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Large-sized cranial bone defect repair presents a great challenge in the clinic. The ideal cranioplasty materials to realize the functional and cosmetic recovery of the defect must have sufficient mechanical support, excellent biocompatibility, good osseointegration and biodegradability as well. In this study, a high-strength mineralized collagen (MC) bone scaffold was developed with biomimetic composition, microstructure and mechanical properties for the repair of sheep large-sized cranial bone defects in comparison with two traditional cranioplasty materials, polymethyl methacrylate and titanium mesh. The compact MC scaffold showed no distinct pore structure and therefore possessed good mechanical properties. The strength and elastic modulus of the scaffold were much higher than those of natural cancellous bone and slightly lower than those of natural compact bone. In vitro cytocompatibility evaluation revealed that the human bone marrow mesenchymal stem cells (hBMSC) had good viability, attachment and proliferation on the compact MC scaffold indicating its excellent biocompatibility. An adult sheep cranial bone defect model was constructed to evaluate the performances of these cranioplasty materials in repairing the cranial bone defects. The results were investigated by gross observation, computed tomography scanning as well as histological assessments. The in vivo evaluations indicated that compact MC scaffold showed notable osteoconductivity and osseointegration with surrounding cranial bone tissues by promoting bone regeneration. Our results suggested that the compact MC scaffold has a promising potential for large-sized cranial bone defect repair.

The specifications performance data for the latest generation system are compared to prior generations. These results are shown for both missing pattern (or hard) and unknown contamination (or soft) defects of various classifications in different patterns. For hard defects, capability will be demonstrated down to the 65 nm node, with soft defect repair and clean significantly exceeding to even smaller nodes down to 14 nm. The latter is of particular note, especially in the application of the cleaning of fall-on unknown contaminates on pelliclized photomasks. Finally, there will be a discussion of future work to further develop soft repair/clean process and laser processes for other mask technologies.

The specifications performance data for the latest generation system are compared to prior generations. These results are shown for both missing pattern (or hard) and unknown contamination (or soft) defects of various classifications in different patterns. For hard defects, capability will be demonstrated down to the 65 nm node, with soft defect repair and clean significantly exceeding to even smaller nodes down to 14 nm. The latter is of particular note, especially in the application of the cleaning of fall-on unknown contaminates on pelliclized photomasks. Finally, there will be a discussion of future work to further develop soft repair/clean process and laser processes for other mask technologies.

Background: This study aimed to investigate the specific causes for switching patients from minimally invasive transthoracic occlusion to surgical repair under cardiopulmonary bypass (CPB). By retrospectively analyzing 340 cases, we sought to provide the clinical reference for improving the success rate of minimally invasive transthoracic device closure of ventricular septal defect (VSD). Methods: Among the 340 patients who underwent transthoracic closure of VSDs in the past 3 years at our hospital, 26 patients needed to be switched to surgical repair under CPB due to failure of transthoracic closure. We investigated the causes by retrospectively analyzing the findings from preoperative transthoracic echocardiography (TTE), intraoperative transesophageal echocardiography (TEE) and surgical exploration. Results: Among the 340 patients who underwent transthoracic closure of VSDs, 26 patients (7.65%) were switched to surgical repair under CPB, which included 11 cases of membranous aneurysm (13.10%), 13 cases of perimembranous type (6.22%) and 2 cases of intracristal type (5.00%) according to their anatomic classifications. Among the 186 patients who underwent transthoracic closure during the first 17 months, 20 patients (10.75%) were switched to surgical repair under CPB. The main causes were failure of the delivery system to pass through the VSD in 7 patients, obvious residual shunts after releasing the occluder in 5 patients, significant shedding or shifting after releasing the occluder in 4 patients, significant regurgitation in adjacent valves in 3 patients and severe intraoperative complication (bleeding) in 1 patient. Among the 154 patients who underwent transthoracic closure during the late 17 months, 6 patients (3.90%) were switched to surgical repair under cardiopulmonary bypass. The main causes were significant residual shunts after releasing the occluder in 3 patients, significant regurgitation in adjacent valves in 2 patients after releasing the occluder and failure of the delivery system to pass through the VSD in 1 patient. Conclusions: Among all the anatomic classifications, membranous aneurysm VSD had the highest risk for switching from minimally invasive transthoracic closure to surgical repair under CPB. During the early period, the surgeons were not yet skilled with the minimally invasive transthoracic closure procedure, and the main causes of switching to surgical repair under CPB were that the delivery system could not pass through the ventricular septal defect and significant residual shunts persisted after releasing the occluder. In contrast, in the late period, the surgeons were skilled with the minimally invasive transthoracic closure procedure, and the main causes were significant residual shunts and obvious regurgitation in adjacent valves after releasing the occluder.

