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1.
Biochem Biophys Res Commun ; 722: 150154, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38795456

RESUMEN

Azospirillum brasilense is a non-photosynthetic α-Proteobacteria, belongs to the family of Rhodospirillaceae and produces carotenoids to protect itself from photooxidative stress. In this study, we have used Resonance Raman Spectra to show similarity of bacterioruberins of Halobacterium salinarum to that of A. brasilense Cd. To navigate the role of genes involved in carotenoid biosynthesis, we used mutational analysis to inactivate putative genes predicted to be involved in carotenoid biosynthesis in A. brasilense Cd. We have shown that HpnCED enzymes are involved in the biosynthesis of squalene (C30), which is required for the synthesis of carotenoids in A. brasilense Cd. We also found that CrtI and CrtP desaturases were involved in the transformation of colorless squalene into the pink-pigmented carotenoids. This study elucidates role of some genes which constitute very pivotal role in biosynthetic pathway of carotenoid in A. brasilense Cd.


Asunto(s)
Azospirillum brasilense , Carotenoides , Escualeno , Carotenoides/metabolismo , Azospirillum brasilense/metabolismo , Azospirillum brasilense/genética , Escualeno/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Vías Biosintéticas , Espectrometría Raman
2.
Ann Afr Med ; 22(4): 446-450, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38358144

RESUMEN

Background: Aplastic anemia (AA) is an uncommon condition characterized by pancytopenia and hypocellular bone marrow. Interleukin (IL)-6 and IL-8 have been shown to inhibit myelopoiesis and are major mediators of tissue damage. The primary goal of this study was to determine the IL-6 and IL-8 levels in children with AA, as well as their relationship to illness severity and immunosuppressive medication response. Materials and Methods: The IL-6 and IL-8 levels were tested in 50 children aged 3-18 years who had AA. As controls, 50 healthy age and sex matched individuals were used. A sandwich enzyme-linked immunosorbent assay kit (solid-phase) was used to measure IL-6 and IL-8 levels quantitatively. The concentrations of IL-6 and IL-8 in pg/mL were used to represent the results. Immunosuppressive medication was given to the patients in accordance with the British Committee for Standards in Haematology Guidelines 2009. Results: The patients' average age was 11.3 ± 3.7 years. Patients with AA had significantly higher IL-6 and IL-8 levels than controls (278.88 ± 216.03 vs. 4.51 ± 3.26; P < 0.001) and (120.28 ± 94.98 vs. 1.79 ± 0.78; P < 0.001), respectively. The IL-6 and IL-8 levels were also investigated with respect to AA severity, with statistically significant differences (P < 0.01) between different grading strata. Patients with very severe AA (VSAA) had the highest IL-6 levels (499.52 ± 66.19), followed by severe AA (SAA) (201.28 ± 157.77) and non-SAA (NSAA) (22.62 ± 14.63). For IL-8 levels, a similar trend (P < 0.01) was detected, with values of 209.81 ± 38.85, 92.12 ± 78.0, and 9.29 ± 10.68 for VSAA, SAA, and NSAA, respectively. After 6 months of immunosuppressive treatment (IST), mean levels of IL-6 and IL-8 in responders and nonresponders were again assessed. The mean IL-6 level in the responders' group (46.50 ± 45.41) was significantly lower, when compared to the nonresponders' group (145.76 ± 116.32) (P < 0.001). Similarly, the mean IL-8 level in the responder's group (33.57 ± 27.14) was significantly lower, compared to the nonresponder's group (97.49 ± 69.00) (P < 0.001). Conclusions: Children with AA had higher IL-6 and IL-8 levels than normal age- and sex-matched controls. Increased levels were linked to the severity of the condition, suggesting that IL may have a role in AA. IL levels can be monitored in AA patients during IST, which can assist in predicting response to IST.


