The influence of angioplasty balloon sizing on acute post-procedural outcomes: a Finite Element Analysis.

Atherosclerosis is one of the most common vascular pathologies in the world. Among the most commonly performed endovascular treatments, percutaneous transluminal angioplasty (PTA) has been showing significantly positive clinical outcomes. Due to the complex geometries, material properties and interactions that characterize PTA procedures, finite element analyses of acute angioplasty balloon deployment are limited. In this work, finite element method (FEM) was used to simulate the inflation and deflation of a semi-compliant balloon within the 3D model of a stenosed artery with two different plaque types (lipid and calcified). Self-defined constitutive models for the balloon and the plaque were developed based on experimental and literature data respectively. Balloon deployment was simulated at three different inflation pressures (10, 12 and 14 atm) within the two plaque types. Balloon sizing influence on the arterial elastic recoil obtained immediately after PTA was then investigated. The simulated results show that calcified plaques may lead to higher elastic recoil ratios compared to lipid stenosis, when the same balloon inflation pressures are applied. Also, elastic recoil increases for higher balloon inflation pressure independent of the plaque type. These findings open the way for a data-driven assessment of angioplasty balloon sizing selection and clinical procedures optimization.Clinical Relevance- The FE model developed in this work aims at providing quantitative evaluation of recoil after balloon angioplasty. It may be useful for both manufacturers and clinicians to improve efficiency of angioplasty balloon device design and sizing selection with respect to plaque geometry and constitution, consequently enhancing clinical outcomes.

Association of a novel polymorphism in the bovine PPARGC1A gene with growth, slaughter and meat quality traits in Brangus steers.

The PPARGC1A gene (peroxysome proliferator-activated receptor-gamma coactivator 1alpha gene) controls muscle fiber type and brown adipocyte differentiation; therefore, it is a candidate gene for beef quality traits (tenderness and fat content). Two SNPs (Single Nucleotide Polymorphisms) were identified within exon 8 by multiple alignment of DNA sequences obtained from 24 bulls: a transition G/A (SNP 1181) and a transversion A/T (SNP 1299). The SNP 1181 is a novel SNP, corresponding to a non-conservative substitution (AGT/AAT) that could be the cause of amino acid substitution ((364)Serine/(364)Asparagine). A Mismatch PCR method was designed to determine genotypes of 73 bulls and 268 steers for SNP 1181. Growth, slaughter and meat quality information were available for the group of steers. Allele A of SNP 1181 was not found in Angus. In 243 steers, no significant differences (P > 0.05) were found for either final live body weight, gain in backfat thickness in Spring, kidney fat weight, kidney fat percentage, Warner-Bratzler shear force at 7 days postmortem, intramuscular fat percentage or meat colour between genotype GG and AG. This SNP could be included in breed composition and population admixture analyses because there are marked differences in allelic frequencies between Bos taurus and Bos indicus breeds.

Alternatively polyadenylated calpastatin transcripts in bovine muscles / Transcriptos alternativamente poliadenilados de calpastatina en músculos de bovino

Calpastatin activity has a key role in the tenderization process that occurs during postmortem storage of meat under refrigerated conditioning. The regulation of calpastatin (CAST) expression is highly complex, the gene has four putative promoters and at least three different polyadenylation sites, and it is also alternatively spliced. We investigated the presence of alternative polyadenylation (APA) isoforms of CAST transcripts in three muscles (infraspinatus, triceps brachii and semitendinosus) of two bovine breeds (Angus and Brahman). The 3´ RACE-PCR was used to specifically amplify the different APA sites. The amplified fragments were cloned and sequenced. Sequencing confirmed the existence of three expected polyadenylation sites corresponding to short, medium and long polyadenylated transcripts. Also, transcripts with a novel APA site were found in the three muscles of both breeds. Because the same APAs isoforms were found between muscles and breeds, we could hypothesize a possible contribution to the relative abundance of different isoforms, probably in coordination with promoter preference and alternative splicing. This knowledge would be useful in the design of future experiments to analyze differential expression of CAST isoforms and their contribution to the definition of beef tenderness.

