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1.
Mol Cell Biochem ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38413478

RESUMO

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

2.
Am J Bot ; : e16334, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825815

RESUMO

PREMISE: Cytogenetic traits such as an organism's chromosome number and genome size are taxonomically critical as they are instrumental in defining angiosperm diversity. Variations in these traits can be traced to evolutionary processes such as polyploidization, although geographic variations across cytogenetic traits remain underexplored. In the pantropical monocot family Zingiberaceae (~1500 species), cytogenetic traits have been well documented; however, the role of these traits in shaping taxonomic diversity and biogeographic patterns of gingers is not known. METHODS: A time-calibrated Bayesian phylogenetic tree was constructed for 290 taxa covering three of the four subfamilies in Zingiberaceae. We tested models of chromosome number and genome size evolution within the family and whether lineage age, taxonomic diversity, and distributional range explain the variations in the cytogenetic traits. Tests were carried out at two taxonomic ranks: within Zingiberaceae and within genus Hedychium using correlations, generalized linear models and phylogenetic least square models. RESULTS: The most frequent changes in chromosome number within Zingiberaceae were noted to be demi-polyploidization and polyploidization (~57% of the time), followed by ascending dysploidy (~27%). The subfamily Zingiberoideae showed descending dysploidy at its base, while Alpinioideae showed polyploidization at its internal nodes. Although chromosome counts and genome sizes did not corroborate with each other, suggesting that they are not equivalent; higher chromosome number variations and higher genome size variations were associated with higher taxonomic diversity and wider biogeographic distribution. CONCLUSIONS: Within Zingiberaceae, multiple incidences of polyploidization were discovered, and cytogenetic events appear to have reduced the genome sizes and increased taxonomic diversity, distributional ranges and invasiveness.

3.
Mol Biol Rep ; 51(1): 743, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874682

RESUMO

Human papillomavirus (HPV), a common cause of sexually transmitted diseases, may cause warts and lead to various types of cancers, which makes it important to understand the risk factors associated with it. HPV is the leading risk factor and plays a crucial role in the progression of cervical cancer. Viral oncoproteins E6 and E7 play a pivotal role in this process. Beyond cervical cancer, HPV-associated cancers of the mouth and throat are also increasing. HPV can also contribute to other malignancies like penile, vulvar, and vaginal cancers. Emerging evidence links HPV to these cancers. Research on the oncogenic effect of HPV is still ongoing and explorations of screening techniques, vaccination, immunotherapy and targeted therapeutics are all in progress. The present review offers valuable insight into the current understanding of the role of HPV in cancer and its potential implications for treatment and prevention in the future.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/complicações , Feminino , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/etiologia , Papillomaviridae/patogenicidade , Neoplasias/virologia , Neoplasias/terapia , Proteínas Oncogênicas Virais/metabolismo , Proteínas Oncogênicas Virais/genética , Fatores de Risco , Masculino
4.
Apoptosis ; 28(5-6): 683-701, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36652131

RESUMO

Cervical cancer is the fourth most common cancer affecting women worldwide after breast, colorectal and lung cancers. Owing to a lack of awareness and resources, low- and middle-income countries bear most of the burden of cervical cancer. In developed countries, the incidence rate has been halved over the past three decades due to robust screening and implementation of vaccine programs. HPV is not the sole cause of cervical cancer but acts as a principal factor in the pathogenesis of cervical cancer. By integrating into the host genome, its oncogenic proteins (E6 and E7) alter and interfere with the standard signal transduction machinery of the host. Apoptosis is a key pathway affected by aberrant genetic mutations, polymorphisms and epigenetic mechanisms during cervical carcinogenesis. Along with DNA methylation and histone modifications, non-coding RNAs have also been implicated as epigenetic modulators in various malignancies and are being explored for reversing disease severity. This review emphasizes various genetic and epigenetic approaches regulating apoptotic pathways and HPV E6 and E7 genes that can be targeted to overcome the challenges in cervical cancer treatment. In addition, it also discusses the apoptosis targeting novel drug molecules in cervical cancer which are currently undergoing clinical and pre-clinical trials.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Papillomavirus Humano , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/diagnóstico , Epigênese Genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Apoptose/genética , Proteínas Oncogênicas Virais/genética
5.
Apoptosis ; 28(7-8): 925-942, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37095313

