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1.
Chemosphere ; 352: 141418, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38340994

ABSTRACT

In this study, we are reporting for the first time the utilization of Solanum tuberosum tuber-driven, starch-mediated, green-hydrothermally synthesized cerium oxide nanoparticles (G-CeO2 NPs) for the antibacterial activity and photodegradation of cationic (methylene blue, MB) and anionic (methyl orange, MO) dyes separately and in combination, aimed at environmental remediation. The XRD analysis confirms the fluorite structure of G-CeO2 NPs, displaying an average crystallite size of 9.6 nm. Further, XPS confirms the existence of 24% of Ce3+ oxidation states within G-CeO2 NPs. Morphological studies through FE-SEM and TEM reveal that starch-driven OH- ion production leads to a high percentage of active crystal facets, favoring the formation of Ce3+-rich CeO2 NPs. Photocatalytic experiments conducted under UV-A illumination demonstrate the superior degradation performance of G-CeO2 NPs, with MB degradation reaching 93.4% and MO degradation at 77.2% within 90 min. This outstanding catalytic activity is attributed to the mesoporous structure (pore diameter of 5.63 nm) with a narrow band gap, a large surface area (103.38 m2g-1), and reduced charge recombination, as validated by BET, UV-visible, and electrochemical investigations. The identification of photogenerated intermediates is achieved through LCMS, while the mineralization is monitored via total organic carbon analysis. Moreover, the scavenging experiments point towards the involvement of reactive oxygen species in organic oxidation, demonstrating efficiency over five consecutive trials. Additionally, G-CeO2 NPs exhibit potent antibacterial activity against both gram-positive and gram-negative bacteria. This study presents an innovative, and efficient approach to environmental remediation, shedding light on the potential of G-CeO2 NPs in addressing environmental pollution challenges.


Subject(s)
Cerium , Nanoparticles , Solanum tuberosum , Anti-Bacterial Agents/chemistry , Gram-Negative Bacteria , Gram-Positive Bacteria , Nanoparticles/chemistry , Cerium/pharmacology , Cerium/chemistry
2.
3 Biotech ; 13(5): 147, 2023 May.
Article in English | MEDLINE | ID: mdl-37124988

ABSTRACT

Carbon in many different forms especially, Graphene, Carbon nanotubes (CNTs), and Fullerene is emerging as an important material in the areas of the biomedical field for various applications. This review comprehensively describes the nano antibiotic effect of carbon-based nanocomposites: epicenter on graphene, carbon nanotubes, and fullerene Composites. It summarises the studies conducted to evaluate their antimicrobial applications as they can disrupt the cell membrane of bacteria resulting in cell death. The initial section gives a glimpse of both "Gram"-positive and negative bacteria, which have been affected by Graphene, CNTs, and Fullerene-based nanocomposites. These bacteria include Staphylococcus Aureus, Bacillus Thuringiensis, Enterococcus faecalis, Enterococcus faecium, Bacillus subtilis, Escherichia coli, Klebseilla pneumoniae, Pseudomonas aeroginosa, Pseudomonas syringae , Shigella flexneri,Candida Albicans, Mucor. Another section is dedicated to the insight of Graphene, and its types such as Graphene Oxide (GO), Reduced graphene oxide (rGO), Graphene Nanoplatelets (GNPs), Graphene Nanoribbons (GNRs), and Graphene Quantum Dots (GQDs). Insight into CNT, including both the types SWCNT and MWCNT, studied, followed by understanding fullerene is also reported. Another section is dedicated to the antibacterial mechanism of Graphene, CNT, and Fullerene-based nanocomposites. Further, an additional section is dedicated to a comprehensive review of the antibacterial characteristics of Graphene, CNT, and nanocomposites based on fullerene. Future perspectives and recommendations have also been highlighted in the last section.

