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1.
Cureus ; 16(3): e56206, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38618476

RESUMEN

Background Social media is widely used in the medical field, and people often utilize it to learn about their symptoms prior to consulting with a healthcare professional. Hence, the study aims to investigate the influence of social media on self-perceived oral health practices among patients. Methodology A cross-sectional study design was adopted, with a questionnaire comprising 15 closed-ended questions. The sample size was estimated to be 451 participants based on the findings from the pilot study. The face validity of the questionnaire was assessed by a subject matter expert (0.83%), and the reliability was measured using Kappa statistics (0.86). The percentile was determined to assess the overall self-perceived oral health practices of the participants. The data was analyzed using descriptive analysis, chi-square test, and multivariate regression analysis at statistical significance (p ≤ 0.05). Results The majority of participants belonged to urban areas (66.5%), with an average age of 38.19 ± 6.70. The participants in urban 184 (61.3%) and rural 102 (67.5%) believed that social media provided better knowledge regarding oral health, which was statistically significant (p = 0.046). The majority of the participants, 267 (59.2%), spent more than 30 minutes to three hours per day on social media. It was found that participants who possessed professional occupations had increased odds of having good oral health practices on social media (p = 0.043). Conclusion The participants believed that social media provided better knowledge regarding oral health, and self-perceived practices among the participants were found to be poor. Social media platforms provide new educational possibilities in the dentistry sector, but their potential is neglected and unappreciated.

2.
ACS Appl Mater Interfaces ; 16(9): 11159-11171, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38385360

RESUMEN

For the improved delivery of cancer therapeutics and imaging agents, the conjugation of cell-penetrating peptides (CPPs) increases the cellular uptake and water solubility of agents. Among the various CPPs, arginine-rich peptides have been the most widely used. Combining CPPs with enzyme-responsive peptides presents an innovative strategy to target specific intracellular enzymes in cancer cells and when combined with the appropriate click chemistry can enhance theranostic drug delivery through the formation of intracellular self-assembled nanostructures. However, one drawback of CPPs is their high positive charge which can cause nonspecific binding, leading to off-target accumulation and potential toxicity. Hence, balancing cell-specific penetration, toxicity, and biocompatibility is essential for future clinical efficacy. We synthesized six cancer-specific, legumain-responsive RnAANCK peptides containing one to six arginine residues, with legumain being an asparaginyl endopeptidase that is overexpressed in aggressive prostate tumors. When conjugated to Alexa Fluor 488, R1-R6AANCK peptides exhibited a concentration- and time-dependent cell penetration in prostate cancer cells, which was higher for peptides with higher R values, reaching a plateau after approximately 120 min. Highly aggressive DU145 prostate tumor cells, but not less aggressive LNCaP cells, self-assembled nanoparticles in the cytosol after the cleavage of the legumain-specific peptide. The in vivo biocompatibility was assessed in mice after the intravenous injection of R1-R6AANCK peptides, with concentrations ranging from 0.0125 to 0.4 mmol/kg. The higher arginine content in R4-6 peptides showed blood and urine indicators for the impairment of bone marrow, liver, and kidney function in a dose-dependent manner, with instant hemolysis and morbidity in extreme cases. These findings underscore the importance of designing peptides with the optimal arginine residue length for a proper balance of cell-specific penetration, toxicity, and in vivo biocompatibility.


Asunto(s)
Péptidos de Penetración Celular , Neoplasias , Animales , Ratones , Arginina/química , Péptidos de Penetración Celular/química , Neoplasias/tratamiento farmacológico
3.
Nanomaterials (Basel) ; 13(24)2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38132988

RESUMEN

In this paper we report an acid-modulated strategy for novel peptide microarray production on biosensor interfaces. We initially selected a controlled pore glass (CPG) as a support for solid-phase peptide synthesis (SPPS) to implement a chemistry that can be performed at the interface of multiple field effect transistor (FET) sensors, eventually to generate label-free peptide microarrays for protein screening. Our chemistry uses a temporary protection of the N-terminal amino function of each amino acid building block with a tert-butyloxycarbonyl (Boc) group that can be removed after each SPPS cycle, in combination with semi-permanent protection of the side chains of trifunctional amino acid residues. Such a protection scheme with a well-proven record of application in conventional, batchwise SPPS has been fine-tuned for optimal performance on CPG and, from there, translated to SPR chips that allow layer-by-layer monitoring of amino acid coupling. Our results validate this acid-modulated synthesis as a feasible approach for producing peptides in high yields and purity on flat glass surfaces, such as those in bio-FETs.