RESUMO

Cervical cancer is among the leading causes of cancer-associated mortality in women. In spite of vaccine availability, improved screening procedures, and chemoradiation therapy, cervical cancer remains the most commonly diagnosed cancer in 23 countries and the leading cause of cancer deaths in 36 countries. There is, therefore, a need to come up with novel diagnostic and therapeutic targets. Long non-coding RNAs (lncRNAs) play a remarkable role in genome regulation and contribute significantly to several developmental and disease pathways. The deregulation of lncRNAs is often observed in cancer patients, where they are shown to affect multiple cellular processes, including cell cycle, apoptosis, angiogenesis, and invasion. Many lncRNAs are found to be involved in the pathogenesis as well as progression of cervical cancer and have shown potency to track metastatic events. This review provides an overview of lncRNA mediated regulation of cervical carcinogenesis and highlights their potential as diagnostic and prognostic biomarkers as well as therapeutic targets for cervical cancer. In addition, it also discusses the challenges associated with the clinical implication of lncRNAs in cervical cancer.


Assuntos
RNA Longo não Codificante , Neoplasias do Colo do Útero , Humanos , Feminino , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Apoptose/genética , Carcinogênese/genética
6.
J Cardiovasc Electrophysiol ; 34(4): 860-868, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36738148

RESUMO

INTRODUCTION: Catheter ablation for atrial fibrillation (AF) is a common therapeutic strategy for patients with either paroxysmal AF (PAF) or persistent AF (persAF), but long-term ablation success rates are imperfect. Maintenance of sinus rhythm immediately before ablation with antiarrhythmic drug (AAD) therapy has been associated with improved outcomes in patients undergoing ablation. Amiodarone has superior efficacy relative to other AADs. Whether failure of amiodarone to maintain sinus rhythm before ablation for either PAF or persAF is associated with poor outcomes is unknown. METHODS: A total of 307 patients who received amiodarone in a 1-year window before undergoing catheter ablation for AF were included. Patients were divided into amiodarone success (n = 183) and amiodarone failure (n = 124) groups based on the response to pre-ablation amiodarone treatment. Analysis of procedural outcomes as a function of response to amiodarone therapy was performed. Patients were followed for at least 12 months postablation, to assess outcomes (adverse events and arrhythmia recurrence). Procedural success was defined by the absence of documented arrhythmia (>30 s) without any antiarrhythmic agents beyond a 90-day blanking period. RESULTS: Following ablation for either PAF or persAF, freedom from any recurrent atrial arrhythmia at 1 year was 57.7% for the entire cohort. One-year freedom from recurrent arrhythmia in the amiodarone success group was comparable to that in the amiodarone failure group (55.7% vs. 60.5%; p = .54). Success rates following ablation did not vary by the response to amiodarone when analyzed for PAF or persAF subgroups. CONCLUSION: Failure to restore and maintain sinus rhythm with amiodarone before ablation for either PAF or persAF is not a predictor of ablation procedural failure. Amiodarone failure alone should not deter practitioners from considering ablation therapy for patients with AF.


Assuntos
Técnicas de Ablação , Amiodarona , Fibrilação Atrial , Ablação por Cateter , Humanos , Amiodarona/uso terapêutico , Fibrilação Atrial/cirurgia , Antiarrítmicos/uso terapêutico , Ablação por Cateter/efeitos adversos
7.
J Cardiovasc Electrophysiol ; 34(8): 1640-1647, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37365926

