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1.
Zh Nevrol Psikhiatr Im S S Korsakova ; 123(11. Vyp. 2): 79-84, 2023.
Artigo em Russo | MEDLINE | ID: mdl-38127705

RESUMO

OBJECTIVE: To analyze the relationship between hostility and attachment disorders in endogenous depression. MATERIAL AND METHODS: The study included 49 patients with a diagnosis of depressive disorder, all of them completed the Simptom Check List-90-Revised (SCL-90R); the Buss-Perry Aggression Questionnaire; the Experiences in Close Relationships-Revised (ECR-R); Ich-Struktur-Test nach Ammon. The patients were assessed using the Hamilton Depression Rating Scale (HDRS-17). RESULTS: At high levels of depression, the indicators of «hostility¼ (p=0.046), «destructive aggression¼ (p=0.04) and «deficit aggression¼ (p=0.005) are significantly higher. The severity of depression significantly correlates with the severity of «anxiety¼ in attachment (close relationships), as well as with pathological «narcissism¼, «destructive external self-delimitation¼, «deficient internal self-delimitation¼ (p<0.05). For the measure of depression, the regression model explains more than 76% of the variance, with the measures of «interpersonal sensitivity¼, «deficit narcissism¼, and «avoidance¼ in attachment making significant contributions. For the «hostility¼ the regression model explains about 62% of the variance, while, as in the analysis of «depression¼, a significant contribution is made by the indicators of «interpersonal sensitivity¼ and «avoidance¼, however, unlike «depression¼, the contribution of the «destructive narcissism¼ is noted in contrast to the «deficit narcissism¼. CONCLUSIONS: With severe depressive symptoms, indicator of hostility are increased. Hostility in depression is associated with factors caused by a violation of early interpersonal relationships (anxious attachment) (which causes increased sensitivity in relations with others, building a barrier between oneself and the external environment perceived as hostile), the narcissistic pathology, problems in emotional regulation.


Assuntos
Depressão , Hostilidade , Humanos , Depressão/diagnóstico , Agressão/psicologia , Ansiedade/diagnóstico , Ansiedade/psicologia , Relações Interpessoais
2.
Acta Naturae ; 14(4): 94-100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36694902

RESUMO

Brain-derived neurotrophic factor (BDNF) is known to be involved in the pathogenesis of Alzheimer's disease (AD). However, the pharmacological use of full-length neurotrophin is limited, because of its macromolecular protein nature. A dimeric dipeptide mimetic of the BDNF loop 1, bis-(N-monosuccinyl-L-methionyl-L-serine) heptamethylene diamide (GSB-214), was designed at the Zakusov Research Institute of Pharmacology. GSB-214 activates TrkB, PI3K/AKT, and PLC-γ1 in vitro. GSB-214 exhibited a neuroprotective activity during middle cerebral artery occlusion in rats when administered intraperitoneally (i.p.) at a dose of 0.1 mg/kg and improved memory in the novel object recognition test (0.1 and 1.0 mg/kg, i.p.). In the present study, we investigated the effects of GSB-214 on memory in the scopolamine- and steptozotocin-induced AD models, with reference to activation of TrkB receptors. AD was modeled in rats using a chronic i.p. scopolamine injection or a single streptozotocin injection into the cerebral ventricles. GSB-214 was administered within 10 days after the exposure to scopolamine at doses of 0.05, 0.1, and 1 mg/kg (i.p.) or within 14 days after the exposure to streptozotocin at a dose of 0.1 mg/kg (i.p.). The effect of the dipeptide was evaluated in the novel object recognition test; K252A, a selective inhibitor of tyrosine kinase receptors, was used to reveal a dependence between the mnemotropic action and Trk receptors. GSB-214 at doses of 0.05 and 0.1 mg/kg statistically significantly prevented scopolamine-induced long-term memory impairment, while not affecting short-term memory. In the streptozotocin-induced model, GSB-214 completely eliminated the impairment of short-term memory. No mnemotropic effect of GSB-214 was registered when Trk receptors were inhibited by K252A.