La actividad de la calpastatina tiene un rol clave en el proceso de tiernización postmortem de la carne durante su almacenamiento refrigerado. La regulación de la expresión de calpastatina (CAST) es altamente compleja; el gen tiene cuatro potenciales promotores, diferentes sitios de poliadenilación de transcriptos y también splicing alternativo. En este trabajo se investiga la presencia de isoformas de transcriptos de CAST alternativamente poliadenilados (APA) en tres músculos (infraspinatus, triceps brachii y semitendinosus) de dos razas bovinas (Angus y Brahman). Se utilizó la técnica de 3´ RACE-PCR para amplificar específicamente los diferentes sitios APA. Los fragmentos amplificados fueron clonados y secuenciados. La secuenciación confirmó la existencia de tres sitios de poliadenilación conocidos. Un nuevo sitio APA fue identificado en transcriptos de los tres músculos y en ambas razas. Dado que cualitativamente no hubo variación en la presencia de isoformas definidas por APA entre músculos y razas de terneza contrastante, podría hipotetizarse una posible contribución a la abundancia relativa de distintas isoformas, probablemente en forma coordinada con la elección de promotores y el splicing alternativo. Este nuevo conocimiento podría ser de utilidad para el diseño de experimentos de análisis de expresión diferencial de isoformas de calpastatina, para ponderar la contribución de las mismas a las variaciones en terneza de la carne.

Delayed effects of a migrated foreign body (sewing needle) in the cervical spine: a case report.

STUDY DESIGN: A case report is presented. OBJECTIVE: This report documents one case of intraspinal migration of a metal foreign body. SUMMARY OF BACKGROUND DATA: The migration and penetration of foreign bodies into the spine have been described, but there are only three reports of a needle as the causative object. METHODS: This case report included a chart review, an examination of the patient, and a literature search. RESULTS: The patient successfully underwent surgery, in which the foreign body (a sewing needle) was removed. CONCLUSION: It is important to be aware of the possible delayed penetration of a foreign body into the spine even in patients with few or no symptoms.

Utilization of one hundred subcutaneous reservoirs in neurosurgery.

The authors report the use of one hundred subcutaneous reservoirs in eighty nine patients. The various utilizations of the reservoirs correspond to the encountered diseases.

Hematomyelia during anticoagulant therapy.

An unusual case of hematomyelia during anticoagulant therapy is reported in a patient after cardiac surgery. A review of the pertinent literature is presented. After medical and surgical treatment, the transverse symptoms largely subsided with rehabilitation of the patient.

Transpedicular decompression and stabilization of burst fractures of the lumbar spine.

Twenty-seven consecutive patients with neurological impairment due to burst fractures of the lumbar spine were operated upon, via the postero-lateral route, over a 38-month-period. Transpedicular fixation devices [posterior segmental fixator (PSF) or variable screw placement system (VSP)] were applied in all cases, in order to achieve short-segment fusion of the fractured spinal segment. Return to useful motor power or neurological normality (median follow-up: 18.7 months) occurred in 22 cases (81% of the whole series), with this outcome resulting in all but one of the cases with preoperative incomplete neurological deficit. Postoperative encroachment of the spinal canal, degree of kyphotic deformity, and reduction of the vertebral height showed statistically significant differences compared with the corresponding preoperative values.

Delayed worsening of the surgical correction of angular and axial deformity consequent to burst fractures of the thoracolumbar or lumbar spine.

Forty-one patients with burst fractures of the thoracolumbar junction, or the lumbar spine (T12 to L5), were followed for 6-48 months (mean follow-up = 19.9 months) after early surgery (usually within 24 hours). Preoperative, early postoperative, and late postoperative degrees of kyphosis, as well as percent reduction of the height of the vertebral body were calculated and compared. Early postoperative radiologic evaluations showed a statistically significant difference (p < 0.0001) between the mean values of both parameters calculated respectively before and after surgery. The decrease of the surgical correction, from the initial postoperative radiographs to follow-up, was statistically significant (p < 0.0001). However, the final values were better when compared with the preoperative features (p < 0.003 and p < 0.0001, respectively for degree of kyphosis and reduction in vertebral height.

An evaluation of nurse rostering practices in the National Health Service.

