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Objective: In this study, the common aerobic Gram-positive bacteria (GPB) contaminating veterinary clinic surfaces were isolated, and their susceptibility to antimicrobial agents (antibiotics and biocides) was determined. Materials and Methods: Standard cultural and biochemical procedures were used to process 62 swab samples collected from different surfaces in 4 veterinary clinics for the isolation and identification of GPB. The agar dilution technique was used to determine the sensitivity of the isolates to disinfectants, while the disc diffusion technique was used to determine the sensitivity to antibiotics. Results: Isolation rates in veterinary clinics I, II, III, and IV were 39.4%, 40.4%, 7.4%, and 12.8%, respectively. GPB were isolated from all the surfaces sampled. A total of 94 GPB isolates were recovered, comprising Bacillus species (51.1%), Staphylococcus species (38.3%), Corynebacterium species (6.4%), and Enterococcus species (4.3%). Only 13.8% of the GPB were resistant to at least one of the biocides tested. Multiple drug resistance to at least three classes of antimicrobial agents was exhibited by 95% of the isolates tested. Conclusion: The results of this study suggest that veterinary clinic environments and surfaces in Makurdi are reservoirs of wide varieties of antimicrobial-resistant GPB of veterinary and public health importance. [Vet. Res. Notes 2023; 3(11.000): 86-94]

Objective: Many reports of bacteriuria in domestic animals allude that animals may serve as hosts and means of spreading zoonotic pathogenic and multidrug-resistant bacteria via contamination of the environment with their urine. This cross-sectional study determined the bacterial load of urine from slaughtered cattle. It investigated the resistance to antimicrobials and pathogenicity potentials of the Gram-negative bacteria recovered from urine samples. Materials and Methods: Urine samples were obtained from 52 slaughtered cattle at the Wurukum Abattoir, Makurdi, Benue State, within a month. Standard microbiological procedures were used to process the samples for the isolation and identification of bacteria. Disc diffusion technique was used to determine the antibiogram of the isolates. Standard procedures also were deployed to examine the expression of virulence factors. Results: Bacteria were isolated from 20 of the 52 urine samples, with the positive samples yield¬ing total aerobic and coliform counts of 2.8 × 103 − 9.1 ×105 and 2.5 × 102 − 3.3 × 105 CFU/ml, respectively. Species of Gram-negative bacilli identified were Escherichia coli (n = 10), Tatumella ptyseous (n = 4), Acinetobacter baumannii (n = 2), and Klebsiella pneumoniae (n = 1). The isolates were all resistant to at least three antimicrobial classes. All the isolates were resistant to the bac¬tericidal action of the serum, while 2 (11.8%) were hemolytic on blood agar. Conclusion: Adequate veterinary examination of slaughtered cattle before presenting for slaugh¬ter is imperative to reduce the contamination of the meat and environment with the urine of cattle with elevated levels of bacteriuria. [Vet. Res. Notes 2023; 3(5.000): 36-42]

Size exclusion (SE) high performance liquid chromatography (HPLC) is widely used for the molecular size distribution (MSD) analyses of various therapeutic proteins. We report development and validation of a SE-HPLC method for MSD analyses of immunoglobulin G (IgG) in products using a TSKgel SuperSW3000 column and eluting it with 0.4M NaClO 4 , a chaotropic salt, in 40mM phosphate buffer, pH 6.8. The chromatograms show distinct peaks of aggregates, tetramer, and two dimers, as well as the monomer and fragment peaks. In addition, the method offers about half the run time (12min), better peak resolution, improved peak shape and more stable base-line compared to HPLC methods reported in the literature, including that in the European Pharmacopeia (EP). A comparison of MSD analysis results between our method and the EP method shows interactions between the protein and the stationary phase and partial adsorption of aggregates and tetramer on the stationary phase, when the latter method is used. Thus, the EP method shows lower percent of aggregates and tetramer than are actually present in the products. In view of the fact that aggregates have been attributed to playing a critical role in adverse reactions due to IgG products, our observation raises a major concern regarding the actual aggregate content in these products since the EP method is widely used for MSD analyses of IgG products. Our method eliminates (or substantially reduces) the interactions between the proteins and stationary phase as well as the adsorption of proteins onto the column. Our results also show that NaClO 4 in the eluent is more effective in overcoming the protein/column interactions compared to Arg-HCl, another chaotropic salt. NaClO 4 is shown not to affect the molecular size and relative distribution of different molecular forms of IgG. The method validated as per ICH Q2(R1) guideline using IgG products, shows good specificity, accuracy, precision and a linear concentration dependence of peak areas for different molecular forms. In summary, our method gives more reliable results than the SE-HPLC methods for MSD analyses of IgG reported in the literature, including the EP, particularly for aggregates and tetramer. The results are interpreted in terms of ionic (polar) and hydrophobic interactions between the stationary phase and the IgG protein., (Published by Elsevier B.V.)

