ABSTRACT
In this article, the multifunctional behavior of novel, efficient, and cost-effective humic acid-coated nanoceria (HA@CeO2 NPs) was utilized for the sorptive removal of U(VI), Cr(VI), and F- ions at different conditions. The production cost of HA@CeO2 was $19.28/kg and was well characterized by DLS, FESEM, HRTEM, FTIR, XRD, XPS, and TGA. Batch adsorption study for U(VI) (at pH ~ 8), Cr(VI) (at pH ~ 1), and F- (at pH ~ 2) revealed that the maximum percentage of sorption was > 80% for all the cases. From the contact time experiment, it was concluded that pseudo-second-order kinetics followed, and hence, the process should be a chemisorption. The adsorption study revealed that U(VI) and Cr(VI) followed the Freundlich isotherm, whereas F- followed the Langmuir isotherm. Maximum adsorption capacity for F- was 96 mg g-1. Experiments in real water suggest that adsorption is decreased in Kaljani River water (~ 12% for Cr(VI) and ~ 11% for F-) and Kochbihar Lake water (25.04% for Cr(VI) and 20.5% for F-) because of competing ion effect. Mechanism was well established by the kinetic study as well as XPS analysis. Because of high adsorption efficiency, HA@CeO2 NPs can be used for the removal of other harmful water contaminants to make healthy aquatic life as well as purified drinking water.
ABSTRACT
U(vi) removal using cost-effective (production cost: $14.03 per kg), biocompatible, and superparamagnetic Cinnamomum tamala (CT) leaf extract-coated magnetite nanoparticles (CT@MNPs or CT@Fe3O4 nanoparticles) from water resources was studied. From pH-dependent experiments, the maximum adsorption efficiency was found to be at pH 8. Isotherm and kinetic studies were performed and found to follow Langmuir isotherm and pseudo-second order kinetics, respectively. The maximum adsorption capacity of CT@MNPs was calculated to be 45.5 mg of U(vi) per g of nanoparticles (NPs). Recyclability studies suggest that over 94% sorption was retained even after four consecutive cycles. The sorption mechanism was explained by the point of the zero-charge experiment and the XPS measurement. Additionally, calculations using density functional theory (DFT) were carried out to support the experimental findings.
ABSTRACT
The aim of the present study is to investigate the functional role of TNF-α single-nucleotide polymorphisms/haplotypes in an association with reproductive tract infections (RTIs) in symptomatic and asymptomatic women. A total of 850 consecutive subjects consisting of 400 cases and 450 healthy controls, were screened for RTIs, along with their risk factors and associated symptoms. The propensity score matching was performed to reduce the confounding bias arise owing to covariates and to balance the data between two groups. A total of 211 pairs (1:1) have been created. Genotyping of rs1800629 (-308) and rs361525 (-238) SNPs of TNF-α was done by PCR-RFLP followed by sequencing. The functional implication of TNF-α SNPs in an association with RTIs was also checked by using ELISA. The frequency of -238A allele and -308A allele was found to be twofold (P < 0.0001) and threefold (P < 0.0001) higher in the presence of RTIs. AA haplotype emerged as a major player in an association with RTIs and elevated TNF-α expression. The present study revealed the functional role of rs1800629 (-308) and rs361525 (-238) of TNF-α in an association with RTIs. This information may be used to establish biomarkers for an inflammatory response during the persistence of RTIs.
Subject(s)
Asian People/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Reproductive Tract Infections/epidemiology , Tumor Necrosis Factor-alpha/genetics , Adult , Case-Control Studies , Female , Genetic Association Studies , Genotype , Humans , India/epidemiology , Reproductive Tract Infections/genetics , Reproductive Tract Infections/pathologyABSTRACT
Phosphoramide functionalized Fe3O4 nanoparticles (NPs) were synthesized by a three step procedure and its application for uranium extraction from different enviornmental matrices has been demonstrated. A maximum adsorption capacity of 95.2â¯mg of U/g of the sorbent has been achieved which is higher as compared to many reported magnetic NPs. pH dependent adsorption studies were performed at 1â¯ppm uranium concentrations which suggests more than 80% adsorption in pH range of 4-8 with maximum adsorption at pH 6. Interestingly this is the pH range of most naturally occurring water bodies suggesting the potential of this material to extract uranium from real environmental samples. Adsorption studies were carried out with tap water, drinking water and sea water and more than 90% uranium extraction was observed. Desorption studies were performed with different reagents suggesting that the material can be reused again. EXAFS studies have been carried out which suggests that the uranium binds with oxygens of three PO group at the surface of phosphoramide functionalized NPs and based on this, binding mode of uranium with the synthesized sorbent is proposed.
