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1.
Nano Lett ; 24(25): 7578-7583, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38742810

RESUMO

Material absorption is a key limitation in nanophotonic systems; however, its characterization is often obscured by scattering and diffraction. Here we show that nanomechanical frequency spectroscopy can be used to characterize material absorption at the parts per million level and use it to characterize the extinction coefficient κ of stoichiometric silicon nitride (Si3N4). Specifically, we track the frequency shift of a high-Q Si3N4 trampoline in response to laser photothermal heating and infer κ from a model including stress relaxation and both conductive and radiative heat transfer. A key insight is the presence of two thermalization time scales: rapid radiative cooling of the Si3N4 film and slow parasitic heating of the Si chip. We infer κ ∼ 0.1-1 ppm for Si3N4 in the 532-1550 nm wavelength range, matching bounds set by waveguide resonators. Our approach is applicable to diverse photonic materials and may offer new insights into their potential.

2.
Cureus ; 16(1): e52435, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38371166

RESUMO

A 100 trillion bacteria, viruses, fungi, and archaea make up the human gut microbe. It has co-evolved with its human host and carries out essential tasks that improve general health. The relationship between gastrointestinal microbes and human health has been a growing field of interest and research in recent times. The gastrointestinal microbes are connected by complex networks and connections, and the host has given birth to the gut-microbe-brain axis, which shows the crucial effect that this circumstance could have on the health and diseases of the brain and spinal cord (or the central nervous system [CNS]). The microbe and the CNS interact bi-directionally via autonomic, neuroendocrine, gastrointestinal, and immune system pathways. The gut microbe has been connected to a range of gastrointestinal and extra-gastrointestinal diseases. The recent investigation supports the suspicion that the gut-microbe-brain axis could play a role in neuropsychiatric disorders including depression, dementia, post-traumatic stress disorder, anxiousness, bipolar disorder, schizophrenia, and obsessive-compulsive disorder, alongside chronic host illnesses such as obesity, diabetes, and inflammation. Studies point to gut microorganisms as possible biomarkers for a wide range of mental health issues. Changes in the gut microbe may be a crucial factor in the onset and advancement of non-alcoholic fatty liver damage. Gut microbes have been seen to influence microglia's response to the CNS's regional signals and thus to pain and inflammation. Data suggest that altering the gut microbe in those with chronic pain may be a successful method for reducing pain. Numerous investigations have documented alterations in the gut microbes made in Alzheimer patients and schizophrenic patients. The risk of breast cancer can be reduced by restoring gut microbe homeostasis and reducing systemic estrogen levels.

3.
Cureus ; 15(9): e44969, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37822444

RESUMO

The intricate interplay between viral infections and non-alcoholic fatty liver disease (NAFLD) presents a fascinating and clinically significant intersection of virology and hepatology. This review article delves into the complex relationship between hepatitis B virus (HBV), hepatitis A virus (HAV), hepatitis E virus (HEV), and NAFLD. It outlines the shared mechanisms linking viral infections to NAFLD development, including their effects on lipid metabolism, immune responses, inflammation, and gut microbiota. The clinical implications of this interplay are explored, including challenges in diagnosis and management and potential therapeutic strategies. The review emphasises the need for a comprehensive understanding of these interactions as they impact disease progression, risk stratification, and treatment decisions. Furthermore, it highlights the importance of integrated approaches and personalised treatment paradigms for optimising patient care. As we navigate this intricate crossroads, the insights gained can reshape our understanding of liver health and contribute to more effective strategies for managing viral infections and NAFLD.

4.
Pan Afr Med J ; 45: 101, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719052

RESUMO

Chondroblastoma considered a rare form of osseous neoplasm contributes less than 1% of all bone tumours. It is typically found in young patients with chief complaints of moderate pain with joint stiffness. It develops as a lytic lesion in the epiphysis of long bones which might spread to the metaphysis. We report a case of an 18-year-old patient who presented with progressive right knee pain which aggravated with movements. Investigations included X-ray, magnetic resonance imaging (MRI), and biochemical assessment. A focal, well-defined, lesion in the upper end of the tibia with surrounding marrow oedema was observed and diagnostic arthroscopy was taken for management. Histopathology of specimen observed chondroblasts proliferation with areas of mature cartilage, and giant cells confirming intrasynovial chondroblastoma. Usually, surgery is the treatment of choice; however, possibilities of the secondary bone cyst, haemosiderin deposition on the joint, etc., make treatment approaches uncertain. Diagnostic arthroscopy is a rare but essential modality in such cases due to better visuals, complete tumour excision, and combination with adjuvant therapies. Chondroblastoma, if untreated, proves detrimental, hence, a thorough evaluation is critical for overall better outcomes.