Animal assays represent an important stage between in vitro studies and human clinical applications. These models are crucial for biomedical research and regenerative medicine studies, as these offer precious information for systematically assessing the efficacy and risks of recently created biomaterials, medical devices, drugs, and therapeutic modalities prior to initiation of human clinical trials. Therefore, selecting a suitable experimental model for tissue engineering purposes is essential to establish valid conclusions. However, it remains important to be conscious of the advantages and limitations of the various small and large animal models frequently used for biomedical research as well as the different challenges encountered in extrapolating data obtained from animal studies and the risks of misinterpretation. This chapter discusses the various small animal model strategies used for osteochondral defect repair. Particular emphasis will be placed on analyzing the materials and strategies used in each model.

Acute traumatic posterior glenohumeral dislocations are rare; they are typically caused by high-velocity trauma, epileptic seizures, or electrocution1,2. Anterior impression fractures of the humeral head (reverse Hill-Sachs defect) occur in over 80% of individuals following a posterior dislocation of the shoulder3. The size of reverse Hill-Sachs defects varies and has been reported to be as large as 55% of the cartilage surface4. Defects affecting less than 10% of the articular surface can be treated conservatively with closed reduction, and immobilization may produce excellent stability with a low risk for redislocation1. However, traditional sling immobilization in internal rotation puts the shoulder at risk to redislocate. Therefore, surgical treatment is recommended in defects that affect between 10% and 20% of the articular surface; they can be treated either with an arthroscopic approach, open remplissage, bone-grafting, or prosthetic replacement5. Compared with traditional posterior Hill-Sachs defects that occur with anterior dislocations, the extent of osseous and cartilaginous destruction of the anterior humeral head is usually more extensive in reverse Hill-Sachs defects6. Therefore, to stabilize the glenohumeral joint and avoid potential progressive cartilage destruction, which may lead to early osteoarthritis, reverse Hill-Sachs defects affecting more than 20% of the articular surface are nearly always treated surgically7. Several techniques have been described, including subscapularis transfer with or without the lesser tuberosity into the humeral head defect, disimpaction and bone-grafting, allograft reconstruction of the humeral articular surface, and arthroplasty8. If the joint becomes unstable, repair of the posterior capsulolabral structures can be performed to restore stability, as described for treatment of symptomatic posterior subluxation9,10. Large defects of greater than 40% of the articular surface typically require initial arthroplasty because of the increased risk of osteoarthritis, …

Aim at the surface defects found in the quality inspection of marine anchors, structural features of anchors and factors affecting the forming process were analyzed, the typical defects found in the quality inspection of ship anchor were mainly studied, including cracks, blowhole, shrinkage hole, slag, sand casting residual stress and etc., the reasons of various surface defects were analyzed base on an example of stockless anchors, and several aspects of defect repairs focused on are pointed out.

Iatrogenic aortic valve (AV) perforation during non-aortic cardiac operations is a rare complication. The suture-related inadvertent injury to an AV leaflet can produce leaflet perforation with aortic regurgitation after ventricular septal defect repair (VSDR). We report three consecutive patients who had iatrogenic aortic leaflet perforation during VSDR in other hospitals and referred to our hospital for reoperation. In all three cases, the perforated AV leaflets were preserved and repaired by autologous pericardial patch or direct local closure.

Articular cartilage (AC) defects lack the ability to self-repair due to their avascular nature and the declined mitotic ability of mature chondrocytes. To date, cartilage tissue engineering using implanted scaffolds containing cells or growth factors is the most promising defect repair method. Scaffolds for cartilage tissue engineering have been comprehensively researched. As a promising scaffold biomaterial for AC defect repair, the properties of chitosan are summarized in this review. Strategies to composite chitosan with other materials, such as polymers (including collagen, gelatin, alginate, silk fibroin, poly-caprolactone, and poly-lactic acid) and bioceramics (including calcium phosphate, calcium polyphosphate, and hydroxyapatite) are presented. Methods to manufacture three-dimensional porous structures to support cell attachment and nutriment exchange have also been included.

