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1.
Macromol Rapid Commun ; 44(10): e2300039, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37005746

RESUMO

Introducing the reverse micelle formation during polymerization, and thus avoiding the catalyst support, aggregated single crystals of ultra-high molecular weight isotactic polypropylene having spherical morphology are obtained. The ease in flowability of the spherical nascent morphology, having a low-entangled state in the non-crystalline region of the single crystals in the semi-crystalline polymer, allows the sintering of the nascent polymer in the solid state without melting. Thus maintains a low-entangled state, and facilitates the translation of macroscopic forces to macromolecular length scale, without melting, leading to the formation of uniaxially drawn objects having unprecedented properties that can be used in the development of one component, high-performance, easy-to-recycle composites. Thus having the potential of replacing difficult-to-recycle hybrid composites.


Assuntos
Polímeros , Polipropilenos , Polipropilenos/química , Peso Molecular , Polímeros/química , Substâncias Macromoleculares , Polimerização
2.
Endocr Pract ; 28(2): 135-141, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34481972

RESUMO

OBJECTIVE: The present study aimed to evaluate gestational diabetes mellitus (GDM) incidence in pregnant women following the Mediterranean diet (MedDiet) with the addition of extra virgin olive oil (EVOO) and pistachios. METHODS: A total of 560 pregnant patients were enrolled in the present study. The MedDiet was introduced in both the interventional group (IG) and the control group. The women in the IG received 40 mL of EVOO every day along with 25 to 30 g of roasted pistachios. The incidence of GDM was recorded along with specific maternal and neonatal outcomes. RESULTS: The nutritional scores and MedDiet adherence screener scores were not statistically different between the groups at baseline, but the difference was statistically significant and higher in the IG at 24 to 28 weeks (P = .001) and at 36 to 38 weeks (P = .001). GDM was diagnosed in 51 (20.4%) women in the control group and 34 (13.6%) women in the IG. The MedDiet significantly reduced GDM incidence (P = .02) after adjusting for confounding factors. CONCLUSION: The present study shows that dietary intervention in pregnant women, including a MedDiet and increased consumption of EVOO and pistachios, decreases the incidence of GDM.


Assuntos
Diabetes Gestacional , Dieta Mediterrânea , Pistacia , Diabetes Gestacional/epidemiologia , Diabetes Gestacional/prevenção & controle , Feminino , Humanos , Incidência , Recém-Nascido , Azeite de Oliva , Gravidez
3.
Bull World Health Organ ; 97(12): 799-809, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31819288

RESUMO

OBJECTIVE: To determine the effect of different hypertension management guidelines and of basing diagnosis on a single reading of blood pressure on the hypertension prevalence in the Indian population. METHODS: We performed a secondary analysis of data acquired as part of the Fourth national family health survey, 2015 to 2016, over all districts in India. We calculated the proportion of the population within three different age groups (18 to 34, 35 to 49 and 18 to 49 years of age) with raised blood pressure according to six different guidelines, and how prevalence changed if diagnoses were based on a single blood pressure measurement. FINDINGS: We observed that the Government of India and the American College of Cardiology/American Heart Association guidelines consistently yielded the lowest and highest prevalence of raised blood pressure; in the combined age group, we calculated the proportion of the population categorized as having raised blood pressure as 7.5% (95% confidence interval (CI): 7.4 to 7.7) and 40.1% (95% CI: 39.7 to 40.7), respectively. When basing diagnosis on a single reading of blood pressure only, a total of 56 million individuals would be erroneously categorized as hypertensive following the Government of India guidelines. We also showed that prevalence of hypertension in India varies with guidelines adhered to; in the combined age group, the national hypertension prevalence was three times higher when following the American College of Cardiology/American Heart Association compared with the Government of India guidelines. CONCLUSION: To optimize current clinical practice, health-care providers need to follow universally agreed, evidence-based methods of diagnosing hypertension.