Assuntos
Condroblastoma , Humanos , Adolescente , Condroblastoma/diagnóstico , Condroblastoma/cirurgia , Tíbia , Artroscopia , Biópsia , Dor
5.
Cureus ; 15(7): e41817, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37575864

RESUMO

Miliary tuberculosis (TB) is characterized by the spreading of Mycobacterium tuberculosis throughout the body, leading to various clinical manifestations and potential complications. This case involves a 58-year-old male who presented with fever, night sweats, weight loss, and respiratory symptoms. Diagnostic workup revealed the characteristic radiological findings of diffuse miliary nodules on CT scan and X-ray of the chest. Laboratory investigations, including a positive interferon-gamma release assay, supported the diagnosis. The patient was initiated on a multidrug anti-TB regimen consisting of rifampicin, isoniazid, pyrazinamide, and ethambutol, with adjunctive corticosteroids for severe manifestations. Close monitoring and supportive care were provided. The patient started anti-TB therapy and his health improved significantly. He was able to receive a kidney transplant successfully. The case report emphasizes the importance of early recognition, timely diagnosis, and appropriate treatment initiation to improve patient outcomes.

6.
Cureus ; 15(5): e38928, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37313086

RESUMO

Post-implantation syndrome (PIS) is a frequent complication after aortic dissection repair surgery, posing significant risks to patient recovery and survival. We present a case report of a 62-year-old male who underwent aortic dissection repair surgery and developed PIS. The patient exhibited symptoms of fever, pain, and inflammation at the surgery site, along with increased levels of inflammatory markers. He was managed with a combination of anti-inflammatory medications, pain management, and antibiotics, which gradually improved symptoms over weeks. Our case highlights the importance of recognizing the potential for PIS in patients undergoing aortic dissection repair surgery and employing timely interventions to manage this condition.

7.
Cureus ; 15(4): e37835, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37223161

RESUMO

A glioependymal cyst (GEC) is a rare type of cyst that occurs within the brain and spinal cord. A 42-year-old male patient with a cystic lesion in the right frontal lobe was admitted to the hospital to have his headache, vertigo, and body spasms evaluated. MRI scans showed a mass in the right side of the frontal lobe which caused a mass effect over the lateral ventricle and corpus callosum. The patient became symptom-free after the craniotomy, followed by fenestration of cortices and cyst wall removal.

8.
Cureus ; 15(4): e37808, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37214064

RESUMO

McKusick-Kaufman syndrome is a rare genetic disorder that affects limb development, genital formation, and heart function. It is caused by mutations in the MKKS gene on chromosome 20. Individuals with this condition may have extra fingers or toes, fused labia or undescended testes, and, less commonly, severe heart defects. Diagnosis involves a physical examination and genetic testing, while treatment focuses on symptom management, including surgical intervention if necessary. The prognosis varies depending on the severity of associated complications. In a recent case, a 27-year-old woman with fetal hydrometrocolpos gave birth to a female neonate with extra digits on both hands and feet, fused labia, and a small vaginal opening. The neonate also had a large abdominal cystic mass, and echocardiography revealed a patent foramen ovale. Genetic testing confirmed an MKKS gene mutation, and the hydrometrocolpos required surgical management. Early diagnosis and intervention can improve outcomes for individuals with this syndrome.

9.
ACS Appl Mater Interfaces ; 15(17): 21562-21574, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37083352

RESUMO

The kinetics and morphology of the ordering of block copolymer (BCP) films are highly dependent on the processing pathway, as the enthalpic and entropic forces driving the ordering processes can be quite different depending on process history. We may gain some understanding and control of this variability of BCP morphology with processing history through a consideration of the free energy landscape of the BCP material and a consideration of how the processing procedure moves the system through this energy landscape in a way that avoids having the system becoming trapped into well-defined metastable minima having a higher free energy than the target low free energy ordered structure. It is well known that standard thermal annealing (TA) of BCPs leads to structures corresponding to a well-defined stable free energy minimum; however, the BCP must be annealed for a very long time before the target low free energy structures can be achieved. Herein, we show that the same target low-energy structure can be achieved relatively quickly by subjecting as-cast films to an initial solvent annealing [direct immersion annealing (DIA) or solvent vapor annealing (SVA)] procedure, followed by a short period of TA. This process relies on lowering the activation energy barrier by reducing the glass-transition temperature through DIA (or SVA), followed by a multi-interface chain rearrangement through sequential TA. This energy landscape approach to ordering should be applicable to the process design for ordering many other complex materials.