4.
Expert Rev Med Devices ; 20(12): 1251-1256, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753857

RESUMEN

BACKGROUND: The telemedicine/telehealth is well established and rapidly evolving innovation in modern practice of medicine. It is used in nearly every aspect of obstetrics and gynecology. Telehealth intervention may reduce the need for in-person visits amongst high-risk obstetric patients. It is an effective innovation for chronic gynecological conditions. RESEARCH DESIGN AND METHODS: This was a prospective, observational study where the online platform 'e-Sanjeevani' was used. It was a health care worker to doctor (specialist) consultation regarding the patient. After an interaction, provisional diagnosis and management plan was made, and an electronic prescription for the same was generated and printed at the patient's end. RESULTS: A total of 3219 patients were attended in 10 months. The majority of the cases had a gynecological problem (71.5%), with menstrual irregularity being the commonest. Among pregnant patients, consultations for early pregnancy complications were made in 29% of the cases. 5.8% were referred because of some surgical intervention. CONCLUSION: Non-emergency patients who can be managed medically can be prevented from unnecessary visits to the hospital and managed through teleconsultation, which decreases the burden of patient load at the tertiary center.


Asunto(s)
Ginecología , Obstetricia , Telemedicina , Femenino , Embarazo , Humanos , Centros de Atención Terciaria , Estudios Prospectivos
5.
Adv Sci (Weinh) ; 10(34): e2304164, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37715297

RESUMEN

Inspired by the principle of in situ self-assembly, the development of enzyme-activated molecular nanoprobes can have a profound impact on targeted tumor detection. However, despite their intrinsic promise, obtaining an optical readout of enzyme activity with high specificity in native milieu has proven to be challenging. Here, a fundamentally new class of Raman-active self-assembling bioorthogonal enzyme recognition (nanoSABER) probes for targeted tumor imaging is reported. This class of Raman probes presents narrow spectral bands reflecting their vibrational fingerprints and offers an attractive solution for optical imaging at different bio-organization levels. The optical beacon harnesses an enzyme-responsive peptide sequence, unique tumor-penetrating properties, and vibrational tags with stretching frequencies in the cell-silent Raman window. The design of nanoSABER is tailored and engineered to transform into a supramolecular structure exhibiting distinct vibrational signatures in presence of target enzyme, creating a direct causality between enzyme activity and Raman signal. Through the integration of substrate-specific for tumor-associated enzyme legumain, unique capabilities of nanoSABER for imaging enzyme activity at molecular, cellular, and tissue levels in combination with machine learning models are shown. These results demonstrate that the nanoSABER probe may serve as a versatile platform for Raman-based recognition of tumor aggressiveness, drug accumulation, and therapeutic response.


Asunto(s)
Neoplasias , Humanos , Neoplasias/diagnóstico por imagen , Imagen Óptica
6.
J Health Popul Nutr ; 42(1): 58, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37370167

RESUMEN

PURPOSE: Cancer is a leading cause of death in the Caribbean, and the Republic of Trinidad and Tobago is no exception. Evidence suggests that cancer incidence and mortality may vary based on demographic factors across the different cancer types. This study aimed to investigate the incidence and mortality trends associated with cancer cases in Trinidad and Tobago for the period 2008-2018, across different age groups, gender, and ethnicity. METHODS: Data on 15,029 incident cancer cases were reported to the Dr. Elizabeth Quamina Cancer Registry between 2008 and 2018. The retrospective data were analyzed by sex, ancestry, and age, and were reported using Trinidad and Tobago population statistics for the period 2008-2018. RESULTS: The incidence of prostate and breast cancers was high among males and females, respectively. Among males, the highest cancer mortality was associated with prostate, lung, colon, blood, and pancreatic cancers, respectively. Among females, the highest cancer mortality was associated with breast, ovary, colon, blood, and pancreatic cancers. The frequency of occurrence of the top five cancer sites was the highest among Afro-Trinidadians followed by Indo-Trinidadians. Most females diagnosed with breast cancer were at a localized stage, while most males diagnosed with breast cancer were at a distant or regional stage. Most individuals diagnosed with blood cancer were at a distant stage. For lung and colon cancer, the stage of diagnosis for most males and females was either distant or unknown. Majority of males are diagnosed with prostate cancer at an unknown stage. CONCLUSIONS: The findings indicate highest cancer incidence and mortality occur among Afro-Trinidadians. The stage at diagnosis varies across cancer types and gender.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pancreáticas , Masculino , Femenino , Humanos , Trinidad y Tobago/epidemiología , Estudios Retrospectivos , Incidencia
7.
Obstet Med ; 16(1): 48-51, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37139512

