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Introduction: Ischemic stroke is becoming a primary cause of disability and death worldwide. To date, therapeutic options remain limited focusing on mechanical thrombolysis or administration of thrombolytic agents. However, these therapies do not promote neuroprotection and neuro-restoration of the ischemic area of the brain.

Areas covered: This review highlights the option of minimal invasive, intra-arterial, administration of biological agents for stroke therapy. The authors provide an update of all available studies, discuss issues that influence outcomes and describe future perspectives which aim to improve clinical outcomes. New therapeutic options based on cellular and molecular interactions following an ischemic brain event, will be highlighted.

Expert opinion: Intra-arterial administration of biological agents during trans-catheter thrombolysis or thrombectomy could limit neuronal cell death and facilitate regeneration or neurogenesis following ischemic brain injury. Despite the initial progress, further meticulous studies are needed in order to establish the clinical use of stem cell-induced neuroprotection and neuroregeneration.  相似文献   

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Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury.  相似文献   
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OBJECTIVES: Persisting air leakage after pulmonary resection remains a significant problem. The aim of the study was to evaluate the incidence of air leakage after standard lobectomy and test the efficacy and safety of TachoComb (TC). METHODS: A total of 189 patients undergoing lobectomy were enrolled in a multi-centre, open, randomised, and prospective study to test the efficacy and safety of TachoComb (TC) for air leakage treatment. Air leakage was assessed by water submersion test, and scored as grades 0 if no, 1 if countable, 2 if a stream of and 3 if coalescent bubbles have been observed. Any sites with grade 3 air leakage received further stapling or limited suturing until grade 0, 1 or 2 was obtained. Treatment of air leakage was done with TC or suturing according to randomisation. Air leakage was assessed by further submersion tests. Postoperative air leakage was assessed using the Pleur-Evac system. RESULTS: Overall incidence of air leakage 48+/-6 h after surgery was 34% for TC and 37% for standard treatment (P=0.76). The reduction of intra-operative air leak intensity in the subgroup with grades 1-2 was significantly higher for the TC group (P=0.015). Postoperative air leakage intensity in the subgroup with air leakage grades 1-2 was lower for TC than standard treatment (P=0.047). The mean duration of postoperative air leakage in the subgroup with grades 1-2 was shorter for the TC group than for standard treatment, i.e. 1.9+/-1.4 vs. 2.7+/-2.2 days (P=0.015). CONCLUSIONS: TC could be proven as well-tolerated and safe. In the subgroup of patients with established air leakage, TC showed superior potential in reduction of intra-operative air leakage as well as in reduction of intensity and duration of postoperative air leakage.  相似文献   
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BACKGROUND: Early, rapid bone loss and fractures after cardiac transplantation are well-documented complications of steroid administration; therefore, we undertook this study on the effects of long-term calcitonin on steroid-induced osteoporosis. METHODS: Twenty-three heart transplant recipients on maintenance immunosuppression with cyclosporine, mycophenolate mofetil and prednisone were retrospectively studied. All patients received long-term prophylactic treatment with elemental calcium and vitamin D. Twelve (52.2%) patients also received long-term intranasal salmon calcitonin, whereas 11 (47.8%) received none. Bone mineral density and vertebral fractures were assessed at yearly intervals. Statistical comparisons between each group's bone loss during the first year and in the early (1 to 3 years), intermediate (4 to 6 years) and late (7+ years) post-transplantation periods were done. RESULTS: Lumbar spine bone loss was significant during the early follow-up period in the group not receiving calcitonin (0.744 +/- 0.114 g/cm(2) vs 0.978 +/- 0.094 g/cm(2) [p = 0.002]). The calcitonin group showed bone mineral density (BMD) levels within normal average values throughout the study period. BMD increased in the no-calcitonin group during the intermediate (4 to 6 years) and late (7+ years) follow-up periods, with values approaching normal average and no significant difference between the 2 groups (0.988 +/- 0.184 g/cm(2) vs 0.982 +/- 0.088 g/cm(2) [p = 0.944] and 0.89 +/- 0.09 g/cm(2) vs 1.048 +/- 0.239 g/cm(2) [p = 0.474], respectively). CONCLUSIONS: Prophylactic treatment with intranasal salmon calcitonin prevents rapid bone loss associated with high-dose steroids early after cardiac transplantation. Long-term administration does not seem warranted in re-establishing BMD.  相似文献   
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Apoptosis is critical for organ development, tissue homeostasis, the elimination of abnormal cells and the maintenance of immune homeostasis by variable regulatory mechanisms. The death of T lymphocytes following their activation involves a series of proteases (caspases), which comprise the central executioners of apoptosis. Abnormal regulation of apoptosis results in disease. T-cell resistance against apoptosis contributes to inappropriate T-cell accumulation and the perpetuation of the chronic inflammatory process in inflammatory bowel disease with potential tumourigenic effect. The use of antitumour necrosis factor-alpha, anti-interleukin-6R and anti-interleukin-12 antibodies suppresses colitis activity by induction of T-cell apoptosis, thereby having important implications for the design of effective therapeutic strategies in inflammatory bowel diseases. Contrary to international data, the incidence of cancer in Greek patients with inflammatory bowel disease appears to be low. A balance between cell proliferation (Ki-67 overexpression) and apoptosis (Bax protein overexpression) may partly explain the low incidence of cancer development in Greek inflammatory bowel disease patients.  相似文献   
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BACKGROUND: The phenomenon of the spontaneous disappearance of herniated discs is well known. CASE REPORT: The case of a 74-year-old male presenting with a large disc herniation at L5-S1, experiencing moderate sciatic pain, and having the straight-leg-raising test positive at 30 degrees is presented. The disc herniation was documented by computed tomography. He was treated conservatively with medication and physical therapy. One year later the patient was clinically reevaluated. He proved to be symptom-free and the follow-up computed tomography revealed spontaneous disappearance of the herniated disc fragment. The disc regression could have been due to dehydration, resorption as a result of an inflammatory reaction, or retraction into the intervertebral space. CONCLUSIONS: This report discusses the three aforementioned possible explanations and underlines the need for limiting surgical treatment strictly to patients with neurological deficits, severe unremitting leg pain despite conservative measures, and repeated time loss from work.  相似文献   
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