Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Immunol ; 15: 1369406, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835760

RESUMO

Epigenetic mechanisms are involved in several cellular functions, and their role in the immune system is of prime importance. Histone deacetylases (HDACs) are an important set of enzymes that regulate and catalyze the deacetylation process. HDACs have been proven beneficial targets for improving the efficacy of immunotherapies. HDAC11 is an enzyme involved in the negative regulation of T cell functions. Here, we investigated the potential of HDAC11 downregulation using RNA interference in CAR-T cells to improve immunotherapeutic outcomes against prostate cancer. We designed and tested four distinct short hairpin RNA (shRNA) sequences targeting HDAC11 to identify the most effective one for subsequent analyses. HDAC11-deficient CAR-T cells (shD-NKG2D-CAR-T) displayed better cytotoxicity than wild-type CAR-T cells against prostate cancer cell lines. This effect was attributed to enhanced activation, degranulation, and cytokine release ability of shD-NKG2D-CAR-T when co-cultured with prostate cancer cell lines. Our findings reveal that HDAC11 interference significantly enhances CAR-T cell proliferation, diminishes exhaustion markers PD-1 and TIM3, and promotes the formation of T central memory TCM populations. Further exploration into the underlying molecular mechanisms reveals increased expression of transcription factor Eomes, providing insight into the regulation of CAR-T cell differentiation. Finally, the shD-NKG2D-CAR-T cells provided efficient tumor control leading to improved survival of tumor-bearing mice in vivo as compared to their wild-type counterparts. The current study highlights the potential of HDAC11 downregulation in improving CAR-T cell therapy. The study will pave the way for further investigations focused on understanding and exploiting epigenetic mechanisms for immunotherapeutic outcomes.


Assuntos
Histona Desacetilases , Imunoterapia Adotiva , Neoplasias da Próstata , RNA Interferente Pequeno , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia , Neoplasias da Próstata/imunologia , Humanos , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Animais , Camundongos , RNA Interferente Pequeno/genética , Linhagem Celular Tumoral , Imunoterapia Adotiva/métodos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Inativação Gênica , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Cells ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38534399

RESUMO

CD19-specific CAR-T immunotherapy has been extensively studied for the treatment of B-cell lymphoma. Recently, cholesterol metabolism has emerged as a modulator of T lymphocyte function and can be exploited in immunotherapy to increase the efficacy of CAR-based systems. Acetyl-CoA acetyltransferase 1 (ACAT1) is the major cholesterol esterification enzyme. ACAT1 inhibitors previously shown to modulate cardiovascular diseases are now being implicated in immunotherapy. In the present study, we achieved knockdown of ACAT1 in T cells via RNA interference technology by inserting ACAT1-shRNA into anti-CD19-CAR-T cells. Knockdown of ACAT1 led to an increased cytotoxic capacity of the anti-CD19-CAR-T cells. In addition, more CD69, IFN-γ, and GzmB were expressed in the anti-CD19-CAR-T cells. Cell proliferation was also enhanced in both antigen-independent and antigen-dependent manners. Degranulation was also improved as evidenced by an increased level of CD107a. Moreover, the knockdown of ACAT1 led to better anti-tumor efficacy of anti-CD19 CAR-T cells in the B-cell lymphoma mice model. Our study demonstrates novel CAR-T cells containing ACAT1 shRNA with improved efficacy compared to conventional anti-CD19-CAR-T cells in vitro and in vivo.


Assuntos
Linfoma de Células B , Receptores de Antígenos de Linfócitos T , Linfócitos T , Animais , Camundongos , Acetiltransferases , Imunoterapia Adotiva , Linfoma de Células B/patologia , Anticorpos , Proliferação de Células , RNA Interferente Pequeno
3.
Biomed Pharmacother ; 168: 115740, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37865999

