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101.
Aim: Bicycle riding is a common recreational and sport activity enjoyed by many children. Bicycle accidents are a common cause of abdominal injuries. We aim to establish the trend and the associated risk factor(s) of bicycle‐related abdominal injuries. Methods: A retrospective review of all children admitted following bicycle accidents to a single tertiary referral centre was carried out over an approximately 5‐year period. The data were tabulated and regression analyses were carried out. Results: Over the study period, 196 children were admitted into the Emergency Department. Abdominal injuries (16%) were the third largest group after orthopaedic and head injuries. There were 19 major visceral injuries, seven of whom underwent major surgeries. Forty‐two percent (8/19) of these major injuries were related to stunts. Over the same period, no child with head injury required any surgical intervention. In addition, there was a definite trend that abdominal injuries were accounting for greater percentage of bicycle‐related injuries in children. Conclusions: Severe intra‐abdominal trauma following bicycle injuries appears to be seen more often in adolescent males, especially when related to BMX stunts. These injuries have surpassed head injuries as the prime cause of morbidity from bicycle accidents. These injuries are largely preventable.  相似文献   
102.
103.
Surface reactivity of Calcium Phosphate materials--Hydroxyapatite (HA), Tricalcium Phosphate (beta-TCP), Hydroxyapatite-Tricalcium Phosphate (HA-TCP) were elucidated in a cell culture system. MG-63 osteoblast-like cells were seeded onto the ceramic discs to evaluate changes in the cell morphology and functionality with respect to the different substrates. The dissolution and re-precipitation of calcium phosphate phases on the surface of the discs in the culture medium was found to be prominent on beta-TCP when compared with HA. Low calcium (Ca), magnesium (Mg) and alkaline phosphatase (ALP) levels and high phosphorous (P) levels in the medium of beta-TCP were observed. This indicated that P must have leached out into the medium from beta-TCP and Ca in turn deposited from the medium onto beta-TCP resulting in the apatite phase transformation. The low ALP activity in beta-TCP medium is however an indication of low osteoblastic activity. Under the phase contrast microscope, the osteoblast cells around HA material were found to be confluent and viable, while in the vicinity of beta-TCP only cellular debris was observed. In the case of HA-TCP, only a few viable cells surrounded the material amidst the debris. Scanning electron microscopy revealed numerous cells on the surface of HA showing different cell behaviour like anchorage, attachment, adhesion and spreading in the early time period as the surface was only slightly disturbed with re-crystallisation. But with time the entire surface of HA had changed due to precipitation and re-crystallization which did not support cell behaviour while the cells surrounding the material showed normal growth. On the contrary, cells were scarcely observed on the entirely changed surface of beta-TCP and HA-TCP even from the earlier days of the culture and the morphology of cells surrounding the material too started changing. These results establish that HA promoted the activity of osteoblast cells. HA surface remained unaltered for some time, while the surface of beta-TCP underwent dissolution of surface ions and resulted in the re-crystallization of apatite over the surface. The resulting changes in the surrounding milieu of beta-TCP with high phosphate and low Ca levels probably was responsible for the death of the cells.  相似文献   
104.
Scaffolds which encourage the incorporation of a cell source for tissue engineering applications are critical determinants for clinical defects. Over the years, a number of biomaterials have emerged for cell support and growth, but only a few have demonstrated clinical efficacy. We therefore investigated an in-house-developed silica-based bioactive ceramic for its ability to support and sustain the growth of bone marrow-derived mesenchymal stem cells (BMSCs) in vitro. For this, MSCs aspirated from goat bone marrow were isolated and culture expanded on a novel triphasic ceramic composite coated hydroxyapatite (HASi) scaffold comprising hydroxyapatite, tricalcium phosphate and calcium silicate. The viability of cells that harbored on and within the material was ensured through fluorescence-activated cell sorting and confocal laser scanning microscope and for their anchorage sites by scanning electron microscopy. Interestingly, over the days in culture, cell-cell interactions gradually morphed into woven cell-sheets that spanned across the surface of the HASi, forming a canopy. To conclude, we have attempted to carry out the preliminary cytocompatibility studies of this novel ceramic to establish its appropriateness for bone tissue engineering application which is an important criterion in orthopaedic transplantation and regenerative surgery.  相似文献   
105.
Summary A monoclonal antibody has been produced againstXenopus laevis galactoside-binding neural-creststage lectin. This antibody inhibits lectin-mediated hemagglutination. Using this antibody in conjunction with immunohistochemical techniques, lectin deposition has been studied in embryos and tadpoles at different stages of morphogenesis, from initial neural crest migration, up to the formation of a swimming tadpole. Lectin levels change during development in different regions of the embryo and tadpole, decreasing in migratory cells, and increasing in sites where cells become more adhesive to one another. The results suggest that galactoside-binding lectins may be an important class of cellular adhesion molecules during these stages of development.  相似文献   
106.
There is little information concerning the prevalence and clinical correlates of increased pulmonary thallium-201 uptake during dipyridamole thallium-201 stress imaging. Accordingly, the clinical characteristics and quantitative thallium-201 findings were correlated with quantitative lung/heart thallium-201 ratio in 87 patients undergoing dipyridamole thallium-201 stress testing. Nineteen patients (22%) had an elevated ratio (greater than 0.51). These patients were more likely to have had an infarction, to be taking beta blockers, and have a lower rate-pressure product after dipyridamole administration than those with a normal ratio (p less than 0.03). An elevated ratio was associated with a greater likelihood of initial, redistribution and persistent defects, as well as left ventricular cavity dilatation on thallium-201 imaging (p less than 0.05). In addition, the number of myocardial segments demonstrating initial, redistribution and persistent defects was also greater in patients with increased ratios (p less than 0.03). Multivariate analysis demonstrated that the presence of redistribution and left ventricular cavity dilatation were the most significant correlates of lung/heart thallium-201 ratio. It is concluded that the prevalence of increased lung/heart thallium-201 ratio with dipyridamole thallium-201 stress imaging is similar to that seen with exercise stress imaging. As with exercise thallium-201 imaging, increased pulmonary thallium-201 uptake may be a marker of functionally more significant coronary artery disease.  相似文献   
107.
Objective – De‐novo psychiatric symptoms may develop within 3 months after a temporal lobectomy for epilepsy. The objective of this study was to identify presurgical risk factors for psychiatric symptoms. Methods – Twenty‐seven patients who had a temporal lobectomy for epilepsy were included. Twenty‐four had hippocampal sclerosis or gliosis, and three had cavernous haemagiomata. Twelve had operations on the left, and 15 on the right side. Twenty‐four patients were rendered free of seizures (SZ) with loss of awareness, three had early post‐operative convulsions, one continued to have habitual SZ. Results – Nine patients (33%) developed low mood, anxiety and emotional lability within 3 months after surgery. Patients with early post‐operative psychiatric symptoms were younger (27.9/34.8 years, P = 0.01), and more anxious on the presurgical Hospital Anxiety and Depression Scale (12/8.44, P = 0.02) than patients without post‐operative psychiatric symptoms. There was also an association between right temporal lobectomies and early post‐surgical symptoms (P = 0.02 Fisher’s exact test). Conclusion – Potential risk factors were age, anxiety and operation on the right side. Larger studies are required to determine if these risk factors are independent.  相似文献   
108.

