Biocompatibility of carboxymethyl chitosan membranes with human skin melanocytes / 中华皮肤科杂志

Objective To study the biocompatibility of carboxymethyl chitosan (CMCS) membrane with melanocytes from healthy human skin,and to investigate the feasibility to transport and carry melanocytes by using CMCS membrane.Methods CMCS membrane was prepared by a casting method combined with a glutaraldehydebased cross-linking method.Melanocytes were isolated from the foreskin of healthy men,and subjected to primary culture and subculture.The third-passage melanocytes were classified into two groups to be cultured on the CMCS membrane (test group) or traditional culture plates (control group).Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of melanocytes,and a sodium hydroxide-based lysis method to determine melanin content.HMB45 staining was conducted,and tyrosinase activity was estimated for melanocytes.Results Inverted microscopy showed that melanocytes were evenly distributed on the CMCS membrane with a normal shape.The melanocytes adherent to the CMCS membrane stained positive for anti-HMB45 monoclonal antibody.The growth curve of the melanocytes on the CMCS membrane,which was obtained from MTT assay,demonstrated that CMCS membrane could support the normal growth of melanocytes.No significant difference was observed between the test group and control group in melanin content (0.083 ± 0.015 vs.0.066 ± 0.008,t =2.38,P ＞ 0.01) or tyrosinase activity (0.234 ± 0.083 vs.0.241 ± 0.061,t =0.23,P ＞ 0.05).Conclusion CMCS membrane can maintain the normal biological activity of melanocytes and have good biocompatibility with skin melanocytes.

Clinical evaluation and induced corneal vascularization study by native and anionic collagen membranes in rabbits corneas / Avaliação clínica e estudo da vascularização corneal induzida pelas membranas de colágeno nativo e aniônico em córneas de coelhos

PURPOSE: To evaluate the corneal vascularization (CV) and the clinical aspects induced by interlamellar graft with native (NCM) and anionic (ACM) collagen membranes in rabbits corneas. METHODS: An interlamellar graft with a 0.25 x 0.25 cm NCM (group 1) or ACM (group 2) fragment was performed in the right eye (treated eye). In the left eye, an estromal tunnel was done (control eye). Sixteen rabbits were used, and they were subdivided into two experimental groups of eight animals each. The clinical evaluation was performed at the 1st, 3rd, 7th, 15th and 30th postoperative days. Corneal vascularization analysis was performed after 30 days by the Images Analizator System Leica Qwin-550®. RESULTS: After 7 days, corneal vascularization was observed at about 2.25 ± 0.71 mm (NCM) and at about 1.0 ± 1.69 mm (ACM), respectively, from the limbus in direction to the central cornea. After 15 days, CV increased in both groups (5.25 ± 1.03 mm - NCM; 2.0 ± 2.39 mm - ACM) and then progressively decreased until day 30 (2.25 ± 2.10 mm - NCM; 0.75 ± 2.12 mm - ACM). The statistical analysis indicated that the averages of the distances from the limb vessels to the grafts observed after 7 and 15 days had not differed statistically (p=0.17), and after 15 and 30 postoperative days had a tendency to differ statistically (p=0.09). The control eyes did not present any changes. CONCLUSION: The interlamellar graft with native and anionic collagen membranes induced corneal vascularization when applied to rabbit corneas, but anionic collagen membrane induced a smaller corneal vascularization when compared to native collagen membrane. Although further studies are required, the results found in this study demonstrated the usefulness of interlamellar graft with native and anionic collagen membranes in keratoplasties. These membranes consists in one more graft option for the surgical treatment of corneal repair in rabbits and others animals, when other forms of medical...

