Injections

Treatment of mice with hydroxyurea to selectively kill all cycling cells has been used to study population dynamics and life expectancy of “natural” immunoglobulin-secreting cells in the bone marrow and spleen of nonimmunized animals. The results show that 50 to 90% of those cells are eliminated 2 to 3 days after one cycle of hydroxyurea administration, demonstrating their recent origin from cycling precursors. Using a protocol of long-term hydroxyurea treatment which abrogates cell production from the cycling precursors compartments, it was shown that “natural” immunoglobulin-secreting cells have a very short half renewal time, in the range of 15–60 h.

Needles with asymmetric bevel tips naturally bend when they are inserted into soft tissue. In this study, we present an analytical model for the loads developed at the bevel tip during needle-tissue interaction. The model calculates the loads based on the geometry of the bevel edge and gel material properties. The modeled transverse force developed at the tip is compared to forces measured experimentally. The analytical model explains the trends observed in the experiments. In addition to macroscopic studies, we also present microscopic observations of needle-tissue interactions. These results contribute to a mechanics-based model of robotic needle steering, extending previous work on kinematic models.

Common complications of intracavernous injection therapy include pain, hematoma formation, syncope, prolonged erections, and penile fibrosis. Rare reported complications include postinjection cavernositis, intracorporeal needle breakage. We report a case of postinjection intracavernous needle breakage with successful ultrasound-guided retrieval. A 32-year-old patient complaining of a 6-month penile pain following intracavernous papaverine injection presented to our department. Clinical examination and penile ultrasound revealed a broken intracavernous needle at the left mid-dorsum aspect of the penis with surrounding fibrosis. A decision was made to remove the broken needle. The needle was dislodged effortlessly under local anesthesia. A deeply seated intracavernous broken needle should be immediately retrieved. Patients must be carefully instructed on the proper injection technique with emphasis on the delicacy of the needle and the possibility of needle breakage during injection.

In this paper, we present design of a transdermal drug delivery system for treatment of cardiovascular or hemodynamic disorders such as hypertension. The system comprises of integrated control electronics and microelectromechanical system devices such as micropump, micro blood pressure sensor and microneedle array. The objective is to overcome the limitations of oral therapy such as variable absorption profile and the need for frequent dosing, by fabricating a safe, reliable and cost effective transdermal drug delivery system to dispense various pharmacological agents through the skin for treatment of hemodynamic dysfunction such as hypertension. Moreover, design optimization of a piezoelectrically actuated valveless micropump is presented for the drug delivery system. Because of the complexity in analysis of piezoelectric micropump, which involves structural and fluid field couplings in a complicated geometrical arrangement, finite element (FE) numerical simulation rather than an analytical system has been used. The behavior of the piezoelectric actuator with biocompatible polydimethylsiloxane membrane is first studied by conducting piezoelectric analysis. Then the performance of the valveless micropump is analyzed by building a three dimensional electric-solid-fluid model of the micropump. The effect of geometrical dimensions on micropump characteristics and efficiency of nozzle/diffuser elements of a valveless micropump is investigated in the transient analysis using multiple code coupling method. The deformation results of the membrane using multifield code coupling analysis are in good agreement with analytical as well as results of single code coupling analysis of a piezoelectric micropump. The analysis predicts that to enhance the performance of the micropump, diffuser geometrical dimensions such as diffuser length, diffuser neck width and diffuser angle need to be optimized. Micropump flow rate is not strongly affected at low excitation frequencies from 10 to 200 Hz. The excitation voltage is the more dominant factor that affects the flow rate of the micropump as compared with the excitation frequency. However, at extremely high excitation frequencies beyond 8,000 Hz, the flow rate drops as the membrane exhibits multiple bending peaks which is not desirable for fluid flow. Following the extensive numerical analysis, actual fabrication and performance characterization of the micropump is presented. The performance of the micropump is characterized in terms of piezoelectric actuator deflection and micropump flow rate at different operational parameters. The set of multifield simulations and experimental measurement of deflection and flow rate at varying voltage and excitation frequency is a significant advance in the study of the electric-solid-fluid coupled field effects as it allows transient, three dimensional piezoelectric and fluid analysis of the micropump thereby facilitating a more realistic multifield analysis. The results of the present study will also help to conduct relevant strength duration tests of integrated drug delivery device with micropump and microneedle array in future.

Discontinuation of injectable disease-modifying therapy (DMT) for multiple sclerosis (MS) after a long period of relapse freedom is frequently considered, but data on post-cessation disease course are lacking. (1) To compare time to first relapse and disability progression among 'DMT stoppers' and propensity-score matched 'DMT stayers' in the MSBase Registry; (2) To identify predictors of time to first relapse and disability progression in DMT stoppers. Inclusion criteria for DMT stoppers were: age ≥18 years; no relapses for ≥5 years at DMT discontinuation; follow-up for ≥3 years after stopping DMT; not restarting DMT for ≥3 months after discontinuation. DMT stayers were required to have no relapses for ≥5 years at baseline, and were propensity-score matched to stoppers for age, sex, disability (Expanded Disability Status Score), disease duration and time on treatment. Relapse and disability progression events in matched stoppers and stayers were compared using a mar...