RESUMO

The efficacy of CAR-T cell therapy has been hindered by several factors that are intrinsic to the tumor microenvironment. Many strategies are being employed to overcome these barriers and improve immunotherapies efficacy. Interleukin (IL)- 4 is a cytokine released by tumor cells inside the tumor microenvironment and it can oppose T cell effector functions via engagement with the IL-4 receptor on the surface of T cells. To overcome IL-4-mediated immunosuppressive signals, we designed a novel inverted cytokine receptor (ICR). Our novel CAR construct (4/15NKG2D-CAR), consisted of an NKG2D-based chimeric antigen receptor, co-expressing IL-4R as an extracellular domain and IL-15R as a transmembrane and intracellular domain. In this way, IL-4R inhibitory signals were converted into IL-15R activation signals downstream. This strategy increased the efficacy of NKG2D-CAR-T cells in the pancreatic tumor microenvironment in vitro and in vivo. 4/15NKG2D-CAR-T cells exhibited increased activation, degranulation, cytokine release, and cytotoxic ability of NKG2D-CAR-T cells against IL-4+ pancreatic cell lines. Furthermore, 4/15NKG2D-CAR-T cells exhibited more expansion, less exhaustion, and an increased percentage of less differentiated T cell phenotypes in vitro when compared with NKG2D-CAR-T cells. That is why IL-4R/IL-15R-modified CAR-T cells eradicated more tumors in vivo and outperformed NKG2D-CAR-T cells. Thus, we report here a novel NKG2D-CAR-T cells that could overcome IL-4-mediated immunosuppression in solid tumors.


Assuntos
Citocinas , Receptores de Antígenos Quiméricos , Linhagem Celular Tumoral , Citocinas/metabolismo , Imunoterapia Adotiva , Interleucina-15/metabolismo , Interleucina-4/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores de Interleucina-15/metabolismo , Linfócitos T , Microambiente Tumoral , Humanos , Células HEK293
4.
Int J Mol Sci ; 24(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629018

RESUMO

The microenvironment of most tumors is complex, comprising numerous aspects of immunosuppression. Several studies have indicated that the adrenergic system is vital for controlling immunological responses. In the context of the tumor microenvironment, nor-adrenaline (NA) is poured in by innervating nerves and tumor tissues itself. The receptors for nor-adrenaline are present on the surfaces of cancer and immune cells and are often involved in the activation of pro-tumoral signaling pathways. Beta2-adrenergic receptors (ß2-ARs) are an emerging class of receptors that are capable of modulating the functioning of immune cells. ß2-AR is reported to activate regulatory immune cells and inhibit effector immune cells. Blocking ß2-AR increases activation, proliferation, and cytokine release of T lymphocytes. Moreover, ß2-AR deficiency during metabolic reprogramming of T cells increases mitochondrial membrane potential and biogenesis. In the view of the available research data, the immunosuppressive role of ß2-AR in T cells presents it as a targetable checkpoint in CAR-T cell therapies. In this review, we have abridged the contemporary knowledge about adrenergic-stress-mediated ß2-AR activation on T lymphocytes inside tumor milieu.


Assuntos
Receptores de Antígenos Quiméricos , Linfócitos T , Adrenérgicos , Norepinefrina , Terapia Baseada em Transplante de Células e Tecidos , Epinefrina
5.
Pharmaceuticals (Basel) ; 16(5)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37242471

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is among the leading causes of nosocomial infections and forms biofilms, which are difficult to eradicate because of their increasing resistance to antimicrobial agents. This is especially true for pre-existing biofilms. The current study focused on evaluating the efficacy of three ß-lactam drugs, meropenem, piperacillin, and tazobactam, alone and in combination against the MRSA biofilms. When used individually, none of the drugs exhibited significant antibacterial activity against MRSA in a planktonic state. At the same time, the combination of meropenem, piperacillin, and tazobactam showed a 41.7 and 41.3% reduction in planktonic bacterial cell growth, respectively. These drugs were further assessed for biofilm inhibition and removal. The combination of meropenem, piperacillin, and tazobactam caused 44.3% biofilm inhibition, while the rest of the combinations did not show any significant effects. Results also revealed that piperacillin and tazobactam exhibited the best synergy against the pre-formed biofilm of MRSA, with 46% removal. However, adding meropenem to the piperacillin and tazobactam combination showed a slightly reduced activity towards the pre-formed biofilm of MRSA and removed 38.7% of it. Although the mechanism of synergism is not fully understood, our findings suggest that these three ß-lactam drugs can be used in combination as very effective therapeutic agents for the treatment of pre-existing MRSA biofilms. The in vivo experiments on the antibiofilm activity of these drugs will pave the way for applying such synergistic combinations to clinics.

