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1.
Microvasc Res ; 155: 104712, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909952

RESUMO

BACKGROUND: Leprosy, a chronic infectious disease, is associated with various nail changes. Its etiopathogenesis is multifaceted, with microvascular damage being crucial. Nail fold capillaroscopy (NFC) emerges as a novel tool for detecting early vascular deficits in leprosy. The study aimed to assess and provide a complete clinical characterization of NFC changes in leprosy patients. METHODS: It is an observational cross-sectional study, done over a period of 1.5 year (January 2021 to august 2022) in a tertiary care hospital, encompassing 60 patients diagnosed with leprosy (18-60 years). After obtaining informed consent; detailed history, complete cutaneous and neurological examinations were conducted. All fingernails and toenails were examined for clinical changes. Subsequently, onychoscopy was performed using USB type of video-dermatoscope (Model AM7115MZT Dino-lite), a non-invasive tool. This was followed by NFC which was done for all fingernails and images were recorded by single operator, which were then assessed for quantitative and qualitive changes and statistical analysis was conducted using SPSS v20, with mean capillary density compared using Student's t-test, morphological change frequencies assessed by proportions, and group comparisons made using Chi-square or Fischer exact tests, with a significance threshold of p < 0.05. RESULTS: Among the 60 patients, 39 were in the lepromatous group, which included both borderline lepromatous (BL) and lepromatous leprosy (LL) patients, and 17 were in the tuberculoid group, which included borderline tuberculoid (BT) leprosy patients; 23.3 % had Type 1 reactions, and 18.3 % had Type 2 reactions. Nail fold capillaroscopy (NFC) showed microvasculature changes in 93.3 % of patients. The average capillary density was 6.8 ± 1.5 capillaries per mm, with the lepromatous group having a lower density (6.5 ± 1.09) compared to the tuberculoid group (7.0 ± 0.86). The most common NFC changes in the tuberculoid group were tortuous capillaries (70 %), capillary dropouts, and dilated capillaries (both 64.7 %). In the lepromatous group, capillary dropouts (82 %) were most frequent, followed by tortuous (69 %), receding (69 %), and dilated capillaries (66 %). A dilated and prominent subpapillary plexus was more common in the lepromatous group (35 %, p = 0.04). Patients with trophic changes in the lepromatous group had more capillary dropouts and bizarre capillaries. Capillary dropouts, dilated capillaries, and visible subpapillary venous plexus were more prevalent in patients with Type 2 reactions. CONCLUSION: NFC changes are prevalent in both tuberculoid and lepromatous leprosy, which may be an indicator of peripheral vascular compromise and trophic changes, especially in lepromatous leprosy. NFC can be an auxiliary tool for detecting microvascular abnormalities in leprosy patients.

2.
Nanoscale ; 16(21): 10350-10365, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38739006

RESUMO

Tumour cells secrete various proangiogenic factors like VEGF, PDGF, and EGF that result in the formation of highly vascularized tumours with an immunosuppressive tumour microenvironment. As tumour growth and metastasis are highly dependent on angiogenesis, targeting tumour vasculature along with rapidly dividing tumour cells is a potential approach for cancer treatment. Here, we specifically engineered sub-100 sized nanomicelles (DTX-CA4 NMs) targeting proliferation and angiogenesis using an esterase-sensitive phosphocholine-tethered docetaxel conjugate of lithocholic acid (LCA) (PC-LCA-DTX) and a poly(ethylene glycol) (PEG) derivative of an LCA-combretastatin A4 conjugate (PEG-LCA-CA4). DTX-CA4 NMs effectively inhibit the tumour growth in syngeneic (CT26) and xenograft (HCT116) colorectal cancer models, inhibit tumour recurrence, and enhance the percentage survival in comparison with individual drug-loaded NMs. DTX-CA4 NMs enhance the T cell-mediated anti-tumour immune response and DTX-CA4 NMs in combination with an immune checkpoint inhibitor, anti-PDL1 antibody, enhance the anti-tumour response. We additionally showed that DTX-CA4 NMs effectively attenuate the production of ceramide-1-phosphate, a key metabolite of the sphingolipid pathway, by downregulating the expression of ceramide kinase at both transcriptional and translational levels. Therefore, this study presents the engineering of effective DTX-CA4 NMs for targeting the tumour microenvironment that can be explored further for clinical applications.