Assuntos
Hipertensão/epidemiologia , Guias de Prática Clínica como Assunto/normas , Adolescente , Adulto , Fatores Etários , Pressão Sanguínea , Feminino , Inquéritos Epidemiológicos , Humanos , Índia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
4.
Clin Oral Investig ; 23(5): 2071-2075, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30238418

RESUMO

OBJECTIVE: To assess the correlation of skip metastases associated with increase in tumor thickness and size of the tumor. MATERIAL AND METHODS: A retrospective analysis was carried out from August 2009 to August 2015. In this study, a total number of 33 carcinoma tongue patients having T1, T2, and T3 sizes with N0 and N+ clinical necks who were treated by supraomohyoid neck dissection, extended supraomohyoid neck dissection, and modified radical neck dissection were analyzed. The data was assessed using Shapiro-Wilk W test, Nagelkerke R2 regression model, mean, and standard deviation. RESULTS: Metastasis to lymph nodes was present in 75% of patients. Level I and level II were the commonest sites to be involved, i.e., 20 patients. Three patients had skip metastasis out of which two patients had metastasis at level III (6%), and one patient had skip metastasis at level IV (3%). CONCLUSION: The incidence of skip metastasis increases with tumor thickness and tumor size in tongue carcinoma patients. CLINICAL RELEVANCE: The article reveals the positive relationship between tumor thickness, tumor size, and skip metastasis. The analysis shows tumor thickness as a higher predictor for skip metastasis with odds ratio of 5.5 compared to the tumor size having odd ratio 2.


Assuntos
Carcinoma/patologia , Metástase Linfática/patologia , Neoplasias da Língua/patologia , Adulto , Idoso , Carcinoma/cirurgia , Feminino , Humanos , Linfonodos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias da Língua/cirurgia
5.
J Oral Maxillofac Surg ; 76(3): 647-655, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28863886

RESUMO

PURPOSE: To estimate the clinical and functional results of patients who underwent distinctive types of neck dissection, with particular emphasis on shoulder function, rate of recurrence, and quality of life in patients with N0 neck. MATERIALS AND METHODS: A randomized clinical trial was conducted from August 2014 to March 2017 in which 20 adult patients with T1 to T3 lesions of the oral cavity and N0 neck were included. Patients were randomly allocated to group I (n = 10; selective neck dissection) or group II (n = 10; superselective neck dissection). All patients were evaluated objectively for degree of arm abduction and subjectively for quality of life using a questionnaire completed pre- and postoperatively at 6 months. Also, locoregional recurrence was investigated for 2.5 years. Data were scrutinized by applying mean and standard deviation, unpaired t test, Mann-Whitney U test, and Kaplan-Meier test. RESULTS: Mean values of the Arm Abduction Test and quality-of-life scores were statistically significant (P < .05) for group II compared with group I at all intervals. Data analyzed for locoregional recurrence showed a statistically significant difference between groups (P < .05), with group II having the better outcome. CONCLUSION: The results showed less shoulder morbidity and improved quality of life for superselective neck dissection (group II) compared with selective neck dissection (group I). Furthermore, group II was better for locoregional recurrence, which determines the oncologic safety of the procedure.


Assuntos
Neoplasias Bucais/cirurgia , Esvaziamento Cervical/métodos , Ombro/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical/efeitos adversos , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/prevenção & controle , Qualidade de Vida , Resultado do Tratamento
6.
Macromol Rapid Commun ; 36(3): 327-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25504497

RESUMO

Recently, it has been shown that by using a single-site catalytic system having titanium as a metallic center, it is possible to tailor the entanglement density in the amorphous region of a semi-crystalline ultra-high molecular weight polyethylene (UHMWPE). This route provides the possibility to make high-modulus, high-strength uniaxially and biaxially drawn tapes and films, without using any solvent during processing. In this publication, it is shown that a single-site catalyst having chromium as metallic center, proposed by Enders and co-workers, can also be tuned to provide control on the entanglement density during synthesis of the UHMWPE. However, to achieve the goal some modifications during the synthesis are required. The synthesized polymers can be processed in the solid state below the equilibrium melting temperature, resulting in uniaxially drawn tapes having tensile strength and modulus greater than 3.5 N/tex and 200 N/tex, respectively. Rheological studies have been performed to follow the increase in entanglement density in melt state with time.


