Needless Injections

Adsorption or catalytic decomposition of labile substances by the syringe needle can be a problem for some compounds using hot vaporizing injectors [25]. For open tubular columns deactivated fused silica syringe needles and cold on-column Injection techniques are used to minimize this problem. Alternatively, syringes fitted with a needle shroud for cold-needle injection can be used [26]. 

Hot needle Injection follows the general procedure described... 

Using a sterile, nonpyrogenic disposable syringe and needle, inject 5.0 ml of pyrogen-free water to reconstitute the reagent. Reconstitution is more rapid if reagents are at room temperature. 

Basic Protocol 3 is a rapid GC method to evaluate limonene purity. The needle is coated with a residual limonene layer in the syringe. The sample volatilizes into the column in which the sensitivity of GC detectors (FID) provides a reliable indication of purity. This is known as a wet needle injection. 

Tanghe, A., Denis, O., Lambrecht, B., Motte, V., van den Berg, T. and Huygen, K. (2000) Tuberculosis DNA vaccine encoding Ag85A is immunogenic and protective when administered by intramuscular needle injection but not by epidermal gene gun bombardment. Infect Immun., 68, 3854-3860. 

Williams, J., Fox-Ley va, L., Christensen, C., Fisher, D., Schlicting, E., Snowball, M. etal. (2000) Hepatitis A vaccine administration comparison between jet-injector and needle injection. Vaccine, 18,1939-1943. 

Using a sterile 5 ml syringe and 20 G needle, inject 5 ml of sterile PBS into, and aspirate out of, the peritoneal cavity twice. 

Silylation is often used for the preparation of the derivatives of pharmaceuticals. In addition to the above-mentioned examples, it was applied to the GC—MS of cambenda-zole [561], the TMS derivatives of which were prepared by heating for 30 min at 60°C with BSA in pyridine. Lauwereys and Vercruysse [562] analysed different hypnotica and carried out the silylation directly on the point of the needle in the falling needle injection system (see p. 22). In order to obtain good reproducibility of the method, they recommended conventional silylations as alternative procedures. Anticonvulsant drugs were also silylated with the aid of BSA and analysed on 5% of OV-101 [563]. 

Verhagen, A. Ebels, J.T. Dogterom, A.A. Jonkman, J.H. Pharmacokinetics and pharmacodynamics of a single dose of recombinant human growth hormone after subcutaneous administration by jet-injection comparison with conventional needle-injection. Eur. J. Clin. Pharmacol. 1995, 49 (1-2), 69-72. 

Oberye, J. Mannaerts, B. Huisman, J. Timmer, C. Local tolerance, pharmacokinetics, and dynamics of ganirelix (Orgalutran) administration by Medi-Jector compared to conventional needle injections. Hum. Reprod. 2000, 15 (2), 245-249. 

Transdermal vaccination or transcutaneous immunization, is attractive, because it does not require specially trained personnel necessary for needle injections. Topical application of antigens to intact skin has shown promising results for the administration of DNA-based vaccines. Noninvasive gene delivery by pipetting adenovirus- or liposome-complexed plasmid DNA onto the outer layer of skin was able to achieve localized transgene expression within a restricted subset of skin in mice. It also elicited an immune response against the protein encoded by the DNA. ... 

Penile shaft lichen sclerosus has been reported in a 63-year-old man in association with alprostadil intraca-vernous injection for erectile dysfunction (5). The authors suggested that the lichen sclerosus had been caused by (1) an isomorphic response to the trauma of repeated needle injection (2) a local cutaneous response to alprostadil-induced collagen synthesis or alprostadil-induced fibroblast production of IL-6, with secondary paracrine/ autocrine-induced collagen synthesis by improper skin exposure by direct injection to the skin or by retrograde flow of alprostadil through the needle puncture tract or (3) a random occurrence of separate events. 

Verzele et al.2 concluded that the "cold on-column" injection, applied for the piperine assay, and the "falling needle" injection, applied for the quinine-quinidine assay, are the best alternative at the moment for quantitative capillary gas chromatography. They are applicable to high temperature capillary gas chromatography, but they also have their limitations. 

Edlund described a method for simultaneous determination of morphine, 6-0-acetyl morphine and codeine in human plasma or blood. The samples were buffered to pH 9 and extracted on silica columns, cleaned by extraction and finally acylated with pentafluoropropionic anhydride. The derivatives formed were separated on a glass capillary column (25 m by 0.36 mm I.D., coated with OV-1) at 220°C. The falling needle injection and electron capture detection were used. Although degradation of the solutes was observed, the degradation observed was very reproducible, so that quantitative analyses could be carried out in spite of the degradation. The author recommended regular control and calibration in order to obtain reliable results. 

The fact that cells with transgene expression are found only in close proximity to the track of the needle injection indicates that dispersion of the injected plasmid DNA within the organ is an important issue and that mechanical force caused by the needle injection is critical for the effective intracellular delivery of naked plasmid DNA. Direct needle injection of plasmid DNA to the target organ is apparently simple and easy. Furthermore, muscle and skin are very attractive tissues as injection sites because surgery is not required for the administration of the DNA to these sites. 

As far as your stomach and intestines are concerned, peptide drugs like BST and insulin are just tiny protein snacks which are very effectively digested into nutritious amino acids. If these drugs could be absorbed intact, then people suffering from diabetes would be eating insulin pills rather than using or receiving painful hypodermic needle injections. 

Hot needle Injection follows the general procedure described for the cold needle method except that prior to depressing the plunger the needle is allowed to heat up in the injector for 3-5 seconds. 

The most common alternative to needle injection is the gene gun, which propels gold beads coated with DNA directly into cells in the skin. As described above, resident LG are transfected, then migrate to the draining lymph node whereupon naive lymphocytes are primed. Because of the greater efficiency with which DNA... 

Local intramuscular injection of plasmid DNA or adenoviral vectors encoding vascular epithelial growth factor or fibroblast growth factor, both able to induce the formation of new blood vessels, have been used to improve microcirculation in ischemic tissue. Needle injection of plasmid DNA has been used in leg muscle, catheter application or needle injection was also tried in ischemic heart muscle. The formation of new blood vessels and an improvement in the microcirculation has been observed. 

An important breakthrough in this area occurred with the discoveiy that the type IV injection system of H. pylori crosses the inner and outer membrane of the bacteria, and, like a needle, inject Cag A into the cytosol of host gastric epithelial cells. Recent reports revealed that Cag A protein would be phosphorylated on tyrosine residues by yet unidentified host cell kinases. It was further shown that phosphorylated Cag A induces cytoskeletal changes that in turn induce cell elongation, cell spreading, and production of filopodia and lamellipodia. These data indicate that Cag A-mediated epithelial responses are at least partly independent of inflammation, although H. pylori vimlence is associated with the presence of cag PAI. 

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