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1.
J Prosthodont ; 33(2): 141-148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36634341

RESUMO

PURPOSE: To assess the influence of print orientation on the surface roughness of implant-supported interim crowns manufactured by using digital light processing (DLP) 3D printing procedures. MATERIALS AND METHODS: An implant-supported maxillary right premolar full-contour crown was obtained. The interim restoration design was used to fabricate 30 specimens with 3 print orientations (0, 45, and 90 degrees) using an interim resin material (GC Temp PRINT) and a DLP printer (Asiga MAX UV) (n = 10). The specimens were manufactured, and each was cemented to an implant abutment with autopolymerizing composite resin cement (Multilink Hybrid Abutment). Surface roughness was assessed on the buccal surface of the premolar specimen by using an optical measurement system (InfiniteFocusG5 plus). The data were analyzed with a Shapiro-Wilk test, resulting in a normal distribution. One-way ANOVA and the Tukey HSD tests were selected (α = 0.05). RESULTS: Statistically significant discrepancies were found in the surface roughness mean values among the groups tested (p < 0.001). The lowest mean ± standard deviation surface roughness was found with the 90-degree group (1.2 ± 0.36 µm), followed by the 0-degree orientation (2.23 ± 0.18 µm) and the 45-degree group (3.18 ± 0.31 µm). CONCLUSIONS: Print orientation parameter significantly impacted the surface roughness of the implant-supported interim crowns manufactured by using the additive procedures tested.


Assuntos
Implantes Dentários , Desenho Assistido por Computador , Cimentos Dentários , Coroas , Cimentos de Ionômeros de Vidro , Teste de Materiais
2.
J Psychiatr Res ; 160: 171-176, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36804112

RESUMO

Deficits in functioning affect people with first-episode psychosis. Deficits in cognitive performance are common in such individuals and appear to be related to functioning. The present study examined the relationship between the domains of cognitive performance and personal and social functioning, as well as evaluating which cognitive domains are the most closely related to personal and social functioning and whether they explain variations once other clinical and sociodemographic aspects are accounted for. Ninety-four people with first-episode psychosis participated in the study; they were assessed with the MATRICS battery. Symptoms were evaluated with the Emsley factors of the positive and negative syndrome scale. Cannabis use, duration of untreated psychosis, suicide risk, perceived stress, antipsychotic doses, and premorbid intelligence quotient was accounted for. Processing speed, attention/vigilance, working memory, visual learning, reasoning and problem solving correlated to personal and social functioning. Processing speed emerged as the strongest predictor of social and personal functioning and underscores the importance of targeting this domain in treatment. Moreover, suicide risk and excited symptoms were also significant variables in functioning. Early intervention, focusing on improvement of processing speed, may be crucial to the improvement of functioning in first-episode psychosis. The relationship of this cognitive domain with functioning in first-episode psychosis should be studied further.


Assuntos
Antipsicóticos , Transtornos Cognitivos , Transtornos Psicóticos , Humanos , Velocidade de Processamento , Testes Neuropsicológicos , Transtornos Cognitivos/diagnóstico , Transtornos Psicóticos/tratamento farmacológico , Antipsicóticos/uso terapêutico , Cognição
4.
J Prosthet Dent ; 130(1): 48-58, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34809995

RESUMO

STATEMENT OF PROBLEM: Different techniques for retrieving cement-retained implant-supported prostheses have been described to minimize damage to the prostheses. Nevertheless, a classification of the described techniques remains ambiguous. PURPOSE: The purpose of this systematic review was to review and classify the described techniques for recording and locating the screw access hole in cement-retained implant-supported prostheses. MATERIAL AND METHODS: A bibliographic search was completed on MEDLINE/PubMed, Web of Science, Scopus, and Cochrane databases. A manual search was also conducted. The articles that described or evaluated techniques for recording and locating the screw access hole of cement-retained implant-supported prostheses were included. Two investigators independently assessed the quality assessment of the studies using the Revised Cochrane risk of bias tool for randomized trials. A third examiner was consulted to resolve the lack of consensus. RESULTS: A total of 30 articles were included. The different methods were classified according to whether the screw access hole location was registered before or after cementation. The precementation techniques were classified into 4 subgroups: identification marks, photographic records, digital files, and precementation screw access hole location guides. The postcementation techniques were subdivided into 2 subgroups: radiographic records and postcementation screw access hole location guides. CONCLUSIONS: Different techniques have been proposed to facilitate the location of the screw access hole in cement-retained implant-supported restorations. Although the evidence is scarce, studies seem to ascertain that some techniques, such as the use of drilling guides, orientation with cone beam computed tomography images, or holes made in the metal framework, can increase the retrievability of cement-retained implant-supported prostheses and decrease complications in the location of the screw access hole. The proposed classification summarizes precementation and postcementation techniques and provides a tool to decide the most suitable for each specific clinical situation.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante/métodos , Retenção em Prótese Dentária/métodos , Cimentos Dentários/uso terapêutico , Cimentação/métodos , Cimentos de Ionômeros de Vidro , Parafusos Ósseos
5.
Cancers (Basel) ; 14(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36291872