Assuntos
Cromo/química , Compostos Organometálicos/química , Polietilenos/química , Polietilenos/síntese química , Materiais Biocompatíveis/química , Catálise
7.
Int J Surg ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39166941

RESUMO

BACKGROUND: Surgical site infection (SSI) is the prevailing complication that occurs after surgery and significantly escalates healthcare expenses. Published meta-analyses and international standards vary in their recommendations for the most effective preoperative skin antiseptic solution and concentration. OBJECTIVE: The aim of this systematic review and meta-analysis is to assess the effectiveness of Chlorhexidine-alcohol compared to Aqueous/alcoholic iodine solutions in preventing post-operative surgical site infections. METHODS: A systematic search was conducted using four electronic databases (PubMed, EMBASE, Scopus, and Cochrane Library) to select publications published in peer-reviewed journals. The risk ratio (RR) was calculated, along with their 95% confidence intervals. We assessed heterogeneity using Cochrane Q and I2 statistics and the appropriate P-value. The analysis used RevMan 5.4. RESULTS: The current meta-analysis includes 14 Randomized controlled trials (RCTs) comparing either 2-2.5% chlorhexidine alcohol with aqueous/alcoholic iodine. It was demonstrated that the CAG-using group had an overall lower incidence of post-operative surgical site infections compared to the iodine-using group (RR=0.30, 95% CI=0.20 to 0.46, I2=95%, P<0.00001). It exhibits comparable efficacy across various surgical procedures, as evidenced by its RR of 0.25 [95% CI 0.15 to 0.41], I2=51%, and P<0.0001 for general surgery, RR=0.47 [95% CI 0.32 to 0.67], I2=82%, P=0.0002 for caesarean section and RR of 0.47 [95% CI 0.34 to 0.65], I2=76% and P<0.00001 for additional surgical procedures, including neurosurgery, orthopedic surgery etc. CONCLUSION: This meta-analysis suggests using either 2·0-2·5% Chlorhexidine in alcohol instead of aqueous, alcoholic iodine to prevent SSIs in adult patients undergoing surgery. Chlorhexidine in alcohol worked effectively for general surgery, cesarean sections, and other surgeries. Thus, preoperative skin cleansing with Chlorhexidine alcohol minimizes postoperative SSIs and bacterial colonization in diverse procedures.

8.
Heliyon ; 9(9): e19527, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809875

RESUMO

Background: Gestational hypertension and pre-eclampsia often increase maternal and neonatal mortality. The illness usually appears after the 20th week of pregnancy due to malnutrition or obesity. Untreated, it can lead to neonatal and maternal mortality. Low-dose Aspirin can prevent preeclampsia if started between 11 and 28 weeks. Several studies support this technique, although others have shown limited effectiveness and negative side effects. Objective: This study aims to assess the effectiveness of aspirin treatment for the prevention of preeclampsia, taking into account any possible adverse reactions. Methods: This observational research comprised 600 singleton pregnant women at high risk of pregnancy-induced hypertension. The aspirin group had 301 individuals and the placebo group 299. From 11 to 36 weeks of pregnancy, they received 150 mg of aspirin and 150 mg of placebo. Gestational hypertension was assessed at 25 weeks, 36 weeks, and 37 weeks. If any, aspirin and placebo-related adverse pregnancy and neonatal outcomes were reported. Results: With aspirin therapy, 4 females and 14 females with placebo developed gestational hypertension before 25 weeks of pregnancy with an odds ratio of 0.283 (0.092-0.87); before 36 weeks, 5 females and 15 females with placebo developed GHD with an odds ratio of 0.331 (0.118-0.922); and after 37 weeks, 17 females and 35 females with placebo developed GHD. Preeclampsia occurred in 5 females in the aspirin group and 17 in the placebo group at <25 weeks (odds ratio 0.292 (0.106-0.802), 7 females in the aspirin arm and 25 females in the placebo arm at <36 weeks (odds ratio 0.278 (0.118-0.652), and 21 females in the aspirin arm and 39 females in the placebo arm at >37 weeks (odds ratio 0.5349 (0.307-0.930). Conclusion: In pregnant women at high risk of prenatal hypertension and preeclampsia, aspirin therapy is very effective with minimal side effects.

