The efficacy of raw and concentrated bentonite clay in reducing the toxic effects of aflatoxin in broiler chicks.

The objective of this study was to evaluate the efficacy of two adsorbents, a raw bentonite clay (RC) and a concentrated bentonite clay (CC), in ameliorating the toxic effects of aflatoxin B1 (AFB1). Results of the in vitro study (pH 3.0) indicated the CC adsorbed more AFB1 than RC (93.39 mg/g vs. 79.30 mg/g) suggesting that CC may be more effective than RC in reducing the toxic effects of AFB1. One hundred and eighty day-old straight run broiler chicks were assigned to 6 replicate pens of 5 chicks each and assigned to 6 dietary treatments from hatch to day 21. Dietary treatments included: 1) basal diet (BD) containing no AFB1 or adsorbents; 2) BD plus 0.50% RC; 3) BD plus 0.50% CC; 4) BD plus 2.0 mg AFB1/kg; 5) BD plus 2.0 mg AFB1/kg plus 0.50% RC; and 6) BD plus 2.0 mg AFB1/kg plus 0.50% CC. Dietary AFB1 concentrations were confirmed by analysis and diets were screened for other mycotoxins prior to the start of the experiment. The addition of AFB1 to the feed reduced (P < 0.05) growth performance and increased (P < 0.05) relative liver weight (RLW) and kidney weight (RKW) of chicks fed AFB1 compared to control chicks on day 21. These changes were ameliorated (P < 0.05) by the addition of RC and CC to the AFB1 diet. Mild to moderate lesions of aflatoxicosis (2.25) were observed in chicks fed AFB1 alone on day 21. The addition of both RC and CC to the AFB1 diet decreased (P < 0.05) but did not prevent liver lesions (0.92 and 1.42, respectively). Results indicate that both RC and CC were effective in reducing the toxic effects of AFB1, however the cost of processing of CC would make the RC a more economical product for reducing the effects of AFB1 in young broiler chicks.

Compatibility studies between mannitol and omeprazole sodium isomers.

Omeprazole, commonly used in the treatment of various gastrointestinal disorders degrades rapidly in acidic pHs and results in inter-individual variability due to different rates of metabolism amongst patients. Since S-omeprazole shows more predictable bioavailability and excipients have been known to interact with active pharmaceutical ingredients to produce altered bioavailability, it was decided to investigate the compatibility of omeprazole sodium isomers with mannitol, the major excipient in omeprazole formulations using differential scanning calorimetry (DSC) for bulk drug, attenuated total reflectance (ATR) infrared (IR) spectroscopy in a powder mixture and localized thermal analysis (LTA) from a drug disk. DSC results clearly indicate an interaction between mannitol and R-omeprazole sodium due to decreased melting temperatures and broadening peaks. The DSC of S-omeprazole sodium does not show melting temperature although the drug was crystalline. Because of the accelerated temperature conditions during DSC experiments applied in this work, ATR-IR was undertaken to determine whether these results occurred at room temperature for the solid dosage form. The ATR-IR results show a difference between R- and S-omeprazole sodium with mannitol by the appearance of both the amino (N-H) and imino (N-H) stretching frequencies for R-omeprazole and only the N-H for the S-omeprazole sodium. It may thus be concluded that different ratios for the tautomeric forms for S- and R-omeprazole sodium result in changes in the degree of crystallinity and are responsible for the interaction with mannitol, common excipient in formulation. These interactions may be directly related to the difference in terms of bioavailability.

A matrix effect in pectin-rich fruits hampers digestion of allergen by pepsin in vivo and in vitro.

