Acellular Research Articles

Does "Low-Grade" Dedifferentiated Liposarcoma Exist? The Role of Mitotic Index in Separating Dedifferentiated Liposarcoma From Cellular Well-differentiated Liposarcoma.

Subjective, varying criteria identify "low-grade" dedifferentiation in well-differentiated/dedifferentiated liposarcoma (WD/DDLPS). The value of mitotic rate (MR) in defining DDLPS is not confirmed. We studied all patients with the resection of their primary or first recurrence retroperitoneal WD/DDLPS at our institution to determine the value of MR in diagnosing DDLPS and if MR associates with patient survival. Ninety-eight patients with retroperitoneal WD/DDLPS operated at our institution from January 1, 1989 to December 31, 2013 were included. Cases were defined as acellular (AC) WDLPS, LS0-4 (tumors with non-lipogenic areas and MR 0-4/10HPFs) or LS5+(non-lipogenic areas, MR≥5/10 HPFs) and graded using the French system. Kaplan-Meier survival estimates with log-rank test and multivariate Cox (mCox) analyses were performed. Follow-up was available on all patients (median 9.3y, range 0.02-23.16y). Kaplan-Meier demonstrated a significant ( P =0.004) difference in disease-specific survival (DSS) among the 3 groups. mCox demonstrated no difference in DSS between the AC and LS0-4 groups (HR 1.51; 95% CI 0.57-3.99, P =0.412) but significantly lower DSS in the LS5+group compared with the AC group (HR 2.68; 95% CI 1.07-6.71, P =0.035). The difference in DSS was not significant between grade 2 and 3 tumors ( P =0.094). DSS between MR 5-19/10 HPFs and MR20+/10 HPFs subgroups was significant ( P =0.007) but by mCox did not reach significance (HR 2.47; 95% CI 0.96-6.35, P =0.060). This study confirms that MR distinguishes DDLPS from WDLPS with non-lipogenic areas, also known as cellular WDLPS. For consistency in diagnosis and research, only WD/DDLPS with≥5 mitoses/10 HPFs should be considered DDLPS.

Point-of-care treatment of geometrically complex midfacial critical-sized bone defects with 3D-Printed scaffolds and autologous stromal vascular fraction

Critical-sized midfacial bone defects present a unique clinical challenge due to their complex three-dimensional shapes and intimate associations with sensory organs. To address this challenge, a point-of-care treatment strategy for functional, long-term regeneration of 2 cm full-thickness segmental defects in the zygomatic arches of Yucatan minipigs is evaluated. A digital workflow is used to 3D-print anatomically precise, porous, biodegradable scaffolds from clinical-grade poly-ε-caprolactone and decellularized bone composites. The autologous stromal vascular fraction of cells (SVF) is isolated from adipose tissue extracts and infused into the scaffolds that are implanted into the zygomatic ostectomies. Bone regeneration is assessed up to 52 weeks post-operatively in acellular (AC) and SVF groups (BV/DV = 0.64 ± 0.10 and 0.65 ± 0.10 respectively). In both treated groups, bone grows from the adjacent tissues and restores the native anatomy. Significantly higher torque is required to fracture the bone-scaffold interface in the SVF (7.11 ± 2.31 N m) compared to AC groups (2.83 ± 0.23 N m). Three-dimensional microcomputed tomography analysis reveals two distinct regenerative patterns: osteoconduction along the periphery of scaffolds to form dense lamellar bone and small islands of woven bone deposits growing along the struts in the scaffold interior. Overall, this study validates the efficacy of using 3D-printed bioactive scaffolds with autologous SVF to restore geometrically complex midfacial bone defects of clinically relevant sizes while also highlighting remaining challenges to be addressed prior to clinical translation.

Seroma Formation in Pre-pectoral Implant-Based ADM Assisted Breast Reconstruction: A Comprehensive Review of Current Literature.

