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Post-traumatic ulnar carpal translocation is a rare, severe ligamentous injury to the wrist. Radiologic findings include widening of the radiocarpal joint space at the radial styloid process and ulnar displacement of the carpus. Less than 50% of the lunate articulates with the radius in the neutral position; the lunate is tilted dorsally with palmar subluxation due to a ruptured radioscapholunate (RSL) ligament. This malposition should be called rotatory palmar subluxation of the lunate (RPSL), by analogy to rotatory subluxation of the scaphoid (RSS). In contrast to dorsiflexed intercalated segment instability (DISI), in RPSL the RSL ligament is ruptured and, in the majority of cases, the scapholunate ligament remains intact. A prompt diagnosis should lead to successful treatment.  相似文献   
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Epileptic seizures occur because of the increased excitability of neuronal cells in the brain that is of a mainly genetic origin in at least one third of all epilepsies. The so far identified mutations in inherited monogenic idiopathic epilepsies mainly affect ion channel genes and could be linked to both focal and generalized forms of inherited epilepsy. In a healthy brain, ion channels in the membranes of excitatory and inhibitory neurons are responsible for a neuronal balance. Disruption of this balance by changing the ion channel function can therefore lead to epileptic seizures. In this overview, we describe and discuss known epilepsy-associated mutations in ion channel genes, their functional consequences, and the resulting disease mechanisms.  相似文献   
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Osteoporosis is characterized by enhanced differentiation of bone‐resorbing osteoclasts, resulting in a rapid loss of functional trabecular bone. Bone‐forming osteoblasts and osteoblast‐derived osteocytes perform a key role in the regulation of osteoclast development by providing both the pro‐osteoclastogenic cytokine receptor activator of NF‐κB ligand (RANKL) and its natural decoy receptor osteoprotegerin (OPG). By regulating the RANKL/OPG ratio, osteoblasts hence determine the rate of both osteoclast differentiation and bone turnover. Here, we describe a novel role for liver X receptors (LXRs) during the crosstalk of bone‐forming osteoblasts and bone‐resorbing osteoclasts. By using a system of osteoblast/osteoclast cocultures, we identify LXRs as regulator of RANKL expression and the RANKL/OPG ratio in osteoblasts. Activation of LXRs drastically reduced the RANKL/OPG ratio and interfered with osteoblast‐mediated osteoclast differentiation in vitro. During an ovariectomy (OVX)‐induced model of postmenopausal osteoporosis, the application of an LXR agonist shifted the RANKL/OPG ratio in vivo, ameliorated the enhanced osteoclast differentiation, and provided complete protection from OVX‐induced bone loss. These results reveal an unexpected involvement of LXRs in the regulation of bone turnover and highlight a potential role for LXRs as novel targets in the treatment of osteoporosis and related diseases. © 2012 American Society for Bone and Mineral Research.  相似文献   
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Vector-borne infections of humans with the protozoan parasite Leishmania (L.) infantum can cause a systemic and potentially lethal disease termed visceral leishmaniasis. In the corresponding mouse model, an intravenous infection with L. infantum leads to the persistence of parasites in various organs, including bone marrow (BM). Considering the anatomical proximity between the BM and the cortical bone, we investigated whether a chronic infection with L. infantum affected bone homeostasis. Unexpectedly, chronic infection with L. infantum caused an increase in bone mass in mice. In vivo, an increased number of osteoblasts and osteocytes and a decreased maturation of osteoclasts characterized the phenotype. Confocal laser scanning fluorescence microscopy confirmed the infection of BM macrophages but also revealed the presence of parasites in osteoclasts. In vitro, mature osteoclasts took up L. infantum parasites. However, infection of osteoclast progenitors abolished their differentiation and function. In addition, secretory products of infected BM–derived macrophages inhibited the maturation of osteoclasts. Both in vitro and in vivo, infected macrophages and osteoclasts showed an enhanced expression of the anti-osteoclastogenic chemokine CCL5 (RANTES). Neutralization of CCL5 prevented the inhibition of osteoclast generation seen in the presence of culture supernatants from L. infantum-infected macrophages. Altogether, our study shows that chronic infection with Leishmania increases bone mass by inducing bone formation and impairing osteoclast differentiation and function. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
47.
This study investigates the effects of kyphoplasty on pain and mobility in patients with osteoporosis and painful vertebral fractures compared with conventional medical management. INTRODUCTION: Pharmacological treatment of patients with primary osteoporosis does not prevent pain and impaired activity of patients with painful vertebral fractures. Therefore, we evaluated the clinical outcome after kyphoplasty in patients with vertebral fractures and associated chronic pain for >12 months. MATERIALS AND METHODS: Sixty patients with primary osteoporosis and painful vertebral fractures presenting for >12 months were included in this prospective, nonrandomized controlled study. Twenty-four hours before performing kyphoplasty, the patients self-determined their inclusion into the kyphoplasty or control group so that 40 patients were treated with kyphoplasty, whereas 20 served as controls. This study assessed changes in radiomorphology, pain visual analog scale (VAS) score, daily activities (European Vertebral Osteoporosis Study [EVOS] score), number of new vertebral fractures, and health care use. Outcomes were assessed before treatment and at 3 and 6 months of follow-up. All patients received standard medical treatment (1g calcium, 1000 IE vitamin D(3), standard dose of oral aminobisphosphonate, pain medication, physical therapy). RESULTS: Kyphoplasty increased midline vertebral height of the treated vertebral bodies by 12.1%, whereas in the control group, vertebral height decreased by 8.2% (p = 0.001). Augmentation and internal stabilization by kyphoplasty resulted in a reduction of back pain. VAS pain scores improved in the kyphoplasty group from 26.2 +/- 2 to 44.2 +/- 3.3 (SD; p = 0.007) and in the control group from 33.6 +/- 4.1 to 35.6 +/- 4.1 (not significant), whereas the EVOS score increased in the kyphoplasty group from 43.8 +/- 2.4 to 54.5 +/- 2.7 (p = 0.031) and in the control group from 39.8 +/- 4.5 to 43.8 +/- 4.6 (not significant). The number of back pain-related doctor visits within the 6-month follow-up period decreased significantly after kyphoplasty compared with controls: mean of 3.3 visits/patient in the kyphoplasty group and a mean of 8.6 visits/patient in the control group (p = 0.0147). CONCLUSIONS: The results of this study show significantly increased vertebral height, reduced pain, and improved mobility in patients after kyphoplasty. Kyphoplasty performed in appropriately selected osteoporotic patients with painful vertebral fractures is a promising addition to current medical treatment.  相似文献   
48.

