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151.
OBJECTIVE: Characterize maturation of transcallosal inhibition (ipsilateral silent period [iSP]) in attention deficit/hyperactivity disorder (ADHD) using transcranial magnetic stimulation (TMS). BACKGROUND: Maturation of the iSP is related to acquisition of fine motor skills in typically developing children suggesting that dexterous fine motor skills depend upon mature interhemispheric interactions. Since neuromotor maturation is abnormal in boys with ADHD we hypothesized that iSP maturation in these children would be abnormal. We studied iSP maturation in 12 boys with ADHD and 12 age-matched, typically developing boys, 7-13 years of age. METHODS: Surface electromyographic activity was recorded from right first dorsal interosseus (FDI). During background activation, focal TMS was delivered at maximal stimulator output over the ipsilateral motor cortex. RESULTS: Maturation of finger speed in boys with ADHD was significantly slower than that in the control group. The iSP latency decreased with age in the control group but not in the ADHD group. CONCLUSIONS: These findings suggest the presence of a complex relationship between abnormalities of certain interhemispheric interactions (as represented by iSP latency) and delayed maturation of neuromotor skills in boys with ADHD. SIGNIFICANCE: These data provide preliminary physiologic evidence supporting delayed or abnormal development of interhemispheric interactions in boys with ADHD.  相似文献   
152.
Smith KD  Kallhoff V  Zheng H  Pautler RG 《NeuroImage》2007,35(4):1401-1408
Axonopathy is a pronounced attribute of many neurodegenerative diseases. In Alzheimer's disease (AD), axonal swellings and degeneration are prevalent and may contribute to the symptoms of AD senile dementia. Current limitations in identifying the contribution of axonal damage to AD include the inability to detect when this damage occurs in relation to other identifiers of AD because of the invasiveness of existing methods. To overcome this, we further developed the MRI methodology Manganese Enhanced MRI (MEMRI) to assess in vivo axonal transport rates. Prior to amyloid-beta (Abeta) deposition, the axonal transport rates in the Tg2576 mouse model of AD were normal. As Abeta levels increased and before plaque formation, we observed a significant decrease in axonal transport rates of the Tg2576 mice compared to controls. After plaque formation, the decline in the transport rate in the Tg2576 mice became even more pronounced. These data indicate that in vivo axonal transport rates decrease prior to plaque formation in the Tg2576 mouse model of AD.  相似文献   
153.
Purpose

At present, uniformity does not exist with regard to the indication criteria of seminal vesicle (SV) biopsies. The aim of this study was to define the ultrasonographic (US) patterns observed in SV invaded by prostate cancer (PCa), and propose an extended prostate biopsy protocol when SV invasion (SVI) is suspected.

Methods

We reviewed 1.252 patients who underwent an initial transrectal ultrasound-guided prostate biopsy for suspicious PCa. We performed a 14-core biopsy scheme, as first intention, including 1 SV sample on each side when SVI is suspected: a nodule at the base of prostate (determined by digital rectal examination or US) and/or an US pattern that suggests a SVI. US patterns of SVs were classified as abnormal by a variation of the body anterior-posterior diameter, asymmetry of the volume, parietal thickness, distance between the SVs and the rectal surface, and altered echogenicity of SVs and the base of the prostate.

Results

Of the 137 biopsies performed in SVs, the SVI by PCa was diagnosed in 66.5% of candidate patients. The overall prevalence of SVI was 28.5%. No significant difference was noted between the patients with SVI and without SVI, when comparing age, prostate volume, and total core length, except for preoperative PSA serum levels. The sensitivity of any abnormal finding on transrectal ultrasound for the presence of SVI by PCa is 90.8%, whereas the specificity is 96%.

Conclusions

We believe that an extended prostate biopsy protocol to provide the possibility of taking one biopsy core of each SV when SVI is suspected should be considered a complementary procedure for PCa staging.

