Jurandir Marcondes Ribas Filho

Effects of a highly concentrated platelet-rich plasma on the bone repair using non-critical defects in the calvaria of rabbits

PURPOSE To verify the effect of highly concentrated platelet-rich plasma (hPRP) in the pathways of bone repair using non-critical defects in the calvaria of rabbits. METHODS The hPRP was produced from collected venous blood of 21 rabbits. Four non-critical defects of 8 mm in diameter were created on the calvaria of each animal. The defects were all treated differently: autogenous particled bone (APB, group 1), autogenous particled bone associated with hPRP (APB + hPRP, group 2), isolated hPRP (group 3), and blood clot (control, group 4). Animals were submitted to euthanasia on the 2nd, 4th and 6th week postoperatively. Histological and histomorphometric analysis were carried through. RESULTS After two weeks, groups 1 and 2 were in more advanced stage of repair than 3 and 4. At this period, comparing the groups 1 and 2, no significant differences were found between both, which also happened between the groups 3 and 4. However, after four and six weeks, the group 1 showed a more advanced stage of repair among all the other studied groups, while group 2 was in more advanced signs of bone repair than groups 3 and 4. Comparing groups 3 and 4, after four and six weeks, the least advanced stage of bone repair was found to be within group 3. CONCLUSION The use of a highly concentrated PRP was considered prejudicial to the repair of non-critical defects in the calvaria of rabbits, either in the association of autogenous particled bone, when compared to autogenous particled bone alone, or in its isolated form, when compared to blood clot (control).

Modified femtosecond laser-assisted sutureless anterior lamellar keratoplasty.

Abstract: A variation of the femtosecond laser–assisted sutureless anterior lamellar keratoplasty technique using a femtosecond laser incision for surgical management of anterior corneal disease is described. Six patients with corneal scars were treated with the laser to create a horizontal lamellar bed interface in the cornea of the donor and recipient eyes, with a manual partial-thickness vertical trephination to complete the excisions. This technique allows matching of donor and host tissue dimensions with precise tissue apposition and greater surface area for healing. No intraoperative adverse events were observed. One patient developed epithelial ingrowth, requiring a successful surgical intervention.

Neoplasias astrocitárias e correlação com as proteínas p53 mutada e Ki-67

The astrocytic neoplasms respond by 60% of the central nervous system tumors, being the study of the molecular biology an important step for the understanding of the genesis and biological behavior of these diseases. The Ki-67 proteins, which are markers of the cellular proliferation, and p53, which is the product of the tumor suppressor gene TP53, are both important tumoral markers. This study intends to identify and quantify the Ki-67 and p53 proteins in astrocytic tumors of different grades of malignancy, as well as to analyze their relations with age and gender. Ki-67 and p53 proteins in 47 patients with surgically resected astrocytic neoplasms were studied through immunohistochemistry. They have been previously classified and reviewed concerning their histological grade, as suggested by the World Health Organization. The immunomarked cellular nuclei were quantified by the program Imagelab-softium for the absolute parametric reason between the nuclei of the positive cells and the total amount of tumoral cells, being counted 1000 cells. The lineation used has been transversal not controlled. For the statistical analysis the variables were divided into groups. For the Ki-67 they were absent, <5% and >5% and for p53 they were absent (0), <25% (1+), between 25 and 50% (2+), between 50 and 75% (3+), and higher than 75% (4+). Ki-67 was present in 37 cases (78.72%) evidencing a correlation with a higher malignancy degree (p<0,001). p53 was present in 14 cases (35.13%) with a higher correlation with astrocytoma grade IV (p=0.59). There has not been a statistically significant correlation between p53 and Ki-67, as well as among these variables, age and gender. The hypotheses of a greater presence of Ki-67 and p53 in astrocytic neoplasms with a higher degree of malignancy, except for the correlation between grade III and p53, is corroborated by the results of this study.

Histopathological reaction over prosthesis surface covered with silicone and polyurethane foam implanted in rats

PURPOSES To evaluate whether polyurethane foam leads more intense foreign-body reaction than silicone foam. To compare the vascularization of the capsules surrounding the foam implants. To investigate if the capsule of polyurethane foam implanted has greater amount of collagen than that of silicone foam. METHODS Sixty-four young male Wistar rats were allocated into two groups: polyurethane foam and silicone foam. Subcutaneous discs were implanted into the dorsum of the animals in both groups. The capsules were assessed 28 days, two months, three months and six months postoperatively. Microscopic analysis with H&E stain was performed to evaluate the acute and chronic inflammatory process, foreign-body reaction and neovascularization. The analysis with picrosirius red was performed using the ImageProPlus software, to measure the number of vessels and collagen types I and III. RESULTS There were no statistical differences between the two groups regarding the acute and chronic inflammatory processes. All rats from the polyurethane group, in all times, exhibited moderate or intense foreign-body reaction, with statistic significant difference (p=0.046) when compared with the silicone group, in which the reaction was either mild or nonexistent at two months. Vascular proliferation was significantly different between the groups at 28 days (p=0.0002), with the polyurethane group displaying greater neovascularization with H&E stain. Similar results were obtained with picrosirius red, which revealed in the polyurethane group a much greater number of vessels than in the silicone group (p=0.001). The collagen area was larger in the polyurethane group, significantly at 28 days (p=0.001) and at two months (p=0.030). CONCLUSIONS Polyurethane foam elicited more intense foreign-body reaction when compared with silicone foam. The number of vessels was higher in the capsules of the polyurethane foam implants 28 days after the operation. The capsule of the polyurethane foam implants showed a greater amount of collagen than that of the silicone foam implants.

