Trapezial space height measurement after trapeziectomy: a comparison of the use of standard and stress radiographs

PURPOSE: To assess whether the behavior of the trapezial space under stress after excision of the trapezium and insertion of a K-wire to hold the thumb metacarpal base away from the distal pole of the scaphoid for 4 weeks is improved by either palmaris longus interposition or ligament reconstruction (LRTI). METHODS: The trapezial space height and trapezial space ratios were assessed on 50 pairs of standard and stress views obtained 1 year after trapeziectomy. Seventeen of the 50 thumbs had simple trapeziectomy, 15 had trapeziectomy plus LRTI and 18 had trapeziectomy with palmaris longus tendon interposition. The reproducibility of these measurements also was assessed. RESULTS: The 95% limits of agreement for intra- and interobserver differences in the measurement of the trapezial space height were -1 to +1 mm and -2 to +1 mm, respectively. The mean differences between the trapezial heights on the standard and stress radiographs were 1.6 mm (SD, 2.5) for simple trapeziectomy, 1.2 mm (SD, 3.1) for trapeziectomy and LRTI, and 1.2 mm (SD, 2.4) for trapeziectomy with interposition of palmaris longus. The differences between the trapezial space height and trapezial space ratios on the standard and stress radiographs after the 3 different surgeries were not notably different. CONCLUSIONS: Neither the creation of a suspensory ligament nor palmaris longus tendon interposition, as opposed to the isolated placement of a K-wire across the trapezial void for 4 weeks, alters the behavior of the trapezial space under stress at the 1-year follow-up examination. It is thus appropriate to use standard radiographs at the 1-year follow-up examination to assess and compare the trapezial space after these different techniques of trapeziectomy.     

Novel treatment of atrophic rhinitis: early results

The aim of this randomized control trial, performed at a tertiary referral hospital, was to compare the therapeutic effectiveness of two novel treatment modalities, oral rifampicin and submucosal placentrex injection, in randomly selected patients of primary atrophic rhinitis regarding objective, subjective and histopathological improvement. Patients treated with oral rifampicin showed most promising results regarding objective, subjective and histopathological improvement with maximum disease-free interval on regular follow-up as compared to submucosal placentrex injections.     

Combined use of impella device and intra‐aortic balloon pump to improve survival in a patient in profound cardiogenic shock post cardiac arrest

Patients who suffer cardiogenic shock after cardiac arrest have a very poor prognosis. Left ventricular assist devices have proven to be useful in these patients to improve survival. Recently introduced percutaneous assist devices are easier to use and can be inserted quickly in the catheterization laboratory. We describe a case where intra‐aortic balloon pump by itself was not enough to provide hemodynamic support in a patient with cardiogenic shock after cardiac arrest. The Impella Recover^® LP 2.5 system (ABIOMED, Inc., Danvers, MA) was successfully used along with the balloon pump for hemodynamic support and resulted in dramatic improvement of the patient's condition. © 2009 Wiley‐Liss, Inc.     

Stem cell therapy for critical limb ischaemia — a review

Critical limb ischaemia is an intractable condition associated with high levels of amputation, leading to a low quality of life and increased morbidity and mortality. It is often not treatable by standard therapeutic modalities. Neoangiogenesis has been proposed as a novel method of treatment of such patients. Vascular endothelial growth factor (VEGF) and cytokine fibroblast growth factor (FGF-1) have been shown to elicit neoangiogenesis. Stem cells are progenitor cells which can differentiate in vivo into different types of cells. Mesenchymal stem cells (MSCs) are a type of adult stem cells which have an immunomodulatory effect. Stem cell therapy has been used in animal studies to improve limb vascularity in rat and rabbit models. Several clinical studies have also validated their use for critical limb ischaemia. However many issues are still unresolved. These include the dosage, delivery and safety issues in relation to stem cell therapy. However stem cells are likely to be an important therapeutic modality to treat critical limb ischaemia in the near future.     

Release of pig leukocytes and reduced human NK cell recruitment during ex vivo perfusion of HLA‐E/human CD46 double‐transgenic pig limbs with human blood

Background

In pig‐to‐human xenotransplantation, interactions between human natural killer (NK) cells and porcine endothelial cells (pEC) are characterized by recruitment and cytotoxicity. Protection from xenogeneic NK cytotoxicity can be achieved in vitro by the expression of the non‐classical human leukocyte antigen‐E (HLA‐E) on pEC. Thus, the aim of this study was to analyze NK cell responses to vascularized xenografts using an ex vivo perfusion system of pig limbs with human blood.

Methods

Six pig forelimbs per group, respectively, stemming from either wild‐type (wt) or HLA‐E/hCD46 double‐transgenic (tg) animals, were perfused ex vivo with heparinized human blood for 12 hours. Blood samples were collected at defined time intervals, cell numbers counted, and peripheral blood mononuclear cells analyzed for phenotype by flow cytometry. Muscle biopsies were analyzed for NK cell infiltration. In vitro NK cytotoxicity assays were performed using pEC derived from wt and tg animals as target cells.