ABSTRACT
Cervical cancer is one of the most common cancers among women in developing countries. Persistent infection with high-risk human papillomavirus (HPV) is the major determinant for the development of cervical cancer. Role of newly discovered T helper 9 (Th9) cells in cervical cancer pathogenesis is yet unfolded. In this study, we observed a huge infiltration of PU.1+ cells and overrepresentation of IL-9R in tissue biopsy specimens of CIN patients in cervical cancer cases. Treatment with Th9 signatory cytokines, IL-9 and IL-21, suppressed proliferation, enhanced apoptosis and stimulated the expression of MHC I and e-cadherin on HeLa cell lines. Th9 thus seems enhance antitumor immune response through T cell cytotoxicity and play crucial role in a controlling malignant cell transformation. Therefore, this study helps in firmer understanding of relevance of Th9 in cervical cancer immunity.
Subject(s)
Interleukin-9/metabolism , Papillomaviridae/physiology , Papillomavirus Infections/immunology , T-Lymphocytes, Helper-Inducer/immunology , Uterine Cervical Neoplasms/immunology , Cadherins/metabolism , Carcinogenesis , Female , HeLa Cells , Humans , Immune Evasion , Immunity, Cellular , Interleukins/metabolism , Receptors, Interleukin-9/genetics , Receptors, Interleukin-9/metabolism , Up-RegulationABSTRACT
BACKGROUND: Despite being most preventable malignancies associated with smoked and smokeless tobacco products, squamous cell carcinoma of oral cavity is one of the most common malignancy in India. The aim of the present study was to evaluate the role of TLRs in oral pre-cancerous, cancerous cases and their genotypic correlation with HPV/EBV, co-infection & lifestyle habits in Indian population. METHODS: The present study was conducted on 300 subjects (100 OSCC, 50 pre-cancer & 150 controls). The amplification of TLRs gene and HPV/EBV co-infection was assessed by Nested PCR, PCR-RFLP and further confirmation by direct sequencing. RESULTS: The TLR 9(-1486 T/C), revealed that the TT vs. CT + CC genotype had a Ë5-fold increased risk for the development of pre-cancerous lesions as compared to controls (p = 0.0001). Further analysis showed that the risk of cancer was extremely pronounced in HPV/EBV, co-infection (p = 0.0141), implicating the possible interaction between TLR 9(-1486T/C) genotype and HPV infection in increasing cancer/pre-cancer risk. The 'G' allele of TLR 4(+896A/G) was also a higher risk of developing pre-cancerous lesions with 4.5 fold and statistically significant (p = 0.0001). The genotypic association of TLR 9(-1486T/C) in OSMF cases showed Ë8 fold increased risk and TLR 4(+896A/G) showed fourteen fold higher risk for leukoplakia (p < 0.0001, OR = 14.000). CONCLUSION: Genetic polymorphism of TLR 9(-1486 T/C) and TLR 4(+896A/G) may influence the effects of HPV/EBV, co-infection and play the significant role in development of the disease. The significance of these TLRs seemed to be enhanced by tobacco chewing and smoking habits also, which act as an important etiological risk factor for OSCC.
