Young porcine endocrine pancreatic islets cultured in fibrin show improved resistance toward hydrogen peroxide

Aim: To study the protective effect of a fibrin scaffold toward embedded young porcine endocrine pancreatic islets from hydrogen peroxide within the context of islet encapsulation in transplantation. Methods: After isolation and in vitro maturation, groups of 200 young porcine islet equivalents (IEQ) were embedded in a 200 µL fibrin gel and exposed to 2 concentrations (10 and 100 µM) of hydrogen peroxide (H₂O₂) to investigate the ability of fibrin to protect islets against apoptotic stimuli. As a control, young porcine islets were seeded in tissue culture polystyrene (TCPS) well plates and exposed to the same H₂O₂ concentrations. Islet integrity, viability and function were then investigated. Results: Morphologically, the integrity of islets embedded in fibrin gels was better preserved compared with that of islets cultured in TCPS plates, when exposed to H₂O₂. Immunofluorescence staining showed that insulin and glucagon expression was higher in islets cultured in fibrin. Overall, H₂O₂ incubation led to decreased insulin and glucagon expression. A TUNEL assay revealed elevated numbers of apoptotic cells for islets cultured in TCPS plates when compared with those embedded in fibrin. Islets cultured in TCPS plates and exposed to H₂O₂ had diminished ability to secrete insulin in response to glucose stimulation, whereas islets embedded in fibrin maintained their glucose responsiveness. Insulin trapped in fibrin was extracted and quantified, revealing insulin in the extract. Conclusions/Interpretation: Fibrin has a protective effect on young porcine endocrine pancreatic islets exposed to hydrogen peroxide.     

Reimplantation of an Amputated Hand: Long-term Follow-up Report

A case of nearly total amputation of the right hand is described. The hand was reimplanted with initially good result. A final evaluation of the hand was attempted 6 years following the accident. It is concluded that the unsatisfactory nerve regeneration renders the final result a function failure. However, the psychological and cosmetic effect of a real hand may justify the reimplantation.     

Treatment of transected peripheral nerves with artemin improved motor neuron regeneration,but did not reduce nerve injury-induced pain behaviour

Incomplete recovery of function and neuropathic pain are common problems after peripheral nerve injury. To develop new treatment strategies for peripheral nerve injuries we investigated whether the neurotrophic factor artemin could improve outcome after sciatic nerve injuries in rats. Artemin is a member of the glial cell line-derived neurotrophic factor (GDNF) family and exerts neuroprotective effects on sensory neurons as well as influencing behavioural thermal sensitivity. We additionally evaluated if fibrin sealant, which is sometimes used as a nerve glue, had any effects on neuropathic pain-related behaviour. After the sciatic nerve had been transected, 30 animals were randomised to one of three groups: treatment with a fibrin sealant that contained artemin in conjunction with sutures; fibrin sealant with no artemin (sham) in conjunction with sutures; or sutures alone (n=10 in each group). Motor function, sensory function, and autotomy were evaluated from 1 to 12 weeks after injury. Retrograde flourogold tracing 12 weeks after injury showed that the addition of artemin increased the number of regenerating motor neurons. However, it did not improve their performance, as measured by the Sciatic Function Index, compared with sham or suture alone. Animals treated with artemin had a non-significant increase in motor nerve conduction velocity compared with sham. However, artemin did not reverse nerve injury-induced pain behaviour such as cold or heat hypersensitivity. Fibrin sealant in itself did not ameliorate motor performance, or regeneration of motor neurons, or give rise to nerve injury-induced pain behaviour. The results indicate that artemin is of value as a treatment for peripheral nerve injuries, although the effects were limited. As the artemin high-affinity receptor GFRα-3 is present in Schwann cells and not in motor neurons, the effect on motor neuron axon regeneration may result from an indirect effect through Schwann cells in the injured nerve.     

