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1.
Sci Robot ; 7(62): eabj2908, 2022 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-35080901

RESUMEN

Autonomous robotic surgery has the potential to provide efficacy, safety, and consistency independent of individual surgeon's skill and experience. Autonomous anastomosis is a challenging soft-tissue surgery task because it requires intricate imaging, tissue tracking, and surgical planning techniques, as well as a precise execution via highly adaptable control strategies often in unstructured and deformable environments. In the laparoscopic setting, such surgeries are even more challenging because of the need for high maneuverability and repeatability under motion and vision constraints. Here we describe an enhanced autonomous strategy for laparoscopic soft tissue surgery and demonstrate robotic laparoscopic small bowel anastomosis in phantom and in vivo intestinal tissues. This enhanced autonomous strategy allows the operator to select among autonomously generated surgical plans and the robot executes a wide range of tasks independently. We then use our enhanced autonomous strategy to perform in vivo autonomous robotic laparoscopic surgery for intestinal anastomosis on porcine models over a 1-week survival period. We compared the anastomosis quality criteria-including needle placement corrections, suture spacing, suture bite size, completion time, lumen patency, and leak pressure-of the developed autonomous system, manual laparoscopic surgery, and robot-assisted surgery (RAS). Data from a phantom model indicate that our system outperforms expert surgeons' manual technique and RAS technique in terms of consistency and accuracy. This was also replicated in the in vivo model. These results demonstrate that surgical robots exhibiting high levels of autonomy have the potential to improve consistency, patient outcomes, and access to a standard surgical technique.


Asunto(s)
Anastomosis Quirúrgica/métodos , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Algoritmos , Anastomosis Quirúrgica/instrumentación , Anastomosis Quirúrgica/estadística & datos numéricos , Animales , Procedimientos Quirúrgicos del Sistema Digestivo/instrumentación , Procedimientos Quirúrgicos del Sistema Digestivo/estadística & datos numéricos , Humanos , Intestino Delgado/cirugía , Laparoscopía/instrumentación , Laparoscopía/métodos , Laparoscopía/estadística & datos numéricos , Aprendizaje Automático , Movimiento (Física) , Fantasmas de Imagen , Procedimientos Quirúrgicos Robotizados/instrumentación , Procedimientos Quirúrgicos Robotizados/estadística & datos numéricos , Técnicas de Sutura , Porcinos
2.
Rep U S ; 2021: 757-764, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-38170110

RESUMEN

This paper reports the design and evaluation of a novel piezo based actuator for needle drive in autonomous Deep Anterior Lamellar Keratoplasty (piezo-DALK). The actuator weighs less than 8g and is 20mm × 20mm × 10.5mm in size, making it ideal for eye-mounted applications. Mean open loop positional deviation was 1.17 ± 3.15um, and system repeatability and accuracy were 17.16um and 18.33um, respectively. Stall force was found to vary linearly with the cooling cycle and the actuator achieved a maximum drive force of 3.98N. When simulating the DALK procedure in synthetic corneal tissue, the piezo-DALK achieved a penetration depth of 643.56um which was equivalent to 92.1% of the total corneal thickness. This correlated closely with our desired depth of 90% ± 5% and took 2.5 hours to achieve. This work represents the first eye mountable actuator capable of "Big Bubble" needle drive for autonomous DALK procedures.

3.
Nanoscale ; 12(45): 22952-22957, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-33196715

RESUMEN

We present photocatalytically active, stable polymer-amorphous-MoS3-nanoparticle hybrid structures in aqueous solution. Below 10 nm MoS3 particles in the polymer exhibit an up to 7.5-fold increased photocatalytic activity compared to the neat nanoparticles without any additional photosensitizer. Supramolecular interactions are key in directing the structure formation of the hybrid assembly. The hybrid structures bear potential as novel affordable photocatalysts for solar energy conversion.