To deliver a defect-free photomask, is an essential step of mask manufacturing. EB (Electron-beam) repair is widely applied to deal with defects on photomasks, and has to cover etch and deposition capabilities without any pattern damage. However, mask repair is facing more challenges, with the shrinkage of minimum feature resolution for advanced technology nodes. Especially for micro defects at the edge of wafer printability specifications, differences between defect and reference may be tiny and hard to distinguish in visual or by existing methods on repair tools, so that it was difficult to start. In this paper, a new approach named Contour-based 2D Metrology will be introduced as assistance for the repair processes of such challenging micro defects. Both CDSEM images of defect and reference are input for extracting; then contour-based patterns are overlapped for each other and compared with GDS as well, to describe quantitative differences for each micro area. Assisted with such rigorous and comprehensive data analysis, micro defects can be accurately positioned according to Aims Results and repair processes would be proceeding.

This study aims to improve plans by analyzing spatial compositions of cohousing common houses, their role depending on the types of users and spaces, and satisfaction from the user-oriented design perspective. For this study, a basic concept was examined based on previous studies and literature reviews. So-Haeng-Ju(Happy House with Communication) Houses 1, 2, and 3 in Seongmisan Village was analyzed. As well, interviews with residents of these house were conducted to analyze the role of user behavior in common house depending on the types of users and spaces. As a result, it was found that there were common characteristics of roles in an exchange with neighbors, cooperative child-care, and residents` meeting. The time and behavioral types were different depending on the living patterns, characteristics, and family members of resident. User satisfaction with the locations of community facilities including communal kitchen and communal living room, the composition of rooms, communication with residents, and the connection between communal living space and personal living space, was above the average. However user satisfaction with storage facilities, or defect repair and facility maintenance was low. Most of cohousing common house user were satisfied with the use and size of spaces, and a sense of community, including communication with neighbors beyond the environment and Seongmisan Village. In conclusion, a realistic alternative is required for future cohousing by developing a system regarding human resources networks and cost bearing issues.

The osteochondral defects caused by vigorous trauma or physical disease are difficult to be managed. Tissue engineering provides a possible option to regenerate the damaged osteochondral tissues. For osteochondral reconstruction, one intact scaffold should be considered to support the regeneration of both cartilage and subchondral bone. Therefore, the biphasic scaffolds with the mimic structures of osteochondral tissues have been developed to close this chasm. A variety of biomimetic bilayer scaffolds fabricated from natural or synthetic polymers, or the ones loading with growth factors, cells, or both of them make great progresses in osteochondral defect repair. In this review, the preparation and in vitro and/or in vivo verification of bioinspired biphasic scaffolds are summarized and discussed, as well as the prospect is predicted.

Incomplete P1 scribing lines between neighboring Mo back electrodes in Copper indium gallium selenide: Cu(In,Ga)Se 2 (CIGS) thin-film modules have been repaired by removing the Mo remnants in the P1 laser line. The repair is achieved by melting and evaporating the Mo remnant with an electrical current. We develop a repair process that is robust to different lengths of the P1 line interruption, to arbitrary defect positions and defect numbers both within one scribing line and the complete module. Furthermore, the repair method provides a reliable feedback about a successful defect repair, whereby affected P1 scribing lines can be located and defects can be counted.

This work is focused on analysis of mechanical behaviour of aircraft engine’s sound-absorbing panels (SAPs) exposed to in-service damage. Its aim is to suggest techniques of local repair of damaged SAPs and estimation of their post-repair residual strength. Fibreglass laminate panels with tubular core and perforated elements were studied for this purpose. A mechanical behaviour of structural elements of the panels was modelled with the finite-element (FE) analysis, with through rupture considered as an in-service defect. A technique of defect repair without dismantling parts from the structure is introduced using a novel vacuumless technology. This procedure was implemented on specially produced samples and simulated with FE. Residual strength of repaired samples was compared with that of standard and ruptured ones in tension experiments and FE analysis. Conclusions about applicability limits of the presented method are provided.