Résumé Contexte: L'anémie aplastique (AA) est une affection peu fréquente caractérisée par une pancytopénie et une moelle osseuse hypocellulaire. Il a été démontré que l'interleukine (IL)-6 et l'IL-8 inhibent la myélopoïèse et sont des médiateurs majeurs des lésions tissulaires. L'objectif principal de cette étude était de déterminer les niveaux d'IL-6 et d'IL-8 chez les enfants atteints d'AA, ainsi que leur relation avec la gravité de la maladie et la réponse aux médicaments immunosuppresseurs. Matériel et méthodes: Les niveaux d'IL-6 et d'IL-8 ont été testés chez 50 enfants âgés de 3 à 18 ans atteints d'AA. 50 témoins sains appariés par l'âge et le sexe ont été utilisés. Un kit de dosage immuno-enzymatique en sandwich (phase solide) a été utilisé pour mesurer quantitativement les niveaux d'IL-6 et d'IL-8. de manière quantitative. Les concentrations d'IL-6 et d'IL-8 en pg/mL ont été utilisées pour représenter les résultats. Des médicaments immunosuppresseurs ont été administrés aux patients conformément aux directives 2009 du British Committee for Standards in Haematology. Résultats: L'âge moyen des patients était de 11,3 ± 3,7 ans. Les patients atteints d'AA présentaient des taux d'IL-6 et d'IL-8 significativement plus élevés que les témoins (278,88 ± 216,03 contre 4,51 ± 3,26 ; P < 0,001) et (120,28 ± 94,98 contre 1,79 ± 0,78 ; P < 0,001), respectivement. Les taux d'IL-6 et d'IL-8 ont également été étudiés en fonction de la gravité de l'AA, avec des différences statistiquement significatives (P < 0,01) entre les différentes strates de classement. Les patients présentant une AA très sévère (VSAA) avaient les taux d'IL-6 les plus élevés (499,52 ± 66,19), suivis par les patients atteints d'AA sévère (SAA) (201,28 ± 157,77) et les patients non-SAA (NSAA) (22,62 ± 14,63). Pour les niveaux d'IL-8, une tendance similaire (P < 0,01) a été détectée, avec des valeurs de 209,81 ± 38,85, 92,12 ± 78,0, et 9,29 ± 10,68 pour les VSAA, SAA et NSAA, respectivement. Après 6 mois de traitement immunosuppresseur traitement immunosuppresseur (IST), les niveaux moyens d'IL-6 et d'IL-8 chez les répondeurs et les non-répondeurs ont été à nouveau évalués. Le taux moyen d'IL-6 dans le groupe des répondeurs (46,50 ± 45,41) était significativement plus faible, par rapport au groupe des non-répondeurs (145,76 ± 116,32) (P < 0,001). De même, le niveau moyen d'IL-8 dans le groupe des répondeurs (33,57 ± 27,14) était significativement plus faible que dans le groupe des non-répondeurs (97,49 ± 69,00) (P < 0,001). Conclusions: Les enfants atteints d'AA présentaient des niveaux d'IL-6 et d'IL-8 plus élevés que les témoins normaux appariés selon l'âge et le sexe. L'augmentation des taux était liée à la gravité de l'affection, suggérant que l'IL pourrait jouer un rôle dans l'AA. Les niveaux d'IL peuvent être surveillés chez les patients atteints d'AA pendant l'IST, ce qui peut aider à prédire la réponse à l'IST. Mots-clés: Anémie aplastique, traitement immunosuppresseur, interleukine-6, interleukine-8.


Asunto(s)
Anemia Aplásica , Niño , Humanos , Adolescente , Anemia Aplásica/tratamiento farmacológico , Interleucina-6/uso terapéutico , Interleucina-8/uso terapéutico , Resultado del Tratamiento , Inmunosupresores/uso terapéutico , Terapia de Inmunosupresión , Gravedad del Paciente
3.
Appl Microbiol Biotechnol ; 106(23): 7891-7903, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36334127

RESUMEN

Bacteria of the genus Azospirillum include several plant associated bacteria which often promote the growth of their host plants. Although the host range of Azospirillum brasilense Sp7 is much wider than its close relative Azospirillum lipoferum 4B, it lacks the ability to efficiently utilize D-glucose for its growth. By comparing the genomes of both the species, the genes of A. lipoferum 4B responsible for conferring D-glucose utilization ability in A. brasilese Sp7 were identified by cloning individual or a combination of genes in a broad host range expression vector, mobilizing them in A. brasilense Sp7 and examining the ability of exconjugants to use D-glucose as sole carbon source for growth. These genes also included the homologs of genes involved in N-acetyl glucosamine utilization in Pseudomonas aeruginosa PAO1. A transcriptional fusion of the 5 genes encoding glucose-6-phosphate dehydrogenase and 4 components of glucose phosphotransferase system were able to improve D-glucose utilization ability in A. brasilense Sp7. The A. brasilense Sp7 strain engineered with D-glucose utilization ability showed significantly improved root colonization of rice seedling. The improvement in the ability of A. brasilense Sp7 to colonize rice roots is expected to bring benefits to rice by promoting its growth. KEY POINTS: • Genes required for glucose utilization in Azospirillum lipoferum were identified. • A gene cassette encoding glucose utilization was constructed. • Transfer of gene cassette in A. brasilense improves glucose utilization and rice root colonization..