Assuntos
Proliferação de Células , Ceramidas , Docetaxel , Micelas , Neovascularização Patológica , Animais , Ceramidas/química , Ceramidas/farmacologia , Humanos , Camundongos , Proliferação de Células/efeitos dos fármacos , Docetaxel/farmacologia , Docetaxel/química , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Ácido Litocólico/química , Ácido Litocólico/farmacologia , Polietilenoglicóis/química , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Estilbenos/química , Estilbenos/farmacologia , Células HCT116 , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Microambiente Tumoral/efeitos dos fármacos , Nanopartículas/química , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Angiogênese
3.
RNA Biol ; 21(1): 1-12, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303117

RESUMO

MicroRNAs regulate gene expression affecting a variety of plant developmental processes. The evolutionary position of Marchantia polymorpha makes it a significant model to understand miRNA-mediated gene regulatory pathways in plants. Previous studies focused on conserved miRNA-target mRNA modules showed their critical role in Marchantia development. Here, we demonstrate that the differential expression of conserved miRNAs among land plants and their targets in selected organs of Marchantia additionally underlines their role in regulating fundamental developmental processes. The main aim of this study was to characterize selected liverwort-specific miRNAs, as there is a limited knowledge on their biogenesis, accumulation, targets, and function in Marchantia. We demonstrate their differential accumulation in vegetative and generative organs. We reveal that all liverwort-specific miRNAs examined are encoded by independent transcriptional units. MpmiR11737a, MpmiR11887 and MpmiR11796, annotated as being encoded within protein-encoding genes, have their own independent transcription start sites. The analysis of selected liverwort-specific miRNAs and their pri-miRNAs often reveal correlation in their levels, suggesting transcriptional regulation. However, MpmiR11796 shows a reverse correlation to its pri-miRNA level, suggesting post-transcriptional regulation. Moreover, we identify novel targets for selected liverwort-specific miRNAs and demonstrate an inverse correlation between their expression and miRNA accumulation. In the case of one miRNA precursor, we provide evidence that it encodes two functional miRNAs with two independent targets. Overall, our research sheds light on liverwort-specific miRNA gene structure, provides new data on their biogenesis and expression regulation. Furthermore, identifying their targets, we hypothesize the potential role of these miRNAs in early land plant development and functioning.


Assuntos
Marchantia , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Marchantia/genética , Marchantia/metabolismo , Plantas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Genitália/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Plant Sci ; 338: 111903, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37865210

RESUMO

The global population is growing rapidly, and with it, the demand for food. In the coming decades, more and more people will be living in urban areas, where land for traditional agriculture is scarce. Urban agriculture can help to meet this growing demand for food in a sustainable way. Urban agriculture is the practice of growing food in urban areas. It can be done on rooftops, balconies, vacant lots, and even in alleyways. Urban agriculture can produce a variety of crops, including fruits, vegetables, and herbs. It can also help to improve air quality, reduce stormwater runoff, and create jobs. Biotechnology can be used to improve the efficiency and sustainability of urban agriculture. Biotechnological tools can be used to develop crops that are resistant to pests and diseases, that are more tolerant of drought and heat, and that have higher yields. Biotechnology can also be used to improve the nutritional value of crops. This review article discusses the need for and importance of urban agriculture, biotechnology, and genome editing in meeting the growing demand for food in urban areas. It also discusses the potential of biotechnology to improve the sustainability of urban agriculture.


Assuntos
Biotecnologia , Verduras , Humanos , Produtos Agrícolas/genética , Valor Nutritivo , Agricultura
5.
Plant Mol Biol ; 113(4-5): 121-142, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37991688