RESUMO

New techniques are being developed to improve the results of laparoscopic surgery for rectal cancer. This paper analyzes the learning curves for transanal total mesorectal excision (taTME) and robot-assisted surgery in our colorectal surgery department. We analyzed retrospectively data from patients undergoing curative and elective surgery for rectal cancer ≤12 cm from the anal verge. We excluded extended surgeries. We used cumulative sum (CUSUM) curve analysis to identify inflection points. Between 2015 and 2021, 588 patients underwent surgery for rectal cancer at our center: 67 taTME and 79 robot-assisted surgeries. To overcome the operative time learning curve, 14 cases were needed for taTME and 53 for robot-assisted surgery. The morbidity rate started to decrease after the 17th case in taTME and after the 49th case in robot-assisted surgery, but it is much less abrupt in robot-assisted group. During the initial learning phase, the rate of anastomotic leakage was higher in taTME (35.7% vs. 5.7%). Two Urological lesions occurred in taTME but not in robot-assisted surgery. The conversion rate was higher in robot-assisted surgery (1.5% vs. 10.1%). Incorporating new techniques is complex and entails a transition period. In our experience, taTME involved a higher rate of serious complications than robot-assisted surgery during initial learning period but required a shorter learning curve.

7.
PLoS One ; 17(2): e0264124, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35202394

RESUMO

BACKGROUND: The vast majority of COVID-19 cases both symptomatic and asymptomatic develop immunity after COVID-19 contagion. Whether lasting differences exist between infection and vaccination boosted immunity is yet to be known. The aim of this study was to determine how long total anti-SARS-CoV2 antibodies due to past infection persist in peripheral blood and whether sex, age or haematological features can influence their lasting. MATERIAL AND METHODS: A series of 2421 donations either of SARS-CoV-2 convalescent plasma or whole blood from 1107 repeat donors from January 2020 to March 2021 was analysed. An automated chemiluminescence immunoassay for total antibodies recognizing the nucleocapsid protein of SARS-CoV-2 in human serum and plasma was performed. Sex, age, blood group, blood cell counts and percentages and immunoglobulin concentrations were extracted from electronic recordings. Blood donation is allowed after a minimum of one-month post symptom's relapse. Donors were 69.7% males and their average age was 46. The 250 donors who had later donations after a positive one underwent further analysis. Both qualitative (positivity) and quantitative (rise or decline of optical density regarding consecutive donations) outcomes were evaluated. RESULTS AND DISCUSSION: In 97.6% of donors with follow-up, anti-SARS-CoV-2 protein N total antibodies remained positive at the end of a follow-up period of 12.4 weeks median time (1-46, SD = 9.65) after the first positive determination. The blood group was not related to antibody waning. Lower lymphocyte counts and higher neutrophils would help predict future waning or decay of antibodies. Most recovered donors maintain their total anti-SARS-CoV-2 N protein antibodies for at least 16 weeks (at least one month must have been awaited from infection resolution to blood donation). The 10 individuals that could be followed up longer than 40 weeks (approximately 44 weeks after symptom's relapse) were all still positive.


