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Animal Data (animal + data)
Selected AbstractsPaternal contribution to fetal alcohol syndromeADDICTION BIOLOGY, Issue 2 2004Ernest Abel Maternal alcohol use during pregnancy is associated with a wide range of adverse outcomes for the child. Many women who drink during pregnancy also have male partners who abuse alcohol. Existing data on paternal effects of alcohol abuse during the preconceptual period and at the time of conception are reviewed. Epidemiological data offer some support for a paternal influence on birth weight, congenital heart defects, and some evidence of mild cognitive impairments. Animal data have demonstrated decreased litter size, increased prevalence of low birth weight fetuses and mixed data on risk of malformations. Increased susceptibility to Pseudomonas bacterial infection has been reported. Cognitive and behavioral findings are the most robust effects. These include learning and memory deficits, hyperactivity, and poor stress tolerance. Multiple causal mechanisms for a paternal effect have been suggested, but none seems satisfactory to explain all findings. Further research is needed on paternal effects in animals and human populations. The results of this research may influence prevention activities. [source] Localization, Etiology and Impact of Calcium Phosphate Deposits in Renal AllograftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 11 2009P. Evenepoel Hypercalcemia, hypophosphatemia and renal phosphate wasting are common after kidney transplantation. Animal data suggest that these alterations in mineral metabolism may contribute to calcium phosphate (CaPhos) deposition in the kidney and renal dysfunction. We tested the hypothesis that CaPhos deposition is highly prevalent in the early posttransplant period and is related to a disturbed mineral metabolism. For this purpose, biomarkers of mineral metabolism and renal calcium and phosphorus handling were prospectively assessed in 201 renal transplant recipients. CaPhos deposits were observed in 4.6, 30.4 and 24.7% of protocol biopsies obtained at the time of engraftment, and 3 and 12 months thereafter, respectively. In multivariate logistic regression analysis, high calcium and low serum phosphorus levels were independently associated with renal CaPhos deposition at month 3. The extent of CaPhos deposition correlated significantly with the severity of mineral metabolism disturbances. Renal function after a mean follow-up of 33 months was similar in patients with and without CaPhos deposition at month 3. In conclusion, our data demonstrate that CaPhos deposition is highly prevalent in the early posttransplant period and suggest that a disordered mineral metabolism is implicated in its pathogenesis. The clinical relevance of CaPhos deposition remains to be established. [source] The effects of mild induced hypothermia on the myocardium: a systematic reviewANAESTHESIA, Issue 5 2010F. E. Kelly Summary Mild induced hypothermia improves neurological outcome and reduces mortality among initially comatose survivors of out-of-hospital cardiac arrest. Similar pathological processes occur in the heart and the brain, namely ischaemia followed by reperfusion injury. Animal data indicate that mild induced hypothermia results in improved myocardial salvage, reduced infarct size, reduced left ventricular remodelling and better long-term left ventricular function. Several small human studies suggest that infarct size may be reduced by mild induced hypothermia, although this has not reached significance in any human study to date. There are variable reports of harm to the myocardium caused by mild induced hypothermia, including reduced myocardial contractility and cardiac output, electrocardiographic changes and arrhythmias, especially bradycardia. These harmful effects are reversible with rewarming. [source] Decreased Dopamine D2/D3-Receptor Binding in Temporal Lobe Epilepsy: An [18F]Fallypride PET StudyEPILEPSIA, Issue 8 2006Konrad J. Werhahn Summary:,Purpose: Although animal data are suggestive, evidence for an alteration of the extrastriatal dopaminergic system in human focal epilepsy is missing. Methods: To quantify D2/D3-receptor density, we studied seven patients with temporal lobe epilepsy (TLE) and nine age-matched controls with positron emission tomography (PET) by using the high-affinity dopamine D2/D3-receptor ligand [18F]Fallypride ([18F]FP) suitable for imaging extrastriatal binding. TLE was defined by interictal and ictal video-EEG, magnetic resonance imaging (MRI), and [18F]fluorodeoxyglucose ([18F]FDG)-PET and was due to hippocampal sclerosis (HS), based on histology in all patients. Primary analysis was based on regions of interest (ROIs) defined on individual MRIs. For each patient, binding potential (BP) was calculated by using the simplified reference tissue model, and the epileptogenic was compared with the unaffected hemisphere in each ROI. To confirm the results, an additional voxel-based group analysis was performed by using statistical parametric mapping. Results: Compared with controls, [18F]FP BP was significantly decreased in the epileptogenic temporal lobe in all patients. On ROI analysis, this reduction was evident in areas surrounding the seizure-onset zone at the pole (,34.2%) and lateral aspects (,32.9%) of the temporal lobe. Although the hippocampus [18F]FDG uptake (,8.1%) and hippocampal MR volume (,35.1%) were significantly reduced, no significant decrease of [18F]FP BP was found. Reduction of [18F]FP BP did not correlate with hippocampal atrophy. Conclusions: D2/D3-receptor binding is reduced at the pole and in lateral aspects of the epileptogenic temporal lobe in patients with mesial TLE and HS. This area might correspond to "the irritative zone," indicating that D2/D3 receptors might play a specific role in the pathophysiology of mesial TLE. [source] REVIEW: Human and laboratory rodent low response to alcohol: is better consilience possible?ADDICTION BIOLOGY, Issue 2 2010John C. Crabbe ABSTRACT If people are brought into the laboratory and given alcohol, there are pronounced differences among individuals in many responses to the drug. Some participants in alcohol challenge protocols show a cluster of ,low level of responses to alcohol' determined by observing post-drinking-related changes in subjective, motor and physiological effects at a given dose level. Those individuals characterized as having low level of response (LR) to alcohol have been shown to be at increased risk for a lifetime diagnosis of alcohol dependence (AD), and this relationship between low LR and AD appears to be in part genetic. LR to alcohol is an area where achieving greater consilience between the human and the rodent phenotypes would seem to be highly likely. However, despite extensive data from both human and rodent studies, few attempts have been made to evaluate the human and animal data systematically in order to understand which aspects of LR appear to be most directly comparable across species and thus the most promising for further study. We review four general aspects of LR that could be compared between humans and laboratory animals: (1) behavioral measures of subjective intoxication; (2) body sway; (3) endocrine responses; and (4) stimulant, autonomic and electrophysiological responses. None of these aspects of LR provide completely face-valid direct comparisons across species. Nevertheless, one of the most replicated findings in humans is the low subjective response, but, as it may reflect either aversively valenced and/or positively valenced responses to alcohol as usually assessed, it is unclear which rodent responses are analogous. Stimulated heart rate appears to be consistent in animal and human studies, although at-risk subjects appear to be more rather than less sensitive to alcohol using this measure. The hormone and electrophysiological data offer strong possibilities of understanding the neurobiological mechanisms, but the rodent data in particular are rather sparse and unsystematic. Therefore, we suggest that more effort is still needed to collect data using refined measures designed to be more directly comparable in humans and animals. Additionally, the genetically mediated mechanisms underlying this endophenotype need to be characterized further across species. [source] REVIEW: Acute withdrawal, protracted abstinence and negative affect in alcoholism: are they linked?ADDICTION BIOLOGY, Issue 2 2010Markus Heilig ABSTRACT The role of withdrawal-related phenomena in the development and maintenance of alcohol addiction remains under debate. A ,self-medication' framework postulates that emotional changes are induced by a history of alcohol use, persist into abstinence, and are a major factor in maintaining alcoholism. This view initially focused on negative emotional states during early withdrawal: these are pronounced, occur in the vast majority of alcohol-dependent patients, and are characterized by depressed mood and elevated anxiety. This concept lost popularity with the realization that in most patients, these symptoms abate over 3,6 weeks of abstinence, while relapse risk persists long beyond