3.
Artigo em Russo | MEDLINE | ID: mdl-34460163

RESUMO

OBJECTIVE: The results of the analysis of psychopathological symptom dynamics during the COVID-19 pandemic in Russia are presented. MATERIAL AND METHODS: The study uses the data of the Internet survey, which included a block of sociodemographic questions and the SCL-90-R symptomatic questionnaire. Nine hundred and eight responses received from 22.03.20 to 22.06.20 were analysed. The change in the responses over time was assessed: 3 periods of time were allocated, associated with the change in countermeasures to the pandemic in Russia. In addition, the change in the values of the SCL-90 parameters was assessed depending on the existence of respondent's acquaintances infected with the coronavirus. RESULTS: It was shown that SCL-90 symptoms (Somatization, Depression, Obsession, all integral parameters, including the Global Severity Index) increased from 22.03.20 to 22.06.20. With infected people appearing in the respondent's environment psychopathological symptoms increase. The growth of hostility, sensitivity and anxiety is associated with a personal experience of a danger of the pandemic, which intensifies when infected persons appear in the immediate environment. CONCLUSION: The increase in psychopathological symptoms after the mitigation or cancellation of the quarantine restrictions suggests the persistence of long-term consequences.


Assuntos
COVID-19 , Transtornos Mentais , Ansiedade/epidemiologia , Depressão/epidemiologia , Humanos , Transtornos Mentais/epidemiologia , Pandemias , Quarentena , SARS-CoV-2
4.
Dokl Biochem Biophys ; 493(1): 190-192, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32894462

RESUMO

Previously we have shown that the neuropeptide cycloprolylglycine is an endogenous positive modulator of AMPA receptors and assumed that the pharmacological effects of CPG are associated with the brain neurotrophic factor. In this paper, we have first demonstrated that DNQX, an inhibitor of AMPA receptors, and K252A, an ihibitor of Trk receptors, prevented the anxiolytic effect of CPG, which confirms the formulated hypothesis.


Assuntos
Transtornos de Ansiedade/tratamento farmacológico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Carbazóis/farmacologia , Alcaloides Indólicos/farmacologia , Glicoproteínas de Membrana/antagonistas & inibidores , Peptídeos Cíclicos/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinoxalinas/farmacologia , Receptores de AMPA/antagonistas & inibidores , Animais , Ansiolíticos/farmacologia , Transtornos de Ansiedade/metabolismo , Transtornos de Ansiedade/patologia , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos Cíclicos/química
5.
Adv Gerontol ; 32(1-2): 262-272, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31228400

RESUMO

A comprehensive study of socio-medical and constitutional aspects of longevity in Pridnestrovie (Transnistria) was carried out. The level of longevity, the frequency of occurrence of hereditary predisposition to longevity, the features of anthropometric indicators, the somatic and psychological constitution of long-livers, their state of health, degree of ability to self-service, marital status, professional activity and level of physical activity throughout life are revealed.


Assuntos
Longevidade , Condições Sociais , Nível de Saúde , Humanos , Federação Russa
6.
Artigo em Russo | MEDLINE | ID: mdl-25403302

RESUMO

OBJECTIVE: To identify the ability of schizophrenic patients to make decisions based on the mechanism of emotional learning (Damasio's somatic markers hypothesis). MATERIAL AND METHODS: Forty patients with the juvenile endogenous attack-like schizophrenia were investigated. Based on the clinical data, the patients were separated into three groups with different levels of negative symptoms. RESULTS AND CONCLUSION: In all groups the deficit in the emotional decision making mechanism increased along with the progress of the disorder and was connected with the decrease in the ability to adequately estimate self-emotional state, to integrate the ambivalent feeling and to make decisions in ambiguous environment based on the past emotional experience. The executive function and the mechanism of the emotional decision making were found to be independent neurocognitive mechanisms.


