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41.
S Simona Jakab Victor J Navarro Beth W Colombe Constantine Daskalakis Steven K Herrine Simona Rossi 《Liver transplantation》2007,13(10):1405-1413
Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease. 相似文献
42.
Klippel-Feil syndrome (KFS) is a heterogeneous entity, characterized by specific congenital anomalies of segmentation of the cervical spine. We report a case of KFS plus atretic meningocele in one identical twin and anencephaly in the other. These identical twins were both male with no chromosome defect. One of them had anencephaly diagnosed at the gestational age of 17 weeks and died soon after birth, whereas the co-twin had KFS with multiple congenital anomalies including short neck with low hairline, occipital atretic meningocele, butterfly vertebrae, hemivertebrae, cervico-thoracic scoliosis, left thumb preaxial polydactyly, and right undescended testis. He received rehabilitation during infancy and could walk at the age of 15 months. Both of these infants had preaxial polydactyly, which is an uncommon anomaly associated with KFS. In conclusion, iniencephaly and anencephaly are probably the extreme manifestations of KFS rather than different dysraphisms. Prompt clinical suspicion with early diagnostic imaging for spine lesions and occult opening of neural tube is mandatory for further intervention and rehabilitation. 相似文献
43.
44.
Christian J. Sauder Cheryl X. Zhang Malen A. Link W. Paul Duprex Kathryn M. Carbone Steven A. Rubin 《Vaccine》2009
The recent global resurgence of mumps has drawn attention to the continued need for robust mumps immunization programs. Unfortunately, some vaccines derived from inadequately attenuated vaccine strains of mumps virus have caused meningitis in vaccinees, leading to withdrawal of certain vaccine strains from the market, public resistance to vaccination, or in some cases, cessation of national mumps vaccination programs. The most widely implicated mumps vaccine in cases of postvaccination meningitis is derived from the Urabe AM9 strain, which remains in use in some countries. The Urabe AM9 vaccine virus has been shown to exhibit a considerable degree of nucleotide and amino acid heterogeneity. Some studies have specifically implicated variants containing a lysine residue at amino acid position 335 in the hemagglutinin-neuraminidase (HN) protein with neurotoxicity, whereas a glutamic acid residue at this position was associated with attenuation. To test this hypothesis we generated two modified Urabe AM9 cDNA clones coding either for a lysine or a glutamic acid at position 335 in the HN gene. The two viruses were rescued by reverse genetics and characterized in vitro and in vivo. Both viruses exhibited similar growth kinetics in neuronal and non-neuronal cell lines and were of similar neurotoxicity when tested in rats, suggesting that amino acid 335 is not a crucial determinant of Urabe AM9 growth or neurovirulence. 相似文献
45.
Histopathological characterisation of effects of the mouse Pax6 missense mutation on eye development
Thaya Ramaesh Steven E. Williams Catriona Paul Kanna Ramaesh John D. West 《Experimental eye research》2009,89(2):263-273
Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6− null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases. 相似文献
46.
Steven D. Wexner MD FACS FRCS FRCS Lester Rosen MD Todd H. Baron MD FASGE 《Gastrointestinal endoscopy》2007,65(7):1104-1105
47.
Sumon Nandi Steven Maschke Peter J. Evans Jeffrey N. Lawton 《Hand (New York, N.Y.)》2009,4(4):368-379
Elbow motion is essential for upper extremity function to position the hand in space. Unfortunately, the elbow joint is prone
to stiffness following a multitude of traumatic and atraumatic etiologies. Elbow stiffness can be diagnosed with a complete
history and physical exam, supplemented with appropriate imaging studies. The stiff elbow is challenging to treat, and thus,
its prevention is of paramount importance. When this approach fails, non-operative followed by operative treatment modalities
should be pursued. Upon initial presentation in those who have minimal contractures of 6-month duration or less, static and
dynamic splinting, serial casting, continuous passive motion, occupational/physical therapy, and manipulation are non-operative
treatment modalities that may be attempted. A stiff elbow that is refractory to non-operative management can be treated surgically,
either arthroscopically or open, to eliminate soft tissue or bony blocks to motion. In the future, efforts to prevent and
treat elbow stiffness may target the basic science mechanisms involved. Our purpose was to review the etiologies, classification,
evaluation, prevention, operative, and non-operative treatment of the stiff elbow. 相似文献
48.