RESUMEN

Purpose: Haemorrhage, preeclampsia and sepsis are the leading causes of renal dysfunction in women with a maternal nearmiss(MNM) complication. The study aimed to assess the prevalence, pattern and follow up of these women. Methods: This was a hospital based prospective observational study, conducted over one year. All women with a MNM leading to acute kidney injury (AKI) were analysed for fetomaternal outcomes and renal function at 1 year of followup. Results: The incidence of MNM was 43.04 per 1000 livebirths. 18.2% women developed AKI. 51.1% women developed AKI in the puerperal period. Most common cause of AKI was haemorrhage seen in 38.3% women. The majority of women had s.creatinine between 2.1 to 5 mg/dl and 44.68% required dialysis. 80.8% women recovered fully when the treatment was initiated within 24 h. One patient underwent renal transplant. Conclusion: Early diagnosis and treatment of AKI results in full recovery.

8.
NMR Biomed ; 36(6): e4894, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36543742

RESUMEN

Here, we describe and assess the potential of 14 newly synthesized imidazole-4,5-dicarboxyamides (I45DCs) for pH and perfusion imaging. A number of these aromatic compounds possess large labile proton chemical shifts (up to 7.7 ppm from water) because of their intramolecular hydrogen bonds and a second labile proton to allow for chemical exchange saturation transfer (CEST) signal ratio-based pH measurements. We have found that the contrast produced is strong for a wide range of substitutions and that the inflection points in the CEST signal ratio versus pH plots used to generate concentration-independent pH maps can be adjusted based on these subsitutions to tune the pH range that can be measured. These I45DC CEST agents have advantages over the triiodobenzenes currently employed for tumor and kidney pH mapping, both preclinically and in initial human studies. Finally, as CEST MRI combined with exogenous contrast has the potential to detect functional changes in the kidneys, we evaluated our highest performing anionic compound (I45DC-diGlu) on a unilateral urinary obstruction mouse model and observed lower contrast uptake in the obstructed kidney compared with the unobstructed kidney and that the unobstructed kidney displayed a pH of ~ 6.5 while the obstructed kidney had elevated pH and an increased range in pH values. Based on this, we conclude that the I45DCs have excellent imaging properties and hold promise for a variety of medical imaging applications, particularly renal imaging.


Asunto(s)
Medios de Contraste , Protones , Ratones , Animales , Humanos , Concentración de Iones de Hidrógeno , Medios de Contraste/química , Fantasmas de Imagen , Imagen por Resonancia Magnética/métodos , Imidazoles , Imagen de Perfusión
10.
NMR Biomed ; 36(6): e4715, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35187749

RESUMEN

Since the inception of CEST MRI in the 1990s, a number of compounds have been identified as suitable for generating contrast, including paramagnetic lanthanide complexes, hyperpolarized atom cages and, most interesting, diamagnetic compounds. In the past two decades, there has been a major emphasis in this field on the identification and application of diamagnetic compounds that have suitable biosafety profiles for usage in medical applications. Even in the past five years there has been a tremendous growth in their numbers, with more and more emphasis being placed on finding those that can be ultimately used for patient studies on clinical 3 T scanners. At this point, a number of endogenous compounds present in tissue have been identified, and also natural and synthetic organic compounds that can be administered to highlight pathology via CEST imaging. Here we will provide a very extensive snapshot of the types of diamagnetic compound that can generate CEST MRI contrast, together with guidance on their utility on typical preclinical and clinical scanners and a review of the applications that might benefit the most from this new technology.


Asunto(s)
Medios de Contraste , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos
11.
Magn Reson Med ; 89(1): 343-355, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36089805