10.
Cureus ; 15(2): e34558, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36879696

RESUMO

Hypertension is one of the most notorious non-communicable diseases the medical fraternity is dealing with in this decade. A wide array of medications have been included in the treatment regimen, one of which is calcium channel blockers. Amlodipine is commonly administered from this class. The reports of adverse drug reactions to the intake of amlodipine are very scarce to date. Association of gingival hyperplasia with the administration of this drug is rare and is what we have reported in this case. The theory that is being put forward for this adverse reaction is that the gingival fibroblasts are induced via the proliferative signaling pathways in association with the formation of bacterial plaques. Several classes of drugs other than calcium channel blockers are known to cause this reaction. Anti-epileptics along with anti-psychotic drugs are comparatively more prevalent. Thorough scaling and root planing are used to identify and treat amlodipine-induced gingival hypertrophy. The cause of gingival expansion is unknown, and there is currently no cure other than surgically removing the enlarged tissue and maintaining better dental hygiene. Immediate stoppage of the causative drug is advised in these cases along with the surgical remodeling of the affected gingiva.

11.
Natl Med J India ; 36(3): 145-149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38692607

RESUMO

Background Ayurveda, the Indian system of medicine, has been practised in India since ages. We evaluated the overall awareness regarding Ayurveda among patients attending two specialty clinics at a tertiary care institute. Methods We did a cross-sectional study on patients attending the cardiology and neurology clinics at a tertiary care hospital in India. We conducted this paper-based survey using a standardized, validated questionnaire. Statistical analysis was performed using STATA version 14.2. Results Three hundred and ninety-seven patients agreed to participate in the study. Their mean (SD) age was 45.65 (15.02) years. Among them 68.5% were men and 56.9% were from urban areas. Participants perceived that Ayurveda comprised herbal drugs (77.6%), metallic/herbo-mineral preparations (44.3%), Panchakarma therapy (22.2%) and personalized medicine (37.8%). Principal sources of information were TV promotional programmes (34.7%) and newspaper advertisements (13.9%). Nearly two-thirds (63%) of participants opined that Ayurveda is effective in chronic disorders. Although only 9.1% of participants reported the use of Ayurvedic medicines, 89.2% believed it would be beneficial if the All India Institute of Medical Sciences (AIIMS), New Delhi had Ayurveda services. Three-fourths (75.8%) of respondents were interested to participate in research studies integrating Ayurveda with modern medicine. Conclusion Imprecise knowledge and awareness towards Ayurveda appears to prevail in addition to the low practice among the patients surveyed. We found imprecise knowledge of Ayurvedic therapies and its low usage among patients attending specialized OPDs in a tertiary care hospital. The major source of information reported was promotional advertisements in the print and electronic media. Our survey shows a need for awareness programmes for general public at various levels.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Ayurveda , Humanos , Ayurveda/estatística & dados numéricos , Masculino , Feminino , Índia , Pessoa de Meia-Idade , Estudos Transversais , Adulto , Centros de Atenção Terciária/estatística & dados numéricos , Inquéritos e Questionários , Neurologia/estatística & dados numéricos , Cardiologia/estatística & dados numéricos , Idoso
12.
Cureus ; 14(10): e29814, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36337796

RESUMO

From conception to childbirth, there are many physical, hormonal, and psychological changes that a woman undergoes during pregnancy. During this time, balance is also affected, resulting in symptoms like vertigo and unsteadiness. These symptoms can lead to physical impairment and disability and can develop at any time. Vertigo in pregnancy has not been extensively written about. The subject of a narrative review is vertigo in pregnant patients. In pregnant women, hormonal alterations in the peripheral tissues and inner ear organs may contribute to vertigo. Meniere's disease, mild convulsive positional dizziness, and oculomotor migraines are all commonly exacerbated by pregnancy. Between the second and third trimesters of pregnancy, specific modifications to proprioception and hearing are also detected during physical examination. Patients who are pregnant typically experience these symptoms throughout this time. Some vertigo conditions can worsen during pregnancy, while others can appear at any time. Understanding audio-vestibular symptoms' pathological and clinical relationship during pregnancy requires more study.