Asunto(s)
Azospirillum brasilense , Azospirillum , Oryza , Azospirillum brasilense/genética , Azospirillum brasilense/metabolismo , Glucosa/metabolismo
4.
Asian J Transfus Sci ; 16(1): 95-98, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36199407

RESUMEN

INTRODUCTION: Thrombopoietin (TPO) being the major regulator of megakaryopoiesis is expected to show a compensatory increase in immune thrombocytopenia (ITP), however, it is not so observed. This study was undertaken to measure TPO levels in ITP and assesses its association with platelet count, megakaryocytes, and response to steroid therapy. MATERIALS AND METHODS: A total of 41 cases of ITP and twenty controls with normal platelet count were enrolled in this prospective study. Complete blood count, bone marrow examination, and ELISA for serum TPO were measured. Response to steroid therapy was evaluated for thirty cases. RESULTS: The TPO levels were increased in 80.5% of patients in comparison to the controls. The degree of rise, however, was variable. On analyzing low, normal, and high TPO levels with reference to platelet and megakaryocyte count no statistically significant difference was observed. Raised TPO levels were seen with significant lowering of functional megakaryocytes. The mean TPO levels in nonresponders were higher than responders but highly variable and statistically nonsignificant. CONCLUSION: Quantitative alterations in TPO are in a way regulated by qualitative efficacy of megakaryocytes rather than platelet or megakaryocyte count. Nonresponders with markedly increased TPO levels (due to qualitative megakaryocyte injury) are less likely to respond to TPO receptor agonist.

5.
J Med Life ; 15(5): 606-616, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35815090

RESUMEN

Blast crisis (BC) is an outcome that arises during the treatment process of chronic myeloid leukemia (CML), which is possibly attained by the dysregulation of the Notch and Ikaros signaling pathways, BCR-ABL translocation, redox, and inflammatory factors. This study demonstrated that biotherapeutic agents target aberrant molecular axis in CML-BC cells. The HALOA complex was synthesized by simple mixing of apo α-lactalbumin with oleic acid, which manages to inhibit BCR-ABL (b3a2 in K562 cells) translocation. It elevates the production of reactive oxygen species (ROS), reactive nitrogen species (RNS), and protein carbonyl, which induces DNA fragmentation in K562 cells but not in NIH cells. The complex manages to reduce the toxicity surrounding apoptotic cells by enhancing the production of superoxide dismutase (SOD) and the total antioxidant level. The HALOA complex increases leptin to maintain normoxic conditions, ultimately preventing angiogenesis. This complex downregulates the expression of IL-8 and MMP-9 and elevates the expression levels of Notch 4, Ikaros, and integrin alpha-D/CD-11d (tumor-suppressive), which conjointly prevents inflammation, metastasis, and epithelial-mesenchymal transition (EMT) in CML cells. Meanwhile, the complex downregulates Notch 1 and 2 (oncogenic), consequently inducing anoikis in CML cells. Overall, the HALOA complex shows credibility by targeting the combined molecular factors responsible for the pathogenesis of the disease and will also help to overcome MDR conditions in leukemia.


Asunto(s)
Proteínas de Fusión bcr-abl , Leucemia Mielógena Crónica BCR-ABL Positiva , Anoicis , Apoptosis , Crisis Blástica/genética , Crisis Blástica/metabolismo , Crisis Blástica/patología , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/metabolismo , Proteínas de Fusión bcr-abl/uso terapéutico , Humanos , Inflamación , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Oxidación-Reducción
6.
Front Oncol ; 12: 912942, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847841

RESUMEN

Chronic myeloid leukemia (CML) is potentially fatal blood cancer, but there is an unmet need to discover novel molecular biomarkers. The hypothesis of this study aimed to elucidate the relationship of HIF1α with the redox system, Krebs cycles, notch1, and other regulatory proteins to better understand the pathophysiology and clinical relevance in chronic myeloid leukemia (CML) patients, as the molecular mechanism of this axis is still not clear. This study included CML patient samples (n = 60; 60: blood; 10: bone marrow tissues) and compared them with healthy controls (n = 20; blood). Clinical diagnosis confirmed on bone marrow aspiration, marrow trephine biopsy, and BCR/ABL1 translocation. Cases were subclassified into chronic, accelerated, and blast crises as per WHO guidelines. Molecular experiments included redox parameters, DNA fragmentation, Krebs cycle metabolites, and gene expression by RT-PCR/Western blot/LC-MS, PPI (STRING), Pearson correlation, and ROC curve analysis. Here, our findings show that p210/p190BCR/ABL1 translocation is common in all blast crisis phases of CML. Redox factor/Krebs oncometabolite concentrations were high, leading to upregulation and stabilization of HIF1α. HIF1α leads to the pathogenesis in CML cells by upregulating their downstream genes (Notch 2/4/Ikaros/SIRT1/Foxo-3a/p53, etc.). Whereas, downregulated ubiquitin proteasomal and apoptotic factors in CML pateints, can trigger degradation of HIF1α through proline hydroxylation. However, HIF1α showed a negative corelation with the notch1 pathway. Notch1 plays a tumor-suppressive role in CML and might have the potential to be used as a diagnostic marker along with other factors in CML patients. The outcome also revealed that oxidant treatment could not be effective in augmentation with conventional therapy because CML cells can enhance the levels of antioxidants for their survival. HIF1α might be a novel therapeutic target other than BCR/ABL1 translocation.