RESUMO

BACKGROUND: Studies have identified significant sex-based differences and disparities in the clinical presentation and treatment of atrial fibrillation (AF). Studies have shown women are less likely to be referred for catheter ablation, are older at the time of ablation, and are more likely to have recurrence after ablation. However, in most studies investigating AF ablation outcomes, the female cohorts were relatively small. The impact of sex on the outcome and safety of ablation procedures is still unclear. OBJECTIVE: To investigate sex-based differences in outcomes and complications after AF catheter ablation, with a significant female cohort METHOD: In this retrospective study, patients undergoing AF ablation from January 1, 2014, to March 31, 2021, were included. We investigated clinical characteristics, duration and progression of AF, number of EP appointments from diagnosis to ablation, procedural data, and procedure complications. RESULTS: Total of 1346 patients underwent first catheter ablation for AF during this period, including 896 (66.5%) male and 450 (33.4%) female patients. Female patients were older at the time of ablation (66.2 vs. 62.4 years; p < .001). Women had higher CHA2 DS2 -VASc (congestive heart failure, hypertension, age, diabetes, stroke, vascular disease, sex category) scores (3 vs. 2; p < .001) than men, expectedly, as the female sex warrants an additional point. 25.3% female patients had PersAF at the time of diagnosis versus 35.3% male patients (p < .001). At the time of ablation, 31.8% female patients had PersAF as compared to 43.1% male patients (p < .001), indicating progression of PAF to PersAF in both sexes. Women tried more AADs than men before ablation (1.13 vs. 0.98; p = .002). Male and female patients had no statistically significant difference in (a) arrhythmia recurrence at 1-year post ablation (27.7% vs. 30%; p = .38) or (b) procedural complication rate (1.8% vs. 3.1%; p = .56). CONCLUSION: Female patients were older and had higher CHA2 DS2 -VASc scores compared to males at the time of AF ablation. Women tried more AADs than men before ablation. One-year arrhythmia recurrence rates and procedural complications were similar in both sexes. No sex-based differences were observed in safety and efficacy of ablation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Humanos , Masculino , Feminino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fatores de Tempo , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva
8.
Langmuir ; 39(13): 4809-4818, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36944025

RESUMO

Surface modification of metallic nanoparticles (NPs) by stimuli-responsive polymers is a benign method to prepare smart colloidal composites which tune the characteristic properties of individual systems. The temperature-dependent transition of diblock copolymer poly(N-isopropylacrylamide)-block-poly(N-vinylcaprolactam) (PNIPMA-b-PVCL) synthesized using reversible addition-fragmentation chain transfer polymerization was studied by incorporating anisotropic gold NPs (AGPs) such as spheres (AuNSs), rods (AuNRs), cubes (AuNCs), and rhombic dodecahedrals (AuRDs). Shape-dependent physiochemical properties of nanostructures alter the lower critical solution temperature (LCST) of the chemical inhomogeneous diblock copolymer. Heterogeneous nucleation of AuNPs was facilitated by seed-mediated synthesis for incorporating uniformity. In the mixed system, the presence of PNIPAM-b-PVCL modifies the surface of AGPs through physisorption which is supported by transmission electron microscopy and field emission scanning electron microscopy showing the NPs embedding in the polymeric matrix. Furthermore, steady state fluorescence spectroscopy and Fourier transform infrared spectroscopy were performed to examine the phase transition behavior of PNIPAM-b-PVCL in AGPs. The formation of a smart polymer nanocomposite alters the physiochemical properties of the diblock copolymer as demonstrated from the variation of LCST in the dynamic light scattering measurement. Henceforth, functionalizing the surfaces of AGPs with a thermoresponsive diblock copolymer provides combinatorial benefits in the properties of smart polymeric colloidal systems with potential applications in bioimaging and drug delivery.

