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1.
Molecules ; 29(11)2024 May 22.
Article in English | MEDLINE | ID: mdl-38893314

ABSTRACT

The measurement of glucose concentration is a fundamental daily care for diabetes patients, and therefore, its detection with accuracy is of prime importance in the field of health care. In this study, the fabrication of an electrochemical sensor for glucose sensing was successfully designed. The electrode material was fabricated using polyaniline and systematically characterized using scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and UV-visible spectroscopy. The polyaniline nanofiber-modified electrode showed excellent detection ability for glucose with a linear range of 10 µM to 1 mM and a detection limit of 10.6 µM. The stability of the same electrode was tested for 7 days. The electrode shows high sensitivity for glucose detection in the presence of interferences. The polyaniline-modified electrode does not affect the presence of interferences and has a low detection limit. It is also cost-effective and does not require complex sample preparation steps. This makes it a potential tool for glucose detection in pharmacy and medical diagnostics.


Subject(s)
Aniline Compounds , Biosensing Techniques , Electrochemical Techniques , Electrodes , Glucose , Nanofibers , Aniline Compounds/chemistry , Nanofibers/chemistry , Electrochemical Techniques/methods , Glucose/analysis , Glucose/chemistry , Biosensing Techniques/methods , Limit of Detection , Humans , Spectroscopy, Fourier Transform Infrared
2.
Emerg Infect Dis ; 29(10): 2032-2043, 2023 10.
Article in English | MEDLINE | ID: mdl-37735741

ABSTRACT

To examine protective and risk factors for Buruli ulcer (BU), we conducted a case-control study of 245 adult BU cases and 481 postcode-matched controls across BU-endemic areas of Victoria, Australia. We calculated age- and sex-adjusted odds ratios for socio-environmental, host, and behavioral factors associated with BU by using conditional logistic regression. Odds of BU were >2-fold for persons with diabetes mellitus and persons working outdoors who had soil contact in BU-endemic areas (compared with indoor work) but were lower among persons who had bacillus Calmette-Guérin vaccinations. BU was associated with increasing numbers of possums and with ponds and bore water use at residences. Using insect repellent, covering arms and legs outdoors, and immediately washing wounds were protective; undertaking multiple protective behaviors was associated with the lowest odds of BU. Skin hygiene/protection behaviors and previous bacillus Calmette-Guérin vaccination might provide protection against BU in BU-endemic areas.


Subject(s)
BCG Vaccine , Buruli Ulcer , Adult , Humans , Buruli Ulcer/epidemiology , Buruli Ulcer/prevention & control , Case-Control Studies , Risk Factors , Victoria/epidemiology
3.
Adv Funct Mater ; 31(22)2021 May 26.
Article in English | MEDLINE | ID: mdl-36213489

ABSTRACT

Advanced wound scaffolds that integrate active substances to treat chronic wounds have gained significant recent attention. While wound scaffolds and advanced functionalities have previously been incorporated into one medical device, the wirelessly triggered release of active substances has remained the focus of many research endeavors. To combine multiple functions including light-triggered activation, anti-septic, angiogenic, and moisturizing properties, we have developed a 3D printed hydrogel patch encapsulating vascular endothelial growth factor (VEGF) decorated with photoactive and antibacterial tetrapodal zinc oxide (t-ZnO) microparticles. To achieve the smart release of VEGF, t-ZnO was modified by chemical treatment and activated through UV/visible light exposure. This process would also make the surface rough and improve protein adhesion. The elastic modulus and degradation behavior of the composite hydrogels, which must match the wound healing process, were adjusted by changing t-ZnO concentrations. The t-ZnO-laden composite hydrogels can be printed with any desired micropattern to potentially create a modular elution of various growth factors. The VEGF decorated t-ZnO-laden hydrogel patches showed low cytotoxicity and improved angiogenic properties while maintaining antibacterial functions in vitro. In vivo tests showed promising results for the printed wound patches, with less immunogenicity and enhanced wound healing.

