Polyanalgesic Consensus Conference-2012: Recommendations to Reduce Morbidity and Mortality in Intrathecal Drug Delivery in the Treatment of Chronic Pain.

Introduction:  Targeted intrathecal drug infusion to treat moderate to severe chronic pain has become a standard part of treatment algorithms when more conservative options fail. This therapy is well established in the literature, has shown efficacy, and is an important tool for the treatment of both cancer and noncancer pain; however, it has become clear in recent years that intrathecal drug delivery is associated with risks for serious morbidity and mortality. Methods:  The Polyanalgesic Consensus Conference is a meeting of experienced implanting physicians who strive to improve care in those receiving implantable devices. Employing data generated through an extensive literature search combined with clinical experience, this work group formulated recommendations regarding awareness, education, and mitigation of the morbidity and mortality associated with intrathecal therapy to establish best practices for targeted intrathecal drug delivery systems. Results:  Best practices for improved patient care and outcomes with targeted intrathecal infusion are recommended to minimize the risk of morbidity and mortality. Areas of focus include respiratory depression, infection, granuloma, device-related complications, endocrinopathies, and human error. Specific guidance is given with each of these issues and the general use of the therapy. Conclusions:  Targeted intrathecal drug delivery systems are associated with risks for morbidity and mortality that can be devastating. The panel has given guidance to treating physicians and healthcare providers to reduce the incidence of these problems and to improve outcomes when problems occur.

Use of combined suspension laryngoscopy and jet ventilation for Y-shaped airway stents delivery.

Airway stenting is a common endoscopic procedure that is used to treat a variety of central airway lesions. Obstructions or fistulas involving the carina or nearby tracheobronchial structures require the use of specially designed stents, commonly referred to as Y-stents. Conventional methods of endobronchial Y-stent delivery are all characterized by a blind and apneic period during the procedure that carries the risk of stent misplacement or ventilation/oxygenation problems or both. Using combined suspension laryngoscopy, flexible bronchoscopy, and jet ventilation, we describe a technique that makes challenging bronchoscopic interventions--such as self-expandable Y-shaped airway stent delivery--easy, precise, and safe.

Enhanced oligonucleotide delivery to mouse retinal cells using iontophoresis.

PURPOSE: To study the combination of oligodeoxynucleotides (ODNs) intravitreous injection and saline transpalpebral iontophoresis on the delivery of ODNs to photoreceptors in the newborn rd1/rd1 mice. METHODS: Cathodal or anodal transpalpebral iontophoresis (1.43 mA/cm(2) for 5 min) was applied to eyes of postnatal day 7 (PN7) rd1/rd1 mice immediately before the intravitreous injection of ODNs. The effect of cathodal iontophoresis after ODNs injection was also evaluated. The influence of current intensity (0.5, 1.5, and 2.5 mA) was assayed with cathodal iontophoresis performed prior to ODNs injection. The duration of current-induced facilitation of ODNs delivery to photoreceptors was evaluated for 6 h following iontophoresis. One group of control eyes received cathodal iontophoresis prior to the intravitreous injection of phosphate buffered saline (PBS) or hexachlorofluorescein (Hex). The second control group received ODN or Hex intravitreous injection without iontophoresis. The penetration of fluorescent ODNs in the outer nuclear layer (ONL) was quantified by image analysis of the ONL fluorescence intensity on cryosection microphotographs. Integrity of ODN was assessed using acrylamide gel migration after its extraction from the retina of treated mice. The integrity of retinal structure, 1 and 24 h after iontophoresis, was analyzed using light and electron microscopy. RESULTS: Transpalpebral anodal or cathodal saline iontophoresis enhanced the penetration of ODNs in all retinal layers. Cathodal iontophoresis was more efficient than anodal iontophoresis in enhancing the tissue penetration of the injected ODN. Photoreceptor delivery of ODN was significantly higher when cathodal saline transpalpebral iontophoresis was applied prior than after the injection. The extent of enhanced tissue penetration decreased in parallel to the increased interval between iontophoresis application and the intravitreous injection. Current of 1.5 mA was safe and optimal for the delivery of ODNs to the ONL. One hour after iontophoresis followed by injection, ODN extracted from the retina of treated eyes remained intact. Histology and electron microscopy observations demonstrated that iontophoresis using the optimal parameters did not induce any permanent tissue alterations or structure damage. CONCLUSIONS: Saline transpalpebral iontophoresis facilitates the penetration of injected ODNs in photoreceptors for at least 3 h. This method may be considered for photoreceptor targeted gene therapy.