The bones of the maxillary complex are vital for normal oro-nasal function and facial cosmetics. Maxillary tumor excision results in large defects that commonly include segments of the alveolar and palatine processes, compromising eating, speech and facial appearance. Unlike the conventional approach to maxillary defect repair by vascularized bone grafting, transport disc distraction osteogenesis (TDDO) stimulates new bone by separating the healing callus, and stimulates growth of surrounding soft tissues as well. Bone formed in this way closely mimics the parent bone in form and internal structure, producing a superior anatomical, functional and cosmetic result. Historically, TDDO has been successfully used to close small horizontal cleft defects in the maxilla, not exceeding 25 mm. Fujioka et al. reported in 2012 that "no bone transporter corresponding to the (large) size of the oro-antral fistula is marketed. The authors report the successful treatment of 4 cases involving alveolar defects of between 25 mm and 80 mm in length.

In this study, we introduce an alternative route for the synthesis of bioactive borate-phosphate glasses. Glasses with nominal compositions of xNa(2)O center dot yB(2)O(3)center dot zP(2)O(5) (x = 1, 2; y = 1/2; z = 1/2, 3/2) were obtained via melt-quench technique from B-O-P bonded materials prepared by organic-mediated synthesis. Analytical studies indicated that these glasses display different structural, thermal and surface characteristics compared to the known borophosphate glasses resulting from the orientation effect of the organic ligand present in the starting materials. In vitro bioactivity tests showed instant formation of amorphous calcium phosphates as apatite precursors. The unique properties of these newly-designed bioactive glasses might be improved for in situ bone regeneration and defect repair applications in orthopedics and dentistry. (C) 2014 Elsevier B.V. All rights reserved.

We report a 21-year-old patient with a ventricular septal defect (VSD) with an embolic vegetation on the tricuspid valve using a technique of septal leaflet detachment to facilitate the repair of the VSD. Although described in the pediatric patients, this technique has not been reported in adults. The technique of septal leaflet mobilization is described, along with other techniques of tricuspid leaflet mobilization that aid in VSD visualization and repair. Tricuspid leaflet detachment has application for adult surgeons repairing perimembranous, postinfarction, and iatrogenic VSD encountered in resection of subaortic stenosis.

Mechanical loading is an important aspect of post-surgical fracture care. The timing of load application relative to the injury event may differentially regulate repair depending on the stage of healing. Here, we used a novel mechanobiological model of cortical defect repair that offers several advantages including its technical simplicity and spatially confined repair program, making effects of both physical and biological interventions more easily assessed. Using this model, we showed that daily loading (5N peak load, 2Hz, 60 cycles, 4 consecutive days) during hematoma consolidation and inflammation disrupted the injury site and activated cartilage formation on the periosteal surface adjacent to the defect. We also showed that daily loading during the matrix deposition phase enhanced both bone and cartilage formation at the defect site, while loading during the remodeling phase resulted in an enlarged woven bone regenerate. All loading regimens resulted in abundant cellular proliferation throughout the regenerate and fibrous tissue formation directly above the defect demonstrating that all phases of cortical defect healing are sensitive to physical stimulation. Stress was concentrated at the edges of the defect during exogenous loading, and finite element (FE)-modeled longitudinal strain (ezz) values along the anterior and posterior borders of the defect (~2200μe) was an order of magnitude larger than strain values on the proximal and distal borders (~50-100μe). It is concluded that loading during the early stages of repair may impede stabilization of the injury site important for early bone matrix deposition, whereas loading while matrix deposition and remodeling are ongoing may enhance stabilization through the formation of additional cartilage and bone.

The lip cancers refer to the cancers occurred in the lip vermilion mucosa (the exposed lip vermilion mucosa when the lips are naturally closed) and the joint mucosa in the corner of the mouth (within the range of 1 cm backward from the oral fissure). The cancers occurred in the inner side of the lip mucosa belong to the category of buccal mucosa carcinoma. The vast majority of cancers occurred in the lip vermilion mucosa are squamous cell carcinomas, and most of them are better differentiated; a small part of lip cancers are the basal cell carcinomas, which are caused due to the fact that the lip skin is invaded, and the adenocarcinoma is rarely seen.

The tongue cancer is one of the more common oral malignant tumors, accounting for 32.3–50.6% of oral cancer. In China, the male to female prevalence ratio is 2:1; in foreign countries, the prevalence of tongue cancer is significantly greater in male than in female, and the male to female prevalence ratio is about 55:1. The disease mostly occurs in patients between 40 and 60 years, accounting for about 70%; the tongue cancer patients over 60 years of age are not uncommon; the tongue cancers in newborn babies and people under 20 years of age have been reported, but the tongue cancer patients under 40 years of age account for less than 3%.The patients with tongue cancers occurring in the lingual margin account for 60–70%, followed by the occurring places such as the ventral surface of the tongue, the tip of the tongue, and the dorsum of the tongue.

