Can liquorice extract and herbal solution prevent colonic mucosa damage caused by robenacoxib in dogs?

UNLABELLED: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in animals, especially in dogs, to manage pain due to inflammatory disease. This study investigated whether plant drugs can prevent mucosal injury induced by robenacoxib. We used fifteen healthy beagle dogs (7 male and 8 female) aged 4 months, weighing 4.2-5.1 kg at the beginning of the study. Endoscopy and biopsy of the colon were performed before and on the 21 day treatment with robenacoxib (1), robenacoxib, herbal solution with liquorice extract (2), placebo - an empty capsule (3). There were 5 animals in each group. The greatest microscopic damage in the colon was observed in animals which received robenacoxib. Plant drug administration reduced the severity of lesions in the colon when administered with robenacoxib (ARI = - 0.15). CONCLUSION: concurrent administration of liquorice extract and plant solution with robenacoxib was associated with significant decreased severity of the robenacoxib-induced colonic mucosal lesions.

Impact of pesticide contamination on aquatic microorganism populations in the littoral zone.

The effect of pesticide contamination of the littoral zone on the population of bacteria and fungi was analyzed using the example of a eutrophic water reservoir exposed for >30 years to the influence of expired crop-protection chemicals, mainly DDT. For three consecutive years, quantity analyses of bacteria and fungi were conducted and the composition of the microorganism population analyzed against seasonal dynamics. Mold and yeast-like fungi were also isolated and identified. Within the Bacteria domain, in addition to the large groups of microorganisms (Alphaprotobacteria, Betaprobacteria, and Gammaproteobacteria, Actinobacteria, and Cytophaga-Flavobacterium), the analysis also involved the presence of bacteria predisposed to degraded pesticides in natural environments: Pseudomonas spp. and Alcaligenes spp. The quantity dynamics of aquatic microorganisms indicated that bacteria and fungi under the influence of long-term exposure to DDT can adapt to the presence of this pesticide in water. No modifying effect of DDT was observed on the quantity of microorganisms or the pattern of seasonal relationships in the eutrophic lake. Changes were shown in the percentage share of large groups of bacteria in the community of microorganisms as was an effect of contamination on the species diversity of fungi. The data show the effectiveness of aquatic microorganism-community analyses as a tool for indicating changes in the water environment caused by pesticide contamination.

Investigation of the electronic, photosubstitution, redox, and surface properties of new ruthenium(II)-containing amphiphiles.

A series of pyridine- and phenol-based ruthenium(II)-containing amphiphiles with bidentate ligands of the following types are reported: [(L(PyI))Ru(II)(bpy)(2)](PF(6))(2) (1), [(L(PyA))Ru(II)(bpy)(2)](PF(6))(2) (2), [(L(PhBuI))Ru(II)(bpy)(2)](PF(6)) (3), and [(L(PhClI))Ru(II)(bpy)(2)](PF(6)) (4). Species 1 and 2 are obtained by treatment of [Ru(bpy)(2)Cl(2)] with the ligands L(PyI) (N-(pyridine-2-ylmethylene)octadecan-1-amine) and L(PyA) (N-(pyridine-2-ylmethyl)octadecan-1-amine). The imine species 3 and 4 are synthesized by reaction of [Ru(bpy)(2)(CF(3)SO(3))(2)] with the amine ligands HL(PhBuA) (2,4-di-tert-butyl-6-((octadecylamino)methyl)phenol), and HL(PhClA) (2,4-dichloro-6-((octadecylamino)methyl)phenol). Compounds 1-4 are characterized by means of electrospray ionization (ESI(+)) mass spectrometry, elemental analyses, as well as electrochemical methods, infrared and UV-visible absorption and emission spectroscopies. The cyclic voltammograms (CVs) of 1-2 are marked by two successive processes around -1.78 and -2.27 V versus Fc(+)/Fc attributed to bipyridine reduction. A further ligand-centered reductive process is seen for 1. The Ru(II)/Ru(III) couple appears at 0.93 V versus Fc(+)/Fc. The phenolato-containing 3 and 4 species present relatively lower reduction potentials and more reversible redox behavior, along with Ru(II/III) and phenolate/phenoxyl oxidations. The interpretation of observed redox behavior is supported by density functional theory (DFT) calculations. Complexes 1-4 are surface-active as characterized by compression isotherms and Brewster angle microscopy. Species 1 and 2 show collapse pressures of about 29-32 mN·m(-1), and are strong candidates for the formation of redox-responsive monolayer films.