RESUMO

A wide variety of functional regulatory non-coding RNAs (ncRNAs) have been identified as essential regulators of plant growth and development. Depending on their category, ncRNAs are not only involved in modulating target gene expression at the transcriptional and post-transcriptional levels but also are involved in processes like RNA splicing and RNA-directed DNA methylation. To fulfill their molecular roles properly, ncRNAs must be precisely processed by multiprotein complexes. In the case of small RNAs, DICER-LIKE (DCL) proteins play critical roles in the production of mature molecules. Land plant genomes contain at least four distinct classes of DCL family proteins (DCL1-DCL4), of which DCL1, DCL3 and DCL4 are also present in the genomes of bryophytes, indicating the early divergence of these genes. The liverwort Marchantia polymorpha has become an attractive model species for investigating the evolutionary history of regulatory ncRNAs and proteins that are responsible for ncRNA biogenesis. Recent studies on Marchantia have started to uncover the similarities and differences in ncRNA production and function between the basal lineage of bryophytes and other land plants. In this review, we summarize findings on the essential role of regulatory ncRNAs in Marchantia development. We provide a comprehensive overview of conserved ncRNA-target modules among M. polymorpha, the moss Physcomitrium patens and the dicot Arabidopsis thaliana, as well as Marchantia-specific modules. Based on functional studies and data from the literature, we propose new connections between regulatory pathways involved in Marchantia's vegetative and reproductive development and emphasize the need for further functional studies to understand the molecular mechanisms that control ncRNA-directed developmental processes.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Embriófitas , Marchantia , MicroRNAs , Marchantia/genética , Marchantia/metabolismo , Plantas/genética , MicroRNAs/genética , Evolução Biológica , Arabidopsis/genética , Embriófitas/genética , Proteínas de Arabidopsis/genética , Ribonuclease III/genética , Ribonuclease III/metabolismo
6.
J Med Chem ; 65(22): 15312-15326, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36331380

RESUMO

Emergence of vancomycin resistance in Gram-positive bacteria and the prevalence of vancomycin-resistant Enterococci (VRE) infections are highly alarming as very limited antibiotic options are available against VRE infections. Here, we present the synthesis of cholic acid-derived dimeric amphiphiles where two cholic acid moieties are tethered through carboxyl terminals using different alkylene spacers. Our investigations revealed that dimer 5 possessing a propylene spacer and glycine-valine peptides tethered on hydroxyl groups is the most effective antimicrobial against VRE. Dimer 5 can permeabilize bacterial membranes, generate reactive oxygen species, and clear preformed biofilms. We further demonstrate that dimer 5 downregulates vancomycin-mediated transcriptional activation of the vanHAX gene cluster and does not allow VSE to develop vancomycin resistance until 100 generations. Therefore, this study, for the first time, presents a bacterial membrane-targeting amphiphile that can mitigate VRE infections and inhibit the emergence of vancomycin resistance.


Assuntos
Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ácido Cólico/farmacologia , Infecções por Bactérias Gram-Positivas/microbiologia , Testes de Sensibilidade Microbiana , Óperon , Vancomicina/farmacologia , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/genética , Farmacorresistência Bacteriana/genética
7.
Biomater Sci ; 10(18): 5158-5171, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35833261

RESUMO

Infections caused by multidrug-resistant Pseudomonas aeruginosa (P. aeruginosa) pose major challenges for treatment due to the acquired, adaptive, and intrinsic resistance developed by the bacteria. Accumulation of mutations, the ability to form biofilms, and the presence of lipopolysaccharides in the outer bacterial membranes are the key mechanisms of drug resistance. Here, we show that a polyaspartate-derived synthetic antimicrobial polymer (SAMP) with a hexyl chain (TAC6) is an effective adjuvant for a hydrophobic antibiotic, rifampicin. Our in vitro studies demonstrated that the combination of TAC6 and rifampicin is effective against clinically isolated multidrug-resistant strains of P. aeruginosa. Membrane permeabilization studies showed that TAC6 allows the permeabilization of bacterial membranes, and the accumulation of rifampicin inside the cells, thereby enhancing its activity. The combination of TAC6 and rifampicin can also degrade the P. aeruginosa biofilms, and therefore can mitigate the adaptive resistance developed by bacteria. We further demonstrated that the combination of TAC6 and rifampicin can clear P. aeruginosa-mediated wound infections effectively. Therefore, our study showed polyaspartate-derived SAMP to be an effective antibiotic adjuvant against P. aeruginosa infections.