3.
J Mater Chem B ; 10(41): 8478-8489, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36197135

ABSTRACT

The outbreak of the highly contagious disease COVID-19, which is triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), demands a rapid, low-cost, and highly sensitive immunosensor that can detect and identify the virus efficiently. Here, an electrochemical immunosensor based on a nanocomposite consisting of molybdenum disulfide nanosheets decorated with polydopamine (MoS2-PDA) is developed for highly sensitive detection of SARS-CoV-2 nucleocapsid protein (N protein). The MoS2-PDA nanocomposite possesses various hydroxyl and amine groups that have excellent chemistry with crosslinkers and act as adhesive agents to bind with the working electrode surface. Furthermore, the optical, functional, structural, vibrational, and morphological properties of the MoS2-PDA nanocomposite are studied using various characterization techniques such as UV-vis, FTIR, and Raman spectroscopies, XRD, and TEM. The electrochemical immunosensor is fabricated by functionalizing the MoS2-PDA nanocomposite with anti-SARS-CoV-2 nucleocapsid IgG antibody (Ab) and has a very high sensitivity against the N protein with a linear range between 10 ag mL-1 and 100 ng mL-1. The electrochemical immunosensor exhibits a lowest limit of detection (LOD) of 2.80 ag mL-1 and a limit of quantification (LOQ) of 8.48 ag mL-1via electrochemical impedance spectroscopy (EIS). Furthermore, the electrochemical immunosensor is successfully employed to detect the N protein in nasopharyngeal swab specimens and displays good consistency with the conventional RT-PCR test results. The results show that the MoS2-PDA nanocomposite-based electrochemical platform can serve as a highly sensitive and selective detector of N protein and will pave the way for the development of a point-of-care (POC) electrochemical immunosensor for rapid detection of other infectious viruses.


Subject(s)
Biosensing Techniques , COVID-19 , Humans , Molybdenum/chemistry , Biosensing Techniques/methods , Electrochemical Techniques/methods , Immunoassay , SARS-CoV-2 , COVID-19/diagnosis , Immunoglobulin G , Amines
4.
Phys Chem Chem Phys ; 24(32): 19164-19176, 2022 Aug 17.
Article in English | MEDLINE | ID: mdl-35943087

ABSTRACT

The development of efficient electrochemical sensors of exceptional features, molecularly imprinted polymers (MIPs), has been extensively utilized due to their great vitality as an alternative to bio-recognition elements. MIPs as an artificial bio-recognition element are getting significant attention due to their affordability, easy processability, and scaling-up capabilities. However, the challenge of longer stability and higher sensitivity associated with MIP-based sensing technology is still a remaining challenge. This can be addressed by modifying MIPs with electro-active nano-systems. Correspondingly, MXene is an emerging material of choice to make MIP-based sensing platforms more efficient and develop a bio-active-free sensing system. This review highlights state-of-the-art MXene-modified MIP electrochemical sensing platforms to overcome the associated limitations of pristine MIPs. As a proof-of-concept, the sensitive and selective detection of markers for health monitoring can be efficiently fulfilled by the high-performance MXene-MIP nanocomposite-based electrochemical sensor. Moreover, the challenges associated with this research area along with the potential solutions are also discussed. An attempt has been made to explore MXene-MIP nanocomposites as a next-generation sensing platform suitable for point-of-care testing (POCT) applications.


Subject(s)
Molecular Imprinting , Nanocomposites , Molecularly Imprinted Polymers , Polymers
5.
Mater Today Chem ; 18: 100385, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33106780

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new virus in the coronavirus family that causes coronavirus disease (COVID-19), emerges as a big threat to the human race. To date, there is no medicine and vaccine available for COVID-19 treatment. While the development of medicines and vaccines are essentially and urgently required, what is also extremely important is the repurposing of smart materials to design effective systems for combating COVID-19. Graphene and graphene-related materials (GRMs) exhibit extraordinary physicochemical, electrical, optical, antiviral, antimicrobial, and other fascinating properties that warrant them as potential candidates for designing and development of high-performance components and devices required for COVID-19 pandemic and other futuristic calamities. In this article, we discuss the potential of graphene and GRMs for healthcare applications and how they may contribute to fighting against COVID-19.