4.
Mult Scler ; 27(13): 2093-2102, 2021 11.
Article in English | MEDLINE | ID: mdl-33591218

ABSTRACT

BACKGROUND: While employment rates have increased in people with multiple sclerosis (PwMS), little is known about the longitudinal trends of work productivity. OBJECTIVE: To describe the longitudinal patterns of work productivity and examine the factors associated with annual change of work productivity of PwMS. METHODS: Study participants were employed participants of the Australian MS Longitudinal Study (AMSLS) followed from 2015 to 2019 with at least two repeated measures (n = 2121). We used linear mixed models to examine if the within-individual variations in MS symptoms are associated with changes in work productivity. RESULTS: The mean annual change in work productivity between 2015 and 2019 was -0.23% (SD = 18.68%). Not the actual severity of symptoms but rather the changes in severity of symptoms that are associated with change in work productivity in the same year. In a multivariable model, every unit increase in mean annual change in 'pain and sensory symptoms', 'feelings of anxiety and depression', and 'fatigue and cognitive symptoms' were independently associated with 2.43%, 1.55% and 1.01% annual reductions in work productivity, respectively. CONCLUSION: Individual changes in work productivity are largely driven by the changes in symptom severity rather than the absolute severity. Stabilising/improving MS symptoms might improve work productivity.


Subject(s)
Multiple Sclerosis , Absenteeism , Australia , Efficiency , Humans , Longitudinal Studies
5.
J Trop Pediatr ; 60(3): 238-44, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24519674

ABSTRACT

Neonatal care practices have been shown to vary across tribal communities. This cross-sectional study was conducted in tribal block in Nabarangpur district of Odisha, India, to measure perinatal and antenatal practices by qualitative inquiries of 55 mothers who had babies aged <60 days and from 11 traditional birth attendants. Reasons for home deliveries were cited as easy availability of traditional birth attendants and family preferences. Application of indigenously made substances on umbilical stump and skin of the baby, bathing baby immediately after birth, late initiation of breast-feeding and 'Budu practices' were common. Cultural issues, decision of family members and traditional beliefs still play a crucial role in shaping neonatal care practice in tribal communities. Awareness on child care, ethnographic understanding of health-seeking behavior of tribal community and mobilization of community by health workers can be useful in improving health status of mothers and newborn babies in tribal population.


Subject(s)
Home Childbirth , Infant Care/methods , Midwifery , Perinatal Care/methods , Prenatal Care/methods , Adult , Anthropology, Cultural , Breast Feeding/statistics & numerical data , Cross-Sectional Studies , Culture , Delivery, Obstetric/methods , Female , Health Knowledge, Attitudes, Practice , Health Services Accessibility , Home Childbirth/statistics & numerical data , Humans , India , Infant , Infant Care/statistics & numerical data , Infant Mortality , Infant, Newborn , Interviews as Topic , Patient Acceptance of Health Care , Pregnancy , Qualitative Research
6.
Int J Infect Dis ; 145: 107078, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38697606

ABSTRACT

OBJECTIVES: Estimates of secondary infections are variedly reported, with few studies done in Australia. We investigated the occurrence and impact of secondary infections complicating COVID-19 and post-COVID-19 admissions in Victoria, Australia, 2020-2023. METHODS: We used linked population-wide data sets and specific International Classification of Disease, 10th Revision codes to identify and estimate the occurrence of secondary infections. Using hospital/intensive care unit length of stay in negative binomial regression and mortality, we examined the impact of secondary infections. RESULTS: Secondary infections were identified in 6.9% (13,467 of 194,660) of COVID-19 and post-COVID-19 admissions: 6.0% (11,651 of 194,660) bacterial, 0.9% (1691 of 194,660) viral, and 0.2% (385 of 194,660) fungal. Prevalence was highest during the pre-Delta (10.4%) and Omicron-BA2 (8.1%) periods. Sepsis and pneumonia were the most reported syndromes; the occurrence of sepsis declined gradually over time. The odds of secondary infections were higher among the ≥70-year-olds (adjusted odds ratio (aOR) 3.76, 95% confidence interval [CI] 3.43-4.14, vs 20-29-year-olds), individuals with chronic conditions (aOR 3.15, 95% CI 2.88-3.45, vs those without), the unvaccinated (aOR 1.59, 95% CI 1.45-1.75), and the lowest socioeconomic group (aOR 1.12, 95% CI 1.05-1.19). Patients with secondary infections had 2.43 times longer hospital length of stay and 9.60 times longer intensive care unit length of stay than those without secondary infections. The mortality risk was 2.17 times higher in those with secondary infections. CONCLUSIONS: Secondary infections occurred in 69 per 1000 COVID-19-associated hospital admissions in Victoria, mostly in high-risk groups, and were associated with severe outcomes.