Assuntos
COVID-19/imunologia , COVID-19/terapia , SARS-CoV-2/imunologia , Imunidade Adaptativa/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Doadores de Sangue , COVID-19/sangue , Feminino , Humanos , Imunização Passiva , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Plasma , SARS-CoV-2/patogenicidade , Soroterapia para COVID-19
8.
J Prosthet Dent ; 127(2): 267-274, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33431173

RESUMO

STATEMENT OF PROBLEM: Interim dental prostheses can be fabricated by using subtractive or additive manufacturing technologies. However, the fracture resistance of implant-supported interim crowns fabricated by using vat-polymerization additive manufacturing methods remains unclear. PURPOSE: The purpose of this in vitro study was to evaluate the fracture resistance of anterior and posterior screw-retained implant-supported interim crowns fabricated by using subtractive and vat-polymerization direct light processing (DLP) additive manufacturing procedures. MATERIAL AND METHODS: An implant (Zinic Implant RP ∅4.0×10 mm) was placed in a 15×15-mm polymethylmethacrylate block. An implant abutment (ZiaCam, nonrotatory RP) was positioned on each implant. The virtual implant abutment standard tessellation language (STL) file provided by the manufacturer was imported into a software program (exocad v2.2 Valletta) to design 2 anatomic contour crowns, a maxillary right central incisor (anterior group) and a maxillary right premolar (posterior group). Each group was subdivided into 2 subgroups depending on the manufacturing method: milled (milled subgroup) and additive manufacturing (additive manufacturing subgroup). For the milled subgroup, an interim material (Vivodent CAD Multi) and a milling machine were used to fabricate all the specimens (N=40, n=10). For the additive manufacturing subgroup, a polymer interim material (SHERAprint-cb) and a DLP printer (SHERAprint 30) were used to manufacture all the specimens at a 50-µm layer thickness and 45-degree build orientation as per the manufacturer's instructions. Then, each specimen was cemented to an implant abutment by using composite resin cement (Multilink Hybrid Abutment HO) as per the manufacturer's instructions. A universal testing machine was used for fracture resistance analysis, and the failure mode was recorded. The Shapiro-Wilk test revealed that data were normally distributed. One-way ANOVA and Tukey multiple comparison were selected (α=.05). RESULTS: One-way ANOVA revealed significant differences among the groups (P<.05). The anterior milled subgroup obtained a significantly higher fracture resistance mean ±standard deviation value of 988.4 ±54.8 N compared with the anterior additive manufacturing subgroup of 636.5 ±277.1 N (P<.001), and the posterior milled subgroup obtained significantly higher mean ±standard deviation of 423.8 ±68 N than the additive manufacturing subgroup of 321.3 ±128.6 N (P=.048). All groups presented crown fracture without abutment fracture. CONCLUSIONS: Manufacturing procedures and tooth type influenced the fracture resistance of screw-retained implant-supported interim crowns. Milled specimens obtained higher fracture resistance compared with the DLP additive manufacturing groups. The anterior group was higher than the posterior group.


Assuntos
Implantes Dentários , Falha de Restauração Dentária , Desenho Assistido por Computador , Coroas , Cimentos Dentários , Porcelana Dentária , Prótese Dentária Fixada por Implante , Análise do Estresse Dentário , Teste de Materiais
9.
Langenbecks Arch Surg ; 406(2): 309-318, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33244719

RESUMO

PURPOSE: Laparoscopic surgery for rectal cancer is technically complex. This study aimed to identify risk factors for suboptimal laparoscopic surgery (involved margins, incomplete mesorectal excision, and/or conversion to open surgery) in patients with rectal cancer. METHODS: We included patients undergoing laparoscopic anterior resection for rectal cancer between June 2009 and June 2018. We defined the outcome variable suboptimal laparoscopic surgery as conversion to open surgery or inadequate histopathological specimens (margins < 1 mm or involved and/or poor-quality mesorectal excision). To identify independent predictors of suboptimal laparoscopic surgery, we analyzed 15 prospectively recorded demographic, clinical, and anthropometric variables obtained from our rectal cancer unit's database. Subanalyses examined the same variables with respect to conversion and to inadequate histopathological specimens. RESULTS: Of the 323 patients included, 91 (28.2%) had suboptimal laparoscopic surgery. In the multivariate analysis, the independent factors associated with all suboptimal laparoscopic surgery were tumor location ≤ 5 cm from the anal verge (OR = 2.95, 0.95% CI 1.32-6.60; p = 0.008) and the intertuberous distance (OR = 0.79, 0.95% CI 0.65-0.96; p = 0.019). In the subanalyses, the promontorium-retropubic axis was an independent predictor of conversion (OR 0.70, 0.95% CI 0.51-0.96; p = 0.026), and tumor location ≤ 5 cm from the anal verge (OR 3.71, 0.95% 1.51-9.15; p = 0.004) was an independent predictor of inadequate histopathological specimens. CONCLUSIONS: Predictive factors for suboptimal laparoscopic anterior resection for rectal cancer were tumor location and the intertuberous distance. These results could help surgeons decide whether to use other surgical approaches in complex cases. TRIAL REGISTRATION: The study was registered at Clinicaltrials.org (No. NCT03107650).


