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1.
J Am Chem Soc ; 146(30): 20937-20944, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-38979882

RESUMEN

Amidst burgeoning interest, atomically precise copper nanoclusters (Cu NCs) have emerged as a remarkable class of nanomaterials distinguished by their unparalleled reactivity. Nonetheless, the synthesis of hydride-free Cu NCs and their role as stable catalysts remain infrequently explored. Here, we introduce a facile synthetic approach to fabricate a hydride-free [Cu7(SC5H9)7(PPh3)3] (Cu7) NC and delineate its photophysical properties intertwined with their structural configuration. Moreover, the utilization of its photophysical properties in a photoinduced C-C coupling reaction demonstrates remarkable specificity toward cross-coupling products with high yields. The combined experimental and theoretical investigation reveals a nonradical mechanistic pathway distinct from its counterparts, offering promising prospects for designing hydride-free Cu NC catalysts in the future and unveiling the selectivity of the hydride-free [Cu7(SC5H9)7(PPh3)3] NC in photoinduced Sonogashira C-C coupling through a polar reaction pathway.

2.
Small ; 20(20): e2307666, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38279566

RESUMEN

Discovery of new topology covalent organic frameworks (COFs) is a mainstay in reticular chemistry and materials research because it not only serves as a stepwise guide to the designed construction of covalent-organic architectures but also helps to comprehend function from structural design point-of-view. Proceeding on this track, the first 3D COF, TUS-38, with the topology is constructed by reticulating a planar triangular 3-c node of D3h symmetry with a tetragonal prism 8-c node of D2h symmetry via [3 + 8] reversible imine condensation reaction. TUS-38 represents a twofold interpenetrated multidirectional pore network with a high degree of crystallinity and structural integrity. Interestingly, stemming from the nitrogen-rich s-triazine rings with electron-deficient character and ─C â• N─ linkages composing the TUS-38 framework that benefit to the charge-transfer and hence dipole-dipole electrostatic interactions between the framework and iodine in addition to exclusive topological characteristics of the exotic the net, TUS-38 achieves an exemplary capacity for iodine vapor uptake reaching 6.3 g g-1. Recyclability studies evidence that TUS-38 can be reused at least five times retaining 95% of its initial adsorption capacity; while density functional theory (DFT) calculations have heightened the understanding of the interactions between iodine molecules and the framework.

3.
J Environ Manage ; 354: 120261, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38354608

RESUMEN

The future of reactive nitrogen (N) for subtropical lowland rice to be characterised under diverse N-management to develop adequate sustainable practices. It is a challenge to increase the efficiency of N use in lowland rice, as N can be lost in various ways, e.g., through nitrous oxide (N2O) or dinitrogen (N2) emissions, ammonia (NH3) volatilization and nitrate (NO3-) leaching. A field study was carried out in the subsequent wet (2021) and dry (2022) seasons to assess the impacts of different N management strategies on yield, N use efficiency and different N losses in a double-cropped rice system. Seven different N-management practices including application of chemical fertilisers, liquid organic fertiliser, nitrification inhibitors, organic nutrient management and integrated nutrient management (INM) were studied. The application of soil test-based neem-coated urea (NCU) during the wet season resulted in the highest economic yield, while integrated nutrient management showed the highest economic yield during the dry season. Total N losses by volatilization of NH3, N2O loss and leaching were 0.06-4.73, 0.32-2.14 and 0.25-1.93 kg ha-1, corresponding to 0.06-5.84%, 0.11-2.20% and 0.09-1.81% of total applied N, respectively. The total N-uptake in grain and straw was highest in INM (87-89% over control) followed by the soil test-based NCU (77-82% over control). In comparison, recovery efficiency of N was maximum from application of NCU + dicyandiamide during both the seasons. The N footprint of paddy rice ranged 0.46-2.01 kg N-eq. t-1 during both seasons under various N management. Ammonia volatilization was the process responsible for the largest N loss, followed by N2O emissions, and NO3- leaching in these subtropical lowland rice fields. After ranking the different N management practices on a scale of 1-7, soil test-based NCU was considered the best N management approach in the wet year 2021, while INM scored the best in the dry year 2022.