Subject(s)
Coinfection/genetics , Epstein-Barr Virus Infections/genetics , Herpesvirus 4, Human/genetics , Mouth Neoplasms/etiology , Mouth Neoplasms/genetics , Nicotine/adverse effects , Polymorphism, Genetic/genetics , Adult , Asian People , Carcinoma, Squamous Cell/epidemiology , Female , Genetic Variation , Humans , India/epidemiology , Male , Middle Aged , Papillomavirus Infections/virology , Tobacco, Smokeless/adverse effectsABSTRACT
Background: Cervical cancer is the second major female cancer in India and constitutes one-fourth of the world's burden. Human Papilloma Virus (HPV) infection is an essential but insufficient cause for cervical cancer. Genetic variants in microRNAs (miRNAs/miRs) play an important role in the susceptibility of various types of cancers.Objective: To evaluate the association of Single Nucleotide Polymorphisms (SNPs) in miR-146a (rs2910164), miR-196a2 (rs11614913), and miR-499 (rs3746444), with cervical cancer susceptibility in Indian population.Methods: Three hundred samples were genotyped by Polymerase chain reaction (PCR)-Restriction fragment length polymorphism (RFLP). Both patients and controls were also screened for the presence of HPV DNA.Results: In this case-control study, 125 (83.3%) cervical cancer cases were found to be infected with HPV DNA. The frequency of miR-146a C allele was higher in controls than in cases [odds ratio (OR) (95% confidence interval (CI)) = 0.81 (0.57-1.14), P-value = 0.258]. miR-196a2 T allele was found to be associated with the decreased risk of cervical cancer [OR (95% CI) = 0.36 (0.26-0.50), P-value<0.0001]. Approximately 1.22-fold increased risk has been observed in individuals carrying miR-499 TT genotypes [OR (95% CI) = 1.22 (0.63-2.36), P-value = 0.617]. Interaction studies for miR-196a2/miR-499 loci showed that women carrying TT/CC and TT/CT genotypes were less likely to develop cervical cancer than CC/CC combination [P<0.05]. Likewise, miR-146a/miR-196a2 genotypic combinations (CC/TT, CG/TT, GG/TT) followed the similar trend [P<0.05], exhibited the protective effect against cervical cancer with reference to CC/CC group. Combined genotypes of miR-146a/miR-499 [CC/CT, CG/CC, CG/CT, CG/TT, GG/CC, GG/CT, GG/TT] demonstrated a non-significant trend toward higher cervical cancer risk [OR > 1.00, P>0.05].Conclusion: Polymorphisms in miR-146a, miR-196a2, and miR-499 individually or collectively have the prospective to emerge as biomarkers for cervical cancer.
Subject(s)
MicroRNAs/genetics , Polymorphism, Single Nucleotide , Uterine Cervical Neoplasms/genetics , Adult , Case-Control Studies , Female , Humans , India/epidemiology , Middle Aged , Uterine Cervical Neoplasms/epidemiologyABSTRACT
The correlation of interleukin 10 (IL-10) with the outbreak and progression of cancer has been well established as it contributes to tumor immune evasion. Convincing number of evidences has been accumulated to reflect the critical correlation between IL-10 polymorphism and tumorogenesis. Several polymorphic sites at promoter regions have been reported to be associated with cancer susceptibility. The purpose of this study was to examine the effect of modulated genotypes in the promoter region of IL-10 gene with life-style habits in oral squamous cell carcinoma (OSCC) in the Indian population. A total of 300 subjects (100 OSCC, 50 precancer and 150 healthy controls) were recruited in this study. The IL-10 promoter region was amplified in 14 overlapping fragments by PCR and further screened through the high throughput technique of denaturing high-performance liquid chromatography (dHPLC) followed by sequencing. We identified three novel variations at positions (-924, -1045 & -1066); we also found some known SNPs (-592C/A, -657G/A, -851G/A, -819C/T, -1082A/G). The identified novel variations were submitted to the NCBI Gene Bank (accession numbers KT153594, KT291742 and KT291743). We also noticed a significant association of polymorphisms (-592C/A, -819C/T and -1082A/G) individually as well as in combination (haplotypes) along with lifestyle habits for the risk of oral carcinoma (p<0.0001). We have reported three novel SNPs in the Indian population for the first time, and these SNPs may be associated with OSCC. Besides, we showed the first evidence of IL-10 haplotypes, i.e., CCG and CTG, may act as a biomarker for early detection of oral pre-cancerous/cancerous lesions or treatment management of oral carcinoma.