The penile cancer is the most common malignant penile tumor, accounting for 90–97.4% of malignant penile tumors. According to the statistics in Shanghai, the incidence rate of penile cancer is 1.09/100,000. With the improvement of living conditions and people’s increased awareness of health literacy, the incidence rate of penile cancer decreases year by year, and the penile cancer has become a kind of rare tumor. The average onset age of penile cancer is about 60 years old in China.

>In terms of the boundaries between the lower limbs and trunk, the front side is the inguinal ligament, the lateral outer side is all iliac crest, the rear side is the lateral margin of the sacrococcygeal bone, and the above interfaces form a continuous boundary to separate the lower limbs and trunk. The lower lateral side of this interface is the lower limb.

For the plastic surgeons, the nasal repair and reconstruction are one of the most challenging works, because that requires not only the reconstruction of a visually important and iconic facial organ but also the reconstruction of a functioning organ.

Damage to articular cartilage can over time cause degeneration to the tissue surrounding the injury. To address this problem, scaffolds that prevent degeneration and promote neotissue growth are needed. We introduce a new hybrid scaffold that combines a stereolithography-based three-dimensional printed support structure with an injectable and photopolymerizable hydrogel for delivering cells to treat focal chondral defects. In this proof of concept study, we demonstrate the ability to a) infill the support structure with an injectable hydrogel precursor solution, b) incorporate cartilage cells during infilling using a degradable hydrogel that promotes neotissue deposition, and c) minimize damage to the surrounding cartilage when the hybrid scaffold is placed in situ in a focal chondral defect in an osteochondral plug that is cultured under mechanical loading. With the ability to independently control the properties of the structure and the injectable hydrogel, this hybrid scaffold approach holds promise for treating chondral defects.

Caesarean scar defect (CSD) can cause postmenstrual bleeding. Defect repair is an effective technique to improve this symptom, but there are still a few patients getting little improvement. This retrospective study evaluates the efficacy of scar repair and explores the factors associated with poor effect. In total, 123 patients were involved in the final analysis. All of them complained about menstruation period7 days due to postmenstrual bleeding. Before surgery, 87.8% of patients had a menstruation period more than 10 days and 20.3% had a period more than 15 days. After surgery, a normal menstruation period ( =7 days) was achieved in 46.3% (95%CI 37.3%-55.6%) of patients and a menstruation period lasting no more than 10 days was achieved in 74.8% (95%CI 66.2%-82.2%). Through multivariate logistic analysis, four factors were found dependently associated with poor effect (defined as menstruation period10 days after surgery): repeated caesarean section (OR 9.75, 95%CI 2.30-41.36, 0.002) was a risk factor, while defect volume600 mm

Software is present in almost all economic activity, and is boosting economic growth from many perspectives. At the same time, like any other man-made artifacts, software suffers from various bugs which lead to incorrect results, deadlocks, or even crashes of the entire system. Several approaches have been proposed to aid debugging. An interesting recent research direction is automatic program repair, which achieves promising results towards the reduction of costs associated with defect repair in software maintenance. The identification of common bug fix patterns is important to generate program patches automatically. In this paper, we conduct an empirical study with more than 4 million bug fixing commits distributed among 101,471 Java projects hosted on GitHub. We used a domain-specific programming language called Boa to analyze ultra-large-scale data efficiently. With Boa’s support, we automatically detect the prevalence of the 5 most common bug fix patterns (identified in the work of Pan et al.) in those bug fixing commits.