this period. More recently, animal data have established that a prolonged history of alcohol dependence induces more subtle neuroadaptations. These confer altered emotional processing that persists long into protracted abstinence. The resulting behavioral phenotype is characterized by excessive voluntary alcohol intake and increased behavioral sensitivity to stress. Emerging human data support the clinical relevance of negative emotionality for protracted abstinence and relapse. These developments prompt a series of research questions: (1) are processes observed during acute withdrawal, while transient in nature, mechanistically related to those that remain during protracted abstinence?; (2) is susceptibility to negative emotionality in acute withdrawal in part due to heritable factors, similar to what animal models have indicated for susceptibility to physical aspects of withdrawal?; and (3) to what extent is susceptibility to negative affect that persists into protracted abstinence heritable? [source] "Unknown Risks" of non-steroid topical medications for atopic dermatitisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2007Anne Marie McNeill PhD Introduction, Tacrolimus ointment is a nonsteroid treatment for atopic dermatitis which is both effective and has a minimal side-effect profile. However, some clinicians may be reluctant to use tacrolimus ointment due to the "unknown risks", meaning those that have not been uncovered in human studies conducted thus far. Therefore, the available animal data regarding the "unknown risks" of topical tacrolimus therapy are reviewed, and a discussion of the interpretation of this available but limited data is presented. Animal studies, Some of the fear on the part of clinicians regarding the use of topical tacrolimus may come from the results of animal studies which showed an increase in lymphoma and UV-induced skin cancer after treatment with topical tacrolimus in animal models of carcinogenesis. However, rigorous assessment of these studies suggest that it is somewhat likely that these represent a species-specific response to tacrolimus in an animal already predisposed to tumor formation, and therefore may not be relevant in assessing the possibility of an increased human health risk. Conclusions, Animal and human studies suggest that topical tacrolimus is a safe alternative to topical steroids, with the major known adverse effect being a transient burning sensation, compared with the known adverse effects of topical steroids, including long-lasting ones. Therefore, in the opinion of the authors, currently available data, including animal studies, does not suggest that "unknown risks" of topical tacrolimus need be any more concerning than the known side-effects of the topical steroids. [source] A male bovine linkage map for the ADR granddaughter designJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 5 2000H. Thomsen Summary The aim of this paper is to present the construction of a male genetic linkage map as a result of the bovine genome mapping project, which is a common effort of the German cattle breeding federation (ADR), four animal breeding institutes, three blood group laboratories and two animal data and breeding value evaluation centres. In total 20 grandsires with 1074 sires were provided from the German cattle population as reference families, 16 of these paternal half-sib groups are German Holstein families (DH), three are German Simmental (ST) families, and one is a Brown Swiss family (BS). Of 265 markers included in the linkage map, 248 were microsatellite markers, five were bovine blood group systems, eight SSCP markers and four proteins and enzymes. More than 239 000 genotypes resulted from typing the offspring for the respective markers and these were used for the construction of the map. On average 478 informative meioses were provided from each marker of the map. The summarized map length over all chromosomes was 3135.1 cM with an average interval size of 13.34 cM. About 17, 35.7 and 79.1% of the map intervals showed a maximum genetic distance between the adjacent markers of 5, 10 and 20 cM, respectively. The number of loci ranged from two (pseudoautosomal region of the sex chromosome, BTAY) to 15 (BTA23) with an average of 8.8 markers per chromosome. Comparing the length of the chromosomes shows variation from 49.6 cM for BTA26 to 190.5 cM for BTA1 with a mean of 107.7 cM for all autosomes of the genetic linkage map. It was possible to identify chromosomal discrepancies in locus order and map intervals by comparison with other published maps. The map provided