Asunto(s)
Oryza , Nitrógeno/análisis , Agricultura/métodos , Amoníaco/análisis , Suelo , Fertilizantes/análisis , Óxido Nitroso/análisis
4.
Nanoscale ; 16(20): 9642-9658, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38644768

RESUMEN

Silver Cluster-Assembled Materials (SCAMs) represent a new frontier of crystalline extended solids hallmarked by their customizable structures, commendable stabilities, and unique physical/chemical properties. Since their discovery in 2017, the diversity of organic linkers has endowed SCAMs with ingenious architectures and the application scenario has expanded beyond photoluminescence sensing to environmental sustainability and biomedical applications. It is critically important to chronicle these recent key advances and review the progress of SCAMs that can enable translating the material discoveries into real implementation. Herein, we provide a succinct overview of the trajectory of SCAM research, with crucial insights into atomic-level structural correlations with the phenomena at the nanoscale and discuss the gaps and opportunities that are still open in addition to charting a roadmap for future research directions.

5.
Asian Pac J Cancer Prev ; 25(6): 1911-1920, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38918651

RESUMEN

INTRODUCTION: Lung cancer is one of the commonest cause of cancer associated mortality worldwide. Platelets have emerged as key players in cancer development and progression by supporting tumor growth, and dissemination. In the present systematic review, we analyzed RNA transfer between cancer cells and platelets and explored potential role of different platelet RNA profiles as onco-signature in diagnosis, subtyping, disease progression and treatment monitoring in carcinoma lung carcinoma. MATERIALS AND METHODS: The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Cochrane Manual of Systematic Reviews and Meta-analysis that included seven studies on patients with lung cancer, with data on tumor-educated platelets, and control group. The outcome measured was based on sensitivity, specificity, and ROC. PUBMED, SCOPUS, Central Cochrane Registry of Controlled Trials and Science Direct databases were searched using specific search terms until October 2023. QUADAS - 2 tool was used to assess quality, risk of bias and applicability concerns. RESULTS: The analysis revealed AUC > 70% for different platelet mRNAs, with sensitivity and specificity of more than 60 %. AUC and sensitivity were highest for ITGA2B (AUC 0.922; sensitivity 92.8%). lncRNA GTF2H2-1 was the most specific platelet RNA. On QUADAS-2 tool, 3/7 articles were unclear in reference standards, patient flow timing, and 1/7 had high bias in both aspects. For applicability, 1/7 studies were unclear in reference standards, and 2/7 in index tests. CONCLUSION: TEP RNA can aid in early diagnosis of lung cancer and of proven utility in its early-stage detection. TEP RNA can also monitor disease progression and treatment response.


Asunto(s)
Biomarcadores de Tumor , Plaquetas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Biomarcadores de Tumor/sangre , Plaquetas/patología , Plaquetas/metabolismo , Pronóstico , ARN Largo no Codificante/genética , ARN Largo no Codificante/sangre
6.
J Biomed Opt ; 29(1): 017002, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38213472

RESUMEN

Significance: The photoacoustic (PA) technique, a noninvasive pump-probe technique, has found interesting applications in biomedical tissue diagnosis over the last decade. To take it a step further to clinical applications, the PA technique needs to be designed as an instrument focusing on a compact design, reducing the cost, and quickly providing a quantitative diagnosis. Aim: This work presents a design and characterization of a cost-effective, compact PA sensing instrument for biomedical tissue diagnosis. Approach: A compact laser diode case design is developed to house several laser diodes for PA excitation, and a pulsed current supply unit is also developed in-house to power the laser diodes to generate a 25 ns current pulse at a frequency of 20 kHz. After PA experimental data acquisition, the signal's frequency spectra were calculated to characterize the tissue quantitatively and correlated with their mechanobiological properties. Results: The corresponding dominant frequency peak in the PA spectral response (PASR) study was low in the fibrofatty normal breast tissue 0.26±0.03 MHz, compared to the dominant frequency peak of 1.60±0.016 MHz in the fibrocystic disease tissue, which had increased glandular and stromal elements, thereby increased tissue density. The histopathological findings correlated with the PASR results, and the fibrocystic breast disease tissue exhibited a higher dominant frequency peak and energy compared to the normal breast tissue. Conclusions: We experimented with an in vitro PASR study of fibrocystic human breast tissues and successfully differentiated different tissue types using quantitative spectral parameters peak frequency, mean frequency, and spectral energy. This gives the potential to take this technique further for cost-effective and quick clinical applications.