6.
Ann Card Anaesth ; 23(2): 189-192, 2020.
Article in English | MEDLINE | ID: mdl-32275034

ABSTRACT

Background: Cardiac output (CO) assessment is a corner stone in advanced haemodynamic management, especially in critical ill patients. The present study was conducted to validate cardiac index and cardiac output by NICaS™ with the thermodilution technique using pulmonary artery catheter in post-operative cardiac surgical patients. Materials and Methods: This was a prospective observational clinical study conducted at a tertiary care hospital. 23 adult patients in the age range of 18-65 years who had undergone for elective coronary artery bypass grafting were included in the study. Results: Spearman's correlation coefficient of cardiac index between continuous Thermodilution (cTD) and Non-Invasive Cardiac System (NICaS™) showed a good correlation (r = 0.765, 95% confidence interval 0.70 to 0.82, P < 0.0001). There was a good correlation between cTD and NICaS™ for cardiac output (r = 0.759, 95% confidence interval 0.69 to 0.81, P < 0.0001), Bland-Altman plot for cardiac index between cTD and NICaS™ showed a mean bias of -0.66 ± 0.6919 with limits of agreement being -2.02 to 0.6936. Bland-Altman plot for cardiac output between cTD and NICaS™ showed a mean bias of -1.0386 ± 1.17 with limits of agreement being -3.34 to + 1.26. Percentage error for cardiac index and cardiac output were 64.78% and 64% respectively. Polar plot analysis showed an angular bias of 6.32° with radial limits of agreement being -8.114° to 20.75° for cardiac index and angular bias of 5.6682° with radial limits of agreement being -9.1422° to 20.4784° for cardiac output. Conclusion: NICaS™ demonstrated a good trending ability for both CI and CO. However, NICaS™ derived parameters are not interchangeable with the values derived from continuous thermodilution technique.


Subject(s)
Cardiac Output/physiology , Cardiac Surgical Procedures , Cardiography, Impedance/methods , Monitoring, Intraoperative/methods , Adolescent , Adult , Aged , Catheterization, Swan-Ganz , Female , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Thermodilution , Young Adult
7.
Ann Card Anaesth ; 21(3): 333-338, 2018.
Article in English | MEDLINE | ID: mdl-30052231

ABSTRACT

BACKGROUND: Good postoperative analgesia in cardiac surgical patients helps in early recovery and ambulation. An alternative to parenteral, paravertebral, and thoracic epidural analgesia can be pectoralis nerve (Pecs) block, which is novel, less invasive regional analgesic technique. AIMS: We hypothesized that Pecs block would provide superior postoperative analgesia for patients undergoing cardiac surgery through midline sternotomy compared to parenteral analgesia. MATERIALS AND METHODS: Forty adult patients between the age groups of 25 and 65 years undergoing coronary artery bypass grafting or valve surgeries through midline sternotomy under general anesthesia were enrolled in the study. Patients were randomly allocated into two groups with 20 in each group. Group 1 patients did not receive Pecs block, whereas Group 2 patients received bilateral Pecs block postoperatively. Patients were extubated once they fulfilled extubation criteria. Ventilator duration was recorded. Patients were interrogated for pain by visual analog scale (VAS) scoring at rest and cough. Inspiratory flow rate was assessed using incentive spirometry. RESULTS: Pecs group patients required lesser duration of ventilator support (P < 0.0001) in comparison to control group. Pain scores at rest and cough were significantly low in Pecs group at 0, 3, 6, 12, and 18 h from extubation (P < 0.05). At 24 h, VAS scores were comparable between two groups. Peak inspiratory flow rates were higher in Pecs group as compared to control group at 0, 3, 6, 12, 18, and 24 h (P < 0.05). Thirty-four episodes of rescue analgesia were given in control group, whereas in Pecs group, there were only four episodes of rescue analgesia. CONCLUSION: Pecs block is technically simple and effective technique and can be used as part of multimodal analgesia in postoperative cardiac surgical patients for better patient comfort and outcome.


Subject(s)
Cardiac Surgical Procedures/methods , Nerve Block , Pain, Postoperative/drug therapy , Thoracic Nerves , Adult , Aged , Analgesia, Patient-Controlled , Coronary Artery Bypass , Cough/complications , Cough/physiopathology , Female , Heart Valve Prosthesis Implantation , Humans , Male , Middle Aged , Pain Measurement , Respiration, Artificial , Spirometry , Sternotomy
8.
Saudi J Anaesth ; 11(1): 89-92, 2017.
Article in English | MEDLINE | ID: mdl-28217062

ABSTRACT

Gilbert's syndrome (GS) is an autosomal inherited disorder characterized by relative deficiency of glucuronyl transferase and poor uptake of unconjugated bilirubin by hepatocytes. Cardiac surgery on cardiopulmonary bypass (CPB) in these patients triggers further hepatic dysfunction. Transesophageal echocardiography (TEE) and Doppler assessment of hepatic vein help in assessing hepatic blood flow (HBF) during cardiac surgery. Here, we discuss anesthetic management and role of TEE in maintaining HBF perioperatively in a 25-year-old male patient with GS undergoing double valve replacement with tricuspid valve plasty. TEE-guided HBF monitoring and management of hepatic perfusion by modifying anesthetic and CPB protocol resulted in the favorable outcome.

