[Artificial intravascular oxygenation (IVOX). Application to the treatment of postoperative respiratory failure]

Very recently, the concept of artificial intracorporeal oxygenation of blood for patients suffering from respiratory failure has been introduced into clinical practice through development of a totally implantable intravascular oxygenator (IVOX). We report on the use of such a device in a patient who developed severe respiratory insufficiency secondary to prolonged hypovolaemic shock and pneumonia following successful repair of a ruptured abdominal aortic aneurysm in September, 1990. Postoperatively, severe hypoxaemia occurred (AaDO2 548-602 torr) despite extensive mechanical ventilatory support. There was no obvious chance to overcome this situation by conventional therapeutic measures and the decision was made to institute IVOX therapy. Hypoxaemia was resolved immediately and both FiO2 and tidal volume could be reduced within hours. The patient's respiratory condition continued to improve over the next days leading to termination of IVOX therapy after 71 hours. However, the necessity of long-term ventilatory support secondary to recurrent pneumonia and sepsis, multiple abdominal reoperations for ischemic colitis and retroperitoneal abscess prolonged his recovery. He was discharged from the hospital after four months and is alive and well now 14 months after his operation. He is the first long-term survivor after IVOX therapy in Europe. IVOX may be successfully used in selected patients while the indications and it's potential role in the therapy of severe respiratory failure still need to be defined.

[Dens invaginatus. Review of the literature and diagnostic and therapeutic guidelines]

Dens invaginatus is a clinically relevant malformation of teeth resulting from an infolding of enamel and dentine into the dental structure during tooth formation, hence the former denomination "dens in dente". The dens invaginatus shows multiple morphological variations of crown and root formation. This frequently leads to caries, pulpal and periodontal involvement with necrosis and loss of attachment. Therefore, early diagnosis and prevention are of utmost importance. Due to the complexity of the malformation, treatment options in former days were limited. This article presents a profound review of the literature regarding etiology, epidemiology and histology. It discusses clinical appearance and diagnosis and it provides guidelines for decision-making and treatment of invaginated teeth.

Novel cell-free strategy for therapeutic angiogenesis: in vitro generated conditioned medium can replace progenitor cell transplantation

BACKGROUND: Current evidence suggests that endothelial progenitor cells (EPC) contribute to ischemic tissue repair by both secretion of paracrine factors and incorporation into developing vessels. We tested the hypothesis that cell-free administration of paracrine factors secreted by cultured EPC may achieve an angiogenic effect equivalent to cell therapy. METHODOLOGY/PRINCIPAL FINDINGS: EPC-derived conditioned medium (EPC-CM) was obtained from culture expanded EPC subjected to 72 hours of hypoxia. In vitro, EPC-CM significantly inhibited apoptosis of mature endothelial cells and promoted angiogenesis in a rat aortic ring assay. The therapeutic potential of EPC-CM as compared to EPC transplantation was evaluated in a rat model of chronic hindlimb ischemia. Serial intramuscular injections of EPC-CM and EPC both significantly increased hindlimb blood flow assessed by laser Doppler (81.2+/-2.9% and 83.7+/-3.0% vs. 53.5+/-2.4% of normal, P<0.01) and improved muscle performance. A significantly increased capillary density (1.62+/-0.03 and 1.68+/-0.05/muscle fiber, P<0.05), enhanced vascular maturation (8.6+/-0.3 and 8.1+/-0.4/HPF, P<0.05) and muscle viability corroborated the findings of improved hindlimb perfusion and muscle function. Furthermore, EPC-CM transplantation stimulated the mobilization of bone marrow (BM)-derived EPC compared to control (678.7+/-44.1 vs. 340.0+/-29.1 CD34(+)/CD45(-) cells/1x10(5) mononuclear cells, P<0.05) and their recruitment to the ischemic muscles (5.9+/-0.7 vs. 2.6+/-0.4 CD34(+) cells/HPF, P<0.001) 3 days after the last injection. CONCLUSIONS/SIGNIFICANCE: Intramuscular injection of EPC-CM is as effective as cell transplantation for promoting tissue revascularization and functional recovery. Owing to the technical and practical limitations of cell therapy, cell free conditioned media may represent a potent alternative for therapeutic angiogenesis in ischemic cardiovascular diseases.