Subject(s)
COVID-19 , Hospitalization , SARS-CoV-2 , Humans , COVID-19/epidemiology , COVID-19/mortality , Victoria/epidemiology , Female , Male , Risk Factors , Aged , Middle Aged , Prevalence , Adult , Hospitalization/statistics & numerical data , Young Adult , Adolescent , Length of Stay/statistics & numerical data , Aged, 80 and over , Coinfection/epidemiology , Child, Preschool , Infant , Child , Intensive Care Units/statistics & numerical data , Sepsis/epidemiology , Sepsis/mortality , Bacterial Infections/epidemiology , Bacterial Infections/mortality , Mycoses/epidemiology , Infant, Newborn
7.
Malar J ; 12: 351, 2013 Oct 02.
Article in English | MEDLINE | ID: mdl-24088525

ABSTRACT

BACKGROUND: Early diagnosis and prompt treatment is a cornerstone of malaria control. In India, artemisinin combination therapy (ACT) became the first-line treatment for falciparum malaria and rapid diagnostic test (RDTs) kits were recommended for use at the grass-root level in the new malaria treatment policy (2010). Odisha State contributes about one-fourth of the total Indian malaria burden and 40% of falciparum infection. The present study assessed the health system readiness to deploy RDTs and ACT for malaria control across the State. METHODS: Data collection was carried out from February to July 2012. Five of Odisha's 30 districts were selected through stratified random sampling, with stratification based on the phased roll-out of ACT and RDT. Two administrative 'blocks' were selected randomly in each district and data collected through health facility, auxiliary nurse midwives (ANMs) and accredited social health activist (ASHAs) assessments. Key informant interviews were conducted with individuals involved in the implementation of the malaria control programme. RESULTS: Of the 220 ANMs interviewed, 51.4% had been trained in malaria case management, including the use of ACT and RDT. A high proportion of ANM (80%) and AHSA (77%) had the necessary level of knowledge to be able to use RDT for malaria diagnosis. The proportion of ASHAs trained on malaria case management was 88.9% (209/235). However, 71% of ANM and 55% of ASHAs usually referred falciparum-positive patients to the health facility for treatment, the major reason for referral being the non-availability of drugs at the ANM and ASHA level. CONCLUSION: The relatively high level of knowledge about how to diagnose and treat malaria at the grass-root level was undermined by the poor availability of RDTs, ACT and primaquine tablets. This was associated with an unnecessarily high referral rate and potential delays in the treatment of this potentially life-threatening infection. Improvements in the supply chain for RDTs and ACT could dramatically enhance the effectiveness of malaria control in Odisha.


Subject(s)
Health Services Research , Malaria/diagnosis , Malaria/drug therapy , Public Health Administration/methods , Adult , Antimalarials/supply & distribution , Artemisinins/supply & distribution , Cross-Sectional Studies , Diagnostic Tests, Routine/statistics & numerical data , Humans , India , Interviews as Topic , Lactones/supply & distribution , Malaria/prevention & control , Middle Aged , Primaquine/supply & distribution , Young Adult
8.
Materials (Basel) ; 16(7)2023 Mar 30.
Article in English | MEDLINE | ID: mdl-37049064

ABSTRACT

We report the synthesis of Fe3O4/graphene (Fe3O4/Gr) nanocomposite for highly selective and highly sensitive peroxide sensor application. The nanocomposites were produced by a modified co-precipitation method. Further, structural, chemical, and morphological characterization of the Fe3O4/Gr was investigated by standard characterization techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and high-resolution TEM (HRTEM), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS). The average crystal size of Fe3O4 nanoparticles was calculated as 14.5 nm. Moreover, nanocomposite (Fe3O4/Gr) was employed to fabricate the flexible electrode using polymeric carbon fiber cloth or carbon cloth (pCFC or CC) as support. The electrochemical performance of as-fabricated Fe3O4/Gr/CC was evaluated toward H2O2 with excellent electrocatalytic activity. It was found that Fe3O4/Gr/CC-based electrodes show a good linear range, high sensitivity, and a low detection limit for H2O2 detection. The linear range for the optimized sensor was found to be in the range of 10-110 µM and limit of detection was calculated as 4.79 µM with a sensitivity of 0.037 µA µM-1 cm-2. The cost-effective materials used in this work as compared to noble metals provide satisfactory results. As well as showing high stability, the proposed biosensor is also highly reproducible.