9.
Ann Card Anaesth ; 19(3): 394-8, 2016.
Article in English | MEDLINE | ID: mdl-27397441

ABSTRACT

INTRODUCTION: Dexmedetomidine is an alpha-2 agonist used for conscious sedation. It has also been shown to have a myocardial protective effect in off-pump coronary artery bypass patients. The aim of the study was to assess the effect of dexmedetomidine for myocardial protection in percutaneous coronary interventional patients. METHODOLOGY: A total of 60 patients (group dexmedetomidine, n = 30 and group normal saline, n = 30) were enrolled in the study. Dexmedetomidine infusion (1 mcg/kg) over 15 min was given as a loading dose after coronary angiography in group dexmedetomidine (D) while normal saline was given in the control group (C) and later maintenance infusion was started at 0.5 mcg/kg/h in both the groups. Coronary vessel diameter was noted before (T0) and after (T1) loading dose of dexmedetomidine/saline in each group. Troponin T (Trop T) values were noted at baseline (T0), 6 h (T2), 12 h (T3) and 24 h (T4) after starting the loading dose. Hemodynamic variables (heart rate [HR] and blood pressure) were monitored at T0, T1, and at regular intervals till 2 h postprocedure. RESULTS: Coronary vessel diameter and HR significantly decreased in group D as compared to control group (P < 0.05) whereas the decrease in Trop T at 6 h, 12 h, and 24 h were not statistically significant between the two groups. CONCLUSION: Dexmedetomidine decreases the coronary vessel diameter, but maintains the myocardial oxygen demand-supply ratio by decreasing the HR. The decrease in Trop T is statistically insignificant at the doses used.


Subject(s)
Coronary Vessels/drug effects , Dexmedetomidine/pharmacology , Heart/drug effects , Percutaneous Coronary Intervention , Adult , Female , Humans , Hypnotics and Sedatives/pharmacology , Male , Middle Aged
10.
Ann Card Anaesth ; 19(3): 405-9, 2016.
Article in English | MEDLINE | ID: mdl-27397443

ABSTRACT

INTRODUCTION: Central venous pressure (CVP) measurement is essential in the management of certain clinical situations, including cardiac failure, volume overload and sepsis. CVP measurement requires catheterization of the central vein which is invasive and may lead to complications. The aim of this study was to evaluate the accuracy of measurement of CVP using a new noninvasive method based on near infrared spectroscopy (NIRS) in a group of cardiac surgical Intensive Care Unit (ICU) patients. METHODOLOGY: Thirty patients in cardiac surgical ICU were enrolled in the study who had an in situ central venous catheter (CVC). Sixty measurements were recorded in 1 h for each patient. A total of 1800 values were compared between noninvasive CVP (CVPn) obtained from Mespere VENUS 2000 CVP system and invasive CVP (CVPi) obtained from CVC. RESULTS: Strong positive correlation was found between CVPi and CVPn (R = 0.9272, P < 0.0001). Linear regression equation - CVPi = 0.5404 + 0.8875 × CVPn (r2 = 0.86, P < 0.001), Bland-Altman bias plots showed mean difference ± standard deviation and limits of agreement: -0.31 ± 1.36 and - 2.99 to + 2.37 (CVPi-CVPn). CONCLUSION: Noninvasive assessment of the CVP based on NIRS yields readings consistently close to those measured invasively. CVPn may be a clinically useful substitute for CVPi measurements with an advantage of being simple and continuous. It is a promising tool for early management of acute state wherein knowledge of CVP is helpful.