An evaluation of nurse rostering practices in the National Health Service The scheduling of nursing time on hospital wards is critical to the delivery of patient care, resource utilization and employee satisfaction. Over the past decade many hospital wards in the United Kingdom (UK) have moved away from the traditional planning of rosters by a single manager, towards more participative processes known as self-rostering and team rostering. This paper tests the hypothesis, developed from the literature, that the three types of rostering approach may be positioned along a continuum. Self-rostering at one extreme, is conducive to staff empowerment, motivation and roster effectiveness, whilst departmental rostering, at the other, leads to perceived autocracy, reduced empowerment, lower levels of staff motivation and roster effectiveness. Team rostering is positioned mid-way on this continuum. This paper reports the findings of an empirical study of nurse rostering practices in the UK National Health Service (NHS), with a view to developing an understanding of the implications of implementing these three rostering approaches and testing the above hypothesis. The survey of rostering practices in 50 NHS wards, and in-depth case studies of seven wards, revealed that each of the three rostering approaches has benefits and limitations and a picture emerges quite different from that implied by the research hypothesis. Whilst the literature suggests that the choice of rostering approach determines the level of perceived autocracy, staff motivation and roster effectiveness, it is proposed in this paper that selection of rostering approach should be contingent upon operational context. The paper concludes with a framework which stipulates that the choice of rostering approach for a ward should be determined on the basis of four contingent variables, namely, ward size, demand variability, demand predictability, and complexity of skill mix. It is recommended that departmental rostering be applied in large wards with complex rostering problems, whilst team rostering is more appropriate for medium sized wards, and self-rostering appropriate for small wards.

Can lacerations of the thoraco-lumbar dura be predicted on the basis of radiological patterns of the spinal fractures?

Encroachment upon the spinal canal, separation of the pedicles, associated fractures of the laminae are assumed to be related to dural lacerations consequent to burst fractures of the thoracolumbar spine. Owing to the possible occurrence of early or delayed complications of meningeal discontinuations, the predictive value of these signs has been analyzed in a consecutive series of 50 patients, who were submitted to surgery. Dural tears were found to occur at a rate of 60%, without any statistically significant relation with any of the examined signs. The results were not consistent with the thesis that lacerations of the dura can be predicted on the basis of radiological signs.

Near-anatomical reduction and stabilization of burst fractures of the lower thoracic or lumbar spine.

Thirty-one consecutive symptomatic patients with burst fractures of the lower thoracic or lumbar spine (T 11-L4) were treated by early surgery in a 36-month period, with near-anatomical reduction being achieved via the postero-lateral route. Fusion and reconstruction of the vertebral body was done by using autologous or processed bovine bone. Correction of the kyphotic deformity was obtained by using distraction rods or transpedicular devices. The post-operative mean degree of kyphosis, percent vertebral height, and percent canal stenosis showed statistically significant differences, compared with the corresponding pre-operative mean values. All but one of the 25 patients with incomplete paraplegia exhibited neurological improvement, with complete recovery occurring in 20 cases (median follow-up: 16 months) irrespective of the location of the lesion at the thoraco-lumbar junction (T 11-L1) or the lower lumbar segment (L2-L4). Out of the 6 patients with pre-operative complete paraplegia, useful motor power returned in one case with a lesion below L1. The results confirm the suitability of the postero-lateral route and are consistent with the assumption that early near-anatomical reduction and stabilization favours maximum neurological recovery in symptomatic patients.

Giant fusiform aneurysm in middle cerebral artery branches: a report of two cases and a review of the literature.

Giant fusiform aneurysm (2.5 cm in length or more) is an unusual pathological entity typically described involving the main trunks of cerebral arteries and, rarely, cerebral artery branches. We are presenting two cases of middle cerebral artery branch giant fusiform aneurysm, one surgically and the other conservatively treated. We were unable to find in the literature reports of similar aneurysms at the same location. Clinical and pathological aspects, radiological findings, and treatment are discussed.

Spinal cord stimulation for the treatment of progressive systemic sclerosis and Raynaud's syndrome.