9.
Acta Biomater ; 139: 141-156, 2022 02.
Article in English | MEDLINE | ID: mdl-34818579

ABSTRACT

Myocardial infarction (MI) represents one of the most prevalent cardiovascular diseases, with a highly relevant and impactful role in public health. Despite the therapeutic advances of the last decades, MI still begets extensive death rates around the world. The pathophysiology of the disease correlates with cardiomyocyte necrosis, caused by an imbalance in the demand of oxygen to cardiac tissues, resulting from obstruction of the coronary flow. To alleviate the severe effects of MI, the use of various biomaterials exhibit vast potential in cardiac repair and regeneration, acting as native extracellular matrices. These hydrogels have been combined with nano sized or functional materials which possess unique electrical, mechanical, and topographical properties that play important roles in regulating phenotypes and the contractile function of cardiomyocytes even in adverse microenvironments. These nano-biomaterials' differential properties have led to substantial healing on in vivo cardiac injury models by promoting fibrotic scar reduction, hemodynamic function preservation, and benign cardiac remodeling. In this review, we discuss the interplay of the unique physical properties of electrically conductive nano-biomaterials, are able to manipulate the phenotypes and the electrophysiological behavior of cardiomyocytes in vitro, and can enhance heart regeneration in vivo. Consequently, the understanding of the decisive roles of the nano-biomaterials discussed in this review could be useful for designing novel nano-biomaterials in future research for cardiac tissue engineering and regeneration. STATEMENT OF SIGNIFICANCE: This study introduced and deciphered the understanding of the role of multimodal cues in recent advances of electrically conductive nano-biomaterials on cardiac tissue engineering. Compared with other review papers, which mainly describe these studies based on various types of electrically conductive nano-biomaterials, in this review paper we mainly discussed the interplay of the unique physical properties (electrical conductivity, mechanical properties, and topography) of electrically conductive nano-biomaterials, which would allow them to manipulate phenotypes and the electrophysiological behavior of cardiomyocytes in vitro and to enhance heart regeneration in vivo. Consequently, understanding the decisive roles of the nano-biomaterials discussed in the review could help design novel nano-biomaterials in future research for cardiac tissue engineering and regeneration.


Subject(s)
Biocompatible Materials , Myocytes, Cardiac , Biocompatible Materials/pharmacology , Biocompatible Materials/therapeutic use , Electric Conductivity , Myocytes, Cardiac/physiology , Regeneration , Tissue Engineering/methods
10.
Mult Scler Relat Disord ; 59: 103562, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35149393

ABSTRACT

INTRODUCTION: The global spread of COVID-19 has raised concerns about its possible impact on mental health. People living with multiple sclerosis (PwMS) are considered potentially vulnerable to the mental health effects of the pandemic, as they may be subject to increased social isolation. AIM: To systematically review the current evidence on the impact of the COVID-19 pandemic on mental health outcomes among PwMS. METHOD: We searched four major databases (Medline, EMBASE, PsychInfo and Scopus) and the WHO Global Health COVID-19 research database. We included peer-reviewed primary research studies using validated health-related quality of life (HRQOL) and psychometric screening tools to evaluate mental health outcomes among PwMS during the COVID-19 pandemic. Studies reporting data on the prevalence of mental health disorders, severity of psychological symptoms and contributing demographic and clinical factors for PwMS during the COVID-19 pandemic were included. RESULTS: Our initial search yielded 268 records; 19 studies (13 cross-sectional, 6 longitudinal) were included. Most were conducted during a peak in the pandemic in the host country via an online platform. The main mental health outcomes were depression, anxiety, stress, sleep quality and HRQOL. The included studies used a variety of outcome assessment tools and study designs. The prevalence of mental health issues such as depression, anxiety and stress were high among PwMS during the pandemic. In addition, compared to control populations, PwMS experienced more severe symptoms of depression and stress during the COVID-19 outbreak. However, results from longitudinal studies demonstrate that the severity of mental health symptoms among PwMS during the pandemic were not significantly different compared with the pre-pandemic period. CONCLUSION: Although mental health issues such as anxiety and depression were common among PwMS during the pandemic, current evidence suggests that mental health among PwMS has not been significantly affected by pandemic-related restrictive measures. Instead, the observed differences may be the result of pre-pandemic differences in prevalence and severity. Where possible, future studies should seek to address the methodological issues identified in the included studies to ensure that data collected during the pandemic can be synthesized into recommendations for policy and practice.