Subject(s)
Cardiac Surgical Procedures , Catheterization, Central Venous/methods , Central Venous Pressure/physiology , Critical Care/methods , Monitoring, Physiologic/methods , Spectroscopy, Near-Infrared/methods , Adolescent , Adult , Aged , Female , Humans , Intensive Care Units , Male , Middle Aged , Reproducibility of Results , Young Adult
11.
Vet Parasitol Reg Stud Reports ; 5: 37-41, 2016 Sep.
Article in English | MEDLINE | ID: mdl-31014536

ABSTRACT

The present communication deals with the detection and characterization of deltamethrin resistance in tick populations using biological (larval packet test), biochemical (esterase enzyme assay) and molecular assays. Ticks were collected from cattle farms of Korutla, Telangana (KOR), Mehboob Nagar, Telangana (MBN), Nagpur, Maharashtra (NAG), Parbani, Maharashtra (PBN), Madhavaram, Tamil Nadu (MAD), Cuddalore, Tamil Nadu (CUD), Sakhleshpur, Karnataka (SAK) and Buvenduvella, Karnataka (BUV). Out of eight field isolates, seven were identified as Rhipicephalus (Boophilus) microplus while one isolate (CUD) was identified as R. (B.) annulatus. The LC50 values and resistance factors (RF) of field isolates were assessed by larval packet test (LPT). RF values of two isolates viz., Korutla and Parbhani (KOR, PAR) were close to that of reference susceptible isolate. R. (B.) microplus isolate from Nagpur (NAG) and Sakleshpur (SAK) revealed slightly higher RF values (6.42 and 4.51). They revealed slightly elevated esterase enzyme activity too. Other isolates did not reveal higher values for RF or esterase activity. Previously identified mutations conferring synthetic pyrethroid resistance in R. (B.) microplus populations were analysed by sequencing the mutation flanking regions of the carboxyl esterase and the sodium channel genes (domain III S6 and domain II S4-5 linker region). However, these point mutations were not detected in the field isolates. The results of the present study revealed that low levels of synthetic pyrethroid resistance had developed in field populations of ticks of southern India.

12.
Pak J Biol Sci ; 17(1): 41-8, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24783776

ABSTRACT

Presence of polyphenolic content in various part of the plant exhibit wide pharmacological activities including antioxidant activity. The present study was designed to evaluate the phenolic contents (total phenols, flavonoid and tannins) and antioxidant properties of ethanolic extracts of flower, leaf, pod, bark and root obtained from Cassia auriculata. Ethanolic extracts of various parts of C. auriculata obtained by sonication extraction techniques are studied for their phenolic contents and DPPH (2,2-diphenyl-1-picrylhydrazine) radical scavenging assay as well as total antioxidant assays using UV visible spectrophotometer. Among the various parts of the plant studied, bark showed significant content of phenolics, flavonoids and tannins followed by the root, leaf, flower and pod. Even bark extract exhibited highest antioxidant capacity in DPPH assay followed by root, leaf, flower and pod with a value of 766.7, 679.3, 644.9, 572.5 and 474.7 mg vitamin C equivalent antioxidant capacity (mg VCEAC)/sample, respectively. In addition, mg VCEAC values obtained from the total antioxidant assay was in the increasing order of bark > root > leaf > flower > pod. Moreover, a strong correlation was also found between phenolic contents and antioxidant values indicating their influence in the found antioxidant activity, hence the bark extract can be employed as an ideal candidate for herbal based pharmaceutical product. Results of the present study also emphasize variation in the chemical composition as well as biological activity ensuring the importance of proper selection of particular part of the plant to evaluate their therapeutic potency.


Subject(s)
Cassia/chemistry , Free Radical Scavengers/analysis , Free Radical Scavengers/pharmacology , Medicine, Traditional , Phenols/analysis , Phenols/pharmacology , Plant Structures/chemistry , Tannins/analysis , Tannins/pharmacology
13.
J Dent Res ; 93(7 Suppl): 29S-36S, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24663683

ABSTRACT

Human papillomavirus (HPV) is known to be associated with several types of human cancer, including cervical, vulvar, vaginal, penile, anal, and head-and-neck cancers. Among these cancers, HPV-associated head-and-neck cancers, inclusive of oropharyngeal squamous cell carcinoma (OSCC) and oral cavity squamous cell carcinomas (OCSCC), have recently risen dramatically in men under 50 years old. Within 20 years, the percentage of HPV-positive OSCC in total OSCC went from less than 20% to more than 70% in the United States and some European countries. This article reviews the incidence trend and pathogenesis of HPV-associated head-and-neck cancers as well as current treatment modalities for the disease.