Determinants of amphetamine (AMPH)-induced neurotoxicity are poorly understood. The role of lipopolysaccharides (LPS) and organ injury in AMPH-induced neurotoxicity was examined in adult male Sprague-Dawley rats that were give AMPH and became hyperthermic during the exposure. Environmentally-induced hyperthermia (EIH) in the rat was compared to AMPH to determine whether AMPH-induced increases in LPS and peripheral toxicities were solely attributable to hyperthermia. Muscle, liver, and kidney function were determined biochemically at 3h or 1 day after AMPH or EIH exposure and histopathology at 1 day after treatment. Circulating levels of LPS were monitored (via limulus amoebocyte coagulation assay) during AMPH or EIH exposure. Blood LPS levels were detected in 40-50% of the AMPH and EIH rats, but the presence of LPS in the serum had no effect on organ damage or striatal dopamine depletions (neurotoxicity). In both CR and NCTR rats, serum bound urea nitrogen and creatinine levels increased at 3h after EIH or AMPH (2- to 3-fold above control) but subsided by 1 day. Alanine transaminase was increased (indicating liver dysfunction) by both AMPH and EIH at 3 h (2- to 10-fold above control) in CR rats, but the levels were not significantly different between the control and AMPH groups in NCTR animals. Mild liver necrosis was detected in 1 of 7 rats examined in the AMPH group and in 1 of 5 rats examined in the EIH group (only NCTR rats were examined). Serum myoglobin increased (indicating muscle damage) in both CR and NCTR rats at 3h and was more pronounced with AMPH (≈5-fold above control) than EIH. Our results indicate that: (1) "free" blood borne LPS often increases with EIH and AMPH but may not be necessary for striatal neurotoxicity and CNS immune responses; (2) liver or kidney dysfunction may result from muscle damage; however, it is not sufficient nor necessary to produce, but may exacerbate, neurotoxicity; (3) AMPH-induced serum myoglobin release is a potential biomarker and possibly a factor in AMPH-induced toxicity processes., (Published by Elsevier B.V.)

This video presentation was created to show a method of harvesting the two most important highly vascular structures, not residing within the brain proper, that support forebrain function. They are the cerebral surface (superficial) vasculature along with associated meninges (MAV) and the choroid plexus which are necessary for cerebral blood flow and cerebrospinal fluid (CSF) homeostasis. The tissue harvested is suitable for biochemical and physiological analysis, and the MAV has been shown to be sensitive to damage produced by amphetamine and hyperthermia. As well, the major and minor cerebral vasculatures harvested in MAV are of potentially high interest when investigating concussive types of head trauma. The MAV dissected in this presentation consists of the pial and some of the arachnoid membrane (less dura) of the meninges and the major and minor cerebral surface vasculature. The choroid plexus dissected is the structure that resides in the lateral ventricles as described by Oldfield and McKinley. The methods used for harvesting these two tissues also facilitate the harvesting of regional cortical tissue devoid of meninges and larger cerebral surface vasculature, and is compatible with harvesting other brain tissues such as striatum, hypothalamus, hippocampus, etc. The dissection of the two tissues takes from 5 to 10 min total. The gene expression levels for the dissected MAV and choroid plexus, as shown and described in this presentation can be found at GSE23093 (MAV) and GSE29733 (choroid plexus) at the NCBI GEO repository. This data has been, and is being, used to help further understand the functioning of the MAV and choroid plexus and how neurotoxic events such as severe hyperthermia and AMPH adversely affect their function.

