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1.

Background

Current blunt cerebrovascular injury (BCVI) grading grossly differentiates injury characteristics such as luminal stenosis (LS) and aneurysmal disease. The effect of increasing degree of LS beyond the current BCVI grading scale on stroke formation is unknown.

Study Design

BCVI over a 3-year period were retrospectively reviewed. To investigate influence of LS beyond the BCVI grading scale within aneurysmal and non-aneurysmal BCVI, grade 2 BCVI were subdivided into BCVI with ≥ 25% and ≤ 50% LS and BCVI with > 50% and ≤ 99% LS. Grade 3 BCVI were subdivided into BCVI with pseudoaneurysm (PSA) without LS and BCVI with PSA and LS. We hypothesized increased LS beyond the current BCVI grade distinctions would be associated with higher rates of stroke formation.

Results

312 BCVI were included, of which 140 were carotid BCVI and 172 vertebral BCVI. Sixteen carotid BCVI underwent endovascular intervention (EI) and 19 suffered a stroke. In carotid BCVI stroke rates increased sequentially with BCVI grade except in grade 3. There was a stroke rate of 12% in grade 1 carotid BCVI, 18% in grade 2, 6% in grade 3, and 31% in grade 4. In subgroup analysis for grade 2 carotid BCVI, BCVI with > 50% and ≤ 99% LS had higher rates of stroke (22% vs. 15%, p?=?0.44) than BCVI with ≥ 25% and ≤ 50% LS. In subgroup analysis of grade 3 carotid BCVI, BCVI with PSA and LS had higher rates of stroke (9% vs. 4%, p?=?0.48) than BCVI with PSA without LS. Higher rates of EI in grade 2 carotid BCVI with > 50% and ≤ 99% LS (22% vs. 5%, p?=?0.14) and grade 3 carotid BCVI with PSA and LS (35% vs. 4%, p?=?0.01) were noted in subgroup analysis.

Conclusion

Higher percentage LS beyond the currently used BCVI grading scale has a non-significantly increased rate of stroke in both aneurysmal and non-aneurysmal BCVI. Grade 3 BCVI with PSA and LS seems to be a high-risk subgroup. Use of EI confounds modern measurement of stroke risk in higher LS BCVI.  相似文献   
2.

Objectives

To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.

Design

Prospective intervention study.

Methods

Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.

Results

Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.

Conclusions

Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes.  相似文献   
3.
The following recommendations of the Neonatal Hemostasis Subcommittee of the Scientific and Standardization Committee of the ISTH for the management of neonatal immune thrombocytopenia were prepared by the working party on neonatal immune thrombocytopenia. Evaluation, diagnosis, and treatment of the mother and neonate with alloimmune and autoimmune thrombocytopenia are discussed and current recommendations provided. This document is likely to require frequent future revision(s).  相似文献   
4.
It has been previously demonstrated that the generation of measles virus (MV)-specific cytotoxicity (CTL) is reduced in patients with multiple sclerosis (MS). By contrast, CTL specific for influenza virus (FLU) and mumps virus is normal. It is uncertain if reduced CTL is limited to MV in MS patients, or if reduced CTL may be found to other viruses as well. Since MV-specific CTL is predominantly restricted by HLA class II molecules, while FLU-specific and mumps-specific CTL have large HLA class I-restricted components, reduced MV-specific CTL may reflect a broader reduction in HLA class II-restricted CTL in patients with MS. To examine this question we studied the generation of CTL specific for herpes simplex virus type I (HSV). HSV-specific CTL, like MV-specific CTL is predominantly restricted by HLA class II molecules. We found that patients with MS had reduced generation of CTL to both MV and HSV. Most, but not all patients who had reduced generation of CTL to one virus also had a similar impairment with respect to the second virus. Some patients, however, had a reduction in the generation of CTL only to MV or to HSV. These findings extend our earlier observations regarding reduced MV-specific CTL in patients with MS to a second HLA class II-restricted virus, HSV. Such a reduction may reflect discrete impairments in immune function to separate viruses, possibly those that are associated with viral persistence, or may reflect a more generalized defect in HLA class II-restricted CTL.  相似文献   
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We report a case of neonatal alloimmune thrombocytopenia and intracranial hemorrhage in an infant whose mother received immunizations of paternal mononuclear cells. This therapy is designed to prevent unexplained first trimester miscarriages. No previous cases of platelet autoimmunization associated with maternal immunization with paternal mononuclear cells has been reported. Treatment with antenatal maternal infusions of intravenous gamma globulin (IVGG) did not prevent fetal thrombocytopenia, but IVGG may become the treatment of choice for postnatal, antibody-mediated thrombocytopenia of the newborn.  相似文献   
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