrest, and unplanned ICU admission were not significant.


Assuntos
Laparoscopia , Obesidade Mórbida , Procedimentos Cirúrgicos Robóticos , Robótica , Adulto , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Pontuação de Propensão , Obesidade Mórbida/cirurgia , Grampeamento Cirúrgico/métodos , Laparoscopia/métodos , Gastrectomia/métodos , Resultado do Tratamento
20.
Surg Endosc ; 37(12): 9318-9325, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37891370

RESUMO

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) has become an increasingly popular bariatric procedure. LSG still conveys some risks, including early staple line complications such as bleeding and leaks. It has been proposed that staple line complications can be reduced by staple line reinforcement (SLR). This study aimed to compare the short-term efficacy and safety of the SLR during LSG by oversewing versus no SLR in an Egyptian cohort over a period of 11 years. PATIENTS AND METHODS: This is a retrospective study that analyzed data from patients undergoing LSG by the same surgeon over a period of 11 years. The patients' early postoperative complications were compared according to performing SLR. RESULTS: The SLR group showed significantly longer surgery time (p = 0.021) and a lower rate of postoperative bleeding (p = 0.027). All leakage cases occurred in the non-SLR group (0.7% vs. 0.0%) without statistical significance (p = 0.212). The two mortality cases occurred in the non-SLR group. The LOS was comparable in the two groups (p = 0.289). CONCLUSION: This study confirms the short-term benefits of SLR by oversewing during LSG in terms of a lower incidence of 30-day morbidity, particularly bleeding, and lower rates of reoperation, with a clinically questionable longer operation time.


Assuntos
Laparoscopia , Obesidade Mórbida , Humanos , Estudos Retrospectivos , Laparoscopia/métodos , Egito , Grampeamento Cirúrgico/métodos , Obesidade Mórbida/cirurgia , Gastrectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Resultado do Tratamento
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