Subject(s)
Alphapapillomavirus/physiology , Carcinoma, Squamous Cell/virology , Mouth Neoplasms/virology , Papillomavirus Infections/virology , Carcinoma, Squamous Cell/therapy , Cell Transformation, Viral/physiology , Head and Neck Neoplasms/therapy , Head and Neck Neoplasms/virology , Humans , Molecular Targeted Therapy , Mouth Neoplasms/therapy , Papillomavirus Infections/therapy
15.
Med J Malaysia ; 65(3): 204-8, 2010 Sep.
Article in English | MEDLINE | ID: mdl-21939169

ABSTRACT

Caesarean section is a common operation and the best postoperative outcomes are desired. Surgical techniques have been devised or modified to reduce operative and post operative discomfort. Many studies have evaluated or compared the Joel-Cohen abdominal incision with Pfannenstiel incision and found the former to be superior for various reasons such as less postoperative febrile morbidity, less analgesia requirements, shorter operating time, less intra operative blood loss and adhesion formation, reduction in hospital stay and wound infection in the group undergoing Caesarean section by this technique. This study is to find whether better postoperative outcomes of the Joel-Cohen incision group can be justified by the explanations of fundamentals of the basic sciences. Literature was reviewed for randomized clinical trials and review articles comparing the different kinds of abdominal incisions for Caesarean section. The study revealed that the Joel-Cohen method was beneficial. The fundamentals of basic sciences were studied to try to find an explanation to the enumerated advantages of the Joel-Cohen procedure; attributing to the differences in the techniques used.


Subject(s)
Cesarean Section/adverse effects , Cesarean Section/methods , Abdominal Wall/anatomy & histology , Abdominal Wall/surgery , Blood Loss, Surgical , Female , Humans , Length of Stay , Pain, Postoperative/drug therapy , Pregnancy , Time Factors
16.
Curr Cancer Drug Targets ; 9(3): 298-306, 2009 May.
Article in English | MEDLINE | ID: mdl-19442050

ABSTRACT

Over the past two decades, a number of chemical entities have been investigated in the continuing quest to reverse P-glycoprotein (P-gp) mediated multidrug resistance (MDR) in cancer cells and some have undergone clinical trials, but currently none are in clinical use. Unfortunately, most of these agents suffer clinically from their intrinsic toxicity or from undesired effects on the pharmacokinetics of the accompanying anti-cancer drugs. An acridonecarboxamide (GF120918), Imidazo acridone (C(1311)) and timethylene acridone derivative 1,3-bis(9-oxoacridin-10-yl)-propane (PBA) have already been shown to be among the group of compounds known to modify P-gp mediated MDR in cancer. In the recent past it has been identified that various N(10)-substituted acridones can reverse the multidrug resistance (MDR) in cancer by selectively inhibiting the multidrug resistance associated protein (MRP) and calmodulin dependent cyclic AMP phosphodiesterase. This article envisages the various drugs being developed for treating MDR in cancer cells and especially the acridone derivatives which are being developed by the author.


Subject(s)
Antineoplastic Agents/therapeutic use , Drug Design , Drug Resistance, Multiple/physiology , Neoplasms/drug therapy , ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors , ATP Binding Cassette Transporter, Subfamily B, Member 1/drug effects , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP-Binding Cassette Transporters/classification , ATP-Binding Cassette Transporters/drug effects , ATP-Binding Cassette Transporters/metabolism , Acridones/pharmacology , Drug Resistance, Multiple/drug effects , Gene Expression Regulation, Neoplastic , Humans
17.
Chem Biol Interact ; 176(2-3): 212-9, 2008 Nov 25.
Article in English | MEDLINE | ID: mdl-18638463

ABSTRACT

We report herein in vitro anti-proliferative activity and duplex DNA complex studies of a series of N10-substituted acridone derivatives. All the molecules have been designed on the basis of the presence of specific recognition patterns consisting of hydrogen bond acceptors (or electron donors), carbonyl, chloro groups with precise spatial separation and structural features (lipophilicity, positive charge at neutral pH and presence of aromatic rings). The in vitro cytotoxic effects have been demonstrated against human promyelocytic leukemia sensitive cell line (HL-60), including its multidrug cross-resistance of two main (P-gp and MRP) phenotype sublines vincristine-resistant (HL-60/VINC) and doxorubicin-resistant (HL-60/DX) cancer cell lines. Compound 4 showed very good activity against sensitive and resistant cell lines. The noncovalent complexes of these molecules with DNA duplex has been investigated in gas phase by using a fast, robust and sensitive electrospray ionization mass spectrometry (ESI-MS) technique. Equilibrium association constants (K1) and percentage of intact complexes were determined. The combined results show that these acridone derivatives interact with DNA duplex by intercalation between the base pairs, possess higher affinity to GC than AT base pairs of the DNA and they could not interact noncovalently with the minor grooves of the DNA in solution-free gas phase. Examination of the relationship between lipophilicity and cytotoxic properties of acridone derivatives showed a poor correlation. The in vitro cytotoxic studies in resistant cancer cell lines of compound 4 showed that it might be a promising new hit for further development of anti-MDR agent.