4.
Kardiologiia ; 60(10): 38-46, 2020 Nov 12.
Artículo en Ruso | MEDLINE | ID: mdl-33228504

RESUMEN

Aim      To compare the accuracy of predicting an in-hospital fatal outcome for models based on current machine-learning technologies in patients with ischemic heart disease (IHD) after coronary bypass (CB) surgery.Material and methods  A retrospective analysis of 866 electronic medical records was performed for patients (685 men and 181 women) who have had a CB surgery for IHD in 2008-2018. Results of clinical, laboratory, and instrumental evaluations obtained prior to the CB surgery were analyzed. Patients were divided into two groups: group 1 included 35 (4 %) patients who died within the first 20 days of CB, and group 2 consisted of 831 (96 %) patients with a beneficial outcome of the surgery. Predictors of the in-hospital fatal outcome were identified by a multistep selection procedure with analysis of statistical hypotheses and calculation of weight coefficients. For construction of models and verification of predictors, machine-learning methods were used, including the multifactorial logistic regression (LR), random forest (RF), and artificial neural networks (ANN). Model accuracy was evaluated by three metrics: area under the ROC curve (AUC), sensitivity, and specificity. Cross validation of the models was performed on test samples, and the control validation was performed on a cohort of patients with IHD after CB, whose data were not used in development of the models.Results The following 7 risk factors for in-hospital fatal outcome with the greatest predictive potential were isolated from the EuroSCORE II scale: ejection fraction (EF) <30 %, EF 30-50 %, age of patients with recent MI, damage of peripheral arterial circulation, urgency of CB, functional class III-IV chronic heart failure, and 5 additional predictors, including heart rate, systolic blood pressure, presence of aortic stenosis, posterior left ventricular (LV) wall relative thickness index (RTI), and LV relative mass index (LVRMI). The models developed by the authors using LR, RF and ANN methods had higher AUC values and sensitivity compared to the classical EuroSCORE II scale. The ANN models including the RTI and LVRMI predictors demonstrated a maximum level of prognostic accuracy, which was illustrated by values of the quality metrics, AUC 93 %, sensitivity 90 %, and specificity 96 %. The predictive robustness of the models was confirmed by results of the control validation.Conclusion      The use of current machine-learning technologies allowed developing a novel algorithm for selection of predictors and highly accurate models for predicting an in-hospital fatal outcome after CB.


Asunto(s)
Puente de Arteria Coronaria , Enfermedad Coronaria , Femenino , Mortalidad Hospitalaria , Humanos , Aprendizaje Automático , Masculino , Estudios Retrospectivos
5.
IUCrJ ; 7(Pt 2): 331-341, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32148860

RESUMEN

During single-crystal-to-single-crystal (SCSC) phase transitions, a polymorph of a compound can transform to a more stable form while remaining in the solid state. By understanding the mechanism of these transitions, strategies can be developed to control this phenomenon. This is particularly important in the pharmaceutical industry, but also relevant for other industries such as the food and agrochemical industries. Although extensive literature exists on SCSC phase transitions in inorganic crystals, it is unclear whether their classications and mechanisms translate to molecular crystals, with weaker interactions and more steric hindrance. A comparitive study of SCSC phase transitions in aliphatic linear-chain amino acid crystals, both racemates and quasi-racemates, is presented. A total of 34 transitions are considered and most are classified according to their structural change during the transition. Transitions without torsional changes show very different characteristics, such as transition temperature, enthalpy and free energy, compared with transitions that involve torsional changes. These differences can be rationalized using classical nucleation theory and in terms of a difference in mechanism; torsional changes occur in a molecule-by-molecule fashion, whereas transitions without torsional changes involve cooperative motion with multiple molecules at the same time.

6.
Khirurgiia (Mosk) ; (1): 14-24, 2020.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-31994495

RESUMEN

OBJECTIVE: Adjustment of diagnostics and management of the surgical treatment of patients with intraductal papillary mucinous tumor of pancreas. MATERIAL AND METHODS: From 2012 to 2018, 45 patients with intraductal papillary mucinous tumor were observed. During the observation the ultrasound examination, contrast-enhanced computed tomography and magnetic resonance tomography with contrast were used. In 29 cases radical surgery was performed, nonradical in 1 case; case follow-up is chosen for 15 patients. RESULTS: Intraductal papillary mucinous tumor was diagnosed and the definition of the type of tumor was made on the base of 2 types of imaging methods. Intraductal papillary mucinous tumor type 1 was founded in 5 (11%), whereas intraductal papillary mucinous tumor type 2 was founded in 20 (44,5%) and intraductal papillary mucinous tumor type 3 was observed in 20 (44,5%) cases. Intraductal papillary mucinous tumor associated with carcinoma was observed in 16 cases. Pancreaticoduodenal resection was performed in 20, distal exsection of pancreas was performed in 4 cases (2 in open manner access, 2 in robot-assisted manner), pancreatic head resection was performed in 3 cases (1 in open manner access, 2 in laparoscopic access) and in 2 cases the duodenopancreatectomy was performed. Explorative laparotomy was performed in case of intraductal papillary mucinous tumor type 2 associated with mucilaginous carcinoma and miliary metastasis in the liver. Early postoperative complications were observed in 5 cases (16, 6%): biliary fistula (n=2), postoperative wound infection (n=2), arrosive hemorrhage type B in ISGPS (n=1, was treated in an X-ray endovascular manner). Case follow-up was chosen in 15 cases of intraductal papillary mucinous tumor over the course of 6 to 74 months and disease progression was not observed. CONCLUSION: Intraductal papillary mucinous tumor is a condition associated with high risk of malignant change and demands early disease detection. The treatment should be provided in medical centers that specialize in the pancreas deceases, where a full patient examination as well as a clear-eyed understanding of diagnostic information with the execution of desirable type of surgical intervention with the guaranty of achievement R0 condition can be offered.


