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2.
Int J Cardiol ; 393: 131364, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37722456

RESUMEN

BACKGROUND: Despite the well-established benefits of cardiac rehabilitation (CR) for patients with cardiovascular disease (CVD), participation in CR remain low. Virtual CR programs present a unique opportunity to promote utilization. To date, few virtual CR cohorts have been analyzed for compliance. This study aims to determine factors that predict compliance within a large virtual CR program in the United States. METHODS: We analyzed 1409 patients enrolled in the Kaiser Permanente Mid-Atlantic States Virtual CR program that consists of 12 CR sessions via telephone. Demographic characteristics, as well as body weight, blood pressure, HbA1c level, and smoking status were collected at admission. Patients were further classified by CVD diagnosis codes. Compliance was defined as at least 75% (9/12 sessions) attendance. Data was analyzed using simple and multiple regression models with significance defined as P < 0.05. RESULTS: Age was the single strongest predictor for virtual CR compliance (adjusted R2 = 0.58; P < 0.001), and non-compliant patients were younger. HbA1C level, CVD diagnosis codes, and smoking status each moderately predicted compliance (adjusted R2 = 0.48, 0.42, and 0.31, respectively; P < 0.001). Smoking and HbA1C level combined in a multiple regression model significantly improved prediction of compliance (adjusted R2 = 0.79, P < 0.01). Sex, baseline weight or hypertension were not significant predictors of CR compliance. CONCLUSIONS: Age, diabetes, CVD diagnoses, smoking status at admission are independent predictors of compliance in a large virtual CR program. Targeted intervention could be designed accordingly to improve CR compliance.


Asunto(s)
Rehabilitación Cardiaca , Enfermedades Cardiovasculares , Humanos , Estados Unidos , Hemoglobina Glucada , Cooperación del Paciente , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Fumar
3.
Biosens Bioelectron ; 235: 115359, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37187062

RESUMEN

Photoelectrochemical (PEC) signal transduction is of great interest for ultrasensitive biosensing; however, signal-on PEC assays that do not require target labeling remain elusive. In this work, we developed a signal-on biosensor that uses nucleic acids to modulate PEC currents upon target capture. Target presence removes a biorecognition probe from a DNA duplex carrying a gold nanoparticle, bringing the gold nanoparticle in direct contact to the photoelectrode and increasing the PEC current. This assay was used to develop a universal bacterial detector by targeting peptidoglycan using an aptamer, demonstrating a limit-of-detection of 82 pg/mL (13 pM) in buffer and 239 pg/mL (37 pM) in urine for peptidoglycan and 1913 CFU/mL forEscherichia coliin urine. When challenged with a panel of unknown targets, the sensor identified samples with bacterial contamination versus fungi. The versatility of the assay was further demonstrated by analyzing DNA targets, which yielded a limit-of-detection of 372 fM.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Técnicas Electroquímicas , Oro , Peptidoglicano , ADN , Oligonucleótidos
4.
J Family Med Prim Care ; 11(9): 5696-5699, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36505645

RESUMEN

Insulinoma is a rare pancreatic neuroendocrine tumour (PNET) with an incidence rate of 4 per million population, and the most common cause of hypoglycaemia due to endogenous hyperinsulinism. We present the story of a 61-year-old male, who was extensively evaluated at many hospitals for his symptoms of giddiness, uneasiness and recurrent black outs for the last 3 months, his symptoms disappearing with a carbohydrate rich meal or sweets. Random sugar and fasting sugar values noted were low, with elevated insulin and C-peptide levels. Diagnosis of insulinoma was confirmed by a DOTA PET scan involving the tail of the pancreas and then surgically removed. Early detection is crucial for early surgery to allay symptoms. We describe our diagnostic and treatment plan with reference to previously published reports.

