Lyophilized Porcine Dermis Research Articles

Treatment for rectourethral fistulas after radical prostatectomy with biological material interposition through a perineal access

IntroductionRectal injury is a rare complication after extraperitoneal laparoscopic radical prostatectomy. The development of rectourethral fistulas (URF) from rectal injuries is one of the most feared and of more complex resolution in urology. Material and methodsBetween 2013 and 2020 we have operated on a total of 5 patients with URF after extraperitoneal endoscopic radical prostatectomy through a perineal access using the interposition of biological material. All fistulas had a diameter of less than 6 mm at endoscopy and were less than 6 cm apart from the anal margin. ResultsThe mean age of the patients was 64 years old. All patients had a previous bowel and urinary diversion for at least 3 months. Under general anesthesia and with the patient in a forced lithotomy position, fistulorraphy and interposition of biological material of porcine origin (lyophilized porcine dermis [Permacol®]) were performed through a perineal access. Mean operative time was 174 min (140–210). Most patients were discharged on the third postoperative day. The bladder catheter was left in place for a mean of 40 days (30–60). Prior to its removal, cystography and a Gastrografin® barium enema were performed, showing resolution of the fistula in all cases. ConclusionsThe interposition of biological material from porcine dermis through perineal approach is a safe alternative with good results in patients submitted to urethrorectal fistulorraphy after radical prostatectomy.

Tratamiento de las fístulas uretrorrectales tras prostatectomía radical mediante la interposición de material biológico vía perineal

IntroductionRectal injury is a rare complication after extraperitoneal laparoscopic radical prostatectomy. The development of rectourethral fistulas (URF) from rectal injuries is one of the most feared and of more complex resolution in urology. Material and methodsBetween 2013 and 2020 we have operated on a total of 5 patients with URF after extraperitoneal endoscopic radical prostatectomy through a perineal access using the interposition of biological material. All fistulas had a diameter of less than 6 mm at endoscopy and were less than 6 cm apart from the anal margin. ResultsThe mean age of the patients was 64 years old. All patients had a previous bowel and urinary diversion for at least 3 months. Under general anesthesia and with the patient in a forced lithotomy position, fistulorraphy and interposition of biological material of porcine origin (lyophilized porcine dermis [Permacol®]) were performed through a perineal access. Mean operative time was 174 minutes (140-210). Most patients were discharged on the third postoperative day. The bladder catheter was left in place for a mean of 40 days (30-60). Prior to its removal, cystography and a Gastrografin® barium enema were performed, showing resolution of the fistula in all cases. ConclusionsThe interposition of biological material from porcine dermis through perineal approach is a safe alternative with good results in patients submitted to urethrorectal fistulorraphy after radical prostatectomy.

Promotive Effects of a Silk Film on Epidermal Recovery from Full‐Thickness Skin Wounds

Abstract. We examined the effects of the transparent fibroin film (silk film) on full‐thickness skin wounds. Full‐thickness dermatotomies (15 mm × 9 mm) were prepared on the dorsal wall of CRJ:CD‐1 nu/nu (ICR nu/nu) mice. The area of the wounds dressed with silk film was reduced to 10% of that made by the dermatotomy 14 days after the dermatotomy and were covered with regenerated epidermis 21 days after the dermatotomy. In contrast, less recovery and epidermal regeneration were found 14 days after dermatotomy in the wounds dressed with a conventional hydrocolloid dressing (Duro Active). Furthermore, only partial incomplete epidemal growth was obtained 21 days after dermatotomy. Most importantly, the healing time of wounds dressed with silk film was 7 days shorter than those dressed with DuoActive dressing. The silk film showed an almost similar or slightly better promotive effect as the lyophilized porcine dermis (Alloask D), which is used as a dressing for burns, ulcers, and decubitis. Histologic findings revealed that there was greater collagen regeneration and less inflammation and neutrophil‐lymphocyte infiltration of the wounds dressed with silk film than with DuoActive dressing. It is clear that regeneration of the epidermis and dermis of the wound beds covered with silk film was faster than with DuoActive dressing. Finally, silk film is easily obtainable, sterilizable, and transparent, and it allows easy observation of tissue recovery. Therefore, silk film offers advantages over other dressings and may be clinically useful for wound treatment.

Promotive effects of a silk film on epidermal recovery from full-thickness skin wounds.