Assuntos
Anti-Infecciosos , Infecções por Pseudomonas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Biofilmes , Farmacorresistência Bacteriana Múltipla , Humanos , Testes de Sensibilidade Microbiana , Peptídeos , Polímeros/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa , Rifampina/farmacologia , Rifampina/uso terapêutico
8.
Environ Pollut ; 300: 118887, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35077838

RESUMO

Aggrandized technological and industrial progression in past decades have occasioned immense depreciation in the quality of environment and ecosystem, majorly due to augmentation in the number of obnoxious pollutants incessantly being released in soil, water or air. Arsenic (As) is one such hazardous metalloid contaminating the environment which has the potential to detrimentally affect the life on earth. Even in minute quantity, As is known to cause various critical diseases in humans and toxicity in plants. Recent studies on nanoparticles (NPs) approve of their ability to qualify the criterion of becoming a potent tool for mitigating As-induced phytotoxicity. Nanoparticles are reported to promote plant growth under As-stress by stimulating various alterations at physiological, biochemical, and molecular levels. In this review, we provide an up-to-date compilation of research that has been carried out in comprehending the mechanisms utilized by nanoparticles including controlled As uptake and distribution in plants, maintenance of ROS homeostasis during stress and chelation and vacuolar sequestration of As so as to reduce the severity of toxicity induced by As, and potential areas of research in this field will also be indicated for future perspectives.


Assuntos
Intoxicação por Arsênico , Arsênio , Nanopartículas , Poluentes do Solo , Arsênio/análise , Ecossistema , Humanos , Nanopartículas/toxicidade , Substâncias Protetoras , Poluentes do Solo/análise
9.
Mol Aspects Med ; 81: 100999, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34325929

RESUMO

Gram-positive bacteria like Enterococcus faecium and Staphylococcus aureus, and Gram-negative bacteria like Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter Spp. are responsible for most of fatal bacterial infections. Bacteria present a handful of targets like ribosome, RNA polymerase, cell wall biosynthesis, and dihydrofolate reductase. Antibiotics targeting the protein synthesis like aminoglycosides and tetracyclines, inhibitors of RNA/DNA synthesis like fluoroquinolones, inhibitors of cell wall biosynthesis like glycopeptides and ß-lactams, and membrane-targeting polymyxins and lipopeptides have shown very good success in combating the bacterial infections. Ability of the bacteria to develop drug resistance is a serious public health challenge as bacteria can develop antimicrobial resistance against newly introduced antibiotics that enhances the challenge for antibiotic drug discovery. Therefore, bacterial membranes present a suitable therapeutic target for development of antimicrobials as bacteria can find it difficult to develop resistance against membrane-targeting antimicrobials. In this review, we present the recent advances in engineering of membrane-targeting antimicrobial amphiphiles that can be effective alternatives to existing antibiotics in combating bacterial infections.


Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Infecções Bacterianas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Infecções Bacterianas/tratamento farmacológico , Humanos
10.
Clin Vaccine Immunol ; 23(4): 282-93, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26843486

RESUMO

We previously reported that Rv1860 protein from Mycobacterium tuberculosis stimulated CD4(+)and CD8(+)T cells secreting gamma interferon (IFN-γ) in healthy purified protein derivative (PPD)-positive individuals and protected guinea pigs immunized with a DNA vaccine and a recombinant poxvirus expressing Rv1860 from a challenge with virulent M. tuberculosis We now show Rv1860-specific polyfunctional T (PFT) cell responses in the blood of healthy latently M. tuberculosis-infected individuals dominated by CD8(+) T cells, using a panel of 32 overlapping peptides spanning the length of Rv1860. Multiple subsets of CD8(+) PFT cells were significantly more numerous in healthy latently infected volunteers (HV) than in tuberculosis (TB) patients (PAT). The responses of peripheral blood mononuclear cells (PBMC) from PAT to the peptides of Rv1860 were dominated by tumor necrosis factor alpha (TNF-α) and interleukin-10 (IL-10) secretions, the former coming predominantly from non-T cell sources. Notably, the pattern of the T cell response to Rv1860 was distinctly different from those of the widely studied M. tuberculosis antigens ESAT-6, CFP-10, Ag85A, and Ag85B, which elicited CD4(+) T cell-dominated responses as previously reported in other cohorts. We further identified a peptide spanning amino acids 21 to 39 of the Rv1860 protein with the potential to distinguish latent TB infection from disease due to its ability to stimulate differential cytokine signatures in HV and PAT. We suggest that a TB vaccine carrying these and other CD8(+) T-cell-stimulating antigens has the potential to prevent progression of latent M. tuberculosis infection to TB disease.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Adulto , Proteínas de Bactérias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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