13.
J Family Med Prim Care ; 11(6): 2503-2506, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36119209

RESUMO

Background: Scrub typhus is a reemerging zoonosis, which presents as acute febrile illness. Very few paediatric prospective studies on this disease are reported from Eastern India. This prospective observational study was carried out to study the clinical presentation, diagnosis, complications and immediate outcome of Scrub typhus in paediatric population in a tertiary care hospital from Eastern India. Material and Methods: Totally 209 cases between 1 month and 18 years of age were included. Clinical manifestations, laboratory parameters and immediate outcome of all patients were recorded. All the data were collected and plotted in Microsoft Excel master chart. Continuous data were presented as mean ± standard deviation (SD) and categorical data as frequency and percentage. All the data analysis was performed using statistical software IBM Statistical Package for the Social Sciences (SPSS) version 20.0. Results: Highest number of cases (41.1%) were found between 1 year and 5 years age group. Fever was the presenting complaint in all cases. Other common symptoms were cough (34%), pain abdomen (23.4%), vomiting (23%), seizure (11.5%) and altered sensorium (9.6%). Hepatomegaly was found in 56.5% and splenomegaly in 39.7% cases. Eschar was found in 27.3% cases. C-reactive protein was elevated (>10 mg/L) in 93.3% children. Other complications were pneumonitis (20.6%), meningoencephalitis (12.4%), septic shock (8.6%), acute respiratory distress syndrome (5.7%), myocarditis (4.8%) and acute kidney injury (4.3%). Mortality was low (1%). Conclusion: Scrub typhus is not uncommon in paediatric population and it must be considered as a close differential diagnosis of any acute febrile illness even when classical clinical presentations are not found. Early treatment results in favourable outcome.

14.
Proc Natl Acad Sci U S A ; 119(32): e2203483119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35925890

RESUMO

Many biopolymers are highly charged, and as in the case of many polymer mixtures, they tend to phase separate as a natural consequence of chain connectivity and an associated relatively low entropy of polymer mixing. Recently, it has become appreciated that the phase-separated structures formed by such polyelectrolyte blends, called "complex coacervates," underlie numerous biological structures and processes essential to living systems, and there has been intense interest in understanding the unique physical features of this type of phase-separation process. In the present work, we are particularly concerned with the field responsiveness of stabilized coacervate droplets formed after the phase separation of polyelectrolyte blend solution and then exposed to deionized water, making the droplet interfacial layer acquire a viscoelastic character that strongly stabilizes it against coalescence. We show that we can precisely control the positions of individual droplets and arrays of them with relatively low-voltage electric fields (on the order of 10 V/cm) and that the imposition of an oscillatory field gives rise to chain formation with coarsening of these chains into long fibers. Such a phase-separation-like process is generally observed in electrorheological fluids of solid colloidal particles subjected to much larger field strengths. The key to these coacervates' electrorheological properties is the altered interfacial viscoelastic properties when the droplets are introduced into deionized water and the associated high polarizability of the droplets, similar to the properties of many living cells. Since many different molecular payloads can be incorporated into these stable droplets, we anticipate many applications.

16.
ACS Appl Mater Interfaces ; 14(10): 12824-12835, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35245016

RESUMO

The template-free unidirectional alignment of lamellar block copolymers (l-BCPs) for sub-10 nm high-resolution patterning and hybrid multicomponent nanostructures is important for technological applications. We demonstrate a modified soft-shear-directed self-assembly (SDSA) approach for aligning pristine l-BCPs and l-BCPs with incorporated polymer-grafted nanoparticles (PGNPs), as well as the l-BCP conversion to aligned gold nanowires, and hybrid of metallic gold nanowire and dielectric silica nanoparticle in the form of line-dot nanostructures. The smallest patterns have a half-pitch as small as 9.8 nm. In all cases, soft-shear is achieved using a high-molecular-mass polymer topcoat layer, with support on a neutral bottom layer. We also show that the hybrid line-dot nanostructures have a red-shifted plasmonic response in comparison to neat gold nanowires. These template-free aligned BCPs and nanowires have potential use in nanopatterning applications, and the line-dot nanostructures should be useful in the sensing of biomolecules and other molecular species based on the plasmonic response of the nanowires.