In the field of implant-based breast reconstruction (IBBR), the most recent and successful progress has been the evolution of the prepectoral approach through the use of acellular dermal matrix (ADM). ADM-assisted breast reconstruction is now gaining a foothold as standard practice, but its advantages are often clouded due to discouraging studies reporting increased seroma formation. The origin of the serum accumulation still remains unclear, but it has always been the most frequent early complication in breast reconstruction, thus proving to be crucial to address since it can lead to further complications. Using a standardized approach to obtain high-quality scientific evidence, the aim of this review is therefore to investigate the occurrence of seroma in breast implant-based reconstructive surgery and its possible relation with matrices. We conducted the review investigating only pre-pectoral implant positioning and one specific ADM (BraxonÃÂî) which is the one who has the highest number of cases in literature. nterestingly, ADM does not appear to be causative of seroma formation, but a surgery-related origin is discussed. In this setting, a series of rigorous guidelines have therefore been identified and analyzed to allow not only the treatment, but also the prevention of seroma, thus leading to a reduction in the incidence of this frequent problem.

More Reassurance That Vaccination During Pregnancy Is Not Linked to Stillbirth

Despite recommendations for universal immunization against influenza and tetanus, diphtheria, and acellular pertussis (Tdap) during each pregnancy,

National expert consensus on the application of natural dermal matrix in wound repair (2020 version)

Natural dermal matrix has good biocompatibility and can serve as " biological template" in wound repair. According to the source of material, natural dermal matrix can be divided into acellular dermal matrix (ADM), denatured dermal matrix, and scar dermal matrix. ADM is a biological material prepared by removing cellular components from the skin and retaining extracellular matrix (ECM) of the dermis. ADM possesses abundant natural biological information, low immunogenicity, and excellent regenerative capacity, which has greatly promoted the development of wound healing specialty as dermal substitute. Denatured dermis matrix is a layer of dermal tissue made by superficial tangential excision or dermabrasion on deeply burned wounds. The retained denatured dermis can recover gradually after transplantation of autologous skin on its surface, with similar structure, morphology, and biomechanics to healthy dermis. Scar dermal matrix is a kind of dermal scaffold made of autologous split-thickness scar tissue, possessing the characteristics of high survival rate, good texture, and slight scar reaction. Scar dermal matrix can effectively reduce secondary damage to the donor site when repairing scar contracture deformity. Based on the research progress at home and abroad and the opinions of domestic experts, this paper summarizes the indications, application methods, contraindications, and considerations of different types of natural dermal matrix in application of wound repair.

Acellular advantage

Acellular advantage

Use of ovine acellular peritoneal matrix combined with honey and ovine fetal skin extract in the healing of full-thickness infected burn wounds in a rat model.

Treatment of infected burn wounds remains a challenge in burn units. Silver-sulfadiazine (SSD) is the most commonly used topical antimicrobial agent in managing these wounds. We aimed to accelerate the healing of burn wounds by combined application of ovine acellular peritoneal matrix (OAPM), honey (H), and ovine fetal skin extract (OFSE). Sixty-four standardized burn wounds were created on the dorsum of 16 rats and were subsequently inoculated with Staphyloccocus aureus and Pseudomonas aeruginosa. After 48 hr, the wounds were surgically debrided and received either physiologic saline (control group) or SSD, OAPM+SSD, OAPM+H+SSD, and OAPM+H+OFSE+SSD. The healing wounds were evaluated for size, bacterial counts, histopathology, and biomechanical properties on days 3, 7, 14, 21, and 28 after surgery. All treatments had effectively reduced the level of S. aureus and P. aeruginosa on wounds compared to the control group by day 3 and 7. The wounds treated with combined application of OAPM+H+OFSE+SSD demonstrated considerable inflammation reduction, fibroplasia, complete re-epithelialization, and wound contraction together with significantly lesser scar tissue formation. Treatment with OAPM+H+OFSE+SSD showed superior biomechanical properties of the healing wounds. The findings suggested that the synergistic effect of dressing the wounds with OAPM, H, and OFSE was a very effective approach in accelerating the healing process of the experimentally induced infected full-thickness burn wounds in rats.