sufficient marker density to serve as a useful tool for a scan of segregating quantitative trait loci. Zusammenfassung Im vorliegenden Artikel wird die Erstellung der genetischen Markerkarten für das Rindergenom im Rahmen des Genomanalyseprojektes der Arbeitsgemeinschaft Deutscher Rinderzüchter (ADR) vorgestellt. Auf der Basis des ,Granddaughter Designs' wurde ein Familienmaterial bestehend aus 20 väterlichen Halbgeschwistergruppen mit 1074 Söhnen für die Typisierung mit genetischen Markern bereitgestellt. Insgesamt 16 dieser paternalen Halbgeschwisterfamilien lassen sich der Rasse Deutsche Holsteins zuordnen, drei Familien entstammen der Rasse Deutsches Fleckvieh, und eine Familie gehört der Rasse Deutsches Braunvieh an. Dabei variiert die Anzahl der Söhne von 19,128 pro Vater. Für die Typisierung wurden 248 Mikrosatellitenmarker aus bereits publizierten Karten ausgewählt. Zusätzlich konnten 8 SSCP-und RFLP Marker, 5 Blutgruppensysteme und 4 Proteinmarker zur Entwicklung der genetischen Karte herangezogen werden. Die Anzahl der Marker variierte von 2 (pseudoautosomaler Bereich des Geschlechtschromosoms) bis 15 (Chromosom 23), wobei durchschnittlich 8.8 genetische Marker pro Chromosom typisiert wurden. Im Durchschnitt lieferten die genetischen Marker 478 informative Meiosen pro Marker. Alle Typisierungsergebnisse wurden in die Kieler Markerdatenbank übertragen und auf etwaige Fehler geprüft. Als Ergebnis konnten die genetischen Karten für alle 29 Autosomen und den pseudoautosomalen Bereich des Geschlechtschromosoms erstellt werden. Dabei wurde ein Bereich von 3135.1 cM des Rindergenoms abgedeckt, wobei die Länge des durchschnittlichen Markerintervalls 13.34 cM beträgt. Die Längen der Chromosomen zeigten eine Variation von 49.6 cM für Chromosom 26 bis zu 190.5 cM für Chromosom 1. Aufgrund der Anzahl informativer Meiosen und der Markerdichte bildet diese genetische Markerkarte in gutes Instrument für eine genomweite Suche nach segregierenden Genorten, die für die Variation von quantitativen Merkmalen verantwortlich sind. [source] Pharmacokinetics of liquiritigenin in mice, rats, rabbits, and dogs, and animal scale-upJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2009Hee E. Kang Abstract Pharmacokinetics of liquiritigenin (LQ) and its two glucuronide metabolites, M1 and M2, in mice, rats, rabbits, and dogs and animal scale-up of the pharmacokinetic parameters of LQ were evaluated. After intravenous administration of LQ, the AUC (AUC0,t) values of LQ, M1, and M2 were proportional to LQ doses in all animals studied. Animal scale-up of some pharmacokinetic parameters of LQ was performed based on the parameters after its intravenous administration (20 mg/kg; in the linear pharmacokinetic range) to the four species. Linear relationships were obtained (r,>,0.968) between log CL (or CL/fu) (L/h) and log species body weight (W) (kg) [CL (or CL/fu),=,3.29 (34.0) W0.723 (0.789)] and log,Vss (or Vss/fu) (L) and log,W (kg) [Vss (or Vss/fu),=,0.340 (3.52) W0.882 (0.948)]. Interspecies scale-up of plasma concentration,time data of LQ using apolysichron (complex Dedrick plots) resulted in similar profiles, and plasma concentration,time profile of humans were predicted using the well-fitted four animal data. Our results indicate that the LQ data obtained from laboratory animals could be utilized to generate preliminary estimates of the pharmacokinetic parameters of LQ in humans. These parameters can serve as guidelines for better planning of clinical studies. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4327,4342, 2009 [source] The correction factors do help in improving the prediction of human clearance from animal dataJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 5 2005Iftekhar Mahmood First page of article [source] Intestinal Dysbiosis: A Possible Mechanism of Alcohol-Induced Endotoxemia and Alcoholic Steatohepatitis in RatsALCOHOLISM, Issue 10 2009Ece Mutlu Background:, Clinical and animal data indicate that gut-derived endotoxin and other luminal bacterial products are necessary cofactors for development of alcoholic liver disease (ALD). Although gut leakiness is clearly an important cause of endotoxemia in ALD, it cannot fully explain endotoxemia in all ALD subjects and thus other factors may be involved. One possible factor is a change in gut microbiota composition (dysbiosis). Thus, the aim of our study was to interrogate the gut bacterial microbiota in alcohol-fed rats to see if chronic alcohol consumption affects gut bacteria composition. Method:, Male Sprague,Dawley rats were given either alcohol or dextrose