The effect of isotonic multiple electrolyte infusions during anesthesia on blood gas and enzymatic values in horses.

General equine anesthesia is accompanied by the risk of complications and even death. The majority of general anesthetics used in veterinary practice lead to arterial hypotension, decreased capillary perfusion and ventilatory depression leading to pathological changes referred to as postanesthetic myopathy. In this study an attempt was made to analyze changes in the perioperative and postoperative acid-base equilibrium and blood enzymatic activity in horses, subject to the intensity of the applied fluid therapy. The horses were divided into two groups: I--administered Ringer's solution during surgery at a dose of 6-10 ml/kg BW/h, II--Ringer's solution administered at a dose of 12-15 ml/kg BW/h. The results of the study indicate that use of hydrating fluid infusions during general anesthesia, including infusions without hypertensive substances, minimizes the risk of myocyte damage due to disturbances in local and general blood circulation.

Platelet PD-L1 suppresses anti-cancer immune cell activity in PD-L1 negative tumors.

Strategies that interfere with the binding of the receptor programmed cell death protein-1 (PD-1) to programmed death ligand-1 (PD-L1) have shown marked efficacy against many advanced cancers, including those that are negative for PD-L1. Precisely why patients with PD-L1 negative tumors respond to PD-1/PD-L1 checkpoint inhibition remains unclear. Here, we show that platelet-derived PD-L1 regulates the growth of PD-L1 negative tumors and that interference with platelet binding to PD-L1 negative cancer cells promotes T cell-induced cancer cytotoxicity. These results suggest that the successful outcomes of PD-L1 based therapies in patients with PD-L1 negative tumors may be explained, in part, by the presence of intra-tumoral platelets. Altogether, our findings demonstrate the impact of non-cancer/non-immune cell sources of PD-L1 in the tumor microenvironment in the promotion of cancer cell immune evasion. Our study also provides a compelling rationale for future testing of PD-L1 checkpoint inhibitor therapies in combination with antiplatelet agents, in patients with PD-L1 negative tumors.

Intracranial self-stimulation in 3-day-old rat pups.

Three-day-old rat pups with electrodes directed at the medial forebrain bundle at the level of the lateral hypothalamic area were trained to push a paddle to receive electrical brain stimulation. Pups receiving stimulation that was contingent on lifting the paddle responded more frequently than did control pups and also learned a two-choice spatial discrimination task that was rewarded with brain stimulation. The experiments indicate that a neural substrate in the area of the medial forebrain bundle is involved in the central mediation of reinforcement in the rat pup.

Lactose drives Enterococcus expansion to promote graft-versus-host disease.

Disruption of intestinal microbial communities appears to underlie many human illnesses, but the mechanisms that promote this dysbiosis and its adverse consequences are poorly understood. In patients who received allogeneic hematopoietic cell transplantation (allo-HCT), we describe a high incidence of enterococcal expansion, which was associated with graft-versus-host disease (GVHD) and mortality. We found that Enterococcus also expands in the mouse gastrointestinal tract after allo-HCT and exacerbates disease severity in gnotobiotic models. Enterococcus growth is dependent on the disaccharide lactose, and dietary lactose depletion attenuates Enterococcus outgrowth and reduces the severity of GVHD in mice. Allo-HCT patients carrying lactose-nonabsorber genotypes showed compromised clearance of postantibiotic Enterococcus domination. We report lactose as a common nutrient that drives expansion of a commensal bacterium that exacerbates an intestinal and systemic inflammatory disease.

Continued challenges with the use of erythropoiesis-stimulating agents in patients with cancer: perspectives and issues on policy-guided health care.

