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1.
J Cell Biochem ; : e30644, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39286999

RESUMO

Breast cancer is the major cause of cancer-related mortality and frequent malignancies among women worldwide. The TRIM (Tripartite Motif) protein family is a broad and diverse set of proteins that contain a conserved structural motif known as the tripartite motif, which comprises of three different domains, B-box domain, Coiled-coil domain and RBR (Ring-finger, B-box, and coiled-coil) domain. TRIM proteins are involved in regulating cancer growth and metastasis. However, TRIM proteins are still unexplored in cancer cell regulation. In this study, by using a cancer database expression of all TRIM proteins was determined in breast cancer. Out of 77 TRIM genes, 16 genes were upregulated in breast cancer. Here, the upregulated TRIM26 gene's role is not yet explored in breast cancer. Indeed, TRIM26 is upregulated in 21 cancer types out of 33 cancer types. To investigate the role of TRIM26 in breast cancer, siRNA-mediated gene silencing was carried out in MCF-7 and MDA-MB 231 breast cancer cells. Reduced expression of TRIM 26 decreased cancer cell proliferation, migration and invasion with simultaneous reduction of various proliferative, cell cycle and mesenchymal markers and upregulation of epithelial markers. Further, docking studies found potential novel plant metabolites. Thus, targeting TRIM26 may provide a novel therapeutic approach for breast cancer treatment.

2.
Chemistry ; : e202402425, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297522

RESUMO

Herein, we report the synthesis of a Mn(II)-based coordination polymer (CP); and its structure, phase consistency and thermal stability have been established by single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD) and thermalgravimetric analysis (TGA) respectively. This is the first example of paramgnetic Mn(II)-based CP that acts as pH-dependent emitting material [lem= 525 nm (pH = 2.0-4.0) and 450 nm (pH = 5.0-12.0)]. Its emission is quenched by Pd2+ in aqueous medium in presence of other thirteen cations with reasonably low pH-dependent limits of detection (LODs) [21.178 ppb (pH= 3), 15.005 ppb (pH = 7.0) and 59.940 ppb (pH = 10.0)] as described by well-established mechanism. Therefore, urgency of such stable sensor remains high in regard to the environmental pollution.

3.
Angew Chem Int Ed Engl ; : e202413605, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297731

RESUMO

Fluorescent foams with interconnected pores are attractive for the detection and quantification of various products. However, many fluorescent probes are suffering from aggregation-caused fluorescence quenching in their solid/aggregated state, are costly, and/or not straightforward to incorporate in foams, limiting their utility for this application. Herein, non-isocyanate polyurethane foams, prepared by the simple water-induced self-blowing process, present a nonconventional fluorescence behaviour, i.e. they are intrinsically fluorescent with a multicolor emission without requiring ex-situ traditional fluorescent probes. These foams demonstrate utility for capturing-sensing gaseous formaldehyde (an emblematic indoor air pollutant), as well as for detecting and quantifying various metal ions (Fe2+, Cu2+, Fe3+, Hg2+). They are also able to selectively sense tetracycline antibiotic in a ratiometric way with a high sensitivity. By exploiting the unique multicolor photoluminescent foam properties, a smartphone-compatible device is used for the facile antibiotic quantification. This nonconventional fluorescence behaviour is discussed experimentally and theoretically, and is mainly based on clusteroluminescence originating from multiple hydrogen bonding and hetero-atomic sub-luminophores, thus from aggregation-induced emission luminogens that are naturally present in the foams. This work illustrates that easily accessible non-conventional fluorescent NIPU foams characterized by a modular emission wavelength have an enormous potential for multiple substrates detection and quantification.

4.
J Biochem Mol Toxicol ; 37(11): e23454, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37409753

RESUMO

In spite of recent advances made in understanding its progression, cancer is still a leading cause of death across the nations. Molecular pathophysiology of these cancer cells largely differs depending on cancer types and even within the same tumor. Pathological mineralization/calcification is seen in various tissues including breast, prostate, and lung cancer. Osteoblast-like cells derived after trans-differentiation of mesenchymal cells usually drive calcium deposition in various tissues. This study aims to explore the presence of osteoblast-like potential in lung cancer cells and its prevention. ALP assay, ALP staining, nodule formation, RT-PCR, RT-qPCR, and western blot analysis experiments were carried out in lung cancer A549 cells to achieve said objective. Expressions of various osteoblast markers (e.g., ALP, OPN, RUNX2, and Osterix) along with osteoinducer genes (BMP-2 and BMP-4) were observed in A549 cells. Moreover, ALP activity and ability leading to nodule formation revealed the presence of osteoblast-like potential in lung cancer cells. Here, BMP-2 treatment increased expressions of osteoblast transcription factors such as RUNX2 and Osterix, enhanced ALP activity, and augmented calcification in this cell line. It was also observed that antidiabetic metformin inhibited BMP-2 mediated increase in osteoblast-like potential and calcification in these cancer cells. The current study noted that metformin blocked BMP-2 mediated increase in epithelial to mesenchymal transition (EMT) in A549 cells. The above findings for the first time unravel that A549 cells possess osteoblast-like potential which drives lung cancer calcification. Metformin might prevent BMP-2 induced osteoblast-like phenotype of the lung cancer cells with concomitant inhibition of EMT to inhibit lung cancer tissue calcification.