7.
Indian J Tuberc ; 69(3): 354-358, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35760486

RESUMEN

JAK 2 inhibitors are widely used for the treatment of primary myelofibrosis. Ruxolitinib is the most commonly used JAK inhibitor in clinical practice. We report two cases of Primary Myelofibrosis who developed tuberculosis on active treatment with ruxolitinib. Our first case was a 48 year male who developed disseminated tuberculosis during fourth month of treatment and second case was a 50 year male developing tubercular lymphadenitis during second month of treatment respectively. These case reports indicate reactivation of underling tubercular infection as a very dreaded complication of this treatment. The prevalence of tuberculosis is much higher in India compared to the west. A thorough pretreatment evaluation should ideally be done using Mantoux test or interferon gamma release assay (IGRA) to rule out latent tuberculosis. Furthermore, the patients should be counselled regarding the possibility of reactivation of infections including tuberculosis. Also, proper follow up is the need of hour in all patients on any kind of immunomodulators.


Asunto(s)
Tuberculosis Latente , Mielofibrosis Primaria , Tuberculosis Miliar , Humanos , Ensayos de Liberación de Interferón gamma , Tuberculosis Latente/epidemiología , Masculino , Nitrilos , Mielofibrosis Primaria/tratamiento farmacológico , Pirazoles , Pirimidinas/uso terapéutico , Prueba de Tuberculina , Tuberculosis Miliar/complicaciones
8.
Proteins ; 90(11): 1926-1943, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35579112

RESUMEN

In Azospirillum brasilense, an extra-cytoplasmic function σ factor (RpoE10) shows the characteristic 119 amino acid long C-terminal extension found in ECF41-type σ factors, which possesses three conserved motifs (WLPEP, DGGGR, and NPDKV), one in the linker region between the σ2 and σ4 , and the other two in the SnoaL_2 domain of the C-terminal extension. Here, we have described the role of the two conserved motifs in the SnoaL_2 domain of RpoE10 in the inhibition and activation of its activity, respectively. Truncation of the distal part of the C-terminal sequence of the RpoE10 (including NPDKV but excluding the DGGGR motif) results in its promoter's activation suggesting autoregulation. Further truncation of the C-terminal sequence up to its proximal part, including NPDKV and DGGGR motif, abolished promoter activation. Replacement of NPDKV motif with NAAAV in RpoE10 increased its ability to activate its promoter, whereas replacement of DGGGR motif led to reduced promoter activation. We have explored the dynamic modulation of σ2 -σ4 domains and the relevant molecular interactions mediated by the two conserved motifs of the SnoaL2 domain using molecular dynamics simulation. The analysis enabled us to explain that the NPDKV motif located distally in the C-terminus negatively impacts transcriptional activation. In contrast, the DGGGR motif found proximally of the C-terminal extension is required to activate RpoE10.


Asunto(s)
Azospirillum brasilense , Factor sigma , Aminoácidos/metabolismo , Azospirillum brasilense/genética , Azospirillum brasilense/metabolismo , Proteínas Bacterianas/química , Regulación Bacteriana de la Expresión Génica , Homeostasis , Factor sigma/química
9.
Nutr Cancer ; 74(10): 3527-3532, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35594251

RESUMEN

Vitamin D deficiency(<20 ng/mL) is a common condition, associated with an inferior prognosis in some cancers. However, the prognostic significance of vitamin D deficiency in acute leukemia is largely unknown. The present study aimed to assess the baseline status of vitamin D [25-(OH) D3] and find its association with induction remission rate and mortality using standard chemotherapy in patients with acute leukemia. In this prospective observational study, blood samples were collected from 73 newly diagnosed patients before starting induction chemotherapy to measure serum vitamin D [25(OH)D] levels along with routine investigations.44/73 (60.3%) patients were acute lymphoblastic leukemia (ALL), and 29/77 (39.7%) were acute myeloid leukemia (AML) patients. Descriptive statistics and frequency distribution were used in SPSS software, and Pearson's chi-squared test compared the categorical variables. Post-induction remission status (complete and incomplete remission) and induction-related mortality were correlated with vitamin D levels. 44/73 patients (60.3%) included in this study were males, and the remaining were females. The mean age of the participants was 30.32 ± 14.95 years. The mean serum vitamin D level in the cohort was 15.74 ± 28.14 ng/mL. Vitamin D deficiency was observed in 59/73 (80.8%) patients, whereas 14/73 (19.2%) had normal levels (≥20ng/mL) of the vitamin. Vitamin D deficiency is common among acute leukemia patients. Herein, we observed that low vitamin D level is associated with higher rates of incomplete remission in acute leukemia patients (P = 0.016). Vitamin D deficiency is common among acute leukemia patients and is associated with poor short-term outcomes.