Erythropoiesis-stimulating agents (ESAs) are approved as an alternative to blood transfusions for treating anemia secondary to chemotherapy in patients with cancer. Recently, ESAs have been a source of controversy and confusion in the oncology community. This began when two European trials-the Breast Cancer Erythropoietin Survival Trial (BEST) and the Advanced Head-and-Neck Cancer Treated with Radiotherapy (ENHANCE) Study-raised safety concerns about decreased overall survival and increased venous thromboembolic events. In 2004, the United States Food and Drug Administration (FDA) convened its Oncologic Drugs Advisory Committee (ODAC) to review the data and reassess the risks and benefits of ESAs in patients with cancer. On May 10, 2007, ODAC reconvened when five trials (BEST, ENHANCE, AMG-20010103, AMG-20000161, and EPO-CAN-20) showed decreased overall survival. The briefing document noted that studies demonstrating detrimental effects on survival and/or tumor outcomes used an unapproved treatment regimen designed to maintain hemoglobin levels above 12 g/dl. On May 14, 2007, just days after the ODAC reconvened, the Centers for Medicare and Medicaid Services (CMS) released a proposed decision memo for a national coverage determination (NCD) imposing restrictions on ESAs. For health care providers, aspects of the proposed NCD were markedly inconsistent with FDA-approved ESA use and generally were considered ambiguous and unclear. Over objections of several professional associations and members of Congress, on July 30, 2007, CMS posted the final NCD and declared it effective immediately. When compared with FDA-approved labeling and professional society guidelines, the NCD revealed differences in ESA initiation, dosage escalation, dosage reduction, and definition of response. These discrepancies have generated confusion among health care providers, who are struggling over whether they can feasibly provide a dual system of care-one for Medicare patients and another for non-Medicare patients-that is evidence based. With this supplement, we hope to educate health care providers on the issues and challenges associated with policy-guided health care when discrepancies exist between the policy and evidence-based practice; offer guidance on implementing the NCD; and highlight the important role of pharmacists in the process.

Cyclodialysis in the treatment of nonhealing secondary glaucoma.

In cases of glaucoma with elevated intra ocular pressure, the first objective of treatment is its reduction and normalization. In cases when excessive pressure has resulted in a loss of vision, the aim of treatment is to attenuate the pain and to improve the comfort of the patient. This paper presents a case of glaucoma secondary to anterior uveitis, resistant to pharmacological treatment. A gonioscopic examination in both eyes revealed a narrowed filtration angle. An ophthalmoscopic examination of the fundus showed partial retinal detachment. The cyclodialysis procedure was performed in both eyes. In the post-surgery period, intraocular pressure (IOP) in both eyes showed a downward tendency. The treatment of glaucoma secondary to anterior uveitis, particularly in its advanced state, often requires the combination of pharmacological treatment with a surgical procedure. Positive results in maintaining the patency of the fistula were observed after the application of a steroid therapy and a regular massage of filtration bleb, which significantly contributed to maintaining IOP at a desired level.

Short-term results of Ahmed glaucoma valve implantation in the surgical treatment of angle-recession glaucoma in dog.

Angle-recession glaucoma, being a consequence of blunt injury of an eyeball, is likely to develop in both a short or very distant period. The likelihood of the incidence of that condition in the clinical form is determined by the extent of injuries of ciliary cleft structures, especially of a trabecular meshwork. The manuscript reports a case of an early glaucoma secondary to a blunt injury of an eyeball with symptoms of angle recession to 300 degrees of periphery and intraocular pressure (IOP) at a level of 62 mmHg. The basic diagnostic examination that enables the evaluation of an angle, iris root and an opening to the ciliary cleft is gonioscopy. In case of a lack of response to the pharmacological reduction of IOP, a method of choice still remains a surgical procedure. In the reported case, a drainage procedure was applied in the form of implantation of the Ahmed valve prosthesis. Control tonometric examinations of the operated eye, performed over a 20-week period of postoperative management, demonstrated IOP at a level of 19 mmHg.

Good statistical practice in pharmacology. Problem 2.

