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3.
BMJ Case Rep ; 17(8)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39106993

RESUMEN

Cutaneous involvement is an uncommonly encountered manifestation in multiple myeloma (MM), more commonly observed in patients with aggressive subtypes, and often resistant to conventional therapies. Due to its infrequency, reported clinical characteristics have been diverse and relatively non-specific. Particularly uncommon is lower extremity involvement. In this case report, we present a unique case of a patient with refractory immunoglobulin G lambda MM, who subsequently developed recurrence in the lower leg, while being on systemic therapy. Initially, the lesion resembled squamous cell carcinoma, posing a diagnostic challenge. Through meticulous histopathological and immunohistochemical evaluation, cutaneous involvement by MM was confirmed. This case highlights the importance of maintaining a high clinical suspicion for cutaneous involvement in patients with MM who present with new skin lesions, as early diagnosis is crucial for appropriate management.


Asunto(s)
Mieloma Múltiple , Neoplasias Cutáneas , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/complicaciones , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Masculino , Recurrencia Local de Neoplasia , Diagnóstico Diferencial , Persona de Mediana Edad , Anciano
4.
Molecules ; 29(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39202917

RESUMEN

Lignocellulose is a major biopolymer in plant biomass with a complex structure and composition. It consists of a significant amount of high molecular aromatic compounds, particularly vanillin, syringeal, ferulic acid, and muconic acid, that could be converted into intracellular metabolites such as polyhydroxyalkanoates (PHA) and hydroxybutyrate (PHB), a key component of bioplastic production. Several pre-treatment methods were utilized to release monosaccharides, which are the precursors of the relevant pathway. The consolidated bioprocessing of lignocellulose-capable microbes for biomass depolymerization was discussed in this study. Carbon can be stored in a variety of forms, including PHAs, PHBs, wax esters, and triacylglycerides. From a biotechnology standpoint, these compounds are quite adaptable due to their precursors' utilization of hydrogen energy. This study lays the groundwork for the idea of lignocellulose valorization into value-added products through several significant dominant pathways.


Asunto(s)
Lignina , Lignina/química , Lignina/metabolismo , Biomasa , Alimentos , Polihidroxialcanoatos/química , Polihidroxialcanoatos/biosíntesis , Polihidroxialcanoatos/metabolismo , Residuos , Biopolímeros/química , Biopolímeros/metabolismo , Alimento Perdido y Desperdiciado
5.
ACS Appl Mater Interfaces ; 16(28): 36953-36961, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38976781

RESUMEN

Metal-organic frameworks (MOFs) are favorable hosting materials for fixing enzymes to construct enzyme@MOF composites and to expand the applications of biocatalysts. However, the rigid structure of MOFs without tunable hollow voids and a confinement effect often limits their catalytic activities. Taking advantage of the smart soft polymers to overcome the limitation, herein, a protection protocol to encapsulate the enzyme in zeolitic imidazolate framework-8 (ZIF-8) was developed using a glutathione-sensitive liposome (L) as a soft template. Glucose oxidase (GOx) and horseradish peroxidase (HRP) were first anchored on a light- and thermoresponsive porous poly(styrene-maleic anhydride-N,N-dimethylaminoethyl methacrylate-spiropyran) membrane (PSMDSP) to produce PSMDSP@GOx-HRP, which could provide a confinement effect by switching the UV irradiation or varying the temperature. Afterward, embedding PSMDSP@GOx-HRP in L and encapsulating PSMDSP@GOx-HRP@L into hollow ZIF-8 (HZIF-8) to form PSMDSP@GOx-HRP@HZIF-8 composites were performed, which proceeded during the crystallization of the framework following the removal of L by adding glutathione. Impressively, the biocatalytic activity of the composites was 4.45-fold higher than that of the free enzyme under UV irradiation at 47 °C, which could benefit from the confinement effect of PSMDSP and the conformational freedom of the enzyme in HZIF-8. The proposed composites contributed to the protection of the enzyme against harsh conditions and exhibited superior stability. Furthermore, a colorimetric assay based on the composites for the detection of serum glucose was established with a linearity range of 0.05-5.0 mM, and the calculated LOD value was 0.001 mM in a cascade reaction system. This work provides a universal design idea and a versatile technique to immobilize enzymes on soft polymer membranes that can be encapsulated in porous rigid MOF-hosts. It also holds potential for the development of smart polymer@enzyme@HMOFs biocatalysts with a tunable confinement effect and high catalytic performance.