Estudo comparativo do uso de extrato de Pfaffia glomerata e do laser de baixa potência (Hélio-Neônio) na cicatrização de feridas em ratos

BACKGROUND: Pfaffia glomerata is a plant used in folk medicine as tonic, antidiabetic, to improve the healing process, neutralize stomach upset and antirheumatic. AIM: To compare the wound contraction and the neovascularization with the use of plant extract of Pfaffia glomerata (Spreng.) Pedersen, Amaranthaceae, and low power laser in rats. METHODS: It was used 40 Wistar rats in which surgical wounds with a punch of 3 mm in diameter at the top right of the back and no substance was applied at this site, and similar wounds in the lower left side had applicated extract of P. glomerata (Spreng.) Pedersen, Amaranthaceae, control groups and plants in the same animal. Another 40 animals had the low power laser application. On dates scheduled within 48 hours, one, two and three weeks measures were taken and wound contraction observed. Microscopic results were analyzed using immunohistochemistry with Factor VIII to observe the vascular density. RESULTS: It was possible to observe macroscopically no statistic significant difference with respect to the contraction of the wound between the groups plant and laser, both getting better results than the control group. This variable showed a statistical significance with the laser group when was compared the subgroups 48 hours X one week (p=0,008). Statistical analysis of Factor VIII showed an statistic significance in subgroup one week of the plant with the laser (p=0.09). CONCLUSIONS: There was no statistic significant difference between the plant and laser groups with respect to contraction of the wound. On microscopic analysis, the group plant earned more than the laser group with relation to neovascularization in subgroup one week, and after that occured a balance between them.

Wound healing using ionic silver dressing and nonocrystalline silver dressing in rats

PURPOSE To investigate the results of the healing process on surgical wounds in the back of Wistar rats using nanocristaline and ionic silver dressing. METHODS Sixty rats Wistar were submitted to surgical wounds with punch of 8 mm in diameter. In 30 animals (groups PN - nanocristaline and AD - control) two surgical wounds were done diametrically opposite on the upper back side. On the right side was used nanocristaline (PN) silver dressing and on the left side, distilled water dressing (AD). On the other group of 30 rats, only one wound was made with the punch, on the right side, and was used ionic silver dressing. So, the groups were divided into three subgroups, according to the day of death (7(th), 14(th) and 21(st) day). In each of these days the wounds diameter were measured to evaluate the wound contraction. Microscopic data were analyzed using the H&E staining to verify the inflammatory process and neovascularization. The Masson trichrome staining was used to verify the fibrosis. RESULTS Macroscopically only the subgroup of 21(st) day showed statistical significance; between the groups AD and PI inflammatory process appeared in the 7(th) day subgroup in 90% of the cases. In neovascularization there was statistical significance between the groups PN and AD in the subgroup of 7(th) day. Fibrosis did not show statistical significance in the studied groups. CONCLUSIONS In relation to wound contraction, PN and PI groups showed better results than the AD group. In regard to histological analysis, H&E staining showed that there was presence of inflammation in all groups, and at the end, the control group (AD) on 7(th) day, was superior to PN and PI groups. In relationship to fibrosis, no differences were obtained among groups.

Action of tacrolimus on Wistar rat kidneys implanted with Walker 256 carcinosarcoma.

PURPOSE To evaluate the development of Walker 256 tumor in male Wistar rats treated with tacrolimus using an experimental kidney tumor model. METHODS 40 male Wistar rats were divided into four groups: Tumor group (TU) (n=10), Tacrolimus-Tumor group (TT) (n=10), Tacrolimus group (TC) (n=10) and Control group (C) (n=10). Treatment with tacrolimus was performed in groups TT and TC. Under anesthesia, the right kidney of each animal of TU and TT was accessed through a supraumbilical incision and inoculated with a 0.1 mL solution containing 2 x 10(6) tumor cells (Walker 256 carcinosarcoma tumor cells). Group TC was treated with a saline solution. All the animals of groups TC and TT were treated with tacrolimus (5mg/kg/day) by gavage for 15 days. TU group animals received saline by gavage for 15 days. On the 15th postoperative day, all animals were submitted to euthanasia and blood sampling for analysis of serum creatinine (Cr) and blood urea nitrogen (BUN). Abdominal gross examination was performed, the right kidney removed and prepared for histological analysis by hematoxylin-eosin staining. The resulting data were submitted to statistical analysis by ANOVA. RESULTS Statistical significance was found when comparing creatinine level between groups TU, TT and TC -TT group culminated with a marked increased in creatinine levels (Cr=1.013 + or - 0.3028 mg/mL), TU group (Cr=0.5670 + or - 0.03536 mg/dL) P=0.00256, TC group (Cr =0.711 + or - 0.1653 mg/mL) P= 0.02832. Statistical significance was found when comparing BUN levels in TT group (71.32 + or - 17.14 mg/mL), compared with TU group (45.83 + or - 5.046 mg/dL), P=0.000318. There were no statistically significant differences between groups TT and TC (61.23 + or - 9.503 mg/mL) P=0.7242. Histological analysis showed a poor evolution in TT group with multiple foci of hemorrhage and cortical invasion by the Walker tumor. CONCLUSION The Tacrolimus-treated group developed a more aggressive tumor and a drug-related nephrotoxic effect.