清麴酱激酶的溶栓活性可减轻栓塞性脑梗死后脑损伤

Cheonggukjang is a soybean paste made by fermenting whole cooked soybean with Bacillus subtilis. Cheonggukjang contains a fibrinolytic enzyme that may have clinical applications in removing blood clots. In this study, we use the term “cheonggukjang kinase” (CGK) to refer to this fibrinolytic enzyme. We used fibrin clot lysis and platelet-rich clot lysis assays to clarify the mechanisms by which CGK exerts thrombolytic effects, and, specifically, whether it acts more like a plasminogen activator or like plasmin. Additionally, we examined the thrombolytic effects of CGK in a rat model of cerebral embolic stroke produced by middle cerebral artery occlusion (MCAO) with respect to infarct volume and behavioral performance. In both the fibrin clot lysis and platelet-rich clot lysis assays, the thrombolytic activity was highest in CGK that had been cultured for 40 h. Furthermore, T50%, the time needed to decompose half the clot, did not differ in the presence or absence of plasminogen, indicating that CGK is a plasmin-like protein, not a plasminogen activator. In the rat model of cerebral embolic stroke, clots were no longer visible in rats that received an intravenous infusion of CGK (1 U plasmin-like activity/100 μg CGK/kg) 1 h after MCAO. CGK-treated groups showed a significant dose-dependent reduction in infarct volume. Treatment with CGK also improved functional recovery, as assessed by neurological deficit scores. Reduction of infarct volume and improvement in functional recovery after CGK treatment (1 U plasmin-like activity/100 μg CGK/kg) was greater than after treatment with recombinant tissue plasminogen activator (r-tPA; 10 mg/kg). These data suggest that CGK is an effective agent for reducing infarct volume and improving functional recovery following ischemic brain injury. Moreover, CGK may be a more efficacious clot-dissolving agent than r-tPA. CGK has a number of potential clinical applications in the treatment of stroke.     

Bilateral Sinus Elevation Evaluating Plasma Rich in Growth Factors Technology: A Report of Five Cases

Purpose: The purpose of this study was to evaluate the potential effects of plasma rich in growth factors (PRGF) technology and its autologous formulations in five consecutive patients in which bilateral sinus lift augmentation was carried out. Material and Methods: Five consecutive patients received bilateral sinus floor augmentation. All patients presented a residual bone height of class D (1–3 mm). The effects of PRGF combined with bovine anorganic bone (one side) were compared with the biomaterial alone (contralateral side). The effects of using liquid PRGF to maintain the bone window and autologous fibrin membrane to seal the defect were evaluated. A complete histological and histomorphometrical analysis was performed 5 months after surgery. Results: One patient was excluded from the study as the Schneiderian membrane of the control side was perforated during the surgery. In two patients, the biopsies obtained from the control sides 5 months postsurgery were not acceptable for processing. PRGF technology facilitated the surgical approach of sinus floor elevation. The control area was more inflamed than the area treated with PRGF technology. Patients referred also to an increased sensation of pain in the control area. PRGF‐treated samples had more new vital bone than controls. In patient number 1, image processing revealed 21.4% new vital bone in the PRGF area versus 8.4% in the control area, whereas in patient number 2, 28.4% new vital bone was quantified in the PRGF area compared with the 8.2% of the control side. The immunohistochemical processing of the biopsies revealed that the number of blood vessels per square millimeter of connective tissue was 116 vessels in the PRGF sample versus 7 in the control biopsy. Conclusions: These preliminary results suggest that from a practical point of view, PRGF may present a role in reducing tissue inflammation after surgery, increasing new bone formation and promoting the vascularization of bone tissue.     

Human bone marrow stroma stem cell distribution in calcium carbonate scaffolds using two different seeding methods

Objective: The aim of this study was to develop a method for the determination of the three‐dimensional (3D) distribution of cells in mineralized scaffolds and to compare the effect of two different methods of cell seeding of human bone marrow stroma cells (hBMSCs) in long‐term cultures. Materials and methods: hBMSCs were seeded into CaCO₃ scaffolds by droplet seeding using culture medium with and without the addition of fibrin. After 2, 7, 14, and 21 days of culture, the constructs were embedded into methylmethacrylate and serially sectioned using undecalcified thick section technology. Sections were serially scanned from the surface to the bottom of the scaffolds and DAPI‐stained cells were automatically counted in each section using structured illumination fluorescence microscopy (FM) with serial optical sectioning and image analysis software. Results: The data showed that the seeding efficiency was significantly higher in the scaffolds seeded with the addition of fibrin. Moreover, the number of cells increased to higher levels and remained higher for longer periods with the use of the fibrin matrix, whereas cells seeded in the medium suspension exhibited a sharp decrease after the first week of cultivation. There were distinct differences in the 3D cell distribution between the center and the periphery of the scaffolds. The use of a fibrin matrix was associated with a more uniform cell distribution 1 and 2 weeks after seeding in different levels (center vs. periphery: P>0.05), whereas cells in the medium solution group accumulated at the periphery of the scaffolds. Conclusions: In conclusion, automated serial optical sectioning using structured illumination FM can assess cell numbers and the 3D distribution of hBMSCs in mineralized scaffolds. This allows for a detailed analysis of the effect of different in vitro procedures used for cell seeding. The use of fibrin during seeding increases seeding efficiency and enhances both proliferation and cell survival in the central parts of the scaffolds. To cite this article:
Zhu H, Schulz J, Schliephake H. Human bone marrow stroma stem cell distribution in calcium carbonate scaffolds using two different seeding methods.
Clin. Oral Impl. Res. 21 , 2010; 182–188.
doi: 10.1111/j.1600‐0501.2009.01816.x     

