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991.
Cristina Vincent Masakazu Kogawa David M. Findlay Gerald J. Atkins 《Journal of bone and mineral metabolism》2009,27(1):114-119
Osteoclasts are the unique cell type capable of resorbing bone. The discovery of the TNF-ligand family member, RANKL, has
allowed more reliable study of these important cells. The mouse monocytic cell line, RAW 264.7, has been shown to readily
differentiate into osteoclasts upon exposure to recombinant RANKL. Unlike primary osteoclast precursors, there is no requirement
for the addition of macrophage colony stimulating factor (M-CSF). However, to date, their differentiation has always been
studied in the context of added foetal calf serum (FCS). FCS is a complex and largely undefined mixture of growth factors
and matrix proteins, and varies between batches. For this reason, osteoclastogenesis would ideally be studied in the context
of a defined, serum-free medium. RAW 264.7 cells were cultured in serum-replete α-MEM or serum-deprived medium (SDM) shown
previously to support the growth of human osteoclasts in a co-culture with normal osteoblasts. In SDM, in the presence of
recombinant RANKL, RAW 264.7 cells readily differentiated into tartrate resistant acid phosphatase (TRAP) positive multinucleated
osteoclast-like cells, a process that was enhanced with the addition of 1α,25-dihydroxyvitamin D3 (1,25D). While the osteoclasts grown in SDM were smaller in size compared with those derived in serum-replete media, their
resorptive capacity was significantly increased as indicated by a twofold increase in average resorption pit size. In conclusion,
we describe a defined model for studying osteoclast differentiation and activity in the absence of serum, which will be ideal
for studying the role of agonistic and antagonistic molecules in this process. 相似文献
992.
993.
Marcelo S. M. Faria José E. de Aguilar-Nascimento Osvânio S. Pimenta Luis C. AlvarengaJr Diana B. Dock-Nascimento Natasha Slhessarenko 《World journal of surgery》2009,33(6):1158-1164
Background Studies showing the improvement of insulin sensitivity by reducing the term of preoperative fasting are mostly done in patients
undergoing major operations. More information about the role of shortened preoperative fasting in perioperative metabolism
is needed for such elective minor/moderate abdominal procedures as laparoscopic cholecystectomy. We investigated the influence
of a carbohydrate-rich drink given 2 h before laparoscopic cholecystectomy on insulin resistance and the metabolic response
to trauma.
Methods A group of 21 female candidates (18–65 years old) for elective laparoscopic cholecystectomy were randomized to either an 8 h
fasting group (control group: n = 10) or to a group receiving 200 ml of a carbohydrate beverage containing 12.5% (25 g, 50 kcal per 100 ml and approximately
285 mOsm) of maltodextrine 2 h before operation (CHO group: n = 11). Blood samples for various biochemical assays were collected both at induction of anesthesia and after the 10th postoperative
hour. Insulin resistance was assessed by the HOMA-IR equation (Insulin (μU/ml) × blood glucose (mg/dl)/405).
Results There were no postoperative complications. Seventy percent (7/10) of the controls and 27.3% (3/11) of the CHO group experienced
at least one episode of vomiting (RR = 2.42, 95% Confidence Interval [CI] = 0.88–6.68; P = 0.08). Biochemical analysis showed that serum glucose (P < 0.01), insulin (P < 0.01), lactate/pyruvate ratio (P = 0.03), and triglycerides (P < 0.01) for the control group were higher than for the CHO group. The value of HOMA-IR was significantly greater (P = 0.03) in the conventionally fasted patients than in the CHO group.
Conclusions Abbreviation of the period of preoperative fasting and administration of a carbohydrate beverage diminishes insulin resistance
and the organic response to trauma. 相似文献
994.
Michelle da Silva Pradeep H. Navsaria Sorin Edu Andrew J. Nicol 《World journal of surgery》2009,33(2):215-219
Background Abdominal stab wounds with evisceration remain an indication for emergency laparotomy. The purpose of this study was validate
a policy of mandatory laparotomy for organ evisceration and a policy of selective nonoperative management with serial physical
abdominal examination for omentum evisceration.
