Airway reconstruction using decellularized aortic xenografts in a dog model.

Tracheal reconstruction after extensive resection remains a challenge in thoracic surgery. Aortic allograft has been proposed to be a potential tracheal substitute. However, clinically, its application is limited for the shortage of autologous aortic segment. Whether xenogeneic aortic biosheets can be used as tracheal substitutes remains unknown. In the present study, we investigated the possibility in dog model. The results show that all dogs were survived without airway symptoms at 6 months after tracheal reconstruction with gently decellularized bovine carotid arteries. In the interior of engrafted areas, grafted patch integrated tightly with the residual native tracheal tissues and tracheal defects in the lumen were repaired smoothly without obvious inflammation, granulation, anastomotic leakage, or stenosis. In addition, histological and scanning electron microscopy examination showed that grafted patches were covered with ciliated columnar epithelium similar to epithelium in native trachea, which indicated successfully re-epithelialization of decellularized bovine carotid arteries in dogs. These findings provide preclinical investigation of xenogeneic aortic biosheets in serving as tracheal substitute in a dog model, which proposes that decellularized biosheets of bovine carotid may be a potential material for bioartificial tracheal graft.

Comparação entre dois tipos de enxertos (Mucograft® e Mucoderm®) associados ao retalho posicionado coronariamente no tratamento de recessões gengivais unitárias: estudo clínico controlado randomizado / Comparison of two types of grafts (Mucograft® and Mucoderm®) associated with coronally advanced flap in the treatment of single gingival recessions: randomized clinical trial

A recessão gengival está frequentemente associada à hipersensibilidade dentinária e insatisfações estéticas. Diversas técnicas cirúrgicas foram desenvolvidas a fim de reestabelecer a posição da margem gengival acometida. Dentre elas, a adição de biomateriais aos procedimentos cirúrgicos de retalho posicionado coronariamente (CAF) é considerada uma alternativa promissora. O objetivo do presente estudo foi comparar os efeitos do uso de dois enxertos, matriz colágena (CM, Mucograft®) e matriz dérmica acelular xenógena (XDM, Mucoderm®), no tratamento de recessões gengivais unitárias associados ao CAF. Para tal, 75 pacientes portadores de recessões gengivais unitárias foram selecionados e divididos em três grupos: CAF (n=25, técnica isolada de CAF para recobrimento radicular), CAF+CM (n=25, CAF associado à CM) e CAF+XDM (n=25, CAF associado à XDM). Os parâmetros clínicos e centrados no paciente foram avaliados no baseline e seis meses após o tratamento. Aos seis meses, os três grupos apresentaram porcentagens significativas de recobrimento radicular (78,9±26,2% para CAF, 78,0±28,5% para CAF+CM e 65,6±26,9% para CAF+XDM), sem diferença significativa entre os grupos (p>0,05). O recobrimento radicular completo foi obtido em 52%, 48% e 28% dos casos tratados com CAF, CAF+CM e CAF+XDM, respectivamente (p=0,2). Os grupos que receberam enxerto apresentaram maior ganho de espessura de tecido queratinizado (ETQ; p<0,001). Não foram observadas diferenças no grau de edema tecidual (p=0,9) e desconforto pós-operatório (p=0,2) aos sete dias. Todos os grupos apresentaram redução significativa da hipersensibilidade dentinária (p<0,001) e melhora nas condições de estética (p<0,05), sem diferença significativa entre os grupos (p>0,8). Não houve diferença intergrupo em relação ao tempo cirúrgico (p=0,07). Dentro das limitações desse estudo, concluiu-se que os três tratamentos foram eficazes e que a adição de CM e XDM não promoveu benefícios adicionais ao CAF em termos de recobrimento radicular. Entretanto, a adição dos enxertos parece contribuir para o aumento da espessura de tecido queratinizado(AU)