Class-switzched B cells display response to therapeutic B-cell depletion in rheumatoid arthritis

Introduction Reconstitution of peripheral blood (PB) B cells after therapeutic depletion with the chimeric anti-CD20 antibody rituximab (RTX) mimics lymphatic ontogeny. In this situation, the repletion kinetics and migratory properties of distinct developmental B-cell stages and their correlation to disease activity might facilitate our understanding of innate and adaptive B-cell functions in rheumatoid arthritis (RA). Methods Thirty-five 'RTX-naïve' RA patients with active arthritis were treated after failure of tumour necrosis factor blockade in an open-label study with two infusions of 1,000 mg RTX. Prednisone dose was tapered according to clinical improvement from a median of 10 mg at baseline to 5 mg at 9 and 12 months. Conventional disease-modifying antirheumatic drugs were kept stable. Subsets of CD19+ B cells were assessed by flow cytometry according to their IgD and CD27 surface expression. Their absolute number and relative frequency in PB were followed every 3 months and were determined in parallel in synovial tissue (n = 3) or synovial fluid (n = 3) in the case of florid arthritis. Results Six of 35 patients fulfilled the European League Against Rheumatism criteria for moderate clinical response, and 19 others for good clinical response. All PB B-cell fractions decreased significantly in number (P < 0.001) after the first infusion. Disease activity developed independently of the total B-cell number. B-cell repopulation was dominated in quantity by CD27-IgD+ 'naïve' B cells. The low number of CD27+IgD- class-switched memory B cells (MemB) in the blood, together with sustained reduction of rheumatoid factor serum concentrations, correlated with good clinical response. Class-switched MemB were found accumulated in flaring joints. Conclusions The present data support the hypothesis that control of adaptive immune processes involving germinal centre-derived, antigen, and T-cell-dependently matured B cells is essential for successful RTX treatment.

Targeting autophagy as a potential therapeutic approach for melanoma therapy

Melanoma, occurring as a rapidly progressive skin cancer, is resistant to current chemo- and radiotherapy, especially after metastases to distant organs has taken place. Most chemotherapeutic drugs exert their cytotoxic effect by inducing apoptosis, which, however, is often deficient in cancer cells. Thus, it is appropriate to attempt the targeting of alternative pathways, which regulate cellular viability. Recent studies of autophagy, a well-conserved cellular catabolic process, promise to improve the therapeutic outcome in melanoma patients. Although a dual role for autophagy in cancer therapy has been reported, both protecting against and promoting cell death, the potential for using autophagy in cancer therapy seems to be promising. Here, we review the recent literature on the role of autophagy in melanoma with respect to the expression of autophagic markers, the involvement of autophagy in chemo- and immunotherapy, as well as the role of autophagy in hypoxia and altered metabolic pathways employed for melanoma therapy.

A papain-induced disc degeneration model for the assessment of thermo-reversible hydrogel-cells therapeutic approach

Nucleus pulposus (NP) regeneration by the application of injectable cell-embedded hydrogels is an appealing approach for tissue engineering. We investigated a thermo-reversible hydrogel (TR-HG), based on a modified polysaccharide with a thermo-reversible polyamide [poly(N-isopropylacrylamide), pNIPAM], which is made to behave as a liquid at room temperature and hardens at > 32 °C. In order to test the hydrogel, a papain-induced bovine caudal disc degeneration model (PDDM), creating a cavity in the NP, was employed. Human mesenchymal stem cells (hMSCs) or autologous bovine NP cells (bNPCs) were seeded in TR-HG; hMSCs were additionally preconditioned with rhGDF-5 for 7 days. Then, TR-HG was reversed to a fluid and the cell suspension injected into the PDDM and kept under static loading for 7 days. Experimental design was: (D1) fresh disc control + PBS injection; (D2) PDDM + PBS injection; (D3) PDDM + TR-HG (material control); (D4) PDDM + TR-HG + bNPCs; (D5) PDDM + TR-HG + hMSCs. Magnetic resonance imaging performed before and after loading, on days 9 and 16, allowed imaging of the hydrogel-filled PDDM and assessment of disc height and volume changes. In gel-injected discs the NP region showed a major drop in volume and disc height during culture under static load. The RT–PCR results of injected hMSCs showed significant upregulation of ACAN, COL2A1, VCAN and SOX9 during culture in the disc cavity, whereas the gene expression profile of NP cells remained unchanged. The cell viability of injected cells (NPCs or hMSCs) was maintained at over 86% in 3D culture and dropped to ~72% after organ culture. Our results underline the need for load-bearing hydrogels that are also cyto-compatible.