Asunto(s)
Leucemia Mieloide Aguda , Deficiencia de Vitamina D , Adolescente , Adulto , Calcifediol , Femenino , Humanos , Quimioterapia de Inducción , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Vitamina D , Adulto Joven
10.
J Supercomput ; 78(13): 14813-14845, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431450

RESUMEN

In this work, we propose a multi-tier architectural model to separate functionality and security concerns for distributed cyber-physical systems. On the line of distributed computing, such systems require the identification of leaders for distribution of work, aggregation of results, etc. Further, we propose a fault-tolerant leader election algorithm that can independently elect the functionality and security leaders. The proposed election algorithm identifies a list of potential leader capable nodes to reduce the leader election overhead. It keeps identifying the highest potential node as the leader, whenever needed, including the situation when one has failed. We also explain the proposed architecture and its management method through a case study. Further, we perform several experiments to evaluate the system performance. The experimental results show that the proposed architectural model improves the system performance in terms of latency, average response time, and the number of real-time tasks completed within the deadline.

11.
Discoveries (Craiova) ; 10(4): e157, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37483535

RESUMEN

INTRODUCTION AND AIMS: Aplastic anemia is a rare, fatal bone marrow disorder that is presumed to be an autoimmune-mediated illness that actively destroys haematopoietic cells through a T helper type-1 cell response. Different cell types in the bone marrow and peripheral circulation produce chemokines, such as interleukin-6 (IL-6) and interleukin-8 (IL-8). The myelopoiesis that is profoundly impaired in aplastic anemia may be inhibited by these two, as critical and powerful inhibitors. Therefore, it is conceivable that their ongoing overproduction may contribute to aplastic anemia. We performed a quantitative enzyme-linked immunosorbent assay on the peripheral blood plasma to reveal the levels of IL-6 and IL-8 and their correlation to aplastic anaemia. MATERIALS AND METHODS: A total of 80 cases of aplastic anemia were included in this study, diagnosed according to the criteria laid down by the International Agranulocytosis and Aplastic Anemia study group. A total of 10 healthy individuals served as controls in this study. With the help of a commercial ELISA kit and the instructions from the kit's maker, the levels of IL-6 and IL-8 were measured in a quantitative way. RESULTS: Mean serum IL-6 and IL-8 levels in cases were 283.28±220.27 and 122.56±97.79 pg/ml, respectively, as compared to 7.52±1.43 and 3.42±1.73 pg/ml levels in controls. Statistically, mean IL-6, as well as IL-8 levels, were significantly higher in aplastic anemia patients than in controls (p< 0.001). Levels of interleukins were also assessed in relation to the severity of the disease. Patients with very severe aplastic anaemia had significantly higher mean IL-6 and IL-8 levels (516.71±36.73 and 220.50±23.45 pg/ml, respectively), followed by severe aplastic anaemia (198.84±150.39 and 89.82±77.18 pg/ml, respectively) and non-severe aplastic anaemia (26.71±33.40 and 10.29±2.63 pg/ml, respectively) (p<0.001). CONCLUSION: Blood serum levels of IL-6 and IL-8 were increased in aplastic anemia and showed a correlation with the severity of the disease. Hence, IL-6 and IL-8 may play an important role in the immune-mediated pathophysiology of aplastic anemia and their increasing levels are giving alarming signals for timely implementation of the appropriate treatment regimen to stop further progression of the disease. Additional studies are required in order to further investigate the exact involvement and role of IL-6 and IL-8 in aplastic anemia.

12.
Indian J Hematol Blood Transfus ; 37(4): 563-568, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34744340

RESUMEN

T cells in B chronic lymphocytic leukaemia (CLL) have been reported to show qualitative and quantitative alterations, thereby regulating the antitumor immune response. We evaluated the absolute count, percentages of T cells and subsets and their association with disease parameters in Indian patients. 45 treatment naïve CLL cases and 10 healthy controls were evaluated for CD3 + Tcells, CD4 + T cells, CD8 + T cells percentage by flowcytometry. The absolute counts were obtained by multiplication with absolute lymphocyte counts obtained on cell counter. The clinical characteristics (age, sex, Rai stage, B symptoms, CD38 expression) were analysed for any association with alteration of these cells (percentages, absolute counts, ratio with monoclonal B cell count) and CD4: CD8 ratio. The mean absolute count of CD3 + T cell, CD4 + T cell and CD8 + T cells was significantly higher (p < 0.05) in CLL patients as compared to healthy controls. CD4:CD8 ratio was variable (normal, increased and decreased). The mean CD8 + T cells count was higher in advanced disease stage, and CD38 positive cases (p > 0.05). Younger CLL patients (< 55 years) had greater increase in CD8 + T cells (p > 0.05). Significant alterations in T cells and their subsets were observed in CLL. A trend towards advanced stage, CD38 expression, presentation an early age was seen with increase in CD8 + T cell counts.