9.
Wideochir Inne Tech Maloinwazyjne ; 18(1): 31-41, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37064561

RESUMO

Introduction: The main components of enteral immunonutrition (EIN) are ω-3 fatty acids, glutamine, arginine, and nucleotide, which primarily raises the immunity of the host and helps to reduce postoperative infections and non-infectious difficulties. Although the potential benefits of EIN are widely reported, some researchers did not find it to be of much help, and hence valid conclusions about its role are still unclear. Aim: To evaluate the role of enteral immunonutrition on patients undergoing surgery for gastric cancer (GC). Material and methods: Appropriate articles were searched from the PubMed, Medline, and Central databases using the appropriate keywords as per the PRISMA guidelines. Randomized controlled trials, and retrospective, prospective, and open-label studies were included as per the predefined PICOS criteria. Demographic summary and event data for the effect of EIN on patients undergoing surgery for GC were extracted from the included studies. Results: Twelve randomized controlled clinical trials with a total of 10,422 gastric cancer patients were included. We found the odds ratio value of 0.23 (95% CI: 0.09-0.59). The results are heterogeneous with a τ2 value of 2.77, a χ2 value of 1707.96, a df value of 11, an I2 value of 99%, a z value of 3.04, and a p-value of less than 0.05. The risk ratio is 0.47 (95% CI: 0.29-0.77) with heterogeneity of τ2 value of 0.73, χ2 value of 1428.34, df value of 11, I2 value of 99%, z value of 2.99, and p-value < 0.05. Conclusions: The present meta-analysis strongly commends the use of EIN to boost the immunity of gastric cancer (GC) patients undergoing gastrectomy.

10.
J Orthop Surg Res ; 18(1): 572, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543643

RESUMO

BACKGROUND: Laminar airflow (LAF) technologies minimize infectious microorganisms to enhance air quality and surgical site infections (SSIs). LAF lowers SSIs in some clinical studies but not others. This study analyzes laminar airflow ventilation's capacity to reduce orthopaedic surgery-related SSIs. METHODS: The PRISMA-compliant keywords were utilized to conduct a search for pertinent articles in various databases including PubMed, MEDLINE, CENTRAL, Web of Sciences, and the Cochrane databases. Observational studies, including retrospective, prospective, and cohort designs, satisfy the PICOS criteria for research methodology. The assessment of quality was conducted utilizing the Robvis software, while the meta-analysis was performed using the RevMan application. The study's results were assessed based on effect sizes of odds ratio (OR) and risk ratio (RR). RESULTS: From 2000 to 2022, 10 randomized controlled clinical trials with 10,06,587 orthopaedic surgery patients met the inclusion criteria. The primary outcomes were: (1) Risk of SSI, (2) Bacterial count in sampled air and (3) Reduction in SSIs. The overall pooled OR of all included studies was 1.70 (95% CI 1.10-2.64), and the overall pooled RR was 1.27 (95% CI 1.02-1.59) with p < 0.05. LAF is ineffective at preventing SSIs in orthopaedic procedures due to its high-risk ratio and odds ratio. CONCLUSIONS: The present meta-analysis has determined that the implementation of LAF systems does not result in a significant reduction in the incidence of surgical site infections (SSIs), bacterial count in the air, or SSIs occurrence in orthopaedic operating rooms. Consequently, the installation of said equipment in operating rooms has been found to be both expensive and inefficient.


Assuntos
Ortopedia , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia , Salas Cirúrgicas , Estudos Prospectivos , Estudos Retrospectivos
11.
Med Ultrason ; 25(1): 66-71, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35437526

RESUMO

AIM: To assess chest ultrasound (US) diagnostic accuracy in pneumothorax diagnosing. MATERIAL AND METHODS: Prospec-tive studies related to the US pneumothorax diagnostic accuracy in trauma patients were extensively searched from 2000 up to November 2020. The studies features and findings were gathered using a standardised form and the methodological quality of the investigations was evaluated using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). RESULTS: Twelve articles were finally chosen for quantitative analysis. The overall sensitivity of US scan in pneumothorax diagnosis was 89% (95%CI 86-91%). Specificity was 96% (95%CI 95-97%). The diagnostic odds ratio was 193.94 (59.009-637.40) at 95%CI, thus demonstrating high chest US accuracy in pneumothorax diagnosis. CONCLUSION: Despite the limitations of the included studies, this systematic review and meta-analysis concluded that chest US is a reliable method for diagnosing pneu-mothorax in traumatized patients.