Results

Ex vivo, a strong reduction in circulating human CD45 leukocytes was observed after 60 minutes of xenoperfusion in both wt and tg limb groups. NK cell numbers dropped significantly. Within the first 10 minutes, the decrease in NK cells was more significant in the wt limb perfusions as compared to tg limbs. Immunohistology of biopsies taken after 12 hours showed less NK cell tissue infiltration in the tg limbs. In vitro, NK cytotoxicity against hCD46 single tg pEC and wt pEC was similar, while lysis of double tg HLA‐E/hCD46 pEC was significantly reduced. Finally, circulating cells of pig origin were observed during the ex vivo xenoperfusions. These cells expressed phenotypes mainly of monocytes, B and T lymphocytes, NK cells, as well as some activated endothelial cells.

Conclusions

Ex vivo perfusion of pig forelimbs using whole human blood represents a powerful tool to study humoral and early cell‐mediated rejection mechanisms of vascularized pig‐to‐human xenotransplantation, although there are several limitations of the model. Here, we show that (i) transgenic expression of HLA‐E/hCD46 in pig limbs provides partial protection from human NK cell‐mediated xeno responses and (ii) the emergence of a pig cell population during xenoperfusions with implications for the immunogenicity of xenografts.     

Template synthesis of multifunctional nanotubes for controlled release.

In the past few decades, nanoscale materials have been widely used for controlled release applications. Importantly, many researches have focused on multifunctional nanoparticles for targeted delivery of bioactive and imaging agents as therapeutics and diagnostics. Recent advances in nanotechnology have made possible the design and development of tubular nanoscale particles called nanotubes. The tubular shape of such particles is highly attractive since it is possible to differentially functionalize the inner and outer surfaces to facilitate drug loading, biocompatibility and biorecognition. Novel synthetic strategies allow the fabrication of tubular structures with well-defined diameters and lengths. This can have important implications in biodistribution, subcellular trafficking and drug release. In this article the biomedical applications of nanotubes will be discussed with emphasis on the template synthesis of composite nanotubes containing silica and iron oxide that have potential use in drug delivery, magnetic resonance imaging (MRI), and chemical and biochemical separations.     

Targetable water-soluble polymer-drug conjugates for the treatment of visceral leishmaniasis.

The present work describes the synthesis, characterization, and biological evaluation of targetable N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-anti-leishmanial drug conjugates for the treatment of visceral leishmaniasis (VL). Conjugates of HPMA copolymer with NPC1161, an 8-aminoquinoline analog with anti-leishmanial activity, containing N-acetylmannosamine (ManN) in the side chains were synthesized and characterized. In vitro anti-leishmanial efficacy of the conjugates was determined in mouse peritoneal macrophages infected with Leishmania donovani amastigotes. The conjugates were tested against mammalian KB cells for cytotoxicity. The effect of ManN content on uptake was evaluated in RAW 264 murine macrophages. In vivo anti-leishmanial efficacy was evaluated at 1 mg/kg intravenous dose in BALB/c mice. HPMA copolymer-NPC1161 conjugates with 5 mole% or higher ManN content were significantly (p<0.0001) more active (ED50<15 microg/ml) than nontargeted conjugates (ED50>30 microg/ml). All conjugates were relatively nontoxic towards the mammalian cells. Significantly (p<0.003) higher uptake was observed for targeted conjugates compared to nontargeted conjugates. The targeted conjugates were significantly more effective in vivo (67-80% inhibition, p<0.0001) than nontargeted conjugate (47% inhibition). HPMA copolymers containing ManN in the side chains can potentially reduce the toxicity and increase efficacy of anti-leishmanial drugs for the treatment of VL.     

Bispectral index correlates well with Richmond agitation sedation scale in mechanically ventilated critically ill patients

Purpose  

The clinical sedation scores available for assessing sedation in the intensive care unit (ICU) have drawbacks and limit their usefulness in paralyzed and deeply sedated patients. An objective tool, the bispectral index (BIS), could prove beneficial in such circumstances. We evaluated the ability of BIS to assess the level of sedation and its correlation with the Richmond agitation sedation scale (RASS) in ICU.     

The functional neuroanatomy of thematic role and locative relational knowledge

Lexical-semantic investigations in cognitive neuroscience have focused on conceptual knowledge of concrete objects. By contrast, relational concepts have been largely ignored. We examined thematic role and locative knowledge in 14 left-hemisphere-damage patients. Relational concepts shift cognitive focus away from the object to the relationship between objects, calling into question the relevance of traditional sensory-functional accounts of semantics. If extraction of a relational structure is the critical cognitive process common to both thematic and locative knowledge, then damage to neural structures involved in such an extraction would impair both kinds of knowledge. If the nature of the relationship itself is critical, then functional neuroanatomical dissociations should occur. Using a new lesion analysis method, we found that damage to the lateral temporal cortex produced deficits in thematic role knowledge and damage to inferior fronto-parietal regions produced deficits in locative knowledge. In addition, we found that conceptual knowledge of thematic roles dissociates from its mapping onto language. These relational knowledge deficits were not accounted for by deficits in processing nouns or verbs or by a general deficit in making inferences. Our results are consistent with the hypothesis that manners of visual motion serve as a point of entry for thematic role knowledge and networks dedicated to eye gaze, whereas reaching and grasping serve as a point of entry for locative knowledge. Intermediary convergence zones that are topographically guided by these sensory-motor points of entry play a critical role in the semantics of relational concepts.