Assuntos
Tomada de Decisões , Emoções , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Biochemistry (Mosc) ; 79(5): 459-68, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24954597

RESUMO

Polysialic acid (PSA) is a natural anionic polymer typically occurring on the outer surface of cell membranes. PSA is involved in cell signaling and intermolecular interactions with proteins and peptides. The antimicrobial potential of peptides is usually evaluated in model membranes consisting of lipid bilayers but devoid of either PSA or its analogs. The goal of this work was to investigate the possible effect of PSA on the structure of melittin (Mlt) and latarcins Ltc1K, Ltc2a, and the activity of these peptides with respect to model membranes. These peptides are linear cationic ones derived from the venom of bee (Mlt) and spider (both latarcins). The length of each of the peptides is 26 amino acid residues, and they all have antimicrobial activity. However, they differ with respect to conformational mobility, hydrophobic characteristics, and overall charge. In this work, using circular dichroism spectroscopy, we show that the peptides adopt an α-helical conformation upon interaction with either PSA or phospholipid liposomes formed of either zwitterionic or anionic phospholipids or their mixtures. The extent of helicity depends on the amino acid sequence and properties of the medium. Based on small angle X-ray scattering data and the analysis of the fluorescence spectrum of the Trp residue in Mlt, we conclude that the peptide forms an oligomeric complex consisting of α-helical Mlt and several PSA molecules. Both latarcins, unlike Mlt, the most hydrophobic of the peptides, interact weakly with zwitterionic liposomes. However, they bind anionic liposomes or those composed of anionic/zwitterionic lipid mixtures. Latarcin Ltc1K forms associates on liposomes composed of zwitterionic/anionic lipid mixture. The structure of the peptide associates is either disordered or of ß-sheet conformation. In all other cases the studied peptides adopt predominately α-helical conformation. In addition, we demonstrate that PSA inhibits membranolytic activity of Mlt and latarcin Ltc1K. These data suggest that the peptides, due to their high conformational lability, can vary structural and amphiphilic properties in the presence of PSA. As a result, various scenarios of the interaction of the peptides with membranes, whose surface is abundant with anionic polysaccharides, can take place. This can account for difficulties in understanding the structure-functional relationships in interactions of linear cationic peptides with biological membranes.


Assuntos
Bicamadas Lipídicas/metabolismo , Peptídeos/metabolismo , Fosfolipídeos/química , Ácidos Siálicos/metabolismo , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Cátions/química , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Bicamadas Lipídicas/química , Lipossomos/química , Lipossomos/metabolismo , Meliteno/química , Meliteno/metabolismo , Dados de Sequência Molecular , Peptídeos/química , Ligação Proteica , Estrutura Secundária de Proteína , Ácidos Siálicos/química , Venenos de Aranha/química , Venenos de Aranha/metabolismo
8.
Acta Naturae ; 5(3): 84-91, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24303204

RESUMO

Dipeptide mimetic of the nerve growth factor (NGF) loop 4, hexamethylenediamide bis-(N-monosuccinyl- glutamyl-lysine) (GK-2), was synthesized at the V.V. Zakusov Scientific Research Institute of Pharmacology of the Russian Academy of Medical Sciences. GK-2 exhibited in vitro neuroprotective activity at nanomolar concentrations, was efficient in animal models of the Parkinson's disease, ischemic and hemorrhagic stroke, and global cerebral ischemia at doses of 0.01-5 mg/kg (intraperitoneally) and 10 mg/kg (per os). The mnemotropic effects of subchronic intraperitoneal administration of GK-2 on rat models of the Alzheimer's disease are described in this paper. Dipeptide GK-2 at a dose of 1 mg/kg is found to decrease the habituation deficit induced by the septo-hippocampal pathway transsection and, at a dose of 0.5 mg/kg, to significantly prevent spatial memory impairment in Morris water maze induced by intracerebral injection of streptozotocin. Thus, GK-2, an original dipeptide mimetic of NGF, acts on models of the Alzheimer's disease upon systemic administration.

