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911.
Köseoğlu B Yilmaz E Ceylan K Uzun E Bayram I Hizli F 《International urology and nephrology》2009,41(1):85-91
Introduction The aim of the present study was to evaluate the effects of erythropoietin (EPO) on the histopathology of testes after unilateral
testicular torsion and detorsion.
Materials and methods Twenty-five male Sprague–Dawley rats weighing 120 g were used in this study. The rats were randomly divided into three groups,
a sham group consisting of five rats and the other two groups consisting of ten rats. In group 1 (sham group), right orchiectomy
with no additional intervention was performed. In group 2 (T/D group), torsion was created by rotating the testis 720° in
a clockwise direction for 4 h. After a 4-h torsion period, the right testis was detorted and replaced into the scrotum for
4 h. After the torsion, 0.5 cc 0.9% NaCl solution was injected once and three times in a week (total 12 doses). In group 3
(T/D + erythropoietin; EPO group), the same surgical procedure was done as in group 1, but EPO 1,000 IU/kg was injected just
before the detorsion and three times in a week. At the end of each procedure, bilateral orchiectomies were performed for the
histopathological examinations in all groups.
Results We examined the testes weight, vascularization of the region between the seminiferous tubules, percentage of necrotic seminipherous
tubules, and maturation of spermatogenesis in terms of necrosis, sertoli cells, maturation arrest of spermatogenesis, hypospermatogenesis,
and normal spermatogenesis of torsioned testis tissues with and without EPO treatment. Extremely significant differences in
testicular weight were observed in group 1 compared to groups 2 and 3 (P < 0.001).
Conclusion Administration of EPO significantly influenced the rescue of testicular function by preserving the intact seminiferous tubular
morphology, lowering the percentage of necrotic seminipherous tubules, and significantly reducing histological damage (P < 0.05). 相似文献
912.
Dokucu AI Ozturk H Ozturk H Tuncer MC Yilmaz F 《International urology and nephrology》2009,41(1):101-108
This study was designed to determine the effect of molsidomine (MO), a precursor of nitric oxide (NO) donor, on hypoxia inducible
factor alpha (HIF-1α) and Sonic hedgehog (Shh) levels considered to be involved in the development of testes ischemia/reperfusion
(I-R) injury. Torsions were created by rotating ipsilateral testes 720° in a clockwise direction for 6 h and 1-h detorsion
of the testis was performed. A sham operation was performed in group 1 (control, n = 7). In group 2 (I-R/Untreated, n = 7), following 6 h of unilateral testicular torsion, 1-h detorsion of the testis was performed. No drug was given. In group
3 (I-R/MO), after performing the same surgical procedure as in group 2, a NO donor MO was given at the starting time of reperfusion.
In group 4 (I-R/L-NAME), after performing the same surgical procedure as in group 2, L-NAME was given at the starting time
of reperfusion. Testes malondialdehyde (MDA) levels were determined as well as examining the testes histologically. Treatment
of rats with MO produced a significant reduction in the levels of MDA and histopathological score compared to testes I-R groups.
The Sonic hedgehog (Shh) expression in the basement membrane of the tubuli seminiferi, and sertoli and germinal cells in testicular
tissue, were greatly increased in the I-R/MO group compared to groups 1, 2 and 4. Additionally, the HIF-1α expression in the
interstitial spaces in testicular tissue were greatly increased in the I-R/MO group. The results suggest that MO has a protective
effect against ischemia/reperfusion injury in rat testes and may affect Shh and HIF-1α signaling pathway. 相似文献
913.
Satoru Motoyama Kiyotomi Maruyama Yusuke Sato Shuetsu Usami Toshinobu Nakatsu Hajime Saito Yoshihiro Minamiya Jun-ichi Ogawa 《World journal of surgery》2009,33(3):512-517
Background Three-field lymph node dissection for thoracic esophageal cancer is associated with high morbidity and reduced quality of
life after surgery. Consequently, minimized lymphadenectomy would be desirable, if appropriate. In the present study, we retrospectively
analyzed the status of involved nodes and the direction of metastatic lymphatic flow from tumors into involved nodes to determine
whether submucosal squamous cell esophageal cancers are potential candidates for minimized lymphadenectomy.
Methods We enrolled 199 patients who received esophagectomy with extensive lymph node dissection between 1989 and 2005 and retrospectively
analyzed their prognoses, distribution of solitary metastatic lymph nodes, and the direction of metastatic lymphatic flow
from the tumor, taking into consideration tumor location and depth.
Results Of these patients with submucosal cancers, 83% had 1 or 2 involved nodes, and their esophageal cancer-specific 5-year survival
rate was 66%. Solitary lymph node metastasis did not occur in neck lymph nodes in lower thoracic submucosal esophageal cancers,
and the direction of metastatic lymphatic flow from the tumor was almost always in one direction. By contrast, T2–4 cancers
with 2–4 involved nodes had bidirectional metastatic lymphatic flow from the tumor.
