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1.
Pathogens ; 12(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37513734

RESUMO

A misdiagnosis of isolated pulmonary tuberculosis (pTB) is highly likely when a patient has nontuberculous mycobacterial pulmonary disease (NTMPD) or a combination of nontuberculous mycobacterium pulmonary disease and pulmonary tuberculosis. Frequently, bacterial excretion is absent or only Mycobacteria tuberculosis (MBT) is found. This often results in an incorrect diagnosis and subsequent misinformed treatment regimes. In order to determine possible clinical and radiographic differences between patients with NTMPD (Group 1), destructive drug-resistant pulmonary tuberculosis (Group 3) and a combination of NTMPD and pTB (Group 2) we compare clinical and radiographic signs for these three patient groups. When comparing with Group 3 (2.5%), Groups 1 (25%) and 2 (17.4%) have a substantially higher incidence of pulmonary haemorrhages. Thus, upon clinically observing the combination of pTB and NTMPD, there are no pathognomonic clinical and radiographic detected symptoms. However, the presence of an indolent course, hemoptysis and bronchiectasis in the presence of acid-fast bacteria (or identified MBT) in the sputum makes it possible to suspect not simple pTB, but a combination of pTB and NTMPD. To clarify this necessitated in-depth bacteriological examination.

2.
PLoS One ; 18(2): e0272837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36791129

RESUMO

The current study investigated the features of cross-cultural recognition of four basic emotions "joy-neutral (calm state)-sad-anger" in the spontaneous and acting speech of Indian and Russian children aged 8-12 years across Russian and Tamil languages. The research tasks were to examine the ability of Russian and Indian experts to recognize the state of Russian and Indian children by their speech, determine the acoustic features of correctly recognized speech samples, and specify the influence of the expert's language on the cross-cultural recognition of the emotional states of children. The study includes a perceptual auditory study by listeners and instrumental spectrographic analysis of child speech. Different accuracy and agreement between Russian and Indian experts were shown in recognizing the emotional states of Indian and Russian children by their speech, with more accurate recognition of the emotional state of children in their native language, in acting speech vs spontaneous speech. Both groups of experts recognize the state of anger via acting speech with the high agreement. The difference between the groups of experts was in the definition of joy, sadness, and neutral states depending on the test material with a different agreement. Speech signals with emphasized differences in acoustic patterns were more accurately classified by experts as belonging to emotions of different activation. The data showed that, despite the universality of basic emotions, on the one hand, the cultural environment affects their expression and perception, on the other hand, there are universal non-linguistic acoustic features of the voice that allow us to identify emotions via speech.


Assuntos
Percepção da Fala , Fala , Humanos , Criança , Adulto , Comparação Transcultural , Percepção da Fala/fisiologia , Índia , Emoções/fisiologia , Idioma
3.
Biochimie ; 204: 136-139, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36174793

RESUMO

Mitoregulin (Mtln) is a recently identified 56 amino acid long mitochondrial peptide conserved in vertebrates. Mtln is known to enhance function of respiratory complex I, which is likely mediated by modulation of lipid composition. To address an influence of Mtln gene on the metabolism we created knockout mice deficient in Mtln gene. In line with accumulation of triglycerides observed earlier on a model of Mtln knockout cell lines, we observed Mtln KO mice to develop obesity on a high fat diet. An increased weight gain could be attributed to enhanced fat accumulation according to the magnetic resonance live imaging. In addition, Mtln KO mice demonstrate elevated serum triglycerides and other oxidation substrates accompanied by an exhaustion of tricarboxylic acids cycle intermediates, suggesting suboptimal oxidation of respiration substrates by mitochondria lacking Mtln.


Assuntos
Mitocôndrias , Aumento de Peso , Camundongos , Animais , Mitocôndrias/metabolismo , Peptídeos/metabolismo , Triglicerídeos/metabolismo , Camundongos Knockout , Dieta Hiperlipídica/efeitos adversos , Estresse Oxidativo , Metabolismo dos Lipídeos
4.
Trop Med Infect Dis ; 7(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35736965