9.
Eksp Klin Farmakol ; 75(9): 15-20, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23156082

RESUMO

The behavioral and biochemical effects of a new dipeptide mimetic of the GK-2 nerve growth factor (NGF) have been studied on a model of chronic cerebral ischemia induced by permanent common carotid artery occlusion in rats. It is established that subchronic intraperitoneal injections of GK-2 (0.5 mg/kg) 4 h after surgery, followed by seven more injections made every 24 h, fully prevent the death of operated animals and reduces the development of habitation deficit (open-field test) and decrease in exploratory activity (novel object examination) two weeks after surgery, as well as fully restores the viability of cerebral cortex cells and decreases the hyperexpression of HSP70 in cerebral cortex.


Assuntos
Materiais Biomiméticos/farmacologia , Isquemia Encefálica/tratamento farmacológico , Dipeptídeos/farmacologia , Fator de Crescimento Neural/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Transtornos Cerebrovasculares/tratamento farmacológico , Transtornos Cerebrovasculares/metabolismo , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/fisiopatologia , Doença Crônica , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/biossíntese , Masculino , Proteínas do Tecido Nervoso/biossíntese , Ratos
10.
Bull Exp Biol Med ; 153(1): 44-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22808490

RESUMO

Glycine stabilizes energetics of brain mitochondria under conditions of brain hypoxia in vivo modeled by ligation of the common carotid artery in rats. Hypoxia reduced respiratory control in brain cortex mitochondria from 7.7 ± 0.5 to 4.5 ± 0.3. Preliminary oral administration of glycine almost completely prevented this decrease. In both in vitro models of hypoxia, similar phosphorylation disturbances were detected in both cortical slices and isolated brain mitochondria; they were effectively prevented by glycine. Hypoxia activates H(2)O(2) generation in mitochondrial suspension. The process is significantly reduced in the presence of 5 mM glycine. It is concluded that both in the model of hypoxia in vivo and during in vitro modeling of hypoxia in cortical slices and mitochondria, glycine acts as a protector inhibiting generation of reactive oxygen species in mitochondria and preventing energetics disturbances in brain mitochondria.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Glicina/farmacologia , Glicina/uso terapêutico , Hipóxia Encefálica/tratamento farmacológico , Animais , Isquemia Encefálica/metabolismo , Hipóxia Encefálica/metabolismo , Técnicas In Vitro , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo
11.
Bull Exp Biol Med ; 151(6): 690-3, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22485209

RESUMO

An intraperitoneal injection of GK-2 (dipeptide mimetic of nerve growth factor, 0.01-5.00 mg/kg) 24 h before the adverse exposure reduced the severity of haloperidol-induced catalepsy in rats. This agent retained the activity after oral administration in a dose of 10 mg/kg. An intraperitoneal injection of GK-2 in a dose of 1 mg/kg reduced the severity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian syndrome in mice. Administration of GK-2 45 min after haloperidol treatment was also followed by a decrease in the degree of catalepsy. The repeated intraperitoneal treatment with GK-2 in a dose of 1 mg/kg after intrastriatal injection of 6-hydroxydopamine was shown to prevent the development of apomorphine-induced rotations in rats.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Antiparkinsonianos/uso terapêutico , Catalepsia/tratamento farmacológico , Dipeptídeos/uso terapêutico , Haloperidol/farmacologia , Oxidopamina/farmacologia , Transtornos Parkinsonianos/tratamento farmacológico , Animais , Catalepsia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transtornos Parkinsonianos/induzido quimicamente , Ratos
12.
Neurosci Behav Physiol ; 38(5): 443-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18607757

RESUMO

Opiate dependence results from impairments of neuronal plasticity, i.e., so-called aberrant neuroplasticity, formation of which involves long-term structural-functional rearrangements persisting even during drug abstinence. Nitric oxide (NO) is involved both in mediating the effects of opiates and in the mechanisms of some types of neuroplasticity, so NO may potentially take part in the development of psychopathological processes on opiate withdrawal. The present study addressed measures of the nitrergic system (nitric oxide synthase (NOS) activity and nitrite and nitrate (NO (x) (-) ) concentrations) in areas of the rat brain; anxiety was also assessed, in terms of behavioral measures in the elevated plus maze, during morphine withdrawal. NOS activity was found to increase by day 3, while the NO (x) (-) concentration was increased by day 6 of withdrawal, these changes being seen only in the hippocampus. At six days after morphine withdrawal, rats showed more entries into the open arms of the elevated plus maze and remained in these arms longer. Correlations were found between measures of the NO system in the hippocampus and the behavior of the animals in the maze. These results suggest that changes in the activity of the nitrergic system in the hippocampus represent one of the molecular mechanisms impairing the behavior of animals in abstinence.