  相似文献   
154.
BACKGROUND:Fraction of exhaled nitrous oxide (FeNO) is a known marker of airway inflammation and a topic of recent investigation for asthma control in children.OBJECTIVE:To investigate the relationship among FeNO and bronchodilator response measured by spirometry and types of inhaled corticosteroids (ICS).METHODS:A one-year review of children tested with spirometry and FeNO in a regional pediatric asthma centre was conducted.RESULTS:A total of 183 children were included (mean [± SD] age 12.8±2.8 years). Fluticasone was used most commonly (n=66 [36.1%]), followed by ciclesonide (n=50 [27.3%]). Most children (n=73 [39.9%]) had moderate persistent asthma. Increased FeNO was associated with percent change in forced expiratory volume in 1 s (FEV1) after bronchodilator adjusted for allergic rhinitis, parental smoking and ICS type (B=0.08 [95% CI 0.04 to 0.12]; P<0.001). Similarly, FeNO was associated with percent change in forced expiratory flow at 25% to 75% of the pulmonary volume (FEF25–75) after bronchodilator adjusted for parental smoking and ICS type (B=0.13 [95% CI 0.01 to 0.24]; P=0.03). FeNO accounted for only 16% and 9% of the variability in FEV1 and FEF25–75, respectively. Mean-adjusted FeNO was lowest in fluticasone users compared with no ICS (mean difference 18.6 parts per billion [ppb] [95% CI 1.0 to 36.2]) and there was no difference in adjusted FeNO level between ciclesonide and no ICS (5.9 ppb [95% CI −9.0 to 20.8]).CONCLUSION:FeNO levels correlated with bronchodilator response in a regional pediatric asthma centre. However, FeNO accounted for only 16% and 9% of the variability in FEV1 and FEF25–75, respectively. Mean adjusted FeNO varied according to ICS type, suggesting a difference in relative efficacy between ICS beyond their dose equivalents.  相似文献   
155.
AIM: To evaluate the safety and efficacy of the permanent high interventricular septal pacing in a long term follow up, as alternative to right ventricular apical pacing.METHODS: We retrospectively evaluated: (1) 244 patients (74 ± 8 years; 169 men, 75 women) implanted with a single (132 pts) or dual chamber (112 pts) pacemaker (PM) with ventricular screw-in lead placed at the right ventricular high septal parahisian site (SEPTAL pacing); (2) 22 patients with permanent pacemaker and low percentage of pacing (< 20%) (NO pacing); (3) 33 patients with high percentage (> 80%) right ventricular apical pacing (RVA). All patients had a narrow spontaneous QRS (101 ± 14 ms). We evaluated New York Heart Association (NYHA) class, quality of life (QoL), 6 min walking test (6MWT) and left ventricular function (end-diastolic volume, LV-EDV; end-systolic volume, LV-ESV; ejection fraction, LV-EF) with 2D-echocardiography.RESULTS: Pacing parameters were stable during follow up (21 mo/patient). In SEPTAL pacing group we observed an improvement in NYHA class, QoL score and 6MWT. While LV-EDV didn’t significantly increase (104 ± 40 mL vs 100 ± 37 mL; P = 0.35), LV-ESV slightly increased (55 ± 31 mL vs 49 ± 27 mL; P = 0.05) and LV-EF slightly decreased (49% ± 11% vs 53% ± 11%; P = 0.001) but never falling < 45%. In the RVA pacing control group we observed a worsening of NYHA class and an important reduction of LV-EF (from 56% ± 6% to 43% ± 9%, P < 0.0001).CONCLUSION: Right ventricular permanent high septal pacing is safe and effective in a long term follow up evaluation; it could be a good alternative to the conventional RVA pacing in order to avoid its deleterious effects.  相似文献   
156.

Background

Despite a general agreement about effectiveness of video-assisted thoracic surgery (VATS) lobectomy the surgical technique is still not standardized, and many technical variations have been described until now. We describe our technique to perform thoracoscopic lobectomy by a caudal approach.

Methods

We studied a position in which the operator stays from the inferior side of the thorax, positioning the patients in a lateral sitting position. This position ensures the operator to enjoy all the benefits of the anterior and posterior approach limiting the disadvantages of both. The surgeon maneuvers are further assisted and simplified by the movement of the surgical bed.

Results

We perform 23 “caudal video assisted-lobectomy” for non-small cell lung cancer. The conversion rate was 0% and we had no complications related with the new approach.

Conclusions

We think that our new position could be considered a further effective technical variation to perform VATS-lobectomy.  相似文献   
157.