Background

Febrile urinary tract infections (fUTIs) are common after kidney transplantation (KTx); however, prospective data in a multicenter pediatric cohort are lacking. We designed a prospective registry to record data on fUTI before and after pediatric KTx.

Methods

Ninety-eight children (58 boys and 40 girls)?≤?18 years from 14 mid-European centers received a kidney transplant and completed a 2-year follow-up.

Results

Posttransplant, 38.7 % of patients had at least one fUTI compared with 21.4 % before KTx (p?=?0.002). Before KTx, fUTI was more frequent in patients with congenital anomalies of kidneys and urinary tract (CAKUT) vs. patients without (38 % vs. 12 %; p?=?0.005). After KTx, fUTI were equally frequent in both groups (48.7 % vs. 32.2 %; p?=?0.14). First fUTI posttransplant occurred earlier in boys compared with girls: median range 4 vs. 13.5 years (p?=?0.002). Graft function worsened (p?<?0.001) during fUTI, but no difference was recorded after 2 years. At least one recurrence of fUTI was encountered in 58 %.

Conclusion

This prospective study confirms a high incidence of fUTI after pediatric KTx, which is not restricted to patients with CAKUT; fUTIs have a negative impact on graft function during the infectious episode but not on 2-year graft outcome.
  相似文献   
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Background Retrospective evaluation of the prognosis scores of Tokuhashi and Tomita for life expectancy in 37 consecutive patients with spinal metastases secondary to renal cancer who underwent surgery. The score of Tokuhashi, composed of six parameters, each rated from zero to two, has been proposed in 1990 for the prognostic assessment of patients with spinal metastases. In 2001, Tomita et al. created another prognostic score, composed of three parameters, growth behaviour of the primary tumor (slow, moderate and rapid) and the evidence of visceral and bony metastases. Methods Thirty-seven patients, surgically treated for vertebral metastases secondary to renal cancer were studied. The scores according to Tokuhashi and Tomita were calculated for each patient. Results Applying the Tokuhashi Score for the estimation of life expectancy of renal cancer patients with vertebral metastases was found to provide very reliable results with a statistically high significance. The analysis according to Tomita showed no correlation between predicted and real survival. The statistical analysis did not show any significance. Conclusion For surgical decisions in renal cancer patients with spinal metastases, the prognostic score of Tokuhashi appears to be much more valuable than the Tomita score.  相似文献   
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