RESUMO

To date, tuberculosis (TB) remains the primary cause of mortality in human immunodeficiency virus (HIV) patients in Russia. Since the beginning of 2000, a sharp change in the HIV patients' structure, to the main known risk factors for HIV infection has taken place in Russia. The transmission of HIV through injectable drug use has begun to decline significantly, giving way to the prevalence of sexual HIV transmission today. These changes may require adjustments to organizational approaches to anti-TB care and the treatment of HIV-positive patients. Our study is aimed at identifying changes in TB-HIV coinfection patients' structures in 2019 compared to 2000. Based on the results obtained, our goal was to point out the parameters that need to be taken into account when developing approaches to improve the organization of TB control care for people with HIV infection. We have carried out a cross-sectional, retrospective, epidemiological study using government TB registry data from four regions in two federal districts of Russia in 2019. The case histories of 2265 patients from two regions with high HIV prevalence, which are part of the Siberian Federal District of Russia, and 89 patient histories from two regions of low HIV prevalence, which are part of the Central Federal District of Russia, were analyzed. We found that parenteral transmission (69.4%) remains the primary route of HIV transmission among the TB-HIV coinfected. The unemployed of working age without disability account for 80.2% of all coinfected people, while the formerly incarcerated account for 53.7% and the homeless account for 4.1%. Those with primary multidrug-resistant TB (MDR-TB) comprise 56.2% of HIV-TB patients. When comparing the incidence of coinfection with HIV among TB patients, statistically significant differences were obtained. Thus, the chances of coinfection increased by 4.33 times among people with active TB (95% CI: 2.31; 8.12), by 2.97 times among people with MDR-TB (95% CI: 1.66; 5.32), by 5.2 times in people with advanced processes in the lungs, including destruction, (95% CI: 2.78; 9.7), as well as by 10.3 times in the case of death within the first year after the TB diagnosis (95% CI: 2.99; 35.5). The absence of data for the presence of TB during preventive examination was accompanied by a decrease in the chances of detecting coinfection (OR 0.36; 95% CI: 0.2; 0.64). We have identified the probable causes of the high incidence of TB among HIV-infected: HIV-patient social maladaptation usually results in delayed medical care, leading to TB treatment regimen violations. Furthermore, self-administration of drugs triggers MDR-TB within this group. Healthcare providers should clearly explain to patients the critical importance of immediately seeking medical care when initial TB symptoms appear.

5.
J Pharmacol Toxicol Methods ; 113: 107128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34678429

RESUMO

Metabolic chambers are routinely used for urine collection in rodents. In mice, due to small urination volume, evaporation in the metabolic chambers (≈50%) distorts diuresis and urinalysis parameters. We have developed a new technique of bladder catheterization enabling long-term accurate and contamination-free urine collection in awake male and female mice for 30 days or longer. Daily diuresis in catheterized mice was twice higher as compared to metabolic cages. The twofold difference in urine recovery was preserved when the circadian variation of diuresis, the effects of furosemide, desmopressin and water load were estimated using the two techniques. Urine osmolarity, urinalysis, and microbiological parameters evidence higher quality of the catheter-collected urine. Using phenol red, we demonstrate utility of our technique for pharmacokinetic studies. 30 days after the surgery the catheters were patent and had minimal impact on the animals' heath. Bladder catheterization is a useful tool for physiological, pharmacological, and toxicological studies.


Assuntos
Bexiga Urinária , Coleta de Urina , Animais , Diurese , Feminino , Masculino , Camundongos , Cateterismo Urinário , Vigília
6.
Front Pharmacol ; 12: 679511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413772

RESUMO

Kagocel is a synthetic carboxymethylcellulose derivative copolymerized with gossypol. Clinical data evidence its safety and efficiency for the treatment of flu and other viral infections via enhancement of interferon production. The gut-associated lymphoid tissue seems a likely site of kagocel action. The study was aimed to investigate the molecular mechanisms of its action using murine Peyer's patches lymphocytes as a test system and the cytokines production and gene expression patterns as the primary outcomes. The Peyer's patches lymphocytes isolated from BALB/c mice were stimulated with concanavalin A, or, to mimic viral infection, with a combination of concanavalin A and TLR3 ligand poly I:C. After 24 h of stimulation the cells were treated with saline, 30, 100, or 300 µg/ml of kagocel, or, as positive controls, 300 µg/ml oats b-D-glucan or 300 µg/ml lentinan. After 24 and 72 h of incubation with these drugs cytokines production was analyzed with ELISA and gene expression pattern was investigated using nCounter Inflammation panel chips followed by bioinformatics analysis. Expression of genes involved in the inflammatory response, antiviral defense, lymphocytes survival and proliferation (C1qa, C2, C3, Ccl21a, Il11, Il1b, Il23a, Il5, Ltb4r2, Alox15, Pla2g4a, Ptger1, Mapkapk5, Hras, Ifna1, Tlr2, Mrc1, Mx2) was upregulated in kagocel-treated Peyer's patches lymphocytes. A list of plausible transcription factors (CEBPs, IRF, NFκB, RXR, Stat, Tead4, and ZSCAN) and master-regulators has been identified (cIAP, CIKS, dock9, MEKK1, FXR, IKK, IRAK, TRAF, dsRNA:TLR3:TRIF). The changes in gene expression pattern and the outcomes of bioinformatics analysis suggest that pattern recognition receptors, TLRs and dectin-1, are the key mediators of kagocel immunomodulatory action, with the possible involvement of interferon autocrine loop. The genes upregulated with kagocel include diverse components of the innate immune defense system.

