Micro-ct findings of concentrated growth factors (cgf) on bone healing in masquelet's technique-an experimental study in rabbits.

INTRODUCTION: A recent histopathological and immunohistochemical study has proved that the addition of concentrated growth factors (CGF) to the Masquelet's technique contributes to the quality of the membrane formed, in respect of inducing inflammation and proliferation, maintaining vascularization on large diaphyseal bone defects, and increasing the number of stem cells. The aim of the study is comparison of radiological results of this combination treatment by micro-CT. MATERIALS AND METHODS: The study was planned on a critical bone defect model in rabbit radius. Group I and Group III were the control groups to which only the Masquelet's technique is applied. Group II and Group IV were CGF groups in addition to the Masquelet's technique. CGF was prepared by centrifugation of rabbit's own blood. For early phase, Groups I and II were evaluated in the 8th week, while for late phase, Group III and Group IV were evaluated in the 12th week. Groups were compared in terms of bony union radiologically by micro-CT(µCT) (New Bone Volume (NBV), Total Bone Volume (TBV) and NBV/TBV) and histopathologically. RESULTS: The structural parameters, including NBV, TBV, NBV/TBV were higher in the early- (8th week) and late-phase (12th week) CGF group. There was no statistically significant difference between CGF and control groups in early phase, (p = 0.153), while in late phase, CGF group was significantly higher of new bone volume than the control group, 246.3 mm3 (196.1-258) and 169.6 mm3 (154.3-235.9), respectively (p = 0.028). For early phase, control group was significantly lower than late-phase control group, 121.8 mm3 (88.8-144.4) and 169.6 mm3 (154.3-235.9), respectively (p = 0.006). The ratio of New Bone Volume to Total Bone Volume (NBV/TBV ratio) in CGF groups was significantly higher compared to the control groups 27.3% (24.7-29.6), 35.3% (32.1-38.6) (p = 0.032) and 39.7% (36.7-41.6), 55.3% (52-57.5) (p = 0.002), respectively. Histopathologically, Microscopic New Bone Formation had no statistically significant difference between control and CGF groups in early phase (8th week) (p = 0.153), while in late phase (12th week), CGF group had significantly higher amount of new bone formation than the control group, 0.29 µm2 (0.27-0.36), 0.51 µm2 (0.42-0.59), respectively (p = 0.008). CONCLUSION: The addition of CGF to the Masquelet's technique is an important method for supporting new bone formation in large diaphyseal bone defects. LEVEL EVIDENCE: Level III, therapeutic/care management.

Can the Combination of Simvastatin and Melatonin Create a Synergistic Effect on Bone Regeneration?

PURPOSE: The present study evaluated the potential bone regeneration capacity of combining melatonin and simvastatin, with a goal of producing more osteogenic bone substitutes. MATERIALS AND METHODS: A total of 48 male Wistar rats were randomly divided into 4 groups. The following were administered into critical-sized calvarial defects of the rats: Group I-human allograft; Group II-human allograft + 10 mg melatonin; Group III-human allograft + 0.1 mg simvastatin; and Group IV-human allograft + 10 mg melatonin + 0.1 mg simvastatin. Histopathologic, histomorphometric, and microcomputed tomographic evaluations were performed postprocedurally at 4 and 8 weeks. A P value < .05 was considered significant for all evaluations. RESULTS: Groups II and III had significantly superior regeneration compared to Group I at weeks 4 and 8. Group III had significantly superior regeneration compared to Group II, particularly in week 4. Group IV had significantly superior regeneration compared to all groups at week 8. CONCLUSIONS: The local administration of melatonin and simvastatin resulted in increased new bone mass and quality of bone microstructure than was seen in the control group. Simvastatin shortened the defect regeneration time more effectively than melatonin did. The combined use of melatonin and simvastatin provided a synergic effect on bone regeneration, particularly in the late phase of healing.

Primary ependymoma of the retropubic space in a male patient.