Progressive Systemic Scleroderma (PSS) is a generalized disease of connective tissue involving the skin, as well as other internal organs. The cutaneous signs are characterized by a progressive sclerosis and loss of function or dexterity in the hands. Between 1987 and 1992, 15 patients affected by scleroderma were treated by means of spinal cord stimulation (SCS) in order to reduce signs and symptoms related to vascular damage. The follow-up ranged from 12 months to 6 years. The study confirms that SCS is an effective therapy in patients with PSS and Raynaud's phenomenon because of its beneficial effects on the Raynaud episodes, ulcers, pain, vascular sclerosis and hand function. This method may have a primary role in the treatment of this chronic disorder because of the high probability of failure of other medical or surgical therapy.

Metoclopramide increases plasma but not cerebrospinal fluid vasopressin levels in man: study in hydrocephalic patients.

Arginine vasopressin (AVP) concentrations were determined in plasma and in cerebrospinal fluid (CSF) in 8 adult male patients suffering from hydrocephalus of various etiologies, before and after intravenous administration of 10 mg metoclopramide. Metoclopramide was able to increase the plasma (2.6 +/- 0.2 ng/l in basal conditions and 6.1 +/- 0.6 ng/l at 30 min) but not the CSF AVP levels. The results suggest that the neurons which secrete AVP into the CSF may be functionally different from those secreting into the peripheral circulation.

On the predictive value of radiological signs for the presence of dural lacerations related to fractures of the lower thoracic or lumbar spine.

The predictive value of radiological signs for the presence of lacerations of the thoracolumbar dura in spine-injured patients could represent an important adjunct to the rationale for the optimal management, owing to the possible onset of early or delayed complications of these lesions. Occurrence of signs assumed to be related to dural tears, such as separation of the pedicles, fractures of the laminae, and encroachment of the spinal canal, was analyzed in a consecutive series of 25 patients submitted to surgical reduction and stabilization of the fractured lower thoracic or lumbar spine in a 24-month period. No statistically significant correlation was found between dural lacerations and any of the examined signs. Leaks of cerebrospinal fluid through traumatic breachs of the meninges were found in 16 of the 25 cases. The high rate of occurrence of dural lesions associated with fractures of the lower thoracic or lumbar spine adds a further argument to the aggressive approach to these injuries.

Spinal subarachnoid hematoma of unknown etiology. A case report.

A case of spinal subarachnoid hematoma at T3-T7 level is reported in a 60-year-old hunter, who developed progressive spinal cord impairment after receiving the recoil of his shotgun. Both clinical and neuroradiological investigations, including the selective spinal angiography, failed to demonstrate the origin of the bleeding. The combination of an apparently trivial spinal trauma with temporary increase of the intrathoracic pressure might be considered as possible etiologic factor.

Correlates of adaptation to the sleep laboratory. Behavior, sleep organization, quantitative EEG.

The present study aims at establishing to what extent adaptation phenomena should be taken into consideration for the definition of an independent baseline in sleep research. To this purpose we have studied: (1) a standard battery of neuropsychological test evaluating performance, subjective assessments of moods and sleep quality; (2) classical sleep parameters; (3) data derived from quantitative analysis of sleep EEG. 19 young male volunteers have been recorded for consecutive nights; 7 of them underwent the recordings for 3, 8 for 6 and 4 for 10 nights. Results can be summarized as follows: (A) both interindividual and intraindividual variability show a progressively decreasing trend toward homogeneity for most of the explored parameters; (B) steady state is reached in different times for different groups of parameters; (C) an adequate group homogeneity was achieved from the 5th night onwards. Implications of these data in sleep studies, namely in sleep active drug research are discussed.

Calcification and ossification of the spinal arachnoid after intrathecal administration of Depo-Medrol.

A woman 38-year-old, suffering for about ten years from multiple sclerosis and treated with repeated therapy cycles of intrathecal Depo-Medrol, developed a spastic paraparesis at the lower limbs. A lumbar myelography was carried out, and a dorsal block was demonstrated. The patient underwent a dorsal laminectomy, and arachnoidal calcification and ossification was find, but the removal of the bone plaques was ineffectual in order to the subsequent course of the neurological troubles. The results of the histological study and chemical tests are reported, and the etiology and the pathogenesis are discussed on the basis of the pertinent literature.