In this article, we investigate whether (1) the IINFVo (Impression, Intelligibility, Noise, Fluency and Voicing) perceptual rating scale and (2) the AMPEX (Auditory Model Based Pitch Extractor) acoustical analysis are suitable for evaluating adductor spasmodic dysphonia (AdSD). Voice recordings of 12 patients were analysed. The inter-rater and intra-rater consistency showed highly significant correlations for the IINFVo rating scale, with the exception of the parameter Noise. AMPEX reliably analyses vowels (correlation between PUVF (percentage of frames with unreliable F0/voicing 0.748), running speech (correlation between PVF (percentage of voiced frames)/voicing 0.699) and syllables. Correlations between IINFVo and AMPEX range from 0.608 to 0.818, except for noise. This study indicates that IINFVo and AMPEX could be robust and complementary assessment tools for the evaluation of AdSD. Both the tools provide us with the valuable information about voice quality, stability of F0 (fundamental frequency) and specific dimensions controlling the transitions between voiced and unvoiced segments.

Background:  The efficacy of injection therapy in diabetes depends on correct injection technique and, to provide patients with guidance in this area, we must understand how they currently inject.Methods:  From September 2008 to June 2009, 4352 insulin-injecting Type 1 and Type 2 diabetic patients from 171 centers in 16 countries were surveyed regarding their injection practices.Results:  Overall, 3.6% of patients use the 12.7-mm needle, 1.8% use the 12-mm needle, 1.6% use the 10-mm needle, 48.6% use the 8-mm needle, 15.8% use the 6-mm needle, and 21.6% use the 5-mm needle; 7% of patients do not know what length of needle they use. Twenty-one percent of patients admitted injecting into the same site for an entire day, or even a few days, a practice associated with lipohypertrophy. Approximately 50% of patients have or have had symptoms suggestive of lipohypertrophy. Abdominal lipohypertrophy seems to be more frequent in those using the two smaller injection size areas, and less frequent in those using larger areas. Nearly 3% of patients reported always injecting into lipohypertrophic lesions and 26% inject into them sometimes. Of the 65% of patients using cloudy insulins (e.g. NPH), 35% do not remix it before use.Conclusions:  It is clear from the latest survey that we have improved in certain areas, but that, in others, we have either not moved at all or our efforts have not yielded the results we expected. The results of the present survey are available online on a country-by-country and question-by-question basis at http://www.titan-workshop.org.

INTRODUCTION Andropause and aging are associated with neuroendocrine dysfunctions. Growth hormone and testosterone play a significant role in several processes affecting adaptation and thereby also everyday functioning. The aim of this research project was to evaluate the effects of recombinant human growth hormone and testosterone enanthate injections on body mass and body composition, aerobic and anaerobic fitness and lipid profile in middle-aged men. MATERIALS AND METHOD The research group was comprised of 14 men aged 45 - 60 years. Two series of laboratory analyses were performed. Independent tests were carried out at baseline and after 12 weeks of the experiment. The data were analyzed using Statistica 9.1 software. RESULTS A two-way repeated measures ANOVA revealed a statistically significant effect of the intervention programme on fat-free mass (η(2)=0.34), total body fat (η(2)=0.79), total cholesterol (η(2)=0.30), high-density lipoprotein cholesterol (η(2)=0.31), low-density...

Formulation pH has been reported to be responsible for the incidence of phlebitis. In this study, the effect of pH on injection phlebitis is investigated. Buffers of varying pHs were examined for their ability to produce phlebitis in rabbits. Thermal measurements as well as visual evaluations were used for phlebitis quantitation. The results show that formulation pH between 3.0 and 11.0 does not contribute to the incidence of phlebitis when administered as an iv bolus injection.

A validated HPLC method for the simultaneous determination of diminazene diaceturate and phenazone has been established for the analysis of the compounds in veterinary granules for injection and in bulk powders. The compounds were separated using a Symmetry RP 18 analytical column and detected by UV absorbance at 250 nm. Linearity, accuracy as well as the intra-assay precision, inter-day precision and specificity of the method were established. The limits of detection and quantification were 3.2 and 9.7 μg mL-1 for diminazene diaceturate and 9.57 and 28.99 μg mL-1 for phenazone. Method had the potential to determine these drugs simultaneously from dosage forms without any interference with each other.

Temperature-sensitive hydrogels composed of poly(N-isopropylacrylamide) (PNIPAAm) with chitosan (CPN) and chitosan+hyaluronic acid (CPNHA) were grafted in order to examine their physicochemical characteristics, in vitro drug release, and in vivo pharmacodynamics. The sol-gel transition behavior was investigated by UV/visible spectrophotometry, differential scanning calorimetry, and viscometry. A slight difference in the transition temperatures was observed among these polymer systems, with CPN and CPNHA exhibiting higher temperatures compared with PNIPAAm. A zeta potential determination revealed a positive charge for the CPN hydrogel, whereas no or only a negligible charge was observed for PNIPAAm and CPNHA. The entanglement of CPN hydrogels observed using scanning electronic microscopy showed the densest cross-linkage structure, followed by CPNHA and PNIPAAm. Both hydrophilic and lipophilic drugs, including nalbuphine, indomethacin, and the nalbuphine prodrug, were used as model drugs in an in vitro drug release experiment. All 3 hydrogels significantly prolonged drug release. The release rate of hydrophilic nalbuphine increased in the order CPN<CPNHA<PNIPAAm. The drug release of these hydrogels exhibited a trend opposite to that of lipophilic drugs. A cold ethanol tail-flick study was utilized in order to examine the antinociceptive activity of intravenous nalbuphine. CPN and CPNHA prolonged the analgesic duration of nalbuphine with no influence on the onset time. The loading of nalbuphine in the CPNHA hydrogel exhibited the longest analgesic duration (4h) among the 3 hydrogels tested.