Genipin cross-linked decellularized scaffold for allogenic transplantation in situ

Objective To explored the bio-compatibility and cartilage regeneration of the rabbits genipin cross-linked decellularized scaffold, to provide experimental and theoretical support for the clinical application of genipin cross-linked decellularized scaffold. Methods Detergent-enzyme method was used to prepare decellularized tracheal scaffolds. Cellular content of native trachea and decellularized trachea were compared by 4′, 6-diamidino-2-phenylindole(DAPI) staining. Masson trichrome staining was used to compare the histological structure of the progenitor tube, decellularized trachea, and genipin cross-linked decellularized trachea. Nine adult New Zealand white rabbits were randomly divided into autologous tracheal transplantation group (negative control group), allogeneic tracheal transplantation group (positive control group), and genipin cross-linked decellularized tracheal transplantation group (experimental group). Autologous bone marrow mesenchymal stem cells were implanted on the surface of trachea in each group. The blood cells and type II collagen were detected to compare the inflammatory response and chondrocyte regeneration after tracheal orthotopic transplantation in the three groups. Results After DAPI staining and light microscope observation (×200), the cell content of the acellular 7-cycle trachea [(143.0 ± 71.1) cells/field] was significantly lower than that of the native trachea [(853.5 ± 149.6) cells/field], and the difference was statistically significant (P<0.001). Masson′s trichrome staining showed that the tissue structure of genipin cross-linked decellularized trachea was more complete. Blood cell analysis and type II collagen test results showed that genipin cross-linked decellularized trachea transplanted with bone marrow mesenchymal stem cells after transplantation in situ has little rejection and can be converted into chondrocytes by the action of related growth factors in vivo. Conclusions Genipin cross-linked decellularized tracheal scaffold combined with stem cell transplantation can successfully construct a tracheal in situ replacement model. This study provides a strong support for the research of tissue engineering trachea. Key words: Tissue engineering; Trachea; Transplantation; Genipin cross-linked; Mesenchymal stem cells

The study of wound surface thinning combined with acellular dermal matrix transplantation for severe burn wound sepsis

The study of wound surface thinning combined with acellular dermal matrix transplantation for severe burn wound sepsis

Application of yak pericardium in anti-calcification heart valves

Objective To explore the feasibility of the application of yak pericardium as anti-calcified heart valve materials in transcatheter aortic valve replacement (TAVR). Cattle pericardium and commercial Sino products were used as controls. Methods Yak and cattle pericardium was decellularized, and then the acellular extent was qualitatively and quantitatively analyzed with hematoxylin-eosin (HE) staining and DNA detection kit respectively. Two cross-linking agents, i.e. glutaraldehyde and genipin, were used to cross-link the acellular pericardium, respectively. After testing the mechanical property, thermodynamic stability and biocompatibility of the pericardium, the cross-linked pericardium was subcutaneously implanted in juvenile Wistar rats. After 2~4 weeks of the implantation, histological staining and tissue calcification analysis were conducted. Results The nuclei of the yak pericardium were almost invisible after decellularized treatment, and the DNA content decreased from (0.90±0.13) μg/mg to (0.09±0.02) μg/mg that was significantly lower than that of Sino product (P 0.05). For the two cross-linked yak pericardium, the hemolysis rate and cell proliferation ratio was similar with that of cattle pericardium (all P>0.05), the tissue regeneration ability of subcutaneous implantations was inferior, and the calcification level was higher than that of cattle pericardium with an no statistically significant difference (all P>0.05). After 4 weeks of the subcutaneously implantation, the calcium content of the glutaraldehyde cross-linked pericardium was 32.62~65.49 μg/mg. Conclusions Yak pericardium has better mechanical properties and thermodynamic stability than cattle pericardium, and the biocompatibility can meet the requirements of transcatheter aortic valve replacement. Key words: Heart valves; Yak pericardium; Acellular matrix; Crosslinking; Anti-calcification

Forty years (1978-2018) of vaccination policies in Italy.