Previous studies focusing on amphetamine (AMPH), methamphetamine (METH) and methylphenidate (MPH) neurotoxicity have almost exclusively been conducted in rodents during the light cycle, which is when most rodents sleep. There are virtually no studies that have simultaneously compared the effects of these three stimulants on body temperature and also determined serum stimulant levels during exposure. The present study compared the effects of MPH, AMPH and METH treatment on body temperature and neurotoxicity during the waking (dark) cycle of the rat. This was done to more effectively replicate stimulant exposure in waking humans and to evaluate the relative risks of the three stimulants when taken inappropriately or non-therapeutically (e.g., abuse). Four subcutaneous injections (4×), at 2 h intervals, were used to administer each dose of the stimulants tested. Several equimolar doses for the three stimulants were chosen to produce plasma levels ranging from 3 times the highest therapeutic levels (no effect on body temperature) to those only attained by accidental overdose or intentional abuse in humans. Either 4×2.0 mg/kg AMPH or 4×2.2 mg/kg METH administered during the waking cycle resulted in peak serum levels of between 1.5 and 2.5 μM (4 to 5 times over maximum therapeutic levels of METH and AMPH) and produced lethal hyperthermia, 70% striatal dopamine depletions, and neurodegeneration in the cortex and thalamus. These results show that METH and AMPH are equipotent at producing lethal hyperthermia and neurotoxicity in laboratory animals during the wake cycle. Administration of either 4×2.2 or 4×3.3 mg/kg METH during the sleep cycle produced lower peak body temperatures, minimal dopamine depletions and little neurodegeneration. These findings indicate that administration of the stimulant during the waking cycle compared to sleep cycle may significantly increase the potency of amphetamines to produce hyperthermia, neurotoxicity and lethality. In contrast, body temperature during the waking cycle was only significantly elevated by MPH at 4×22 mg/kg, and the serum levels producing this effect were 2-fold (approximately 4.5 μM) greater on a molar basis than hyperthermic doses of AMPH and METH. Thus, AMPH and METH were equipotent on a mg/kg body weight basis at producing hyperthermia and neurotoxicity while MPH on a mg/kg body weight basis was approximately 10-fold less potent than AMPH and METH. However, the 10-fold lower potency was in large part due to lower plasma levels produced by MPH compared to either AMPH or METH., (Published by Elsevier Inc.)

Mutated Cu/Zn superoxide dismutase (SOD1) was the first proven cause of amyotrophic lateral sclerosis (ALS) and was the basis for the first animal model. Many approaches, including transgenic and knock-out animals, cell models, and in vitro studies using recombinant hSOD1 mutants and wild-type, have been employed in an attempt to elucidate the gained toxic function. However, a thorough characterization of the properties of hSOD1 mutants produced in vivo has yet to be carried out, primarily due to the lack of a procedure capable of purifying the enzyme from relevant tissues in a manner that avoids potential artifacts. Here we report a new, one-step purification procedure using a semi-preparative polymeric reversed-phase HPLC system, which yields greater than 99% pure enzyme from the spinal cord, and >95% pure from brain, heart, and kidney. This novel approach for purifying 'in vivo expressed' native dimeric SOD1 will facilitate the determination of the true 'as isolated' properties of the enzyme that is responsible for disease, devoid of any expression system, or harsh purification, artifacts. An important new finding related to the specific activity of human SOD1 (normalized to copper content) is also discussed.

The dietary polyphenols trans-resveratrol [5-[(1E)-2-(4-hydroxyphenyl)ethenyl]-1,3-benzenediol; found in red wine] and curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1E,6E-heptadiene-3,5-dione] (found in curry powders) exert anti-inflammatory and antioxidant effects via poorly defined mechanisms. It is interesting that cannabinoids, derived from the marijuana plant (Cannabis sativa), produce similar protective effects via CB1 and CB2 receptors. We examined whether trans-resveratrol, curcumin, and ASC-J9 [1,7-bis(3,4-dimethoxyphenyl)-5-hydroxy-1E,4E,6E-heptatriene-3-one] (a curcumin analog) act as ligands at cannabinoid receptors. All three bind to human (h) CB1 and mouse CB1 receptors with nanomolar affinities, displaying only micromolar affinities for hCB2 receptors. Characteristic of inverse agonists, the polyphenols inhibit basal G-protein activity in membranes prepared from Chinese hamster ovary (CHO)-hCB1 cells or mouse brain that is reversed by a neutral CB1 antagonist. Furthermore, they competitively antagonize G-protein activation produced by a CB1 agonist. In intact CHO-hCB1 cells, the polyphenols act as neutral antagonists, producing no effect when tested alone, whereas competitively antagonizing CB1 agonist mediated inhibition of adenylyl cyclase activity. Confirming their neutral antagonist profile in cells, the polyphenols similarly attenuate stimulation of adenylyl cyclase activity produced by a CB1 inverse agonist. In mice, the polyphenols dose-dependently reverse acute hypothermia produced by a CB1 agonist. Upon repeated administration, the polyphenols also reduce body weight in mice similar to that produced by a CB1 antagonist/inverse agonist. Finally, trans-resveratrol and curcumin share common structural motifs with other known cannabinoid receptor ligands. Collectively, we suggest that trans-resveratrol and curcumin act as antagonists/inverse agonists at CB1 receptors at dietary relevant concentrations. Therefore, these polyphenols and their derivatives might be developed as novel, nontoxic CB1 therapeutics for obesity and/or drug dependence.