Assuntos
Ansiedade/metabolismo , Hipocampo/metabolismo , Morfina/farmacologia , Entorpecentes/farmacologia , Óxido Nítrico Sintase/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Animais , Ansiedade/complicações , Ansiedade/psicologia , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Hipocampo/efeitos dos fármacos , Masculino , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Nitratos/metabolismo , Ácido Nítrico/metabolismo , Ratos , Ratos Wistar , Síndrome de Abstinência a Substâncias/complicações , Síndrome de Abstinência a Substâncias/psicologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Fatores de Tempo
13.
Ross Fiziol Zh Im I M Sechenova ; 93(4): 357-65, 2007 Apr.
Artigo em Russo | MEDLINE | ID: mdl-17654860

RESUMO

Opiate addiction is accompanied by long-term structural and functional changes in brain regions persisting during abstinence, this status being an experimental model of the aberrant neuroplasticity. Nitric oxide is known to be involved in mechanisms of psychopathological events during opiate abstinence. In this study, indices of a nitregic system (nitric synthase activity--NOS, nitrites and nitrates concentration--NOx-) were measured in the rat brain region during morphine abstinence. Prior to this, the rats were tested for anxiety in an elevated plus maze. NOS activity increased in hippocampus 3 days after morphine withdrawal, while NOx--6 days after withdrawal. No changes of the nitrergic system could be revealed in other brain regions under study. Six days (but not 3 days) after morphine withdrawal, rats visited the open arms of the plus maze more frequently and spent more time in these arms as compared with respective controls. The data suggest that nitrergic system changes in the hippocampus may be involved in molecular mechanisms of behavioural alteration during morphine abstinence in rats.


Assuntos
Ansiedade/induzido quimicamente , Hipocampo/metabolismo , Morfina/efeitos adversos , Entorpecentes/efeitos adversos , Óxido Nítrico/metabolismo , Síndrome de Abstinência a Substâncias , Animais , Ansiedade/metabolismo , Hipocampo/química , Masculino , Nitratos/análise , Nitratos/metabolismo , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/metabolismo , Nitritos/análise , Nitritos/metabolismo , Ratos , Ratos Wistar
14.
Artigo em Russo | MEDLINE | ID: mdl-16756133

RESUMO

Rats received intracerebroventricular injections of z-DEVD-FMK (caspase-3 inhibitor) or z-FA-FMK (control peptide) in a dose of 3 nmol. Administration of z-DEVD-FMK significantly decreased the number of avoidance reactions in some blocks of trials in active avoidance (shuttle box) learning. However, only slight effect of the caspase inhibitor across the session was found. Z-DEVD-FMK impaired development of some essential components of the two-way active avoidance performance, such as escape reaction, conditioned fear reaction, and inter-trial crossings. Z-DEVD-FMK did not impair working memory in the spontaneous alternation behavior paradigm. Z-DEVD-FMK affected neither emotionality nor locomotor activity in the open-field test. It also did not influence behavior in the light-dark chamber. Measurement of caspase-3 activity in rat brain regions involved in active avoidance learning revealed z-DEVD-FMK-related inhibition of the enzyme activity most pronounced (about 30%) in the fronto-parietal cortex; a similar effect was close to significant in the hippocampus. The results suggest the involvement of brain caspase-3 in selected forms of learning.


