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1.
Anim Genet ; 51(1): 137-140, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31729778

ABSTRACT

Black and tan animals have tan-coloured ventral body surfaces separated by sharp boundaries from black-coloured dorsal body surfaces. In the at mouse mutant, a retroviral 6 kb insertion located in the hair cycle-specific promoter of the murine Asip gene encoding agouti signalling protein causes the black and tan phenotype. In rabbits, three ASIP alleles are thought to exist, including an at allele causing a black and tan coat colour that closely resembles the mouse black and tan phenotype. The goal of our study was to identify the functional genetic variant causing the rabbit at allele. We performed a WGS-based comparative analysis of the ASIP gene in one black and tan and three wt agouti-coloured rabbits. The analysis identified 75 at -associated variants including an 11 kb deletion. The deletion is located in the region of the hair cycle-specific ASIP promoter and thus in a region homologous to the site of the retroviral insertion causing the at allele in mice. We observed perfect association of the genotypes at this deletion with the coat colour phenotype in 49 rabbits. The comparative analysis and the previous knowledge about the regulation of ASIP expression suggest that the 11 kb deletion is the most likely causative variant for the black and tan phenotype in rabbits.


Subject(s)
Agouti Signaling Protein/genetics , Exons , Hair Color/genetics , Promoter Regions, Genetic , Rabbits/genetics , Sequence Deletion , Alleles , Animals , Phenotype
2.
Anim Genet ; 50(6): 761-763, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31463981

ABSTRACT

White spotting phenotypes in horses may be caused by developmental alterations impairing melanoblast differentiation, survival, migration and/or proliferation. Candidate genes for white-spotting phenotypes in horses include EDNRB, KIT, MITF, PAX3 and TRPM1. We investigated a German Riding Pony with a sabino-like phenotype involving extensive white spots on the body together with large white markings on the head and almost completely white legs. We obtained whole genome sequence data from this horse. The analysis revealed a heterozygous 1273-bp deletion spanning parts of intron 2 and exon 3 of the equine KIT gene (Chr3: 79 579 925-79 581 197). We confirmed the breakpoints of the deletion by PCR and Sanger sequencing. Knowledge of the functional impact of similar KIT variants in horses and other species suggests that this deletion represents a plausible candidate causative variant for the white-spotting phenotype. We propose the designation W28 for the mutant allele.


Subject(s)
Hair Color , Horses/genetics , Stem Cell Factor/genetics , Animals , Exons
3.
Anim Genet ; 50(2): 172-174, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30644113

ABSTRACT

White spotting phenotypes in horses are highly valued in some breeds. They are quite variable and may range from the common white markings up to completely white horses. EDNRB, KIT, MITF, PAX3 and TRPM1 represent known candidate genes for white spotting phenotypes in horses. For the present study, we investigated an American Paint Horse family segregating a phenotype involving white spotting and blue eyes. Six of eight horses with the white-spotting phenotype were deaf. We obtained whole-genome sequence data from an affected horse and specifically searched for structural variants in the known candidate genes. This analysis revealed a heterozygous ~63-kb deletion spanning exons 6-9 of the MITF gene (chr16:21 503 211-21 566 617). We confirmed the breakpoints of the deletion by PCR and Sanger sequencing. PCR-based genotyping revealed that all eight available affected horses from the family carried the deletion. The finding of an MITF variant fits well with the syndromic phenotype involving both depigmentation and an increased risk for deafness and corresponds to human Waardenburg syndrome type 2A. Our findings will enable more precise genetic testing for depigmentation phenotypes in horses.