Asunto(s)
Neoplasias Intraductales Pancreáticas/diagnóstico , Neoplasias Intraductales Pancreáticas/cirugía , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirugía , Humanos , Páncreas/patología , Páncreas/cirugía , Pancreatectomía/efectos adversos , Neoplasias Intraductales Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Pancreaticoduodenectomía/efectos adversos
7.
IEEE Trans Med Robot Bionics ; 1(4): 228-236, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33458603

RESUMEN

Autonomous robotic surgery systems aim to improve patient outcomes by leveraging the repeatability and consistency of automation and also reducing human induced errors. However, intraoperative autonomous soft tissue tracking and robot control still remains a challenge due to the lack of structure, and high deformability of such tissues. In this paper, we take advantage of biocompatible Near-Infrared (NIR) marking methods and develop a supervised autonomous 3D path planning, filtering, and control strategy for our Smart Tissue Autonomous Robot (STAR) to enable precise and consistent incisions on complex 3D soft tissues. Our experimental results on cadaver porcine tongue samples indicate that the proposed strategy reduces surface incision error and depth incision error by 40.03% and 51.5%, respectively, compared to a teleoperation strategy via da Vinci. Furthermore, compared to an autonomous path planning method with linear interpolation between the NIR markers, the proposed strategy reduces the incision depth error by 48.58% by taking advantage of 3D tissue surface information.

8.
Med Image Comput Comput Assist Interv ; 11768: 65-73, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33521798

RESUMEN

Autonomous robotic anastomosis has the potential to improve surgical outcomes by performing more consistent suture spacing and bite size compared to manual anastomosis. However, due to soft tissue's irregular shape and unpredictable deformation, performing autonomous robotic anastomosis without continuous tissue detection and three-dimensional path planning strategies remains a challenging task. In this paper, we present a novel three-dimensional path planning algorithm for Smart Tissue Autonomous Robot (STAR) to enable semi-autonomous robotic anastomosis on deformable tissue. The algorithm incorporates (i) continuous detection of 3D near infrared (NIR) markers manually placed on deformable tissue before the procedure, (ii) generating a uniform and consistent suture placement plan using 3D path planning methods based on the locations of the NIR markers, and (iii) updating the remaining suture plan after each completed stitch using a non-rigid registration technique to account for tissue deformation during anastomosis. We evaluate the path planning algorithm for accuracy and consistency by comparing the anastomosis of synthetic vaginal cuff tissue completed by STAR and a surgeon. Our test results indicate that STAR using the proposed method achieves 2.6 times better consistency in suture spacing and 2.4 times better consistency in suture bite sizes than the manual anastomosis.

9.
IEEE Int Conf Robot Autom ; 2019: 1541-1547, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-33628614

RESUMEN

Compared to open surgical techniques, laparoscopic surgical methods aim to reduce the collateral tissue damage and hence decrease the patient recovery time. However, constraints imposed by the laparoscopic surgery, i.e. the operation of surgical tools in limited spaces, turn simple surgical tasks such as suturing into time-consuming and inconsistent tasks for surgeons. In this paper, we develop an autonomous laparoscopic robotic suturing system. More specific, we expand our smart tissue anastomosis robot (STAR) by developing i) a new 3D imaging endoscope, ii) a novel actuated laparoscopic suturing tool, and iii) a suture planning strategy for the autonomous suturing. We experimentally test the accuracy and consistency of our developed system and compare it to sutures performed manually by surgeons. Our test results on suture pads indicate that STAR can reach 2.9 times better consistency in suture spacing compared to manual method and also eliminate suture repositioning and adjustments. Moreover, the consistency of suture bite sizes obtained by STAR matches with those obtained by manual suturing.

