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Heiko Koller Rene Schmidt Michael Mayer Wolfgang Hitzl Juliane Zenner Stefan Middendorf Nicolaus Gräf H. Resch Hans-Joachim Willke 《European spine journal》2010,19(12):2137-2148
Clinical studies reported frequent failure with anterior instrumented multilevel cervical corpectomies. Hence, posterior augmentation
was recommended but necessitates a second approach. Thus, an author group evaluated the feasibility, pull-out characteristics,
and accuracy of anterior transpedicular screw (ATPS) fixation. Although first success with clinical application of ATPS has
already been reported, no data exist on biomechanical characteristics of an ATPS-plate system enabling transpedicular end-level
fixation in advanced instabilities. Therefore, we evaluated biomechanical qualities of an ATPS prototype C4–C7 for reduction
of range of motion (ROM) and primary stability in a non-destructive setup among five constructs: anterior plate, posterior
all-lateral mass screw construct, posterior construct with lateral mass screws C5 + C6 and end-level fixation using pedicle
screws unilaterally or bilaterally, and a 360° construct. 12 human spines C3–T1 were divided into two groups. Four constructs
were tested in group 1 and three in group 2; the ATPS prototypes were tested in both groups. Specimens were subjected to flexibility
test in a spine motion tester at intact state and after 2-level corpectomy C5–C6 with subsequent reconstruction using a distractable
cage and one of the osteosynthesis mentioned above. ROM in flexion–extension, axial rotation, and lateral bending was reported
as normalized values. All instrumentations but the anterior plate showed significant reduction of ROM for all directions compared
to the intact state. The 360° construct outperformed all others in terms of reducing ROM. While there were no significant
differences between the 360° and posterior constructs in flexion–extension and lateral bending, the 360° constructs were significantly
more stable in axial rotation. Concerning primary stability of ATPS prototypes, there were no significant differences compared
to posterior-only constructs in flexion–extension and axial rotation. The 360° construct showed significant differences to
the ATPS prototypes in flexion–extension, while no significant differences existed in axial rotation. But in lateral bending,
the ATPS prototype and the anterior plate performed significantly worse than the posterior constructs. ATPS was shown to confer
increased primary stability compared to the anterior plate in flexion–extension and axial rotation with the latter yielding
significance. We showed that primary stability after 2-level corpectomy reconstruction using ATPS prototypes compared favorably
to posterior systems and superior to anterior plates. From the biomechanical point, the 360° instrumentation was shown the
most efficient for reconstruction of 2-level corpectomies. Further studies will elucidate whether fatigue testing will enhance
the benefit of transpedicular anchorage with posterior constructs and ATPS. 相似文献
23.
X-linked chronic granulomatous disease: correction of NADPH oxidase defect by retrovirus-mediated expression of gp91-phox 总被引:3,自引:0,他引:3
Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease. 相似文献
24.
Yasar Kucukardali Oral Oncul Saban Cavuslu Mehmet Danaci Semra Calangu Hakan Erdem Ayse Willke Topcu Zuhal Adibelli Murat Akova Emel Azak Karaali Ahmet Melih Ozel Zahit Bolaman Bulent Caka Birsen Cetin Erkan Coban Oguz Karabay Cagla Karakoc Mehmet Akif Karan Selda Korkmaz Gulsen Ozkaya Sahin Alaaddin Pahsa Fatma Sirmatel Emrullah Solmazgul Namik Ozmen Ilyas Tokatli Cengiz Uzun Gulsen Yakupoglu Bulent Ahmet Besirbellioglu Hanefi Cem Gul 《International journal of infectious diseases》2008,12(1):71-79
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies. 相似文献
25.
Moderation of hemophilia A phenotype by the factor V R506Q mutation 总被引:11,自引:1,他引:11
Nichols WC; Amano K; Cacheris PM; Figueiredo MS; Michaelides K; Schwaab R; Hoyer L; Kaufman RJ; Ginsburg D 《Blood》1996,88(4):1183-1187
Although many examples of unrelated hemophilia A patients carrying identical point mutations in the factor VIII (FVIII) gene have been reported, the clinical phenotype is not always the same among patients sharing the same molecular defect. Possible explanations for this discrepancy include undetected additional mutations in the FVIII gene or coinheritance of mutations at other genetic loci that modulate FVIII function. We report molecular genetic analysis of potential modifying genes in two sets of unrelated patients carrying common FVIII missense mutations but exhibiting different levels of clinical severity. Both mutations (FVIII R1689C and R2209Q) are associated with severe hemophilia A in some patients and mild/moderate disease in others. The common von Willebrand disease type 2N mutation (R91Q) was excluded as a modifying factor in these groups of patients. However, analysis of the recently described factor V (FV) R506Q mutation (leading to activated protein C resistance) identified a correlation of inheritance of this defect with reduced hemophilia A severity. Two moderately affected hemophilia A patients, each with either of two FVIII gene mutations, were heterozygous for FV R506Q, whereas two severely affected patients and two moderately affected patients were homozygous normal at the FV locus. Our results suggest that coinheritance of the FV R506Q mutation may be an important determinant of clinical phenotype in hemophilia A and that modification of the protein C pathway may offer a new strategy for the treatment of FVIII deficiency. 相似文献
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The focus on quality of life issues in wound care has justly taken a far greater importance. With the acceptance that pain can be a major factor to the patient, and in particular, pain at dressing change comes the opportunity for avoidance and/or reduction strategies. Whilst pain has been associated with wound infection for millennia, it is only much more recently that this has received due attention from research and clinical practice. In this study, the nature of pain, changes in pain and pain associated with infection are the focal points. A Delphi approach, now a frequently used tool in wound care research, has been used to obtain expert opinion on these aspects of management. 相似文献
29.
Background: Advantages of cross‐pin retained implant supported restorations (ISRs) include predictable retrieval and predictable retention. Unlike direct to fixture (DTF) or cement retained restorations, the prosthetic design of a cross‐pinned restoration retains gaps at the interfaces between the crown, abutment and cross‐pin screw. These spaces permit leakage into the suprastructure and gasket placement has been recommended to prevent this leakage. Methods: Five different gaskets were assessed for their ability to prevent leakage into a cross‐pinned ISR. The gaskets tested were: cement admixture on the cross‐pin screw; cement admixture on the inner surface of the coping and the cross‐pin screw; cement admixture on the inner surface of the coping only; cement admixture placed 1 mm from the margin of the coping and a filler placed in the abutment chimney. Results: Only gaskets which sealed both the cross‐pin screw interface and the abutment‐crown interface prevented leakage. A filler placed in the abutment chimney prevented leakage into this space but did not prevent fluid accumulating between the coping and abutment. Conservative placement of cement at the margin of the coping failed to prevent leakage. Conclusions: Cement gaskets may effectively prevent leakage into a cross‐pinned ISR. However, the use of a cement as a gasket has to be weighed against the issue of predictable retrieval, cement extrusion and incomplete seating. 相似文献
30.