Background

Monoclonal gammopathies encompass a wide range of diseases characterized by the monoclonal expansion of a B-cell clone. Despite emerging therapeutic strategies, chances of survival of patients who are affected are still scarce, which implies that new tools are necessary not only for the diagnosis but also for the follow-up of patients affected by such diseases. In this context, the use of free light chains (FLCs) has been incorporated into many guidelines.Likewise, tumor microenvironment is consistently gaining importance as role player in tumor pathogenesis. Specifically, Syndecan-1 (CD138), a heparan-sulfate proteoglycan is attracting interests as it is highly expressed and shed by myeloma plasma-cells.The aim of our study was to analyze CD138 levels in the serum of patients affected by multiple myeloma or light chain only disease, and to compare the values obtained with free light chain (FLC) kappa, lambda and FLC ratio in both groups of patients.

Methods

84 patients affected by Multiple Myeloma and Light Chain Myeloma were recruited for this study. Serum CD138 was assessed by ELISA (Diaclone Research, France) and FLC values were quantified by nephelometry (Freelite TM Human Kappa and Lambda Free Kits, The Binding Site, UK). Data was analyzed by GraphPad Prism software and Statgraph.

Results

We observed higher CD138 mean values in myeloma patients compared to the light chain only myeloma group. A positive linear regression of CD138 and FLC was observed in the light chain only cohort as opposed to myeloma patients which show an inverse trend.

Conclusions

The study highlighted an existing relationship between FLCs and CD138 and wishes to seek also a correlation in order to rapidly and efficiently perform diagnosis and different diagnostic schemes.  相似文献   
158.
159.
Nutritional and hygienic practices contribute to high morbidity and mortality rates related to malnutrition in Madagascar. This study, a research effort that brought together charitable organisations, non-governmental organisations (NGOs) and university collaborators, investigates women's health knowledge in the Anosy region of Madagascar. The needs assessment sought to characterise women's knowledge and understanding of nutrition and hygiene. Eight focus groups of 13-60 women each were conducted in the seven most impoverished communes of the Anosy region (n=373). Participants were recruited with the aid of a UK-Malagasy partnered NGO, Azafady. Study findings show that women fully understand the interplay between poor nutrition, hygiene and malnutrition but are unable to change everyday practices because the barriers to better nutrition and hygiene seem beyond their control. These findings may be used to prioritise projects and research seeking to improve nutrition and hygiene, thus reducing malnutrition in the Anosy region.  相似文献   
160.
Role of the B domain for factor VIII and factor V expression and function   总被引:4,自引:3,他引:4  
Pittman  DD; Marquette  KA; Kaufman  RJ 《Blood》1994,84(12):4214-4225
Factor V and factor VIII are homologous cofactors in the blood coagulation cascade that have the domain structure A1-A2-B-A3-C1-C2, of which the B domain has extensively diverged. In transfected COS-1 monkey cells, expression of factor VIII is approximately 10-fold less efficient than that of factor V, primarily because of inefficient protein secretion and, to a lesser extent, reduced mRNA expression. To study the functional significance and effect of the B domain on expression and activity, chimeric cDNAs were constructed in which the B domains of factor V and factor VIII were exchanged. Expression of a factor VIII chimera harboring the B-domain of factor V yielded a fully functional factor VIII molecule that was expressed twofold more efficiently than wild-type factor VIII because of increased mRNA expression. Thus, sequences within the factor VIII B domain were not responsible for the inefficient secretion of factor VIII compared with factor V. Expression of a factor V chimera harboring the B domain of factor VIII was slightly reduced compared with wild-type factor V, although the secreted molecule had significantly reduced procoagulant activity correlating with dissociated heavy and light chains and resistance to thrombin activation. Interestingly, the factor V chimera containing the factor VIII B domain was efficiently activated by Russell's viper venum (RVV). A factor V B domain deletion (residues 710- 1545) molecule also exhibited significantly reduced procoagulant activity caused by resistance to thrombin cleavage and activation, although this molecule was activatable by RVV. These results show that, in contrast to factor VIII, thrombin activation of factor V requires sequences within the B domain. In addition, thrombin activation of factor V occurs through a different mechanism than activation by RVV.  相似文献   
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