10.
Khirurgiia (Mosk) ; (9): 74-76, 2018.
Artículo en Ruso | MEDLINE | ID: mdl-30307426

RESUMEN

A rare case of virsungorrhagia in a 65 y/o patient with a mucinous tumor of the tail of the pancreas is presented. Recurrent gastrointestinal bleeding was associated with an arrosis of the splenic artery adjacent to the tumor, which required a two-step treatment - endovascular occlusion of the splenic artery and distal resection of the pancreas.


Asunto(s)
Cistoadenoma Mucinoso/cirugía , Hemorragia Gastrointestinal/cirugía , Neoplasias Pancreáticas/cirugía , Arteria Esplénica/cirugía , Anciano , Cistoadenoma Mucinoso/complicaciones , Procedimientos Endovasculares , Hemorragia Gastrointestinal/etiología , Humanos , Páncreas/irrigación sanguínea , Páncreas/cirugía , Pancreatectomía , Neoplasias Pancreáticas/complicaciones , Recurrencia , Arteria Esplénica/patología , Oclusión Terapéutica
11.
Phys Rev Lett ; 121(10): 102501, 2018 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-30240248

RESUMEN

Differences in mean-square nuclear charge radii of ^{100-130}Cd are extracted from high-resolution collinear laser spectroscopy of the 5s ^{2}S_{1/2}→5p ^{2}P_{3/2} transition of the ion and from the 5s5p ^{3}P_{2}→5s6s ^{3}S_{1} transition in atomic Cd. The radii show a smooth parabolic behavior on top of a linear trend and a regular odd-even staggering across the almost complete sdgh shell. They serve as a first test for a recently established new Fayans functional and show a remarkably good agreement in the trend as well as in the total nuclear charge radius.

12.
Rep U S ; 2018: 1268-1275, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31475075

RESUMEN

Autonomous robotic assisted surgery (RAS) systems aim to reduce human errors and improve patient outcomes leveraging robotic accuracy and repeatability during surgical procedures. However, full automation of RAS in complex surgical environments is still not feasible and collaboration with the surgeon is required for safe and effective use. In this work, we utilize our Smart Tissue Autonomous Robot (STAR) to develop and evaluate a shared control strategy for the collaboration of the robot with a human operator in surgical scenarios. We consider 2D pattern cutting tasks with partial blood occlusion of the cutting pattern using a robotic electrocautery tool. For this surgical task and RAS system, we i) develop a confidence-based shared control strategy, ii) assess the pattern tracking performances of manual and autonomous controls and identify the confidence models for human and robot as well as a confidence-based control allocation function, and iii) experimentally evaluate the accuracy of our proposed shared control strategy. In our experiments on porcine fat samples, by combining the best elements of autonomous robot controller with complementary skills of a human operator, our proposed control strategy improved the cutting accuracy by 6.4%, while reducing the operator work time to 44 % compared to a pure manual control.

13.
J Oral Rehabil ; 44(12): 925-933, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28853162

RESUMEN

Patients with temporomandibular disorder (TMD) report poor sleep quality on the Pittsburgh Sleep Quality Index (PSQI). However, polysomnographic (PSG) studies show meagre evidence of sleep disturbance on standard physiological measures. The present aim was to analyse self-reported sleep quality in TMD as a function of myofascial pain, PSG parameters and depressive symptomatology. PSQI scores from 124 women with myofascial TMD and 46 matched controls were hierarchically regressed onto TMD presence, ratings of pain intensity and pain-related disability, in-laboratory PSG variables and depressive symptoms (Symptoms Checklist-90). Relative to controls, TMD cases had higher PSQI scores, representing poorer subjective sleep and more depressive symptoms (both P < 0·001). Higher PSQI scores were strongly predicted by more depressive symptoms (P < 0·001, R2 = 26%). Of 19 PSG variables, two had modest contributions to higher PSQI scores: longer rapid eye movement latency in TMD cases (P = 0·01, R2 = 3%) and more awakenings in all participants (P = 0·03, R2 = 2%). After accounting for these factors, TMD presence and pain ratings were not significantly related to PSQI scores. These results show that reported poor sleep quality in TMD is better explained by depressive symptoms than by PSG-assessed sleep disturbances or myofascial pain. As TMD cases lacked typical PSG features of clinical depression, the results suggest a negative cognitive bias in TMD and caution against interpreting self-report sleep measures as accurate indicators of PSG sleep disturbance. Future investigations should take account of depressive symptomatology when interpreting reports of poor sleep.