Subject(s)
Deafness/veterinary , Gene Deletion , Horse Diseases/genetics , Horses/genetics , Microphthalmia-Associated Transcription Factor/genetics , Animals , Color , Deafness/genetics , Female , Male , Microphthalmia-Associated Transcription Factor/metabolism , Pigmentation/genetics , Risk Factors , Whole Genome Sequencing/veterinary
4.
ISME J ; 16(6): 1523-1533, 2022 06.
Article in English | MEDLINE | ID: mdl-35124702

ABSTRACT

The reduction of manganese oxide with sulfide in aquatic redox-stratified systems was previously considered to be mainly chemical, but recent isolation of the Black Sea isolate Candidatus Sulfurimonas marisnigri strain SoZ1 suggests an important role for biological catalyzation. Here we provide evidence from laboratory experiments, field data, and modeling that the latter process has a strong impact on redox zonation in the Black Sea. High relative abundances of Sulfurimonas spp. across the redoxcline in the central western gyre of the Black Sea coincided with the high-level expression of both the sulfide:quinone oxidoreductase gene (sqr, up to 93% expressed by Sulfurimonas spp.) and other sulfur oxidation genes. The cell-specific rate of manganese-coupled sulfide oxidation by Ca. S. marisnigri SoZ1 determined experimentally was combined with the in situ abundance of Sulfurimonas spp. in a one-dimensional numerical model to calculate the vertical sulfide distribution. Abiotic sulfide oxidation was too slow to counterbalance the sulfide flux from euxinic water. We conclude that microbially catalyzed Mn-dependent sulfide oxidation influences the element cycles of Mn, S, C, and N and therefore the prevalence of other functional groups of prokaryotes (e.g., anammox bacteria) in a sulfide-free, anoxic redox zone.


Subject(s)
Manganese , Water , Black Sea , Oxidation-Reduction , Seawater/microbiology , Sulfides/metabolism
5.
Acta Myol ; 30(1): 4-8, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21842586

ABSTRACT

Neuroinflammation is a pathological hallmark of neurodegenerative diseases including amyotrophic lateral sclerosis (ALS), and is characterized by activated microglia at sites of neuronal injury. In ALS, neurons do not die alone; neuronal injury is noncell-autonomous and depends upon a well-orchestrated dialogue between motor neurons and microglia. Evidence from transgenic models expressing mutant superoxide dismutase 1 (SOD) suggests that the dialogue between motor neurons and microglia initially protects motor neurons. However, with increasing stress and injury within motor neurons, induced by the presence of misfolded proteins such as mSOD1, mitochondrial function and axoplasmic flow are impaired and endoplasmic reticulum stress is induced; misfolded proteins themselves or alternate signals are released from motor neurons and activate microglia. Activated microglia, in turn, switch from anti-inflammatory and neuroprotective to proinflammatory and neurotoxic. Neurotoxic signaling from motor neurons promotes microglial release of reactive oxygen species and pro-inflammatory cytokines further enhancing motor neuron stress and cell injury and initiating a self-propagating cycle of motor neuron injury and cell death. A greater understanding of how to restore the imbalance between neuroprotection and cytotoxicity will depend upon a greater understanding of the motor neuron-microglial dialogue.


Subject(s)
Amyotrophic Lateral Sclerosis/physiopathology , Microglia/physiology , Motor Neurons/physiology , Animals , Cell Communication , Cell Death , Endoplasmic Reticulum/physiology , Humans , Inflammation Mediators/metabolism , Mitochondria, Muscle/physiology , Protein Folding , Reactive Oxygen Species/metabolism , Signal Transduction , Superoxide Dismutase/physiology , Superoxide Dismutase-1
6.
Water Sci Technol ; 63(12): 3034-8, 2011.
Article in English | MEDLINE | ID: mdl-22049735

ABSTRACT

The alpha-factor has the greatest impact on the calculation of the required standard oxygen transfer rate (SOTR) in activated sludge systems equipped with submerged aeration systems. Knowing the dependencies of the alpha-factor leads to a better design of the aeration devices and, consequently, to a more efficient use of aeration energy. Applying the current state of knowledge about oxygen transfer leads to the conclusion that, in contrast to current opinion, simultaneous aerobic stabilization requires the same SOTR as conventional activated sludge systems with advanced nutrient removal, even though a higher organic load is degraded.