Routine delivery of artemisinin-based combination treatment at fixed health facilities reduces malaria prevalence in Tanzania: an observational study.

BACKGROUND: Artemisinin-based combination therapy (ACT) has been promoted as a means to reduce malaria transmission due to their ability to kill both asexual blood stages of malaria parasites, which sustain infections over long periods and the immature derived sexual stages responsible for infecting mosquitoes and onward transmission. Early studies reported a temporal association between ACT introduction and reduced malaria transmission in a number of ecological settings. However, these reports have come from areas with low to moderate malaria transmission, been confounded by the presence of other interventions or environmental changes that may have reduced malaria transmission, and have not included a comparison group without ACT. This report presents results from the first large-scale observational study to assess the impact of case management with ACT on population-level measures of malaria endemicity in an area with intense transmission where the benefits of effective infection clearance might be compromised by frequent and repeated re-infection. METHODS: A pre-post observational study with a non-randomized comparison group was conducted at two sites in Tanzania. Both sites used sulphadoxine-pyrimethamine (SP) monotherapy as a first-line anti-malarial from mid-2001 through 2002. In 2003, the ACT, artesunate (AS) co-administered with SP (AS + SP), was introduced in all fixed health facilities in the intervention site, including both public and registered non-governmental facilities. Population-level prevalence of Plasmodium falciparum asexual parasitaemia and gametocytaemia were assessed using light microscopy from samples collected during representative household surveys in 2001, 2002, 2004, 2005 and 2006. FINDINGS: Among 37,309 observations included in the analysis, annual asexual parasitaemia prevalence in persons of all ages ranged from 11% to 28% and gametocytaemia prevalence ranged from <1% to 2% between the two sites and across the five survey years. A multivariable logistic regression model was fitted to adjust for age, socioeconomic status, bed net use and rainfall. In the presence of consistently high coverage and efficacy of SP monotherapy and AS + SP in the comparison and intervention areas, the introduction of ACT in the intervention site was associated with a modest reduction in the adjusted asexual parasitaemia prevalence of 5 percentage-points or 23% (p < 0.0001) relative to the comparison site. Gametocytaemia prevalence did not differ significantly (p = 0.30). INTERPRETATION: The introduction of ACT at fixed health facilities only modestly reduced asexual parasitaemia prevalence. ACT is effective for treatment of uncomplicated malaria and should have substantial public health impact on morbidity and mortality, but is unlikely to reduce malaria transmission substantially in much of sub-Saharan Africa where individuals are rapidly re-infected.

Intrathecal drug delivery systems for cancer pain

Introduction: A substantial number of patients with cancer suffer considerable pain at some point during their disease, and approximately 25% of cancer patients die in pain. In cases of uncontrolled pain or intolerable side effects, intrathecal drug delivery system (IDDS) is a recognised management option. Indeed, IDDS offer rapid and effective pain relief with less drug side effects compared to oral or parenteral administration. The aim of this study is to retrospectively review our series of cancer patients treated with IDDS. Method: Data was extracted from the institutional neuromodulation registry. Patients with cancer pain treated with IDDS from 01.01.1997 to 30.12.2009 were analysed for subjective improvement, changes in pain intensity (VAS) and survival time after implantation. Measurements were available for a decreasing number of patients as time since baseline increased. Results: During the studied period, 78 patients were implanted with IDDS for cancer pain. The mean survival time was 11.1 months (median: 3.8 months) and 14 patients (18%) were still alive at the end of the studied period. Subjective improvement was graded between 55 and 83% during the first year. Mean VAS during the first year remained lower than VAS at baseline. Discussion: IDDS has been shown to be cost-effective in several studies. Although initial costs of implantation are high, the cost benefits favour analgesia with implanted intrathecal pumps over epidural external systems after 3 to 6 months in cancer patients. Improved survival has been associated with IDDS and in this series both the mean and median survival times were above the cut-off value of three months. The mean subjective improvement was above 50% during the whole first year, suggesting a good efficacy of the treatment, a finding that is consistent with the results from other groups. Changes in pain intensity are difficult to interpret in the context of rapidly progressive disease such as in terminal cancer. However, mean VAS from 1 thru12 months were lower than baseline, suggesting improved pain control with IDDS, or at least a stabilisation of the pain symptoms. Conclusion: Our retrospective series suggests IDDS is effective in intractable cancer pain and we believe it should be considered even in terminally ill patients with limited life expectancies.