Asunto(s)
Biocatálisis , Enzimas Inmovilizadas , Glucosa Oxidasa , Peroxidasa de Rábano Silvestre , Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Peroxidasa de Rábano Silvestre/química , Peroxidasa de Rábano Silvestre/metabolismo , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Temperatura , Polímeros/química , Zeolitas/química , Luz , Liposomas/química
6.
Phys Chem Chem Phys ; 26(31): 20971-20983, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39046419

RESUMEN

Insufficient proton conductivity and oxidative stability of sulfonated hydrocarbons hinder their applicability as proton exchange membrane electrolytes in fuel cells. In this regard, fabrication of proton conducting mixed-matrix membranes (PC-MMMs) can be a superior approach to obtain desirable properties. In this work, a triazole ligand (1H-1,2,4 triazole) was coordinated to a zinc metal node to create a 3D metal-organic framework (MOF) and incorporated as an additive in a sulfonated poly(ether ether ketone) matrix at 1, 3, and 5 weight percentage to fabricate PC-MMMs by the casting process. Several characterization tools such as electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterise these membranes and study their potential application as electrolyte(s) in PEMFCs (proton exchange membrane fuel cells). Membranes were also tested for water uptake, ion-exchange capacity and oxidative stability in Fenton's reagent. The performance of the polymeric composite membrane containing a 3 wt% MOF was then assessed in a H2/O2 single cell as it demonstrated the highest proton conductivity of 0.04 S cm-1 among all the compositions and a maximum current density of 1191 mA cm-2. The membrane was also subjected to an OCV hold test for 12 hours to study the chemical durability over a period of time. This report establishes that the inclusion of a triazole based MOF enhances the proton conductivity, performance, and thermal and chemical durability of composite membranes which can be considered as a promising electrolyte material at intermediate temperatures after a proper optimisation of different cell parameters.

7.
Anal Bioanal Chem ; 416(20): 4571-4580, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38902347

RESUMEN

Recently, open tubular capillary electrochromatography (OT-CEC) has captured considerable interest; its efficient separation capability hinges on the interactions between analytes and polymer coatings. However, in situ growth of stimuli-responsive polymers as coatings has been rarely studied and is crucial for expanding the OT-CEC technique and its application. Herein, following poly(styrene-maleicanhydride) (PSM) chemically bonded onto the inner surface of the capillary, a dual pH/temperature stimuli-responsive block copolymer, P(SMN-COOH), was prepared by in situ polymerizing poly(N-isopropylacrylamide) carboxylic acid terminated [P(N-COOH)] in PSM. An OT-CEC protocol was first explored using the coated capillary for epimedins separation. As a proof of concept, the developed OT-CEC system facilitated hydrogen bonding and tuning the hydrophilic/hydrophobic interactions between the test analytes and the P(SMN-COOH) coating by varying buffer pH and environmental temperature. Four epimedins with similar chemical structures were baseline separated under 40 °C at pH 10.0, exhibiting dramatical improvement in separation efficiency in comparison to its performance under 25 °C at pH 4.0. In addition, the coated capillary showed good repeatability and reusability with relative standard deviations for migration time and peak area between 0.7 and 1.7% and between 2.9 and 4.6%, respectively, and no significant changes after six runs. This work introduces a paradigm for efficient OT-CEC separation of herbal medicines through adjusting the interactions between analytes and smart polymer coatings, addressing polymer coating design and OT-CEC challenges.

9.
Heliyon ; 10(10): e30989, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38813199

RESUMEN

This article investigates the concept of dominant metric dimensions in zero divisor graphs (ZD-graphs) associated with rings. Consider a finite commutative ring with unity, denoted as R, where nonzero elements x and y are identified as zero divisors if their product results in zero (x.y=0). The set of zero divisors in ring R is referred to as L(R). To analyze various algebraic properties of R, a graph known as the zero-divisor graph is constructed using L(R). This manuscript establishes specific general bounds for the dominant metric dimension (Ddim) concerning the ZD-graph of R. To achieve this objective, we examine the zero divisor graphs for specific rings, such as the ring of Gaussian integers modulo m, denoted as Zm[i], the ring of integers modulo n, denoted as Zn, and some quotient polynomial rings. Our research unveils new insights into the structural similarities and differences among commutative rings sharing identical metric dimensions and dominant metric dimensions. Additionally, we present a general result outlining bounds for the dominant metric dimension expressed in terms of the maximum degree, girth, clique number, and diameter of the associated ZD-graphs. Through this exploration, we aim to provide a comprehensive framework for analyzing commutative rings and their associated zero divisor graphs, thereby advancing both theoretical knowledge and practical applications in diverse domains.