5.
Nat Commun ; 13(1): 6888, 2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36371423

RESUMEN

Understanding exotic forms of magnetism in quantum spin systems is an emergent topic of modern condensed matter physics. Quantum dynamics can be described by particle-like carriers of information, known-as quasiparticles that appear from the collective behaviour of the underlying system. Spinon excitations, governing the excitations of quantum spin-systems, have been accurately calculated and precisely verified experimentally for the antiferromagnetic chain model. However, identification and characterization of novel quasiparticles emerging from the topological excitations of the spin system having periodic exchange interactions are yet to be obtained. Here, we report the identification of emergent composite excitations of the novel quasiparticles doublons and quartons in spin-1/2 trimer-chain antiferromagnet Na2Cu3Ge4O12 (having periodic intrachain exchange interactions J1-J1-J2) and its topologically protected quantum 1/3 magnetization-plateau state. The characteristic energies, dispersion relations, and dynamical structure factor of neutron scattering as well as macroscopic quantum 1/3 magnetization-plateau state are in good agreement with the state-of-the-art dynamical density matrix renormalization group calculations.

6.
J Family Med Prim Care ; 11(5): 2231-2233, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35800512

RESUMEN

Vaccination is supposed to be the most reliable means to end the COVID 19 pandemic, but recently there have been reports of thrombosis and thrombocytopenia in patients receiving the vaccine especially ChAdOx1 nCoV-19 (AstraZeneca University of Oxford and Serum Institute of India). This has been termed as vaccine-induced immune thrombotic thrombocytopenia (VITT), thrombosis with thrombocytopenia syndrome (TTS) and vaccine-induced prothrombotic immune thrombocytopenia (VIPIT). This is a challenging situation and patients are treated with Fondaparinaux and Rivaroxaban after thrombocytopenia is corrected. Herewith, we report a case of VITT who presented to our hospital and was successfully treated over a weeks' time.

7.
J Family Med Prim Care ; 11(12): 7968-7971, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36994025

RESUMEN

Crohn's disease may affect individuals across all age groups. Usually, it tends to start at a young age, hence late onset Crohn's disease may be difficult to diagnose. The incidence of late-onset inflammatory bowel disease in the United States is 4 to 8 per 100,000 per year. The incidence of Crohn's disease is more in the United States and Europe and less in Asia and Africa. This makes it more challenging to suspect Crohn's disease in an elderly individual of Indian origin. It may be confused with Irritable bowel syndrome or Intestinal tuberculosis.

8.
Materials (Basel) ; 16(1)2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36614500

RESUMEN

OBJECTIVES: From the treatment of damaged teeth to replacing missing teeth, dental biomaterials cover the scientific interest of many fields. Dental biomaterials are one of the implants whose effective life depends vastly on their material and manufacturing techniques. The purpose of this review is to summarize the important aspects for metallic dental implants from biomedical, mechanical and materials science perspectives. The review article will focus on five major aspects as mentioned below. Tooth anatomy: Maximizing the implant performance depends on proper understanding of human tooth anatomy and the failure behavior of the implants. Major parts from tooth anatomy including saliva characteristics are explored in this section. Wear mechanisms: The prominent wear mechanisms having a high impact on dental wear are abrasive, adhesive, fatigue and corrosion wear. To imitate the physiological working condition of dental implants, reports on the broad range of mastication force and various composition of artificial saliva have been included in this section, which can affect the tribo-corrosion behavior of dental implants. Dental implants classifications: The review paper includes a dedicated discussion on major dental implants types and their details for better understanding their applicability and characteristics. Implant materials: As of today, the most established dental implant materials are SS316L, cobalt chrome alloy and titanium. Detailed discussion on their material properties, microstructures, phase transformations and chemical compositions have been discussed here. Manufacturing techniques: In terms of different production methods, the lost wax casting method as traditional manufacturing is considered. Selective Laser Melting (SLM) and Directed Energy Deposition (DED) as additive manufacturing techniques (AM) have been discussed. For AM, the relationships between process-property-performance details have been explored briefly. The effectiveness of different manufacturing techniques was compared based on porosity distribution, mechanical and biomechanical properties. SUMMARY: Despite having substantial research available on dental implants, there is a lack of systematic reviews to present a holistic viewpoint combining state-of-the-art from biomedical, mechanical, materials science and manufacturing perspectives. This review article attempts to combine a wide variety of analyzing approaches from those interdisciplinary fields to deliver deeper insights to researchers both in academia and industry to develop next-generation dental implants.