Subject(s)
Carcinoma, Squamous Cell/genetics , Interleukin-10/genetics , Mouth Neoplasms/genetics , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Adult , Aged , Carcinoma, Squamous Cell/pathology , Female , Humans , India , Male , Middle Aged , Mouth Neoplasms/pathologyABSTRACT
OBJECTIVE: Levels of proinflammatory (TNF A) and anti-inflammatory (IL-10) cytokines play a key role in the progression of inflammation as well as cancer disease. We were investigating the potential association of single-nucleotide polymorphisms (SNPs)/haplotypes in proinflammatory (TNF A) and anti-inflammatory (IL-10) cytokines locus with the development of PCa in Indian population. MATERIALS AND METHODS: We had genotyped 235 BPH/PCa samples (130 BPH and 105 cancer) along with 115 control samples for proinflammatory (TNF A -238G/A and -308G/A) and anti-inflammatory (IL-10 -1082A/G, -819C/T and -592C/A) cytokines SNPs in the gene promoter region using ARMS-PCR method. RESULTS: Allelic frequencies of TNF A and IL-10 SNPs were found to be significantly associated with the risk of prostate cancer and BPH when compared to controls (p = 0.05). Further haplotypic analysis showed that two haplotypes of TNF A (AG and AA) and IL-10 gene (CCG and CTG) were serving as risk haplotypes for prostate cancer development. IL-10 risk haplotypes were found to be positively associated with aggressiveness of prostate cancer. We also noticed successively increasing percentage of TNF A and IL-10 risk haplotypes with life style habits like smoking (10 and 26%) and alcohol consuming (9 and 27%). CONCLUSIONS: According to our data, TNF A -238G>A and IL-10 -1082A>G, -819C>T and -592C>A may be associated with the development of prostate cancer and BPH. We could also notice higher frequency of TNF A and IL-10 risk haplotypes in smoker and alcohol user. Interestingly, IL-10 risk haplotype was positively associated with aggressiveness of tumor. This information can be used for the early diagnosis of disease and to improve tissue-specific treatment's efficacy which will be moving ultimately towards the discovery of personalized therapy.
Subject(s)
Interleukin-10/genetics , Prostatic Hyperplasia/genetics , Prostatic Neoplasms/genetics , Tumor Necrosis Factor-alpha/genetics , Aged , Alcohol Drinking/genetics , Disease Progression , Haplotypes , Humans , India , Life Style , Male , Middle Aged , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Risk Factors , Smoking/genetics , White PeopleABSTRACT
Uranium is one of the most toxic and important elements present in the environment, and because of its high toxicity, ultra-trace-level detection is of utmost importance. Many methods were reported earlier for this purpose, but each has its own limitations such as high cost, sophisticated instrumentation, sample processing, and so forth. Herein we have demonstrated an alternate method that is much simpler and can be used for the ultra-trace-level detection of uranium. We have synthesized 3-mercaptopropionic acid (MPA)-capped CdSe/CdS core-shell quantum dots (CSQDs) and used its photoluminescence properties to detect uranium in solution. Steady-state emission studies suggest the luminescence quenching of CSQDs in the presence of uranium. Redox levels of CSQDs and uranium suggests that the electron-transfer process from photoexcited CSQDs to uranium is a thermodynamically viable process, which has subsequently been confirmed by time-resolved studies. A Stern-Volmer plot of CSQDs with uranium suggests that the detection limit of this method is 74.5 ppb. The method has an advantage over other reported methods for being simple and low cost and requiring a small amout of sample processing. To the best of our knowledge, we are reporting for the first time uranium detection using quasi-type II CSQDs and proposing the mechanistic path through luminescence spectroscopy, which in turn helps us to design an efficient detection method.
ABSTRACT
The present work describes the effect of interfacial complex formation on charge carrier dynamics in CdX (X=S, Se, Te) quantum dots (QDs) sensitized nitro catechol (NCAT). To compare experiments were also carried out with catechol (CAT) where no such complexation was observed. Time-resolved emission studies suggest faster charge separation in CdS(Se)/NCAT system as compared to CdS(Se)/CAT although change in Gibbs free energy for hole transfer is less in former as compared to later. This suggests that complex formation favours charge separation. Similar studies were also carried out in CdTe/NCAT system where hole transfer process was not viable thermodynamically but due to complex formation charge separation was observed. Femtosecond transient absorption studies have been carried out to monitor charge carrier dynamics in early time scale. Transient studies show faster electron cooling in QDs/NCAT system as compared to pure QDs and has been assigned to the complex formation on QDs surface. Interestingly charge recombination dynamics is much faster in QDs/NCAT system as compared to pure QDs which can be attributed to the stronger coupling between QDs and NCAT. Our results suggest a strong metal-ligand complex formation on QDs surface that controls charge carrier dynamics in QDs/molecular adsorbate system and to the best of our knowledge it has never been reported.