10.
ACS Nano ; 18(18): 11978-11987, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38652759

RESUMEN

The interplay between strong Coulomb interactions and kinetic energy leads to intricate many-body competing ground states owing to quantum fluctuations in 2D electron and hole gases. However, the simultaneous observation of quantum critical phenomena in both electron and hole regimes remains elusive. Here, we utilize anisotropic black phosphorus (BP) to show density-driven metal-insulator transition with a critical conductance ∼e2/h which highlights the significant role of quantum fluctuations in both hole and electron regimes. We observe a T-linear resistivity from the deep metallic phase to the metal-insulator boundary at moderate temperatures, while it turns to Fermi liquid behavior in the deep metallic phase at low temperatures in both regimes. An analysis of the resistivity suggests that disorder-dominated transport leads to T-linear behavior in the hole regime, while in the electron regime, the T-linear resistivity results from strong Coulomb interactions, suggestive of strange-metal behavior. Successful scaling collapse of the resistivity in the T-linear region demonstrates the link between quantum criticality and the T-linear resistivity in both regimes. Our study provides compelling evidence that ambipolar BP could serve as an exciting testbed for investigating exotic states and quantum critical phenomena in hole and electron regimes of 2D semiconductors.

11.
J Pharm Bioallied Sci ; 16(Suppl 1): S753-S756, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38595546

RESUMEN

Objective: The present study aimed to conduct an assessment of parents' knowledge, attitudes, and practices toward methamphetamine "shabu" abuse among youth and its risk factors. Materials and Methods: The present cross-sectional descriptive study was conducted on a sample of 1179 parents. Parents were assured that questionnaire content would stay classified and was given anonymously. It had 20 demographic, drug use, and addiction treatment questions. Statistical Package for Social Sciences v. 24 and Chi-Square test were used to examine the data after evaluating and coding it. Results: Out of a total of 1179 participants, only 11% had not heard about shabu, about 38% did not know the main symptoms of crystal addiction, and 46% did not know the long side effects of crystal addiction. The majority of participants mentioned that shabu is available in powder format (57%) or liquid (13%), while 27% did not know its form. Most of the participants (97%) think that the drug of shabu or crystal or ice is dangerous; about 60% of participants mentioned that there is an addict in the family. Conclusion: Parents have good knowledge levels regarding different aspects of methamphetamine or shabu abuse, symptoms, and its risk factors. Further in-depth studies are needed at whole Saudi Arabia.

12.
J Mater Chem B ; 12(16): 3996-4003, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38563677

RESUMEN

Encapsulation of enzymes within porous materials has shown great promise for protecting enzymes from denaturation, increasing their tolerance to harsh environments and promoting their industrialization. However, controlling the conformational freedom of the encapsulated enzymes to enhance their catalytic performance remains a great challenge. To address this issue, herein, following immobilization of GOx and HRP on a thermo-responsive porous poly(styrene-maleic-anhydride-N-isopropylacrylamide) (PSMN) membrane, a GOx-HRP@PSMN@HZIF-8 composite was fabricated by encapsulating GOx-HRP@PSMN in hollow ZIF-8 (HZIF-8) with liposome (L) as the sacrificial template. The improved conformational freedom for enzymes arising from the hollow cavity formed in ZIF-8 through the removal of L enhanced the mass transfer and dramatically promoted the catalytic activity of the composite. Interestingly, at high temperature, the coiled PN moiety in PSMN provided the confinement effect for GOx-HRP, which also significantly boosted the catalytic performance of the composites. Compared to the maximum catalytic reaction rates (Vmax) of GOx-HRP@PSMN@LZIF-8, the free enzyme and GOx-HRP@ZIF-8, the Vmax of the GOx-HRP@PSMN@HZIF-8 composite exhibited an impressive 17.8-fold, 10.8-fold and 6.0-fold enhancement at 37 °C, respectively. The proposed composites successfully demonstrated their potential as catalytic platforms for the colorimetric detection of glucose in a cascade reaction. This study paves a new way for overcoming the current limitations of immobilizing enzymes in porous materials and the use of smart polymers for the potential fabrication of enzyme@polymer@MOF composites with tunable conformational freedom and confinement effect.