In an attempt to augment the efficacy of 7-chloro 4-aminoquinoline analogs and also to overcome resistance to antimalarial agents, we synthesized three cyclen (1,4,7,10-tetraazacyclododecane) analogs of chloroquine [a bisquinoline derivative, 7-chloro-4-(1,4,7,10-tetraaza-cyclododec-1-yl)-quinoline HBr, and a 7-chloro-4-(1,4,7,10-tetraaza-cyclododec-1-yl)-quinoline-Zn(2+) complex]. The bisquinoline displays the most potent in vitro and in vivo antimalarial activities. It displays 50% inhibitory concentrations (IC(50)s) of 7.5 nM against the D6 (chloroquine-sensitive) clone of Plasmodium falciparum and 19.2 nM against the W2 (chloroquine-resistant) clone, which are comparable to those of artemisinin (10.6 and 5.0 nM, respectively) and lower than those of chloroquine (10.7 and 87.2 nM, respectively), without any evidence of cytotoxicity to mammalian cells, indicating a high selectivity index (>1,333 against D6 clone and >521 against W2 clone). Potent antimalarial activities of the bisquinoline against chloroquine- and mefloquine-resistant strains of P. falciparum were also confirmed by in vitro [(3)H]hypoxanthine incorporation assay. The in vivo antimalarial activity of the bisquinoline, as determined in P. berghei-infected mice, is comparable to that of chloroquine (50% effective dose,

The isoquinuclidine (2-azabicyclo[2.2.2]octane) ring system may be viewed as a semi-rigid boat form of the piperidine ring and, when properly substituted, a scaffold for rigid analogs of biologically active ethanolamines and propanolamines. It is present in natural products (such as ibogaine and dioscorine) that display interesting pharmacological properties. In this study, we have expanded our continuing efforts to incorporate this ring system in numerous pharmacophores, by designing and synthesizing semirigid analogs of the antimalarial drug chloroquine. The analogs were tested in vitro against Plasmodium falciparum strains and Leishmania donovani promastigote cultures. Compounds 6 and 13 displayed potent antimalarial activity against both chloroquine-susceptible D6 and the -resistant W2 strains of P. falciparum. All analogs also demonstrated significant antileishmanial activity with compounds 6 and 13 again being the most potent. The fact that these compounds are active against both chloroquine-resistant and chloroquine-sensitive strains as well as leishmanial cells makes them promising candidates for drug development.

The brain continues to remain an area where little corrective surgery can be performed. Recently, the ability to reverse some brain damage and perhaps prevent further damage has moved closer to hospitals and clinics. Several agents demonstrating neuroprotective properties and even neural regeneration have been developed to the extent that they have been granted patent protection, one of the first steps in commercial development. The concept of neuroprotection is the administration of an agent that can reverse some of the damage or prevent further damage. Some agents offer protection against cell degeneration due to oxidative stress whilst other agents specifically protect against neural stroke damage. In the early years of neuroprotective research, most compounds were not designed as such but were found to possess neuroprotective activity in later studies. However, the original structures have since become the leads for purely synthetic derivatives. Most of the agents are or were designed from biologically active natural products, either plant extracts or endogenous peptides/proteins and even sequences of RNA. This review will present the most recently patented neuroprotective agents.

