Hyaluronidase additional

Pillwein, K. et ah, Hyaluronidase additional to standard chemotherapy improves outcome for children with malignant brain tumors. Cane. Lett., 131, 101, 1998. 

Aqueous solutions of some drugs are so unstable that chemical stabilization is impossible. In this case the dmg itself, not its aqueous solution, is sterilized by dry heat (160°C for 2 hours or its equivalent at higher temperatures) in its final container and dissolved immediately before use by the addition of sterile water (Water for Injechons BP). For dmgs which are both thermolabile and unstable in aqueous solution, a sterile soluhon of the dmg is freeze-dried in the final container and is reconstimted as above just before use (e.g. many anhbiotics, Hyaluronidase BP). 

As described above, cancer cells produce or induce other cells to produce hyalurooan. This halo of hyaluronan protects the cells against macrophages or leukocytes and shields them from cytostatics. Several studies have dealt with the addition of hyaluronidase to chemotherapy in order to degrade the hyaluronan coaling and to render the cells more accessible to the cytostatic drugs. 

Stem et aL [149] made use of a hyaluronan-binding protein obtained from the tryptic digestion of the proteoglycan core protein of bovine nasal cartilage to detect hy alumni da sc activities in urine samples from wiles tumor patients. The pathophysiology of this tumor is associated with major alterations in the metabolism of hyaluiouan, and it is thought that urinary hyaluronidase can be used as an additional marker. 

Interactions other than in the gut are exemplified by the use of hyaluronidase to promote dissipation of a s.c. injection, and by the addition of vasoconstrictors, e.g. adrenaline, felypressin, to local... 

In the past, when intravascular injection proved difficult, contrast media were sometimes given by the subcutaneous or intramuscular routes. On occasion, severe sloughing of tissue resulted. Addition of hyaluronidase in order to alleviate this problem only aggravated it, and dilution with water, saline, or procaine solution also proved useless. If, in exceptional circumstances, these routes have to be used, the medium should be injected in small quantities at multiple sites. 

Systemic hypersensitivity reactions are not a frequent problem in local anesthesia. Systemic toxicity or allergy to additives (hyaluronidase, bisulfate, parabens) has sometimes been mistakenly classified as hypersensitivity to local anesthetics (SEDA-17,135) (29). WeU-documented case reports are very few, relating particularly to the older aminoesters this appears to be because these agents have the highly antigenic para-aminobenzoic acid as a metabolite (SEDA-13, 98). The incidence of true allergy is actually very low, probably less than 1% of all the adverse effects attributable to these substances (SEDA-20, 123). 

Intradermal local anesthetic solutions can cause considerable pain on injection. Additives, such as hyaluronidase, which are used to enhance the analgesic effect of local anesthetics, can often exacerbate this (165). Infiltration from the inside of a wound can be less painful than through intact skin (166). 

Among several antidotes for the treatment of vinca alkaloid extravasation, hyaluronidase is the most effective (79). Seven patients with extravasation of vincristine, vinblastine, or vinorelbine received hyaluronidase 250 units diluted in 6 ml of 0.9% saline, through the indwelling needle or, when the needle had been already removed, as six subcutaneous injections around the extravasation site. None developed skin necrosis. Local mild skin warming in order to produce local vasodilatation may have an additional beneficial effect, but should be avoided when simultaneous extravasation of a vinca alkaloid and an anthra-cycline is suspected, because local warming can worsen the anthracycline-associated local reaction, whereas local cooling, which is generally beneficial in anthracycline-related extravasation alone, can worsen skin necrosis due to vinca alkaloids (76). 

The activity of the local anesthetics is enhanced by increased extraneuronal pH and by coadministration of a vasoconstrictor (e.g. epinephrine (adrenaline)) or hyaluronidase. Sodium channel blockade is pH dependent, increasing when the pH is alkaline, and can be reduced in disease conditions associated with acid pH (e.g. inflammation). The addition of bicarbonate (e.g. to lidocaine) speeds up the onset and prolongs the duration of action. If bicarbonate is added to... 

C. perfringens is the most important of the histotoxic clostridia that cause tissue infections in humans, especially of the muscle tissue (clostridial myonecrosis or gas gangrene). The organism is more aerotolerant than most other anerobes. In addition to toxins and enzymes, many of which have lethal, cell-destroying and hemolytic properties, a number of nonlethal enzymes are also produced and apparently contribute to the invasiveness of the organism in the tissue. These include collagenase, deoxyribonuclease, and hyaluronidase. 

Histochemically, mucopolysaccharides outlining the epidermal cells can easily be seen (B28, G9, S23, S25, W19). In addition, Flesch and Esoda (F14) found evidence of a glycoproteolipid in normal stratum corneum and increased amounts in psoriatic scale. They could find no sialic acid in the material, it was resistant to hyaluronidase, and they proposed that a lack of proper breakdown of this material was important in the pathophysiology of the disease. 

Hyaluronidase has found applications as an additive to the anesthetic agents used for peribulbar anesthesia for vitreoretinal surgery. Combinations of hyaluronidase with bupivacaine [119], lidocaine and epinephrine [120], lignocaine and adrenaline [121], or lidocaine and bupivacaine [122] were judged very... 

I. Thomson. Addition of hyaluronidase to lignocaine with adrenaline for retrobulbar anaesthesia in the surgery of senile cataract. Br. J. Ophthalmology 72 700 (1988). 

In most animal parasitic nematodes, pharyngeal glands secrete digestive enzymes onto ingested food particles as they enter the pharynx. In A. suum, an esterase, amylase, maltase, protease, peptidase and lipase are secreted into the pharynx during feeding. The pharynx of species that feed on host mucosal cells may also contain hyaluronidase and additional enzymes specialized for digestion of host tissues (141). 

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