Injectable platelet-rich fibrin as treatment for temporomandibular joint osteoarthritis: A randomized controlled clinical trial

The purpose of this study was to assess the treatment outcomes of intraarticular injection of injectable platelet-rich fibrin (i-PRF) after arthrocentesis in patients with temporomandibular joint osteoarthritis (TMJ-OA). Patients were randomly assigned to one of two treatment groups: those who received intraarticular injection of i-PRF after arthrocentesis procedure – the i-PRF group; and those who underwent the arthrocentesis procedure alone – the control group. The primary outcome variable was pain, the level of which was measured preoperatively and at 1, 2, 3, 6, and 12 months postoperatively. The secondary outcome variables included maximum mouth opening (MMO), and lateral and protrusive movements. Of the total of 36 patients, 18 were analyzed in the i-PRF group and 18 in the control group. There were significant differences between the groups in terms of pain levels and measurements of MMO, lateral movement, and protrusive movement over the 12 months of follow-up (p < 0.001). Significant increases in pain levels and decreases in measurements of MMO, lateral movement, and protrusive movement were observed in the control group from the 6th to 12th month postoperatively (p < 0.001). In contrast, no significant differences were found in both pain levels and measurements of MMO, lateral, and protrusive movements for the i-PRF group from the 2nd to the 12th month postoperatively. Within the limitations of the study it seems that intraarticular injection of i-PRF after arthrocentesis should be preferred whenever appropriate because when reducing pain intensity and improving functional jaw movement is the priority.     

生物蛋白胶宫颈封堵术治疗早产胎膜早破的可行性分析

目的 探讨生物蛋白胶封堵宫颈治疗妊娠未足月胎膜早破延长孕周的意义及可行性.方法 收集我院2006年6月～2007年12月妊娠28～35周胎膜早破患者33例,分成2组,治疗组13例采用生物蛋白胶封堵宫颈治疗,对照组20例采用期待疗法,比较两者的保胎时间长短.结果 治疗组较对照组孕周延长,差异有统计学意义(P＜0.05).结论 未足月胎膜早破患者采用生物蛋白胶封堵宫颈可适当延长孕周.     

Bleeding symptoms and coagulation abnormalities in 337 patients with AL-amyloidosis

Haemorrhage is a frequent manifestation of amyloidosis. We performed a retrospective clinical analysis of 337 patients with systemic immunoglobulin light-chain (AL)-amyloidosis, in whom whole-body serum amyloid P component (SAP) scintigraphy and a clotting screen had been performed. Abnormal bleeding was noted in 94 cases (28%), and the coagulation screen was abnormal in 172 cases (51%). The most common abnormalities were prolongation of the thrombin time (TT; 108 cases, 32%) and the prothrombin time (PT; 82 cases, 24%). In multivariate analysis, a prolonged PT was the only coagulation abnormality associated with abnormal bleeding (P = 0.0012), but this was independent of the whole-body amyloid load. Prolongation of the TT was associated with hepatic amyloid infiltration (P < 0.00001), with proteinuria (P < 0.001) and low serum albumin (P < 0.00001). In 154 patients who were studied further, subnormal factor X activity (FX:C) was found in 22 cases (14%). In cases with subnormal FX:C, the corresponding factor X antigen (FX:Ag) measurements were consistently higher (median FX:Ag/FX:C 2.5, range 0.81-9.25, n = 16) than cases with normal FX:C (median FX:Ag/FX:C 0.96, range 0.65-1.29, n = 28, P < 0.0001). No evidence was found of an FX inhibitor. Of the 48/154 (31%) cases with a prolonged TT, the reptilase time was also prolonged in 38/48 cases (79%). These data show that haemorrhage and abnormal coagulation are common in AL-amyloidosis and are multifactorial in origin. We provide evidence suggesting that hepatic amyloid infiltration and nephrotic syndrome are determinants of the TT. In most patients, prolongation of the PT was explained by reduction in FX:C, but this was not wholly explained by a reduction in FX:Ag.