9.
Anal Chem ; 93(48): 15913-15921, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34806869

RESUMEN

With an increased understanding of the role of microRNAs (miRNAs) in cancer evolution, there is a growing interest in the use of these non-coding nucleic acids in cancer diagnosis, prognosis, and treatment monitoring. miRNAs embedded in extracellular vesicles (EVs) are of particular interest given that circulating EVs carry cargo that are strongly correlated to their cells of origin such as tumor cells while protecting them from degradation. As such, there is a tremendous interest in new simple-to-operate vesicular microRNA analysis tools for widespread use in performing liquid biopsies. Herein, we present a two-step competitive hybridization assay that is rationally designed to translate low microRNA concentrations to large electrochemical signals as the measured signal is inversely proportional to the microRNA concentration. Using this assay, with a limit-of-detection of 122 aM, we successfully analyzed vesicular miRNA 200b from prostate cancer cell lines and human urine samples, demonstrating the expected lower expression levels of miRNA 200b in the EVs from prostate cancer cells and in the prostate cancer patient's urine samples compared to healthy patients and non-tumorigenic cell lines, validating the suitability of our approach for clinical analysis.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Neoplasias de la Próstata , Humanos , Biopsia Líquida , Masculino , MicroARNs/genética , Pronóstico , Neoplasias de la Próstata/genética
10.
Angew Chem Int Ed Engl ; 60(13): 7316-7322, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33403773

RESUMEN

Photoelectrochemical biosensors hold great promise for sensitive bioanalysis; however, similar to their electrochemical analogues, they are highly affected by the variable backgrounds caused by biological matrices. We developed a new PEC biosensing strategy that uses differential signal generation, combining signals from two separate but correlated binding events on the biosensor, for improving the limit-of-detection, sensitivity, and specificity of PEC DNA biosensors in biological samples. In this assay, the binding of unlabeled target DNA is followed by the capture of a signal amplification barcode featuring a plasmonic nanoparticle. The interaction of the plasmonic barcode with the semiconductive building blocks of the biosensor results in significant signal amplification, and together with differential signal processing enhances the limit of detection and sensitivity of the assay by up to 15- and three-fold, respectively, compared to the previously-used PEC assays with a single binding event, demonstrating a limit of detection of 3 fM.


Asunto(s)
Técnicas Biosensibles , Código de Barras del ADN Taxonómico , ADN/análisis , Técnicas Electroquímicas , Procesos Fotoquímicos
11.
ACS Appl Mater Interfaces ; 12(33): 36895-36905, 2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32814377

RESUMEN

As dynamic biorecognition agents such as functional nucleic acids become widely used in biosensing, there is a need for ultrasensitive signal transduction strategies, beyond fluorescence, that are robust and stable for operation in heterogeneous biological samples. Photoelectrochemical readout offers a pathway toward this goal as it offers the simplicity and scalability of electrochemical readout, in addition to compatibility with a broad range of nanomaterials used as labels for signal transduction. Here, a differential photoelectrochemical biosensing approach is reported, in which DNA nanospacers are used to program the response of two sensing channels. The differences in the motional dynamics of DNA probes immobilized on different channels are used to control the interaction between Au and TiO2 nanoparticles positioned at the two ends of the DNA nanospacer to achieve differential signal generation. Depending on the composition of the DNA constructs (fraction of the DNA sequence i.e., double-stranded), the channels can be programmed to produce a signal-on or a signal-off response. Incident photon-to-current conversion efficiency, UV-vis spectroscopy, and flat-band potential measurement indicate that direct transfer of electrons between metallic and semiconductive nanoparticles is responsible for the signal-on response, and incident light absorption and steric hindrance are responsible for the signal-off response. The differential photoelectrochemical signal readout developed here increases the device sensitivity by up to three times compared to a single channel design and demonstrates a limit of detection of 800 aM.