RESUMEN

PURPOSE: To assess the potential of DCE MR CEST urography for assessing renal function in mice with unilateral ureter obstruction (UUO) by simultaneous pH and renal uptake/clearance measurements following injection of iopamidol. METHODS: The right ureter of nine mice was obstructed via suture ligation. The animals were imaged at day 1, 2, and 3 post-obstruction on an 11.7T MRI scanner. Ninety-six sets of saturated CEST images at 4.3 and 5.5 ppm were collected. Renal pH values were obtained by calculating the signal ratio for these two frequencies and using a pH calibration curve. Renal time activity curves were measured as a percentage change in the post-injection CEST signal at 4.3 ppm relative to the average pre-injection signal. RESULTS: For the healthy mice, the time activity curves of both kidneys were nearly identical and displayed rapid excretion of contrast. For the UUO mice, the dynamic CEST curves for the obstructed kidneys displayed prolonged time to peak (TTP) values and delayed contrast excretion compared with the contralateral (CL) kidneys. Renal pH maps of the healthy animals showed similar acidic values for both kidneys (pH 6.65 ± 0.04 vs 6.67 ± 0.02), whereas in the obstructed kidneys there was a significant increase in pH values compared with the CL kidneys (pH 6.67 ± 0.08 vs 6.79 ± 0.11 in CL and UUO kidneys, respectively). CONCLUSION: Our findings indicate that DCE-MR-CEST urography can detect changes in renal uptake/excretion and pH homeostasis and distinguish between obstructed and unobstructed kidney as early as 1 day after UUO.


Asunto(s)
Uréter , Obstrucción Ureteral , Animales , Ratones , Obstrucción Ureteral/diagnóstico por imagen , Riñón/diagnóstico por imagen , Riñón/fisiología , Imagen por Resonancia Magnética/métodos , Concentración de Iones de Hidrógeno , Urografía
12.
Front Pharmacol ; 13: 1025591, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532778

RESUMEN

Background: Ayurveda, the indigenous medical system of India, has chemosensory property (rasa) as one of its major pharmacological metric. Medicinal plants have been classified in Ayurveda under six rasas/tastes-sweet, sour, saline, pungent, bitter and astringent. This study has explored for the first time, the use of Electronic tongue for studies of rasa-based classification of medicinal plants. Methods: Seventy-eight medicinal plants, belonging to five taste categories (sweet, sour, pungent, bitter, astringent) were studied along with the reference taste standards (citric acid, hydrochloric acid, caffeine, quinine, L-alanine, glycine, ß-glucose, sucrose, D-galactose, cellobiose, arabinose, maltose, mannose, lactose, xylose). The studies were carried out with the potentiometry-based Electronic tongue and the data was analysed using Principle Component Analysis, Discriminant Function Analysis, Taste Discrimination Analysis and Soft Independent Modeling of Class Analogy. Results: Chemosensory similarities were observed between taste standards and the plant samples-citric acid with sour group plants, sweet category plants with sucrose, glycine, ß-glucose and D-galactose. The multivariate analyses could discriminate the sweet and sour, sweet and bitter, sweet and pungent, sour and pungent plant groups. Chemosensory category of plant (classified as unknown) could also be identified. Conclusion: This preliminary study has indicated the possibility of fingerprinting the chemosensory-based ayurvedic classification of medicinal plants using E-tongue coupled with multivariate statistical analysis.

13.
Indian J Ophthalmol ; 70(12): 4238-4243, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36453323

RESUMEN

Purpose: To report the demographic profile of patients registered through e-Sanjeevani OPD seeking teleophthalmology services. Methods: This was a cross-sectional data analysis of patients with ocular complaints registered through the e-Sanjeevani platform at a tertiary care center. It was a doctor-to-doctor consultation, where teleophthalmology consultants provided teleconsultation services at subcenters (SCs), primary health centers (PHCs), and community health centers (CHCs). Data regarding the patient's age, gender, residential address, provisional diagnosis, and treatment prescribed were recorded from May 2021 to February 2022 (9 months). Results: In total, 5138 patients were teleconsulted from the mean age of the patients was 37.64 ± 19.34 years. Among these patients, 44% were males and 56% were females. Most of the teleconsultation calls were made from Palwal district (19.8%), followed by Hisar (14.5%) and Sonipat. The most common provisional diagnosis was dry eyes (21%), followed by allergic conjunctivitis (18%), refractive error (15%), and cataract (14%). These constituted approximately 70% of the diagnosis made through teleconsultations. The rest of the eye problems were diagnosed as stye, blepharitis, nasolacrimal duct obstruction, pterygium, subconjunctival hemorrhage, etc., The majority of the patients were managed medically (56.6%) and approximately 11.6% of the patients were referred for surgical intervention. Conclusion: e-Sanjeevani is an effective way to provide teleconsultations to patients in remote locations. The majority of the patients seeking ophthalmology consultations can be managed conservatively. Patients requiring surgical intervention can be referred timely, thus avoiding any delay in treatment.