7.
Biochemistry (Mosc) ; 86(7): 878-886, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34284711

RESUMO

The effects of superoxide dismutase (SOD) inhibitors, diethyldithiocarbamate (DDC), triethylenetetramine (trien), and their combination with glucose on cells of the epidermis from pea leaves of different age (rapidly growing young leaves and slowly growing old leaves) was investigated. DDC and trien caused death of the guard cells as determined by destruction of their nuclei. Glucose did not affect destruction of the nuclei induced by SOD inhibitors in the cells from old leaves, but intensified it in the cells from young leaves. 2-Deoxyglucose, an inhibitor of glycolysis, and propyl gallate, SOD-mimic and antioxidant, suppressed destruction of the nuclei that was caused by SOD inhibitors and glucose in cells of the epidermis from the young, but not from the old leaves. Glucose and trien stimulated, and propyl gallate reduced generation of reactive oxygen species (ROS) in the pea epidermis as determined by the fluorescence of 2',7'-dichlorofluorescein (DCF). Carbonyl cyanide m-chlorophenylhydrazone (CCCP), a protonophoric uncoupler of oxidative and photosynthetic phosphorylation, suppressed the DCF fluorescence in the guard cells. Treatment of the cells with CCCP followed by its removal with washing increased destruction of the nuclei caused by SOD inhibitors and glucose. In young leaves, CCCP was less effective than in old ones. The findings demonstrate the effects of SOD inhibitors and glucose on the cell death and generation of ROS and could indicate glycolysis-dependent ROS production.


Assuntos
Ditiocarb/farmacologia , Glucose/metabolismo , Pisum sativum/efeitos dos fármacos , Epiderme Vegetal/efeitos dos fármacos , Espécies Reativas de Oxigênio , Superóxido Dismutase/antagonistas & inibidores , Trientina/farmacologia , Morte Celular , Quelantes/farmacologia , Inibidores Enzimáticos/farmacologia , Glucose/farmacologia , Pisum sativum/enzimologia , Pisum sativum/metabolismo , Pisum sativum/fisiologia , Epiderme Vegetal/enzimologia , Epiderme Vegetal/metabolismo , Epiderme Vegetal/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia
8.
Front Behav Neurosci ; 14: 30, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231524

RESUMO

The goal of the study is to investigate a correlation between different levels of speech organization, indicating the physiological processes of maturation of the vocal tract structures and brain regions associated with speech and language, and basic electroencephalogram (EEG) rhythms, reflecting the age-related dynamics of maturation of brain structures in children aged 4-11 years. The complex method of analysis, including EEG registration, clinical and spectral analysis of EEG; dichotic listening, identifying the profile of functional lateral asymmetry (PFLA), and phonemic hearing of the child; recording, linguistic, and acoustic analysis of child speech; and identification of speech characteristics reflecting the formation of its different levels, was used. Two complementary experimental series were conducted: the correlation between EEG parameters, speech features, dichotic listening, the PFLA, and phonemic hearing of the child in the age dynamics of 4-11 years (first); the specificity of EEG patterns in children at different stages of reading skills formation (second). The result of this study showed the correlation between acoustic and linguistic features of child speech and brain activity. The analysis of EEG and acoustic features of child speech revealed the correlation between pitch and pitch range values in spontaneous speech and theta-rhythm intensity in EEG. High values of pitch and its variation in younger children (4-6 years) are related to the intensity of theta rhythm in the EEG pattern, as this rhythm is most expressed in younger children. It was revealed that the alpha rhythm is asymmetrically localized in children with clear pronunciation of words (which determines the intelligibility of their speech) that is typical for 6.5- to 11-year-old children. The formation of reading skills in a child is associated with a change in the characteristics of the alpha rhythm-from irregular, unstable, low frequency, and low amplitude in children at the beginning of reading skills mastering to medium and low amplitude, regular, asymmetrically localized in children reading words and phrases. The specifics of the relation between brain activity and different levels of speech formation at different child's age periods are discussed.