9.
Cell Biol Toxicol ; 39(6): 2437-2465, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37338772

RESUMO

Ranking from seventh in incidence to sixth in mortality, esophageal carcinoma is considered a severe malignancy of food pipe. Later-stage diagnosis, drug resistance, and a high mortality rate contribute to its lethality. Esophageal squamous cell carcinoma and esophageal adenocarcinoma are the two main histological subtypes of esophageal carcinoma, with squamous cell carcinoma alone accounting for more than eighty percent of its cases. While genetic anomalies are well known in esophageal cancer, accountability of epigenetic deregulations is also being explored for the recent two decades. DNA methylation, histone modifications, and functional non-coding RNAs are the crucial epigenetic players involved in the modulation of different malignancies, including esophageal carcinoma. Targeting these epigenetic aberrations will provide new insights into the development of biomarker tools for risk stratification, early diagnosis, and effective therapeutic intervention. This review discusses different epigenetic alterations, emphasizing the most significant developments in esophageal cancer epigenetics and their potential implication for the detection, prognosis, and treatment of esophageal carcinoma. Further, the preclinical and clinical status of various epigenetic drugs has also been reviewed.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Epigênese Genética/genética , Metilação de DNA/genética
10.
Chem Biodivers ; 20(10): e202301094, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37690999

RESUMO

A novel flavone glycoside was isolated from the methanolic extract of Cynotis axillaris Schult. Various analysis and characterization techniques were used to determine its structure and properties. The compound exhibited a melting point range of 231-232 °C and had a molecular formula of C27 H30 O14 . Several spectral characterization techniques were employed to establish the isolated compound's structure. These included UV-visible spectroscopy, FT-IR, LC-ESI-MS, and NMR spectroscopy. Based on these analyses, the structure of the isolated compound was determined to be 5,7,4'-trihydroxyflavone-8-α-L-rhamnopyranoside-4'-O-ß-D-galactopyranosyl. This structure indicates that it is a flavone glycoside consisting of a flavone (5,7,4'-trihydroxyflavone) moiety attached to a sugar molecule (galactopyranosyl) at position 4', which further bears a rhamnose group at position 8 of the flavone. In addition, to the structural characterization, the compound also demonstrated significant antibacterial efficacy against various bacterial pathogens, including Gram-positive bacteria such as Bacillus subtilis MTCC441 and Gram-negative bacteria such as Escherichia coli MTCC1098, Proteus vulgarize MTCC426, and Salmonella Typhimurium MTCC3224. The antimicrobial activity was evaluated by measuring the zone of inhibition in millimetres, which provides an indication of the compound's ability to inhibit bacterial growth. The study successfully identified and characterized a novel flavone glycoside from Cynotis axillaris Schult. and its antimicrobial activity.

11.
Phys Chem Chem Phys ; 23(35): 19740-19751, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525143

RESUMO

Carbon nanotubes (CNTs) are one of the unique and promising nanomaterials that possess plenty of applications, such as biosensors, advanced drug delivery systems and biotechnology. CNTs bind rapidly with proteins, which result in the formation of a protein coating layer known as a "protein corona" around the surface of the nanomaterial. This hinders their applications as a drug carrier and influences the properties of biological macromolecules. The present work focuses on studying the thermal stability and molecular level interactions of two heme proteins, hemoglobin (Hb) and myoglobin (Mb), in the presence of carboxylated functionalized multi-walled CNTs (CA-MWCNTs). Through the current study, the following steps have been taken to distinguish the biocompatibility of the hydrophilic surface CA-MWCNTs for heme proteins via a series of spectroscopic techniques and differential scanning calorimetry (DSC). UV-Visible and steady-state fluorescence spectroscopy were used to reveal changes in the aromatic amino acid residues of heme proteins upon the addition of CA-MWCNTs. Circular dichroism spectroscopy (CD) shows the alteration in the native structure of proteins in the presence of the nanomaterial. A tremendous increase in the size of the protein CA-MWCNTs system is observed in dynamic light scattering (DLS), which clearly manifests the protein corona formation. Unexpectedly, both proteins interact differently with CA-MWCNTs, which is observed in CD spectroscopy and DSC. In the presence of CA-MWCNTs, an increase in the transition temperature (Tm) was observed for Hb, while the Tm value decreases for Mb. Different interactions with proteins at the molecular scale may be the reason for this unexpected behavior. Henceforth, the present results can help in the design of the next-generation drug carrier nanomaterials with the idea of the heme protein corona formation prior to development.