Assuntos
Pneumotórax , Traumatismos Torácicos , Ferimentos não Penetrantes , Humanos , Pneumotórax/diagnóstico por imagem , Sensibilidade e Especificidade , Traumatismos Torácicos/complicações , Traumatismos Torácicos/diagnóstico por imagem , Ultrassonografia/métodos
12.
Exp Ther Med ; 26(1): 347, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37383380

RESUMO

Oral mucositis (OM) is a commonly observed and debilitating side effect of chemotherapy and radiation therapy in patients with cancer, especially head and neck cancer. Although there is no proven therapy for the prevention and treatment of OM, zinc supplementation effectively decreases the incidence of OM. This paper provides a current and comprehensive meta-analysis of the efficacy of zinc compared with placebo/control in OM. A systematic literature review was conducted using MEDLINE and Central databases for randomized control trials (RCTs) comparing zinc supplementation (oral or rinse) with placebo/control in patients with various types of cancer undergoing chemotherapy, radiation therapy or combined chemo-radiation. The outcome was OM incidence, independent of the severity. A random-effects model was used to calculate the pooled risk ratio and subgroup analyses were performed. A total of 12 RCTs were included, containing information from 783 patients. A decrease in OM incidence was observed overall when all cancer therapies were considered. However, subgroup analyses showed that zinc did not significantly decrease the incidence of OM when studies were stratified by cancer therapy or scale/criteria used to assess OM. The results of the meta-analysis support the use of zinc supplementation in decreasing OM incidence in patients with cancer receiving chemotherapy or radiation therapy. However, the high heterogeneity between studies and the small number of studies are limitations of the meta-analysis.

13.
Adv Clin Exp Med ; 32(12): 1357-1368, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37166014

RESUMO

BACKGROUND: Health literacy and self-efficacy related to COVID-19 pandemic management are closely linked. Therefore, synthesis of relevant evidence regarding the positive aspects of health literacy and health-promoting protective measures among individuals during COVID-19 pandemic is necessary. OBJECTIVES: To determine the influence of e-health literacy and health-promoting coronavirus disease 2019 (COVID-19) protective behaviors on the spread of infection during the COVID-19 pandemic. MATERIAL AND METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, PubMed, MEDLINE, PsycINFO, EMBASE, and Cochrane Library databases, as well as PROSPERO and ClinicalTrials.gov registry platforms were searched for eligible literature published from January 2020 to July 2022. Studies were included based on predefined Population, Intervention, Comparison, Outcomes and Study design (PICOS) criteria, and a summary of each study was prepared. To estimate the effect size, the standardized mean difference (SMD) of the evaluated parameters, e-health literacy and health-promoting COVID-19 protective behaviors was extracted. Using RevMan and MedCalc software, a meta-analysis was performed. RESULTS: Twelve eligible studies involving a total of 9854 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals were included in the meta-analysis. The pooled SMD for e-health literacy was 40.39 (95% confidence interval (95% CI): 28.14-52.63), with the following heterogeneity values: Tau2 of 396.80, ÷2 of 669.48, degrees of freedom (df) of 11, I2 of 98%, Z value of 6.47, and p < 0.001. Similarly, the pooled SM for COVID-19 protective behaviors was 15.90 (95% CI: 10.96-20.84) with Tau2 of 55.25, ÷2 of 252.92, df of 11, I2 of 98%, Z of 6.31, and p < 0.001. CONCLUSION: This study confirmed that e-health literacy and health-promoting COVID-19 protective behaviors have a strong positive impact on preventing the spread of COVID-19 infection and on its effective management. We recommend that interventions and applicable policies for promoting such e-literacy programs and preventative measures be given a high level of consideration.