We report a case of primary intraabdominal ependymoma arising in the retropubic space of a male patient. An incidental intraabdominal mass was discovered in a 51-year-old man. Radiological studies revealed a 10 cm, solid and cystic tumor located in the Retzius fossa. Microscopically, the lesion was characterized by multiple cellular nodules composed of bland small cells forming true and pseudorosettes. No nuclear atypia, necrosis or increased mitotic activity was present. Neoplastic cells positive for AE1/3 and Cam5.2, and expressed patchy GFAP, and paranuclear dot-like to microvesicular EMA and D2-40, while S100, synaptophysin, PAX8, TLE1, WT1, inhibin, calretinin, Melan-A, and HMB45 were negative. Electron microscopy findings supported the diagnosis: 1) Frequent intracytoplasmic vacuoles with short and redundant microvilli and few cilia 2) lung intercellular junctions. The patient is alive with no evidence of disease for 4 years. Pathologists should be aware that rare extraneural ependymomas may occur in the Retzius space, even in a male patient. This entity should be kept in mind especially when the differential diagnosis is metastatic carcinoma with an unusual morphology and immune profile.

Immunopathology in drug resistant mesial temporal lobe epilepsy with different types of hippocampal sclerosis.

PURPOSE: There is evidence that autoimmunity has a specific role in temporal lobe seizures of limbic encephalitis patients. Our aim in this study was to investigate any histopathological clues of autoimmune process in refractory temporal lobe epilepsy (TLE) patients with different pathologically proven hippocampal sclerosis (HS) types. METHODS: 22 patients who had undergone epilepsy surgery due to mesial TLE-HS were included. The sera of patients are tested for neuronal antibodies to N-methyl-D-aspartate receptors (NMDAR), leucine-rich, glioma inactivated 1 (LGI1), contactin-associated protein 2 (CASPR2), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), gamma-aminobutyric acid B receptor (GABABR) and glutamic acid decarboxylase (GAD). Pathological and immunohistochemical investigations including neuronal nuclei (NeuN), NMDAR, GAD, glial fibrillary acidic protein (GFAP), CD8+-CD3+ lymphocytes and immunoglobulin G (IgG) were done. Patients were grouped according to type of HS. Clinical features and immunohistochemical changes were defined in these groups. RESULTS: Available sera of 15 patients did not have any neuronal antibodies. Thirteen of 22 patients had HS type 1, three had HS type 2 and two had HS type 3. According to immunohistochemical investigations CD3+ and CD8+ T cell infiltration was more prominent in the hippocampus of patients with classical HS (International League Against Epilepsy (ILAE) Type 1 HS) and there was a significant negative correlation between epilepsy duration and numbers of CD3+-CD8+ lymphocytes in temporal lobe parenchyma. CONCLUSION: The role of T cell-mediated immunopathology and immunopathological difference in a variety of drug resistant TLE-H2S patients was suggested. These findings can be helpful in understanding the epileptogenicity of HS.

Isotretinoin's action against cisplatin-induced ototoxicity in rats.

Current data do not support the routine use of any agent to prevent cisplatin ototoxicity. Although there are various diseases in which derivatives of vitamin A are used due to their antioxidant effects, there is no study for prevention from ototoxicity. In this study, the protective effect of isotretinoin was investigated on cisplatin ototoxicity in rats. 21 Wistar Albino rats were divided randomly into 3 groups. Group I: cisplatin, Group II: cisplatin + isotretinoin and Group III was the control group. Hearing assessment of all rats was done with ABR and DPOAE tests before and after the procedure. After the procedure, cochleas were resected and transmission electron microscopic examination was performed. Our DPOAE and ABR findings showed that isotretinoin has protective effects on cisplatin ototoxicity. According to transmission electron microscopic findings, isotretinoin has protective effects on cell integrity. We think that new experimental and clinical studies to be carried out in this regard may give us a new option on prevention of cochlea from ototoxicity.

ADCK4-Associated Glomerulopathy Causes Adolescence-Onset FSGS.