Asunto(s)
Depresión/complicaciones , Depresión/psicología , Síndromes del Dolor Miofascial/complicaciones , Polisomnografía , Autoinforme , Trastornos del Sueño-Vigilia/fisiopatología , Trastornos del Sueño-Vigilia/psicología , Trastornos de la Articulación Temporomandibular/complicaciones , Adulto , Análisis de Varianza , Electromiografía , Femenino , Humanos , Persona de Mediana Edad , Síndromes del Dolor Miofascial/fisiopatología , Síndromes del Dolor Miofascial/psicología , Dimensión del Dolor , Estudios Retrospectivos , Trastornos de la Articulación Temporomandibular/fisiopatología , Trastornos de la Articulación Temporomandibular/psicología , Factores de Tiempo
15.
Khirurgiia (Mosk) ; (4): 36-40, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-28418366

RESUMEN

AIM: To define the indications for pancreatoduodenectomy using 3D CT-imaging, to calculate the volume of damaged and intact tissues and to determine type of surgery depending on severity of disease in case of ductal pancreatic adenocarcinoma. MATERIAL AND METHODS: Retrospective analysis of CT-scans of 30 patients with ductal pancreatic adenocarcinoma was performed. In groups 1 and 2 by 15 patients total pancreatectomy and pancreatoduodenectomy were made respectively. All patients underwent contrast-enhanced CT examination (Brilliance iCT, Phillips) followed post-processing on Brilliance Workspace Portal platform. All data were assessed by two reviewers. RESULTS: In group 1 CT volume of the tumor was 24±19 cm3 (32% of total pancreas), in group 2 - 9.8±6 cm3 (16% of total pancreas). CT-volume of celiacomesenteric arteries and portal system was 25.8±10 mm/59.5±18.9 mm and 23.3±6/49.9±14.7 mm in groups 1 and 2 respectively. Greater volume of tumor was significantly associated with increased portal system (p<0.03). Sensitivity, specificity and accuracy of determining of tumor location were increased up to 94%, 50% and 80% respectively in group 1. There were no cases of wrong localization in group 2. Data of both reviewers were similar. CONCLUSION: Total pancreatectomy is advisable for pancreatic adenocarcinoma if its volume is over 31.8% of total pancreas according to 3D CT-scans. 3D-modeling improves preoperative assessment of resectability, accuracy of determining of tumor localization and identifying vascular invasion.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico por imagen , Carcinoma Ductal Pancreático/cirugía , Imagenología Tridimensional , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Tomografía Computarizada por Rayos X , Carcinoma Ductal Pancreático/patología , Arteria Celíaca/diagnóstico por imagen , Arteria Celíaca/cirugía , Humanos , Arterias Mesentéricas/diagnóstico por imagen , Arterias Mesentéricas/cirugía , Invasividad Neoplásica/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Pancreaticoduodenectomía , Sistema Porta/diagnóstico por imagen , Sistema Porta/cirugía , Vena Porta/diagnóstico por imagen , Vena Porta/cirugía , Estudios Retrospectivos , Carga Tumoral
17.
Khirurgiia (Mosk) ; (6): 14-29, 2016.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-27296118

RESUMEN

AIM: To optimize the diagnosis and surgical treatment of insulinoma and nesidioblastosis. MATERIAL AND METHODS: 42 patients with organic hyperinsulinism (OH) were operated. There were 39 cases of insulinoma including 2 patients with insulinoma combined with nesidioblastosis and 3 cases of nesidioblastosis alone. Preoperative ray imaging consisted of percutaneous, endoscopic and intraoperative sonography, contrast-enhanced computed tomography, magnetic resonance imaging (MRI). Functional test included arterial-stimulated blood sampling (ASBS). Laparotomy and robot-assisted techniques were used in 22 and 20 patients. RESULTS: Sensitivity was 62.0%, 76.9%, 83.3%, 87.5%, 94.8% and 100% in percutaneous sonography, CT, endoscopic sonography, MRI, intraoperative sonography and ASBS respectively. Postoperative complications were observed in 14 and 6 patients after conventional and robot-assisted surgery. 2 patients died. Overall mortality was 4.8%. None patient had recurrent hypoglycemic conditions in long-term postoperative period (mean follow-up 18.7 months). CONCLUSIONS: Comprehensive survey allowed to define the cause of OH. Minimally invasive organ-sparing surgery has satisfactory immediate and remote results in these patients.