Forty years (1978-2018) of vaccination policies in ItalyThe paper traces the evolution of vaccination policies in Italy in the first 40 years of the National Health Service. Four phases have been identified: the first (1978-98) characterized by the eradication of smallpox, the hopes of further eradications and the introduction of hepatitis B and acellular antipertussis vaccines; the second (1999-2008) coincided with the first national vaccination plans and with the hypothesis of a progressive transition from mandatory vaccinations to nudging initiatives with the relevant experimentation in the Veneto Region; the third phase (2009-14) was characterized by the spread of health information on the web and social networks, by anti-scientific judgments and by an increasingly vaccines hesitancy that led to incorrect perceptions, falls in coverage rates and re-ignition of some epidemics; in the last phase (2015-18) there was a strong political committment that led to the approval of the National Plan (PNPV) 2017-19, to the extension of the mandatory vaccinations and to the sanctions against the anti-vaxxers doctors. This has led to a rapid rise in coverage, but also to a heated political and media debate on the ethical and social aspects linked to the admission bans and sancions of unvaccinated children in schools. (www.actabiomedica.it)Riassunto. Il lavoro ripercorre l’evoluzione delle politiche vaccinali in Italia nei primi 40 anni del Servizio Sanitario Nazionale. Sono state identificate quattro fasi: la prima (1978-98) caratterizzata dall’eradicazione del vaiolo, dalle speranze di ulteriori eradicazioni e dall’introduzione dei vaccini antiepatite B e antipertosse acellulare; la seconda (1999-2008) è coincisa con i primi piani vaccinali nazionali e con l’ipotesi di un progressivo passaggio dall’obbligo all’adesione consapevole, segnata dall’importante sperimentazione della Regione Veneto; la terza fase (2009-14) è stata caratterizzata dalla diffusione dell’informazione sanitaria su web e social, da sentenze giudiziarie antiscientifiche e da una sempre più diffusa vaccine hesitancy che hanno portato a errate percezioni, cali generalizzati delle coperture e riaccensione di focolai epidemici; nell’ultima fase (2015-18) c’è stata una reazione delle istituzioni che ha portato all’approvazione del PNPV 2017-19, all’estensione degli obblighi vaccinali e a sanzioni contro i medici antivaccinisti. Ciò ha portato ad un rapido rialzo delle coperture ma anche ad un acceso dibattito politico e mediatico sugli aspetti etici e sociali legati alle sanzioni e ai divieti di ammissione dei bambini non vaccinati nelle scuole.

Clinical effects of pretarsal fullness reconstruction of the lower eyelid using autologous dermis or acellular dermis

Objective To investigate the new metheds of recreating pretarsal fullness of the lower eyelid using autologous dermis or acellullar dermis. Methods Between September 2010 and November 2013, total 16 patients underwent the procedures of recreating of pretarsal fullness of the lower eyelid using dermis materials. A stab skin incision of approximately 4-5 mm was made at the lateral canthus and inner canthus along the subciliary crease of the lower eyelid respectively, and then the skin was undermined to create a subcutaneous tunnel between two stab incisions. The dermis roll was introduced into the undermined subcutaneous plane of the lower eyelid. The end of dermis was sutured to orbicularis oculi muscle to maintain the appropriate tension. Results 11 cases of them used autologous dermis, 5 of used acellullar dermis. The patients were followed up for 3-24 months. Lower-eyelid pretarsal fullness regained abvious and natural appearance, and the patients were highly satisfied. Complications included slight sclera show, partial absorption of dermis material and slight irregular apperence. One case of dermis infection occured and dermis roll had to be removed. Conclusions Autologous dermis or acellullar dermis grafting are simple, efficient techniques for recreating of pretarsal fullness of the lower eyelid. Key words: Transplantation, autologous; Dermis; Acellular dermis; Minor surgical procedures; Pretarsal fullness