intragastrically by gavage twice daily for up to 10 weeks. A subgroup of rats was also given either a probiotic (lactobacillus GG) or a prebiotic (oats) by gavage. Ileal and colonic mucosal-attached microbiota composition were interrogated by Length Heterogeneity PCR (LH-PCR) fingerprinting. Results:, Bacterial microbiota composition in alcohol-fed rats is not different from dextrose-fed rats at weeks 4 and 6. Mucosa-associated microbiota composition in the colon is altered at 10 weeks of daily alcohol gavage. Both LGG and oats prevented alcohol-induced dysbiosis up to 10 weeks of alcohol treatment. Conclusion:, Daily alcohol consumption for 10 weeks alters colonic mucosa-associated bacterial microbiota composition in rats. Our data showed, for the first time, that daily alcohol consumption can affect colonic microbiome composition and suggest that dysbiosis may be an important mechanism of alcohol-induced endotoxemia. Further studies are needed to determine how dysbiotic microbiota contributes to development of ALD and whether therapeutic interventions targeted towards dysbiotic microbiota can prevent complications of alcoholism like ALD. [source] Cardiopulmonary resuscitation after near drowning and hypothermia: restoration of spontaneous circulation after vasopressinACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2003G. Sumann Recent animal data have challenged the common clinical practice to avoid vasopressor drugs during hypothermic cardiopulmonary resuscitation (CPR) when core temperature is below 30°C. In this report, we describe the case of a 19-year-old-female patient with prolonged, hypothermic, out-of-hospital cardiopulmonary arrest after near drowning (core temperature, 27°C) in whom cardiocirculatory arrest persisted despite 2 mg of intravenous epinephrine; but, immediate return of spontaneous circulation occurred after a single dose (40 IU) of intravenous vasopressin. The patient was subsequently admitted to a hospital with stable haemodynamics, and was successfully rewarmed with convective rewarming, but died of multiorgan failure 15 h later. To the best of our knowledge, this is the first report about the use of vasopressin during hypothermic CPR in humans. This case report adds to the growing evidence that vasopressors may be useful to restore spontaneous circulation in hypothermic cardiac arrest patients prior to rewarming, thus avoiding prolonged mechanical CPR efforts, or usage of extracorporeal circulation. It may also support previous experience that the combination of both epinephrine and vasopressin may be necessary to achieve the vasopressor response needed for restoration of spontaneous circulation, especially after asphyxial cardiac arrest or during prolonged CPR efforts. [source] Evidence for shutter-speed variation in CR bolus-tracking studies of human pathologyNMR IN BIOMEDICINE, Issue 3 2005Thomas E. Yankeelov Abstract The standard pharmacokinetic model for the analysis of MRI contrast reagent (CR) bolus-tracking (B-T) data assumes that the mean intracellular water molecule lifetime (,i) is effectively zero. This assertion is inconsistent with a considerable body of physiological measurements. Furthermore, theory and simulation show the B-T time-course shape to be very sensitive to the ,i magnitude in the physiological range (hundreds of milliseconds to several seconds). Consequently, this standard model aspect can cause significant underestimations (factors of 2 or 3) of the two parameters usually determined: Ktrans, the vascular wall CR transfer rate constant, and ve, the CR distribution volume (the extracellular, extravascular space fraction). Analyses of animal model data confirmed two predicted behaviors indicative of this standard model inadequacy: (1) a specific temporal pattern for the mismatch between the best-fitted curve and data; and (2) an inverse dependence of the curve's Ktrans and ve magnitudes on the CR dose. These parameters should be CR dose-independent. The most parsimonious analysis allowing for realistic ,i values is the ,shutter-speed' model. Its application to the experimental animal data essentially eliminated the two standard model signature inadequacies. This paper reports the first survey for the extent of this ,shutter-speed effect' in human data. Retrospective analyses are made of clinical data chosen from a range of pathology (the active multiple sclerosis lesion, the invasive ductal carcinoma breast tumor, and osteosarcoma in the leg) that provides a wide variation, particularly of Ktrans. The signature temporal mismatch of the standard model is observed in all