An MEKC assay for the therapeutic drug monitoring of cefepime

The development of a robust assay based on MEKC for cefepime in human serum and plasma with internal quality assurance is reported. Sample preparation comprises protein precipitation in the presence of SDS at pH 4.5. This is a gentle approach for which decomposition of cefepime during sample handling is negligible. After hydrodynamic sample injection of the supernatant, analysis occurs in a phosphate/borate buffer at pH 9.1 with 75 mM SDS using normal polarity and analyte detection at 257 nm. The MEKC run time interval and throughput are about 5 min and seven samples per hour, respectively. The calibration range for cefepime is 1-60 μg/mL, with 1 μg/mL being the LOQ. The performance of the assay with multilevel internal calibration was assessed with calibration and control samples. The assay is shown to be simple, inexpensive, reproducible, and robust. It was applied to determine cefepime levels in the sera of critically ill patients and to assess the instability of cefepime in patient and control samples. Our data revealed that serum containing cefepime can be stored at -20°C for a short time, whereas for long-term storage, samples have to be kept at -70°C.

Multiplex Liquid Chromatography-Tandem Mass Spectrometry Assay for Simultaneous Therapeutic Drug Monitoring of Ribavirin, Boceprevir, and Telaprevir

New directly acting antivirals (DAAs) that inhibit hepatitis C virus (HCV) replication are increasingly used for the treatment of chronic hepatitis C. A marked pharmacokinetic variability and a high potential for drug-drug interactions between DAAs and numerous drug classes have been identified. In addition, ribavirin (RBV), commonly associated with hemolytic anemia, often requires dose adjustment, advocating for therapeutic drug monitoring (TDM) in patients under combined antiviral therapy. However, an assay for the simultaneous analysis of RBV and DAAs constitutes an analytical challenge because of the large differences in polarity among these drugs, ranging from hydrophilic (RBV) to highly lipophilic (telaprevir [TVR]). Moreover, TVR is characterized by erratic behavior on standard octadecyl-based reversed-phase column chromatography and must be separated from VRT-127394, its inactive C-21 epimer metabolite. We have developed a convenient assay employing simple plasma protein precipitation, followed by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) for the simultaneous determination of levels of RBV, boceprevir, and TVR, as well as its metabolite VRT-127394, in plasma. This new, simple, rapid, and robust HPLC-MS/MS assay offers an efficient method of real-time TDM aimed at maximizing efficacy while minimizing the toxicity of antiviral therapy.

Bullous pemphigoid: therapeutic algrorithm and practical management

Introduction: Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease of the skin and mucosae. BP typically affects the elderly and manifests with severe itch, localised or generalised eczematous, urticated and/or bullous lesions. Its morbidity and impact on the quality of life are important. The disease is significantly associated with neurological disorders, such as stroke, Parkinson disease, major cognitive impairment and multiple sclerosis. Diagnosis of BP critically relies on immunopathologic examinations, particularly direct immunofluorescence microscopy studies. Areas covered: This paper looks at the evidence of therapies commonly used in bullous pemphigoid. Expert opinion: Treatment of BP has been a challenge, given the relative rarity of the disease, lack of good quality randomised controlled trials, the presence of co-morbidities in the affected elderly population and the high mortality rate. Recent controlled studies have indicated that potent topical corticosteroids constitute a more effective therapy for BP when compared to oral corticosteroids in terms of control of the disease, side effect profile and overall survival. Other therapies have been employed with varying success, but are not validated yet. Improved knowledge of the pathophysiology of BP will hopefully allow the development of new immunomodulatory treatments for this debilitating disease.