Asunto(s)
Obstrucción del Conducto Lagrimal , Conducto Nasolagrimal , Oftalmología , Pterigion , Consulta Remota , Telemedicina , Femenino , Masculino , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Estudios Transversales , Estudios Retrospectivos , Demografía
15.
Sensors (Basel) ; 22(15)2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35957340

RESUMEN

Label-free field-effect transistor-based immunosensors are promising candidates for proteomics and peptidomics-based diagnostics and therapeutics due to their high multiplexing capability, fast response time, and ability to increase the sensor sensitivity due to the short length of peptides. In this work, planar junctionless field-effect transistor sensors (FETs) were fabricated and characterized for pH sensing. The device with SiO2 gate oxide has shown voltage sensitivity of 41.8 ± 1.4, 39.9 ± 1.4, 39.0 ± 1.1, and 37.6 ± 1.0 mV/pH for constant drain currents of 5, 10, 20, and 50 nA, respectively, with a drain to source voltage of 0.05 V. The drift analysis shows a stability over time of -18 nA/h (pH 7.75), -3.5 nA/h (pH 6.84), -0.5 nA/h (pH 4.91), 0.5 nA/h (pH 3.43), corresponding to a pH drift of -0.45, -0.09, -0.01, and 0.01 per h. Theoretical modeling and simulation resulted in a mean value of the surface states of 3.8 × 1015/cm2 with a standard deviation of 3.6 × 1015/cm2. We have experimentally verified the number of surface sites due to APTES, peptide, and protein immobilization, which is in line with the theoretical calculations for FETs to be used for detecting peptide-protein interactions for future applications.


Asunto(s)
Técnicas Biosensibles , Transistores Electrónicos , Técnicas Biosensibles/métodos , Electricidad , Inmunoensayo , Dióxido de Silicio
16.
J Ayurveda Integr Med ; 12(2): 238-244, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33551338

RESUMEN

BACKGROUND: Although Electronic tongue is used in pharmaceutical, food and beverage industries for objective evaluation of taste, its use in medicinal plants from an ayurvedic perspective is novel. Control experiments are therefore necessary to standardise and optimise parameters. OBJECTIVE: The aim is to optimise the use of solvent and standardise sample concentration for study of plants from an ayurvedic standpoint of rasa. The major objectives are two-fold: (i) evaluate sensor response to different types of solvent water (ii) explore use of E-tongue in taste ranking of medicinal plants used in ayurveda. MATERIALS AND METHODS: Single, double and triple distilled, reverse osmosis and milliQ waters were evaluated separately and as a medium for preparing plant extracts. For taste ranking, standard addition method using d-glucose as sweet taste standard was used for different brands of mango juices (case in point study) and eight medicinal plants from sweet category. The effect of sample concentration and taste standard on taste ranking were evaluated. RESULTS: MQ and TD water demonstrated similar organoleptic properties whereas plant extracts prepared in DD and MQ water showed maximum taste-based differentiation. The mango juices were taste discriminated by E-tongue and ranked based on their sweetness scores. The relative ranking of plant samples showed concentration dependence and also varied with the concentration range of taste standard. CONCLUSION: Milli-Q and double distilled water can be used for E-tongue studies of medicinal plants. While the results open up the possibility of taste ranking of medicinal plants, they also demonstrate the importance of standardising and optimising the concentration of samples and taste standards in the context of ayurvedic rasa based studies.

17.
J Ayurveda Integr Med ; 12(2): 234-237, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33514460

RESUMEN

There is growing interest in understanding how ayurveda, the indigenous medical system of India, uses plants for therapeutic purpose. The aim of this two parts article is to explore how the analytical technique of Electronic tongue (E-tongue) can be used for studying rasa, one of the major ayurvedic parameter in the study of medicinal and nutritional plants. Although E-tongue is widely used in pharmaceutical, food and beverage industries for objective evaluation of taste, its use in plants from an ayurvedic perspective is novel. This first of the two parts article introduces the technique of E-tongue, positioning it in context for the following part. The latter discusses crucial control experiments required prior using E-tongue for studies on medicinal plants from an ayurvedic standpoint.