Subject(s)
Cost Savings , Models, Theoretical , Oxygen/chemistry , Sewage/chemistry , Water Purification/economics , Water Purification/methods , Aerobiosis , Biological Oxygen Demand Analysis , Sewage/microbiology , Time Factors , Viscosity
7.
Int J Qual Health Care ; 22(6): 486-92, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20956283

ABSTRACT

OBJECTIVE: The increasing prevalence of obesity requires particularly primary care providers to take action. The aim of this study was to analyze general practitioners (GPs) encounters with overweight and obese patients in primary care to test the hypothesis that patients with a BMI ≥ 30 kg/m² would have longer consultations focusing on lifestyle-related issues like nutrition and physical activity than those with a BMI < 30 kg/m². DESIGN: Cross sectional comparison of audiotaped encounters of patients with a BMI ≥ 30 kg/m² and those with a BMI < 30 kg/m². SETTING: Twelve GP surgeries in Berlin, Germany. PARTICIPANTS: Fifty patients who agreed to have preventive check-up encounters audiotaped. MAIN OUTCOME MEASURES: Based on the Roter Interaction ANALYSIS: System (RIAS) we assessed duration of encounter and the prevalence of GP statements regarding cardiovascular risks, nutrition and physical activity. RESULTS: An increased BMI was found to be a predictor for the length of encounters (P = 0.01), whereas the content of talks was mainly determined by the individual of GP and sex of the GP. Statements regarding cardiovascular risks were most frequent, followed by those regarding nutrition and physical activity. In this study the assessed physiological parameters were not associated with the specific contents of preventive encounters like nutrition or physical activity (P > 0.05). CONCLUSIONS: Our results indicate that GPs rarely use the check-up program to conduct lifestyle consultations with obese patients. Barriers to lifestyle counseling and possible solutions are discussed with a view to promoting individualized and target management of overweight patients.


Subject(s)
Counseling/statistics & numerical data , Health Behavior , Obesity/prevention & control , Overweight/therapy , Primary Health Care/methods , Adult , Berlin , Body Mass Index , Cardiovascular Diseases/etiology , Cardiovascular Diseases/prevention & control , Counseling/methods , Cross-Sectional Studies , Female , Guideline Adherence , Humans , Male , Middle Aged , Motor Activity , Nutritional Sciences/education , Obesity/complications , Obesity/therapy , Office Visits/statistics & numerical data , Overweight/complications , Overweight/prevention & control , Primary Health Care/standards , Risk Factors , Sex Factors
8.
Rozhl Chir ; 89(3): 188-93, 2010 Mar.
Article in Czech | MEDLINE | ID: mdl-20514915

ABSTRACT

AIM: The evaluation of the contribution of Free Hand camera to laparoscopic resection of colon sigmoideum in clinical praxis. MATERIAL AND METHOD: Free Hand camera is an automatic camera system controlled by a surgeon. In the prospective-retrospective trial we have compared two groups of 20 patients together. In the first group there were patients with laparoscopic resection of colon sigmoideum with the Free hand camera usage and in the second group there were patients with laparoscopic resection of colon sigmoideum with a human assistant. We evaluated the length of surgery and surgeon's comfort. The intraoperative data of both of the patient groups were compared with the usage of physiological and operative score (POSSUM). RESULTS: The length of surgery in the group with the human assistant and Free Hand camera were 149, and 161 minutes respectively. There is no statistically significant difference in the length of surgery (p = 0.05) in both of the groups. The surgeon in both of the patient groups evaluated the operative view and comfort as good. CONCLUSION: The pilot study has shown the usability of Free Hand in praxis. The daily usage of Free Hand camera is possible in elective as well as acute surgeries after managing of the learning curve.


Subject(s)
Colon, Sigmoid/surgery , Laparoscopy , Video-Assisted Surgery/instrumentation , Female , Humans , Male , Middle Aged , Robotics
9.
Biomaterials ; 247: 119998, 2020 07.
Article in English | MEDLINE | ID: mdl-32251928