Background

Genetic susceptibility to atypical hemolytic uremic syndrome (aHUS) may lie within genes regulating or activating the alternate complement and related pathways converging on endothelial cell activation.

Methods

We tested 32 Indian patients of aHUS negative for antibodies to complement factor H for genetic variations in a panel of 15 genes, i.e., CFH, CFHR1-5, CFI, CFB, C3, CD46, MASP2, DGKE, ADAMTS13, THBD and PLG using next-generation DNA sequencing and for copy number variation in CFHR1-3.

Results

Despite absence of a public database of exome variations in the Indian population and limited functional studies, we could establish a genetic diagnosis in 6 (18.8%) patients using a stringent scheme of prioritization. One patient carried a likely pathogenic variation. The number of patients carrying possibly pathogenic variation was as follows: 1 variation: 5 patients, 2 variations: 9 patients, 3 variations: 5 patients, 4 variations: 9 patients, 5 variations: 2 patients and 6 variations: 2 patients. Homozygous deletion of CFHR1-3 was present in five patients; none of these carried a diagnostic genetic variation. Patients with or without diagnostic variation did not differ significantly in terms of enrichment of genetic variations that were rare/novel or predicted deleterious, or for possible environmental triggers.

Conclusion

We conclude that genetic testing for multiple genes in patients with aHUS negative for anti-FH antibodies reveals multiple candidate variations that require prioritization. Population data on variation frequency of the Indian population and supportive functional studies are likely to improve diagnostic yield.
  相似文献   
109.

Objective

To evaluate the effect of integrity of dural sac in determining motor neurological recovery in patients with cauda equinal and epiconal injuries in vertebral fractures at thoracolumbar junction.

Methods

Thirty-one patients with single-level vertebra fracture over T12–L2 with cauda equinal or epiconal injuries that underwent posterior spinal decompression and stabilization were evaluated in the period between 2006 and 2012. All patients included had motor incomplete ASIA C in neurology and were either Type B or C (AO/Magerl classification) of fracture morphology. Radiologist opinion to confirm the level of conus in MRI was done preoperatively. Intraoperative findings with respect to intactness of dura was noted. All MRI images were postoperatively evaluated by an independent, blinded radiologist for evidence of dural breach caused by the trauma. All participants provided basic demographic data, ambulatory status, and current neurology and received neurologic examination at intervals. The differences in neurologic injury sites and functional walkers in patients with different levels of vertebral injury were analyzed. Receiver operating characteristic curve analysis was used to define the cut-off value of lower extremities motor score (LEMS) in functional walkers and non-walkers. All patients were seen at a postoperative follow-up of minimum 18 months.

Results

Data of the 31 patients were analyzed. Seventeen patients (55 %) had epiconus and lumbar roots lesions and 14 (45 %) had cauda equina lesions. The injury was at the T12 vertebra in 9 patients (29 %), L1 in 12 (39 %) and in L2 in 10 patients (32 %). Mean LEMS for patients with T12, L1, and L2 fractures were calculated. Fourteen patients had intraoperative findings of intact dura as against 17 patients with dural breach. MRI images when revisited by an independent radiologist by keeping him blind about the intraoperative surgeons findings showed statistically very good interobserver agreement (κ = 0.618) with regard to integrity of the dural sac. Postoperative neurological assessment at minimum 18 months follow-up showed that four out of the 14 patients with intact dura were walkers (28 %) whereas of the 17 patients with dural breach, 13 were walkers (82 %).

Conclusion

Neurological recovery in cauda equinal and epiconal injuries in thoracolumbar fractures is significantly less likely in an intact dural sac, probably because the dural breach prevents the roots to take as much impact as compared to an intact dural sac.
  相似文献   
110.
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