9.
Metabolites ; 10(4)2020 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-32260384

RESUMO

Intestinal microbiota play a considerable role in the host's organism, broadly affecting its organs and tissues. The kidney can also be the target of the microbiome and its metabolites (especially short-chain fatty acids), which can influence renal tissue, both by direct action and through modulation of the immune response. This impact is crucial, especially during kidney injury, because the modulation of inflammation or reparative processes could affect the severity of the resulting damage or recovery of kidney function. In this study, we compared the composition of rat gut microbiota with its outcome, in experimental acute ischemic kidney injury and named the bacterial taxa that play putatively negative or positive roles in the progression of ischemic kidney injury. We investigated the link between serum creatinine, urea, and a number of metabolites (acylcarnitines and amino acids), and the relative abundance of various bacterial taxa in rat feces. Our analysis revealed an increase in levels of 32 acylcarnitines in serum, after renal ischemia/reperfusion and correlation with creatinine and urea, while levels of three amino acids (tyrosine, tryptophan, and proline) had decreased. We detected associations between bacterial abundance and metabolite levels, using a compositionality-aware approach-Rothia and Staphylococcus levels were positively associated with creatinine and urea levels, respectively. Our findings indicate that the gut microbial community contains specific members whose presence might ameliorate or, on the contrary, aggravate ischemic kidney injury. These bacterial taxa could present perspective targets for therapeutical interventions in kidney pathologies, including acute kidney injury.

10.
Alcohol ; 83: 17-28, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31260795

RESUMO

Chronic ethanol consumption in high doses is associated with constitutively elevated activity of the serum alcohol dehydrogenase I (ADH I) isoform, which demonstrates a high affinity not only for ethanol but also for a number of bioamine metabolites. Such excessive ADH activity is probably associated with disruptions in the metabolism of neurotransmitters (dopamine, serotonin, and norepinephrine) and subsequent long-term changes in the activity of their receptors. Ultimately, a stable depressive-like condition contributes to the development of patients' craving for ethanol intake, frequent disruptions during therapy, and low efficacy of treatment. We applied active immunization against ADH to investigate its efficacy in the reduction of excessive serum ADH activity and regulation of ethanol consumption by chronically ethanol-fed Wistar rats (15% ethanol, 4 months, free-choice method), and we analyzed its ability to influence the levels of bioamines in the brain. Immunization (2 injections, 2-week intervals) was performed using a combination of recombinant horse ADH isozyme as an antigen and 2% aluminum hydroxide-based adjuvant. The efficacy of immunization was demonstrated by the production of high titers of ADH-specific antibodies, which was consistent with the significantly reduced ADH activity in the serum of chronically ethanol-fed rats. On the 26th day after the first vaccine injection, we registered significantly lower levels of alcohol consumption compared to ethanol-fed control animals, and the difference reached 16% on the 49th day of the experiment. These observations were accompanied by data that showed reduced levels of ethanol preference in immunized rats. Chronic alcohol drinking led to a decrease in dopamine and DOPAL (a direct dopamine metabolite and a high-affinity ADH substrate) levels in the striatum,while immunization neutralized this effect. Additionally, we observed that inhibition of serum ADH activity caused a decrease in peak dopamine levels during acute alcohol intake in chronically ethanol-fed rats during ethanol withdrawal that was associated with reduced tyrosine hydroxylase activity in the striatum. The obtained data suggest a significant contribution of ADH to the changes in neurotransmitter systems during chronic alcohol consumption and make available new prospects for developing innovative strategies for treatment of excessive alcohol intake.


Assuntos
Álcool Desidrogenase/sangue , Álcool Desidrogenase/imunologia , Alcoolismo/enzimologia , Vacinação , Álcool Desidrogenase/metabolismo , Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/terapia , Animais , Anticorpos/sangue , Dopamina/sangue , Etanol/administração & dosagem , Etanol/sangue , Neurotransmissores/metabolismo , Ratos , Ratos Wistar
11.
Behav Sci (Basel) ; 9(12)2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888116

RESUMO

The goal of this research is to study the speech strategies of adults' interactions with 4-7-year-old children. The participants are "mother-child" dyads with typically developing (TD, n = 40) children, children with autism spectrum disorders (ASDs, n = 20), Down syndrome (DS, n = 10), and "experimenter-orphan" pairs (n = 20). Spectrographic, linguistic, phonetic, and perceptual analyses (n = 465 listeners) of children's speech and mothers' speech (MS) are executed. The analysis of audio records by listeners (n = 10) and the elements of nonverbal behavior on the basis of video records by experts (n = 5) are made. Differences in the speech behavior strategies of mothers during interactions with TD children, children with ASD, and children with DS are revealed. The different strategies of "mother-child" interactions depending on the severity of the child's developmental disorders and the child's age are described. The same features of MS addressed to TD children with low levels of speech formation are used in MS directed to children with atypical development. The acoustic features of MS correlated with a high level of TD child speech development do not lead to a similar correlation in dyads with ASD and DS children. The perceptual and phonetic features of the speech of children of all groups are described.