ABSTRACT

Many skeletal tissue regenerative strategies centre around the multifunctional properties of bone marrow derived stromal cells (BMSC) or mesenchymal stem/stromal cells (MSC)/bone marrow derived skeletal stem cells (SSC). Specific identification of these particular stem cells has been inconclusive. However, enriching these heterogeneous bone marrow cell populations with characterised skeletal progenitor markers has been a contributing factor in successful skeletal bone regeneration and repair strategies. In the current studies we have isolated, characterised and enriched ovine bone marrow mesenchymal stromal cells (oBMSCs) using a specific antibody, Stro-4, examined their multipotential differentiation capacity and, in translational studies combined Stro-4+ oBMSCs with a bovine extracellular matrix (bECM) hydrogel and a biocompatible melt electro-written medical-grade polycaprolactone scaffold, and tested their bone regenerative capacity in a small in vivo, highly vascularised, chick chorioallantoic membrane (CAM) model and a preclinical, critical-sized ovine segmental tibial defect model. Proliferation rates and CFU-F formation were similar between unselected and Stro-4+ oBMSCs. Col1A1, Col2A1, mSOX-9, PPARG gene expression were upregulated in respective osteogenic, chondrogenic and adipogenic culture conditions compared to basal conditions with no significant difference between Stro-4+ and unselected oBMSCs. In contrast, proteoglycan expression, alkaline phosphatase activity and adipogenesis were significantly upregulated in the Stro-4+ cells. Furthermore, with extended cultures, the oBMSCs had a predisposition to maintain a strong chondrogenic phenotype. In the CAM model Stro-4+ oBMSCs/bECM hydrogel was able to induce bone formation at a femur fracture site compared to bECM hydrogel and control blank defect alone. Translational studies in a critical-sized ovine tibial defect showed autograft samples contained significantly more bone, (4250.63 mm3, SD = 1485.57) than blank (1045.29 mm3, SD = 219.68) ECM-hydrogel (1152.58 mm3, SD = 191.95) and Stro-4+/ECM-hydrogel (1127.95 mm3, SD = 166.44) groups. Stro-4+ oBMSCs demonstrated a potential to aid bone repair in vitro and in a small in vivo bone defect model using select scaffolds. However, critically, translation to a large related preclinical model demonstrated the complexities of bringing small scale reported stem-cell material therapies to a clinically relevant model and thus facilitate progression to the clinic.


Subject(s)
Mesenchymal Stem Cells , Animals , Bone Marrow , Bone Marrow Cells , Cattle , Cell Differentiation , Cells, Cultured , Extracellular Matrix , Hydrogels , Osteogenesis , Polyesters , Sheep
10.
J Cell Biol ; 148(3): 495-504, 2000 Feb 07.
Article in English | MEDLINE | ID: mdl-10662775

ABSTRACT

The function of acidification in protein sorting along the biosynthetic pathway has been difficult to elucidate, in part because reagents used to alter organelle pH affect all acidified compartments and are poorly reversible. We have used a novel approach to examine the role of acidification in protein sorting in polarized Madin-Darby canine kidney (MDCK) cells. We expressed the influenza virus M2 protein, an acid-activated ion channel that equilibrates lumenal and cytosolic pH, in polarized MDCK cells and examined the consequences on the targeting and delivery of apical and basolateral proteins. M2 activity affects the pH of only a subset of acidified organelles, and its activity can be rapidly reversed using ion channel blockers (Henkel, J.R., G. Apodaca, Y. Altschuler, S. Hardy, and O.A. Weisz. 1998. Mol. Biol. Cell. 8:2477-2490; Henkel, J.R., J.L. Popovich, G.A. Gibson, S.C. Watkins, and O.A. Weisz. 1999. J. Biol. Chem. 274:9854-9860). M2 expression significantly decreased the kinetics of cell surface delivery of the apical membrane protein influenza hemagglutinin, but not of the basolaterally delivered polymeric immunoglobulin receptor. Similarly, the kinetics of apical secretion of a soluble form of gamma-glutamyltranspeptidase were reduced with no effect on the basolaterally secreted fraction. Interestingly, M2 activity had no effect on the rate of secretion of a nonglycosylated protein (human growth hormone [hGH]) that was secreted equally from both surfaces. However, M2 slowed apical secretion of a glycosylated mutant of hGH that was secreted predominantly apically. Our results suggest a role for acidic trans-Golgi network pH in signal-mediated loading of apical cargo into forming vesicles.