13.
J Bacteriol ; 203(24): e0026921, 2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34570625

RESUMEN

Azospirillum brasilense is a plant growth-promoting rhizobacterium that is not known to utilize ethanol as a sole source of carbon for growth. This study shows that A. brasilense can cometabolize ethanol in medium containing fructose or glycerol as a carbon source and contribute to its growth. In minimal medium containing fructose or glycerol as a carbon source, supplementation of ethanol caused enhanced production of an alcohol dehydrogenase (ExaA) and an aldehyde dehydrogenase (AldA) in A. brasilense. However, this was not the case when malate was used as a carbon source. Inactivation of aldA in A. brasilense resulted in the loss of the AldA protein and its ethanol utilizing ability in fructose- or glycerol-supplemented medium. Furthermore, ethanol inhibited the growth of the aldA::Km mutant. The exaA::Km mutant also lost its ability to utilize ethanol in fructose-supplemented medium. However, in glycerol-supplemented medium, A. brasilense utilized ethanol due to the synthesis of a new paralog of alcohol dehydrogenase (ExaA1). The expression of exaA1 was induced by glycerol but not by fructose. Unlike exaA, expression of aldA and exaA1 were not dependent on σ54. Instead, they were negatively regulated by the RpoH2 sigma factor. Inactivation of rpoH2 in A. brasilense conferred the ability to use ethanol as a carbon source without or with malate, overcoming catabolite repression caused by malate. This is the first study showing the role of glycerol and fructose in facilitating cometabolism of ethanol by inducing the expression of ethanol-oxidizing enzymes and the role of RpoH2 in repressing them. IMPORTANCE This study unraveled a hidden ability of Azospirillum brasilense to utilize ethanol as a secondary source of carbon when fructose or glycerol were used as a primary growth substrate. It opens the possibility of studying the regulation of expression of the ethanol oxidation pathway for generating high yielding strains that can efficiently utilize ethanol. Such strains would be useful for economical production of secondary metabolites by A. brasilense in fermenters. The ability of A. brasilense to utilize ethanol might be beneficial to the host plant under the submerged growth conditions.


Asunto(s)
Azospirillum brasilense/metabolismo , Proteínas Bacterianas/metabolismo , Etanol/metabolismo , Fructosa/farmacología , Glicerol/farmacología , Factores de Transcripción/metabolismo , Proteínas Bacterianas/genética , Medios de Cultivo , Fructosa/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/fisiología , Glicerol/metabolismo , Factores de Transcripción/genética , Regulación hacia Arriba
14.
Res Microbiol ; 172(6): 103875, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34461275

RESUMEN

Fasciclin domain proteins (FDP) are found in all domains of life, but their biological role and regulation are not clearly understood. While studying the proteome of a mutant (Car1) of Azospirillum brasilense Sp7 with a Tn5 insertion in the gene encoding an anti-sigma factor (ChrR1), we found that FDP was maximally expressed. To study the biological role of this FDP, we inactivated fdp in A. brasilense Sp7 and in its Car1 mutant, which rendered them sensitive to methylene blue (MB) and toluidine blue (TB) in the presence of light. The transcription of fdp was also strongly upregulated by an ECF sigma factor (RpoE1) and photooxidative stress. The fdp null mutants of A. brasilense Sp7 and its Car1 mutant produced relatively fewer carotenoids and showed reduced flocculation. The reduced ability of fdp null mutants to flocculate was partly due to their reduced ability to produce carotenoids as inhibition of carotenoid synthesis by diphenylamine reduced their flocculation ability by 15-20%. Hence, FDP plays an important role in protecting A. brasilense Sp7 against photo-oxidative stress by supporting carotenoid accumulation and cell aggregation.


Asunto(s)
Azospirillum brasilense/fisiología , Proteínas Bacterianas/metabolismo , Luz , Proteínas de la Membrana/metabolismo , Estrés Oxidativo , Azospirillum brasilense/genética , Azospirillum brasilense/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Carotenoides/metabolismo , Biología Computacional , Floculación , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Filogenia , Dominios Proteicos , Factor sigma/genética , Factor sigma/metabolismo
15.
Indian J Hematol Blood Transfus ; 37(3): 372-378, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34267454