6.
Front Immunol ; 13: 1034444, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518757

RESUMO

Viruses are submicroscopic, obligate intracellular parasites that carry either DNA or RNA as their genome, protected by a capsid. Viruses are genetic entities that propagate by using the metabolic and biosynthetic machinery of their hosts and many of them cause sickness in the host. The ability of viruses to adapt to different hosts and settings mainly relies on their ability to create de novo variety in a short interval of time. The size and chemical composition of the viral genome have been recognized as important factors affecting the rate of mutations. Coronavirus disease 2019 (Covid-19) is a novel viral disease that has quickly become one of the world's leading causes of mortality, making it one of the most serious public health problems in recent decades. The discovery of new medications to cope with Covid-19 is a difficult and time-consuming procedure, as new mutations represent a serious threat to the efficacy of recently developed vaccines. The current article discusses viral mutations and their impact on the pathogenicity of newly developed variants with a special emphasis on Covid-19. The biology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), its mutations, pathogenesis, and treatment strategies are discussed in detail along with the statistical data.


Assuntos
COVID-19 , Vírus , Humanos , SARS-CoV-2/genética , Genoma Viral , Vírus/genética , Mutagênese
7.
Physiol Plant ; 174(5): e13758, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36281843

RESUMO

This study adopts a very effective high-performance liquid chromatography (HPLC) technique for the quantitative determination of rosmarinic acid (RA) and PCR-based amplification of biosynthetic key regulators in Isodon rugosus, Daphne mucronata, and Viburnum grandiflorum from the lower Himalayan regions. Rosmarinic acid is engaged in a variety of biological processes and has significant industrial significance. In this study, it was identified from crude methanolic extract using thin-layer chromatography with a standard, and its content was quantified using HPLC without interrupting spikes using a mixture of methanol and deionized water containing acetonitrile (70:30 v/v) and acetic acid (0.1% v/v) at UV 310 nm absorption. We used RT-PCR to identify cDNAs encoding PAL, C4H, and RAS, and Image J's semi-quantitative analysis to quantify the expression levels of genes involved in RA production from chosen plant material. The highest levels of PAL, C4H, and RAS were detected, by band intensity, in the leaves and flowers of I. rugosus, which also exhibited a substantial quantity of RA. However, in V. grandiflorum and D. mucronata the transcript of the given genes was low. The concentration of RA ranged from 187.7 to 21.2 mg g-1 for I. rugosus, 17.42 to 5.42 mg g-1 for V. grandiflorum, and 15.19 mg g-1 for D. mucronata. This study demonstrated that the method for quantifying RA from a crude methanolic extract was effective, indicating that I. rugosus might be used as an indigenous alternative source of RA.


Assuntos
Metanol , Fenilalanina , Cinamatos , Extratos Vegetais/química , Acetatos , Acetonitrilas , Água , Cromatografia Líquida de Alta Pressão , Ácido Rosmarínico
8.
Front Pharmacol ; 13: 996321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188601

RESUMO

Rheumatoid arthritis and osteoarthritis overlap many molecular mechanisms of cartilage destruction. Wear and tear in cartilage is chondrocyte-mediated, where chondrocytes act both as effector and target cells. In current study, role of ß2-AR was studied in chondrocytes both in vitro and in vivo. High grade inflammation in vitro and in vivo disease models led to decline in anti-inflammatory ß2-AR signaling and use of ß2-AR agonist attenuated arthritis symptoms. Detailed analysis in chondrocytes revealed that Isoprenaline (ISO) and Salbutamol (SBT) increased cell viability and relative Bcl-2 expression, meanwhile, decreased proteins levels of TNF-α, IL-6 and IL-8 in arthritic chondrocytes when compared with control, respectively. SBT preserved physiological concentration of antioxidant enzymes (CAT, POD, SOD and GSH) in cartilage homogenates and ISO inhibited IL-1ß-mediated genotoxicity in arthritic chondrocytes. Moreover, ß2-AR agonist increased mitochondrial biogenesis and proteoglycan biosynthesis by upregulating the gene expression of PGC1-α, NRF2 and COL2A1, Acan, respectively. ISO and SBT inhibited extracellular matrix (ECM) degradation by downregulating the gene expression of MMP1, MMP3, MMP9 and ADAMTS5 in vitro and in vivo study. In mechanism, ß2-AR agonists decreased ß-arrestin and GRK2 pathway, and as a result mice receiving SBT did not exhibit severe disease. Hence our data suggest ß2-AR agonist administered at disease onset can inhibit receptor internalization by downregulating the expression of ß-arrestin and GRK2 in chondrocytes.