OBJETIVO: Avaliar os aspectos clínicos e vascularização corneal (VC) induzida pelo enxerto interlamelar das membranas de colágeno nativo (MCN) e de colágeno aniônico (MCA) em córneas de coelhos. MÉTODOS: Um fragmento com 0,25 x 0,25 cm de MCN (grupo 1) e MCA (grupo 2) foi realizado no olho direito (olho tratado) por enxertia interlamelar. No olho esquerdo (olho controle) foi realizado apenas um túnel estromal. No olho direito (olho controle) foi realizado apenas um túnel estromal. Dezesseis coelhos foram utilizados e foram divididos em dois grupos experimentais composto por oito animais cada. A avaliação clínica foi realizada aos 1, 3, 7, 15 e 30 dias de pós-operatório. A análise da vascularização corneal foi realizada após 30 dias pelo Sistema de analisador de imagens Leica Qwin-550®. RESULTADOS: Após 7 dias, a vascularização corneal do limbo em direção central da córnea observada foi de 2,25 ± 0,71 mm (MCN) e 1,0 ± 1,69 mm (ACM), respectivamente. Após 15 dias a vascularização corneal aumentou em ambos os grupos (5,25 ± 1,03 mm - MCN; 2,0 ± 2,39 mm - MCA), diminuindo até o 30º dia (2,25 ± 2,10 mm - MCN; 0,75 ± 2,12 mm - MCA). A análise estatística indicou que as médias das distâncias dos vasos do limbo em direção ao enxerto observadas após 7 e 15 dias não diferiram estatisticamente (p=0,17), e 15 e 30 dias de pós-operatório houve tendência a diferir estatisticamente (p=0,09). Os olhos controles não apresentaram nenhuma alteração. CONCLUSÃO: As membranas de colágeno nativo e de colágeno aniônico induzem a vascularização corneal quando aplicadas na córnea de coelhos por meio de enxertia interlamelar, mas membrana de colágeno ativo induz a pequena vascularização corneal quando comparada à membrana de colágeno aniônico. Embora estudos adicionais sejam necessários, os resultados encontrados no presente estudo demonstraram que as membranas de CN e CA possam ser úteis em ceratoplastias. Estas membranas consistem em mais uma opção de enxerto...

Biomechanical evaluation of microbial cellulose (Zoogloea sp.) and expanded polytetrafluoroethylene membranes as implants in repair of produced abdominal wall defects in rats

PURPOSE: To evaluate the Load of Rupture of implants of membranes of microbial cellulose (Zoogloea sp.) and extended polytetrafuoroethylene in sharp defects of abdominal wall of rats. METHODS: Sixty Wistar male rats, with a mean weight of 437,7g ± 40,9, anesthetized by a mixture of ketamine (5mg/100g) and xylazine (2mg/100g), were submitted to a rectangular (2x3cm) excision of the abdominal wall, including fascia, muscle and peritoneum, and treated with membranes of microbial cellulose (MC) (MC Group- 30 animals) or extended polytetrafluoroethylene (ePTFE) (ePTFE Group- 30 animals). Each group was subdivided in 14th POD, 28th POD and 60th POD Subgroups. Under anesthesia, animals were submitted to euthanasia at 14th POD, 28th POD and 60th POD for evaluation of Load of Rupture. RESULTS: Load of Rupture levels were significantly elevated (p<0, 05) among 14th, 28th and 60th postoperative days from each Group. When compared between groups, values of Load of Rupture were significantly larger (p<0, 05) in ePTFE Group than in MC Group. CONCLUSION: Resistance to strength at implant/host interface was more pronounced in PTFEe Group than in MC Group.

OBJETIVO: Avaliar a Carga de Ruptura de implantes de membranas de celulose microbiana (Zoogloea sp.) e de politetrafluoretileno expandido em defeitos agudos produzidos na parede abdominal de ratos. MÉTODOS: Sessenta ratos machos Wistar, com média de peso de 437,7g ± 40,9, anestesiados com uma mistura de cetamina (5mg/100g) e xilazina (2mg/100g), foram submetidos à excisão retangular (2x3cm) na parede ventral do abdômen, incluindo fáscia, músculo e peritônio. Subseqüentemente, foram tratados com implante de membranas de celulose microbiana (CM) (Grupo CM - 30 animais) ou de politetrafluoretileno expandido (PTFEe) (Grupo PTFEe - 30 animais). Cada grupo foi ainda subdividido nos Subgrupos 14º DPO, 28º DPO e 60º DPO. Os animais foram submetidos à eutanásia com doses letais de tiopental no 14º DPO, 28º DPO e 60º DPO, para avaliação da Carga de Ruptura na área do implante. RESULTADOS: Os níveis da Carga de Ruptura foram significativamente elevados (p<0,05) entre os Subgrupos 14º DPO, 28º DPO e 60º DPO de cada grupo estudado. Quando comparados entre Grupos, os valores da Carga de Ruptura foram significativamente maiores (p<0,05) no Grupo PTFEe do que no Grupo CM. CONCLUSÃO: A interface implante/hospedeiro apresentou maior resistência a tração no Grupo PTFEe do que no Grupo CM.