18.
J Ayurveda Integr Med ; 10(2): 94-101, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29306573

RESUMEN

BACKGROUND: Information from Ayurveda meeting the analytical challenges of modern technology is an area of immense relevance. Apart from the cerebral task of bringing together two different viewpoints, the question at the pragmatic level remains 'who benefits whom'. OBJECTIVE: The aim is to highlight the challenges in integration of information (Ayurvedic) and technology using test examples of Nuclear Magnetic Resonance (NMR) metabolomics and anti-HIV-1 potential of select Ayurvedic medicinal plants. The other value added objective is implications and relevance of such work for Ayurveda. MATERIALS AND METHODS: Six medicinal plants (Azadirachta indica, Tinospora cordifolia, Swertia chirata, Terminalia bellerica, Zingiber officinale and Symplocos racemosa) were studied using high resolution proton NMR spectroscopy based metabolomics and also evaluated for anti-HIV-1 activity on three pseudoviruses (ZM53 M.PB12, ZM109F.PB4, RHPA 4259.7). RESULTS: Of the six plants, T. bellerica and Z. officinale showed minimum cell cytotoxicity and maximum anti-HIV-1 potential. T. bellerica was effective against all the three HIV-1 pseudoviruses. Untargeted NMR profiling and multivariate analyses demonstrated that the six plants, all of which had different Ayurvedic pharmacological properties, showed maximum differences in the aromatic region of the spectra. CONCLUSION: The work adds onto the list of potential plants for anti-HIV-1 drug molecules. At the same time, it has drawn attention to the different perspectives of Ayurveda and Western medicine underscoring the inherent limitations of conceptual bilinguism between the two systems, especially in the context of medicinal plants. The study has also highlighted the potential of NMR metabolomics in study of plant extracts as used in Ayurveda.

19.
Biosens Bioelectron ; 126: 15-22, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30388549

RESUMEN

Advances in nanostructured materials have facilitated the development of novel sensitive techniques for detection of environmental and clinical analytes. There is immense need for development of devices that can detect analytes at concentrations as low as few pg mL-1. The comparable size of nanostructured materials and biomolecules enabled the integration of biological systems with nanometer sized structures. Herein, we demonstrate a Zinc Oxide nanorods (ZnONRs) integrated ultrasensitive label-free biosensor with femtomolar (0.01 pg mL-1) sensitivity for the endocrine disruptor 17ß-Estradiol (E2). The ZnONRs, average width 50 nm and length 325 nm, were grown on the silver electrode surface (Ag-ZnONRs). Monoclonal antibodies of E2 (mAb-E2) were covalently immobilized on ZnONRs surface and measured using electrochemical impedance spectroscopy (EIS). A linear detection range of 0.1-200 pg mL-1 for E2 with R2 = 0.99 and % RSD = 4.35 (n = 3, assay volume 90 µL) was achieved for the developed nano-sensing system. A significant enhancement in the sensitivity was achieved in the presence of ZnONRs, enabling the limit of quantification down to 0.1 pg mL-1 with 2.7 % capacitance change per decade. In addition, a further increase in sensitivity due to assay volume reduction (20 µL) was observed enabling further scope of miniaturization.


Asunto(s)
Técnicas Biosensibles/instrumentación , Estradiol/análisis , Nanotubos/química , Contaminantes Químicos del Agua/análisis , Óxido de Zinc/química , Anticuerpos Inmovilizados/química , Técnicas Electroquímicas/instrumentación , Electrodos , Diseño de Equipo , Inmunoensayo/instrumentación , Límite de Detección , Nanotubos/ultraestructura , Agua/análisis
20.
Recent Pat Drug Deliv Formul ; 9(3): 201-12, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26072957

RESUMEN

Oral immunization with vaccines has proven its worth by eradicating several diseases worldwide, yet only few oral vaccines exist in practice. This is because the oral route is plagued with various challenges for successful delivery of vaccines, such as limited absorption and high degradation in the gastrointestinal tract. Tremendous research in the last decade has made bilosomes a potential carrier system for oral immunization. Bilosomes with its name derived from bile salts (which is one of its major constituent), is a 'niosome-like' colloidal carrier. The collective information addressed through this review, convincingly points out that factors such as size, composition (type of bile salt, and lipid), charge, ligand attached, etc., which show significant influence on the type, and amount of immunity developed following the oral administration of bilosomes. These bile salts containing vesicular carriers have been employed to treat various serious conditions. Some of these methods have been successfully established into patents. Bilosomes loaded with antigens, peptides and other biological materials for the treatment of influenza, heart failure, diuresis, Irritable Bowel Syndrome (IBS) and other gastrointestinal disorders have been discussed in the present article.


Asunto(s)
Ácidos y Sales Biliares/química , Portadores de Fármacos , Inmunización , Tecnología Farmacéutica/métodos , Vacunas/administración & dosificación , Administración Oral , Animales , Coloides , Humanos , Liposomas , Vacunas/química , Vacunas/inmunología
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