Hereditary defects of coenzyme Q10 biosynthesis cause steroid-resistant nephrotic syndrome (SRNS) as part of multiorgan involvement but may also contribute to isolated SRNS. Here, we report 26 patients from 12 families with recessive mutations in ADCK4. Mutation detection rate was 1.9% among 534 consecutively screened cases. Patients with ADCK4 mutations showed a largely renal-limited phenotype, with three subjects exhibiting occasional seizures, one subject exhibiting mild mental retardation, and one subject exhibiting retinitis pigmentosa. ADCK4 nephropathy presented during adolescence (median age, 14.1 years) with nephrotic-range proteinuria in 44% of patients and advanced CKD in 46% of patients at time of diagnosis. Renal biopsy specimens uniformly showed FSGS. Whereas 47% and 36% of patients with mutations in WT1 and NPHS2, respectively, progressed to ESRD before 10 years of age, ESRD occurred almost exclusively in the second decade of life in ADCK4 nephropathy. However, CKD progressed much faster during adolescence in ADCK4 than in WT1 and NPHS2 nephropathy, resulting in similar cumulative ESRD rates (>85% for each disorder) in the third decade of life. In conclusion, ADCK4-related glomerulopathy is an important novel differential diagnosis in adolescents with SRNS/FSGS and/or CKD of unknown origin.

Epidermolysis Bullosa with Pyloric Atresia and Aplasia Cutis in a Newborn Due to Homozygous Mutation in ITGB4.

BACKGROUND: Epidermolysis bullosa with pyloric atresia (EB-PA) is an autosomal recessive disorder due to mutations in ITGA6 and/or ITGB4, resulting in altered expression of α6ß4 integrin. EB-PA can also occur with aplasia cutis. CASE REPORT: We present a newborn with EB-PA and aplasia cutis, born of consanguineous parents, with a homozygous c.3793+1G>A mutation affecting ITGB4, previously described only in the heterozygous state with other mutations. CONCLUSION: The previously unreported homozygous c.3793+1G>A mutation affecting ITGB4 causes a severe form of junctional epidermolysis bullosa with pyloric atresia and aplasia cutis.

Mutations in ANKS6 cause a nephronophthisis-like phenotype with ESRD.

Nephronophthisis (NPHP) is one of the most common genetic causes of CKD; however, the underlying genetic abnormalities have been established in <50% of patients. We performed genome-wide analysis followed by targeted resequencing in a Turkish consanguineous multiplex family and identified a canonic splice site mutation in ANKS6 associated with an NPHP-like phenotype. Furthermore, we identified four additional ANKS6 variants in a cohort of 56 unrelated patients diagnosed with CKD due to nephronophthisis, chronic GN, interstitial nephritis, or unknown etiology. Immunohistochemistry in human embryonic kidney tissue demonstrated that the expression patterns of ANKS6 change substantially during development. Furthermore, we detected increased levels of both total and active ß-catenin in precystic tubuli in Han:SPRD Cy/+ rats. Overall, these data indicate the importance of ANKS6 in human kidney development and suggest a mechanism by which mutations in ANKS6 may contribute to an NPHP-like phenotype in humans.

Disruption of PTPRO causes childhood-onset nephrotic syndrome.

Idiopathic nephrotic syndrome (INS) is a genetically heterogeneous group of disorders characterized by proteinuria, hypoalbuminemia, and edema. Because it typically results in end-stage kidney disease, the steroid-resistant subtype (SRNS) of INS is especially important when it occurs in children. The present study included 29 affected and 22 normal individuals from 17 SRNS families; genome-wide analysis was performed with Affymetrix 250K SNP arrays followed by homozygosity mapping. A large homozygous stretch on chromosomal region 12p12 was identified in one consanguineous family with two affected siblings. Direct sequencing of protein tyrosine phosphatase receptor type O (PTPRO; also known as glomerular epithelial protein-1 [GLEPP1]) showed homozygous c.2627+1G>T donor splice-site mutation. This mutation causes skipping of the evolutionarily conserved exon 16 (p.Glu854_Trp876del) at the RNA level. Immunohistochemistry with GLEPP1 antibody showed a similar staining pattern in the podocytes of the diseased and control kidney tissues. We used a highly polymorphic intragenic DNA marker-D12S1303-to search for homozygosity in 120 Turkish and 13 non-Turkish individuals in the PodoNet registry. This analysis yielded 17 candidate families, and a distinct homozygous c.2745+1G>A donor splice-site mutation in PTPRO was further identified via DNA sequencing in a second Turkish family. This mutation causes skipping of exon 19, and this introduces a premature stop codon at the very beginning of exon 20 (p.Asn888Lysfs*3) and causes degradation of mRNA via nonsense-mediated decay. Immunohistochemical analysis showed complete absence of immunoreactive PTPRO. Ultrastructural alterations, such as diffuse foot process fusion and extensive microvillus transformation of podocytes, were observed via electron microscopy in both families. The present study introduces mutations in PTPRO as another cause of autosomal-recessive nephrotic syndrome.