Methods The charts of 379 patients with abdominal stab wounds who presented to our Level I trauma center over a 3-year (January 2005
to December 2007) period were retrospectively reviewed. Altogether, 66 (17.4%) patients with evisceration were identified
and included in the study. Indications for mandatory laparotomy were peritonitis, hemodynamic instability, organ evisceration,
and a high spinal cord or severe head injury with an abdominal stab wound. Further data gathered included the organ eviscerated,
intraabdominal organs injured, and complications. Injury severity was categorized using the revised trauma score (RTS), injury
severity score (ISS), and penetrating abdominal index (PATI).
Results Organ and omentum evisceration occurred in 35 (53%) and 31 (47%) patients, respectively. Organs eviscerated were as follows
(number of patients): small bowel in 27 (40.9%), stomach in 2 (3%), colon in 1 (1.5%), small bowel and stomach in 2 (3%),
and small bowel and colon in 3 (4.5%). The mean RTS, ISS, and PATI scores were 7.71, 13.74, and 8.26, respectively. Only two
(5.7%) patients with organ evisceration underwent a negative laparotomy. In total, 23 patients with omentum evisceration (21
with peritonitis, 1 with a head injury, 1 who failed abdominal observation) underwent therapeutic laparotomy. Six patients
with omentum evisceration were managed successfully nonoperatively. Two patients with left thoracoabdominal omentum evisceration
underwent delayed laparoscopy, which revealed a diaphragm injury in one patient. Overall, 57 (86.4%) patients with evisceration
had an intraabdominal injury that required repair.
Conclusions Evisceration should continue to prompt operative intervention. An exception can be made to a select few patients with omentum
evisceration with benign abdominal findings. 相似文献
995.
Fusion versus Bryan Cervical Disc in two-level cervical disc disease: a prospective,randomised study
In this prospective study, our aim was to compare the functional results and radiographic outcomes of fusion and Bryan Cervical
Disc replacement in the treatment of two-level cervical disc disease. A total of 65 patients with two-level cervical disc
disease were randomly assigned to two groups, those operated on with Bryan Cervical Disc replacement (31) and those operated
on with anterior cervical fusion with an iliac crest autograft and plate (34). Clinical evaluation was carried out using the
visual analogue scale (VAS), the Short Form 36 (SF-36) and the neck disability index (NDI) during a two year follow-up. Radiological
evaluation sought evidence of range of motion, stability and subsidence of the prosthesis. Substantial reduction in NDI scores
occurred in both groups, with greater percent improvement in the Bryan group (P = 0.023). The arm pain VAS score improvement was substantial in both groups. Bryan artificial cervical disc replacement seems
reliable and safe in the treatment of patients with two-level cervical disc disease. 相似文献
996.
Ryo Maeda Noritaka Isowa Hiroshi Miura Hirokazu Tokuyasu Yuji Kawasaki Kazumichi Yamamoto 《General thoracic and cardiovascular surgery》2009,57(12):667-670
This report presents a case of bilateral multiple sclerosing hemangiomas of the lung in a 73-year-old woman. A computed tomography
(CT) scan of the chest showed a total of three well-defined small nodules in the right and left lower lobes of the lung. Because
malignant metastatic lung tumors were highly suspected, a wedge resection of the left lower lobe was performed to obtain a
definitive diagnosis. Histopathologically, two tumors of the left lower lobe were composed of epithelial-like cuboidal cells
covering the surface of papillary protrusions and sheets of round to polygonal cells underneath the epithelial-like cells.
The final diagnosis was that both tumors were sclerosing hemangiomas. After surgery the residual lesion of the right lower
lobe was carefully followed by chest CT. The size of the right lung nodule did not change over the course of 9 years, and
no new lesion has emerged. 相似文献
997.