We examined the effects of the transparent fibroin film (silk film) on full-thickness skin wounds. Full-thickness dermatotomies (15 mm x 9 mm) were prepared on the dorsal wall of CRJ:CD-1 nu/nu (ICR nu/nu) mice. The area of the wounds dressed with silk film was reduced to 10% of that made by the dermatotomy 14 days after the dermatotomy and were covered with regenerated epidermis 21 days after the dermatotomy. In contrast, less recovery and epidermal regeneration were found 14 days after dermatotomy in the wounds dressed with a conventional hydrocolloid dressing (Duro Active). Furthermore, only partial incomplete epidemal growth was obtained 21 days after dermatotomy. Most importantly, the healing time of wounds dressed with silk film was 7 days shorter than those dressed with DuoActive dressing. The silk film showed an almost similar or slightly better promotive effect as the lyophilized porcine dermis (Alloask D), which is used as a dressing for burns, ulcers, and decubitis. Histologic findings revealed that there was greater collagen regeneration and less inflammation and neutrophil-lymphocyte infiltration of the wounds dressed with silk film than with DuoActive dressing. It is clear that regeneration of the epidermis and dermis of the wound beds covered with silk film was faster than with DuoActive dressing. Finally, silk film is easily obtainable, sterilizable, and transparent, and it allows easy observation of tissue recovery. Therefore, silk film offers advantages over other dressings and may be clinically useful for wound treatment.

Ｉｎ ｖｉｔｒｏにおけるキチンのフィブロネクチンおよび線維芽細胞遊走因子の産生誘導におよぼす影響

Chitin has been used as a temporary dressing material for dermal wounds. The properties of chitin for wound repair include hemostatic, analgesic, wound drying, and wound-healing accelerating effects. However, few studies have reported the use of chitin in the oral cavity. In order to investigate the mechanisms of these favorable properties, the influence of chitin on the oral tissue was analyzed as described below. In this study, chitin was tested for its capacity to induce fibronectin production and human gingival fibroblast-like cell (HGF) migration from human peripheral monocytes, and compared with lyophilized porcine dermis (LPDS) and collagen wound dressing (CAS). Fibronectin and HGF chemotactic activity in the supernatants of HGF (FCM) cultured on chitin, LPDS and CAS were examined. Furthermore, macrophage conditioned medium (MCM) was added to HGF culture on each wound dressing material, and the supernatants were examined in a similar manner. Fibronectin production by macrophages was highest when the cells were cultured on LPDS. On the other hand, when MCM was added to the HGF culture on chitin, fibronectin production was strongly induced. When all supernatants were cultured on chitin, HGF chemotaxis was more active than any other material.

キチンの線維芽細胞増殖および上皮成長因子産生に及ぼす影響

Chitin has been used as a temporay dressing material for dermal wounds. The properties of chitin for wound repair include hemostatic, analgesic, wound drying, and wound-healing accelerating effects. Furtheremore, it has been suggested that wounds treated with chitin have minimal scar formation after healing. However, there have been few studies of the use of chitin in the oral mucosa. In order to investigate the mechanisms of these favorable properties, the influence of chitin on the healing of oral tissue wounds was analyzed as described below. In this study, human gingival fibroblast-like cells (HGF) and macrophages cultured on chitin and other materials, such as lyophilized porcine dermis (LPDS) and collagen wound dressing (CAS), were studied. The growth of human gingival fibroblast-like cells (HGF) and their capacity to induce fibroblast growth factor (FGF) production and, epidermal growth factor (EGF) production in the supernatants of human peripheral monocytes and HGF cultures were analyzed and compared with the results obtained for chitin. Furthermore, macrophage conditioned medium (MCM) was added to HGF culture on each wound dressing material, and the supernatants were examined in a similar manner. HGF growth on each wound dressing material was twice more than control and became confluent for 144 hours. The growth on chitin was the highest of all materials. FGF production by macrophages was highest when the cells were cultured on LPDS. On the other hand, when MCM was added to the HGF culture on each material, FGF production in only LPDS was more than that of control. In the supernatants of HGF cultured on chitin and CAS, FGF production was lower than control. EGF production of macrophages was highest when the cells were cultured on chitin. When HGF was cultured on each material with or without MCM, EGF production was not detected.

In vitro production and subsequent transplantation of a living skin substitute in rat model.

Three different transplants were generated for in vitro production of a living skin substitute in a rat animal model. In all cases epithelial cells from a small skin biopsy were grown in cell culture. Compound 1 consisted of cells outgrowing on lyophilized human dura mater. Compound 2 was fabricated with lyophilized porcine dermis. In compound 3 a lamella of dehydrated human fascia lata was seeded with epidermal cells. These skin substitutes were used to cover full-thickness skin defects. The production of a 6 cm2 substitute required 4-5 weeks time. After grafting autologous skin substitutes from compounds 1 and 2, vascularization and integration of the grafts failed to occur with 3 weeks. In contrast, transplantation of compound 3 resulted in the complete epithelialization of wound beds within 2-3 weeks accompanied by permanent integration of the skin substitute. Histological examination 1 year after grafting showed a dense, uniform structure of collagen fibers with an overlying epithelium of 4-6 cell layers. Secondary derivatives such as hair follicles and sweat glands were absent. When the fascia in compound 3 was replaced by a collagen lattice populated with cultured fibroblasts, transplantation results were unsatisfactory because of the deficient tensile strength of the collagen lattice.