Asunto(s)
Enzimas Inmovilizadas , Glucosa Oxidasa , Estructuras Metalorgánicas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Estructuras Metalorgánicas/química , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Peroxidasa de Rábano Silvestre/química , Peroxidasa de Rábano Silvestre/metabolismo , Polímeros/química , Propiedades de Superficie , Porosidad , Tamaño de la Partícula , Catálisis , Biocatálisis , Poliestirenos/química
13.
Heliyon ; 10(3): e25471, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38322963

RESUMEN

In traditional statistics, all research endeavors revolve around utilizing precise, crisp data for the predictive estimation of population mean in survey sampling, when the supplementary information is accessible. However, these types of estimates often suffer from bias. The major aim is to uncover the most accurate estimates for the unknown value of the population mean while minimizing the mean square error (MSE). We have employed the neutrosophic approach, which is the extension of classical statistics that deals with the uncertain, vague, and indeterminate information, and proposed a neutrosophic predictive estimator of finite population mean using the kernel regression. The proposed estimator does not yield a single numerical value but instead provides an interval range within which the population parameter is likely to exist. This approach enhances the efficiency of the estimators by offering an estimated interval that encompasses the unknown value of the population mean with the least possible mean squared error (MSE). The simulation-based efficiency of the proposed estimator is discussed using the Sine, Bump and real-time temperature data set of Islamabad by using symmetric (Gaussian) kernel. The proposed non-parametric neutrosophic estimator has shown more effective results under the various bandwidth selectors than the adapted neutrosophic estimators.

14.
Pak J Med Sci ; 40(1Part-I): 20-25, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38196467

RESUMEN

Objective: The current study was designed to explore the relationship of TIMI and SYNTAX risk score to predict the CAD extent and severity in STEMI patients. Methods: For this cross-sectional study, 304 STEMI patients undergoing PPCI were enrolled at Department of Interventional Cardiology NICVD Karachi from September 2021 to January 2022. and the TIMI risk score was determined at enrolment. Based on these scorings, the patients were grouped as low, intermediate, and high risk, i.e., a score of ≤ 3, 4 to 7, and ≥ 8, respectively. The SYNTAX scores were utilized to assess the extent of CAD. Results: Statistically significant difference was found in symptoms to balloon time (p=0.001), history of diabetes (p=0.006), angina (p=0.011), obesity (p=0.048), STEMI type (p=0.003), Killip classes (p=0.000), Infarct-Related Artery (p=0.006), number of diseased vessels (p<0.01), LMS > 50% (p=0.000), PCI type (p<0.01), collateral circulation (p<0.01), In-hospital mortality (p<0.01), LV support (p<0.01), and post-procedural TIMI flow (p=0.013), among the three TIMI risk groups. Significant correlation was found among TIMI risk score and SYNTAX score. Conclusion: It is observed that the TIMI risk scores are highly correlated with the SYNTAX Score in predicting the CAD severity in STEMI patients.

15.
Small ; 20(23): e2310946, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38229536

RESUMEN

Owing to their extraordinary photophysical properties, organometal halide perovskites are emerging as a new material class for X-ray detection. However, the existence of toxic lead makes their commercialization questionable and should readily be replaced. Accordingly, several lead alternatives have been introduced into the framework of conventional perovskites, resulting in various new perovskite dimensionalities. Among these, Pb-free lower dimensional perovskites (LPVKs) not only show promising X-ray detecting properties due to their higher ionic migration energy, wider and tunable energy bandgap, smaller dark currents, and structural versatility but also exhibit extended environmental stability. Herein, first, the structural organization of the PVKs (including LPVKs) is summarized. In the context of X-ray detectors (XDs), the outstanding properties of the LPVKs and active layer synthesis routes are elaborated afterward. Subsequently, their applications in direct XDs are extensively discussed and the device performance, in terms of the synthesis method, device architecture, active layer size, figure of merits, and device stability are tabulated. Finally, the review is concluded with an in-depth outlook, thoroughly exploring the present challenges to LPVKs XDs, proposing innovative solutions, and future directions. This review provides valuable insights into optimizing non-toxic Pb-free perovskite XDs, paving the way for future advancements in the field.

16.
Chem Rec ; 24(1): e202300247, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37933973

RESUMEN

The high-temperature solid oxide fuel cells (SOFCs) are the most efficient and green conversion technology for electricity generation from hydrogen-based fuel as compared to conventional thermal power plants. Many efforts have been made to reduce the high operating temperature (>800 °C) to intermediate/low operating temperature (400 °C