Narrowing Down the Best Tdap Window During Pregnancy

To protect newborns against pertussis, maternal immunization with tetanus, diphtheria, and acellular pertussis (Tdap) vaccine is recommended during the

Effect of the use of acellular nerve allograft through chemical extraction in repair of rat sciatic nerve defect on survival rate of motor neurons in spinal cord

Effect of the use of acellular nerve allograft through chemical extraction in repair of rat sciatic nerve defect on survival rate of motor neurons in spinal cord

Establishment of mouse neutralizing antibody detection method as potency assay for acellular pertussis vaccines

Objective To establish a functional antibody detection method for acellular pertussis vaccines in order to conveniently and effectively evaluate the production consistency and potency of acellular pertussis vaccine bulks and final products. Methods Chinese hamster ovary (CHO) cell clustering assay was optimized and used to measure titers of neutralizing antibodies against pertussis toxin in mouse immune serum samples. Results Vaccine samples were determined to be immunized intraperitoneally with 1/5 the human dose to ten female NIH mice (20-24 g, 5-week-old). Four weeks after immunization, blood samples were collected to isolate serum. Serially diluted serum samples were used to neutralize 0.1 IU/ml of pertussis toxin national reference product for 2 hours. Results of clustering were determined after 48 hours of incubation in pre-cultured CHO cell wells. The geometric mean of the serum dilution of the final unclustered wells was the neutralizing antibody titer of vaccine sample. There were significant differences in the titers of neutralizing antibodies elicited by acellular pertussis vaccines prepared with different manufacturing processes. Vaccine samples succeed or failed the modified intracerebral challenge assay (MICA) were easily distinguishable by neutralizing antibodies. Conclusion The method of detecting neutralizing antibodies to pertussis toxin greatly reduces the amount of animals used in research. CHO cell clustering assay that has better repeatability and precision can be used for monitoring and initial evaluation of the consistency and potency of the bulks and final products of pertussis vaccines prepared with different manufacturing processes. Key words: Pertussis toxin; Acellular pertussis vaccine; Neutralizing antibody; CHO cell; Potency assay

Observation of the efficacy of biological patch in hybrid technique for incisional herniorrhaphy: 5-year follow-up results from a single center