Asunto(s)
Compuestos de Boro/química , ADN/análisis , Oro/química , Nanopartículas/química , Semiconductores , Titanio/química , Secuencia de Bases , Técnicas Biosensibles , Técnicas Electroquímicas , Electrodos , Transporte de Electrón , Límite de Detección , Procesos Fotoquímicos , Relación Señal-Ruido , Propiedades de Superficie
12.
J Phys Condens Matter ; 32(33): 335601, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32244238

RESUMEN

A Heisenberg spin-s chain with alternating ferromagnetic (FM) ([Formula: see text]) and antiferromagnetic ([Formula: see text]) nearest-neighbor (NN) interactions, exhibits the dimer and spin-2s Haldane phases in the limits [Formula: see text] and [Formula: see text] respectively. These two phases are understood to be topologically equivalent. Induction of the frustration through the next NN FM interaction ([Formula: see text]) produces a very rich quantum phase diagram. With frustration, the whole phase diagram is divided into a FM and a nonmagnetic (NM) phase. For s = 1/2, the full NM phase is seen to be of Haldane-dimer type, but for s > 1/2, a spiral phase comes between the FM and the Haldane-dimer phases. The study of a suitably defined string-order parameter and spin-gap at the phase boundary indicates that the Haldane-dimer and spiral phases have different topological characters. We also find that, along the [Formula: see text] line in the NM phase, an NN dimer state is the exact groundstate, provided [Formula: see text] where κ ⩽ s + h for applied magnetic field h. Without magnetic field, the position of J C is on the FM-NM phase boundary when s = 1/2, but for s > 1/2, the location of J C is on the phase separation line between the Haldane-dimer and spiral phases.

13.
Front Chem ; 7: 617, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31572709

RESUMEN

Detection and quantification of biologically-relevant analytes using handheld platforms are important for point-of-care diagnostics, real-time health monitoring, and treatment monitoring. Among the various signal transduction methods used in portable biosensors, photoelectrochemcial (PEC) readout has emerged as a promising approach due to its low limit-of-detection and high sensitivity. For this readout method to be applicable to analyzing native samples, performance requirements beyond sensitivity such as specificity, stability, and ease of operation are critical. These performance requirements are governed by the properties of the photoactive materials and signal transduction mechanisms that are used in PEC biosensing. In this review, we categorize PEC biosensors into five areas based on their signal transduction strategy: (a) introduction of photoactive species, (b) generation of electron/hole donors, (c) use of steric hinderance, (d) in situ induction of light, and (e) resonance energy transfer. We discuss the combination of strengths and weaknesses that these signal transduction systems and their material building blocks offer by reviewing the recent progress in this area. Developing the appropriate PEC biosensor starts with defining the application case followed by choosing the materials and signal transduction strategies that meet the application-based specifications.

14.
Analyst ; 144(5): 1850, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30714600

RESUMEN

Correction for 'Solution-processed wrinkled electrodes enable the development of stretchable electrochemical biosensors' by Yuting Chan et al., Analyst, 2019, 144, 172-179.

15.
Analyst ; 144(1): 172-179, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30358778

RESUMEN

Wearable biosensors are critical for enabling real-time and continuous health monitoring and disease management. Conductors that retain their conductivity under strain are an essential building block of these systems. Strategies based on stretchable materials or structures have enabled the development of electrodes that can withstand impressive strains before loss of conductivity. In spite of this, it remains challenging to develop three-dimensional and high surface area electrodes that combine stretchability with high analytical sensitivity. Here, we develop stretchable electrochemical biosensors using solution-processed wrinkled gold electrodes. Wrinkling enhances the surface area of the electrodes and allows glucose to be detected with a sensitivity of 750-810 µA M-1 cm-2. Furthermore, wrinkling enables electrodes to be strained by up to 230% without significant loss in conductivity.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Oro/química , Técnicas Biosensibles/métodos , Elasticidad , Conductividad Eléctrica , Técnicas Electroquímicas/métodos , Electrodos , Glucosa/análisis , Límite de Detección , Poliestirenos/química
17.
ACS Appl Mater Interfaces ; 10(37): 31178-31185, 2018 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-30192501