Sonic intelligence as a virtual therapeutic environment

This paper reports on the results of a research project, on comparing one virtual collaborative environment with a first-person visual immersion (first-perspective interaction) and a second one where the user interacts through a sound-kinetic virtual representation of himself (avatar), as a stress-coping environment in real-life situations. Recent developments in coping research are proposing a shift from a trait-oriented approach of coping to a more situation-specific treatment. We defined as real-life situation a target-oriented situation that demands a complex coping skills inventory of high self-efficacy and internal or external "locus of control" strategies. The participants were 90 normal adults with healthy or impaired coping skills, 25-40 years of age, randomly spread across two groups. There was the same number of participants across groups and gender balance within groups. All two groups went through two phases. In Phase I, Solo, one participant was assessed using a three-stage assessment inspired by the transactional stress theory of Lazarus and the stress inoculation theory of Meichenbaum. In Phase I, each participant was given a coping skills measurement within the time course of various hypothetical stressful encounters performed in two different conditions and a control group. In Condition A, the participant was given a virtual stress assessment scenario relative to a first-person perspective (VRFP). In Condition B, the participant was given a virtual stress assessment scenario relative to a behaviorally realistic motion controlled avatar with sonic feedback (VRSA). In Condition C, the No Treatment Condition (NTC), the participant received just an interview. In Phase II, all three groups were mixed and exercised the same tasks but with two participants in pairs. The results showed that the VRSA group performed notably better in terms of cognitive appraisals, emotions and attributions than the other two groups in Phase I (VRSA, 92%; VRFP, 85%; NTC, 34%). In Phase II, the difference again favored the VRSA group against the other two. These results indicate that a virtual collaborative environment seems to be a consistent coping environment, tapping two classes of stress: (a) aversive or ambiguous situations, and (b) loss or failure situations in relation to the stress inoculation theory. In terms of coping behaviors, a distinction is made between self-directed and environment-directed strategies. A great advantage of the virtual collaborative environment with the behaviorally enhanced sound-kinetic avatar is the consideration of team coping intentions in different stages. Even if the aim is to tap transactional processes in real-life situations, it might be better to conduct research using a sound-kinetic avatar based collaborative environment than a virtual first-person perspective scenario alone. The VE consisted of two dual-processor PC systems, a video splitter, a digital camera and two stereoscopic CRT displays. The system was programmed in C++ and VRScape Immersive Cluster from VRCO, which created an artificial environment that encodes the user's motion from a video camera, targeted at the face of the users and physiological sensors attached to the body.

Life-threatening adverse events following therapeutic opioid administration in adults: Is pharmacogenetic analysis useful?

BACKGROUND Systemic approaches are needed to understand how variations in the genes associated with opioid pharmacokinetics and response can be used to predict patient outcome. The application of pharmacogenetic analysis to two cases of life-threatening opioid-induced respiratory depression is presented. The usefulness of genotyping in the context of these cases is discussed. METHODS A panel of 20 functional candidate polymorphisms in genes involved in the opioid biotransformation pathway (CYP2D6, UGT2B7, ABCB1, OPRM1, COMT) were genotyped in these two patients using commercially available genotyping assays. RESULTS In case 1, the patient experienced adverse outcomes when administered codeine and morphine, but not hydromorphone. Genetic test results suggested that this differential response may be due to an inherent propensity to generate active metabolites from both codeine and morphine. These active metabolites are not generated with hydromorphone. In case 2, the patient experienced severe respiratory depression during postoperative recovery following standard doses of morphine. The patient was found to carry genetic variations that result in decreased morphine efflux transporter activity at the blood-brain barrier and increased sensitivity to opioids. CONCLUSIONS Knowledge of the relative contribution of pharmacogenetic biomarkers and their influence on opioid response are continually evolving. Pharmacogenetic analysis, together with clinical history, has the potential to provide mechanistic insight into severe respiratory depressive events in patients who receive opioids at therapeutic doses.

Introduction of two novel devices for investigating the influence of non-mechanical components such as therapeutic qi in acupuncture

OBJECTIVE: Acupuncture is a complex intervention consisting of specific and non-specific components. Acupuncture studies more frequently focus on collecting data from the patients’ perspective and response, but the acupuncturist’s role remains relatively unclear. In order to investigate potential non-mechanical active factors originating from the acupuncturist and transmitted to the patient during treatment, two novel devices for basic research in acupuncture were designed. The Acuplicator allows the researcher to insert needles without touching the needles themselves, while the Veliusator locks the needle in its place so that no mechanical movement can be transferred. METHODS: The Acuplicator was used to insert needles at Neiguan (PC6) on the right forearm of 23 volunteers. The insertion depth was measured using a depth gauge. The transfer of mechanical movements from the handle to the tip was detected with a precision length gauge with a motoric-tactile sensor. RESULTS: The mean insertion depth was (12.3 ± 1.5) mm (range 9.5 to 15.0 mm). Even with intense manipulation of the needle handle, no movements within ± 1 μm could be detected at the tip when the needle was locked. CONCLUSION: With these two devices it will be possible to investigate the influence of non-mechanical components such as therapeutic qi in acupuncture.