17.
J Chromatogr A ; 1714: 464595, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38141483

RESUMEN

Fabricating polymeric coatings that are responsive to multiple/dual stimuli is crucial and remains a major challenge in the development of highly efficient open tubular capillary electrochromatography (OT-CEC). In this study, a pH and temperature-responsive block copolymer, poly(styrene-maleic anhydride 2-dimethylamino ethyl methacrylate), P(St-MAn-DMAEMA), was designed and synthesized. Using P(St-MAn-DMAEMA) as the coating, an OT-CEC protocol was constructed for the analysis of chromones. The morphology and hydrophobicity-hydrophilicity of the polymeric coating could change via varying the environmental conditions, affecting the separation efficiency of OT-CEC. Interestingly, the best performance of OT-CEC was achieved at pH 9.7 and 45 °C via tuning the interactions between the coating and the analytes. Additionally, the proposed OT-CEC method exhibited a good linear range for the detection of the three test chromones from 10.0 to 100.0 µM, with all correlation coefficients (R2) >0.997. The coatings also had good stability and reusability. This work provides an approach for the preparation of new multiple-stimuli-responsive polymeric coatings for the establishment of OT-CEC systems.


Asunto(s)
Electrocromatografía Capilar , Polímeros , Humanos , Polímeros/química , Electrocromatografía Capilar/métodos , Metacrilatos
18.
Mol Biotechnol ; 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37839042

RESUMEN

The economic exploration of renewable energy resources has hot fundamentals among the countries besides dwindling energy resources and increasing public pressure. Cellulose accumulation is a major bio-natural resource from agricultural waste. Cellulases are the most potential enzymes that systematically degrade cellulosic biomass into monomers which could be further processed into several efficient value-added products via chemical and biological reactions including useful biomaterial for human benefits. This could lower the environmental risks problems followed by an energy crisis. Cellulases are mainly synthesized by special fungal genotypes. The strain Trichoderma orientalis could highly express cellulases and was regarded as an ideal strain for further research, as the genetic tools have found compatibility for cellulose breakdown by producing effective cellulose-degrading enzymes. This strain has found a cellulase production of about 35 g/L that needs further studies for advancement. The enzyme activity of strain Trichoderma orientalis needed to be further improved from a molecular level which is one of the important methods. Considering synthetic biological approaches to unveil the genetic tools will boost the knowledge about commercial cellulases bioproduction. Several genetic transformation methods were significantly cited in this study. The transformation approaches that are currently researchers are exploring is transcription regulatory factors that are deeply explained in this study, that are considered essential regulators of gene expression.

19.
Micromachines (Basel) ; 14(9)2023 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-37763840

RESUMEN

Multilayer piezocomposite transducers are widely used in many applications where broad bandwidth is required for tracking and detection purposes. However, it is difficult to operate these multilayer transducers efficiently under frequencies of 100 kHz. Therefore, this work presents the modeling and optimization of a five-layer piezocomposite transducer with ten variables of nonuniform layer thicknesses and different volume fractions by exploiting the strength of the genetic algorithm (GA) with a one-dimensional model (ODM). The ODM executes matrix manipulation by resolving wave equations and produces mechanical output in the form of pressure and electrical impedance. The product of gain and bandwidth is the required function to be maximized in this multi-objective and multivariate optimization problem, which is a challenging task having ten variables. Converting it into the minimization problem, the reciprocal of the gain-bandwidth product is considered. The total thickness is adjusted to keep the central frequency at approximately 50-60 kHz. Piezocomposite transducers with three active materials, PZT5h, PZT4d, PMN-PT, and CY1301 polymer, as passive materials were designed, simulated, and statistically evaluated. The results show significant improvement in gain bandwidth compared to previous existing techniques.

20.
BMJ Case Rep ; 16(6)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37399348

RESUMEN

A patient in her early 20s presented with blood-stained sputum and shortness of breath. Initially, she was treated for pneumonia. Later, upon exacerbation of symptoms, further investigations were done which exhibited a left atrial mass causing compression of contralateral atrium. She underwent surgical resection of the mass, which was initially mistaken as myxoma. However, histopathological correlation revealed spindle cell sarcoma with focal myogenic differentiation. This case report highlights the role of Radiation Therapy in adjuvant setting with promising impact on improving local control after R2 resection. Cardiac spindle cell sarcoma, being one of the rarest cardiac tumours reported to date, warrants establishment of a Rare Tumour Multidisciplinary Team for management of such malignancies.


Asunto(s)
Neoplasias Cardíacas , Mixoma , Sarcoma , Femenino , Humanos , Sarcoma/radioterapia , Sarcoma/cirugía , Sarcoma/diagnóstico , Atrios Cardíacos/patología , Neoplasias Cardíacas/radioterapia , Neoplasias Cardíacas/cirugía , Neoplasias Cardíacas/diagnóstico , Mixoma/diagnóstico
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