Reduced choroidal neovascularization by AAV-anti-VEGF shRNA delivery

VEGF plays an essential role in ocular angiogenic diseases including the late-stage form of AMD, the primary cause of vision loss in the western world. Over-expression of VEGF leads to development of vasculature emanating from the choroid, invading the subretinal space through breaks in Bruch's membrane. Strategies leading to long-term suppression of inappropriate ocular angiogenesis are required. A panel of 10 shRNAs targeting the coding region of human VEGF165 was tested in HEK293 cells and in the human retinal pigment epithelial cell line, ARPE-19. VEGF knock-down up to 92% was achieved by co-transfecting shRNAexpressing constructs with plasmid encoding the Renilla luciferase gene fused to the VEGF165 sequence. For in vivo delivery of the most potent shRNA cassette, both single-stranded and self-complementary rAAV vectors were packaged in serotype 8 capsids. Intramuscular administration in mice led to localized expression and 96% knock-down of endogenous VEGF. Using eGFP as a marker, efficient gene transfer of retinal pigment epithelial cells, the cells thought to be responsible for the abnormal VEGF production, was obtained by subretinal delivery of rAAV2.8 vectors. The capacity of rAAV-encoded shRNAs to silence endogenous VEGF gene expression was evaluated in the laser-induced murine model of choroidal neovascularization (CNV). In this mouse model of AMD, sizes of the CNV were found to be significantly reduced following rAAV-shRNA subretinal delivery. Thus, our results indicate that gene transfer combining AAV-mediated delivery with triggering of the endogenous RNAi pathway can be used for anti-VEGF therapy and holds great promise for the treatment of AMD.

Evaluating in vivo delivery of riboflavin with coulomb-controlled iontophoresis for corneal collagen cross-linking: a pilot study.

PURPOSE: To evaluate the efficacy of coulomb-controlled iontophoresis (CCI) for delivery of riboflavin prior to corneal collagen cross-linking (CXL). METHODS: The eyes of 20 8-week-old Lewis rats, subject to epithelium-ON (epi-ON, n = 20 eyes) or epithelium-OFF (epi-OFF, n = 20 eyes) conditions, were used to evaluate the in vivo delivery of two riboflavin solutions: 0.1% riboflavin-20% dextran T500 solution (riboflavin-dextran) and 0.1% riboflavin 5'-phosphate (riboflavin-phosphate). After systemic intramuscular anesthesia, 0.25 mL of the photosensitizing agent was delivered by either instillation or CCI (2.11 mA/cm(2) for 4 or 10 minutes) into either epithelial condition. The CCI probe on the eye without current served as control. Confocal microscopy of flat-mounted corneas was used to analyze intracorneal penetration and fluorometry was used to quantify riboflavin in the aqueous within 30 minutes of treatment. RESULTS: Instillation and CCI allowed for uniform delivery of riboflavin-dextran throughout the stroma after epithelial debridement. Transepithelial delivery of riboflavin-dextran was not efficacious. Riboflavin-phosphate was successfully delivered in both epithelium conditions. Complete saturation of the cornea was achieved using CCI after removing the epithelium, the epi-ON case allowed for limited diffusion. Increasing the time from 4 to 10 minutes greatly increased the amount of riboflavin detected in the cornea and aqueous humor. CONCLUSIONS: Coulomb-controlled iontophoresis is an effective technique for transepithelial delivery of riboflavin-phosphate into the cornea. This drug delivery method would allow clinicians to significantly shorten the time required for the CXL procedure, with or without epithelial debridement. Whether efficient crosslinking can be achieved through an intact epithelium remains to be demonstrated.