12.
J Neuroinflammation ; 15(1): 196, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973231

RESUMO

BACKGROUND: Lipopolysaccharide (LPS) is one of the main constituents of the cell wall of gram-negative bacteria. As an endotoxin, LPS induces neuroinflammation, which is associated with the blood-brain barrier impairment. Lactate is a metabolite with some significant physiological functions within the neurovascular unit/blood-brain barrier (BBB). Accumulation of extracellular and cerebrospinal fluid lactate is a specific feature of bacterial meningitis. However, the role of lactate production, transport, and sensing by lactate receptors GPR81 in the pathogenesis of bacterial neuroinflammation is still unknown. METHODS: In this study, we analyzed effects of LPS on the expression of GPR81 and MCT-1 and proliferation of cerebral endothelial cells in the BBB model in vitro. We used molecular profiling methods to measure the expression of GPR81, MCT-1, IL-1ß, and Ki67 in the cerebral endothelium after treatment with different concentrations of LPS followed by measuring the level of extracellular lactate, transendothelial electric resistance, and permeability of the endothelial cell layer. RESULTS: Our findings showed that exposure to LPS results in neuroinflammatory changes associated with decreased expression of GPR81 and MCT-1 in endothelial cells, as well as overproduction of IL-1ß and elevation of lactate concentrations in the extracellular space in a dose-dependent manner. LPS treatment reduced JAM tight junction protein expression in cerebral endothelial cells and altered BBB structural integrity in vitro. CONCLUSION: The impairment of lactate reception and transport might contribute to the alterations of BBB structural and functional integrity caused by LPS-mediated neuroinflammation.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Lipopolissacarídeos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Permeabilidade Capilar/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Células Endoteliais , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/metabolismo , Antígeno Ki-67/metabolismo , Camundongos , Modelos Biológicos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neuroglia , Neurônios , Ratos Wistar , Receptores de Superfície Celular/metabolismo , Simportadores/metabolismo , Fatores de Tempo
13.
Physiol Behav ; 179: 458-466, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28735060

RESUMO

Alcohol dehydrogenases (ADH) are key enzymes of ethanol metabolism that mediate its oxidation to acetaldehyde. ADHs are also able to oxidize some types of neurotransmitters such as dopamine, serotonin and norepinephrine. Increased level of ADHs activity, induced by chronic alcohol consumption, is presumably associated with disturbed neurotransmitters metabolism that leads to stable alcohol craving. As earlier reported, intraperitoneal administration of 4-methilpirasole (non-specific inhibitor of ADHs) has shown to provide a short-term anti-alcoholic effect, but individual roles of ADH isoforms in this process were still unclear. The aim of this work was to study the roles of brain and serum ADH isoforms in alcohol consumption and neurotransmitter metabolism in the rats. In the study we used specific-pathogen-free (SPF) Wistar rats chronically alcoholized with 15% ethanol. 4-methilpirasole intranasal administration in small doses led to local inhibition of ADH III activity in the brain estimated by spectrophotometric assay. It correlated with dose-dependent reduction of dopamine concentration and increased level of its metabolic products in the brain but did not influence alcohol consumption. These data allowed us to propose an important role of brain ADHs (predominantly ADH III) in metabolism of dopamine in chronically alcoholized rats but not in regulation of alcohol consumption. To evaluate the role of serum ADH isoforms we immunized the rats with recombinant horse ADH that led to production of high levels of cross-reactive anti-ADH antibodies verified by ELISA assay. Immunization led to 30% decrease in alcohol consumption and recovery of general behavioral parameters such as motor activity, anxiety and depression level. At the same time active immunization did not cause any impairments in animal blood composition. We can conclude that immunization against ADHs appeared to be a safe way to decrease alcohol consumption that could be possibly associated with neurotransmitters metabolism correction.