9.
Front Pharmacol ; 13: 1077570, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36588726

RESUMO

Diabetes mellitus is a chronic metabolic complaint with numerous short- and long-term complications that harm a person's physical and psychological health. Plumeria obtusa L. is a traditional medicine used in the treatment of diabetes to reduce complications related to behavior. Plumeria is a genus with antipsychotic activities. The objective of this study was to examine the effects of a methanolic extract of Plumeria obtusa L. in the attenuation of diabetes, on symptoms of Alzheimer disease, and on other associated behavioral aspects. A single dose of alloxan was administered to an experimental group of rats to induce development of diabetes (150 mg/kg, intraperitoneal) and the rats were then administered selected doses of methanolic extract of Plumeria obtusa L. (Po.Cr) or glibenclamide (0.6 mg/kg) for 45 consecutive days. Behavioral effects were evaluated using three validated assays of anxiety-related behavior: the open field test, the light and dark test, and the elevated plus maze. Anti-depressant effects of Plumeria obtusa L. were evaluated using the forced swim test (FST) and memory and learning were assessed using the Morris water maze (MWM) task. Po.Cr was also evaluated for phytochemicals using total phenolic content (TPC), total flavonoid content (TFC), and high-performance liquid chromatography assays, and antioxidant capability was assessed through assays of DPPH radical scavenging, total oxidation capacity, and total reducing capacity. In the alloxan-induced model of diabetes, the administration of Po.Cr and glibenclamide for 45 days produced a marked decrease (p < 0.001) in hyperglycemia compared to control animals. Po.Cr treatment also resulted in improvement in indicators, such as body weight and lipid profile (p < 0.05), as well as restoration of normal levels of alanine transaminase (ALT) (p < 0.001), a biomarker of liver function. Diabetic rats presented more Alzheimer-like symptoms, with greater impairment of memory and learning, and increased anxiety and depression compared to non-diabetic normal rats, whereas treated diabetic rats showed significant improvements in memory and behavioral outcomes. These results demonstrate that Po.Cr reversed alloxan-induced hyperglycemia and ameliorated Alzheimer-related behavioral changes, which supports additional study and assessment of conventional use of the plant to treat diabetes and associated behavioral complications.

10.
Oncogenesis ; 10(9): 62, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548478

RESUMO

Pancreatic carcinoma (PC) is one of the most common malignancies. Chimeric antigen receptor (CAR)-modified T cells has achieved remarkable efficacy in the treatment of hematological malignancies. However, lack of tumor-specific targets and the existence of inhibitory factors limit the function of CAR T cells when treating solid tumors. 4.1R has been reported to suppress the anti-tumor activity of T cell responses. In this study, we investigated the anti-tumor activity of 4.1R deletion in natural killer group 2D (NKG2D)-CAR T cells against PC. The CAR T cells were obtained by transfecting T cells with lentiviral vector carrying NKG2D-CAR, NC-NKG2D-CAR, or KD2-NKG2D-CAR. In vitro, NKG2D-CAR T cells showed higher cytotoxicity than Mock T cells. However, compared to NKG2D-CAR T cells, furtherly higher cytotoxicity against PC cells in a dose-dependent manner was found in KD2-NKG2D-CAR T cells. In addition, the proliferation rate and cytotoxic activity of KD2-NKG2D-CAR T cells were significantly higher than those of NKG2D-CAR T cells. Besides, the inhibitory receptors PD-1 and TIM-3 were expressed in lower level on KD2-NKG2D-CAR T cells. In vivo, KD2-NKG2D-CAR T cells suppressed tumor growth more effectively in a xenograft model compared to NKG2D-CAR T cells. Mechanistically, 4.1R regulated CAR T cell function via activating ERK signaling pathway. Therefore, the study provides a new idea to enhance the anti-tumor efficiency of CAR T therapy.