Subject(s)
COVID-19 , Multiple Sclerosis , Anxiety/epidemiology , COVID-19/epidemiology , Cross-Sectional Studies , Depression/epidemiology , Humans , Multiple Sclerosis/complications , Multiple Sclerosis/epidemiology , Pandemics , Quality of Life , SARS-CoV-2 , Stress, Psychological/epidemiology
11.
Bioinorg Chem Appl ; 2022: 6482133, 2022.
Article in English | MEDLINE | ID: mdl-36276988

ABSTRACT

In the present study, a highly selective and sensitive electrochemical sensing platform for the detection of dopamine was developed with CuO nanoparticles embedded in N-doped carbon nanostructure (CuO@NDC). The successfully fabricated nanostructures were characterized by standard instrumentation techniques. The fabricated CuO@NDC nanostructures were used for the development of dopamine electrochemical sensor. The reaction mechanism of a dopamine on the electrode surface is a three-electron three-proton process. The proposed sensor's performance was shown to be superior to several recently reported investigations. Under optimized conditions, the linear equation for detecting dopamine by differential pulse voltammetry is I pa (µA) = 0.07701 c (µM) - 0.1232 (R 2 = 0.996), and the linear range is 5-75 µM. The limit of detection (LOD) and sensitivity were calculated as 0.868 µM and 421.1 µA/µM, respectively. The sensor has simple preparation, low cost, high sensitivity, good stability, and good reproducibility.

12.
Mult Scler Relat Disord ; 54: 103131, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34274739

ABSTRACT

BACKGROUND: Studies have documented reduced work capacity and work productivity loss in multiple sclerosis (MS). Little is known about the longitudinal trajectories of work productivity in MS. OBJECTIVES: To examine trajectories of work productivity in people living with multiple sclerosis (PwMS) and the factors associated with the trajectories. METHODS: Study participants were employed participants of the Australian MS Longitudinal Study (AMSLS) followed from 2015 to 2019 with at least two repeated measures (n=2121). We used group-based trajectory modelling to identify unique work productivity trajectories in PwMS. RESULTS: We identified three distinct trajectories of work productivity: 'moderately reduced' (17.0% of participants) with a mean work productivity level of 47.6% in 2015 (slope -0.97% per year (p= 0.22)), 'mildly reduced' (46.7%) with a mean work productivity of 86.3% in 2015 (slope 0.70% per year (p=0.12)), and 'full' (36.3%) with a mean work productivity of 99.7% in 2015 (slope 0.29% per year (p= 0.30)). Higher education level, higher disability, and higher MS symptom severity are associated with increased probability of being in a worse work productivity trajectory. CONCLUSION: We identified three distinct work productivity trajectories in PwMS which were stable over time and differentiated by their baseline level of work productivity.


Subject(s)
Multiple Sclerosis , Absenteeism , Australia/epidemiology , Efficiency , Humans , Longitudinal Studies , Multiple Sclerosis/epidemiology
13.
Micron ; 39(7): 1008-19, 2008 Oct.
Article in English | MEDLINE | ID: mdl-17977735

ABSTRACT

We describe the use of atomic force microscopy (AFM) to investigate the nanomechanical properties of annulus fibrosus (AF)-the outer fibrous layer of an intervertebral disc (IVD) encapsulating the inner jelly-like mass known as the nucleus pulposus (NP). Disk disease, degenerated discs, slipped discs, and herniated discs are common terms often linked to back pain and are caused due to degeneration of IVD. Due to the variations in the structure and biochemical composition of the IVD, studies of macromechanical properties in the motion segment or AF may lack all significant nanomechanical responses or behaviors. Existing studies do not report the micro or nano level of mechanics of IVD components and whether the nanomechanics of this tissue mimic its macromechanical behavior is not known. Our studies used AFM to investigate the regional micromechanical properties of the AF that have been otherwise difficult due to small sample size of the tissue. Five different zones including peripheral and central were tested mechanically as well as biochemically. Qualitative biochemical staining and quantitative values of nanomechanical properties of different zones are compared and discussed in detail. The results of nanomechanical investigations described in this study not only reveal its mimic at macroscopic level, they represent an important step towards establishing a framework for testing and comparing tissue engineered IVD replacements with native tissues.