BACKGROUND AND PURPOSE: This paper is intended to assist pharmacologists to make the most of statistical analysis and in avoid common errors. APPROACH: A scenario is presented where an experimenter performed an experiment to test the effects of two drugs on cultured cells. Analysis of the results, expressed as percentage of control, by a one-way ANOVA yielded P=0.058 and the experimenter concluded that neither drug was effective. The data were expressed as percentage of control because of pairing of the data within each experimental run, a common feature in cell culture experiments. Such data can be analysed with potentially more powerful ANOVA methods equivalent to the paired t-test. Monte Carlo simulations are presented to compare the power of relevant analyses. RESULTS: For data correlated within experimental run (i.e. paired values), transformation to percentage of control improved the power of a one-way ANOVA to detect a real effect, but a randomized block ANOVA (equivalent to a 2-way ANOVA with experiment and treatment as factors) using the raw values was substantially more powerful. The randomized block ANOVA performed well even with uncorrelated data, being only marginally less powerful than the one-way ANOVA. CONCLUSIONS AND IMPLICATIONS: A randomized block ANOVA is far superior to the one-way ANOVA with correlated data, and with uncorrelated data it is only marginally less powerful. Thus where there is, or might reasonably be, such a correlation (e.g. relatedness among the data within a single experimental run, or within a multi-well culture plate, or within an animal, et cetera), use the more powerful randomized block ANOVA rather than one-way ANOVA.

Good statistical practice in pharmacology. Problem 1.

BACKGROUND AND PURPOSE: This paper is intended to assist pharmacologists in making the most of statistical analysis and in avoiding common errors that can lead to false conclusions. APPROACH: A scenario is presented where a pathway inhibitor increased blood pressure responses to an agonist by about one third. The fictional experimenter concludes that the inhibitor enhanced the responses to the agonist, but has not applied any statistical analysis. Questions are asked of the reader, and a discussion of the author's answers is presented. RESULTS: The agonist responses have unequal standard errors, as often seen in data like these concentration-response curves with responses expressed as change from baseline. The uneven variability (heteroscedasticity) violates an assumption of conventional parametric statistical analyses, but can be corrected by data transformation. Expressing the data as absolute blood pressure and then transforming it to log blood pressure eliminated the heteroscedasticity, but made evident an effect of the inhibitor on baseline blood pressure. CONCLUSIONS AND IMPLICATIONS: Statistical analysis is a sensible precaution against mistakes, but cannot protect against all erroneous conclusions. In this scenario, the inhibitor reduced the blood pressure and increased responses to the agonist. However, it is likely that the latter effect was a consequence of the former and thus no conclusion can be safely drawn about any direct interaction between the agonist and the pathway inhibitor from this experiment. Where results are awkward to interpret because of confounding factors such as an altered baseline, statistical analysis may not be very useful in supporting a safe conclusion.

Impact of delayed insemination on pregnancy rates to gender selected semen in a fixed-time AI system.

The objectives of the current experiment were to determine if delaying insemination by 8 h in a FTAI protocol would alter estrus expression and pregnancy rates in cows inseminated with sex-sorted semen, characterize bull variation in pregnancy rates to sex-sorted semen and examine the impact of repeated years of FTAI to sex-sorted semen on calving distribution. Over three breeding seasons, postpartum cows (n = 839) were estrous synchronized using the 5-day CO-Synch + CIDR system. Cows were given GnRH (100 µg i.m., Factrel) at time of insertion of a controlled internal drug releasing device (CIDR; Eazi-Breed CIDR). Five d later CIDR was removed and PGF2α (25 mg i.m., Lutalyse) was given at removal and 8 h later. Estrus detection aids were applied at CIDR removal. Cows were inseminated with X-sorted or Y-sorted sex-sorted semen at 72 h (NORM) or 80 h (DELAY) after CIDR removal, and GnRH was administered at AI. At insemination, estrus status was categorized as positive (YES), partial (QUES), unknown (NR) or negative (NO). Bulls were introduced to cows at 14 d and removed at 60 d after FTAI. Pregnancy diagnosis was performed by ultrasound at d 60 after FTAI and via palpation at 60 d after bull removal. There was no difference (P > 0.05) in pregnancy rates to sex-sorted semen or final pregnancy rates between NORM and DELAY cows. Pregnancy to sex-sorted semen averaged 35.2% whereas final pregnancy rates were 90.6%. More cows (P < 0.05) in the DELAY group expressed estrus before FTAI, but this increase did not alter pregnancy rates to sex-sorted semen. Expression of estrus before FTAI increased (P < 0.02) pregnancy rates to sex-sorted semen across treatments with differences being YES > QUES or NR > NO. There was considerable variation in pregnancy rate by bull (P < 0.05) with pregnancy rates ranging from 55.6% to 19.3%. Whole herd calving distribution was altered (P < 0.05) after 3 y of use of sex-sorted semen compared to the previous 3 y when conventional semen was used. We conclude that delaying insemination by 8 h in an FTAI protocol did not improve pregnancy rates to sex-sorted semen despite more cows exhibiting estrus before FTAI. In addition, a high bull to bull variation in pregnancy rates to sex-sorted semen is a limitation in FTAI systems. Further research into FTAI strategies for use with sex-sorted semen is warranted.