ABSTRACT
Considering the high toxicity and widespread availability of fluoride ions in different environmental matrices, it is imperative to design a probe for its detection. In view of this, a selective fluorescent on-off-on probe based on carbon quantum dots (CQDs) and Eu3+ has been designed. We have synthesized water-soluble carboxylic acid-functionalized CQDs and monitored their interaction with Eu3+. Luminescence quenching in the CQD emission was observed (switch-off) on adding Eu3+ ions. We investigate the reason for this luminescence quenching using time-resolved emission and high-resolution transmission electron microscopy (HRTEM) studies and observed that both electron transfer from CQDs to Eu3+ and aggregation of CQDs are responsible for the luminescence quenching. ζ-Potential and X-ray photoelectron spectroscopy studies confirm Eu3+ binding with the COOH groups on CQD surface. Interestingly, luminescence regains after the addition of fluoride ions to the CQDs/Eu3+ system (switch-on). This has been assigned to the removal of Eu3+ from the CQD surface due to the formation of EuF3 and is confirmed by X-ray diffraction and HRTEM measurements. The sensitivity of the probe was tested by carrying out experiments with other competing ions and was found to be selective for fluoride ions. Experiments with variable concentrations of fluoride ions suggest that the working range of the probe is 1-25 ppm. The probe has been successfully tested for the detection of fluoride ions in a toothpaste sample and the results were compared to those of ion chromatography. To the best of our knowledge, this is the first report based on CQDs and Eu3+ for the detection of fluoride ions, wherein a clear mechanism of the detection has been demonstrated, which, in turn, will help to develop better detection methods. The suggested probe is green, economical, rapid, efficient, and, most importantly, selective and can be used for the detection of fluoride ions in real environmental samples.
ABSTRACT
Uranium is one of the most toxic elements present in the environment and a number of methods have been developed for its extraction. Herein we have demonstrated a new method using magnetic nanoparticles (NPs) that can be used for uranium extraction from water and sea water matrix. Fe3O4 and humic acid (HA) coated Fe3O4 NPs with different amount of HA coating were synthesized and uranium sorption from water and sea water matrix was demonstrated. It was observed that sorption increases with increase in amount of HA coating. NPs settlement in presence of magnetic field was monitored where only bare Fe3O4 and Fe3O4/HA 1 NPs settles while no settlement was observed for Fe3O4/HA 2 and Fe3O4/HA 3 NPs. Considering both sorption and particle separation from the matrix Fe3O4/HA 1 NPs are the best among synthesized ones with maximum sorption capacity of 10.5mg of U/g of NPs. The results presented here reveal the exceptional potential of magnetic NPs and functionalized magnetic NPs for environmental remediation of uranium and to extract uranium from sea water on which to the best of our knowledge no report is available till now.
ABSTRACT
BACKGROUND AND OBJECTIVES: To investigate a potential association between single-nucleotide polymorphisms (SNPs) and haplotypes at the TNFA-LTA locus and the development of oral cancer in an Indian population. MATERIALS AND METHODS: In this study, 150 oral precancer/cancer samples (50 precancer and 100 cancer), along with an equal number of control samples, were genotyped. Six SNPs at the TNF-LTA locus (i.e., -238G/A, -308G/A, -857C/T, -863C/A, -1031T/C, and +252A/G) were analyzed by use of a polymerase chain reaction-restriction fragment length polymorphism method, the assay was validated by sequencing 10 % of samples. RESULTS: The allelic frequencies of TNFA and LTA SNPs were found to be significantly associated with the risk of oral cancer and precancerous lesions in comparison with controls (P < 0.0003). Further haplotypic analysis showed that two haplotypes (ATCTGG and ACACGG) served as risk haplotypes for oral cancer. These haplotypes were also found to be significantly and positively associated with lifestyle habits (tobacco chewing P = 0.04, odds ratio [OR] 3.4) and socioeconomic status (P = 0.01, OR 3.4). We noticed an increased percentage of risk haplotypes correlating with the aggressiveness of oral cancer. The percentages of risk haplotypes were found to be threefold higher in precancer and fourfold higher in advanced stages of oral cancer in comparison with controls. CONCLUSION: Five SNPs at the TNF-LTA locus (i.e., -308G>A, -857C>T, -863C>A, -1031T>C, and +252A>G) were found to be associated with the development of oral cancer. Two haplotypes (ATCTGG and ACACGG) emerged as major risk haplotypes for oral carcinoma progression and were also found to be associated with lifestyle factors and clinical aggressiveness. These findings make the TNF-LTA locus a suitable candidate for a future biomarker, which may be used either for early detection or for helping to improve treatment efficacy and effectiveness.