Assuntos
Hemoglobinas/química , Mioglobina/química , Nanotubos de Carbono/química , Varredura Diferencial de Calorimetria , Ácidos Carboxílicos/química , Dicroísmo Circular , Hemoglobinas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Mioglobina/metabolismo , Coroa de Proteína , Espectrometria de Fluorescência , Temperatura de Transição
12.
J Cancer Educ ; 36(4): 844-849, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32112367

RESUMO

Lack of awareness of screening methods, risk factors, and symptoms may lead to late diagnosis and poor prognosis of cervical cancer. The plan of this study was to assess the level of awareness about cervical cancer and HPV vaccine among females of rural and urban areas of Haryana, India. This cross-sectional study was performed using a comprehensive self-designed questionnaire on 1500 women of urban (700) and rural (800) background aged 18-65 years, evaluating their knowledge for cervical cancer and screening, HPV infection and its preventive measure, and symptoms and risk factors. Data obtained was analyzed and interpreted by using simple percentages and bar charts. Most of the participants were aged between 21 and 30 years and had college level education. Majority of the women from rural areas had poor knowledge about cervical cancer (55%) and its screening (75%), HPV infection (87.5%), and HPV vaccine (95%) compared with urban areas. Knowledge about symptoms and risk factors was very low in both rural and urban areas. Whatever little knowledge the women had about cervical cancer was from college education, friends, neighbors, relatives, and medical practitioner or doctors. The survey pointed to the critical need to educate women about cervical cancer and its early diagnosis, related risk factors, symptoms, and preventive measures which can be achieved by launching extensive awareness programs for educating females about cervical cancer in India.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Adulto , Estudos Transversais , Detecção Precoce de Câncer , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Índia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/prevenção & controle , Inquéritos e Questionários , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Adulto Jovem
13.
Mol Biol Rep ; 47(12): 9725-9732, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33230782

RESUMO

Persistent infection with oncogenic HPV and downregulation of tumor suppressor genes play an essential role in the development and progression of cervical cancer. The present study aimed to identify the promoter methylation status of APC, SFRP1, and PTEN which are important regulators of Wnt pathway and their association with high-risk HPV infection and gene expression. Methylation Specific PCR (MSP) and quantitative reverse transcription PCR (RT-qPCR) were used to detect methylation status and gene expression levels of APC, SFRP1, and PTEN in cervical cancer biopsies (110) and paired non-cancerous biopsies (28). APC promoter was methylated in 38%, SFRP1 in 95%, and PTEN in 55% of the cervical cancer biopsies. Our data showed a trend of a higher rate of methylation of the gene promoters in cervical cancer biopsies while; they were majorly un-methylated in non-cancerous biopsies. Corresponding to a higher rate of methylation in cancer biopsies, the gene expression levels of APC, SFRP1, and PTEN were reduced in cervical cancer samples in comparison to normal cervix tissues. Further, we observed that 97% cancer biopsies were HPV infected and high-risk type HPV16 and 18 infections were significantly positively associated with APC (p = 0.008 and p = 0.007), SFRP1 (p = 0.003 and p = 0.0067), and PTEN (p = 0.049 and p = 0.008) promoter methylation. APC, SFRP1, and PTEN promoter hyper-methylation is positively associated with high-risk HPV infection and inversely associated with gene expression. Our findings show that high-risk HPV infection promotes methylation of these genes and further promotes their silencing.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , PTEN Fosfo-Hidrolase/genética , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/genética , Metilação de DNA , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Índia , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Neoplasias do Colo do Útero/etiologia
14.
Phys Chem Chem Phys ; 22(17): 9573-9586, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32322851

