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Intervertebral disc (IVD) degeneration, a common cause of low back pain in humans, is a relentlessly progressive phenomenon with no currently available effective treatment. In an attempt to solve this dilemma, we transplanted autologous mesenchymal stem cells (MSCs) from bone marrow into a rabbit model of disc degeneration to determine if stem cells could repair degenerated IVDs. LacZ expressing MSCs were transplanted to rabbit L2-L3, L3-L4 and L4-L5 IVDs 2 weeks after induction of degeneration. Changes in disc height by plain radiograph, T2-weighted signal intensity in magnetic resonance imaging (MRI), histology, immunohistochemistry and matrix associated gene expressions were evaluated between normal controls (NC) without operations, sham operated with only disc degeneration being induced, and MSC-transplanted animals for a 24-week period. Results showed that after 24 weeks post-MSC transplantation, degenerated discs of MSC-transplanted group animals regained a disc height value of about 91%, MRI signal intensity of about 81%, compared to NC group discs. On the other hand, sham-operated group discs demonstrated the disc height value of about 67% and MRI signal intensity of about 60%. Macroscopic and histological evaluations confirmed relatively preserved nucleus with circular annulus structure in MSC-transplanted discs compared to indistinct structure seen in sham. Restoration of proteoglycan accumulation in MSC-transplanted discs was suggested from immunohistochemistry and gene expression analysis. These data indicate that transplantation of MSCs effectively led to regeneration of IVDs in a rabbit model of disc degeneration as suggested in our previous pilot study. MSCs may serve as a valuable resource in cell transplantation therapy for degenerative disc disease.  相似文献   
104.
To determine the major antigenic component of Candida albicans against immunoglobulin E (IgE) antibodies in the sera of patients with allergies who were positive for IgE antibodies to C. albicans crude antigen in a CAP system, phosphomannoproteins (CAMP/A or CAMP/B for serotype A or B strain, respectively) and their acid-stable portions (CAMP-S/A or CAMP-S/B) were isolated from beta-mercaptoethanol (2-ME) extracts of C. albicans cells of serotypes A and B, and IgE antibodies against these components were compared with those against protein complex and enolase (CAE) fractions isolated from C. albicans cells. The dot blot test, which was used to detect IgE antibodies to the C. albicans antigens, showed that IgE antibodies to the 2-ME extract and phosphomannoprotein fractions were present in the sera of 98.0% (2-ME extract), 96.8% (CAMP/A), 93.2% (CAMP-S/A), 97.2% (CAMP/B), and 81.5% (CAMP-S/B) of the patients, whereas IgE antibodies to the protein complex and CAE fractions were found in the sera of 73.6 and 48.8% of the patients, respectively. The extent of IgE binding to the 2-ME extract and phosphomannoproteins was well correlated with the fluorescence intensities estimated with the CAP system. Furthermore, the results obtained from the inhibition experiment with the CAP system indicated that the binding of IgE antibodies to Candida antigens is strongly inhibited by the phosphomannoprotein fraction and is an indication that the serum of the patients contained IgE antibodies specific to the cell wall phosphomannoproteins of C. albicans. Finally, an initial chemical analysis indicated that the epitopes for IgE antibodies on the phosphomannoproteins is a carbohydrate portion, since the ability of CAMP/A to inhibit the binding of IgE antibodies to the homologous CAMP/A was destroyed after oxidation by sodium periodate but not after digestion with proteinase K.  相似文献   
105.
We use immunohistochemistry to show the existence of verotoxin receptor in small sensory neurons in DRG of human, rabbit, rat and mouse. In capillary in nervous system, the verotoxin receptor exists in human and rabbit, but the receptor could not be demonstrated in rat and mouse, by this method. The receptors in sensory neuron of rat and in capillary in rabbit brain are determined as galactosylglobotriaosylceramide (GalGb3) and globotriaosylceramide (Gb3,), respectively. Although verotoxin was reported to bind to glycolipid receptors that possess the terminal disaccharide Galalpha1-4Galbeta (galactobiose), the binding to toxin to galabiosylceramide was half of that of GalGb3 which has galactobiose internally.  相似文献   
106.
We present a case of cystic meningioma accompanied by hemorrhage in the cyst and adjacent subarachnoid space that occurred while preoperative embolization in feeders of the tumor was being applied. The possible reason for the hemorrhage was the sudden dynamic changes in blood flow triggered by the embolization. The changes could have caused multiple ruptures of pathologic small vessels. We recommend that preoperative embolization should be used cautiously in treating cystic meningiomas because of a possible increase in bleeding from pathologic weak vessels.  相似文献   
107.
BACKGROUND: We investigated heterotopic hepatocyte transplantation on biodegradable polymers as a potential treatment for end-stage liver disease. The primary problem has been insufficient engraftment of transplanted cells partly because of insufficient vascularization. Increasing vascularization through locally delivered angiogenic factors may increase angiogenesis and hepatocyte engraftment. METHODS: We studied the effect of local delivery of basic fibroblast growth factor (bFGF) on angiogenesis and hepatocyte engraftment within tissue-engineered liver constructs. Poly-l-lactic acid discs were fabricated and coated with either a mixture of saline, sucralfate, and Hydron (control group) or bFGF, sucralfate, and Hydron (bFGF group). bFGF release from polymers in vitro was tested using an ELISA. Hepatocytes were isolated from Lewis rats, seeded on control (n=9) or bFGF (n=11) polymers, and implanted into the small bowel mesentery of syngeneic animals. Specimens were harvested after 2 weeks and analyzed for hepatocyte engraftment. Microvascular density was compared between control (n=6) and bFGF groups (n=5). RESULTS: Three hundred twenty-three thousandths of a microgram of bFGF were incorporated per polymer. Greater than 99% of the bFGF was released into solution by 72 hr in vitro. Two weeks after implantation, microvascular density, as measured by capillaries per high-powered field (c/hpf), was significantly greater in the bFGF group (43.8 c/hpf), compared with the control group (30.5 c/hpf; P<0.005). Specimens from the bFGF group (mean engraftment, 61,355 microm2) showed a 2.5-fold increase in hepatocyte engraftment as compared with control (24,197 microm2; P<0.002). CONCLUSIONS: The angiogenic growth factor bFGF can be incorporated into degradable polymers used as delivery devices for hepatocyte transplantation. Implantation of these devices increases angiogenesis into the device and increases hepatocyte engraftment.  相似文献   
108.
BACKGROUND: Postoperative liver failure is a life-threatening complication after hepatic resection. Because of recent advances in liver surgery technique and a more stringent patient selection, mortality after hepatic resection has steadily decreased, but its incidence still ranges from 10% to 20%. The factors linked to postoperative liver failure in major hepatic resection in the modern era should be reevaluated. STUDY DESIGN: Of 80 patients with viral markers (hepatitis C viral antibody or hepatitis B surface antigen) who underwent major hepatic resections (no less than bisegmentectomies) for hepatocellular carcinoma between 1990 and 1996, 7 patients (8.8%) died of postoperative liver failure within 6 months after hepatectomy. The cause of liver failure was analyzed based on both the preoperative data and the intraoperative findings. In addition, since all the patients who died of liver failure underwent a right hepatic lobectomy, a further data analysis was also done in 47 patients who underwent a right lobectomy of the liver. A volumetric analysis by CT was then done to evaluate the remnant liver volume. RESULTS: Between the patients with liver failure and those without liver failure who underwent a right lobectomy, there were no significant differences in preoperative data or intraoperative findings. Volumetric analysis revealed that the remnant liver volume of patients who died of liver failure was significantly smaller than that of patients who lived (p = 0.008). The incidence of liver failure in patients with a remnant liver volume of less than 250 mL/m2 was 7 of 20 (38%), while it was 0 of 27 in patients with a liver volume of no less than 250 mL/m2 (p = 0.0012). The only significant risk factor for liver failure in patients with a remnant liver volume of less than 250 mL/m2 was diabetes mellitus (p = 0.0072). CONCLUSIONS: The expected remnant liver volume appears to be a good predictor for liver failure in patients who undergo a right lobectomy of the liver. In patients with diabetes mellitus and an expected remnant liver volume of less than 250 mL/m2, a major hepatectomy should be avoided. Careful patient selection based on volumetric analysis in major hepatectomy cases could help prevent the occurrence of postoperative liver failure.  相似文献   
109.