17.
Langmuir ; 37(5): 1823-1837, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33502208

RESUMO

With an aim to understand the interaction mechanism of bovine serum albumin (BSA) with copper nanoclusters (CuNCs), three different types CuNCs having chemically different surface ligands, namely, tannic acid (TA), chitosan, and cysteine (Cys), have been fabricated, and investigations are carried out in the absence and presence of protein (BSA) at ensemble-averaged and single-molecule levels. The CuNCs, capped with different surface ligands, are consciously chosen so that the role of surface ligands in the overall protein-NCs interactions is clearly understood, but, more importantly, to find whether these CuNCs can interact with protein in a new pathway without forming the "protein corona", which otherwise has been observed in relatively larger nanoparticles when they are exposed to biological fluids. Analysis of the data obtained from fluorescence, ζ-potential, and ITC measurements has clearly indicated that the BSA protein in the presence of CuNCs does not attain the binding stoichiometry (BSA/CuNCs > 1) that is required for the formation of "protein corona". This conclusion is further substantiated by the outcome of the fluorescence correlation spectroscopy (FCS) study. Further analysis of data and thermodynamic calculations have revealed that the surface ligands of the CuNCs play an important role in the protein-NCs binding events, and they can alter the mode and thermodynamics of the process. Specifically, the data have demonstrated that the binding of BSA with TA-CuNCs and Chitosan-CuNCs follows two types of binding modes; however, the same with Cys-CuNCs goes through only one type of binding mode. Circular dichroism (CD) measurements have indicated that the basic structure of BSA remains almost unaltered in the presence of CuNCs. The outcome of the present study is expected to encourage and enable better application of NCs in biological applications.


Assuntos
Coroa de Proteína , Soroalbumina Bovina , Dicroísmo Circular , Cobre , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Termodinâmica
18.
Appl Opt ; 59(22): G107-G111, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749322

RESUMO

We demonstrate feedback cooling of a millimeter-scale, 40 kHz SiN membrane from room temperature to 5 mK (3000 phonons) using a Michelson interferometer, and discuss the challenges to ground-state cooling without an optical cavity. This advance appears within reach of current membrane technology, positioning it as a compelling alternative to levitated systems for quantum sensing and fundamental weak force measurements.

19.
PLoS Genet ; 16(5): e1008773, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32469896

RESUMO

Principal component analysis (PCA) is a key tool for understanding population structure and controlling for population stratification in genome-wide association studies (GWAS). With the advent of large-scale datasets of genetic variation, there is a need for methods that can compute principal components (PCs) with scalable computational and memory requirements. We present ProPCA, a highly scalable method based on a probabilistic generative model, which computes the top PCs on genetic variation data efficiently. We applied ProPCA to compute the top five PCs on genotype data from the UK Biobank, consisting of 488,363 individuals and 146,671 SNPs, in about thirty minutes. To illustrate the utility of computing PCs in large samples, we leveraged the population structure inferred by ProPCA within White British individuals in the UK Biobank to identify several novel genome-wide signals of recent putative selection including missense mutations in RPGRIP1L and TLR4.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Biologia Computacional/métodos , Mutação de Sentido Incorreto , Receptor 4 Toll-Like/genética , População Branca/genética , Algoritmos , Bancos de Espécimes Biológicos , Genética Populacional , Estudo de Associação Genômica Ampla/métodos , Humanos , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal , Reino Unido/etnologia
20.
Adv Biomed Res ; 9: 75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33912491

RESUMO

Extrapulmonary tuberculosis (TB) is a well-recognized cause of pyrexia of unknown origin. However, clinical presentation of TB in children with isolated hematological abnormalities is extremely rare. Anemia, usually normocytic, normochromic, leukopenia, leukocytosis, thrombocytopenia, thrombocytosis, and monocytosis are more common complications of TB rather than pancytopenia. Only anecdotal case reports and small case series are available in this regard. We are reporting an 18-year-old boy who presented with on and off low-grade fever for 3 months and anorexia and progressive pallor for 1 month. After extensive workup, pancytopenia remained unexplained. Bone marrow (BM) examination revealed caseating granulomas, along with Mantoux positivity and contact with sputum-positive pulmonary TB. He responded favorably to antitubercular therapy (ATT) within 2 months. This report alerts clinicians to be vigilant regarding the rare possibility of BM TB while investigating unexplained pancytopenia, as it is completely reversible with ATT.

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