RESUMO

Synthesizing and understanding phase transition behavior of novel block copolymers is very crucial for fabricating next generation of smart materials with foreseeable applications. In this regard, we synthesized three random (r) copolymers of poly(N-vinyl-caprolactam) (PVCL) and poly(2-dimethyl amino ethyl methacrylate) (PDMAEMA) with varying percentages of each block and characterized them using nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) patterns, time-resolved fluorescence spectroscopy, and atomic force microscopy (AFM). Synthesized copolymers i.e. PVCL30-PDMAEMA70, PVCL50-PDMAEMA50 and PVCL70-PDMAEMA30 have fluorescence properties, which were confirmed by time-resolved fluorescence spectra and emission spectra, and emission bands were observed at ∼310, ∼435 and ∼424 nm, respectively. The fluorescence lifetime for PVCL50-PDMAEMA50 is larger than those of the other two copolymers suggesting a slow decay of the excited state. The copolymers have spherical geometry as micelles, which were confirmed by TEM. We observed patterned arrangement of micelles and the arranged micelles appear to be pentagon in shape, creating space in between the arranged micelles; however, for PVCL50-PDMAEMA50, the arranged micelles do not form any particular shape. The thermal phase transition of PVCL-r-PDMAEMA in aqueous solution was studied by differential scanning calorimetry and thermal fluorescence spectroscopy. In order to design a biomimetic polymer for bio-specific applications and to understand novel concepts towards polymer-protein interactions, we studied the effect of insulin on lower critical solution temperature (LCST) of PVCL-r-PDMAEMA using multiple sophisticated techniques. The LCST is finely tuned by incorporation of two blocks with various block compositions and the value falls within the range of human body temperature, making PVCL50-PDMAEMA50 a highly compatible material for bio-medical and bio-material applications. Insulin forms a self-assembly with the monomers of PVCL-r-PDMAEMA, which leads to enhancing the micellar aggregates and the eventual decrease in the LCST of the diblock copolymer aqueous solution. The present study provides new insights into insulin-copolymer interactions and can be used for self-assembling nanocarriers and designing protein resistance surfaces.


Assuntos
Insulina/química , Micelas , Conformação Molecular , Polímeros/química , Etilaminas/química , Metacrilatos/química , Multimerização Proteica
15.
Gynecol Endocrinol ; 35(11): 970-973, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31081410

RESUMO

One hundred and fifty infertile polycystic ovary syndrome (PCOS) women were classified into four phenotypes on the basis of Rotterdam criteria. Homeostatic model assessment of insulin resistance (HOMA-IR) with a cutoff ≥2.5 was considered as a measure of insulin resistance (IR). Maximum number of patients, 57 (38%) in our cohort belonged to phenotype A or the classical phenotype with all 3 features of Rotterdam criteria. Mean body mass index (BMI) in all phenotypes was more than 25 kg/m2 and the highest was seen in phenotype B. According to BMI categories in the four phenotypes, more number of women was in the obese category in phenotype A (24.5%) and B (56.5%) in comparison to phenotype C (18.2%) and D (10.8%) (p<.001). There was no difference in median HOMA-IR among different phenotype categories (p=.718). The median value of anti-mullerian hormone (AMH) was highest in phenotype A (11.68 ng/ml [7.94-16.46]) and significantly more in comparison to B phenotype (Kruskal-Wallis, p=.018). Thus there is heterogeneity in AMH levels and BMI in different PCOS phenotypes with higher levels in the most severe phenotypes. There is, however, no correlation of IR among the different phenotype groups and further investigation is needed to characterize its role in phenotypic classification.


Assuntos
Hormônio Antimülleriano/sangue , Índice de Massa Corporal , Resistência à Insulina , Síndrome do Ovário Policístico/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Fenótipo , Síndrome do Ovário Policístico/classificação , Síndrome do Ovário Policístico/epidemiologia , Síndrome do Ovário Policístico/fisiopatologia , Adulto Jovem
18.
Nat Prod Res ; 38(6): 1016-1023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37194669