11.
Microsc Res Tech ; 84(7): 1522-1530, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33608993

RESUMO

Advanced research, development, and application of silver nanoparticles is proceeding in recent times due to their incredible utilization in various fields. Present study was focused on the production, characterization, and antifungal activities of silver nanoparticles (AgNPs). An environment friendly extracellular biosynthetic approach was adopted to produce the AgNPs by using bacteria, fungi, and sugarcane husk. Agents used for reduction of silver to nanoparticles were taken from culture filtrate of plant growth promoting bacteria, Fusarium oxysporum and supernatant extract of sugarcane husk. Nanoparticles were also characterized by scanning electron microscopy (SEM). Synthesis of colloidal AgNPs was observed by UV-Visible diffused reflectance spectroscopy (UV-Vis DRS). Primary peak of surface plasmon resonance band was noticed around 339.782, 336.735, and 338.258 nm for bacterial, fungal, and sugarcane husk produced AgNPs. Structure of all biologically produced nanoparticles were crystalline cubic with nano size of 45.41, 49.06, and 42.75 nm for bacterial, fungal, and sugarcane husk-based nanoparticles, respectively as calculated by Debye-Scherrer equation using XRD. Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of various compounds that aid in the reduction, capping, and stability of AgNPs. The antifungal activity of AgNPs was also investigated for sugarcane fungal pathogens Colletotricum falcatum and Fusarium moniliforme. All nanoparticles exhibit prominent antifungal activities. Maximum zone of fungal inhibition was noticed about 18, 19, and 21 mm for C. falcatum while 21, 20, and 24 mm for F. moniliforme in case of bacterial, fungal, and plant-based nanoparticles (15 ppm), respectively. Best fungal inhibition was observed under application of sugarcane husk based AgNPs. Moreover, biologically produced AgNPs responded better towards the suppression of F. moniliforme in comparison to C. falcatum. Mentioned sources in present study can be ecofriendly nano-factories for biosynthesis of AgNPs and mankind should benefit from their commercial application.


Assuntos
Nanopartículas Metálicas , Saccharum , Antibacterianos , Fusarium , Extratos Vegetais , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Cancers (Basel) ; 12(9)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933182

RESUMO

B cell aplasia caused by "on-target off-tumor" toxicity is one of the clinical side effects during CD19-targeted chimeric antigen receptor (CAR) T (CD19-CAR-T) cells treatment for B cell malignancies. Persistent B cell aplasia was observed in all patients with sustained remission, which increased the patients' risk of infection. Some patients even died due to infection. To overcome this challenge, the concept of incorporating an inhibitory CAR (iCAR) into CAR-T cells was introduced to constrain the T cells response once an "on-target off-tumor" event occurred. In this study, we engineered a novel KIR/PD-1-based inhibitory CAR (iKP CAR) by fusing the extracellular domain of killer cell immunoglobulin-like receptors (KIR) 2DL2 (KIR2DL2) and the intracellular domain of PD-1. We also confirmed that iKP CAR could inhibit the CD19 CAR activation signal via the PD-1 domain and CD19-CAR-T cells bearing an iKP CAR (iKP-19-CAR-T) exerted robust cytotoxicity in vitro and antitumor activity in the xenograft model of CD19+HLA-C1- Burkitt's lymphoma parallel to CD19-CAR-T cells, whilst sparing CD19+HLA-C1+ healthy human B cells both in vitro and in the xenograft model. Meanwhile, iKP-19-CAR-T cells exhibited more naïve, less exhausted phenotypes and preserved a higher proportion of central memory T cells (TCM). Our data demonstrates that the KIR/PD-1-based inhibitory CAR can be a promising strategy for preventing B cell aplasia induced by CD19-CAR-T cell therapy.

13.
Cancers (Basel) ; 12(7)2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32698361

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is a promising approach in treating solid tumors but the therapeutic effect is limited. Prostate cancer is a typical solid malignancy with invasive property and a highly immunosuppressive microenvironment. Ligands for the NKG2D receptor are primarily expressed on many cancer cells, including prostate cancer. In this study, we utilized NKG2D-based CAR to treat prostate cancer, and improved the therapeutic effect by co-expression of IL-7. The results showed that NKG2D-CAR T cells performed significantly increased cytotoxicity against prostate cancer compared to non-transduced T cells in vitro and in vivo. Moreover, the introduction of the IL-7 gene into the NKG2D-CAR backbone enhanced the production of IL-7 in an antigen-dependent manner. NKG2DIL7-CAR T cells exhibited better antitumor efficacy at 16 h and 72 h in vitro, and inhibited tumor growth in xenograft models more effectively. In mechanism, enhanced proliferation and Bcl-2 expression in CD8+ T cells, decreased apoptosis and exhaustion, and increased less-differentiated cell phenotype may be the reasons for the improved persistence and survival of NKG2DIL7-CAR T cells. In conclusion, these findings demonstrated that NKG2D is a promising option for CAR T-cell therapy on prostate cancer, and IL-7 has enhanced effect on NKG2D-based CAR T-cell immunotherapy, providing a novel adoptive cell therapy for prostate cancer either alone or in combination with IL-7.