Assuntos
Inibidores de Caspase , Córtex Cerebral/enzimologia , Inibidores de Cisteína Proteinase/administração & dosagem , Reação de Fuga/efeitos dos fármacos , Hipocampo/enzimologia , Oligopeptídeos/administração & dosagem , Animais , Caspase 3 , Caspases/análise , Injeções Intraventriculares , Aprendizagem , Ratos
15.
Vopr Virusol ; 50(1): 9-14, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15747864

RESUMO

31 prematures with signs of the cytomegalovirus infection (CMV) were examined. The blood and urine samples were tested for direct viral markers, i.e. for infectious CMV by the rapid culture method (RCM) and for viral DNA by quantitative PCR. Besides, the parameters of the specific immune response were studied in the babies. CMV was detected by RCM and/or PCR in 25 of the 31 examined babies during their 1st life week. The highest content of CMV within the investigated samples, i.e. 100 antigen-containing cells per 2.5 x 10(5) culture cells and above 2000 copies/ml of viral DNA was detected in 8 (32%) children. The quantity of viral DNA did not exceed 1000 copies/ml and one to three of stained cells was detected by PCR in 13 (42%) children. A study of anti-CMV in sera revealed high-titer of AT IgG in all 30 children. High avidity of anti-CMV-IgG was demonstrated to correlate with a low viral load and a low CMV infection activity in the newborns. According to the results, at least 3 laboratory diagnosis tools should be used in the diagnosis, they are PCR, RCM and determination of the anti-CMV avidity.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , Recém-Nascido Prematuro , Anticorpos Antivirais/sangue , Afinidade de Anticorpos , Antígenos Virais/sangue , Antígenos Virais/urina , Células Cultivadas , Citomegalovirus/genética , Citomegalovirus/imunologia , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/urina , DNA Viral/sangue , DNA Viral/urina , Humanos , Imunoglobulina G/sangue , Recém-Nascido , Recém-Nascido Prematuro/sangue , Recém-Nascido Prematuro/urina , Reação em Cadeia da Polimerase , Cultura de Vírus
16.
Genomics ; 70(3): 327-34, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11161783

RESUMO

Previous studies have indicated the presence of a putative tumor suppressor gene on human chromosome 13q14, commonly deleted in patients with B-cell chronic lymphocytic leukemia (B-CLL). We have recently identified a minimally deleted region encompassing parts of two adjacent genes, termed LEU1 and LEU2 (leukemia-associated genes 1 and 2), and several additional transcripts. In addition, 50 kb centromeric to this region we have identified another gene, LEU5/RFP2. To elucidate further the complex genomic organization of this region, we have identified, mapped, and sequenced the homologous region in the mouse. Fluorescence in situ hybridization analysis demonstrated that the region maps to mouse chromosome 14. The overall organization and gene order in this region were found to be highly conserved in the mouse. Sequence comparison between the human deletion hotspot region and its homologous mouse region revealed a high degree of sequence conservation with an overall score of 74%. However, our data also show that in terms of transcribed sequences, only two of those, human LEU2 and LEU5/RFP2, are clearly conserved, strengthening the case for these genes as putative candidate B-CLL tumor suppressor genes.


Assuntos
Cromossomos Humanos Par 13 , Leucemia Linfocítica Crônica de Células B/genética , Deleção de Sequência , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA , Genes Supressores de Tumor , Humanos , Hibridização in Situ Fluorescente , Camundongos , Proteínas de Neoplasias/genética
17.
Biopolymers ; 31(1): 65-76, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2025685

RESUMO

Polyriboadenylates of alkali metals were obtained from (1) K(+)-poly(A) (salts 1) and (2) H(+)-poly(A) (salts II) by the ion-exchange method. The conductivity of these salts as well as of H(+)-poly(A) were studied. Salts I and II of the same counterion were shown to have significantly different conductivity coefficients (f) and polyion conductances (lambda 0p). the charge density parameter (xi) was 1.3 and 2.5, respectively, with lambda 0p equal to 44 and 83 ohm-1 cm2 mole-1 for poly(A)-I and poly(A)-II salts, respectively. This is credited to the difference in the conformations of corresponding polyions. The linear dependence of equivalent conductivity on the square root of polymer concentration (Kohlrausch coordinates), earlier obtained for DNA, is also satisfied for the studied polynucleotides. A comparison of the slopes of straight lines in Kohlrausch coordinates for poly(A), simple electrolytes, and for earlier studied polyribouridylic acid salts lends credence to the concepts, developed by a number of authors, that DNA can act as a "buffer" against the ion-ion interaction in concentrated electrolyte solutions. Using the approximation that the polyion conductance is independent of the counterion nature, parameter f (agreeing in this case with Eisenberg parameter phi) has been shown to decrease as the polynucleotide concentration is increased; the decrease is caused by the relaxation effect. The transference numbers of counterions, which have negative values in poly (A)-II solutions, grow with the increase in polymer concentration; the higher the xi, the more apparent is this increase. This is explained by the increase in the fraction of conductivity along the polyion chains ("surface" conductivity) with the growth of polyelectrolyte concentration.