BACKGROUND: It is a general belief that a food allergen should be stable to gastric digestion. Various acidic plant polysaccharides, including pectin, are ubiquitous in fruit matrixes and can form hydrogels under low-pH conditions. OBJECTIVE: The purpose of this study was to investigate the effect of hydrogel forming polysaccharide-rich fruit matrixes on in vivo gastric and in vitro pepsic digestion of fruit allergens. METHODS: Fruit extract proteins (kiwi, banana, apple and cherry) and a purified major kiwi allergen Act c 2 were digested with simulated gastric fluid in accordance with the US Pharmacopeia. In vivo experiments on kiwi fruit digestion were performed on four healthy non-atopic volunteers by examining the gastric content 1 h after ingestion of kiwi fruit. The Act c 2 and kiwi proteins were detected in immunoblots using monoclonal anti-Act c 2 antibodies and rabbit polyclonal antisera. RESULTS: Crude fruit extracts were resistant to digestion by pepsin when compared with commonly prepared extracts. In the gastric content of all volunteers, following kiwi fruit ingestion and immunoblotting, intact Act c 2 was detected with anti-Act c 2 monoclonal antibodies, while kiwi proteins of higher molecular weights were detected using rabbit polyclonal antisera. Addition of apple fruit pectin (1.5% and 3%) to the purified kiwi allergen was able to protect it from pepsin digestion in vitro. CONCLUSION: The matrix effect in pectin-rich fruits can influence the digestibility of food proteins and thereby the process of allergic sensitization in atopic individuals.

Reappraisal of the quantity and nature of renal calcifications and mineral metabolism in the magnesium-deficient rat. Effects of treatment with potassium citrate or the combination magnesium citrate and potassium citrate.

There is an urgent need for drugs capable of inhibiting renal calcifications, nephrocalcinosis and stones included, in humans. Current anticalcification medication is based mainly on alkalinization of the metabolism using potassium-containing citrate alone, despite the fact that calcium stone patients suffer marginally from both magnesium and potassium deficiency. We investigated the anticalcification efficacy of oral potassium citrate versus the combined administration of this drug and magnesium citrate in the magnesium-deficient rat developing corticomedullary nephrocalcinosis and luminal microliths in the long term. Among other things we employed specific stains for calcium and oxalate, light microscopy and element analysis for renal tissue and calcifications, respectively. In addition, minerals in renal tissue, urine and plasma were determined, as well as the state of extracellular calcium homeostasis. Magnesium deficiency caused pure calcium phosphate tissue deposits, containing no magnesium, but no deposition of calcium oxalate in the tubular lumen; tissue magnesium, calcium and phosphorus were increased, and there was marked potassium wastage via urine; despite mild hypercalcemia other signs of hyperparathyroidism were not found. Alkalinization with the two kinds of medication evoked an increase in urinary pH, citrate, and potassium; however, potassium citrate alone tended to aggravate renal concretions, whereas the combination of this drug with magnesium citrate completely prevented concretions. It was concluded that: (1) magnesium deficiency-induced calcifications are oxalate-free and are not sensitive to mobilization by alkalinization with potassium citrate, which might explain the failure of the drug to prevent stone recurrence in clinical stone patients, and (2) the combination of potassium citrate and magnesium citrate, which shows enormous anticalcification efficacy, deserves high priority in clinical trials aimed at evaluating strategies for the prevention of stones.

[Mechanisms of the favorable effect of spinal anesthesia in traumatic shock]. / Mechanizmi povoljnog efekta spinalne anestezije u traumatskom soku.

Changes in the level of total peptidoleukotriens-pLT (LTC4 + LTD4 + LTE4) and inositol triphosphates (IP3) were analyzed in the thalamus of rats subjected to "tourniquet" trauma of both hind extremities (LD50) depending on the power of afferent nociceptive nerve impulses. Prevention of spreading, i.e., reduction of painful impulses from the damaged regions was achieved by the spinal anesthesia with bupivacain-chloride immediately after removal of the rubber bandage. Together with pLT and IP3 levels determined by radio immunoassay, physiologic parameters (mean arterial pressure, blood-brain barrier permeability) were also analyzed. Morphologic changes in the thalamus of rats were analyzed by electron microscopy. Extreme increase of the thalamic pLT and IP3 levels in traumatized animals together with increased blood-brain barrier permeability were found. Spinal anesthesia prevented, i.e., reduced these pathologic changes. Authors conclude that afferent painful impulses cause pLT increase in the thalamus and could modify CNS response to the trauma.

'Therapeutic window's for multiple drug treatment of experimental cerebral ischemia in gerbils.

