Vascular thoracic outlet syndrome

Abstract The surgical treatment of 30 cases of vascular thoracic outlet syndrome (TOS) in 25 patients is presented. Patients included 17 women and 8 men with average age of 26.1 years. The causes of compression were cervical rib (n = 16), soft tissue anomalies (n = 12), and scar tissue after clavicle fracture (n = 2). Ten subclavian artery aneurysms containing intraluminal thrombus as well as one subclavian artery occlusion were found. All such cases had multiple distal arterial embolization. Presenting features of cases with arterial TOS included: hand ischemia (n = 11), transient ischemic attack (TIA) (n = 1), and claudication or vasomotor phenomena during the arm hyperabduction (n = 11). Two patients with venous TOS developed hand edema during arm hyperabduction, and five other patients had axillary-subclavian venous thrombosis. In all cases decompressive procedures using a combined supraclavicular and infraclavicular approach were performed. Decompression was achieved by cervical rib excision (n = 12), combined cervical and first rib excision (n = 4), and first rib excision (n = 14). In all cases division of all soft tissue elements was also accomplished. Associated vascular procedures included resection and replacement of 10 subclavian artery aneurysms, one subclavian-axillary and one axillary-brachial bypass, as well as nine brachial embolectomies. All five cases with axillary-subclavian vein thrombosis before decompression were treated with anticoagulant therapy. The mean follow-up period was 3 years and 2 months (range 1 to 6 years). Two pleural entry injuries and two transient brachial plexus injuries were noted. All reconstructed arteries were patent during the follow-up period. Complete resolution of symptoms with a return to full activity was noticed in all cases with arterial TOS and in two cases with venous TOS without axillary-subclavian vein thrombosis. In cases with axillary-subclavian vein thrombosis relief of symptoms was mild, and there were limitations on daily activity. Vascular TOS is seen less frequently than the neurogenic form; however, in most cases it requires surgical treatment. We prefer a combined supraclavicular and infraclavicular approach because it offers complete exposure of the subclavian artery, cervical and first ribs, and all soft tissue anomalies. Electronic Publication     

Daily life blood pressure changes are steeper in hypertensive than in normotensive subjects

Target organ damage in hypertensive patients is related to their increased average blood pressure and greater 24-hour blood pressure variability. Whether the rate of blood pressure changes is also greater in hypertension, producing a greater stress on arterial walls, is not known, however. Our study aimed at addressing this issue by computer analysis of 24-hour ambulatory intra-arterial blood pressure recordings in 34 subjects (29 males), 13 normotensive subjects and 21 uncomplicated hypertensive subjects (mean age+/-SD, 40.4+/-11.8 years). The number, slope (mm Hg/s), and length (beats) of systolic blood pressure ramps of 3 or more consecutive beats characterized by a progressive increase (+) or reduction (-) in systolic blood pressure of at least 1 mm Hg per beat were computed for each hour and for the whole 24-hour period. Twenty-four-hour average systolic blood pressure was 112.9+/-2.1 and 159.4+/-5.7 mm Hg in normotensive and hypertensive subjects, respectively. Over the 24 hours, the number and length of systolic blood pressure ramps were similar in both groups, whereas the slope was markedly different (24-hour mean+/-SE slope, 4.80+/-0.30 in normotensives and 6.50+/-0.40 mm Hg/s in hypertensives, P<0.05). Ramp slope was not influenced by age or reflex pulse interval changes, but it was greater for higher ramp initial systolic blood pressure values. Thus, in daily life, hypertensive subjects are characterized by steeper blood pressure changes than normotensives, and this, regardless of the mechanisms, may have clinical implications, because it may be associated with greater traumatic effect on the vessel walls of hypertensive patients.     

Overview of current approaches for treating word retrieval deficits demonstrates need for focused research questions and appraisal of the methodological quality of evidence

This review provides a summary and appraisal commentary on the treatment review by Schweng Casarin, F., Branco, L., Pereira, N., Kochhann, R., Gindri, G., & Paz Fonseca, R. (2014). Rehabilitation of lexical and semantic communicative impairments: An overview of available approaches. Dementia & Neuropsychologia, 8, 266–277. Sources of funding and disclosures of interest: Several of the authors received a CAPES scholarship for Master’s, PhD, or postdoctoral studies. The authors report no conflicts of interests.     

Behavioural and neural changes after a “choice” therapy for naming deficits in aphasia: preliminary findings

Background: Anomia, difficulty producing words, is a pervasive symptom of many individuals with aphasia. We have developed a treatment for naming deficits—the Phonological Components Analysis (PCA) protocol—that has proven efficacious in improving word-finding abilities for individuals with post-stroke aphasia.

Aims: The aim of this investigation is to present preliminary findings exploring the potential influence of choice—that is the active engagement of a participant in therapy—on our PCA treatment.

Methods & Procedures: Five individuals with aphasia were treated in one of two conditions—Choice or No Choice. Potential changes in neural activation as a function of the treatment were also investigated. Two individuals (one from each condition) underwent functional MRI (fMRI) pre- and post-therapy.

Outcomes & Results: All the individuals demonstrated a significant treatment effect immediately post-treatment and at a 4-week follow-up and four of the five participants at an 8-week follow-up. Three also demonstrated generalisation to untrained items. Unfortunately, no clear-cut patterns emerged to allow us to make claims about the influence of choice, per se, on the behavioural manifestations of improved naming. Interestingly, the participant from the Choice condition showed neural activation changes post-treatment in frontal and parietal regions that were not evident for the participant in the No Choice condition. Moreover, these changes were accompanied by a larger treatment effect for that individual and generalisation to a novel naming task.

Conclusion: The efficacy of PCA treatment for naming deficits is further supported. In addition, the neuroimaging data suggest the possibility that active engagement of an individual in his/her therapy (in this case choosing phonological attributes of a target word) may exercise executive functions important for success in treating anomia. Also, continued exploration of task factors that may promote even better treatment effects using this protocol is warranted, as is continued investigation of the neural underpinnings associated with treatment effects.     

Mammalian reovirus, a nonfusogenic nonenveloped virus, forms size-selective pores in a model membrane

During cell entry, reovirus particles with a diameter of 70-80 nm must penetrate the cellular membrane to access the cytoplasm. The mechanism of penetration, without benefit of membrane fusion, is not well characterized for any such nonenveloped animal virus. Lysis of RBCs is an in vitro assay for the membrane perforation activity of reovirus; however, the mechanism of lysis has been unknown. In this report, osmotic-protection experiments using PEGs of different sizes revealed that reovirus-induced lysis of RBCs occurs osmotically, after formation of small size-selective lesions or "pores." Consistent results were obtained by monitoring leakage of fluorophore-tagged dextrans from the interior of resealed RBC ghosts. Gradient fractionations showed that whole virus particles, as well as the myristoylated fragment mu1N that is released from particles, are recruited to RBC membranes in association with pore formation. We propose that formation of small pores is a discrete, intermediate step in the reovirus membrane-penetration pathway, which may be shared by other nonenveloped animal viruses.