Purpose

Despite the importance of the inhibition of catabolic response to surgery, the effects of different anesthetic techniques on the catabolic response in surgical patients are controversial. This study compared the endocrine-metabolic responses and protein catabolism during gastrectomy in patients who received either sevoflurane or propofol anesthesia with remifentanil.

Methods

Thirty-seven patients (American Society of Anesthesiologists status I–III) aged 20–79 years undergoing elective gastrectomy were randomly assigned to receive sevoflurane anesthesia with remifentanil (n = 19) or intravenous propofol anesthesia (Propofol-Lipuro® 1 %; B. Braun, Melshungen AG, Germany) with remifentanil (n = 18). Urine samples were collected every 1 h after skin incision (0 h) and the urinary 3-methylhistidine:creatinine ratio (3-MH/Cr ratio) was used as a marker of protein catabolism. Respiratory quotient was measured during a 1 h period following skin incision.

Results

The 3-MH/Cr ratio significantly increased at 1–2 and 2–3 h compared to 0 and 0–1 h in both groups, but the propofol group exhibited a lower 3-MH/Cr ratio (nmol/μmol) than the sevoflurane group at 1–2 h (15.7 vs. 18.2, P = 0.012) and 2–3 h (15.9 vs. 18.1, P = 0.025). A difference was observed in the respiratory quotient between the sevoflurane and propofol groups (0.726 vs. 0.707, P = 0.003).

Conclusion

A lower 3-MH/Cr ratio and a lower respiratory quotient during propofol anesthesia, compared to those exhibited during sevoflurane anesthesia, suggest that protein sparing probably occurs through the utilization of medium-chain triglycerides contained in the fat emulsion of propofol solution as a fuel source.  相似文献   
110.
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