Assuntos
Laparoscopia , Neoplasias Retais , Conversão para Cirurgia Aberta , Humanos , Neoplasias Retais/cirurgia , Fatores de Risco , Resultado do Tratamento
10.
Int J Surg ; 83: 220-229, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33038521

RESUMO

BACKGROUND: Low anterior resection syndrome affects 60%-90% of patients with anastomoses after colorectal resection. Consensus regarding the best anastomosis is lacking. OBJECTIVE: To compare outcomes after end-to-end versus side-to-end anastomoses. DESIGN: Randomized clinical trial. SETTINGS: University hospital (April 2016-October 2017). PATIENTS: Patients aged ≥18 years with rectal or sigmoid adenocarcinoma. INTERVENTIONS: Patients were randomized to undergo mechanical end-to-end or side-to-end (n = 33) anastomosis after laparoscopic resection. MAIN OUTCOME MEASURES: Primary outcome was to assess intestinal function (COREFO and LARS questionnaires) 12 months after surgery or ileostomy closure. Secondary outcomes were postoperative complications and intestinal function and quality of life (SF-36® questionnaire) at different time points after surgery or ileostomy closure. RESULTS: No significant differences in intestinal function were observed between the two groups 12 months after surgery. Subanalysis of low-mid rectum tumors with end-to-end anastomosis yielded better function at 12 months. Postoperative complications did not differ between the two groups (p = 0.070), but reinterventions were more common in the side-to-end group (p = 0.040). Multivariate analysis found neoadjuvant treatment was independently associated with intestinal dysfunction at 12 months (ß = 0.41, p = 0.033, COREFO; ß = 0.41, p = 0.024, LARS). CONCLUSIONS: End-to-end anastomosis yielded low rates of severe complications and reintervention, as well as better intestinal function at 12 months in the subgroup with tumors in the low-mid rectum. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT02746224.


Assuntos
Adenocarcinoma/cirurgia , Anastomose Cirúrgica/métodos , Neoplasias Retais/cirurgia , Reto/cirurgia , Neoplasias do Colo Sigmoide/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Método Simples-Cego
11.
Chemistry ; 26(68): 15944-15952, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-32602582

RESUMO

In this paper, we highlight the synthesis of a variety of primary phosphine-boranes (RPH2 ⋅BH3 ) from the corresponding dichlorophosphines, simply by using Li[BH4 ] as reductant and provider of the BH3 protecting group. The method offers facile access not only to alkyl- and arylphosphine-boranes, but also to aminophosphine-boranes (R2 NPH2 ⋅BH3 ) that are convenient building blocks but without the protecting BH3 moiety thermally labile and notoriously difficult to handle. The borane-protected primary phosphines can be doubly deprotonated using n-butyllithium to provide soluble phosphanediides Li2 [RP⋅BH3 ] of which the phenyl-derivative Li2 [PhP⋅BH3 ] was structurally characterized in the solid state.