Assuntos
Álcool Desidrogenase/metabolismo , Consumo de Bebidas Alcoólicas/metabolismo , Encéfalo/enzimologia , Álcool Desidrogenase/antagonistas & inibidores , Álcool Desidrogenase/imunologia , Consumo de Bebidas Alcoólicas/imunologia , Consumo de Bebidas Alcoólicas/terapia , Animais , Anticorpos/metabolismo , Biomarcadores/sangue , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Fomepizol , Cavalos , Isoenzimas/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Pirazóis/farmacologia , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Reflexo de Endireitamento/efeitos dos fármacos , Reflexo de Endireitamento/fisiologia , Organismos Livres de Patógenos Específicos , Estupor/induzido quimicamente , Vacinação
14.
Br J Haematol ; 166(6): 862-74, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24942980

RESUMO

While imatinib and other tyrosine kinase inhibitors (TKIs) are highly efficacious in the treatment of chronic myeloid leukaemia (CML), some patients become refractory to these therapies. After confirming that interleukin-3 receptor (IL3R, CD123) is highly expressed on CD34(+) /CD38(-) BCR-ABL1(+) CML stem cells, we investigated whether targeting IL3R with diphtheria toxin (DT)-IL3 fusion proteins SL-401 (DT388 -IL3) and SL-501 (DT388 -IL3[K116W]) could eradicate these stem cells. SL-401 and SL-501 inhibited cell growth and induced apoptosis in the KBM5 cell line and its TKI-resistant KBM5-STI subline. Combinations of imatinib with these agents increased apoptosis in KBM5 and in primary CML cells. In six primary CML samples, including CML cells harbouring the ABL1 T315I mutation, SL-401 and SL-501 decreased the absolute numbers of viable CD34(+) /CD38(-) /CD123(+) CML progenitor cells by inducing apoptosis. IL3-targeting agents reduced clonogenic growth and diminished the fraction of primitive long-term culture-initiating cells in samples from patients with advanced phase CML that were resistant to TKIs or harboured an ABL1 mutation. Survival was also extended in a mouse model of primary TKI-resistant CML blast crisis. These data suggest that the DT-IL3 fusion proteins, SL-401 and SL-501, deplete CML stem cells and may increase the effectiveness of current CML treatment, which principally targets tumour bulk.


Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Receptores de Interleucina-3/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Leucemia Mieloide de Fase Crônica/patologia , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Piperazinas/farmacologia , Pirimidinas/farmacologia , Transplante Heterólogo , Células Tumorais Cultivadas
15.
Cancer Biol Ther ; 13(10): 858-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22785211

RESUMO

Overcoming resistance to chemotherapy is the main therapeutic challenge in the treatment of acute lymphocytic leukemia (ALL). Interactions between leukemia cells and the microenvironment promote leukemia cell survival and confer resistance to chemotherapy. Hypoxia is an integral component of bone marrow (BM) microenvironment. Hypoxia-inducible factor-1α (HIF-1), a key regulator of the cellular response to hypoxia, regulates cell growth and metabolic adaptation to hypoxia. HIF-1α expression, analyzed by Reverse Phase Protein Arrays in 92 specimens from newly diagnosed patients with pre-B-ALL, had a negative prognostic impact on survival (p = 0.0025). Inhibition of HIF-1α expression by locked mRNA antagonist (LNA) promoted chemosensitivity under hypoxic conditions, while pharmacological or genetic stabilization of HIF-1α under normoxia inhibited cell growth and reduced apoptosis induction by chemotherapeutic agents. Co-culture of pre-B ALL or REH cells with BM-derived mesenchymal stem cells (MSC) under hypoxia resulted in further induction of HIF-1α protein and acquisition of the glycolytic phenotype, in part via stroma-induced AKT/mTOR signaling. mTOR blockade with everolimus reduced HIF-1α expression, diminished glucose uptake and glycolytic rate and partially restored the chemosensitivity of ALL cells under hypoxia/stroma co-cultures. Hence, mTOR inhibition or blockade of HIF-1α-mediated signaling may play an important role in chemosensitization of ALL cells under hypoxic conditions of the BM microenvironment.


Assuntos
Medula Óssea/metabolismo , Medula Óssea/patologia , Resistencia a Medicamentos Antineoplásicos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Transdução de Sinais , Microambiente Tumoral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Criança , Pré-Escolar , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Expressão Gênica , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Lactente , Masculino , Camundongos , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Análise de Sobrevida , Serina-Treonina Quinases TOR/antagonistas & inibidores , Transplante Heterólogo , Adulto Jovem
16.
PLoS One ; 7(4): e36122, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22563443