Human dental pulp stem cells demonstrate better neural and epithelial stem cell properties than bone marrow-derived mesenchymal stem cells.

Dental pulp stem cells (hDP-SCs) were primarily derived from pulp tissues of primary incisors, exfoliated deciduous and permanent third molar teeth. To understand the characteristics of hDP-SCs from impacted third molar, proliferation capacities, gene expression profiles, phenotypic, ultrastructural, and differentiation characteristics were analyzed in comparison with human bone marrow-derived mesenchymal stem cells (hBM-MSCs), extensively. hDP-SCs showed more developed and metabolically active cells. Contrary to hBM-MSCs, hDP-SCs strongly expressed both cytokeratin (CK)-18 and -19, which could involve in odontoblast differentiation and dentine repair. The intrinsic neuro-glia characteristics of hDP-MSCs were demonstrated by the expression of several specific transcripts and proteins of neural stem cell and neurons. These cells not only differentiate into adipogenic, osteogenic, and chondrogenic lineage, but also share some special characteristics of expressing some neural stem cell and epithelial markers. Under defined conditions, hDP-SCs are able to differentiate into both neural and vascular endothelial cells in vitro. Dental pulp might provide an alternative source for human MSCs. hDP-SCs with a promising differentiation capacity could be easily isolated, and possible clinical use could be developed for neurodegenerative and oral diseases in the future.

Isolation and characterization of stem cells from pancreatic islet: pluripotency, differentiation potential and ultrastructural characteristics.

BACKGROUND AIMS: Stem cells (SC) in different locations have individual characteristics. Important questions to be answered include how these specialties are generated, what the mechanism underlying their generation is, and what their biologic and clinical merits are. A basic approach to answering these questions is to make comparisons between the differences and similarities among the various SC types. They may focus on aspects of biologic marker discovery, capacity of proliferation and differentiation, along with other characteristics. The aim of this study was to characterize in detail the SC isolated from pancreatic islet (PI) and compare their properties with bone marrow (BM)-derived mesenchymal stromal cells (MSC) of the rat. METHODS: Immunophenotypic characteristics, proliferation capacities, telomerase activities, pluripotent-related gene expressions, ultrastructure and the potential for multilineage differentiation of PI SC and BM MSC were studied. RESULTS: We found that PI SC expressed markers of embryonic SC (Oct-4, Sox-2 and Rex-1) and had a high proliferation capacity, proven also by high telomerase activities. Surprisingly, markers belonging to differentiated cells were expressed by these cells in a constitutive manner. PI SC ultrastructure showed more developed and metabolically active cells. CONCLUSIONS: The immunocytochemical identification of both PI SC and BM MSC was demonstrated to be typical MSC. Without stimulation of differentiation markers of adipogenic, chondrogenic, neurogenic, myogenic and osteogenic cells in these SC, the expression of those markers might explain their multilineage differentiation potential. We suggest that, by reason of the respectively high telomerase activity in PI SC, they could be better candidates than BM MSC for cell replacement therapy of type 1 diabetes.

Effects of Topical Ozone Application on Outcomes after Accelerated Corneal Collagen Cross-linking: An Experimental Study.