Assuntos
COVID-19 , Letramento em Saúde , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2
14.
Wideochir Inne Tech Maloinwazyjne ; 17(4): 611-623, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36818516

RESUMO

Introduction: Due to the complicated surgical procedure of knee arthroplasty and low effectivity of hyaluronic acid (HA) in the treatment of knee osteoarthritis, various studies highly recommend the use of platelet-rich plasma (PRP). However, some studies also reported lower efficacy and limited use of PRP. Aim: To analyze systematically the different randomized controlled trials (RCTs) comparing the effectiveness of HA vs. PRP for the treatment of knee osteoarthritis. Material and methods: A systematic literature review was conducted using Medline and Central databases for RCTs about the comparison of HA vs. PRP for the treatment of knee osteoarthritis. Studies were included as per the PICOS criteria and relevant event data were extracted. Risk of bias was analyzed and a random-effects model was used to calculate the pooled odds ratio and risk ratio using RevMan software. Results: A total of 14 studies were included in the meta-analysis from year 2000 to 2021 including 613 patients. The current meta-analysis has a low risk of publication bias and we obtained the pooled odds ratio (OR) of 2.55 (95% CI: 1.35-4.84) with a τ 2 value of 1.01, χ 2 value of 52.79, I2 value of 77%, Z value of 2.87 and p-value < 0.00001. The pooled risk ratio was 1.34 (95% CI: 1.09-1.65) with a τ 2 value of 0.09, χ 2 value of 73.48, I2 value of 84%, Z value of 2.80 and p-value < 0.00001. Conclusions: The current meta-analysis highly recommends the use of PRP for the treatment of knee osteoarthritis.

15.
J Oral Biol Craniofac Res ; 12(5): 694-701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092459

RESUMO

Objective: To determine the impact of the buccal envelope flap and pedicle design on the post-operative outcome and quality of life following lower third molar surgery (QoL). Materials and methods: A randomized case-control clinical study was carried out from September 2017 to September 2019. In this study, a total number of 50 patients with mandibular third molar impaction underwent surgical removal of the same using buccal envelope flap (group A) and pedicle flap (group B). The patients were assessed postoperatively for pain, swelling, trismus, wound dehiscence, dry socket, and quality of life for one month. Results: In terms of pain, swelling, and trismus, there was no statistical difference between the two groups (p > 0.05). However, there was a statistically significant difference found in group B (pedicle flap) in terms of wound dehiscence, dry socket, and quality of life (p < 0.05). Conclusion: The pedicle flap demonstrates fewer incidences of wound dehiscence, dry socket, and a better quality of life when compared to the envelope flap.

16.
Nanomaterials (Basel) ; 12(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36364602

RESUMO

A network of nanofibers is formed in situ through solid-state deformation of disentangled ultra-high molecular weight polyethylene (dis-UHMWPE) during compounding with a polyolefin elastomer below the melting temperature of dis-UHMWPE crystals. Dis-UHMWPE was prepared in the form of powder particles larger than 50 µm by polymerization at low temperatures, which favored the crystallization and prevention of macromolecules from entangling. Shearing the blend for different durations and at different temperatures affects the extent to which the grains of dis-UHMWPE powder deform into nanofibers. Disentangled powder particles could deform into a network of nanofibers with diameters between 110 and 340 nm. The nanocomposite can be further sheared for a longer time to decrease the diameter of dis-UHMWPE nanofibers below 40 nm, being still composed of ≈70 wt.% of crystalline and ≈30 wt.% of amorphous components. Subsequently, these thinner fibers begin to melt and fragment because they are thinner and also because the amorphous defects locally decrease the nanofibers' melting temperature, which results in their fragmentation and partial loss of nanofibers. These phenomena limit the thickness of dis-UHMWPE nanofibers, and this explains why prolonged or more intense shearing does not lead to thinner nanofibers of dis-UHMWPE when compounded in a polymeric matrix.

17.
Front Surg ; 9: 855409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402490

RESUMO

Background: Increased risk of surgical site infections (SSIs) caused by hyperglycemia makes it necessary to follow perioperative glucose lowering strategies to reduce postoperative complications. A meta-analysis was conducted to understand the efficacy of intensive vs. conventional blood glucose lowering regimens on the incidence of SSIs and hypoglycemia from various randomized controlled studies (RCTs). Materials and Methods: A systematic literature review was conducted using MEDLINE and Central databases for RCTs that involved intensive (lower blood glucose target levels) vs. conventional (higher blood glucose target levels) strategies in patients undergoing various types of surgeries. The primary outcomes were SSIs or postoperative wound infections. Hypoglycemia and mortality outcomes were also studied. A random-effects model was used to calculate the pooled risk ratio (RR), and subgroup analyses were performed. Results: A total of 29 RCTs were included in the meta-analysis with the information from 14,126 patients. A reduction in overall incidence of SSIs was found (RR 0.63, 0.50-0.80, p = 0.0002, I 2= 56%). Subgroup analyses showed that intensive insulin regimens decreased the risk of SSIs in patients with diabetes, in cardiac and abdominal surgical procedures, and during the intraoperative and postoperative phases of surgery. However, the risk of hypoglycemia and mortality was increased in the intensive group compared to the conventional group. Conclusion: The results of the meta-analysis provide support for the use of intensive insulin regimens during the perioperative phase for decreasing the incidence of SSIs in certain patient populations and surgical categories.