Assuntos
Poli A/química , Condutividade Elétrica , Metais Alcalinos/química , Conformação Molecular , Poli U/química , Sais , Soluções
18.
Mol Biol (Mosk) ; 18(4): 1032-41, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6095021

RESUMO

It is shown that there are three parts on the potentiometric titration curves of isoionic solutions of poly(A) ascribed to the three protonated structures. Double-helical protonated structures are especially stable in isoionic solution. These parts on potentiometric curves are attributed to the single-stranded poly(A), to the completely protonated double-stranded poly(A+).poly(A+), and to the semiprotonated poly(A+).poly(A) structures: D, A, B forms of poly(A), respectively. pK0 values of these forms are calculated. The D form portion is found to be about 18% in isoionic solution, 40% in KCl solution (from 0.01 to 1.0 M), 40% in solution, containing 1.2 X 10(-3) M MgCl2 and 70% in 8 X 10(-4) M MgCl2 solution. The increase of MgCl2 concentration up to 8 X 10(-4) M leads to complete degradation of the double-helical structure. Only single-stranded D form exists in 5 X 10(-3) M MgCl2 solution. About 5-7% of all protons become inaccessible for titration in all solutions containing KCl and in the presence of small amounts of MgCl2. This phenomenon can not be explained by aggregation of poly(A), because all protons become accessible for titration in more concentrated MgCl2 solution when aggregation of poly(A) is significant and accompanied by the precipitation of sediment insoluble in NaOH. The supposition is made, that unprotonated double-stranded poly(A) can exist in salt-free solution at neutral pH. It is this form that is protonated with decrease of pH.


Assuntos
Poli A , Fenômenos Químicos , Físico-Química , Condutometria , Cinética , Magnésio , Potenciometria , Prótons , Soluções
19.
Biofizika ; 29(4): 560-3, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6487665

RESUMO

Conductometric and spectrophotometric investigations of concentrated salt-free solutions of poly(A) -- poly(U) demonstrated the 1:1 complex formation. It was accomplished by the increase of solution conductivity in contrast to the situation when DNA redenaturation takes place.


Assuntos
Poli A , Poli U , Condutometria , DNA , Condutividade Elétrica , Desnaturação de Ácido Nucleico , Espectrofotometria
20.
Mol Biol (Mosk) ; 17(2): 392-402, 1983.
Artigo em Russo | MEDLINE | ID: mdl-6855764

RESUMO

Equivalent conductivity (lambda MeP) was studied for the Li+, Na+, K+, Cs+, NH4+ salts of poly(U) and for polyribouridilic acid. Concentration of the salt free solutions of poly(U) ranges from 1 . 10(-4) M-3 . 10(-3) M. Limiting equivalent conductivity (lambda 0 MeP) was obtained based on linear dependence of lambda MeP on Cp1/2 (where Cp is the concentration of nucleic phosphorus). The lambda 0 MeP values obtained were shown to increase linearly with the increase of the limiting mobility of counterion. These data were used to calculate limiting mobility of macroion (lambda p = 43 Ohm-1 Cm2 equiv-1) and parameter xi = 1.13 which characterizes charge density on a macroion. Linear dependence was shown to take place for poly(U) acid and it's salts in the Ostwald's coordinates; moreover, pK value for the phosphate groups is practically independent of the counterion's nature and equal 1.93 +/- 0.32.


Assuntos
Poli U , Cátions Monovalentes , Condutividade Elétrica , Cinética , Sais , Soluções
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