Gingival recession is frequently associated with dentin hypersensitivity and aesthetic complaint. Different periodontal surgical techniques have been developed in order to reestablish the position of the gingival margin. The addition of biomaterials to coronally advanced flap (CAF) surgical procedures is considered a promising alternative. The aim of this study was to compare the effects of using two biomaterials, collagen matrix (CM, Mucograft®) and xenogeneic acellular dermal matrix (XDM, Mucoderm®) associated with CAF technique for the treatment of single gingival recessions. For this, 75 patients presenting single gingival recessions were selected and allocated into three groups: CAF (n=25, CAF for root coverage alone), CAF+CM (n=25, CAF associated with CM) and CAF+XDM (n=25, CAF associated with XDM). Clinical and patient-centered parameters were assessed at baseline and six months post-procedures. At six months, the groups had significant percentages of root coverage (78.9±26.2% for CAF, 78.0±28.5% for CAF+CM e 65.6±26.9% for CAF+XDM), with no intergroup difference. Complete root coverage was obtained in 52%, 48% and 28% of cases treated with CAF, CAF+CM and CAF+XDM, respectively (p=0.2). The groups which received some graft showed greater gain in keratinized tissue thickness (p<0,001).No differences were observed in tissue edema (p=0.9) and postoperative discomfort (p=0.2) at seven days. All groups showed significant dentin hypersensitivity reduction (p<0.001) and improvements in aesthetic conditions (p<0.05), with no significant difference between groups (p>0.8). There was no intergroup difference for surgical time (p=0.07). Within the limitations of this study, it was concluded that all treatments were effective and the use of CM and XDM did not promoted additional benefits to CAF in terms of root coverage. However, the addition of grafts seems to contribute to the increase of keratinized tissue thickness(AU)

Replacement of infected aortoiliac vascular grafts with bifurcated BioIntegral Surgical No-React® bovine pericardial xenografts.

The infection of a vascular prosthesis is potentially fatal, and its effective treatment still remains the greatest challenge for vascular surgeons. We present our initial experience using bovine pericardial vascular prostheses to replace infected aortoiliac vascular grafts. Six consecutive patients with infection of the graft were prospectively included in this study. Infection of the vascular graft was confirmed by clinical symptoms, laboratory tests and the results of computed tomography and positron emission tomography/computed tomography. In all cases, the infected aortoiliac graft was surgically removed and replaced by the bovine-pericardial BioIntegral aortic-bifemoral prosthesis. Technical success was achieved in every case with no in-hospital or 30 days mortality. One patient required revision of distal anastomosis due to recurrent bleeding at day four after surgery. One patient presented with upper gastrointestinal tract bleeding during the postoperative period, which was managed endoscopically. The mean hospital stay was 14 days (range 9-19). The control CT scan performed 2 months after surgery showed significant regression of abscesses and periprosthetic inflammation. Two patients died within 32 months of follow-up: one due to heart attack, the other due to generalized sepsis, which was correlated with the previous infection. Four patients are still in follow-up. The BioIntegral prosthesis is patent in all four cases, with no clinical or ultrasonographic signs of infection. Our brief investigation shows that a bovine pericardial prosthesis may be a valuable option in the treatment of vascular grafts infections.

Transplantation of Human Intestine Into the Mouse: A Novel Platform for Study of Inflammatory Enterocutaneous Fistulas.

BACKGROUND AND AIMS: Enteric fistulas represent a severe and medically challenging comorbidity commonly affecting Crohn's disease [CD] patients. Gut fistulas do not develop in animal models of the disease. We have used transplantation of the human fetal gut into mice as a novel platform for studying inflammatory enterocutaneous fistulas. METHODS: Human fetal gut segments were transplanted subcutaneously into mature SCID mice, where they grew and fully developed over the course of several months. We first analysed the resident immune cells and inflammatory response elicited by systemic lipopolysaccharide [LPS] in normal, fully developed human gut xenografts. Thereafter, we used immunostaining to analyse fully developed xenografts that spontaneously developed enterocutaneous fistulas. RESULTS: Resident human innate and adaptive immune cells were demonstrated in gut xenografts during steady state and inflammation. The expression of human IL-8, IL-1ß, IL-6, TNF-α, A20, and IkBα was significantly elevated in response to LPS, with no change in IL-10 gene expression. Approximately 17% [19/110] of fully developed subcutaneous human gut xenografts spontaneously developed enterocutaneous fistulas, revealing striking histopathological similarities with CD fistula specimens. Immunohistochemical analyses of fistulating xenografts revealed transmural lymphocytic enteritis associated with massive expansion of resident human CD4+ lymphocytes and their migration into the intraepithelial compartment. Regionally, mucosal epithelial cells assumed spindle-shaped mesenchymal morphology and formed fistulous tracts towards chronic non-healing wounds in the host mouse skin overlying the transplants. CONCLUSIONS: Inflammation and fistulas developed in human gut xenografts lacking IL-10 gene response. This novel model system will enable systematic studies of the inflamed and fistulating human gut in live animals.