RESUMEN

Epstein Barr virus (EBV) associated Hodgkin lymphoma (HL) has been defined as cases with clonal EBV infection, EBV genome and gene products in the Reed Sternberg cells. We evaluated the prevalence and clinico-pathological association of EBV in North Indian HL patients. Eighty-eight cases of histologically confirmed classic HL were evaluated for EBV by both IHC expression of LMP1 and real time PCR on formalin fixed lymph node tissue. The expression pattern was analyzed for any association with clinical and histomorphological parameters. Nodular sclerosis subtype was seen in 79.5% patients and mixed cellularity was seen in the remaining patients. Ninety percent of the cases were positive for EBV. The detection rate of EBV by IHC was higher. The EBV positive cases presented with higher disease stage (p < 0.05). The presence of histomorphological features like granuloma formation (5/5), atypical lymphocytes (8/8), histiocyte clusters (26/28), large area of necrosis (11/12), less prominent inflammatory response (25/27) was associated with EBV positivity (p > 0.05). In our study population a high proportion of HL cases showed positivity for EBV indicating a pathogenic role. The positivity was independent of age, gender and histological subtype. Further evaluation of EBV positivity in modulation of tumor immunity may provide insights into variable treatment outcome in EBV positive cases.

16.
Indian J Tuberc ; 68(3): 412-415, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34099212

RESUMEN

Current standard of care for treatment of CML is based on tyrosine kinase inhibitors (TKI's). Imatinib is most frequently used first line tyrosine kinase inhibitor. Various side effects of TKI's are known, but some may still be unknown. We are reporting three cases of CML who developed tuberculosis while on treatment with imatinib or dasatinib. Two cases developed CNS tuberculosis and other one was tubercular pleural effusion. These cases indicate that imatinib and other TKI's probably interfere with immunological functions and predispose patients for tuberculosis.


Asunto(s)
Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva , Mycobacterium tuberculosis/aislamiento & purificación , Derrame Pleural , Tuberculosis del Sistema Nervioso Central , Tuberculosis Pleural , Adulto , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Causalidad , Dasatinib/administración & dosificación , Sustitución de Medicamentos , Humanos , Mesilato de Imatinib/administración & dosificación , Mesilato de Imatinib/efectos adversos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/fisiopatología , Masculino , Persona de Mediana Edad , Derrame Pleural/tratamiento farmacológico , Derrame Pleural/etiología , Derrame Pleural/microbiología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Resultado del Tratamiento , Tuberculosis del Sistema Nervioso Central/diagnóstico , Tuberculosis del Sistema Nervioso Central/tratamiento farmacológico , Tuberculosis del Sistema Nervioso Central/etiología , Tuberculosis del Sistema Nervioso Central/fisiopatología , Tuberculosis Pleural/complicaciones , Tuberculosis Pleural/diagnóstico , Tuberculosis Pleural/tratamiento farmacológico , Tuberculosis Pleural/fisiopatología
17.
Indian J Hematol Blood Transfus ; 37(2): 210-219, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33867726

RESUMEN

Aplastic anemia (AA) is an immune-mediated disorder in which hematopoietic stem and progenitor cells are targeted by a number of cellular and molecular pathways. This case control study aims to investigate the association of interleukin-1beta (IL-1ß) gene polymorphisms, (IL-1ß-31, IL-1ß-511 and IL-1ß-3954) and their plasma levels with acquired AA. Genotyping was done by Restricted Fragment Length Polymorphism (PCR-RFLP) method and IL-1ß plasma levels were evaluated in peripheral blood using ELISA. Increased level of IL-1ß was reported to be significant in cases as compared to controls. The susceptibility of developing AA was higher in the cases for IL-1ß-3954 genotype. IL-1ß-511 genotype showed significant association with the severity groups of AA. No significant association was noticed in responder versus non-responder group. Plasma level of IL-1ß gene was found to be significantly higher in severe and very-severe group of AA versus control group. Our findings suggest that IL-1ß gene and its genotypes might be involved in the pathophysiology of AA and play a central role in the etiopathogenesis of AA.

18.
J Leukoc Biol ; 110(5): 853-866, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33527482

RESUMEN

Chronic myeloid leukemia (CML) is characterized by constitutive BCR-ABL kinase activity, an aggressive proliferation of immature cells, and reduced differentiation. Targeting tyrosine kinase activity of BCR-ABL with imatinib is an effective therapy for the newly diagnosed CML patients; however, 20%-30% of the patients initially treated with imatinib eventually experience treatment failure. Therefore, early identification of these patients is of high clinical relevance. In the present study, we by undertaking a direct comparison of inducible NOS (iNOS) status in neutrophils from healthy volunteers, newly diagnosed, imatinib responder, and resistant CML patients as well as by conducting in vitro studies in K562 cells demonstrated that inhibition of BCR-ABL by imatinib or siRNA significantly enhanced NO generation and iNOS expression. Indeed, patients exhibiting treatment failure or imatinib resistance were less likely to induce NO generation/iNOS expression. Our findings further demonstrated that imatinib mediated antiproliferative and proapoptotic effect in BCR-ABL+ cells associated with enhanced iNOS expression, and it was significantly prevented in the presence of L-NAME, 1400W, or iNOS siRNA. Overexpression of iNOS in K562 cells expectedly enhanced imatinib sensitivity on cytostasis and apoptosis, even at lower concentration (0.1 µM) of imatinib. Mechanistically, imatinib or BCR-ABL siRNA following deglutathionylation of NF-κB, enhanced its binding to iNOS promoter and induced iNOS transcription. Deglutathionylation of procaspase-3 however associated with increased caspase-3 activity and cell apoptosis. Taken together, results obtained suggest that monitoring NO/iNOS level could be useful to identify patients likely to be responsive or resistant to imatinib and can be used to personalized alternative therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/fisiología , Mesilato de Imatinib/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Óxido Nítrico Sintasa de Tipo II/metabolismo , Adolescente , Adulto , Anciano , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Femenino , Proteínas de Fusión bcr-abl/genética , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/enzimología , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Adulto Joven
19.
Mol Cancer Res ; 19(2): 261-273, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33188146