Angiogenesis, fibrinogenesis and presence of synechiae after exeresis of a swine vocal fold mucosal microflap and use of topical mitomycin-C

PURPOSE To evaluate swine vocal fold healing in a period of 30 days after topical mitomycin-C application. METHODS Twelve swine underwent exeresis of mucosal flaps from the free edge of the anterior third of both vocal folds with a cold instrument (laryngeal scissors). The animals were divided into two groups: EG (Experimental Group), consisting of 6 animals undergoing topical MMC application (4 mg/dL) on the operated area for 4 minutes; CG (Control Group), 6 animals undergoing topical saline solution application on the operated area for 4 minutes. After 30 days, the animals were sacrificed and the larynges were collected and examined for the presence of synechiae as well as a histological immunohistochemical assessment of immature and mature collagen deposition, number of blood vessels and myofibroblasts. RESULTS Mature collagen deposition in the EG was 452.12 microm(2) and 1332.31 microm(2) in the CG; immature collagen deposition was 1511.73 microm(2) in the EG and 1020.61 microm(2) in the CG. The number of myofibroblasts was 1.556 in the EG and 3.583 in the CG. The number of blood vessels was 2.565 in EG and 6.917 in the CG. There were no synechiae in the two studied groups. CONCLUSIONS There was an increase in immature collagen deposition in the experimental group when compared with the control group. There was a decrease in mature collagen deposition in the experimental group when compared with the control group. There was a decrease in the number of myofibroblasts in the experimental group when compared with the control group. A decrease in blood vessels was observed in the experimental group when compared with the control group. There was no synechia formation in either studied group.

Expressão citofotométrica do fator de proliferação celular ki-67 no bócio colóide e no carcinoma papilífero da tireóide

OBJECTIVE To compare the cytophotometric quantitative expression of Ki-67 cellular proliferation factor in the colloid goiter with papillary carcinoma of the thyroid. METHODS The protein Ki-67 was studied with immunohistochemistry in 20 cases of papillary carcinoma of the thyroid and 12 cases of colloid goiter. The immunomarked cell nuclei were quantified through the software SAMBA 4000 and analyzed by software IMMUNO, considering variables index marker and optical density. The coefficient of the Spearman rank correlation and the non-parametric test of Mann-Whitney were estimated. RESULTS There is significant difference between the goiter colloid and the papillary carcinoma of the thyroid in Ki-67 measurements, being bigger in papillary carcinomas. No difference was found in optical density. The correlation coefficient between the index marker and the optic density was 0,78. In colloid goiter, there was positive and significant association between the index marker and the optic density. For the papillary carcinoma of the thyroid the correlation between index marker and optic density was 0,18 (p = 0,572). There was no association between the index marker and the optic density in the carcinoma papillary of the thyroid. CONCLUSION The cytophotometric expression of the Ki-67 showed higher cellular proliferation in the papillary carcinoma of the thyroid in comparison with in the colloid goiter.

Comparison between electrocautery and fibrin selant after hepatectomy in rats

OBJECTIVE To compare between electrocautery and fibrin sealant hemostasis in rats after partial hepatectomy. METHODS we used 24 Wistar rats, which were submitted to 30% hepatic resection, divided into two groups of 12 animals each: Group Electrocautery and Group Tachosil(r). These animals were evaluated after three and 14 days. We assessed the presence of complications, laboratory tests and histological exam of the recovered liver. RESULTS the presence of abscess was more prevalent in the electrocautery group. The observed adhesions were more pronounced in the electrocautery group, both in frequency and in intensity, after three and 14 days. There were no deaths in either group. As for laboratory analysis, after three days the hematocrit was lower in the TachoSil(r) Group. The elevation of AST and ALT were more pronounced in the electrocautery group (p = 0.002 and p = 0.004) in three days. Histological analysis of specimens collected on the third day after surgery showed similar results in both groups for the presence of polymorphonuclear cells, whereas mononuclear was more evident in the TachoSil(r) group. We also observed that angiogenesis, although present in both groups, was more pronounced in the TachoSil(r) group (p = 0.030). However, on the 14th day angiogenesis was more pronounced in the electrocautery group, but without statistical significance. CONCLUSION hemostasis achieved by the groups was similar; however, the use of electrocautery was associated with infections, adhesions at higher grades and elevated liver enzymes.