Nanobiomaterial applications in orthopedics.

Advancements in nanobiotechnology are revolutionizing our capability to understand biological intricacies and resolve biological and medical problems by developing subtle biomimetic techniques. Nanocomposites and nanostructured materials are believed to play a pivotal role in orthopedic research since bone itself is a typical example of a nanocomposite. This article reviews current strategies using nanobiomaterials to improve current orthopedic materials and examines their applications in bone tissue engineering. Preliminary investigations support the potential of nanobiomaterials in orthopedic applications; however, significant advancements are necessary to achieve clinical use. Overall, current trends in nanobiotechnology foreshadow a bright future through the use of nanobiomaterials in the orthopedic domain.     

Sexual limitations in people living with Parkinson's disease

Objectives: To explore disease sequelae and usage of support services in people living with Parkinson's disease (PD). Methods: A 31‐item survey was administered to a convenience sample of people with PD recruited through Parkinson's NSW Inc. and its support groups. Results: Four hundred and forty‐four responses were received. Sexual limitations were reported by 73.5% of people with PD. Additionally, respondents indicated that health professionals did not necessarily understand what it is like to live with the disease. Conclusions: Movement problems are most often presented as the major sequelae of PD. This study shows that for a large proportion of sufferers, sexual limitations are an issue. Additionally, it is important for health professionals to provide ample opportunity for the discussion of these difficulties.     

Induction of angiogenesis in tissue-engineered scaffolds designed for bone repair: a combined gene therapy-cell transplantation approach

One of the fundamental principles underlying tissue engineering approaches is that newly formed tissue must maintain sufficient vascularization to support its growth. Efforts to induce vascular growth into tissue-engineered scaffolds have recently been dedicated to developing novel strategies to deliver specific biological factors that direct the recruitment of endothelial cell (EC) progenitors and their differentiation. The challenge, however, lies in orchestration of the cells, appropriate biological factors, and optimal factor doses. This study reports an approach as a step forward to resolving this dilemma by combining an ex vivo gene transfer strategy and EC transplantation. The utility of this approach was evaluated by using 3D poly(lactide-co-glycolide) (PLAGA) sintered microsphere scaffolds for bone tissue engineering applications. Our goal was achieved by isolation and transfection of adipose-derived stromal cells (ADSCs) with adenovirus encoding the cDNA of VEGF. We demonstrated that the combination of VEGF releasing ADSCs and ECs results in marked vascular growth within PLAGA scaffolds. We thereby delineate the potential of ADSCs to promote vascular growth into biomaterials.     

Difference vectors to describe dynamics of the ST segment and the ventricular gradient in acute ischemia

Background

The ECG is important in the diagnosis and triage of the acute coronary syndrome (ACS), especially in the hyperacute phase, the “golden hours,” during which myocardial salvage possibilities are largest. An important triaging decision to be taken is whether or not a patient requires primary PCI, for which, as mentioned in the guidelines, the presence of an ST elevation (STE) pattern in the ECG is a major criterion. However, preexisting non-zero ST amplitudes (diagnostic, but also non-diagnostic) can obscure or even preclude this diagnosis.

Methods

In this study, we investigated the potential diagnostic possibilities of ischemia detection by means of changes in the ST vector, ΔST, and changes in the VG (QRST integral) vector, ΔVG. We studied the vectorcardiograms (VCGs) synthesized of the ECGs of 84 patients who underwent elective PTCA. Mean ± SD balloon occlusion times were 260 ± 76 s. The ECG ischemia diagnosis (ST elevation, STE, or non-ST-elevation, NSTE), magnitudes and orientations of the ST and VG vectors, and the differences ΔST and ΔVG with the baseline ECG were measured after 3 min of balloon occlusion.

Results

Planar angles between the ΔST and ΔVG vectors were 14.9 ± 14.0°. Linear regression of ΔVG on ΔST yielded ΔVG = 324·ΔST (r = 0.85; P < 0.0001, ΔST in mV). We adopted ΔST > 0.05 mV, and the corresponding ΔVG > 16.2 mV·ms as ischemia thresholds. The classical criteria characterized the ECGs of 46/84 (55%) patients after 3 min of occlusion as STE ECGs. Combined application of the ΔST and ΔVG criteria identified 73/84 (87%) of the patients as ischemic.

Conclusion

Differential diagnosis by ΔST and ΔVG (requiring an earlier made non-ischemic baseline ECG) could dramatically improve ECG guided detection of patients who urgently require catheter intervention.     

Semantic monitoring of words with emotional connotation during fMRI: contribution of anterior left frontal cortex.

Previous studies showed that cortex in the anterior portions of the left frontal and temporal lobes participates in generating words with emotional connotations and processing pictures with emotional content. If these cortices process the semantic attribute of emotional connotation, they should be active whenever processing emotional connotation, without respect to modality of input or mode of output. Thus, we hypothesized that they would activate during monitoring of words with emotional connotations. Sixteen normal subjects performed semantic monitoring of words with emotional connotations, animal names, and implement names during fMRI. Cortex in the anterior left frontal lobe demonstrated significant activity for monitoring words with emotional connotations compared to monitoring tone sequences, animal names, or implement names. Together, the current and previous results implicate cortex in the anterior left frontal lobe in semantic processing of emotional connotation, consistent with connections of this cortex to paralimbic association areas. Current findings also indicate that neural substrates for processing emotional connotation are independent of substrates for processing the categories of living and nonliving things.     

A critical review of the safety and antiemetic efficacy of delta-9-tetrahydrocannabinol

Over the past six years, both government institutions and private enterprise have expressed great interest and activity in the isolation of chemical constituents from the Cannabis sativa plant and synthesis of novel cannabinoid compounds with potential medicinal uses. Evaluation of the safety and antiemetic efficacy of delta-9-tetrahydrocannabinol, the primary psychoactive cannabinoid component of marijuana, comprises one of several very active areas of cannabinoid clinical research. The results of clinical studies of the safety and antiemetic efficacy of delta-9-tetrahydrocannabinol in patients receiving cancer chemotherapy are critically evaluated. Deficiencies in current knowledge of the clinical pharmacology of delta-9-tetrahydrocannabinol are discussed in the context of antiemetic drug evaluation.     

Immunoglobulins and dietary protein antibodies in childhood coeliac disease

Twenty-four children with coeliac disease were compared with a control group, comprising 17 children with a variety of gastroenterological disorders, with respect to serum immunoglobulins and dietary protein antibodies. Elevated levels of IgA and abnormally low levels of IgM were demonstrated in one third of the coeliac patients. Antibodies to at least one of eight dietary proteins were found in 50% of coeliac children. Three children with raised levels of serum IgA and two with deficient IgM were re-examined after varying periods on a gluten-free diet. Antibodies to dietary proteins had waned and immunoglobulin levels returned to normal in all cases. The raised IgA was considered to have resulted from an extensive immunological response to antigens of dietary origin which had entered through the abnormal gut mucosa. It is suggested that IgM deficiency was due to specific inhibition of IgM synthesis by dietary components which had also entered through the mucosa.