Grafting of the buccal fat pad into palatal defects

Grafting of the buccal fat pad was performed in combination with lyophilized porcine dermis in six cases of palatal defects. The use of lyophilized porcine dermis not only simplified the surgical procedure but also permitted a proper prosthetic rehabilitation. This technique proved to have more advantages for palatal defects.

Effect of interpolymer complex formation on bioadhesive property and drug release phenomenon of compressed tablet consisting of chitosan and sodium hyaluronate.

The bioadhesion property of tablets consisting of chitosan (CS) and sodium hyaluronate (HA) was investigated using a lyophilized porcine dermis as a model of mucous membrane. Release phenomena of brilliant blue FCF (BBL) from the CS-HA tablets were also studied. BBL was employed as a model compound of water-soluble drugs. Strong adhesion forces were observed when the tablets were prepared from HA alone or a physical mixture of CS and HA. The adhesion of CS tablets was also obtained but it was rather weak. No effect of pH values in the media was observed on the adhesion force in these tablets. On the other hand, the release rate of BBL from CS-HA tablets was greatly affected by the change of the polymer mixing ratio, suggesting a possible interaction between CS and HA in the tablet following water penetration into the tablet.

Effects of atelocollagen on the wound healing reaction following palatal gingivectomy in rats

Collagen membrane preparations have been manufactured with the aim of enhancing wound healing following periodontal surgery. After cross-linking by various processing methods (with ultraviolet radiation or hexamethylenediisocyanate) and to various extents, atelocollagen membranes were applied into dissection sites within palatal gingival tissue. Applied atelocollagen was histopathologically compared with applied lyophilized porcine dermis (LPD) and controls in rats, with regard to the time course of healing. The atelocollagen-applied group showed more satisfactory regeneration of the epithelium and connective tissue in an artificially created gingival defect than did the control group or the LPD-applied group. Epithelial downgrowth along the root surface was significantly suppressed by the use of atelocollagen. In addition, the post-operative inflammatory reaction and foreign body giant cell reaction subsided rapidly after surgery in the atelocollgen-applied group. Our results show that the use of atelocollagen membrane in periodontal wounds should be the method of choice.

Orbital floor repair with lyophilized porcine dermis

Orbital floor repair with lyophilized porcine dermis

頬脂肪体有茎移植による口蓋欠損の閉鎖手術

Pedicled graft of buccal fat pad with lyophilized porcine dermis was used for the closure of 6 cases of palatal defects due to surgery of maxillary tumors. In four cases the oroantral and/or oronasal communications were closed, and in two cases exposed bone and muscles were covered. Three of 6 cases were of squamous cell carcinoma originating from gingiva and three were of either ameloblastoma or pleomorphic adenoma.Results of 6 cases to which this method was applied are as follows.1. This method could be applied to large palatal defects; in our cases the maximum defect size was 60×50×30mm.2. Epithelialization generally occurred in about two weeks in conjunction with dissolution of the lyophilized porcine dermis.3. The epithelialized tissue possessed similar characteritics to normal palatal mucosa.4. Epithelialization was not affected by either radiotherapy or chemotherapy.

Orbital floor repair with lyophilized porcine dermis

Various implants have been used to repair defects in orbital walls. Few are fully biocompatible. The indications for repair of a defect of the orbital floor are reviewed, and the suitability in selected cases of placement of lyophilized porcine dermis (xenograft) is discussed.

Porcine Dermis Dressings in Epidermolysis Bullosa

<h3>To the Editor.—</h3> The management of the severe forms of epidermolysis bullosa is a task that requires the highest standard of nursing skills. Often the results, despite intense effort, are disappointing. We report a case of the lethalis variant of epidermolysis bullosa in which the denuded areas of skin were dressed with lyophilized porcine dermis (Ethicon Corethium 2). Unfortunately, the patient died owing to inhalation of vomit 12 days after the treatment began, and a full trial of this treatment was not possible. The results in the early stages were sufficiently encouraging, however, to prompt us to report this case. <h3>Report of a Case.—</h3> The patient, a girl, was born at 37 weeks' gestation. At birth, blistering was evident over the dorsum of both hands, and the fingernails were dystrophic. Epidermal loss was present around the umbilicus, the knees, and the lower legs. Three days after birth, 10% of the total skin surface area was affected (mainly over the lower limbs), and mucous membrane involvement of the mouth had occurred.