Gore-Tex® is a widely used durable patch for repair of congenital diaphragmatic defects yet may result in complications. We compared Gore-Tex with a composite of a radial pore-orientated collagen scaffold (RP-Composite) and clinically used porcine small intestinal submucosa (SIS; Surgisis®) in a rabbit model for diaphragmatic hernia. The growing rabbit mimics the rapid rib cage growth and reherniation rates seen in children. We created and immediately repaired left hemidiaphragmatic defects in 6-week-old rabbits with Gore-Tex, SIS, and an RP-Composite scaffold. An additional group of rabbits had a sham operation. At 90 days, survivors more than doubled in weight. We observed few reherniations or eventrations in Gore-Tex (17%) and RP-Composite (22%) implanted animals. However, SIS failed in all rabbits. Maximum transdiaphragmatic pressure was lower in Gore-Tex (71%) than RP-Composite implanted animals (112%) or sham (134%). Gore-Tex repairs were less compliant than RP-Composite, which behaved as sham diaphragm (p

Facial plastic surgeons use a variety of reconstruction techniques to overcome challenges in restoring the function, structural integrity, and intricate nasal contour in nasal reconstruction. Local cutaneous flaps provide excellent skin texture, thickness, and color match in nasal reconstruction. They offer an excellent cosmetic appearance for small- to medium-sized defects and are preferentially utilized when feasible. This article aims to provide an updated review of local cutaneous flaps for nasal defect repair and describe the major principles related to flap selection.

The management of chondral defects has been a challenge for a long time because of the poor self-healing capacity of articular cartilage. Many approaches ranging from symptomatic treatment to structural cartilage regeneration are not that successful with very limited satisfactory results. Chondral defects caused by tumor, trauma, infection, congenital malformations are very common in clinical trials. It seriously affects the patient's physical function and quality of life. The appearance of cartilage tissue engineering has brought good news for cartilage defect repair. Through this review, we are aimed at reviewing the progress of the types and preparation techniques of scaffold materials in cartilage tissue engineering.

We report our experience of umbilical cutaneous “Y-to-V” plasty in surgical hernia repair about the infant and the child in Senegal. The procedure stands for hernia with diameters included in 2–5 cm and a height or cutaneous projection of at least 1.5 cm. The operation starts with pencil drawings and follows a primary incision of the vertical branch of the “Y” and a circular subcutaneous undermining. Then, herniorrhaphy is performed, and umbilical skin excess resected according to lateral twin isosceles triangle flaps, making the “V.” We perform subcutaneous quilting sutures of the umbilical residual flap and intradermal running suture of the wound. Aesthetic variables such as scar quality, shape, and depth of the new umbilical valley, aspects of peripheral landscape, are itemized and analyzed. The authors of this chapter highlight the need for aesthetic surgery together with parietal defect repair and give precise different umbilical cosmetic criteria.

The hybrid manufacturing process which integrates additive manufacturing with subtractive machining is competitive and promising in component repair. To automate this process, detecting the missing volume and generating the deposition tracks is the key. In this study, strategies for repairing defects on flat and non-flat surfaces were investigated. A cost-effective reverse engineering tool was utilized to reconstruct STL models of damaged objects. Point data of the fracture surface on flat surfaces was obtained to generate the tool path for material building up. For defects on non-flat surfaces, the damaged model was best-fitted with the nominal model. Then both models were sliced and by using area comparison method, the defective domain was detected. Then a series of projection rays were utilized to slice the damaged cross-sections to extract the repair volume. Finally, repair experiments were performed to assess the repair quality through repair automation.

Hypothesizing that the implantation of non-articular (heterotopic) chondrocytes might be an alternative approach to support articular cartilage repair, we analyzed joint cartilage defect healing in the rabbit model after implantation of autologous auricle-derived (auricular) chondrocytes. Autologous lapine articular and auricular chondrocytes were cultured for 3 weeks in polyglycolic acid (PGA) scaffolds before being implanted into critical sized osteochondral defects of the rabbit knee femoropatellar groove. Cell-free PGA scaffolds and empty defects served as controls. Construct quality was determined before implantation and defect healing was monitored after 6 and 12 weeks using vitality assays, macroscopical and histological score systems. Neo-cartilage was formed in the PGA constructs seeded with both articular and auricular chondrocytes in vitro and in vivo. At the histological level, cartilage repair was slightly improved when using autologous articular chondrocyte seeded constructs compared to empty defects and was significantly superior compared to defects treated with auricular chondrocytes 6 weeks after implantation. Although only the immunohistological differences were significant, auricular chondrocyte implantation induced an inferior healing response compared with the empty defects. Elastic auricular chondrocytes might maintain some tissue-specific characteristics when implanted into joint cartilage defects which limit its repair capacity.