Subject(s)
Golgi Apparatus/metabolism , Influenza A virus/metabolism , Ion Channels/metabolism , Viral Matrix Proteins/metabolism , Animals , Cell Line , Cell Membrane/metabolism , Cell Polarity , Dogs , Gene Expression , Hemagglutinin Glycoproteins, Influenza Virus/biosynthesis , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Humans , Protons , Receptors, Polymeric Immunoglobulin/biosynthesis , Receptors, Polymeric Immunoglobulin/genetics , Viral Matrix Proteins/genetics
11.
Mol Biol Cell ; 9(9): 2477-90, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9725907

ABSTRACT

The function of acidification along the endocytic pathway is not well understood, in part because the perturbants used to modify compartmental pH have global effects and in some cases alter cytoplasmic pH. We have used a new approach to study the effect of pH perturbation on postendocytic traffic in polarized Madin-Darby canine kidney (MDCK) cells. Influenza M2 is a small membrane protein that functions as an acid-activated ion channel and can elevate the pH of the trans-Golgi network and endosomes. We used recombinant adenoviruses to express the M2 protein of influenza virus in polarized MDCK cells stably transfected with the polymeric immunoglobulin (Ig) receptor. Using indirect immunofluorescence and immunoelectron microscopy, M2 was found to be concentrated at the apical plasma membrane and in subapical vesicles; intracellular M2 colocalized partly with internalized IgA in apical recycling endosomes as well as with the trans-Golgi network marker TGN-38. Expression of M2 slowed the rate of IgA transcytosis across polarized MDCK monolayers. The delay in transport occurred after IgA reached the apical recycling endosome, consistent with the localization of intracellular M2. Apical recycling of IgA was also slowed in the presence of M2, whereas basolateral recycling of transferrin and degradation of IgA were unaffected. By contrast, ammonium chloride affected both apical IgA and basolateral transferrin release. Together, our data suggest that M2 expression selectively perturbs acidification in compartments involved in apical delivery without disrupting other postendocytic transport steps.


Subject(s)
Ion Channels/metabolism , Orthomyxoviridae/metabolism , Viral Matrix Proteins/metabolism , Animals , Biological Transport , Cell Line , Cell Membrane/metabolism , Cell Polarity , Dogs , Gene Expression , Hydrogen-Ion Concentration , Immunoglobulin A/metabolism , Ion Channels/genetics , Viral Matrix Proteins/genetics
12.
J Tissue Eng Regen Med ; 11(7): 2081-2089, 2017 07.
Article in English | MEDLINE | ID: mdl-26648044

ABSTRACT

The properties of osteoblasts (OBs) isolated from the axial skeleton (tOBs) differ from OBs of the orofacial skeleton (mOBs) due to the different embryological origins of the bones. The aim of the study was to assess and compare the regenerative potential of allogenic bone marrow-derived mesenchymal progenitor cells with allogenic tOBs and allogenic mOBs in combination with a mPCL-TCP scaffold in critical-sized segmental bone defects in sheep tibiae. After 6 months, the tibiae were explanted and underwent biomechanical testing, micro-computed tomography (microCT) and histological and immunohistochemical analyses. Allogenic MPCs demonstrated a trend towards a better outcome in biomechanical testing and the mean values of newly formed bone. Biomechanical, microCT and histological analysis showed no significant differences in the bone regeneration potential of tOBs and mOBs in our in vitro study, as well as in the bone regeneration potential of different cell types in vivo. Copyright © 2015 John Wiley & Sons, Ltd.


Subject(s)
Bone Regeneration , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Osteoblasts , Tibia/injuries , Tibia/metabolism , Tissue Scaffolds , Allografts , Animals , Osteoblasts/metabolism , Osteoblasts/transplantation , Osteogenesis , Sheep , Tibia/diagnostic imaging , Tissue Engineering/methods , X-Ray Microtomography
13.
Biochim Biophys Acta ; 614(2): 564-76, 1980 Aug 07.
Article in English | MEDLINE | ID: mdl-6250629