Conclusions There was a difference in the status of lymph node metastasis and the direction of metastatic lymphatic flow from tumors into
involved nodes between submucosal and T2–4 thoracic squamous cell esophageal cancers. This analysis may be useful for developing
an approach to minimized lymphadenectomy for thoracic esophageal cancers. 相似文献
914.
Kim JG Ha JG Lee YS Yang SJ Jung JE Oh SJ 《Archives of orthopaedic and trauma surgery》2009,129(3):381-385
This paper reports a novel method for reconstructing the posterolateral structures [lateral collateral ligament (LCL), popliteus
tendon, popliteofibular ligament] based on an anatomical study of a cadaveric dissection. The popliteus tendon was found to
always be attached to the anterior–inferior portion of the femoral attachment site of the LCL, and the average distance from
the origin of the popliteal tendon in the femoral side to that of the LCL was 18.5 mm (17–20). The insertion site of the LCL
in the fibular side was located anterior–inferior-superficially and the popliteofibular ligament was inserted into the posterior–superior-deep
portion around the styloid process. Two femoral tunnels and one fibular head tunnel were made at the proximal and distal portion
of the anatomical insertion sites. 相似文献
915.
Diermann N Schumacher T Schanz S Raschke MJ Petersen W Zantop T 《Archives of orthopaedic and trauma surgery》2009,129(3):353-358
Introduction Recently, several publications investigated the rotational instability of the human knee joint under pivot shift examinations
and reported the internal tibial rotation as measurement for instrumented knee laxity measurements. We hypothesize that ACL
deficiency leads to increased internal tibial rotation under a simulated pivot shift test. Furthermore, it was hypothesized
that anatomic single bundle ACL reconstruction significantly reduces the internal tibial rotation under a simulated pivot
shift test when compared to the ACL-deficient knee.
Methods In seven human cadaveric knees, the kinematics of the intact knee, ACL-deficient knee, and anatomic single bundle ACL reconstructed
knee were determined in response to a 134 N anterior tibial load and a combined rotatory load of 10 N m valgus and 4 N m internal
tibial rotation using a robotic/UFS testing system. Statistical analyses were performed using a two-way ANOVA test.
Results Single bundle ACL reconstruction reduced the anterior tibial translation under a simulated KT-1000 test significantly compared
to the ACL-deficient knee (P < 0.05). After reconstruction, there was a statistical significant difference to the intact knee at 30° of knee flexion.
Under a simulated pivot shift test, anatomic single bundle ACL reconstruction could restore the intact knee kinematics. Internal
tibial rotation under a simulated pivot shift showed no significant difference in the ACL-intact, ACL-deficient and ACL-reconstructed
knee.
Conclusion In conclusion, ACL deficiency does not increase the internal tibial rotation under a simulated pivot shift test. For objective
measurements of the rotational instability of the knee using instrumented knee laxity devices under pivot shift mechanisms,
the anterior tibial translation should be rather evaluated than the internal tibial rotation.
This study was supported in part by a grant of the German Speaking Association of Arthroscopy (AGA). 相似文献
916.
Background Patients with pancreatic tumors that induce hypoglycemia present with a myriad of symptoms. Laboratory testing can frequently
result in data challenging to the clinician to confirm the biochemical diagnosis. Proinsulin, in addition to insulin levels,
may be essential in evaluating and diagnosing an insulinoma.
Methods The objective of this case report is to demonstrate the potential importance of proinsulin levels in the evaluation of tumor-induced
hypoglycemia. We report a 49-year-old woman with an unusual clinical presentation. Unlike many patients with tumor-induced
hypoglycemia, her fasting glucose levels were fairly unimpressive, her insulin levels were undetectable during a prolonged
fast, and she had elevated proinsulin levels.
Results The inpatient fast was remarkable for levels of serum glucose 53 mg/dl or higher, a serum insulin <2 uIU/ml, C-peptide 0.7–1.1
(nl 0.8–3.1 ng/ml), and proinsulin 29.2–36.8 pmol/l (nl ≤ 18.8 pmol/l). CT scanning of the abdomen revealed multiple pancreatic
lesions. A laparoscopic distal pancreatectomy led to the removal of multiple neuroendocrine tumors, which stained only for
proinsulin and not for other pancreatic tumor markers. Postoperatively, she normalized her biochemical serum studies and has
remained symptom-free 2 years later.
Conclusions The measurement of proinsulin plays an important part in the diagnostic workup of neuroendocrine tumors causing hypoglycemia.
These potentially malignant tumors can be treated adequately with minimally invasive surgery. 相似文献
917.