Asunto(s)
Láseres de Semiconductores , Técnicas Fotoacústicas , Humanos , Análisis Costo-Beneficio , Análisis Espectral , Técnicas Fotoacústicas/métodos
7.
J Neurosci Rural Pract ; 15(2): 182-193, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38746499

RESUMEN

Memory deficits are observed across psychiatric disorders ranging from the prodrome of psychosis to common mental disorders such as anxiety, depression, and dissociative disorders. Memory deficits among patients recovering from psychiatric disorders could be directly related to the primary illness or secondary to the adverse effect of a treatment such as Electroconvulsive Therapy (ECT). The trouble in the meaningful integration of working-memory and episodic memory is the most commonly affected domain that requires routine assessments. An update on the recent trends of methods of assessment of memory deficits is the first step towards understanding and correcting these deficits to target optimum recovery. A systematic literature search was conducted from October 2018 to October 2022 to review the recent methods of assessment of memory deficits in psychiatric disorders. The definition of 'Memory deficit' was operationalized as 'selective processes of memory, commonly required for activities of daily living, and affected among psychiatric disorders resulting in subjective distress and dysfunction'. We included 110 studies, most of them being conducted in western countries on patients with schizophrenia. Other disorders included dementia and mild cognitive impairment. Brief Assessment of Cognition in Schizophrenia, Cambridge Automated Neuropsychological Test Battery, California Verbal Learning Test, Trail Making Test Part A and B, Rey Auditory Verbal Learning Test, Wechsler Memory Scale, Wechsler Adults Intelligence Scale-IV were the most common neuropsychological assessments used. Mini-Mental State Examination and Montreal Cognitive Assessment were the most common bedside assessment tools used while Squire Subjective Memory Questionnaire was commonly used to measure ECT-related memory deficits. The review highlights the recent developments in the field of assessment of memory deficits in psychiatric disorders. Findings recommend and emphasize routine assessment of memory deficits among psychiatric disorders in developing countries especially severe mental illnesses. It remains interesting to see the role of standardized assessments in diagnostic systems given more than a decade of research on memory deficits in psychiatric disorders.

8.
J Cancer Res Ther ; 20(3): 935-942, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023601

RESUMEN

PURPOSE: Objective parameters for decision on adaptive radiotherapy depend on patient, tumor and treatment related factors. Present study reports geometric uncertainties occurring during high precision radiotherapy, beam fluence analysis and serial exit dose measurement as a patient-specific tool for adaptive radiotherapy. MATERIALS AND METHODS: Serial exit dose fluence of 24 patients (at baseline and mid-treatment) undergoing IMRT/VMAT treatment were measured. Baseline and midtreatment exit dose evaluation was done using gafchromic films in predefined region of interest. Difference of volume of GTV at baseline (from simulation CT scan) and midtreatment CBCT scan was calculated (ΔGTV). RESULTS: Population based systematic errors (mm) were 4.15, 2.26, 0.88 and random errors (mm) were 2.56, 3.69, and 2.03 in mediolateral (ML), craniocaudal (CC) and anteroposterior (AP) directions respectively. Gamma pass rate reduced with incremental shift. For a 5 mm shift, maximum deviation was found in anteroposterior axis (22.16 ± 7.50) and lowest in mediolateral axis (12.85 ± 4.95). On serial measurement of exit dose fluence, tumor shrinkage significantly influenced gamma pass rate. The mean gamma pass rate was significantly different between groups with 50% shrinkage of tumor volume (86.36 vs 96.24, P = 0.008, on multivariate analysis P = 0.026). CONCLUSION: Rapid fall of gamma pass rate was observed for set up error of ≥3 mm. Serial measurement of exit dose fluence by radiochromic film is a feasible method of exit dose comparison in IMRT/VMAT, where EPID dosimetry is not available with linear accelerator configuration. Our study suggests that there is a significant difference between gamma pass rates of baseline and mid treatment exit dose fluence with greater than 50% tumor shrinkage.