ABSTRACT

Ribulose-1,5-bisphosphate carboxylase-oxygenase (3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39) is deactivated by the removal of oxygen, and reversibly reactivated by its readdition to the enzyme solution. A short pulse of oxygen to the anaerobic enzyme solution is sufficient to trigger the reactivation process; the Ka value for this reaction was estimated as 0.12 mM oxygen. The enzyme could not be reactivated under anaerobic conditions by an organic oxidant (benzoylperoxide) or by sulfhydryl group reducing reagents (dithiothreitol or beta-mercaptoethanol), suggesting that the process of reactivation was oxygen specific. Furthermore, the inhibition of the reactivation by superoxide anion scavengers such as Tiron (1,2-dihydroxybenzene-3,5-disulfonic acid), copper penicillamine, hydroxylamine, nitroblue tetrazolium, and ascorbate, indicated that the monovalent reduced oxygen was involved as the reacting species in this process. The deactivation of the enzyme associated with the removal of oxygen was also sensitive to the presence of scavengers of O2(-), suggesting that superoxide anion was also involved in the deactivation process. Both the carboxylase and the oxygenase activities were similarly affected under all the experimental conditions studied. On the basis of these results it is argued that the enzyme molecules are able to reduce oxygen and that superoxide anion causes the deactivation or reactivation of the enzyme.


Subject(s)
Carboxy-Lyases/metabolism , Oxygen/pharmacology , Plants/enzymology , Ribulose-Bisphosphate Carboxylase/metabolism , 1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt/pharmacology , Benzoyl Peroxide/pharmacology , Dithiothreitol/pharmacology , Enzyme Activation/drug effects , Kinetics , Mercaptoethanol/pharmacology , Superoxides/pharmacology
14.
J Neuropathol Exp Neurol ; 52(3): 241-52, 1993 May.
Article in English | MEDLINE | ID: mdl-8388040

ABSTRACT

Herpes simplex virus type 1 (HSV-1) is the cause of a serious and often fatal encephalitis. Patients who survive herpes simplex encephalitis (HSE) experience behavioral abnormalities including profound cognitive dysfunctions. We have developed a rat model of acute HSE to investigate the cognitive impairments caused by HSV-1 central nervous system (CNS) infection. Following intranasal inoculation of Lewis rats with a neurovirulent strain of HSV-1, animals shed virus in both ocular and nasal secretions and developed clinical signs of infection, including partial complex motor seizures that eventually generalized. Homogenization assays demonstrated infectious virus in the trigeminal ganglia, olfactory bulbs, and the piriform and entorhinal cortices. Histopathological assessment revealed inflammatory and hemorrhagic lesions in the trigeminal ganglia, olfactory bulbs, amygdala, hippocampus, the piriform and entorhinal cortices, and the spinal trigeminal nuclei. Viral antigens and nucleic acids were also detected within these structures by immunofluorescence microscopy and in situ hybridization, respectively. Viral-induced astrocytic hypertrophy in the CNS was demonstrated by glial fibrillary acidic protein immunoreactivity. Together, these results indicate that HSV-1 has the ability to invade, replicate, and induce site-specific CNS damage in the Lewis rat.


Subject(s)
Encephalitis/microbiology , Rats, Inbred Lew/microbiology , Simplexvirus , Animals , Antigens, Viral/analysis , Cerebral Cortex/microbiology , DNA, Viral/analysis , Disease Models, Animal , Encephalitis/genetics , Encephalitis/immunology , Encephalitis/pathology , Female , In Situ Hybridization , Olfactory Bulb/microbiology , RNA, Viral/analysis , Rats , Simplexvirus/genetics , Simplexvirus/immunology , Simplexvirus/isolation & purification , Trigeminal Ganglion/microbiology
15.
Neurology ; 42(9): 1809-12, 1992 Sep.
Article in English | MEDLINE | ID: mdl-1325041

ABSTRACT

An atypical form of herpes simplex encephalitis produced by HSV-1 documented in the present article demonstrates that (1) prominent EEG abnormality may correlate with subtle increase in signal intensity on MRI; (2) the disease may start with prominent involvement of the cingulate gyri; and (3) viral infection of the brainstem may cause early onset of severe neurologic dysfunction and coma.