Subject(s)
Carcinoma/genetics , Life Style , Lymphotoxin-alpha/genetics , Mouth Neoplasms/genetics , Polymorphism, Single Nucleotide , Tumor Necrosis Factor-alpha/genetics , Adult , Alleles , Carcinoma/epidemiology , Carcinoma/etiology , Case-Control Studies , Disease Progression , Female , Gene Frequency , Genotype , Haplotypes , Humans , India/epidemiology , Male , Middle Aged , Mouth Neoplasms/epidemiology , Mouth Neoplasms/etiology , Odds Ratio , Risk Factors , Social ClassABSTRACT
Cervical cancer is one of the most common malignancies among women in India. Beside HPV, other factors present in host also put their role in the progression of cervical tumerogenesis. In present study, we screened 300 subjects to identify variations in TNFR2 gene by PCR-dHPLC method followed by direct sequencing. We identified six known and four novel variations in six different exons of TNFR2 gene. Out of these identified variations, five known variations were found to be significantly associated with the risk of cervical cancer (p < 0.0001). On construction of haplotypes, one haplotype (TTGCC) was emerged as a major protective type while two (CAAGC + CTGCC) were revealed as major risk haplotypes. In conclusion, postmenopausal women having CAAGC + CTGCC haplotypes in TNFR2 gene along with HPV infection and tobacco consumption may lead to the development of cervical cancer.
Subject(s)
Genetic Variation/genetics , Receptors, Tumor Necrosis Factor, Type II/genetics , Uterine Cervical Neoplasms/genetics , Adult , Female , Genetic Predisposition to Disease , Haplotypes , Humans , India , Papillomaviridae/pathogenicity , Postmenopause , Tobacco Use/adverse effects , Uterine Cervical Neoplasms/etiologyABSTRACT
This study aimed to investigate the role of miRNAs in HPV-mediated cervical pre-cancer and cancer cases in Indian population. We analysed the HPV infection and its genotypes in uterine cervical pre-cancer (n = 80), cancer (n = 200) and normal cervical samples (n = 150) by consensus sequence PCR followed by type specific PCRs. Also, microRNA profiling was done in a subset of cervical pre-cancer (n = 20), cancer cases (n = 50) and normal samples (n = 30) by real-time quantitative PCR (qRT-PCR). The prevalence of HPV infection in pre-cancer was found to be 81 % (65/80) and 94 % (188/200) in cancer cases, with most predominant high-risk HPV type-16 (HR-HPV-16) in 83 % of cancer and 91 % of pre- cancer cases, respectively. Whereas in controls, the HPV infection was found to be very low (5 %). The miRNA profiling revealed that in cervical pre-cancer, 100 miRNAs were significantly (p < 0.001) differentially expressed with 70 miRNAs upregulated and 30 miRNAs downregulated. In cervical cancer cases, 383 miRNA were found to be differentially expressed (p < 0.001), of which 350 miRNAs were upregulated and 33 miRNAs were downregulated. We also observed that 182 miRNAs were differentially expressed (p < 0.001) in HPV-16/18-positive (SiHa/HeLa) cell lines compared with HPV-negative (C33A) cell line. In addition, we identified the novel microRNAs such as miR-892b, miR-500, miR-888, miR-505 and miR-711 in cervical precancerous lesions and cervical cancer cases in Indian population. Taken together, the study demonstrates a crucial role of microRNAs in cervical cancer, which may serve as potential early diagnostic markers for cervical carcinogenesis.