18.
Wideochir Inne Tech Maloinwazyjne ; 17(2): 261-278, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35707338

RESUMO

Introduction: Surgical site infections (SSIs) occur after an operative procedure and can range from superficial to deep wound infections. The World Health Organization (WHO) and the Centers for Disease Control (CDC) have proposed guidelines recommending measures to prevent SSIs. Intraoperative measures are largely focused on decontamination of the skin and intraoperative wound irrigation using soap and antiseptics and are simple, efficient, and cost-effective measures to reduce SSIs. Povidone-iodine (PVI) is a topical antiseptic widely used for the reduction of SSIs. Aim: A meta-analysis was conducted to determine the efficacy of preoperative or intraoperative use of PVI from randomized controlled trials (RCTs). Material and methods: A systematic literature review was conducted using MEDLINE and Central databases for RCTs that involved PVI application versus saline or no treatment control groups across various surgical categories. The primary outcome was SSI or post-operative wound infections. A random-effects model was used to calculate the pooled risk ratio and subgroup analyses were performed. Results: A total of 59 RCTs were included in the meta-analysis with information from 20,497 patients. A reduction in overall SSI incidence was found (RR = 0.70, 0.60-0.80, p = 0.0002, I2 = 44%). Subgroup analyses showed that the comparator treatment and type of procedure did not modify the effect of PVI on SSI incidence. However, inconsistent results on SSI incidence were obtained when the data were stratified by PVI application method and surgery category. Conclusions: The results of the meta-analysis provide support for the preoperative or intraoperative use of PVI in decreasing the incidence of SSI.

19.
Front Surg ; 9: 912295, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784917

RESUMO

[This corrects the article DOI: 10.3389/fsurg.2022.855409.].

20.
J Oral Biol Craniofac Res ; 12(1): 22-26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34745860

RESUMO

BACKGROUND/PURPOSE: This research aimed to compare the effects of systemically prescribed Lycopene as a monotherapy and as an alternative to scaling and root planing in patients with chronic gingivitis. MATERIALS AND METHODS: The participants were randomly assigned to one of two treatment groups: the experimental group (n = 50), which received 10 mg of Lycopene a day for two weeks, or the control group (n = 50) received a placebo for two weeks. For each category, quadrant distribution was randomized, with two quadrants receiving oral prophylaxis (OP) and two quadrants receiving no care (non-OP). At baseline, 1st, and 2nd weeks, the sulcus bleeding index, plaque index, gingival index, and salivary uric acid level were measured. RESULTS: All clinical criteria, including SBI, PI, GI, and salivary uric acid levels, showed a statistically significant decline in all patient types. Both clinical parameters were significantly reduced (p < 0.001) in the OP-lycopene group relative to the non-OP-placebo group and non-OP lycopene group (p < 0.05). The PI value in the OP-lycopene group was statistically significantly lower (p < 0.001) than in the non-OP-placebo group; there was no statistically significant difference in the other groups. Salivary uric acid levels in the OP- and non-OP- lycopene groups were significantly lower (p < 0.001) than in the non-OP-placebo population. CONCLUSION: Based on the findings of this study, Lycopene seems to have a bright future as a treatment option for plaque-induced generalized chronic marginal gingivitis. More research with a broad sample size and multicentre trials is required. CLINICAL RELEVANCE: The article reveals the positive relationship between Lycopene and gingivitis. The analysis shows that a combination of systemically administered Lycopene with oral prophylaxis can be a valuable tool in treating chronic gingivitis and controlling respiratory oxidative stress.

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