Role of disulfide bridges in the folding, structure and biological activity of omega-conotoxin GVIA.

Omega-Conotoxin GVIA (GVIA), an N-type calcium channel blocker from the cone shell Conus geographus, is a 27 residue polypeptide cross-linked by three disulfide bonds. Here, we report the synthesis, structural analysis by (1)H NMR and bioassay of analogues of GVIA with disulfide bridge deletions and N- and C-terminal truncations. Two analogues that retain the crucial Lys-2 and Tyr-13 residues in loops constrained by two native disulfide bridges were synthesised using orthogonal protection of cysteine residues. In the first analogue, the Cys-15-Cys-26 disulfide bridge was deleted (by replacing the appropriate Cys residues with Ser), while in the second, this disulfide bridge and the eight C-terminal residues were deleted. No activity was detected for either analogue in a rat vas deferens assay, which measures N-type calcium channel activity in sympathetic nerve, and NMR studies showed that this was due to a gross loss of secondary and tertiary structure. Five inactive analogues that were synthesised without orthogonal protection of Cys residues as part of a previous study (Flinn et al. (1995) J. Pept. Sci. 1, 379-384) were also investigated. Three had single disulfide deletions (via Ser substitutions) and two had N- or C-terminal deletions in addition to the disulfide deletion. Peptide mapping and NMR analyses demonstrated that at least four of these analogues had non-native disulfide pairings, which presumably accounts for their lack of activity. The NMR studies also showed that all five analogues had substantially altered tertiary structures, although the backbone chemical shifts and nuclear Overhauser enhancements (NOEs) implied that native-like turn structures persisted in some of these analogues despite the non-native disulfide pairings. This work demonstrates the importance of the disulfides in omega-conotoxin folding and shows that the Cys-15-Cys-26 disulfide is essential for activity in GVIA. The NMR analyses also emphasise that backbone chemical shifts and short- and medium-range NOEs are dictated largely by local secondary structure elements and are not necessarily reliable monitors of the tertiary fold.

Ciprofloxacin versus trimethoprim/sulfamethoxazole for prophylaxis of bacterial infections in bone marrow transplant recipients: a randomized, controlled trial.

PURPOSE: To compare the efficacy and safety of ciprofloxacin (CIP) and trimethoprim/sulfamethoxazole (TMS) for the prevention of bacterial infections in patients who received bone marrow transplantation (BMT) for the treatment of solid and hematopoietic neoplasms. PATIENTS AND METHODS: Adult inpatients about to undergo BMT for lymphoma, leukemia, or solid tumors were enrolled onto a prospective, randomized, double-blinded, controlled trial that compared CIP (750 mg orally twice per day) with TMS (160 mg trimethoprim and 800 mg sulfamethoxazole orally twice per day). Subjects were stratified before randomization according to tumor and BMT type. Prophylaxis was begun within 96 hours of initiation of the BMT preparative regimen and continued until the onset of fever, signs or symptoms of infection, serious adverse effects, or recovery of the absolute granulocyte count (AGC) to > or = to 400/microL. RESULTS: Seventy-five CIP recipients and 71 TMS recipients were assessable for efficacy. No difference was noted between the two groups in occurrence of fever during neutropenia, time to onset of first fever, or overall infection rates. Ten bacteremias occurred in CIP recipients versus six in TMS recipients (P = .43). Ten episodes of Clostridium difficile enterocolitis occurred in TMS recipients versus no episodes in CIP recipients (P = .001). Four infections caused by gram-negative bacilli, including one bacteremia, occurred in TMS recipients versus none in CIP recipients (P = .06). No differences were noted in the incidence of rash or organ toxicity. TMS recipients had longer durations of granulocytopenia at AGC levels < or = to 500/microL and < or = to 100/microL than did CIP recipients (P = .08 for both comparisons). Mean peak and trough serum levels of CIP decreased significantly between weeks 1 and 2 of prophylaxis. CONCLUSION: CIP and TMS were equally safe and effective in the prevention of bacterial infections in BMT patients when the overall infection rate was used as the principal end point. TMS prophylaxis was associated with a higher incidence of C difficile enterocolitis and infections caused by gram-negative bacilli, as well as a trend toward prolongation of granulocytopenia.