The major limitation of current engineered myocardial patches for the repair of heart defects is that insulating polymeric scaffold walls hinder the transfer of electrical signals between cardiomyocytes. This loss in signal transduction results in arrhythmias when the scaffolds are implanted. We report that small, subtoxic concentrations of single-walled carbon nanotubes, on the order of tens of parts per million, incorporated in a gelatin–chitosan hydrogel act as electrical nanobridges between cardiomyocytes, resulting in enhanced electrical coupling, synchronous beating, and cardiomyocyte function. These engineered tissues achieve excitation conduction velocities similar to native myocardial tissue (22 ± 9 cm/s) and could function as a full-thickness patch for several cardiovascular defect repair procedures, such as right ventricular outflow track repair for Tetralogy of Fallot, atrial and ventricular septal defect repair, and other cardiac defects, without the risk of inducing cardiac arrhythmias.

Surgical repair of congenital heart disease during cardiopulmonary bypass is common, and performing these complicated procedures in the absence of blood transfusions is especially challenging. A case of a Jehovah's Witness child who underwent surgical repair of a ventricular septal defect utilizing a new tetrastarch for autologous normovolemic hemodilution is reported. A successful operative repair was achieved without the need for non-autologous blood transfusion.

Due to the small size of nanoscale devices, they are highly prone to process disturbances which results in manufacturing defects. Some of the defects are randomly distributed throughout the nanodevice layer. Other disturbances tend to be local and lead to cluster defects caused by factors such as layer misalignments, line width variations and contamination particles. In this paper, initially a method is proposed for separately identifying cluster defects from random ones. Subsequently a hardware repair structure is presented to repair the cluster defects with rectangular window transfer vectors using a range-matching content addressable memory (RM-CAM) and random defects using defect aware triple-modular redundancy (DA-TMR) columns. It is shown that a combination of these two approaches is more effective for repairing defects at higher error rates with an acceptable overhead. The effectiveness of the technique is shown by examining defect recovery results for different fault distribution scenarios. Also the mapping circuit hardware performance parameters are presented for various memory sizes and the speed, power dissipation and overhead factors are reported.

Objective To report a staged approach that includes selective dental extractions before definitive double-layer hard palate defect closure in dogs. Study Design Retrospective case series. Animals Dogs (n = 6) with a palatal defect. Methods Dogs had selective maxillary teeth extractions 4–8 weeks before definitive hard palate defect repair by double-layer local full-thickness mucosal flaps. Results All palatal defects were considered complex. Complete hard palate closure was achieved after initial attempt in 3 dogs; 2 dogs had revision surgery before complete closure, and in 1 dog, closure failed and further treatment was declined. No complications or long-term consequences were associated with selective dental extractions. Conclusions Selective dental extractions before definitive surgical repair using mucosal flaps in a double-layer approach is an effective alternative when treating complex hard palate defects in dogs.

Contains fulltext : 136446.pdf (Publisher’s version ) (Closed access) OBJECTIVE: To investigate the ability of cell-laden bilayered hydrogels encapsulating chondrogenically and osteogenically (OS) pre-differentiated mesenchymal stem cells (MSCs) to effect osteochondral defect repair in a rabbit model. By varying the period of chondrogenic pre-differentiation from 7 (CG7) to 14 days (CG14), the effect of chondrogenic differentiation stage on osteochondral tissue repair was also investigated. METHODS: Rabbit MSCs were subjected to either chondrogenic or osteogenic pre-differentiation, encapsulated within respective chondral/subchondral layers of a bilayered hydrogel construct, and then implanted into femoral condyle osteochondral defects. Rabbits were randomized into one of four groups (MSC/MSC, MSC/OS, CG7/OS, and CG14/OS; chondral/subchondral) and received two similar constructs bilaterally. Defects were evaluated after 12 weeks. RESULTS: All groups exhibited similar overall neo-tissue filling. The delivery of OS cells when compared to undifferentiated MSCs in the subchondral construct layer resulted in improvements in neo-cartilage thickness and regularity. However, the addition of CG cells in the chondral layer, with OS cells in the subchondral layer, did not augment tissue repair as influenced by the latter when compared to the control. Instead, CG7/OS implants resulted in more irregular neo-tissue surfaces when compared to MSC/OS implants. Notably, the delivery of CG7 cells, when compared to CG14 cells, with OS cells stimulated morphologically superior cartilage repair. However, neither osteogenic nor chondrogenic pre-differentiation affected detectable changes in subchondral tissue repair. CONCLUSIONS: Cartilage regeneration in osteochondral defects can be enhanced by MSCs that are chondrogenically and osteogenically pre-differentiated prior to implantation. Longer chondrogenic pre-differentiation periods, however, lead to diminished cartilage repair.