To observe the safety and efficacy of biological patch (Biodesign Surgisis mesh, SIS) in hybrid technique for incisional herniorrhaphy. Clinical and follow-up data of 14 incisional hernia patients who underwent incisional herniorrhaphy with hybrid technique, using porcine small intestinal submucosa acellular matrix patch, at the First Affiliated Hospital of Sun Yat-sen University from January 1, 2012 to June 31, 2016 were analyzed retrospectively. This Biodesign Surgisis patch for incisional hernia is produced by the Cook company in the United States. The size of patch ranged from 9 cm × 15 cm to 20 cm × 25 cm. During operation, according to abdominal wall defect, the patch was cut to ensure the distance from its edge to the border of abdominal wall defect more than 5 cm. There were four male and tenfemale patients with average age of (67.7±11.6) years and average body mass index(BMI) of (25.5±1.7) kg/m². As for operative history of these 14 cases, 7 cases had gastrointestinal tumor surgery, 2 had appendectomy, 1 had upper abdominal white line hernia repair, 1 had hysterectomy, 1 had cholecystectomy, 1 had splenectomy plus portal vein dissection, and 1 had right kidney and right ureter total resection plus partial excision of bladder wall. Ten casesdeveloped incisional infection after previous surgery. The duration of incisional hernia ranged 1 to 180 months (median, 8 months). Two cases were refractory hernia, 1 was incarcerated hernia, and 11 were reversible hernia. The locations of incisional hernia included 4 cases of right ventral wall, 1 case of left ventral wall, 2 cases of supra-umbilical incision, 4 cases of infra-umbilical midline incision, and 3 cases of peri-umbilical midline incision. There were 3 cases of middle incisional hernia, 5 cases of large incisional hernia and 6 cases of huge incisional hernia. All the patients completed operations eventlessly. The average operative time was (202.5±72.9) minutes. The average length and width of hernia ring were (10.9±4.3) cm and (9.3±3.9) cm, respectively. Clean operation was performed in 11 cases, potential contaminative operation in 2 cases and contaminative operation in 1 case. The amount of operative bleeding was (15.0±4.8) ml. The NRS pain scores within 24 hours after the operation, at POD3 and at POD7 were 5.1±0.9, 4.2±0.7 and 3.7±0.9, respectively. The time to flatus after operation was (2.5±0.9) days and the time to liquid diet was (3.8±1.2) days. No patient died during the perioperative period. The average hospitalization time was (21.5±12.0) days. Postoperative complications occurred in 8 cases, including 4 cases of fever, 8 cases of incision complications, 4 cases of abdominal infection, 4 cases of intestinal obstruction, 5 cases of effusion under patch, 2 cases of pneumonia, and 1 case of acute myocardial infarction. According to the Clavien-Dindo classification, 3 cases were grade zero, 3 cases were grade I(, 6 cases were grade II(, 1 case was grade III(, and 1 case was grade IIII(. Thirteen patients received follow-up and the average follow-up time was (33.2±12.3) (18.2-61.0) months. One patient died of cerebral infarction 38 months after operation. The chronic abdominal pain or discomfort was found in 4 cases. The recurrent incisional hernia developed in 5 cases and the average time of recurrence was (11.0±8.3) months. Biological patch can be used safely and effectively in hybrid technique for incisional herniorrhaphy. However, the morbidity of postoperative complication and the risk of recurrence are high. Terefore, the long-term outcome is still subject to observation.

Hundred years development and future prospect of the material science for hernia

Inguinal hernia is a defect disease in the abdominal wall. Surgeons have tried various ways to repair the defect for more than 100 years. The traditional herniorrhaphy destroys the normal anatomical structure, and the recurrence rate is quite high. After that, surgeons began to repair the defects with prostheses, from the initial use of rough metal materials such as silver, tantalum, stainless steel, to nylon, fiberglass, silicone rubber and other non-metallic materials, and also from artificial synthetic polymer non-absorbable materials such as polypropylene, polyester, ePTFE, to synthetic absorbable materials such as polyglycolic acid and the acellular extracellular matrix derived from biological meshes. However, these prostheses still can not meet the diverse needs of patients. Thus, multifunctional composite prostheses consisting of two or more materials were born, and various types of composite prostheses, stem cell coating meshes, 3D meshes, microstructure meshes were developed. The repair method evolved from traditional hernia repair to tension-free hernia repair and laparoscopic hernia repair. Surgeons are dedicated to finding idealized meshes for the perfect repair of defects, while considering postoperative complications, patient's quality of life, long-term efficacy and other issues. In the face of a wide variety of repair materials, the choice of surgeons is blind, and there is no standard to determine which prostheses are suitable for patients. Therefore, we have combed the development of different types of prostheses, summarized the development process of hernia repair materials for the past 100 years, and put forward the prospects for future development of prostheses, in order to provide reference for the selection of prostheses.

Corrigendum to "Evaluation of Complication Rates after Breast Surgery Using Acellular Dermal Matrix: Median Follow-Up of Three Years".

[This corrects the article DOI: 10.1155/2017/1283735.].

Diphtheria, Tetanus, and Acellular Pertussis Vaccine Is Safe

The current pertussis vaccine for children aged 2 months to 7 years, diphtheria, tetanus, and acellular pertussis (DTaP), was introduced in the 1990s

Experimental studies on the repair and restitution of cartilage cartilage by cartilage acellular extracellular matrix and adipose tissue-derived stem cells

Experimental studies on the repair and restitution of cartilage cartilage by cartilage acellular extracellular matrix and adipose tissue-derived stem cells