Gaurav Jain Atul Samaiya Namita Mohindra Kailash Patel 《The Indian journal of surgery》2009,71(1):35-37
Distant metastases are rare form of presentation of carcinoma gall bladder. Bony pain as initial presentation is quite unusual.
A 50-year-old woman presented with the pain in right shoulder. Investigation showed metastatic adenocarcinoma in the head
of humerus and the primary was found in the gall bladder. She received local radiotherapy for bone metastases and undergoing
systemic chemotherapy. Carcinoma gall bladder is a common abdominal malignancy, mostly presenting in advanced stage with abdominal
symptoms and obstructive jaundice. In presence of metastasis, the management is palliative and role of chemotherapy is limited
for palliation symptoms. 相似文献
998.
Christian-Dominik Peterlein Markus Dietmar Schofer Susanne Fuchs-Winkelmann Friedrich Georg Scherf 《Musculoskeletal surgery》2009,93(3):115-122
Despite excellent results, there is a lack of prospective studies analysing functional outcome and quality of life after computer-navigated
total knee arthroplasty. Fifty-two patients were investigated before and 6 months after surgery with the OrthoPilot navigation
system (Aesculap, Germany). We used the SF-36 Health Survey, the visual analog scale (VAS), the Lequesne score and the Knee
Society Score (KSS) for assessment. The operation was carried out by one single surgeon. At follow-up, the study population
achieved a significant pain reduction on the VAS from 71 to 21 points, an average decline of the Lequesne score from 16 to
7 points coming along with a significant ascent of the KSS from 84 to 157 points. Concerning the SF-36 Health Survey, most
of the patients re-achieved age- and gender-matched scores. Poor results were obtained in patients with multiple comorbidities
and a severe flexion contracture preoperative. 相似文献
999.
Wendy Mak Xinyu Shao Colin R. Dunstan Markus J. Seibel Hong Zhou 《Calcified tissue international》2009,85(6):538-545
Glucocorticoids exert both anabolic and catabolic effects on bone. Previously, we reported that endogenous glucocorticoids
control mesenchymal lineage commitment and osteoblastogenesis through regulation of Wnt signaling in osteoblasts. Here, we
investigated the effects of glucocorticoids on Wnt expression in mature osteoblasts. Mature osteoblasts and their immature
progenitors were separately isolated from Col2.3-GFP transgenic mice in which mature osteoblasts are identifiable through
GFP expression. mRNA levels of Wnt2, Wnt2b, Wnt4, Wnt5a, Wnt10b, and Wnt11 were 4- to 12-fold higher in osteoblasts compared
to their progenitors (P < 0.05). Expression of Wnt7b and Wnt10b in osteoblasts was modulated by corticosterone (CS), in a biphasic fashion with 3-
to 3.5-fold upregulation at 10 nM CS (P < 0.01) and 50% downregulation at 100 nM CS (P < 0.05). CS 100 nM also increased expression of the Wnt inhibitors sFRP-1 and DKK-1 two- to threefold (P < 0.05). We conclude that the contrasting anabolic and catabolic effects of glucocorticoids on bone are, at least in part,
mediated through the regulation of Wnt expression and its inhibitors in mature osteoblasts. 相似文献
1000.
Masafumi Imamura Yasutoshi Kimura Hideto Ito Takayuki Nobuoka Kazumitsu Koito Aya Sasaki Koichi Hirata 《Surgery today》2009,39(11):1006-1009
Acinar cell carcinomas (ACCs) of the pancreas are rare neoplasms, accounting for approximately 1% of all exocrine pancreatic
tumors. This type of tumor is known to be aggressive, although the survival rates are somewhat better than they are for ductal
carcinoma. The tumor tends to present nonspecific symptoms. It occurs in older patients, and jaundice is infrequent. This
report presents a case of ACC of the pancreas with intraductal papillary growth and lymph node metastasis. 相似文献