cases, and is essentially eliminated by use of the shutter-speed model. Pixel-by-pixel maps show that parameter values from the shutter-speed analysis are increased by more than a factor of 3 for some lesion regions. This endows the lesions with very high contrast, and reveals heterogeneities that are often not seen in the standard model maps. Normal muscle regions in the leg allow validation of the shutter-speed model Ktrans, ve, and ,i magnitudes, by comparison with results of previous careful rat leg studies not possible for human subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source] The acute hypoxic ventilatory response under halothane, isoflurane, and sevoflurane anaesthesia in rats,ANAESTHESIA, Issue 3 2010N. Karanovic Summary The relative order of potency of anaesthetic agents on the hypoxic ventilatory response has been tested in humans, but animal data are sparse. We examined the effects of 1.4, 1.6, 1.8, and 2.0 MAC halothane, isoflurane, and sevoflurane on phrenic nerve activity in euoxia (baseline) and during acute normocapnic hypoxia (inspired oxygen fraction 0.09) in adult male Sprague-Dawley rats. With halothane, all animals became apnoeic even in euoxia, and the hypoxic response was completely abolished at all anaesthetic levels. With isoflurane, 5 of 14 animals exhibited phrenic nerve activity in euoxia at 1.4 MAC and demonstrated a hypoxic response (302% of baseline activity), but all became apnoeic and lost the hypoxic response at higher doses. With sevoflurane, phrenic nerve activity and a hypoxic response was preserved in at least some animals at all doses (i.e. even the highest dose of 2.0 MAC). Similar to the rank order of potency previously observed in humans, the relative order of potency of depression of the hypoxic ventilatory response in rats was halothane (most depressive) > isoflurane > sevoflurane (p = 0.01 for differences between agents). [source] Reduced amygdala activity during aversive conditioning in human narcolepsyANNALS OF NEUROLOGY, Issue 3 2010Aurélie Ponz PhD Narcolepsy with cataplexy is a sleep-wake disorder caused by a loss of hypothalamic hypocretins. Here we assessed the time course of amygdala activation during aversive conditioning in unmedicated patients with narcolepsy. Unlike healthy matched control subjects, narcolepsy patients had no enhancement of amygdala response to conditioned stimuli and no increase in functional coupling between the amygdala and medial prefrontal cortex. These findings suggest that human narcolepsy is accompanied by abnormal emotional learning, and that, in line with animal data, the hypocretin system and the amygdala are involved in this process. ANN NEUROL 2010;67:394,398 [source] 1,026 Experimental treatments in acute strokeANNALS OF NEUROLOGY, Issue 3 2006Victoria E. O'Collins B.Sci Objective Preclinical evaluation of neuroprotectants fostered high expectations of clinical efficacy. When not matched, the question arises whether experiments are poor indicators of clinical outcome or whether the best drugs were not taken forward to clinical trial. Therefore, we endeavored to contrast experimental efficacy and scope of testing of drugs used clinically and those tested only experimentally. Methods We identified neuroprotectants and reports of experimental efficacy via a systematic search. Controlled in vivo and in vitro experiments using functional or histological end points were selected for analysis. Relationships between outcome, drug mechanism, scope of testing, and clinical trial status were assessed statistically. Results There was no evidence that drugs used clinically (114 drugs) were more effective experimentally than those tested only in animal models (912 drugs), for example, improvement in focal models averaged 31.3 ± 16.7% versus 24.4 ± 32.9%, p > 0.05, respectively. Scope of testing using Stroke Therapy Academic Industry Roundtable (STAIR) criteria was highly variable, and no relationship was found between mechanism and efficacy. Interpretation The results question whether the most efficacious drugs are being selected for stroke clinical trials. This may partially explain the slow progress in developing treatments. Greater rigor in the conduct, reporting, and analysis of animal data will improve the transition of scientific advances from bench to bedside. Ann Neurol 2006 [source] Incorporating Physiological and Biochemical Mechanisms into Pharmacokinetic,Pharmacodynamic Models: A Conceptual Framework,BASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2010Svein G. Dahl In general, modelling of data has the purpose (1) to