RESUMO

A novel bioactive flavan glycoside was isolated by solvent extraction method with the help of Soxhlet apparatus from the methanolic extract of Tradescantia spathacea Sw. Flavan glycoside having molecular formula C20H22O10, melting point 175-1780C, molecular weight by ESI-MS m/z (M + H]+ 423, optical rotation was[α]21D-45.1(c 0.20 methanol). Its structure was determined (-)-epicatechin 7-O-alpha-L-arabinopyranoside. Various color reactions, chemical degradation (like acid hydrolysis, permethylation, and enzymatic hydrolysis), UV-Visible spectrophotometry, Fourier transforms infrared spectroscopy, electrospray ionization mass spectrometry, and nuclear magnetic resonance spectroscopy were used to establish the structure of compound (-)-(-)-epicatechin 7-O-alpha-L-arabinopyranoside.. A flavan glycoside was also tested with a DPPH assay method for antioxidant activity by using Ascorbic acid as standard. DPPH radical scavenging test data demonstrate that a flavan glycoside possesses potent antioxidant activity so this flavan glycoside can be utilized as a potent antioxidant agent.


Assuntos
Glicosídeos Cardíacos , Catequina , Commelinaceae , Tradescantia , Antioxidantes/farmacologia , Glicosídeos/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray
19.
Gene ; 919: 148501, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670395

RESUMO

HOX genes constitute a family of evolutionarily conserved transcription factors that play pivotal roles in embryonic development, tissue patterning, and cell differentiation. These genes are essential for the precise spatial and temporal control of body axis formation in vertebrates. In addition to their developmental functions, HOX genes have garnered significant attention for their involvement in various diseases, including cancer. Deregulation of HOX gene expression has been observed in numerous malignancies, where they can influence tumorigenesis, progression, and therapeutic responses. This review provides an overview of the diverse roles of HOX genes in development, disease, and potential therapeutic targets, highlighting their significance in understanding biological processes and their potential clinical implications.


Assuntos
Genes Homeobox , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/patologia , Animais , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Carcinogênese/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo
20.
J Phys Chem B ; 128(18): 4554-4565, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38683962

RESUMO

Deep eutectic solvents (DESs) have emerged as promising tools for crafting polymeric materials across diverse domains. This study delves into the impact of a series of DESs on the phase behavior of poly(N-isopropylacrylamide) (PNIPAM) in aqueous environments, presenting compelling insights into their performance. Specifically, we explore the conformational phase behavior of PNIPAM in the presence of four distinct lactic acid (LA)-based DESs: LA-betaine (LA-BET), LA-proline (LA-PRO), LA-choline chloride (LA-CC), and LA-urea (LA-U). By maintaining a consistent hydrogen-bond donor (HBD) while varying the hydrogen-bond acceptor (HBA), we unravel how different DES compositions modulate the phase transition behavior of PNIPAM. Our findings underscore the profound influence of DESs comprising LA as the HBD and diverse HBAs-BET, PRO, CC, and U on the thermoresponsive behavior of PNIPAM. Employing spectroscopic techniques such as ultraviolet-visible (UV-vis) spectroscopy, steady-state fluorescence, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), ζ-potential, and transmission electron microscopy (TEM), we elucidate the preferential interactions between the HBA groups within DESs and the hydration layer of PNIPAM. Notably, temperature-dependent DLS analyses reveal a discernible decrease in the lower critical solution temperature (LCST) of PNIPAM with increasing DES concentration, ultimately disrupting the hydrogen-bond interactions and resulting in early hydrophobic collapse of the polymer, which can be clearly seen in the TEM micrographs. Furthermore, the formation of polymer composites within the mixed system leads to notable alterations in the physiochemical properties of PNIPAM, as evidenced by shifts in its LCST value in the presence of DESs. This perturbation disrupts hydrogen-bond interactions, inducing hydrophobic collapse of the polymers, a phenomenon vividly captured in TEM micrographs. In essence, our study sheds new light on the pivotal role of varying HBA groups within DESs in modulating the conformational transitions of PNIPAM. These insights not only enrich our fundamental understanding but also hold immense promise for the development of smart polymeric systems with multifaceted applications spanning bioimaging, biomedical science, polymer science, and beyond.

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