Asunto(s)
Fantasmas de Imagen , Garantía de la Calidad de Atención de Salud , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Estudios Prospectivos , Neoplasias/radioterapia , Neoplasias/patología , Carga Tumoral , Errores de Configuración en Radioterapia , Masculino , Tomografía Computarizada de Haz Cónico/métodos
9.
ACS Infect Dis ; 10(8): 2886-2898, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39079033

RESUMEN

Vibrio cholerae (V. cholerae), the etiological agent of cholera, employs various virulence factors to adapt and thrive within both aquatic and human host environments. Among these factors, the type VI secretion system (T6SS) stands out as one of the crucial determinants of its pathogenicity. Valine glycine repeat protein G1 (VgrG1) and hemolysin coregulated protein (HCP) are considered major effector molecules of T6SS. Previous studies have highlighted that VgrG1 interacts with HCP proteins. Additionally, it has been shown that VgrG1 possesses an actin cross-linking domain (ACD) with actin-binding activity. Interestingly, it was reported that purified HCP protein treatment increased the stress fibers within cells. Therefore, we hypothesize that HCP may interact with host cell actin, potentially playing a role in the cytoskeletal rearrangement during V. cholerae infection. To test this hypothesis, we characterized HCP from the V. cholerae O139 serotype and demonstrated its interaction with actin monomers. In silico analysis and experimental validation revealed the presence of an actin-binding site within HCP. Furthermore, overexpression of HCP resulted in its colocalization with actin stress fibers in host cells. Our findings establish HCP as an effector molecule for potent host cell actin cytoskeleton remodeling during V. cholerae infection, providing new insights into bacterial pathogenicity mechanisms. Understanding the interplay between bacterial effectors and host cell components is crucial for developing targeted therapeutic interventions against cholera and related infectious diseases.


Asunto(s)
Citoesqueleto de Actina , Proteínas Bacterianas , Vibrio cholerae , Vibrio cholerae/patogenicidad , Vibrio cholerae/metabolismo , Vibrio cholerae/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Humanos , Citoesqueleto de Actina/metabolismo , Interacciones Huésped-Patógeno , Unión Proteica , Factores de Virulencia/metabolismo , Factores de Virulencia/genética , Actinas/metabolismo , Cólera/microbiología , Proteínas Hemolisinas/metabolismo
10.
Noncoding RNA Res ; 9(4): 1333-1341, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39131689

RESUMEN

The disease burden of Oral Squamous Cell Carcinoma (OSCC) is rising day-by-day and is expected to rise 62 % through 2035. The chewing of tobacco, areca nut, and betel leaf, poor oral hygiene, and chronic infection are common risk factors of OSCC, but genetic and epigenetic factors also contribute equally. MicroRNAs (miRNAs) are comprised of small, non-coding endogenous RNA that regulate a plethora of biological activities by targeting messenger RNA through degradation or inhibition. Single Nucleotide Polymorphisms (SNPs) in miRNA genes can regulate the development and progression of OSCC. The present study aimed to determine the association between SNPs in miRNA genes (miRSNPs) with the risk of OSCC. A case-control study involving 225 histo-pathologically confirmed OSCC cases and 225 healthy controls was conducted, where 25 miRSNPs were analyzed by iPLEX MassArray analysis. A SNP rs12220909 in MIR4293 showed a highly protective effect (CC vs GG, OR = 0.0431, 95%CI = 0.005-0.323, p = 3e-6). Whereas three SNPs, namely, rs4705342 in MIR143 (CC vs TT, OR = 2.25, 95%CI = 2.00-2.53, p = 0.0008), rs531564 in MIR124 (CC vs GG, OR = 24.18, 95%CI = 3.22-181.37, p = 3e-6), and rs3746444 in MIR499 (AA vs GG, OR = 2.01, 95%CI = 1.32-3.05, p = 0.001) were significantly associated with a higher risk of OSCC. Additionally, NanoString-based nCounter miRNA expression profiling revealed that miR-499a (Log2FC = -1.07), and miR-143 (Log2FC = -1.56) were aberrantly expressed in OSCC tissue. Taken together, the above miSNPs may contribute to the high incidence of OSCC in central India. However, further studies with large cohorts and ethnic stratification are required to validate our findings.