PURPOSE: Ozone is a trioxygen molecule that spontaneously degrades into oxygen and oxygen free radicals. This study was designed to assess the effects of topical ozone application on outcomes after corneal collagen cross-linking (CXL). METHODS: Enucleated fresh cadaver yearling sheep eyes (n = 28) were divided into five groups: control (C, n = 6), sham (S, n = 6), ozone only (Z, n = 6), CXL only (X, n = 5), and Ozone + CXL (ZX, n = 5). In all groups, except C, the epithelial layer was removed. In group Z, 20 µg/mL liquid ozone was topically applied. In group X, CXL was performed in the accelerated pulse mode. In group ZX, both CXL and ozone were applied. Post-interventional oxygen levels were determined and corneal confocal microscopy and optical coherence tomography were performed. Corneas were evaluated using light and electron microscopy. RESULTS: Pre-interventional central corneal thickness (CCT) was highest in the control group and considerably similar in the remaining groups (P = 0.006). Pre- and post-interventional CCT were significantly different in the ozonated groups (Z and ZX) (P = 0.028; P = 0.043). Demarcation line depths were similar in groups Z, X, and ZX (P = 0.343). Increased stromal tissue reflectivity was observed in groups Z, X, and ZX. Oxygen levels were higher in the ozonated groups (Z and ZX) (P = 0.006), and caspase activity was higher in the CXL groups (X and ZX) (P = 0.028) as compared to the other groups. Group ZX showed tighter, more regular, and parallel fibrils. CONCLUSION: Ozone increases corneal stromal oxygenation which can probably augment the effect of CXL. Future studies should investigate the safety and feasibility of ozone application during CXL.

Characterization of mesenchymal stem cells from rat bone marrow: ultrastructural properties, differentiation potential and immunophenotypic markers.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) can differentiate into many lineages. Although the growing interest in BM-MSCs has led to a number of characterization studies, some important biochemical and immunohistochemical properties are still lacking. In this study, morphological and immunophenotypic properties of BM-MSCs were examined in detail. Differentiation potential and growth kinetics of adult rat BM-MSCs were also determined. Immunohistochemistry and RT-PCR results indicated that BM-MSCs expressed myogenic (desmin, myogenin, myosin IIa, and alpha-SMA), neurogenic (gamma-enolase, MAP2a,b, c-fos, nestin, GFAP and beta III tubulin), and osteogenic (osteonectin, osteocalcin, osteopontin, Runx-2, BMP-2, BMP-4 and type I collagen) markers without stimulation towards differentiation. These expression patterns indicated why these cells can easily differentiate into multiple lineages both in vitro and in vivo. Ultrastructural characteristics of rBM-MSCs showed more developed and metabolically active cells.

Comparison of collagen biomatrix and omentum effectiveness on peripheral nerve regeneration.

Despite the presence of various nerve coaptation materials and techniques, achievement of the functional nerve regeneration is still inadequate. This study was aimed to compare the effectiveness of conduit composed of collagen biomatrix and omentum graft on peripheral nerve regeneration. Thirty-five male Wistar rats were divided into four groups. In the control group, the right sciatic nerve was skeletonized from the sciatic notch till the point of bifurcation. In the primary epineural repair group, the nerve was transected 1 cm proximal to the bifurcation with a sharp pair of micro scissors and then repaired with four epineural sutures. In the collagen biomatrix group, the epineural repaired nerve was wrapped with collagen biomatrix. In the collagen group, the epineural repaired nerve was wrapped with the nonpediculated omentum. Assessment of the nerve regeneration was based on functional (Walking Track Analysis, Electrophysiological Measurements), histological, and morphometric criteria. Light and electron microscopic examinations showed that collagen-biomatrix-wrapped specimens have the best regeneration. The electrophysiological study confirmed the recovery of electrical activity in the regenerated axons.

The effect of mitomycin C as fibrosis preventive agent during craniectomies.