Background The goat is one of the most commonly used preclinical models for focal defect repair and regeneration. While the biomechanics of the human knee has been studied extensively, less is known about the biomechanics of the caprine knee. Differences between human and caprine knees have not been quantified and their significance is largely unknown. Methods We conducted a biomechanical analysis of the differences in goat and human knees to assess the validity of these preclinical in vivo models. Results CT and MRI scans revealed several differences in articular geometry: the caprine tibial plateaux were more convex and the menisci were significantly thicker and covered a larger proportion of the tibial articular surface. Caprine cartilage thickness was consistently thinner, while elastic modulus on indentation testing was consistently stiffer than human cartilage measured at eight different articular locations. Contact area and pressure were measured with electronic pressure sensors under loads normalized by multiples of body weight and at knee flexion angles reported for walking. The highest peaks in contact pressure were measured in the patellofemoral joint in goat and human knees. Peak contact pressure measured at 2 times body weight at the goat tibiofemoral joint at 70° flexion was significantly higher than for any other condition at the human tibiofemoral joint. Conclusion These differences in contact conditions might explain the lower quality of local repair reported for caprine femoral condylar defects relative to trochlear defects. Further comparative analysis, including biologic response, is necessary to determine the extent to which the goat knee reproduces clinical conditions.

Objective: The objective of this study was to assess the effect of granulocyte colony-stimulating factor (G-CSF) on osteochondral defect repair in the rat knee. Design: Twenty-six 12-week-old male Lewis rats were randomly divided into 2 groups. From day 0 to day 4, the G-CSF group received glycosylated G-CSF, and the control group received phosphate-buffered saline. A 1.5-mm diameter and 1.0-mm deep osteochondral defect was introduced in the patellar groove of the bilateral femur in all rats on day 4. The peripheral blood nucleated cells were counted for 14 days from the first day of injection, the appearance of the cartilage repair was observed histologically and macroscopically for 2, 4, 8, 12, and 24 weeks after surgery. Results: The number of peripheral blood leukocytes increased 3 days and returned to normal levels 7 days after the first injection. Compared with the control group, the G-CSF group had more fibrous and/or bony tissue at earlier points in time. The tissue repair rate, which is defined as the percentage of repaired osteochondral defects, was significantly higher in the G-CSF group 4 weeks after surgery. However, there were no significant differences in the cartilage repair rate and the modified Wakitani score between the 2 groups at each time point. Conclusions: The defect filling was significantly better in the G-CSF group in the early phases. Our findings suggest that G-CSF may promote the repair of osteochondral defects by mediating an increase in the number of peripheral blood nucleated cells.

Large composite soft tissue defects can be challenging to reconstruct especially whenever vital structures are exposed that would require large amount of healthy vascularized tissues for coverage. Whenever local or regional options for coverage are limited, free flaps are considered the preferred choice suitable for defect repair.

Congenitally corrected transposition of the great arteries is commonly associated with left ventricular outflow tract obstruction. We describe a case of congenitally corrected transposition of the great arteries and previous surgical ventricular septal defect repair with recurrent left ventricular outflow tract obstruction. The patient underwent a hybrid procedure to stent the left ventricular outflow tract, which was successful with no re-intervention through 3 years of follow-up.

Reconstructing functional volumetric tissue in vivo following implantation remains a critical challenge facing cell-based approaches. Several pre-vascularization approaches have been developed to increase cell viability following implantation. Structural and functional restoration was achieved in a preclinical rodent tissue defect; however, the approach used in this model fails to repair larger (>mm) defects as observed in a clinical setting. We propose an effective cell delivery system utilizing appropriate vascularization at the site of cell implantation that results in volumetric and functional tissue reconstruction. Our method of multiple cell injections in a progressive manner yielded improved cell survival and formed volumetric muscle tissues in an ectopic muscle site. In addition, this strategy supported the reconstruction of functional skeletal muscle tissue in a rodent volumetric muscle loss injury model. Results from our study suggest that our method may be used to repair volumetric tissue defects by overcoming diffusion limitations and facilitating adequate vascularization.