11.
J Neurosci Rural Pract ; 15(1): 16-28, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476438

RESUMEN

Objectives: D-dimer levels are increased in stroke and cancer. Cancer patients are at a higher risk of stroke. However, the evidence is unclear if high D-dimer in stroke patients can suggest the diagnosis of concomitant cancer or the development of stroke in a cancer patient. The objective is to assess the evidence available on the baseline D-dimer level in stroke patients with and without cancer. Materials and Methods: We conducted the systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched PUBMED, Cochrane, ScienceDirect, and Scopus for potentially eligible articles published till June 2023. All the review steps were iterative and done independently by two reviewers. The Newcastle-Ottawa scale tool was used to assess the quality of included studies for case control and cohort studies and the Agency for Healthcare Research and Quality tool for cross-sectional studies. The qualitative synthesis is presented narratively, and quantitative synthesis is shown in the forest plot using the random effects model. I2 of more than 60% was considered as high heterogeneity. Results: The searches from all the databases yielded 495 articles. After the study selection process, six papers were found eligible for inclusion in the qualitative and quantitative synthesis. In the present systematic review, 2651 patients with ischemic infarcts are included of which 404 (13.97%) patients had active cancer while 2247 (86.02%) did not. The studies included were of high quality and low risk of bias. There were significantly higher baseline D-dimer levels in stroke patients with cancer than in non-cancer patients with a mean difference of 4.84 (3.07-6.60) P < 0.00001. Conclusion: D-dimer is a simple and relatively non-expensive biomarker that is increased to significant levels in stroke patients, who have cancer and therefore may be a tool to predict through screening for active or occult cancer in stroke patients.

12.
Discov Nano ; 19(1): 103, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884869

RESUMEN

Graphene-based nanomaterials (graphene, graphene oxide, reduced graphene oxide, graphene quantum dots, graphene-based nanocomposites, etc.) are emerging as an extremely important class of nanomaterials primarily because of their unique and advantageous physical, chemical, biological, and optoelectronic aspects. These features have resulted in uses across diverse areas of scientific research. Among all other applications, they are found to be particularly useful in designing highly sensitive biosensors. Numerous studies have established their efficacy in sensing pathogens and other biomolecules allowing for the rapid diagnosis of various diseases. Considering the growing importance and popularity of graphene-based materials for biosensing applications, this review aims to provide the readers with a summary of the recent progress in the concerned domain and highlights the challenges associated with the synthesis and application of these multifunctional materials.

13.
PLoS One ; 18(12): e0295679, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38128032

RESUMEN

This work focuses on the utilization of counter-propagating plane waves for optical manipulation, which provides a unique approach to control the behavior of Rayleigh and Dipolar nanoparticles immersed in a homogeneous or heterogeneous medium. Our study presents an interesting finding of a repulsive force between plasmonic-chiral heterodimers where the particles move away from each other in both near and far field regions. Interestingly, this repulsive thrust supports the wave like nature of light for the case of homogeneous background but particle type nature of light for heterogenous background. At first, we have investigated the theory underlying the optical trapping of the chiral particle and the impact of this phenomenon on the overall repulsive behavior of the heterodimers placed in air (homogeneous) background. After that, our proposed set-up has further been investigated putting in air-water interface (heterogenous background) and by varying light angle only a little bit. Our observation for this interface case is suggesting the transfer of Minkowski momentum of photon to each optically pulled Rayleigh or dipolar particle of the dimer set, which ultimately causes a broad-band giant repulsive thrust of the dimers. However, in absence of the other particle in the cluster, a single half-immersed particle does not experience the pulling force for the broad-band spectrum. The 'common' reason of the observed repulsive thrust of the dimers for both the aforementioned cases has been attributed to "modified" longitudinal Optical Binding Force (OBF). Technically, this work may open a new way to control the repulsion and attraction between the nanoparticles both in near and far field regions by utilizing the background and the counter-propagating waves. We also believe that this work manifests a possible simple set-up, which will support to observe a background dependent wave 'or' particle nature of light experimentally.


Asunto(s)
Nanopartículas , Pinzas Ópticas
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