RESUMEN

Glycogen synthase kinase 3ß (GSK3ß), an ubiquitously expressed serine/threonine kinase is reported to be overexpressed and hyperactivated in cancers including acute myeloid leukemia (AML) where it promotes self-renewal, growth, and survival of AML cells. Therefore, GSK3ß inhibition results in AML cell growth inhibition and myeloid differentiation. Here we identified master transcription factor PU.1 of monocyte-macrophage differentiation pathway as potential GSK3ß target. We demonstrate that GSK3ß phosphorylates PU.1 at Ser41 and Ser140 leading to its recognition and subsequent ubiquitin-mediated degradation by E3 ubiquitin ligase FBW7. This GSK3-dependent degradation of PU.1 by FBW7 inhibited monocyte-macrophage differentiation. We further showed that a phospho-deficient PU.1 mutant (PU.1-S41, S140A) neither bound to FBW7 nor was degraded by it. Consequently, PU.1-S41, S140A retained its transactivation, DNA-binding ability and promoted monocyte-macrophage differentiation of U937 cells even without phorbol 12-myristate 13-acetate (PMA) treatment. We further showed that FBW7 overexpression inhibited both PMA as well as M-CSF-induced macrophage differentiation of myeloid cell lines and peripheral blood mononuclear cells (PBMC) from healthy volunteers, respectively. Contrarily, FBW7 depletion promoted differentiation of these cells even without any inducer suggesting for a robust role of GSK3ß-FBW7 axis in negatively regulating myeloid differentiation. Furthermore, we also recapitulated these findings in PBMCs isolated from patients with leukemia where FBW7 overexpression markedly inhibited endogenous PU.1 protein levels. In addition, PBMCs also showed enhanced differentiation when treated with M-CSF and GSK3 inhibitor (SB216763) together compared with M-CSF treatment alone. IMPLICATIONS: Our data demonstrate a plausible mechanism behind PU.1 restoration and induction of myeloid differentiation upon GSK3ß inhibition and further substantiates potential of GSK3ß as a therapeutic target in AML.


Asunto(s)
Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Leucemia Mieloide Aguda/genética , Ubiquitinación/genética , Animales , Diferenciación Celular , Humanos , Leucemia Mieloide Aguda/patología , Ratones , Fosforilación , Transfección
20.
J Med Life ; 14(5): 620-635, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35027964

RESUMEN

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder of hematopoietic stem cells. Although there have been advancements in treatment, there is still a need to develop a biotherapeutic agent. A new variant of the human alpha-lactalbumin-oleic acid (HALOA) complex has been synthesized, which showed similarities with SNARE. The native α-LA was treated with EDTA to remove Ca2+ ions confirmed by ICP-OES and Arsenazo III to unfold and attain apo structure. The apo LA was mixed with OA in a specific ratio, leading to HALOA complex formation. The conformational state from native to complex was elucidated by circular dichroism (far; 190-260 nm and near; 260-340 nm UV-CD), which confirmed that the complex consists of a majority of turns and ß-sheet structure. SDS-PAGE result showed the masking effect of OA on apo α-LA. In the lane of the complex, there was no band detected. However, 1-anilino-8-naphthalene sulfonate (ANS) dye has shown maximum fluorescence intensity with the complex because of the availability of hydrophobic patches, which was further validated by NMR spectroscopy indicating the masking effect of OA on the apo α-LA. The SNARE behavior of the complex (500 nm) has been confirmed by TEM. This new structural variant complex shows anti-tumor activity on chronic myeloid leukemia by targeting the IL-8, survivin, and induces apoptosis through DNA fragmentation, but not against normal cells. Overall, the formulated complex shows that SNARE-like behavior can be used as a promising anti-tumor agent with lower toxicity and maximum bioavailability.


Asunto(s)
Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva , Antineoplásicos/farmacología , Dicroismo Circular , Humanos , Lactalbúmina , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Ácido Oléico
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