Analysis of competitive agonist-antagonist interactions by nonlinear regression.

The rigorous estimation of a dissociation constant (Kb) for antagonists in functional assays has been sought by pharmacologists using a variety of techniques ever since the regression method of Arunlakshana and Schild in 1959. Here, Michael Lew and James Angus describe a simplified global regression method with improved accuracy compared to Schild analysis. The method is suitable for personal computers with standard graphing and statistical software. The accuracy of the predicted pKb values and confidence intervals has been tested by comparing examples of published data, and by mathematical (bootstrap) simulations.

Dynamic mechanisms of non-classical antagonism by competitive AT(1) receptor antagonists.

Selective competitive angiotensin AT(1) receptor antagonists exhibit diverse patterns of antagonism of angiotensin-II-mediated responses in functional assays. These range from the classical parallel rightward shift of agonist concentration-response curves with no depression of the maximum response to an apparently straightforward insurmountable antagonism with complete depression of the maximum response and no rightward shift. This article reviews some earlier equilibrium-based models that have been used to explain the insurmountable antagonism, and suggests that a kinetic model might provide a more satisfactory account of the observations. Such a model might provide deeper insights into the pharmacology of G-protein-coupled receptors than the more popular equilibrium models.

Pneumococcal aortitis in the antibiotic era.

The pneumococcus remains in the antibiotic era a formidable pathogen, capable of atypical, lethal clinical presentations. We report two fatal cases of thoracic aortitis caused by Streptococcus pneumoniae in the setting of bacteremic illness from this pathogen. One case occurred in an aortic graft and the other arose in a native aorta. We also discuss the indolent clinical presentation and the diagnostic failure of transesophageal echocardiography and leukocyte scintigraphy. Persistent pyrexia with atypical chest pain and unexplained blood loss should alert clinicians to the possibility of this uncommon, yet lethal complication of pneumococcal disease.

Laparoscopic removal of gastric foreign bodies in dogs--comparison of manual suturing and stapling viscerosynthesis.

This study was an attempt to evaluate the application of various laparoscopic techniques of removing foreign bodies from the stomach in dogs in comparison to conventional laparotomy. The research was conducted on two groups of 10 dogs each with clinically confirmed foreign bodies in the stomach. In case of all patients, a laparoscopic instrument, EndoBag, was used for the removal of the foreign body from the stomach and the abdominal cavity. Manual suturing with the use of Szabo-Berci suturing kit was used for the gastrotomy wound closure in group I. In group II, linear staplers were used for viscerosynthesis. All patients were subjected to radiological assessment of tightness of anastomosis. No significant differences between the quality of the performed stomach anastomosis were shown. Therefore, the competitiveness of an economical manual suturing in comparison with the very expensive mechanical suturing preferred in human surgery was confirmed. The described procedures of laparoscopic gastrotomy seem to be applicable for removing foreign bodies from the stomach in a clinical veterinary practice.

Laparoscopic cryptorchidectomy in dogs --report of 15 cases.

The study aimed at determining the usability of laparoscopic cryptorchidectomy in treating cases of simple cryptorchidism and neoplastic testes in dogs. The presence of one or both testes inside the peritoneal cavity was confirmed in this study by an ultrasonographic examination employing the use of a 6.5 MHz convex head. The surgeries were conducted on a group of 15 dogs. In 12 subjects a one-sided cryptorchidism was found, 9 of which had right-sided cryptorchidism. In 3 dogs, both-sided cryptorchidism was observed. In 3 cases, an increase in the size of the abdominal testes with the symptoms of hyperestrogenism and feminisation raised a suspicion of neoplastic changes (SCT) taking place, which was confirmed by a histopathological examination. A laparoscopic cryptorchidectomy with intracorporal ligation was performed in all the subjects. The spermatic cord and ductus deferens were occluded with a ligature of an absorbable material, and a manually applied knot.