Subject(s)
Encephalitis/diagnosis , Encephalitis/microbiology , Herpes Simplex/diagnosis , Brain Stem/microbiology , Brain Stem/pathology , Electroencephalography , Encephalitis/pathology , Female , Gyrus Cinguli/microbiology , Gyrus Cinguli/pathology , Humans , Magnetic Resonance Imaging , Middle Aged , Nucleic Acid Hybridization , Simplexvirus/genetics , Simplexvirus/isolation & purification
16.
J Med Chem ; 25(1): 51-6, 1982 Jan.
Article in English | MEDLINE | ID: mdl-7086822

ABSTRACT

A limited series of bridgehead alkyl-, dialkyl-, and trialkyl-substituted amantadines was synthesized and tested for potential anti-Parkinson activity as dopamine (DA) agonists. The compounds were evaluated using a battery of three murine bioassays, including stimulation of locomotor activity, induction of circling in animals with unilateral striatal lesions, and reversal of reserpine/alpha-methyltyrosine induced akinesia. Apparent mechanistic differences were seen between the methyl-substituted series and the ethyl-substituted series. While activities in both series increase with increasing liphophilicity, the methyl series (1b--d), as well as amantadine itself (1a), exhibit only indirect DA agonist activity, as evidenced by ipsilateral rotation in the circling model and no significant difference from control in reversal of akinesia. The ethyl series (1e,f) exhibits weak but reproducible direct DA agonist activity, as shown by contralateral rotation in the circling assay for 1e and reversal of akinesia by 1e and 1f. The 3-n-propyl derivative (1g) was devoid of any DA agonist activity.


Subject(s)
Amantadine/analogs & derivatives , Antiparkinson Agents/pharmacology , Amantadine/chemical synthesis , Amantadine/pharmacology , Animals , Antiparkinson Agents/chemical synthesis , Mice , Motor Activity/drug effects , Receptors, Dopamine/drug effects , Structure-Activity Relationship
17.
J Med Chem ; 19(1): 6-10, 1976 Jan.
Article in English | MEDLINE | ID: mdl-1536

ABSTRACT

Crystalline perchlorate salts of aziridinium ions derived from phenoxybenzamine and dibenamine were prepared. Both aziridinium ions were tested on the rat vas deferens and found to possess alpha-adrenergic potencies which were nearly identical with those of the parent compounds. The hydrolysis rates of phenoxybenzamine and dibenamine aziridinium ions (2a,b) in physiological medium were found to be 6.0 4 x 10(-4) and 8.35 x 10(-4) sec-1, respectively. The rates of cyclization of the parent amines to 2a and 2b in aqueous medium were 1.9 x 10(-2) and 7.2 x 10(-3) sec-1, respectively. The potencies and kinetic profiles indicate that the aziridinium ion is the only active species in alpha-adrenergic blockade. Moreover, differences in potency between phenoxybenzamine and dibenamine appear to be exclusively to a difference in receptor affinity rather than to a difference in intrinsic alkylating ability.


Subject(s)
Adrenergic alpha-Antagonists/chemical synthesis , Aziridines/chemical synthesis , Azirines/chemical synthesis , Dibenzylchlorethamine/analogs & derivatives , Phenoxybenzamine/analogs & derivatives , Animals , Aziridines/pharmacology , Cyclization , Dibenzylchlorethamine/chemical synthesis , Dibenzylchlorethamine/pharmacology , Hydrolysis , Kinetics , Male , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Phenoxybenzamine/chemical synthesis , Phenoxybenzamine/pharmacology , Rats , Vas Deferens/drug effects
18.
J Med Chem ; 19(11): 1308-14, 1976 Nov.
Article in English | MEDLINE | ID: mdl-1003408

ABSTRACT

The synthesis of racemic threo- and erythro-5-methylmethadone (3a and 3b, respectively) was carried out and the solution conformation of each isomer was investigated through pKa and NMR studies. The data indicate that 3a-HCl exists exclusively in an internally hydrogen-bonded conformation while the erythro isomer 3b-HCl is present as a mixture of conformations. The erythro racemate 3b was found to possess 5.4 times the analgetic potency of (+/-)-methadone in contrast to the threo racemate 3a which was inactive and devoid of antagonist activity. The fact that the inactive racemate 3a contains the 5S,6R stereoisomer, which combines the configurations found in the more active enantiomers of methadone and isomethadone, suggests that the chiral centers do not behave as independent units and that conformational factors are playing an important role in governing stereoselectivity. These results, when analyzed together with earlier reports, suggest that one of the pharmacophoric conformations of the diphenylpropylamine analgetics possesses an antiperiplanar-like disposition of the Ph2CCOEt and +NHMe2 groups.