RESUMO

Recently, we demonstrated that leaf wounding results in the synthesis of pectin methylesterase (PME), which causes the plant to release methanol into the air. Methanol emitted by a wounded plant increases the accumulation of methanol-inducible gene mRNA and enhances antibacterial resistance as well as cell-to-cell communication, which facilitates virus spreading in neighboring plants. We concluded that methanol is a signaling molecule involved in within-plant and plant-to-plant communication. Methanol is considered to be a poison in humans because of the alcohol dehydrogenase (ADH)-mediated conversion of methanol into toxic formaldehyde. However, recent data showed that methanol is a natural compound in normal, healthy humans. These data call into question whether human methanol is a metabolic waste product or whether methanol has specific function in humans. Here, to reveal human methanol-responsive genes (MRGs), we used suppression subtractive hybridization cDNA libraries of HeLa cells lacking ADH and exposed to methanol. This design allowed us to exclude genes involved in formaldehyde and formic acid detoxification from our analysis. We identified MRGs and revealed a correlation between increases in methanol content in the plasma and changes in human leukocyte MRG mRNA levels after fresh salad consumption by volunteers. Subsequently, we showed that the methanol generated by the pectin/PME complex in the gastrointestinal tract of mice induces the up- and downregulation of brain MRG mRNA. We used an adapted Y-maze to measure the locomotor behavior of the mice while breathing wounded plant vapors in two-choice assays. We showed that mice prefer the odor of methanol to other plant volatiles and that methanol changed MRG mRNA accumulation in the mouse brain.We hypothesize that the methanol emitted by wounded plants may have a role in plant-animal signaling. The known positive effect of plant food intake on human health suggests a role for physiological methanol in human gene regulation.


Assuntos
Metanol/metabolismo , Transdução de Sinais , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Animais , Encéfalo/metabolismo , Brassica rapa/enzimologia , Brassica rapa/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Regulação para Baixo , Formaldeído/metabolismo , Formiatos/metabolismo , Biblioteca Gênica , Células HeLa , Humanos , Leucócitos/metabolismo , Camundongos , Hibridização de Ácido Nucleico , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , RNA Mensageiro/metabolismo , Regulação para Cima
17.
PLoS Pathog ; 8(4): e1002640, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496658

RESUMO

Many plants release airborne volatile compounds in response to wounding due to pathogenic assault. These compounds serve as plant defenses and are involved in plant signaling. Here, we study the effects of pectin methylesterase (PME)-generated methanol release from wounded plants ("emitters") on the defensive reactions of neighboring "receiver" plants. Plant leaf wounding resulted in the synthesis of PME and a spike in methanol released into the air. Gaseous methanol or vapors from wounded PME-transgenic plants induced resistance to the bacterial pathogen Ralstonia solanacearum in the leaves of non-wounded neighboring "receiver" plants. In experiments with different volatile organic compounds, gaseous methanol was the only airborne factor that could induce antibacterial resistance in neighboring plants. In an effort to understand the mechanisms by which methanol stimulates the antibacterial resistance of "receiver" plants, we constructed forward and reverse suppression subtractive hybridization cDNA libraries from Nicotiana benthamiana plants exposed to methanol. We identified multiple methanol-inducible genes (MIGs), most of which are involved in defense or cell-to-cell trafficking. We then isolated the most affected genes for further analysis: ß-1,3-glucanase (BG), a previously unidentified gene (MIG-21), and non-cell-autonomous pathway protein (NCAPP). Experiments with Tobacco mosaic virus (TMV) and a vector encoding two tandem copies of green fluorescent protein as a tracer of cell-to-cell movement showed the increased gating capacity of plasmodesmata in the presence of BG, MIG-21, and NCAPP. The increased gating capacity is accompanied by enhanced TMV reproduction in the "receivers". Overall, our data indicate that methanol emitted by a wounded plant acts as a signal that enhances antibacterial resistance and facilitates viral spread in neighboring plants.


Assuntos
Metanol/metabolismo , Nicotiana/metabolismo , Doenças das Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Ralstonia solanacearum/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Metanol/farmacologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Plasmodesmos/genética , Plasmodesmos/metabolismo , Plasmodesmos/microbiologia , Nicotiana/genética , Nicotiana/microbiologia , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/metabolismo
18.
PLoS One ; 6(3): e17541, 2011 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-21390232