Development of a dose-controlled multiculture cell exposure chamber for efficient delivery of airborne and engineered nanoparticles

In order to study the various health influencing parameters related to engineered nanoparticles as well as to soot emitted b diesel engines, there is an urgent need for appropriate sampling devices and methods for cell exposure studies that simulate the respiratory system and facilitate associated biological and toxicological tests. The objective of the present work was the further advancement of a Multiculture Exposure Chamber (MEC) into a dose-controlled system for efficient delivery of nanoparticles to cells. It was validated with various types of nanoparticles (diesel engine soot aggregates, engineered nanoparticles for various applications) and with state-of-the-art nanoparticle measurement instrumentation to assess the local deposition of nanoparticles on the cell cultures. The dose of nanoparticles to which cell cultures are being exposed was evaluated in the normal operation of the in vitro cell culture exposure chamber based on measurements of the size specific nanoparticle collection efficiency of a cell free device. The average efficiency in delivering nanoparticles in the MEC was approximately 82%. The nanoparticle deposition was demonstrated by Transmission Electron Microscopy (TEM). Analysis and design of the MEC employs Computational Fluid Dynamics (CFD) and true to geometry representations of nanoparticles with the aim to assess the uniformity of nanoparticle deposition among the culture wells. Final testing of the dose-controlled cell exposure system was performed by exposing A549 lung cell cultures to fluorescently labeled nanoparticles. Delivery of aerosolized nanoparticles was demonstrated by visualization of the nanoparticle fluorescence in the cell cultures following exposure. Also monitored was the potential of the aerosolized nanoparticles to generate reactive oxygen species (ROS) (e.g. free radicals and peroxides generation), thus expressing the oxidative stress of the cells which can cause extensive cellular damage or damage on DNA.

Prospective randomized study of two cryopreservation policies avoiding embryo selection: the pronucleate stage leads to a higher cumulative delivery rate than the early cleavage stage.

OBJECTIVE: To compare the cumulative live birth rates obtained after cryopreservation of either pronucleate (PN) zygotes or early-cleavage (EC) embryos. DESIGN: Prospective randomized study. SETTING: University hospital. PATIENT(S): Three hundred eighty-two patients, involved in an IVF/ICSI program from January 1993 to December 1995, who had their supernumerary embryos cryopreserved either at the PN (group I) or EC (group II) stage. For 89 patients, cryopreservation of EC embryos was canceled because of poor embryo development (group III). Frozen-thawed embryo transfers performed up to December 1998 were considered. MAIN OUTCOME MEASURE(S): Age, oocytes, zygotes, cryopreserved and transferred embryos, damage after thawing, cumulative embryo scores, implantation, and cumulative live birth rates. RESULT(S): The clinical pregnancy and live birth rates were similar in all groups after fresh embryo transfers. Significantly higher implantation (10.5% vs. 5.9%) and pregnancy rates (19.5% vs. 10.9%; P< or = .02 per transfer after cryopreserved embryo transfers were obtained in group I versus group II, leading to higher cumulative pregnancy (55.5% vs. 38.6%; P < or = .002 and live birth rates (46.9% vs. 27.7%; P< or = .0001.Conclusion(s): The transfer of a maximum of three unselected embryos and freezing of all supernumerary PN zygotes can be safely done with significantly higher cumulative pregnancy chances than cryopreserving at a later EC stage.

Local Public-Services Provision under Public-Private Partnerships : Contractual Design and Contracting Parties Incentives

When deciding to resort to a PPP contract for the provision of a local public service, local governments have to consider the demand risk allocation between the contracting parties. In this article, I investigate the effects of demand risk allocation on the accountability of procuring authorities regarding consumers changing demand, as well as on the cost-reducing effort incentives of the private public-service provider. I show that contracts in which the private provider bears demand risk motivate more the public authority from responding to customer needs. This is due to the fact that consumers are empowered when the private provider bears demand risk, that is, they have the possibility to oust the private provider in case of non-satisfaction with the service provision, which provides procuring authorities with more credibility in side-trading and then more incentives to be responsive. As a consequence, I show that there is a lower matching with consumers' preferences over time when demand risk is on the public authority rather than on the private provider, and this is corroborated in the light of two famous case studies. However, contracts in which the private provider does not bear demand risk motivate more the private provider from investing in cost-reducing efforts. I highlight then a tradeoff in the allocation of demand risk between productive and allocative efficiency. The striking policy implication of this article for local governments would be that the current trend towards a greater resort to contracts where private providers bear little or no demand risk may not be optimal. Local governments should impose demand risk on private providers within PPP contracts when they expect that consumers' preferences over the service provision will change over time.