Subject(s)
Intervertebral Disc/physiology , Mechanical Phenomena/physiology , Microscopy, Atomic Force/methods , Rabbits/anatomy & histology , Animals , Biomechanical Phenomena , Intervertebral Disc/cytology , Microscopy, Atomic Force/instrumentation
14.
Methodist Debakey Cardiovasc J ; 13(3): 98-105, 2017.
Article in English | MEDLINE | ID: mdl-29743993
15.
J Appl Physiol (1985) ; 98(5): 1922-9, 2005 May.
Article in English | MEDLINE | ID: mdl-15640386

ABSTRACT

Titanium implants commonly used in orthopedics and dentistry integrate into host bone by a complex and coordinated process. Despite increasingly well illustrated molecular healing processes, mechanical modulation of implant bone ingrowth is poorly understood. The objective of the present study was to determine whether micromechanical forces applied axially to titanium implants modulate bone ingrowth surrounding intraosseous titanium implants. We hypothesized that small doses of micromechanical forces delivered daily to the bone-implant interface enhance implant bone ingrowth. Small titanium implants were placed transcortically in the lateral aspect of the proximal femur in 15 New Zealand White rabbits under general anesthesia and allowed to integrate with the surrounding bone for 6 wk. Micromechanical forces at 200 mN and 1 Hz were delivered axially to the right femur implants for 10 min/day over 12 consecutive days, whereas the left femur implants served as controls. The average bone volume 1 mm from mechanically loaded implants (n = 15) was 73 +/- 12%, which was significantly greater than the average bone volume (52 +/- 21%) of the contralateral controls (n = 15) (P < 0.01). The average number of osteoblast-like cells per endocortical bone surface was 55 +/- 8 cells/mm(2) for mechanically loaded implants, which was significantly greater than the contralateral controls (35 +/- 6 cells/mm(2)) (P < 0.01). Dynamic histomorphometry showed a significant increase in mineral apposition rate and bone-formation rate of mechanically stressed implants (3.8 +/- 1.2 microm/day and 2.4 +/- 1.0 microm(3).microm(-2).day(-1), respectively) than contralateral controls (2.2 +/- 0.92 microm/day and 1.2 +/- 0.60 microm(3).microm(-2).day(-1), respectively; P < 0.01). Collectively, these data suggest that micromechanical forces delivered axially on intraosseous titanium implants may have anabolic effects on implant bone ingrowth.


Subject(s)
Biomechanical Phenomena/methods , Bone Nails , Femur/growth & development , Titanium , Animals , Male , Prostheses and Implants , Rabbits , Weight-Bearing/physiology
16.
Micron ; 35(7): 565-73, 2004.
Article in English | MEDLINE | ID: mdl-15219903

ABSTRACT

The platelet membrane receptor alpha(IIb) beta(3) binds to adsorbed protein ligands including fibrinogen, von Willebrand factor and fibronectin, and is critically important in mediating platelet adhesion to damaged subendothelium and to synthetic biomaterial surfaces. This receptor is a member of the integrin family, a highly prevalent class of heterodimeric molecules consisting of a single alpha and beta subunit. In an ongoing effort to understand the mechanisms underlying platelet adhesion events, high-resolution atomic force microscopy (AFM) under dynamic conditions was used to obtain images of alpha(IIb) beta(3) molecules as well as aggregates of the protein. Images of integrin molecules were obtained by tapping mode AFM under aqueous buffer conditions following adsorption on a series of ultrasmooth model surfaces. On a model hydrophobic surface, detergents stabilizing the protein in solution competed for surface adsorption sites. When this detergent was removed from the system, the protein was predominantly seen as aggregates with head groups pointing outward. A limited number of individual integrin molecules were observed, and were found to have dimensions consistent with those reported previously by electron microscopy studies. Integrin molecules showed weak adhesion to the two hydrophilic surfaces used in the study, although formation of a lipid bilayer around surface-adsorbed molecules improved the resolution. At longer time periods, the integrin molecules embedded in this lipid bilayer exhibited sufficient mobility to form molecular aggregates. The structural measurements described in this study not only reveal three-dimensional features of the molecule, they represent an important step towards dynamic adsorption experiments and visualizing the integrin interacting with surface-adsorbed proteins as in biomaterial-induced thrombogenesis.