describe experimental data, (2a) to reduce the amount of data resulting from an experiment, e.g. a clinical trial and (2b) to obtain the most relevant parameters, (3) to test hypotheses and (4) to make predictions within the boundaries of experimental conditions, e.g. range of doses tested (interpolation) and out of the boundaries of the experimental conditions, e.g. to extrapolate from animal data to the situation in man. Describing the drug/xenobiotic-target interaction and the chain of biological events following the interaction is the first step to build a biologically based model. This is an approach to represent the underlying biological mechanisms in qualitative and also quantitative terms, thus being inherently connected in many aspects to systems biology. As the systems biology models may contain variables in the order of hundreds connected with differential equations, it is obvious that it is in most cases not possible to assign values to the variables resulting from experimental data. Reduction techniques may be used to create a manageable model which, however, captures the biologically meaningful events in qualitative and quantitative terms. Until now, some success has been obtained by applying empirical pharmacokinetic/pharmacodynamic models which describe direct and indirect relationships between the xenobiotic molecule and the effect, including tolerance. Some of the models may have physiological components built in the structure of the model and use parameter estimates from published data. In recent years, some progress toward semi-mechanistic models has been made, examples being chemotherapy-induced myelosuppression and glucose-endogenous insulin-antidiabetic drug interactions. We see a way forward by employing approaches to bridge the gap between systems biology and physiologically based kinetic and dynamic models. To be useful for decision making, the ,bridging' model should have a well founded mechanistic basis, but being reduced to the extent that its parameters can be deduced from experimental data, however capturing the biological/clinical essential details so that meaningful predictions and extrapolations can be made. [source] Pharmacokinetic scaling of SJ-8029, a novel anticancer agent possessing microtubule and topoisomerase inhibiting activities, by species-invariant time methodsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 5 2003Beom S. Shin Abstract This study examined the pharmacokinetic disposition of SJ-8029, a novel anticancer agent possessing microtubule and topoisomerase inhibiting activities, in mice, rats, rabbits and dogs after i.v. administration. The serum concentration - time curves of SJ-8029 were best described by tri-exponential equations in all these animal species. The mean Cl, Vss and t1/2 were 0.3 l/h, 0.1 l and 63.2 min in mice, 1.5 l/h, 1.6 l and 247.7 min in rats, 13.8 l/h, 39.6 l and 245.9 min in rabbits, and 29.2 l/h, 44.6 l and 117.4 min in dogs, respectively. Based on animal data, the pharmacokinetics of SJ-8029 were predicted in humans using simple allometry and also by several species-invariant time transformations using kallynochron, apolysichron and dienetichron times. The human pharmacokinetic parameters of Cl, Vss and t1/2 predicted by the simple allometry and various species-invariant time methods were 50.4,145.0 l/h, 369.0,579.8 l and 242.0,1448.3 min, respectively. These preliminary parameter values may be useful in designing early pharmacokinetic studies of SJ-8029 in humans. Copyright © 2003 John Wiley & Sons, Ltd. [source] Nutrient intakes in women and congenital diaphragmatic hernia in their offspring,BIRTH DEFECTS RESEARCH, Issue 3 2008Wei Yang Abstract BACKGROUND: Congenital diaphragmatic hernia (CDH) is a severe birth defect where there is an opening in the diaphragm through which a portion of the abdominal contents protrudes into the thoracic cavity. The etiologies of CDH remain unknown, although experimental animal data suggest dietary factors might play a role. This study examined whether maternal nutrient intakes were associated with delivering infants with CDH. METHODS: We analyzed infants with isolated CDH who were born from 1997 to 2003 and recruited into the National Birth Defects Prevention Study (NBDPS), a multisite, population-based case-control study. Exposure data were obtained from telephone interviews, which were completed within 24 months after delivery, and were available for 377 case mothers and 5,008 control mothers. A food frequency questionnaire was used to derive nutrient intakes during the year before pregnancy. RESULTS: A crude OR