The synthesis of 10 G*PE analogues, wherein the glycine residue has been modified, is described by coupling readily accessible dibenzyl-L-prolyl-L-glutamate 2 with various analogues of glycine. Pharmacological evaluation of the novel compounds was undertaken to further understand the role of the glycine residue on the observed neuroprotective properties of the endogenous tripeptide GPE.

The brain remains an area where little corrective surgery can be performed and the reversal of damage is almost impossible. Recently, reports of agents offering neuroprotection have begun to appear in the literature. The concept of neuroprotection is the administration of some agent, which should reverse some of the damage or prevent further damage. Some agents offer protection against cell degeneration to the neuronal cells. Still other agents specifically protect the dopamine neurons and the retina. The majority of neuroprotective agents are antioxidants. An immunosuppressive calcineurin inhibitor, NOS inhibitor, sigma-1 modulator, AMPA antagonist and Ca2+ channel blocker have all shown neuroprotective activity. An estrogen agonist and two glycoprotein IIb/IIIa antagonists also exhibit neuroprotective activity. Most of the synthetic compounds presented were not originally designed as neuroprotective agents but were found to possess neuroprotective activity in later studies. Many of these compounds are biologically active natural products, either plant extracts or endogenous peptides/proteins. This review will present the most recent reports on these agents.

Chemical substance abuse has tormented mankind throughout history. A number of chemical approaches have been employed in an attempt to treat chemical addiction. Unfortunately, most of these have proven unsuccessful though several chemical entities have been shown to be moderately effective. The naturally occurring alkaloid ibogaine has been reported to interrupt the cravings for alcohol, cocaine and opiates. Other alkaloids from Tabernanthe iboga, such as ibogamine and tabernanthine, provide insight into the structure activity relationship at the different receptors believed to be involved in addiction. The synthetic iboga alkaloid congener, 18-MC, also shows potential as an anti-addictive agent without the hallucinogenic effects of ibogaine. Additionally, acamprosate, BP 897, GBR12909, lofexidine and memantine have shown promising results in the treatment of addiction. All of these leads provide a start for the medicinal chemist to design anti-addictive agents, since currently no drugs are approved in the U.S. for the treatment of addictions to cocaine, methamphetamine, other stimulants or PCP.

In the late 20(th) century, the treatment of cancer began to include its prevention. Today, compounds exist that will lower the risk of developing certain types of cancer. This has been demonstrated in studies where chemically induced tumor growth has been slowed or reversed. Anti-inflammatory compounds having chemopreventive activity are piroxicam, sulindac, aspirin, celecoxib and curcumin. The selective estrogen receptor modulators, tamoxifen and raloxifene, are beneficial in the prevention of estrogen dependent tumors. Retinoids, vitamin A derivatives, such as targretin and fenretinide are useful in the prevention of tumors. Compounds containing sulfur, such as sulforaphane and oltipraz, are even useful as radioprotective agents. The steroid dehydroepiandosterone can inhibit experimental carcinogenesis. All of these chemical classes provide a start for the medicinal chemist to design more effective chemopreventive agents. The biomarkers used to determine the chemopreventive activity of new compounds are quite often activities of enzymes. The identification of those individuals at high risk is still in its infancy and presents a troubling dilemma.

Eleven direct refractory dies were made from separate polysulfide rubber impressions of two Dentoform teeth which had been prepared for porcelain-fused-to-gold veneer crowns with labial porcelain shoulders. Porcelain veneer crowns were built and fired directly on the dies, following the manufacturer's instructions and using a common laboratory technique. The finished crowns were seated on the Dentoform teeth, and the porcelain-tooth adaptation was measured with a micrometer eyepiece in a dissecting microscope. In general, the study indicated that by use of a direct refractory die, the porcelain adaptation of an average porcelain shoulder veneer crown could be made to fall within the tolerances of a clinically acceptable gold margin (39 mu).21 The crown could likewise be made to adapt closer than the normal thickness of cement film may allow (20 to 40 mu).22 However the adaptation of many crowns was more uneven than the above statements would tend to indicate. The study also showed that with great care and a limited number of firings, margins of a lesser thickness than a piece of 0.001 inch (25.4 mu) platinum foil could be attained. There appears to be promise in the use of a direct refractory die material. However, more studies are needed to overcome some of the problems in the technique described.