14.
Plant Physiol Biochem ; 151: 640-649, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32339911

RESUMO

Sustainability in crop production has emerged as one of the most important concerns of present era's agricultural systems. Plant growth promoting bacteria (PGPB) has been characterized as a set of microorganisms used for enhancing plant growth and a tool for biological control of phytopathogens. However, the inconsistent performance of these bacteria from laboratory/greenhouse to field level has emerged due to prevailing abiotic stresses in fields. Sugarcane crop encounters a combination of biotic and abiotic stresses during its long developmental stages. Nevertheless, the selection of antagonistic PGPB with abiotic stress tolerance would be beneficial for end-user by the successful establishment of product with required effects under field conditions. Stress tolerant Bacillus xiamenensis strain (PM14) isolated from the sugarcane rhizosphere grown in the fields was examined for various PGP activities, enzyme assays, and antibiotic resistance. Strain was screened for in vitro tolerance against drought, salinity, heat stress, and heavy metal toxicity. Inhibition co-efficient of B. xiamenensis PM14 was also calculated against six phyto-pathogenic fungi, including Colletotrichum falcatum (53.81), Fusarium oxysporum (68.24), Fusarium moniliforme (69.70), Rhizoctonia solani (71.62), Macrophomina phaseolina (67.50), and Pythium splendens (77.58). B. xiamenensis is reported here for the first time as the rhizospheric bacterium which possesses resistance against 12 antibiotics and positive results for all in vitro PGP traits except HCN production. Role of 1-aminocyclopropane-1-carboxylate deaminase in the amelioration of biotic and abiotic stress was also supported by the amplification of acds gene. Moreover, in vitro and in vivo experiments revealed B. xiamenensis as the potential antagonistic PGPR and bio-control agent. Results of greenhouse experiment against sugarcane red rot indicated that inoculation of B. xiamenensis to sugarcane plants could suppress the disease symptoms and enhance plant growth. Augmented production of antioxidative enzymes and proline content may lead to the induced systemic resistance against red rot disease of sugarcane. Thus, the future application of native multi-stress tolerant bacteria as bio-control agents in combination with current heat, drought, salinity, and heavy metal tolerance strategy could contribute towards the global food security.


Assuntos
Bacillus , Resistência à Doença , Saccharum , Bacillus/fisiologia , Resistência à Doença/fisiologia , Fungos/fisiologia , Doenças das Plantas/microbiologia , Saccharum/microbiologia
15.
Pak J Med Sci ; 35(6): 1647-1651, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31777509

RESUMO

OBJECTIVE: To compare improvement in Best Corrected Visual Acuity (BCVA) by Full Time Occlusion (FTO) or Part Time Occlusion (PTO) technique in children with monocular amblyopia. METHODS: This randomized control trial was conducted at Combined Military Hospital, Gujranwala from April 2018 to June 2019. A total of 52 children, diagnosed with non-pathological ametropic amblyopia were randomly divided in two groups. Both underwent cycloplegic refraction and assessment of BCVA. Group A underwent FTO for eight weeks with patch removal only during sleep. Group B underwent PTO for 8 weeks with patching done for six hours a day, out of which 1-2 hours were utilized in near work. Final BCVA was checked at eight weeks, and compared between two groups. RESULTS: Mean age of study population was 11.06±3.30 years. Mean BCVA before amblyopia treatment was 0.70±0.20 logMAR, and mean BCVA after eight weeks of amblyopia treatment in both groups was 0.29±0.18 logMAR. Difference in BCVA between both groups was statistically significant (p= 0.023). Mean improvement in lines on Snellen's Visual acuity chart was 1.92±1.35 lines. In our study, 92% of children in FTO group and 66.6% of children in PTO group achieved BCVA of 6/12 or better. CONCLUSIONS: Full time occlusion in children with monocular amblyopia results in greater improvement in BCVA as compared to part time occlusion of six hours per day.

