Transcatheter valves: a brave New World

Over the past five years, transcatheter valves have stimulated the attention of physicians, engineers, and investors. Transcatheter valve design and implantation techniques depart from the time-proven features of surgical valves, and this has an important impact on the safety and efficacy of prosthetic valve therapy. Herein is reviewed the performance of transcatheter valve procedures in comparison to surgical valves, together with a summary of the specific design features of several emerging transcatheter valves. How the current and future generation transcatheter valves are likely to impact on patient treatment is also explored.     

Non-invasive functional evaluation of the reserve in fatigue and the diaphragm structure using transthoracic echography in B and M modes

The diaphragm is the principal respiratory muscle. Its special characteristics have made it difficult to design instruments capable of performing a non-invasive evaluation of its structure and function in humans. The present study was designed to evaluate the potential use of echography as a non-invasive method to fulfil these objectives.     

The potential value of early screening for neurological deficits in participants in certain sports

Physicians occasionally encounter the punch-drunk syndrome among boxers after longlasting careers characterized by blows to the head. The list of sports leading to punch-drunk syndrome is rapidly increasing, making it a notable public health problem. A lack of specific findings leads to defects in reporting the condition, and consequently to delay in treatment. Although the rigorous enforcement of sport rules and constant improvements of sporting equipment have decreased the occurrence of the syndrome, early detection of punch-drunk syndrome is crucial and would have comprehensive benefits. Two groups of signs and symptoms can be identified: dementia and Parkinsonism. A prompt diagnosis with a correct classification of the suspected cases is crucial. Therefore, we offer an overview of the symptomatology as well as proposing the introduction of a screening method among risk groups based on generic and minute neurological examination and dementia testing.     

Resveratrol may be beneficial in treatment of diabetic foot syndrome

Diabetic foot syndrome (DFS) is a late-stage complication of type 2 diabetes which originates from interplay among impaired tissue regeneration, vasculopathy, neuropathy and inflammation all on the background of insulin resistance. Despite astonishing mortality rate pharmacological approach in management of diabetic ulceration is almost non-existent. Foot pressure relief, wound debridement and infection control remain widely accepted options in the treatment of DFS. We hypothesize that resveratrol treatment and subsequent activation of SIRT1 pathway might be highly beneficial for patients with DFS. This prediction is based on multiple lines of evidence implicating resveratrol and sirtuins in restoration of insulin sensitivity, microcirculation, tissue regeneration, function of peripheral nerves and production of cytokines. Stabilized “nutraceutical” formulations of resveratrol with high absorption rate are essential to examine its potential medical benefits since dietary polyphenols are known to be rapidly metabolized by gut microflora and oxidized during absorption. Clinical trials with nutraceutical formulations and placebo are required to understand if resveratrol indeed holds the promise for treatment of DFS.     

Expression of class 3 semaphorins and their receptors in human breast neoplasia

Staton C A, Shaw L A, Valluru M, Hoh L, Koay I, Cross S S, Reed M W & Brown N J
(2011) Histopathology 59 , 274–282 Expression of class 3 semaphorins and their receptors in human breast neoplasia Aims: This study aimed to identify the involvement of class 3 semaphorins (Sema3) and receptors, neuropilins (Np1 and Np2) and plexins (A1–A4) in breast cancer development and angiogenesis. Methods and results: We quantified and correlated Sema3A, Sema3B, Sema3F and their known receptors and coreceptors Plexin‐A1, Plexin‐A3, Np1 and Np2 in sections of normal human breast, benign and pre‐malignant hyperplastic tissue, pre‐invasive and invasive cancer, and compared these findings with our previously published data on vascular endothelial growth factor (VEGF) and microvessel density (MVD) in the same samples. Histological analysis revealed that Sema3B was expressed more strongly and widely than Sema3A and 3F in normal breast tissue and all three semaphorins decreased with the transition from in situ to invasive cancer (P < 0.014). Plexin‐A3 decreased significantly with progression towards invasive cancer (P < 0.045), whereas Plexin‐A1 expression was only significantly reduced once invasion had occurred (P = 0.012). Np1 and Np2 were expressed in both endothelial and epithelial/tumour cells. Np2 expression did not change, but Np1 expression significantly increased in the spectrum from hyperplasia to ductal carcinoma in situ (P < 0.035), but decreased with invasive cancer. Conclusion: These data suggest that a decrease in class 3 semaphorin and their plexin receptors have some relationship with disease progression in ductal breast carcinoma.     

Postoperative intra-arterial methylene blue injection of colorectal cancer specimens increases the number of lymph nodes recovered

Törnroos A, Shabo I, Druvefors B, Arbman G & Olsson H
(2011) Histopathology 58 , 408–413
Postoperative intra‐arterial methylene blue injection of colorectal cancer specimens increases the number of lymph nodes recovered Aims: To determine the possible advantage of intra‐arterial injection of methylene blue with a view to improving lymph node recovery in postoperative examination of colorectal cancer specimens. Methods and results: Thirty‐two colorectal cancer specimens were assigned randomly to either dissection with intra‐arterial methylene blue injection or to routine dissection (without methylene blue injection). Immediately postoperatively, the specimens in the staining group were injected intra‐arterially with methylene blue dye. The two procedures were compared with respect to the number of lymph nodes recovered. The number of recovered lymph nodes was significantly higher in the intra‐arterial methylene blue injection group than in the group investigated with routine procedures (P < 0.0001). Conclusion: The intra‐arterial methylene blue injection method is fairly easy to use postoperatively and increases significantly the number of lymph nodes recovered in colorectal cancer specimens.     

Biological significance of 5S rRNA import into human mitochondria: role of ribosomal protein MRP-L18

5S rRNA is an essential component of ribosomes of all living organisms, the only known exceptions being mitochondrial ribosomes of fungi, animals, and some protists. An intriguing situation distinguishes mammalian cells: Although the mitochondrial genome contains no 5S rRNA genes, abundant import of the nuclear DNA-encoded 5S rRNA into mitochondria was reported. Neither the detailed mechanism of this pathway nor its rationale was clarified to date. In this study, we describe an elegant molecular conveyor composed of a previously identified human 5S rRNA import factor, rhodanese, and mitochondrial ribosomal protein L18, thanks to which 5S rRNA molecules can be specifically withdrawn from the cytosolic pool and redirected to mitochondria, bypassing the classic nucleolar reimport pathway. Inside mitochondria, the cytosolic 5S rRNA is shown to be associated with mitochondrial ribosomes.