RESUMO

BACKGROUND: Plant biotechnology provides a valuable contribution to global health, in part because it can decrease the cost of pharmaceutical products. Breast cancer can now be successfully treated by a humanized monoclonal antibody (mAb), trastuzumab (Herceptin). A course of treatment, however, is expensive and requires repeated administrations of the mAb. Here we used an Agrobacterium-mediated transient expression system to produce trastuzumab in plant cells. METHODOLOGY/PRINCIPAL FINDINGS: We describe the cloning and expression of gene constructs in Nicotiana benthamiana plants using intron-optimized Tobacco mosaic virus- and Potato virus X-based vectors encoding, respectively, the heavy and light chains of trastuzumab. Full-size antibodies extracted and purified from plant tissues were tested for functionality and specificity by (i) binding to HER2/neu on the surface of a human mammary gland adenocarcinoma cell line, SK-BR-3, in fluorescence-activated cell sorting assay and (ii) testing the in vitro and in vivo inhibition of HER-2-expressing cancer cell proliferation. We show that plant-made trastuzumab (PMT) bound to the Her2/neu oncoprotein of SK-BR-3 cells and efficiently inhibited SK-BR-3 cell proliferation. Furthermore, mouse intraperitoneal PMT administration retarded the growth of xenografted tumors derived from human ovarian cancer SKOV3 Her2+ cells. CONCLUSIONS/SIGNIFICANCE: We conclude that PMT is active in suppression of cell proliferation and tumor growth.


Assuntos
Anticorpos Monoclonais/farmacologia , Neoplasias/patologia , Nicotiana/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Epitopos/imunologia , Feminino , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias Ovarianas/patologia , Peptídeos/imunologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Ligação Proteica/efeitos dos fármacos , Receptor ErbB-2/metabolismo , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Plant Mol Biol ; 74(6): 591-603, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20953971

RESUMO

The synthesis and subsequent nuclear export of non-coding RNA (ncRNA) directed by RNA polymerase (Pol) II is very sensitive to abiotic and biotic external stimuli including pathogen challenges. To assess whether stress-induced ncRNAs may suppress the nuclear export of mRNA, we exploited the ability of Agrobacterium tumefaciens to co-deliver Pol I, II and III promoter-based vectors for the transcription of short (s) ncRNAs, GFP mRNA or genomic RNA of plant viruses (Tobacco mosaic virus, TMV; or Potato virus X, PVX) into the nucleus of Nicotiana benthamiana cells. We showed that, in contrast to Pol I- and Pol III-derived sncRNAs, all tested Pol II-derived sncRNAs (U6 RNA, tRNA or artificial RNAs) resulted in decreased expression of GFP and host mRNA. The level of this inhibitory effect depended on the non-coding transcript length and promoter strength. Short coding RNA (scRNA) can also compete with mRNA for nuclear export. We showed that scRNA, an artificial 117-nt short sequence encoding Elastin-Like peptide element tandems with FLAG sequence (ELF) and the 318-nt N. benthamiana antimicrobial peptide thionin (defensin) gene efficiently decreased GFP expression. The stress-induced export of Pol II-derived sncRNA and scRNA into the cytoplasm via the mRNA export pathway may block nucleocytoplasmic traffic including the export of mRNA responsible for antivirus protection. Consistent with this model, we observed that Pol II-derived sncRNAs as well as scRNA, thionin and ELF strongly enhanced the cytoplasmic reproduction of TMV and PVX RNA.


Assuntos
Núcleo Celular/metabolismo , Nicotiana/genética , RNA Polimerase II/fisiologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Transporte Ativo do Núcleo Celular , Transporte Biológico , Citoplasma/metabolismo , Proteínas de Fluorescência Verde/análise , Potexvirus/genética , RNA Interferente Pequeno/análise , Pequeno RNA não Traduzido/análise , Pequeno RNA não Traduzido/fisiologia , RNA Viral/metabolismo , Vírus do Mosaico do Tabaco/genética
20.
Virology ; 407(1): 7-13, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-20801474

RESUMO

Human epidermal growth factor receptor-2 (HER2/neu) is a target for the humanized monoclonal antibody trastuzumab. Recently, trastuzumab-binding peptides (TBP) of HER2/neu that inhibit proliferation of breast cancer cells were identified. We have now studied conditions of efficient assembly in vivo of Tobacco mosaic virus (TMV)-based particles displaying TBP on its surface. The system is based on an Agrobacterium-mediated co-delivery of binary vectors encoding TMV RNA and coat protein (CP) with TBP in its C-terminal extension into plant leaves. We show how the fusion of amino acid substituted TBP (sTBP) to CP via a flexible peptide linker can improve the manufacturability of recombinant TMV (rTMV). We also reveal that rTMV particles with exposed sTBP retained trastuzumab-binding capacity but lost an anti-HER2/neu immunogenic scaffold function. Mouse antibodies against rTMV did not recognize HER2/neu on surface of human SK-BR-3 cells.


Assuntos
Anticorpos Monoclonais/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Vírus do Mosaico do Tabaco/genética , Vírus do Mosaico do Tabaco/metabolismo , Anticorpos Monoclonais Humanizados , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Vetores Genéticos , Humanos , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Rhizobium/genética , Trastuzumab
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