Eroded Tape: A Case of an Early Vesicoscopy Rather Than Laser Melting.

OBJECTIVE: To report our experience on vesicoscopic excision of eroded foreign material in the bladder. MATERIALS AND METHODS: The use of xenografts in female urology is becoming more prevalent and so are their complications. Erosion of foreign material into the bladder often goes unrecognized for a long time and patients are troubled by irritative urinary symptoms, recurrent infections, and stone formation. The treatment of such erosions is traditionally reported through the transurethral route using laser or electrocautery to cut the foreign material. Such methods have a high rate of incomplete material removal and as a result a high recurrence rate. Leaving a urothelial defect results in prolonged time to symptom resolution. Between 2012 and 2015, 5 patients with eroded tapes were referred for tertiary care to King's College Hospital and Ygia Polyclinic; all patients had undergone a variety of endoscopic, vaginal, and/or open attempts for mesh removal that failed. We offered vesicoscopic excision of the eroded portion of the tape. RESULTS: We here report 5 cases with tape erosions referred to our team that were treated with vesicoscopic excision of the material and primary closure of the urothelial defect. The foreign material was completely removed in all cases and there is no recurrence at a median follow-up of 30 months. CONCLUSION: Vesicoscopic excision of bladder-eroded foreign material is feasible and efficient. We recommend this technique to be considered as a primary approach to tapes eroding into the bladder.

Successful Xenograft of Endoscopic Ultrasound-Guided Fine-Needle Aspiration Specimen from Human Extrahepatic Cholangiocarcinoma into an Immunodeficient Mouse.

Patient-derived tumor xenograft is the transfer of primary human tumors directly into an immunodeficient mouse. Patient-derived tumor xenograft plays an important role in the development and evaluation of new chemotherapeutic agents. We succeeded in generating a patient-derived tumor xenograft of a biliary tumor obtained by endoscopic ultrasound-guided fine-needle aspiration from a patient who had an inoperable extrahepatic cholangiocarcinoma. This patient-derived tumor xenograft will be a promising tool for individualized cancer therapy and can be used in developing new chemotherapeutic agents for the treatment of biliary cancer in the future.

Maxillary Sinus Augmentation with a New Xenograft: A Randomized Controlled Clinical Trial.

BACKGROUND: Insufficient residual alveolar bone height is a common deterrent in the placement of dental implants in the posterior maxilla. The use of autografts, xenografts, allografts and alloplasts or a combination between them has been demonstrated to be effective for increasing bone height and bone volume in the deficient posterior maxilla. PURPOSE: The aim of this clinical trial is to comparatively determine the density of newly formed in sinus floor augmentation bone after a 24-week healing period treatment with a new bovine xenograft. MATERIALS AND METHODS: The sinus floor was grafted with Bio-Oss® (n = 10) and Osseous® (n = 10). Histological sections were examined with a focus on the presence of connective tissue (CT) and newly formed bone (NFB). The sections were histomorphometrically evaluated and the definitive crown was inserted after 3 months. RESULTS: After 6 months, the mean value of new bone formation was 24.60 (±2.503), the CT was 42.60 (±4.006) and the remaining biomaterial was 25.40 (±2.547) in Bio-Oss group. In Osseous group, the mean value of new bone formation was 24.90 (±3.542), the CT was 45.70 (±7.040) and the remaining biomaterial was 22.90 (±3.247). CONCLUSIONS: Both biomaterials afforded a favorable implant position and the prosthetic rehabilitation.

Prosthetic heart valves.

Heart valve replacements improve symptoms and life expectancy but may have potential problems. Biological replacements have limited durability but do not require anticoagulation and are usually used for the relatively elderly. Mechanical valves have a virtually zero primary failure rate but require anticoagulation and are usually used for the relatively younger patient. Transcatheter valves are used for patients in whom conventional surgery is not technically feasible or who have significant comorbidities. This article discusses the management of patients after valve replacement and discusses future developments.