RESUMEN

Photoelectrochemical (PEC) biosensors, with optical biasing and electrochemical readout, are expected to enhance the limit-of-detection of electrochemical biosensors by lowering their background signals. However, when PEC transducers are functionalized with biorecognition layers, their current significantly decreases, which reduces their signal-to-noise ratio and dynamic range. Here, we develop and investigate a wrinkled conductive scaffold for loading photoactive quantum dots into an electrode. The wrinkled photoelectrodes demonstrate an order of magnitude enhancement in the magnitude of the transduced PEC current compared to their planar counterparts. We engineer PEC biosensors by functionalizing the wrinkled photoelectrodes with nucleic acid capture probes. We challenge the sensitivity of the wrinkled and planar biosensors with various concentrations of DNA target and observe a 200 times enhancement in the limit-of-detection for wrinkled versus planar electrodes. In addition to enhanced sensitivity, the wrinkled PEC biosensors are capable of distinguishing between fully complementary and targets with a single base-pair mismatch, demonstrating the suitability of these biosensors for use in clinical diagnostics.


Asunto(s)
Técnicas Biosensibles/métodos , ADN , Técnicas Electroquímicas , Técnicas de Diagnóstico Molecular/métodos , ADN/análisis , Electrodos , Fotoquímica , Puntos Cuánticos/química
18.
Indian J Hematol Blood Transfus ; 34(2): 310-313, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29622875

RESUMEN

Study of different parameters of cord blood usually reflects neonatal health status. One of the widely used system for assessing neonatal health is APGAR score. It is assed at 1 and 5 min from baby's birth. Immediate medical care may improve 5 min score of neonate who showed poor score at 1 min. The main objective of this study is to establish whether any correlation exists between complete hemogram and iron profile with APGAR score and gravid of mother. Cord blood was collected from 96 new born, delivered vaginally, mothers having no chronic medical disease. Different parameters of complete hemogram were assessed along with iron profile and statistical analysis was done by Graph pad Instat3 soft ware. Statistically significant correlation exists between APGAR score (5 min) and MCV (p = 0.005), MCHC (p = 0.016), nRBC (p = 0.002), platelet count (p = 0.001), RDW (p = 0.001). Statistically weak correlation exists between TLC (p = 0.08). Comparing complete blood count with gravid of mother by unpaired t test significant correlation was obtained for HCT (p = 0.035) and RDW (p = 0.03). Apgar score and complete hemogram from cord blood are both non-invasive procedure which help us to asses fetal wellbeing as well as requirement of immediate management. Further more studies are essential to establish the relationship.

19.
J Hum Reprod Sci ; 11(1): 10-18, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29681710

RESUMEN

BACKGROUND: Stress is an invisible factor affecting modern day living and is strongly associated with many disease pathogenesis including polycystic ovarian syndrome (PCOS) in women. PCOS is the most frequent endocrinological disorder that affects women of reproductive age, leading to metabolic dysfunction and body composition alterations. Salivary amylase and cortisol are major stress mediators that have been implicated in PCOS. However, their role in altering body composition in PCOS is yet to be deciphered. AIM: The present study aimed at understanding the relation between stress-associated factors and alterations in body composition among PCOS patients. DESIGN: This study enrolled a total of 100 patients (PCOS) and 60 age-matched controls. The female patients were of ages between 13 and 30 years. MATERIALS AND METHODS: Standard assay kits were used to evaluate the α-amylase activity and cortisol level in saliva. The participants were chosen on the basis of the Rotterdam American Society for Reproductive Medicine/European Society of Human Reproduction criteria. Saliva was collected from each participant as per the protocol of Salimetrics, USA. STATISTICAL ANALYSIS: Statistical analysis was performed using SPSS version 20 for Windows. The quantitative variables are described as mean ± standard deviation. P < 0.05 was considered significant. RESULTS: Increased salivary cortisol level and α-amylase activity were seen in the PCOS population as compared to age-matched controls suggesting patients a sustained stress scenario in their system. Moreover, overweight PCOS participants reflected higher amylase activity than the lean patients participants. Pulse rate, body mass index (BMI), visceral adiposity, and waist-hip ratio (WHR) was considerably higher in the PCOS patients participants compared to controls. A significant correlation could be drawn between the α-amylase activity and BMI or WHR, respectively, among PCOS patients. These observations indicate a strong link between the stress marker and alterations in the body composition parameters of PCOS patients participants. CONCLUSION: Higher prevalence of stress in PCOS patients participants has a critical role in their altered body composition.

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