Subject(s)
Analgesics/chemical synthesis , Methadone/analogs & derivatives , Animals , Drug Antagonism , Magnetic Resonance Spectroscopy , Male , Methadone/chemical synthesis , Methadone/pharmacology , Mice , Models, Structural , Molecular Conformation , Naloxone/pharmacology , Stereoisomerism , Structure-Activity Relationship
19.
J Med Chem ; 24(10): 1258-60, 1981 Oct.
Article in English | MEDLINE | ID: mdl-7328588

ABSTRACT

In order to assess the potential for sympathomimetic or sympatholytic activity within the series of catecholamine beta-sulfonates 3a-c, alpha- and beta-adrenoceptor binding affinities were determined using rat brain homogenate preparations. Furthermore, their potential for indirect activity was assessed by measurement of blockade of norepinephrine uptake into rat synaptosomal preparations. Activity was uniformly low or nonexistent throughout the series. The possibility of unfavorable solution conformational distribution within the series was investigated by examination of the side chain vicinal 1H NMR coupling constants, but no differences that could account for the lack of affinity were found. The observed behavior may be due to receptor intolerance of the bulky beta-sulfonate substituent or an electronic mismatch in which normal H bonding is significantly altered.


Subject(s)
Catecholamines/metabolism , Receptors, Adrenergic/metabolism , Animals , Brain/metabolism , Catecholamines/chemical synthesis , Catecholamines/pharmacology , Hydrogen Bonding , In Vitro Techniques , Molecular Conformation , Rats , Receptors, Adrenergic/drug effects , Stereoisomerism , Structure-Activity Relationship
20.
Virus Res ; 50(1): 95-106, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9255939

ABSTRACT

We have analyzed the activity of a specific portion of the latency-associated transcript (LAT) promoter of three strains of herpes simplex virus type 1 (HSV-1) in neuronal and non-neuronal cell types. Restriction fragments containing the LAT promoter sequences and the 5'-end of the LATs were isolated from HSV-1 strains H129, +GC and KOS-63, sequenced and cloned into a chloramphenicol transferase (CAT) plasmid vector. These vectors were separately assayed for CAT production in human (SknSH) and mouse (C-1300) neuroblastoma cell lines and a human continuous cell line (HeLa). Strain KOS-63 contained a C to T base substitution within the LAT promoter binding factor element upstream of the cAMP response element binding sequence. In replicate experiments, in which the construct DNA was used for transfection, the CAT constructs from strains H129 and +GC functioned equally well in all three cell lines. In contrast, the strain KOS-63 CAT construct functioned significantly better in HeLa cells than in neuroblastoma cell lines and better than the identical CAT constructs from strains H129 and +GC. In addition, the construct from strain KOS-63 functioned less well in the human neuroblastoma cell line than in HeLa or C-1300 neuroblastoma cells. When LAT expression was examined directly in vivo by in situ hybridization, strain KOS-63 produced slightly less LAT RNA than strain H129 within trigeminal ganglionic neurons of latently infected rabbits. However, utilizing competitive gel-shift assays, DNA fragments containing the LAT promoter binding element from all three strains bound equivalent amounts of HeLa cell nuclear proteins. Together, these results suggest that the activity expressed by the strain KOS-63 LAT promoter in vivo and in vitro may relate to positive or negative effects of DNA binding proteins on LAT transcription, and that these effects are cell-type dependent.


Subject(s)
Herpesvirus 1, Human/genetics , Promoter Regions, Genetic , Transcription, Genetic , Virus Latency/genetics , Animals , Base Sequence , HeLa Cells , Humans , Mice , Molecular Sequence Data , Neuroblastoma , Rabbits , Trigeminal Ganglion/virology , Tumor Cells, Cultured
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