Release of vancomycin and teicoplanin from a plasticized and resorbable gelatin sponge: in vitro investigation of a new antibiotic delivery system with glycopeptides.

BACKGROUND: The aim of this study was to evaluate the efficacy of sustained release of vancomycin and teicoplanin from a resorbable gelatin glycerol sponge, in order to establish a new delivery system for local anti-infective therapy. MATERIALS AND METHODS: 60 plasticized glycerol gelatin sponges containing either 10 or 20% gelatin (w/v) were incubated in vancomycin or teicoplanin solution at 20 degrees C for either 1 or 24 h. In vitro release properties of the sponges were investigated over a period of 1 week by determining the levels of vancomycin and teicoplanin eluted in plasma using fluorescent polarization immunoassay. The rate constant and the half-life for the antibiotic release of each group were calculated by linear regression assuming first order kinetics. RESULTS: Presoaking for 24 h was associated with a significant increase in the total antibiotic release in all groups opposed to 1 h of incubation, except for the 10% sponges presoaked in teicoplanin. Doubling the gelatin content of the sponges from 10 to 20% significantly increased the total release of antibiotic load only in teicoplanin-containing sponges after 24 h incubation. In all corresponding groups investigated, release of vancomycin was more prolonged compared to teicoplanin, which allowed a gradual release beyond 5 days. The half-life (h +/- SEM) of both types of vancomycin-containing sponges was significantly prolonged by 24 h incubation in comparison to 1 h incubation (29.1 +/- 5.9 vs 5.9 +/- 1.0; p < 0.001, 30.0 +/- 2.1 vs 11.1 +/- 1.9; p < 0.001). However, neither doubling the gelatin content of the sponges nor a prolonged incubation was associated with a significantly prolonged delivery of teicoplanin. CONCLUSION: This study demonstrated a better diffusion-controlled release of vancomycin-impregnated glycerol gelatin sponges compared to those pretreated with teicoplanin. The plasticized glycerol gelatin sponge may be a promising carrier for the application of vancomycin to infected wounds for local anti-infective therapy.

Controlled delivery of 5-chlorouracil using poly(ortho esters) in filtering surgery for glaucoma.

PURPOSE: To evaluate the antimitotic and toxic effects of 5-chlorouracil (5-CU) and 5-fluorouracil (5-FU) and study their potential to delay filtering bleb closure in the rabbit eye when released by poly(ortho esters) (POE). METHODS: Rabbit Tenon fibroblasts and human conjunctival cells were incubated with various 5-CU and 5-FU concentrations. Antiproliferative effects and toxicity were evaluated at 24 and 72 hours by monotetrazolium, neutral red, and Hoechst tests and cell counting. Mechanisms of cell death were evaluated using TUNEL assay, annexin V binding, immunohistochemistry for anti-apoptosis-inducing factor (AIF) and LEI/L-DNase II. Trabeculectomy was performed in pigmented rabbits. Two hundred microliters of POE loaded with 1% wt/wt 5-FU or 5-CU was injected into the subconjunctival space after surgery. Intraocular pressure (IOP) and bleb persistence were monitored for 150 days. RESULTS: In vitro, 5-FU showed a higher antiproliferative effect and a more toxic effect than 5-CU. 5-FU induced cell necrosis, whereas 5-CU induced mostly apoptosis. The apoptosis induced by 5-CU was driven through a non-caspase-dependent pathway involving AIF and LEI/L-DNase II. In vivo, at 34 days after surgery, the mean IOP in the POE/5-CU-treated group was 83% of the baseline level and only 40% in the POE/5-FU-treated group. At 100 days after surgery, IOP was still decreased in the POE/5-CU group when compared with the controls and still inferior to the preoperative value. The mean long-term IOP, with all time points considered, was significantly (P < 0.0001) decreased in the POE/5-CU-treated group (6.0 +/- 2.4 mm Hg) when compared with both control groups, the trabeculectomy alone group (7.6 +/- 2.9 mm Hg), and the POE alone group (7.5 +/- 2.6 mm Hg). Histologic analysis showed evidence of functioning blebs in the POE-5-CU-treated eyes along with a preserved structure of the conjunctiva epithelium. CONCLUSIONS: The slow release of 5-CU from POE has a longstanding effect on the decrease of IOP after glaucoma-filtering surgery in the rabbit eye. Thus, the slow release of POE/5-CU may be beneficial for the prevention of bleb closure in patients who undergo complicated trabeculectomy.