OBJECT: The authors conducted a study to determine the effectiveness of mitomycin C (MMC) in preventing epidural fibrosis in rats which underwent craniectomy. METHODS: Craniectomies were performed in the right frontoparietal region; after the procedure the animals had been divided in 2 groups of 10 each. Cotton pads soaked with 0.1 mg/ml MMC or saline (control) were applied to the operative sites. Four weeks after craniectomy the rats were sacrificed, and epidural fibrosis was evaluated histologically. The dura mater thickness, the density of epidural fibrosis, arachnoidal involvement, and bone regeneration were determined. RESULTS: No obvious adhesion formed in the rats in the MMC group, but severe epidural adhesions were found in control group. The duramater thickness, the density of epidural fibrosis, and arachnoidal involved rat number in the MMC group were significantly lower than in control groups. CONCLUSIONS: Epidural fibrosis can be a devastating condition that forms after craniectomy. Topical application of mitomycin C may be a successful method of preventing epidural fibrosis following craniectomy.

The comparison of the degree of apoptosis in ovaries and fallopian tubes between two different surgical interventions for tubal ligation: A rat model.

OBJECTIVE: To compare the degree of apoptosis in ovaries and tubal epithelium observed secondary to tubal ligation either by Pomeroy's method or bipolar electrocauterization in a rat model. MATERIAL AND METHODS: A total of 24 female Sprague-Dawley rats were randomly assigned into 3 study groups: control (n=8), Pomeroy (n=8), and the electrocauterization group (n=8). Apoptotic cells were detected on the primary, secondary, tertiary follicles of the ovaries, and on the tubal epithelium using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling. The apoptotic index was calculated for each group by the percentage of the stained cells. RESULTS: The apoptotic index of tubal epithelium was significantly higher in the bipolar electrocauterization group compared with the control and Pomeroy groups (3.1±0.8 vs. 1.4±1.0, p=0.018 and 2.0±1.2, p=0.03, respectively) whereas there was no significant difference between Pomeroy's method and the control group. The apoptotic index of primary follicles was higher in the bipolar electrocauterization group compared with the control and Pomeroy's method groups (3.4±0.5 vs. 1.2±0.4, p<0.001 and 1.8±0.8, p=0.005, respectively), but there was no significant difference between Pomeroy's method and the control group. The apoptotic index of secondary and tertiary follicles was similar for each group. CONCLUSION: Pomeroy's technique, as a permanent contraception method, is associated with lower apoptotic index on ovary and fallopian tube when compared with bipolar electrocauterization.

Prophylactic Bevacizumab May Mitigate Radiation Injury: An Experimental Study.

BACKGROUND: Stereotactic radiosurgery (SRS) is widely used to treat brain pathologies alone or in concert with other treatment modalities. However, there are some side effects, such as radiation injury characterized by edema and necrosis in peripheral tissues, that must be managed. A new treatment agent against this side effect is bevacizumab, which targets increased vascular endothelial growth factor (VEGF) as a prominent etiologic factor in radiation injury. In this study, we created a rat experimental model to describe the effects of both radiation and the anti-VEGF monoclonal antibody bevacizumab following high-dose SRS, and to compare the effects of prophylactic and delayed-onset bevacizumab treatment. METHODS: Fifty-four adult male Wistar rats were allocated into 9 groups based on differing Gamma-knife surgery (GKS) doses and bevacizumab treatment protocols. After 12 weeks, the rats' right frontal lobes were examined with hematoxylin and eosin staining and immunohistochemistry analysis via VEGF and CD31 antibodies. RESULTS: Radiation necrosis occurred to varying degrees in all irradiated animals between 3 and 10 weeks post-SRS. Higher GKS dose (50% isodose of 100 Gy) led earlier necrosis and prophylaxis of bevacizumab at this dose was associated with delayed onset of necrosis. Moreover, prophylactic bevacizumab mitigated the effects of radiation necrosis following GKS at both doses, whereas this effect was not prominent with late initiation of bevacizumab (treatment protocol). CONCLUSIONS: Our findings show that the onset and degree of radiation injury are affected by the GKS dose and protocol of bevacizumab administration.

Usefulness of End-to-Side Bridging Anastomosis of Sural Nerve to Tibial Nerve: An Experimental Research.