Avaliações clínica e morfométrica da capacidade angiogênica da membrana de quitosana em córneas de coelhos / Clinical and morphometric evaluations of the angiogenic capacity of chitosan membrane in rabbit corneas

OBJETIVO: Estudar a vascularização corneal (VC) induzida pela membrana de quitosana (MQ) implantada por enxertia interlamelar na córnea de coelhos. MÉTODOS: Foram utilizados 16 coelhos. No olho esquerdo procedeu-se enxertia interlamelar de um fragmento de 0,25 x 0,25 cm de MQ (olho tratado). No olho direito realizou-se apenas a microbolsa estromal (olho controle). Avaliaram-se clinicamente os animais aos 1, 3, 7, 15 e 30 dias de pós-operatório. Aos 30 dias mensurou-se a VC pelo Sistema Analisador de Imagens LEICA QWIN-550®. RESULTADOS: Aos sete dias observou-se VC a 1,5±0,93 mm do limbo em direção ao eixo visual. Aos 15 dias houve aumento da VC (4,75±3,20 mm), que se manteve aos 30 dias (4,25±4,10 mm). Os olhos controles não apresentaram quaisquer alterações oculares. Houve diferença estatística (p<0,05) entre as áreas corneais vascularizadas dos olhos tratados e controles aos 15 e 30 dias de pós-operatório. CONCLUSÕES: A MQ induziu angiogênese corneal quando aplicada à córnea de coelhos por enxertia interlamelar, a qual persistiu de forma leve até 30 dias de pós-operatório. Embora estudos adicionais sejam necessários a MQ poderá ser mais uma opção de membrana para enxertos em ceratoplastias.

PURPOSE: To evaluate corneal vascularization (CV) induced by interlamellar graft chitosan membrane (CM) in rabbit cornea. METHODS: An interlamellar graft with a 0.25 x 0.25 cm CM fragment was performed in the left eye (treated eye). In the right eye, an estromal tunnel was done (control eye). The clinical evaluation was done at 1, 3, 7, 15 and 30 days postoperatively. CV analysis was after 30 days by the Images Analizator System LEICA QWIN-550®. RESULTS: After 7 days, CV at 1.5±0.92 mm from the limbus in direction of the cornea axial area was observed. After 15 days CV increased (4.75±3.19 mm), remaining until day 30 (4.25±4.06 mm). The control eyes did not present any changes. There was a statistical differences of the vascularizated corneal areas between control and treated eyes from the 15th to the 30th postoperative day. CONCLUSION: The chitosan membrane induced corneal angiogenesis when applied to rabbit cornea through an interlamellar graft, which was maintained at low levels until 30 days postoperatively. Although further studies are necessary, the results found here demonstrated the usefulness of chitosan membrane in keratoplasties.

The development of a bioartificial liver and its application in acute liver failure patients / 中国普通外科杂志

Objective Using polysulfon fibers, a new bioartificial liver was developed. This study was to evaluate the efficacy of this bioartificial liver in the support of a disfunctioned liver. Methods Hepatocytes were procured from swine using Seglen′s methods. The bioartificial liver was constructed based on polysulfon bioreactor with a procurement of 10 10 hepatocytes, and was applied in 12 acute liver failure patients for 14 sessions. Each BAL treatment lasted 6 hours. The general conditions of the patients and the biochemical parameters were evaluated. Results After treatment with bioartificial liver, ammonia, prothrombin time and total bilirubin level significantly decreased (all P

Surgical treatment for severe ocular rupture with blood staining of cornea and non-light perception / 中华眼底病杂志

Objective To evaluate the effects of surgical treatment for severe ocular rupture with blood staining of cornea and non-light perception, and analyze the relative factors. Methods Seven severely ruptured eyes of 7 patients with blood staining of cornea and non-light perception underwent second-stage penetrating keratoplasty combined with vitrectomy using temporary keratoprosthesis. All injured eyes had blood staining of cornea, hemorrhage in anterior chamber and vitreous, and choroidal and retinal detachment before the second-stage surgery. The average interval of the two surgical stages was 18 days (12-21 days). The preoperative visual acuity was non-light perception in all injured eyes with the mean intraocular pressure of 3 mm Hg (1 mm Hg=0.133 kPa) (2- 5 mm Hg). The mean follow-up period was 12 months (6-30 months). Results The postoperative visual acuity was better than light perception in 5 eyes with the best corrected visual acuity of light perception to 0.06. The retina was attached in 5 eyes (5/7). The mean postoperative intraocular pressure was 12 mm Hg (5- 15 mm Hg) which was significantly higher than the preoperative one (P