Dispositifs de délivrance de principes actifs pour des applications ophtalmologiques [Drug delivery systems for intraocular applications].

Numerous drug delivery systems (DDSs) can be used as intraocular tools to provide a sustained and calibrated release for a specific drug. Great progress has been made on the design, biocompatibility, bioavailability, and efficacy of DDSs. Although several of them are undergoing clinical trials, a few are already on the market and could be of a routine use in clinical practice. Moreover, miniaturization of the implants makes them less and less traumatic for the eye tissues and some DDSs are now able to target certain cells or tissues specifically. An overview of ocular implants with therapeutic application potentials is provided.

Cellular delivery of pyrenyl-arene ruthenium complexes by a water-soluble arene ruthenium metalla-cage.

Three pyrenyl-arene ruthenium complexes (M(1)-M(3)) of the general formula [Ru(η(6)-arene-pyrenyl)Cl(2)(pta)] (pta = 1,3,5-triaza-7-phosphaadamantane) have been synthesised and characterised. Prior to the coordination to ruthenium, pyrene was connected to the arene ligand via an alkane chain containing different functional groups: ester (L(1)), ether (L(2)) and amide (L(3)), respectively. Furthermore, the pyrenyl moieties of the M(n) complexes were encapsulated within the hydrophobic cavity of the water soluble metalla-cage, [Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+) (tpt = 2,4,6-tri-(pyridin-4-yl)-1,3,5-triazine; donq = 5,8-dioxydo-1,4-naphthoquinonato), while the arene ruthenium end was pointing out of the cage, thus giving rise to the corresponding host-guest systems [M(n)⊂Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+) ([M(n)⊂cage](6+)). The antitumor activity of the pyrenyl-arene ruthenium complexes (M(n)) and the corresponding host-guest systems [M(n)⊂cage][CF(3)SO(3)](6) were evaluated in vitro in different types of human cancer cell lines (A549, A2780, A2780cisR, Me300 and HeLa). Complex M(2), which contains an ether group within the alkane chain, demonstrated at least a 10 times higher cytotoxicity than the reference compound [Ru(η(6)-p-cymene)Cl(2)(pta)] (RAPTA-C). All host-guest systems [M(n)⊂cage](6+) showed good anticancer activity with IC(50) values ranging from 2 to 8 μM after 72 h exposure. The fluorescence of the pyrenyl moiety allowed the monitoring of the cellular uptake and revealed an increase of uptake by a factor two of the M(2) complex when encapsulated in the metalla-cage [Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+).

Severe hypertension following accidental clonidine overdose during the refilling of an implanted intrathecal drug delivery system.

BACKGROUND:   Complications associated with intrathecal pumps may be linked to the surgical procedure, the implanted device, or the medication itself.¦CASE REPORTS:   Three patients treated chronically with intrathecal clonidine presented with clonidine overdose due to inadvertent extravasation during the refilling procedure. All patients experienced loss of consciousness and severe systemic hypertension that required aggressive parenteral treatment.¦DISCUSSION:   Clonidine is an alpha-2 agonist with a nearly 100% bioavailability after oral or rectal administration. With high plasma concentration secondary to massive systemic overdose, the specificity for the alpha-2 receptor is lost and an alpha-1 agonist activity predominates and causes marked hypertension. Management of clonidine overdose consists of supportive therapy guided by signs and symptoms.¦CONCLUSION:   Inadvertent injection into the subcutaneous pocket rather than the reservoir is rare but very dangerous as the drug cannot be retrieved and massive doses are involved. Signs and symptoms of systemic overdose with drugs commonly used in implanted drugs delivery system should be well known to ensure early diagnosis and treatment.