Asunto(s)
Hiperinsulinismo , Insulinoma , Pancreatectomía , Neoplasias Pancreáticas , Complicaciones Posoperatorias , Adulto , Diagnóstico Diferencial , Endosonografía/métodos , Femenino , Humanos , Hiperinsulinismo/diagnóstico , Hiperinsulinismo/etiología , Hiperinsulinismo/fisiopatología , Hiperinsulinismo/terapia , Hipoglucemia/diagnóstico , Hipoglucemia/etiología , Insulinoma/patología , Insulinoma/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Moscú , Pancreatectomía/efectos adversos , Pancreatectomía/métodos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/prevención & control , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
18.
Phys Rev Lett ; 116(3): 032501, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26849588

RESUMEN

Isomer shifts have been determined in ^{111-129}Cd by high-resolution laser spectroscopy at CERN-ISOLDE. The corresponding mean square charge-radii changes, from the 1/2^{+} and the 3/2^{+} ground states to the 11/2^{-} isomers, have been found to follow a distinct parabolic dependence as a function of the atomic mass number. Since the isomers have been previously associated with simplicity due to the linear mass dependence of their quadrupole moments, the regularity of the isomer shifts suggests a higher order of symmetry affecting the ground states in addition. A comprehensive description assuming nuclear deformation is found to accurately reproduce the radii differences in conjunction with the known quadrupole moments. This intuitive interpretation is supported by covariant density functional theory.

19.
Adv Healthc Mater ; 5(3): 319-325, 2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26627057

RESUMEN

Congenital heart defect interventions may benefit from the fabrication of patient-specific vascular grafts because of the wide array of anatomies present in children with cardiovascular defects. 3D printing is used to establish a platform for the production of custom vascular grafts, which are biodegradable, mechanically compatible with vascular tissues, and support neotissue formation and growth.


Asunto(s)
Materiales Biocompatibles/química , Polímeros/química , Animales , Prótesis Vascular , Células Cultivadas , Humanos , Ratones , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Andamios del Tejido
20.
J Oral Rehabil ; 42(10): 751-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26010126

RESUMEN

Sleep bruxism (SB), primarily involving rhythmic grinding of the teeth during sleep, has been advanced as a causal or maintenance factor for a variety of oro-facial problems, including temporomandibular disorders (TMD). As laboratory polysomnographic (PSG) assessment is extremely expensive and time-consuming, most research testing this belief has relied on patient self-report of SB. The current case-control study examined the accuracy of those self-reports relative to laboratory-based PSG assessment of SB in a large sample of women suffering from chronic myofascial TMD (n = 124) and a demographically matched control group without TMD (n = 46). A clinical research coordinator administered a structured questionnaire to assess self-reported SB. Participants then spent two consecutive nights in a sleep laboratory. Audiovisual and electromyographic data from the second night were scored to assess whether participants met criteria for the presence of 2 or more (2+) rhythmic masticatory muscle activity episodes accompanied by grinding sounds, moderate SB, or severe SB, using previously validated research scoring standards. Contingency tables were constructed to assess positive and negative predictive values, sensitivity and specificity, and 95% confidence intervals surrounding the point estimates. Results showed that self-report significantly predicted 2+ grinding sounds during sleep for TMD cases. However, self-reported SB failed to significantly predict the presence or absence of either moderate or severe SB as assessed by PSG, for both cases and controls. These data show that self-report of tooth grinding awareness is highly unlikely to be a valid indicator of true SB. Studies relying on self-report to assess SB must be viewed with extreme caution.


Asunto(s)
Bruxismo del Sueño/diagnóstico , Síndrome de la Disfunción de Articulación Temporomandibular/complicaciones , Estudios de Casos y Controles , Femenino , Humanos , Polisomnografía/métodos , Reproducibilidad de los Resultados , Autoinforme , Sensibilidad y Especificidad , Bruxismo del Sueño/complicaciones
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