The effects of the following drugs: nimodipine (1 mg/kg b.w., i.p.), 2-amino-5-phosphonovaleric acid (4 mg/kg b.w., i.p.) and propentofylline (25 mg/kg b.w., i.p.), administered (alone or in combination) at the end of 15 min bilateral ischemia in gerbils were evaluated on mitochondrial superoxide dismutase (SOD), glutathione reductase (GR), glucose-6 phosphate dehydrogenase (G6PD), monoamine oxidase (MAO) activities, and thiobarbituric acid reactive material (TBARM), and brain water content at 1 hour of reperfusion. The combined treatment virtually abolished early postischemic brain edema (4.1% v.s. 0.6%) and efficiently counteracted ischemia-induced changes [decreased SOD (79% v.s. 98%), GR (52% v.s. 105%) and MAO (25% v.s. 79%), and increased TBARM (198% v.s. 108%)]. The same combination of drugs administered 15 min before ischemia had a similar effect (e.g., reduced brain swelling and lipid peroxidation) as when given at the end of ischemia, whereas a limited or absent impact was seen when the drugs were given 15 min or 1 hour after ischemia, respectively. The data suggest that (post)ischemic brain swelling and mitochondrial dysfunction can be reduced by drugs which synchronously prevent processes induced in the early stages of reperfusion.

[Mechanisms of the beneficial effect of indomethacin and nimodipine in the treatment of traumatic shock in rats]. / Mehanizmi povoljnog efekta indometacina i nimodipina u lecenju traumatskog soka kod pacova.

Aiming to study the pathogenetic mechanisms of the disturbed function of the central nervous system in traumatic shock we have determined the dynamics of changes of eicosanoids (PGF2 alpha, TxB2, 6-keto-PGF1 alpha, peptidoleukotrienes) in the brain structures (medulla oblongata, hypothalamus) of the experimental animals subjected to bilateral trauma of the hind legs (tourniquet trauma, LD50). Considering that our previous data have shown the importance of eicosanoid mediatory system in the pathogenetic mechanisms of shock, we have studied possible use of prostaglandin synthesis inhibitors (indomethacin) and calcium channel antagonists (nimidipine) in traumatic shock. The authors have concluded that in the pathogenetic mechanism of the disturbed function of the CNS in traumatic shock the important role has peptidoleukotrienes as well as that the combined use of prostaglandin synthesis inhibitors and antagonists of voltage-dependent calcium channel would be useful in the therapy of the injured patients.

[The importance of physical therapy in the treatment of Volkmann's contracture in children]. / Znacaj fizikalne terapije u lecenju Folkmanove kontrakture kod dece.

Over the period from 1981 to 1991 twenty-eight children were treated for neurovascular posttraumatic complications (Volkman's contracture), in the Centre for rehabilitation and physical medicine of the Children's surgical department in Belgrade. The success of the treatment depended on how a patient was examined for the first time, and how soon a proper diagnosis was established. On the basis of our experience we insist on an early physical treatment, i.e. while the injured segment is immobilized. An early kinesitherapy followed later by electrotherapy, parafino-therapy, vitamin B therapy and use of corrective plaster cast splints is the best way in treating lesions. The treatment lasted from 3 to 6 months depending on the seriousness of an injury. If there was no good result with physical therapy we carried out surgery followed by physical therapy upon the removal of immobilisation devices.

[Esmolol--beta-adrenergic blocking agent with ultrashort action]. / Esmolol--novi beta adrenergicki blokator sa ultrakratkim delovanjem.

Esmolol is a new, highly efficient, cardioselective beta-adrenergic receptor blocking agent for intravenous use only. Its action commences rapidly and its duration is very short (about 15 min). It is very quickly metabolized in the body into an inactive product, and hence its therapeutic effect can be easily controlled. Indications for its use are supraventricular tachyarrhythmias and hypertension during the perioperative period and noncompensated sinus tachycardia. Esmolol is considered as drug of choice in its indicational domain and hence it is being introduced into materia medica in the increasing number of countries. Its therapeutic range is wide. Hypotension is the most frequent side effect of esmolol, while bradycardia, congestive heart failure, hypotension and cardiogenic shock are the most important contraindications for its use.