OBJECTIVE: Repair of sensorial nerve defect is an important issue on peripheric nerve surgery. The aim of the present study was to determine the effects of sensory-motor nerve bridging on the denervated dermatomal area, in rats with sensory nerve defects, using a neural cell adhesion molecule (NCAM). METHODS: We compared the efficacy of end-to-side (ETS) coaptation of the tibial nerve for sural nerve defect repair, in 32 Sprague-Dawley rats. Rats were assigned to 1 of 4 groups: group A was the sham operated group, group B rats had sural nerves sectioned and buried in neighboring muscles, group C experienced nerve sectioning and end-to-end (ETE) anastomosis, and group D had sural nerves sectioned and ETS anastomosis was performed using atibial nerve bridge. Neurological evaluation included the skin pinch test and histological evaluation was performed by assessing NCAM expression in nerve terminals. RESULTS: Rats in the denervated group yielded negative results for the skin pinch tests, while animals in the surgical intervention groups (group C and D) demonstrated positive results. As predicted, there were no positively stained skin specimens in the denervated group (group B); however, the surgery groups demonstrated significant staining. NCAM expression was also significantly higher in the surgery groups. However, the mean NCAM values were not significantly different between group C and group D. CONCLUSION: Previous research indicates that ETE nerve repair is the gold standard for peripheral nerve defect repair. However, ETS repair is an effective alternative method in cases of sensorial nerve defect when ETE repair is not possible.

The time course changes in expression of aquaporin 4 and aquaporin 1 following global cerebral ischemic edema in rat.

BACKGROUND: The aim of this global cerebral ischemia study was to study the changes in expression levels of aquaporin 4 (AQP4) and AQP1 over time. METHODS: Sprague-Dawley type male rats were divided into six groups. Sham group and ischemia/reperfusion were performed on five other groups using the four-vessel occlusion model. Reperfusion was done 30 min after the occlusion, and each group was tested at 1, 6, 12, 24, and 48 h for brain wet-dry weight ratio and AQP4 and AQP1 expression levels using immunohistochemistry. To prove ischemia development exists in both hippocampal neurons and epithelia of choroid plexus, hematoxylin, and eosin and  neuronal marker (NeuN) immune-staining have been applied to the sham experimental group at 48 h. AQP4 expression levels are also measured with western blotting. RESULTS: After ischemia/reperfusion it is observed that the decrease in brain water content between 12 and 24 h was statistically significant (P < 0.01). In parallel and based on immunohistochemical staining, AQP4 expression levels did not exhibit any statistically significant change. AQP4 levels did not show any statistically significant change in western blotting. AQP1 expression in choroid plexus epithelial cells decreased at the 12 and 24 h but increased in 48 h (P < 0.05). CONCLUSIONS: Lack of change in AQP4 expression levels is thought as its dual role in formation and elimination of ischemic brain edema. Decrease in AQP1 expression levels in 24 h can be explained with necrosis in choroid plexus after ischemia and the increase in 48 h mark can be related to recovery in choroid plexus.

Histopathological Analysis of Internal Limiting Membrane Surgically Peeled From Eyes with Epiretinal Membrane.

PURPOSE: To investigate histopathological changes of internal limiting membrane (ILM) in patients with epiretinal membrane (ERM) Materials and Methods: Forty-two eyes of 42 patients who were diagnosed as ERM and enrolled for vitreoretinal surgery were included in this study. Brilliant Blue G (BBG) was used to stain the ILM in all patients. ILM was peeled in all subjects and analyzed by light microscopy (methylene blue-Azur II × 40). ILM samples were then fixed in 2.5% glutaraldehyde solution and examined in JEOL-JEM 1400 and 2100F electron microscope and photographed by CCD camera (Gatan Inc., Pleasanton, CA). RESULTS: Remained ERM fragments were observed on 80% of ILM's. Vacuolization of ILM was observed in a patient with diabetic ERM. There were cells and cellular fragments observed mostly at retinal side of ILM which was likely to be a fragment of Muller cells of retina. CONCLUSIONS: Most of the ILM's had residual ERM tissue and contained cells and cellular fragments at retinal side of ILM's. ILM peeling might have a role in decreasing ERM recurrence by removal of residual ERM tissues.