Subject(s)
Blood Platelets/metabolism , Microscopy, Atomic Force/methods , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Adsorption , Biocompatible Materials , Humans , Hydrophobic and Hydrophilic Interactions , Materials Testing , Microscopy, Atomic Force/instrumentation , Surface Properties
17.
Infect Dis Poverty ; 3: 31, 2014.
Article in English | MEDLINE | ID: mdl-25237478

ABSTRACT

BACKGROUND: Lymphatic filariasis is targeted for elimination in India through mass drug administration (MDA) with diethylcarbamazine (DEC) combined with albendazole (ABZ). For the strategy to be effective, >65% of those living in endemic areas must be covered by and compliant to MDA. Post the MDA 2011 campaign in the endemic district of Odisha, we conducted a survey to assess: (i) the filariasis knowledge in the community, (ii) the coverage and compliance of MDA from the community perspective, and (iii) factors affecting compliance, as well as the operational issues involved in carrying out MDA activities from the drug distributor's perspective. METHODS: A sample of 691 participants - both male and female, aged two years or above - were selected through multistage stratified sampling and interviewed using a semi-structured questionnaire. Additionally, drug distributors and the medical officers in charge of the MDA were also interviewed to understand some of the operational issues encountered during MDA. RESULTS: Ninety-nine percent of the study participants received DEC and ABZ tablets during MDA, of which only just above a quarter actually consumed the drugs. The cause of non-compliance was mostly due to fear of side effects, lack of awareness of the benefits of MDA, and non-attendance of health staff in the villages. Lack of adequate training of drug distributors and poor health communication activities before the MDA campaign commenced and the absence of follow-up by health workers following MDA were a few of the operational difficulties encountered during the MDA campaign. CONCLUSION: Currently MDA is restricted to the distribution of drugs only and the key issues of implementation in compliance, health education, managing side effects, and logistics are not given enough attention. It is therefore essential to address the issues linked to low compliance to make the program more efficient and achieve the goal of filariasis elimination.

18.
HeartRhythm Case Rep ; 4(1): 34-35, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29379725
19.
ASAIO J ; 53(2): 219-28, 2007.
Article in English | MEDLINE | ID: mdl-17413564

ABSTRACT

Mesenchymal stem cells (MSCs) are progenitors for tissues such as bone and cartilage. In this report, the actin cytoskeleton and nanomechanobiology of human mesenchymal stem cells (hMSCs) were studied using fluorescence microscopy and atomic force microscopy (AFM). Human MSCs were differentiated into chondrocytes and osteoblasts as per previous approaches. Cytochalasin D (CytD) was used to temporarily disrupt cytoskeleton in hMSCs, hMSC-chondrocytes (hMSC-Cys) and hMSC-osteoblasts (hMSC-Obs). Fluorescence microscopy revealed a dose-dependent response to CytD. Removal of CytD from the media of cytoskeleton-disrupted cells led to the recovery of the cytoskeletal structures, as confirmed by both fluorescence microscopy and AFM. Force-volume imaging by AFM evaluated the nanomechanics of all three cell types before, during, and after CytD treatment. Cytochalasin D disruption of cytoskeleton had marked effects on hMSCs and hMSC-Cys, in comparison with limited cytoskeleton disruption in hMSC-Obs, as confirmed qualitatively by fluorescence microscopy and quantitatively by AFM. Treatment with CytD resulted in morphology changes of all cell types, with significant decreases in the observed Young's Moduli of hMSCs and hMSC-Cys. These data suggest human mesenchymal stem cells alter their cytoskeletal components during differentiation. Additional studies will address the mechanisms of cytoskeletal changes using biochemical and biophysical methods.


Subject(s)
Actins/metabolism , Chondrocytes/physiology , Cytoskeleton/metabolism , Mesenchymal Stem Cells/cytology , Osteoblasts/physiology , Actins/drug effects , Actins/ultrastructure , Biomechanical Phenomena , Cell Differentiation , Cell Survival/drug effects , Cells, Cultured , Chondrocytes/drug effects , Chondrocytes/ultrastructure , Cytochalasin D/pharmacology , Cytoskeleton/drug effects , Cytoskeleton/ultrastructure , Dose-Response Relationship, Drug , Fluorescent Dyes , Humans , Microscopy, Atomic Force , Microscopy, Fluorescence , Nucleic Acid Synthesis Inhibitors/pharmacology , Osteoblasts/drug effects , Osteoblasts/ultrastructure , Phalloidine/metabolism , Rhodamines , Time Factors
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