of 0.6 (95% CI: 0.3,1.0) was observed for higher intake of choline. Elevated ORs (1.4 to 1.7) were found for lower intakes of choline, cysteine, methionine, and protein. Among women who took vitamin supplements, higher intakes of B vitamins (i.e., folate, vitamin B1, B2, B6, and B12), minerals (i.e., calcium, iron, magnesium, and zinc), and vitamin E were inversely associated with CDH (ORs from 0.7,0.3). Moreover, among women who did not take vitamin supplements, lower intakes of calcium, retinol, selenium, vitamin B12, and vitamin E had positive associations with CDH (ORs from 1.4 to 2.1). CONCLUSIONS: Our observations contribute to a limited body of evidence suggesting a woman's periconceptional diet might be associated with CDH in her offspring. Birth Defects Research (Part A), 2008. © 2007 Wiley-Liss, Inc. [source] Interleukin 13 and inflammatory markers in human sepsis,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 6 2004N. Collighan Background: Interleukin (IL) 13 is an anti-inflammatory cytokine that reduces inflammatory cytokine production, and enhances monocyte survival and MHC class II and CD23 expression. The only report of IL-13 in human sepsis noted no increase in IL-13 concentration, in contrast to animal data. This study further examined the expression of IL-13 in relation to human sepsis. Methods: In a prospective observational study of 31 patients (24 men) with sepsis or septic shock, high-sensitivity enzyme-linked immunoabsorbent assay (ELISA) was used to quantify levels of tumour necrosis factor (TNF) , on admission, and on days 1, 3, 5 and 7 thereafter. IL-13 and IL-2 were assayed by standard ELISA, and HLA-DR on CD14-positive monocytes was measured by flow cytometry. Results: Twenty-three patients developed septic shock. Monocyte HLA-DR levels showed greater depression and a slower recovery in shocked than non-shocked patients. The serum IL-13 concentration was significantly higher in the shocked group from admission to day 3, but subsequently decreased to levels similar to those in the non-shocked group. IL-13 concentrations were higher in non-survivors. The TNF-, concentration was higher in those with septic shock than in those without. The TNF-, level correlated with IL-13 concentration (rS = 0·61, P = 0·002). The IL-13/TNF-, ratio was greater in patients with shock than those with sepsis only (P = 0·017). IL-2 was undetectable. Conclusion: In human sepsis and septic shock, IL-13 correlated with TNF-, expression, but its effect on HLA-DR class II molecules remains unclear. Copyright © 2004 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] 2165: Microplasmin as an antiscarring agent for glaucoma surgery: translation into clinical applicationACTA OPHTHALMOLOGICA, Issue 2010E VANDEWALLEArticle first published online: 23 SEP 2010 Purpose Previously Microplasmin was investigated in a rabbit model for trabeculectomy. The combination of intracameral injections and topical drops of Microplasmin improved surgical outcome. The aqueous solution of Microplasmin used, was not optimized for use as drops or injections. Microplasmin is an autocatalytic enzyme which has a short half life when it is brought in conditions of 37°C and physiological pH. Therefore there is need for a more stable and longer acting formulation. Methods Firstly we will do pharmacological experiments to determine the rheological characterization of drug carriers with Carrier-med rheometer. Then we will define the purity of Microplasmin bulk drug substance by RP-HPLC. Finally, we will check the Microplasmin activity in the new obtained solutions by spectrophotometer. Secondly we will perform trabeculectomy in a rabbit model and administer the most qualified and optimized formulations. Postoperative clinical evaluation of IOP, bleb area, conjunctival vascularity and anterior chamber assessment will be performed. The eyes will be immunohistological investigated for collagen and inflammation. Conclusion Our previous data learned that the combination therapy of Microplasmin improved surgical outcome in a rabbit model, despite the fact that the formulation of Microplasmin was not optimized for use as drops or injections. Our proposed research project will optimize the formulation of Microplasmin for extended drug delivery and determine the optimal administration route and regimen. We believe that this project will allow us to further improve the positive animal data, translate this novel antifibrotic adjunctive therapy into clinical application, and thus improve the outcome after trabeculectomy in patients. [source] | ||||||||||||||||||||||