Subject(s)
Biomarkers, Tumor/metabolism , MicroRNAs/metabolism , Papillomavirus Infections/metabolism , Uterine Cervical Dysplasia/metabolism , Uterine Cervical Neoplasms/metabolism , Biomarkers, Tumor/genetics , Carcinogenesis/genetics , Carcinogenesis/metabolism , Case-Control Studies , Down-Regulation , Early Detection of Cancer , Female , Gene Expression Regulation, Neoplastic , HeLa Cells , Humans , MicroRNAs/genetics , Papillomavirus Infections/diagnosis , Papillomavirus Infections/genetics , Papillomavirus Infections/virology , Squamous Intraepithelial Lesions of the Cervix/diagnosis , Squamous Intraepithelial Lesions of the Cervix/genetics , Squamous Intraepithelial Lesions of the Cervix/metabolism , Squamous Intraepithelial Lesions of the Cervix/virology , Transcriptome , Up-Regulation , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Dysplasia/genetics , Uterine Cervical Dysplasia/virologyABSTRACT
The present work describes ultrafast thermalized and hot hole transfer processes from photo-excited CdSe quantum dots (QDs) and CdSe/ZnS core-shell QDs (CSQDs) to newly synthesized thiols. Three thiols namely 2-mercapto-N-phenylacetamide (AAT), 3-mercapto-N-phenylpropanamide (APT) and 3-mercapto-N-(4-methoxyphenyl) propanamide (ADPT) were synthesized and their interaction with both CdSe QDs and CdSe/ZnS CSQDs was monitored. Steady state absorption study suggests the exciton delocalization from CdSe QDs in the presence of the thiols. However similar features were not observed in the presence of a ZnS shell over a CdSe core, instead a broadening in the excitonic peak was observed with both APT and ADPT but not with AAT. This exciton delocalization and broadening in the excitonic peak was also confirmed by ultrafast transient absorption studies. Steady state and time resolved emission studies show hole transfer from photo-excited QDs and CSQDs to the thiols. A signature of hot hole extraction was observed in transient absorption studies which was confirmed by fluorescence upconversion studies. Both hot and thermalized hole transfer rates from CdSe QDs and CdSe/ZnS CSQDs to the thiols were determined using the fluorescence up-conversion technique. Experiments with different ZnS shell thicknesses have been carried out which suggest that hole transfer is possible till 2.5 monolayer of the ZnS shell. To the best of our knowledge we are reporting for the first time the extraction of hot holes from CdSe/ZnS type I CSQDs by a molecular adsorbate.
ABSTRACT
Ultrafast thermalized and hot-hole-transfer processes have been investigated in CdSe quantum dot (QD)/catechol composite systems in which hole transfer from photoexcited QDs to the catechols is thermodynamically favorable. A series of catechol derivatives were selected with different electron-donating and -withdrawing groups, and the effect of these groups on hole transfer and charge recombination (CR) dynamics has been investigated. The hole-transfer time was determined using the fluorescence upconversion technique and found to be 2-10â ps depending on the molecular structure of the catechol derivatives. The hot-hole-transfer process was followed after monitoring 2S luminescence of CdSe QDs. Interestingly, hot-hole extraction was observed only in the CdSe/3-methoxycatechol (3-OCH3) composite system owing to the higher electron-donating property of the 3-methoxy group. To confirm the extraction of the hot hole and to monitor the CR reaction in CdSe QD/catechol composite systems, ultrafast transient absorption studies have been carried out. Ultrafast transient-absorption studies show that the bleach recovery kinetics of CdSe QD at the 2S excitonic position is much faster in the presence of 3-OCH3. This faster bleach recovery at the 2S position in CdSe/3-OCH3 suggests hot-hole transfer from CdSe QD to 3-OCH3. CR dynamics in CdSe QD/catechol composite systems was followed by monitoring the excitonic bleach at the 1S position and was found to decrease with free energy of the CR reaction.
Subject(s)
Quantum Dots/chemistry , Catechols , Electrons , Molecular StructureABSTRACT
AIM: Cervical cancer is the most common gynecological malignancy in the developing countries like India. In addition to human papillomavirus (HPV) infection, host genetic factors play an important role in viral persistence and neoplastic growth. IL-10, a multifunctional cytokine, plays an active role to promote tumor growth in the presence of HPV. The present study aims to find out the impact of IL-10 promoter polymorphisms at -1082A/G (rs1800896), -819C/T (rs1800872), and -592C/A (rs1800871) sites along with IL-10 production and HPV infection in the progression of cervical cancer. METHODS: We have genotyped a total of 506 subjects, 256 cases (208 cervical cancer + 48 precancer), and 250 healthy controls by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method followed by sequencing. IL-10 serum concentration was measured by enzyme-linked immunosorbent assay. RESULTS: The frequency of IL-10 -592 variant genotype (AA) was found significantly reduced in cases as compare to controls while -1082 variant genotype (GG) was found ~4-fold higher risk of cervical cancer (p = <0.0001, OR = 3.667, 95% CI = 2.329-5.773). On construction of haplotypes, GTC haplotype was emerged as a major risk haplotype while ACA haplotype was seemed as a marker for precancerous lesions. IL-10 serum concentration was observed higher in HPV-infected precancer and cancer cases. GTC haplotype was found to be coupled with higher serum concentration of IL-10 and HPV infection. CONCLUSION: IL-10 polymorphisms play a role in cervical cancer development and that GTC haplotype, which is closely related to its serum concentration, maybe a useful biomarker for HPV-mediated cervical cancer.