Subject(s)
Acridones/chemistry , Acridones/toxicity , DNA/chemistry , DNA/drug effects , Drug Resistance, Multiple , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , HL-60 Cells , Humans , Molecular Structure , Molecular Weight , Spectrometry, Mass, Electrospray Ionization , Stereoisomerism , Structure-Activity Relationship
19.
Int J Gynecol Cancer ; 16(4): 1591-5, 2006.
Article in English | MEDLINE | ID: mdl-16884371

ABSTRACT

The aim of this study was to determine the prevalence of human papillomavirus (HPV) genotypes in tissue with cervical neoplasias in patients from south and east India. Cross-sectional cervical tissue was obtained from 100 patients from south India and 30 patients from east India who had a biopsy for clinically invasive cervical cancer or cervical intraepithelial neoplasia (CIN) in a tertiary care hospital in India. DNA amplification was done with biotinylated PGMY 09/11 primers, and the line blot assay was used to determine the HPV genotype. HPV DNA was detected in 95% of invasive cancers (113/119) and 91% of CINs (10/11). A single HPV type was found in 100 women (77%), and mixed infections were found in 23 women (18%). HPV 16 (60%) and HPV 18 (14%) were the most frequent types, but 16 other types (26, 31, 33, 35, 42, 45, 51, 52, 53, 56, 58, 61, 62, 64, 81, and 82) were also identified. HPV 16 was present in 63% of patients from south India and in 50% of patients from east India, while HPV 18 was present in 12% and 20%, respectively. There are several high-risk HPV types associated with cervical neoplasias of which types 16 and 18 are the most common.


Subject(s)
Human papillomavirus 16/genetics , Human papillomavirus 18/genetics , Papillomavirus Infections/virology , Uterine Cervical Neoplasms/virology , Adolescent , Adult , Carcinoma, Adenosquamous/epidemiology , Carcinoma, Adenosquamous/virology , Carcinoma, Neuroendocrine/epidemiology , Carcinoma, Neuroendocrine/virology , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/virology , DNA, Viral/genetics , Female , Genotype , Human papillomavirus 16/isolation & purification , Human papillomavirus 16/pathogenicity , Human papillomavirus 18/isolation & purification , Human papillomavirus 18/pathogenicity , Humans , India/epidemiology , Papillomavirus Infections/epidemiology , Polymerase Chain Reaction , Uterine Cervical Neoplasms/epidemiology , Uterine Cervical Dysplasia/epidemiology , Uterine Cervical Dysplasia/virology
20.
J Phys Condens Matter ; 18(17): 4135-42, 2006 May 03.
Article in English | MEDLINE | ID: mdl-21690769

ABSTRACT

The effect of swift heavy ion (SHI) irradiation on InGaAs/GaAs heterostructures is studied using Raman spectroscopy and atomic force microscopy (AFM). The structures consist of molecular beam epitaxy (MBE) grown InGaAs layers on GaAs(001), having layer thicknesses of 12, 36, 60 and 96 nm. After irradiation, the GaAs type longitudinal optical (LO) mode blue shifted to higher frequency in thin samples and red shifted towards lower frequency in thick samples. These results are discussed invoking the penetration depth of the probe radiation (λ = 514.5 nm) in InGaAs. Deconvoluting the Raman spectra of thin samples indicates a compressive strain developed in the substrate, close to the interface upon irradiation. This modification and diffusion of indium across the interface results in an increase of strain and reduction of the defect densities in the InGaAs layer. The variations in FWHM of the Raman modes are discussed in detail. The surface morphology of these heterostructures has been studied by AFM before and after SHI irradiation. These studies, combined with Raman results, help to identify different relaxation regimes.

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