Sehirlioglu A Ozturk C Yazicioglu K Tugcu I Yilmaz B Goktepe AS 《International orthopaedics》2009,33(2):533-536
This article reports an analysis of 75 consecutive lower limb amputees who developed painful neuroma requiring surgical excision after lower limb amputation following landmine explosions. This retrospective study analyses the results of 75 patients who were treated for painful neuroma after lower limb amputation following landmine explosions between the years 2000 and 2006. The average time period from use of prosthesis to start of symptoms suggesting neuroma was 9.6 months. The average time period from start of pain symptoms to neuroma surgery was 7.8 months. All clinically proven neuromas were surgically resected. In the mean follow-up of 2.8 years, all patients were satisfied with the end results and all were free of any pain symptoms. Painful stump with clinical diagnostic findings of neuroma described above may be regarded as neuroma without requiring any further imaging modalities and is an indication for surgery if conservative measures fail. 相似文献
918.
Kentaro Mitsuka Toru Horikoshi Arata Watanabe Hiroyuki Kinouchi 《Acta neurochirurgica》2009,151(1):85-88
Summary The diagnosis of tethered cord syndrome (TCS) without typical conus medullaris symptoms and the radiological features such
as a low set conus medullaris or dysraphic malformation is difficult. We report 11 year old identical twin brothers with TCS
associated with the conus at the normal level. Their presenting symptom was progressive leg pain and both patients underwent
surgical interruption of the filum terminale. The pain recurred in one patient treated surgically only after symptom became
worse but resolved immediately in the other sibling treated promptly. We indicate the importance of early diagnosis and treatment
of TCS to obtain excellent long-term outcome despite the absence of a low set conus or specific symptoms. Furthermore, when
a twin or sibling of an affected person has neurological symptoms and the cutaneous signature of spinal dysraphism, radiological
examination should be performed to establish the cause. 相似文献
919.
Kazushi Takayama Akinobu Suzuki Tomoya Manaka Susumu Taguchi Yusuke Hashimoto Yuuki Imai Shigeyuki Wakitani Kunio Takaoka 《Journal of bone and mineral metabolism》2009,27(4):402-411
Noggin is a major extracellular antagonist to bone morphogenetic proteins (BMPs) which binds to BMPs and blocks binding of
them to BMP-specific receptors and negatively regulates BMP-induced osteoblastic differentiation. In this study, we investigated
the effect of noggin silencing by transfection of small interfering RNA (siRNA) on BMP-induced osteoblastic differentiation
in vitro and ectopic bone formation in vivo induced by recombinant human BMP-2 (rhBMP-2). Noggin mRNA expression was up-regulated
in response to rhBMP-2 in C2C12 cells, a myoblastic cell line, in dose- and time-dependent fashion as determined by real-time
RT-PCR assay. Silencing of noggin expression by transfection of noggin siRNA suppressed BMP-stimulated noggin expression,
resulting in acceleration of BMP-induced osteoblastic differentiation. For in vivo noggin silencing, siRNA was injected locally
into back muscles and transfected into local cells by electroporation, where rhBMP-2-retaining (5 μg) collagen disks had been
surgically placed. The implants were harvested at 2 weeks after surgery from experimental and control group mice and analyzed
by radiological and histological methods. As a result, bone mineral content of ossicles ectopically induced by rhBMP-2 was
significantly increased by silencing of noggin. Our findings suggest that silencing of noggin enhances the osteoblastic differentiation
of BMP-responding cells in vitro and new bone formation induced by rhBMP-2 in vivo by eliminating negative regulation of the
effects of BMP. RNA interference might be useful for intensifying the effects of BMP in promoting new bone (callus) formation
in repair of damaged bone. 相似文献
920.
Gunter Spahn H. Michael Klinger Gunther O. Hofmann 《Archives of orthopaedic and trauma surgery》2009,129(8):1117-1121
Aim In general, arthroscopy is considered the “gold standard” for the evaluation of cartilage lesions. In this multicenter survey,
we ascertained the general opinion of surgeons regarding arthroscopic cartilage diagnoses.
Method A total of 301 highly experienced arthroscopists (instructors of the AGA, the German-speaking society of arthroscopy) were
contacted in writing with a request to complete the survey.
Results The data from 105 respondents (34.8% of those contacted) were used for the investigation. In the grading of the cartilage
lesions, the Outerbridge classification was most frequently used (n = 87), followed by the ICRS protocol (n = 8) and the Insall score (n = 3). The majority (61%) of the arthroscopic surgeons felt that differentiation between healthy cartilage and low-grade cartilage
lesions was simple. For differentiation between grade I and grade II lesions, and for differentiation between grade II and
grade III lesions, 41.9 and 51.4%, respectively, thought that there was a “need for improvement”. In the case of grade IV
lesions, 70.5% of the surgeons thought that the diagnosis was valid. The respondents also judged the utility of incorporating
objective measurements (e.g., intraoperative biomechanical tests): 13.3% (n = 14) responded that such measurements would be “very useful” and 61.9% (n = 65) responded that they would be “somewhat useful”.
Conclusions Among surgeons, arthroscopy was not perceived to be as reliable as a “gold standard” for the diagnosis of cartilage lesions.
The majority of experienced arthroscopists felt unsure of the results in general, or at least in some cases. A universal and
definitive grading system for lesions appears to be needed. For questionable cases, measurement devices are needed for objective
cartilage grading. 相似文献