16.
Pak J Med Sci ; 33(1): 3-7, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367162

RESUMO

OBJECTIVE: To determine the visual outcome in patients with acute Central serous chorioretinopathy (CSCR) and to analyze the association of clinical, angiographic and tomographic factors with final visual outcome in Pakistani population. METHODS: This study was conducted at AFIO Rawalpindi and PNS Shifa Naval hospital Karachi from November 2011 to August 2016. Fifty five eyes of 53 patients with acute CSCR were included. All patients underwent a detailed ophthalmic examination including SD OCT imaging at baseline, One month and three month and FFA was performed at baseline. Primary outcome measures were measurement of initial and final BCVA and CFT. SPSS 13.0 was used for the analysis of data. RESULTS: Mean age of study population was 36.66 ± 6.24 years. On OCT mean CFT at baseline was 467.49 ± 144.80 µm in affected eye, whereas mean CFT measurements at final follow up was 244.67 ± 32.99 µm (p <0.01). Presenting mean log MAR BCVA was 0.47 ± 0.25 and final mean log MAR BCVA was 0.18 ± 0.14 (p <0.01). Baseline BCVA showed statistically significant association with final BCVA (p=0.03). CONCLUSION: Presenting VA of 6/12 or better is associated with favorable visual outcome in patients with acute CSCR.

17.
BMC Complement Altern Med ; 15: 349, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26445953

RESUMO

BACKGROUND: Plants provide an alternative source to manage various human disorders due to diverse metabolites. Euphorbia dracunculoides of family Euphorbiaceae is used by local practitioners in rheumatism, epilepsy, edema, snake bite, warts and also possesses diuretic and purgative effects. The present study evaluated the antioxidant, anti-inflammatory and analgesic activities of various extracts of E. dracunculoides. Further, phytochemical constituents of the leading extracts were also investigated. METHODS: Dry powder of E. dracunculoides was extracted with n-hexane (EDH), acetone (EDA), ethanol (EDE), ethanol + water (1:1) (EDEW) and methanol (EDM) and screened for phytochemical classes, total phenolic (TPC) and flavonoid content (TFC). Antioxidant effects of the extracts were manifested by in vitro multidimensional assays. The anti-inflammatory and analgesic activities of the extracts were evaluated through carrageenan induced paw edema and hot plate test in rat. In addition, GC-MS analysis of EDH and HPLC-DAD analysis of EDEW was carried out to determine the presence of active constituents. RESULTS: Qualitative analysis of various extracts of E. dracunculoides assured the existence of tannins and coumarins while presence of anthraquinones and anthocyanins was not traced in these extracts. Maximum quantity of TPC and TFC was recorded in EDEW followed by EDE. EDEW and EDE showed significant antioxidant activities with therapeutic potential against hydroxyl and phosphomolybdate radicals, ß-carotene bleaching assay and in reducing of iron while moderate to low scavenging abilities were recorded for DPPH, nitric oxide and for iron chelation. During anti-inflammatory activity after 4 h of drug administration the 300 mg/kg body weight dose of EDH (68.660 ± 10.502%) and EDE (51.384 ± 8.623%) exhibited strong anti-inflammatory activity and reduced the carrageenan-induced paw edema in rat as compared to standard drug diclofenac sodium (78.823 ± 6.395%). Treatment of rats with EDH (70.206 ± 5.445%) and EDE (56.508 ± 6.363%) after 90 min showed significant increase in percent latency time in hot plate test as compared to morphine (63.632 ± 5.449%) treatment in rat. GC-MS analysis of EDH indicated the presence of 30 compounds predominantly of steroids and terpenoids. HPLC-DAD analysis against known standards established the presence of rutin, catechin, caffeic acid and myricetin in EDEW. CONCLUSION: Our results suggest that presence of various polyphenolics, terpenoids and steroids render E. dracunculoides with therapeutic potential for oxidative stress and inflammation related disorders.


Assuntos
Analgésicos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Edema/tratamento farmacológico , Euphorbia/química , Extratos Vegetais/administração & dosagem , Analgésicos/química , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Edema/imunologia , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...