Biostatisticians have frequently uncritically accepted the measurements provided by their medical colleagues engaged in clinical research. Such measures often involve considerable loss of information. Particularly, unfortunate is the widespread use of the so‐called ‘responder analysis’, which may involve not only a loss of information through dichotomization, but also extravagant and unjustified causal inference regarding individual treatment effects at the patient level, and, increasingly, the use of the so‐called number needed to treat scale of measurement. Other problems involve inefficient use of baseline measurements, the use of covariates measured after the start of treatment, the interpretation of titrations and composite response measures. Many of these bad practices are becoming enshrined in the regulatory guidance to the pharmaceutical industry. We consider the losses involved in inappropriate measures and suggest that statisticians should pay more attention to this aspect of their work. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
49.
Steven Z George John D Childs Deydre S Teyhen Samuel S Wu Alison C Wright Jessica L Dugan Michael E Robinson 《BMC musculoskeletal disorders》2007,8(1):92
Background
There are few effective strategies reported for the primary prevention of low back pain (LBP). Core stabilization exercises targeting the deep abdominal and trunk musculature and psychosocial education programs addressing patient beliefs and coping styles represent the current best evidence for secondary prevention of low back pain. However, these programs have not been widely tested to determine if they are effective at preventing the primary onset and/or severity of LBP. The purpose of this cluster randomized clinical trial is to determine if a combined core stabilization exercise and education program is effective in preventing the onset and/or severity of LBP. The effect of the combined program will be compared to three other standard programs. 相似文献50.
Synergistic effect of low dose Cyclosporine A and human interleukin 10 overexpression on acute rejection in rat lung allotransplantation 总被引:3,自引:0,他引:3
Jaroslaw Pierog Amiq Gazdhar Uz Stammberger Matthias Gugger Steven Hyde Iacob Mathiesen Tomasz Grodzki Ralph A. Schmid 《European journal of cardio-thoracic surgery》2005,27(6):1030-1035
Objective: Electroporation mediated transfer of plasmid DNA into peripheral muscle results in high transfection efficiency. The aim of this study was to investigate the effect of gene transfer of human IL-10 (hIL-10) into the tibialis anterior muscle (MTA) in combination with low dose Cyclosporine A (CsA) on acute rejection of lung allografts in the rat. Methods: Lung allotransplantation was performed from male BN donor to male Fisher F344 rats. Gene transfer was achieved by intramuscular injection into the MTA of the recipient followed by electroporation (4×20 ms impulses at 200 V/cm) 24 h prior to the transplantation. Group A (n=5) received CsA (2.5 mg/kg bw ip) for 5 days post-transplant and group B (n=5) 2.5 μg of PCIK hIL-10 (plasmid expression vector containing human CMV immediate early gene promoter and enhancer) and a low dose CsA (2.5 mg/kg bw i.p.). Graft function was assessed by blood gas at day 5 after exclusion of the native lung. Animals were sacrificed and blood was drawn to measure serum hIL-10 levels (ELISA) and tissue was sampled for histological grading of rejection. Results: Local expression of hIL-10 was confirmed at the mRNA level by in situ hybridization. All group A control animals showed severe signs of rejection. At day 5 all grafts in group B showed good gas exchange mean PaO2 233±123 mmHg, vs 44±8 mmHg in group A. Histological examination revealed moderate to severe rejection in all animals in group A (IIIB, ISHLT) in contrast to low moderate rejection in group B (II–IIIA). hIL-10 serum levels on day 5 were 14±7 pg/ml in group B vs. 0 in group A. Conclusions: Electroporation mediated hIL-10 overexpression in a peripheral muscle of the recipient in combination with low dose CsA reduces acute rejection in this model of rat lung allotransplantation. 相似文献