14.
Eur J Pharm Sci ; 105: 159-168, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28502672

RESUMO

The efficacy of microtubule targeting agents in cancer treatment has been compromised by the development of drug resistance that may involve both, P-glycoprotein overexpression and the changes in ß-tubulin isoforms' expression. The anti-Topoisomerase II activity of methyl 4-((E)-2-(methoxycarbonyl)vinyloxy)oct-2-ynoate (DTA0100) was recently reported. Herein, we further evaluated this propargylic enol ether derivative and found that it exerts inhibitory effect on tubulin polymerization by binding to colchicine binding site. DTA0100 mitotic arrest properties were investigated in two multi-drug resistant cancer cell lines with P-glycoprotein overexpression (colorectal carcinoma and glioblastoma). The sensitivity of multi-drug resistant cancer cell lines to DTA0100 was not significantly changed in contrast to microtubule targeting agents such as paclitaxel, vinblastine and colchicine. DTA0100 clearly induced microtubule depolymerization, leading to disturbance of cell cycle kinetics and subsequent apoptosis. The fine-tuning in ß-tubulin isoforms expression observed in multi-drug resistant cancer cells may influence the efficacy of DTA0100. Importantly, DTA0100 blocked the P-glycoprotein function in both multi-drug resistant cancer cell lines without inducing the increase in P-glycoprotein expression. Therefore, DTA0100 acting as dual inhibitor of Topoisomerase II and microtubule formation could be considered as multi-potent anticancer agent. Besides, it is able to overcome the problem of drug resistance that emerges in the therapeutic approaches with either Topoisomerase II or microtubule targeting agents.


Assuntos
Acrilatos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Caprilatos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Paclitaxel/farmacologia , Inibidores da Topoisomerase II/farmacologia , Moduladores de Tubulina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
15.
Int J Surg Case Rep ; 8C: 25-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25616071

RESUMO

INTRODUCTION: Primary aorto-enteric fistula (AEF) is an uncommon life-threating condition. Only 4% of them involve the jejunum or ileum and its mortality ranges from 33 to 85%. PRESENTATION OF CASE: A 54-year-old female was admitted to the Emergency Department with syncope and hematemesis. The esophagogastroduodenoscopy found a pulsatile vessel in the second portion of the duodenum. A computed tomography scan showed an AEF with an infrarenal aortic aneurysm and iliac artery thrombosis. During surgery, an infrarenal aortic aneurysm complicated with an aorto-jejunal fistula was found. An axilo-bifemoral bypass, open repair of the aneurysm and segmental small bowel resection with primary suture of the jejunal defect were performed. DISCUSSION: Depending on previous aortic grafting, AEF can be classified as primary or secondary. Primary AEF is usually caused by an untreated abdominal aortic aneurysm, commonly presenting an infectious etiology. The main clinical sign is a "herald" hemorrhage. The EGD is considered as the first step in diagnosing AEF. The treatment of choice for AEF is emergent surgery. Use of broad-spectrum antibiotics is mandatory in the postoperative period to avoid fistula recurrence. CONCLUSION: AEF is a rare entity with a high mortality. High clinical suspicion is essential to make a correct diagnosis, which is crucial for the prognosis of these patients, such is the case of our patient. If hemodynamic stability is achieved, it allows to employ surgical strategies in which extra-abdominal bypass is performed before fistula is treated.

16.
Chem Commun (Camb) ; 50(28): 3685-8, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24573686

RESUMO

The enantioselective formal synthesis of (-)-isolaurepinnacin and (+)-rogioloxepane A has been achieved. The key steps are an intermolecular Nicholas reaction with a ß-hydroxy-γ-lactone as the nucleophile, to form branched linear ethers, and an olefin ring-closing metathesis to obtain the oxepene core.


Assuntos
Lactonas/química , Oxepinas/síntese química , Oxepinas/química , Estereoisomerismo
17.
Angew Chem Int Ed Engl ; 53(33): 8751-5, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-24554623

RESUMO

An enantioselective hydrogenation of disubstituted furans has been developed by using a chiral ruthenium catalyst with N-heterocyclic carbene ligands. This reaction converts furans into valuable enantioenriched disubstituted tetrahydrofurans.


Assuntos
Furanos/química , Catálise , Compostos Heterocíclicos/química , Hidrogenação , Metano/análogos & derivados , Metano/química , Pressão , Rutênio/química , Solventes/química , Estereoisomerismo , Temperatura
19.
Org Lett ; 15(7): 1776-9, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-23521074

RESUMO

The homogeneous catalyzed dehydrogenation of methanol in a synthetically valuable cross-coupling reaction was achieved. By the use of a simple ruthenium-N-heterocyclic carbene complex, MeOH and primary or secondary amines can be converted into formamides.

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