Assuntos
Neoplasias Pulmonares , Metformina , Masculino , Humanos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Neoplasias Pulmonares/metabolismo , Transição Epitelial-Mesenquimal , Metformina/farmacologia , Células A549 , Diferenciação Celular , Osteoblastos/metabolismo , Osteogênese
5.
Indian J Crit Care Med ; 27(2): 139-146, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36865513

RESUMO

Background: To evaluate the role of ultrasound during initial fluid resuscitation along with clinical guidance in reducing the incidence of fluid overload on day 3 in children with septic shock. Materials and methods: It was a prospective, parallel limb open-labeled randomized controlled superiority trial done in the PICU of a government-aided tertiary care hospital in Eastern India. Patient enrolment took place between June 2021 and March 2022. Fifty-six children aged between 1 month and 12 years, with proven or suspected septic shock, were randomized to receive either ultrasound-guided or clinically guided fluid boluses (1:1 ratio) and subsequently followed up for various outcomes. The primary outcome was frequency of fluid overload on day 3 of admission. The treatment group received ultrasound-guided fluid boluses along with the clinical guidance and the control group received the same but without ultrasound guidance upto 60 mL/kg of fluid boluses. Results: The frequency of fluid overload on day 3 of admission was significantly lower in the ultrasound group (25% vs 62%, p = 0.012) as was the median (IQR) cumulative fluid balance percentage on day 3 [6.5 (3.3-10.3) vs 11.3 (5.4-17.5), p = 0.02]. The amount of fluid bolus administered was also significantly lower by ultrasound [median 40 (30-50) vs 50 (40-80) mL/kg, p = 0.003]. Resuscitation time was shorter in the ultrasound group (13.4 ± 5.6 vs 20.5 ± 8 h, p = 0.002). Conclusion: Ultrasound-guided fluid boluses were found to be significantly better than clinically guided therapy, in preventing fluid overload and its associated complications in children with septic shock. These factors make ultrasound a potentially useful tool for resuscitation of children with septic shock in the PICU. How to cite this article: Kaiser RS, Sarkar M, Raut SK, Mahapatra MK, Uz Zaman MA, Roy O, et al. A Study to Compare Ultrasound-guided and Clinically Guided Fluid Management in Children with Septic Shock. Indian J Crit Care Med 2023;27(2):139-146.

6.
Indian J Crit Care Med ; 26(3): 331-338, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35519909

RESUMO

Background: Acute respiratory distress syndrome (ARDS) associated with COVID-19 in children is not well described in the literature, so this study was designed to assess the severity, clinical course, different treatment measures, and outcome of this group of patients. Patients and methods: This descriptive study was performed by retrospective chart review of children admitted in pediatric intensive care unit (PICU) in the age-group of 1 month to 12 years over the period of 6 months (July-December 2020) in a tertiary care pediatric COVID facility in eastern India. Severity of ARDS, ventilator settings, oxygenation and laboratory parameters, and outcomes were documented. Predictors associated with severe ARDS were evaluated. Results: Among 128 laboratory-confirmed pediatric COVID-19 cases admitted in PICU, 18 (14%) developed ARDS, 6 (33.3%) had severe ARDS, and 3 (16.6%) succumbed to death. Outcome was measured by median hospital stay [20 days (IQR 19, 21)], PICU stay [13 days (IQR 10, 16)], and 28-day ventilator-free days [14 days (IQR 13, 22)]. Half (n = 9) of our study cohort had different comorbidities and congenital heart disease being the most common (4, 22.2%). Median positive end-expiratory pressure requirement was 10 cm H2O (9, 11) for invasively ventilated children (n = 13, 72.2%) along with peak inspiratory pressure of 24 cm H2O (20, 29) and mean airway pressure of 17 cm H2O (14, 20). Median oxygenation index was 13.3 (10.5, 18.6). Nine (69.2%) out of 13 intubated children had undergone prone ventilation. C-reactive protein (CRP) and D-dimer levels were significantly high in children with severe ARDS alongside pSOFA and lung USG score. Conclusion: Incidence of ARDS in pediatric COVID-19 though less but is not rare. Elevated CRP, D-dimer values, and high lung USG scores were associated with severe ARDS. Those who died had significant comorbidity. How to cite this article: Sarkar M, Das B, Mahapatra MK, Roychowdhoury S, Das S, Konar MC. A Retrospective Analysis of Clinical Manifestations, Management and Outcome of Acute Respiratory Distress Syndrome Associated with Coronavirus Disease-2019 Infection in Children. Indian J Crit Care Med 2022;26(3):331-338.

7.
Macromol Rapid Commun ; 42(2): e2000522, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33210389

RESUMO

This work reports the design and synthesis of two nonaromatic biocompatible macromolecular luminogens, i.e., 2-(dimethylamino)ethyl methacrylate-co-2-(dimethylamino)ethyl 3-(N-(methylol)acrylamido)-2-methylpropanoate-co-N-(methylol)acrylamide/DMAEMA-co-DMAENMAMP-co-NMA (P1) and methacrylic acid-co-3-(N-(methylol)acrylamido)-2-methylpropanoic acid-co-N-(methylol)acrylamide/MEA-co-NMAMPA-co-NMA (P2), prepared through in situ anchored acrylamido-ester/DMAENMAMP and acrylamido-acid/NMAMPA third comonomers, respectively, in a facile polymerization of two non-luminous monomers in water medium to circumvent the drawbacks related to aggregation-caused quenching of aromatic luminogens. The structures of P1/P2, in situ anchored comonomers, fluorophores, N-branching associated n-π* interactions, and hydrogen bonding assisted aggregation-enhanced emissions are comprehended by nuclear magnetic resonance, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible, thermogravimetric analysis (TGA), dynamic light scattering (DLS), transmission electron microscopy (TEM), fluorescence lifetime, and fluorescence imaging. P1 and P2 are appropriate for sensitive detections/exclusions of Fe(III)/Cu(II) and cell-imaging. The intrinsic fluorescence, on-off sensing, selective coordinations of Fe(III) and Cu(II) with fluorophores, emission quenching mechanisms, and removals of Fe(III) and Cu(II) are investigated by DFT/NTO analyses of P1/P2 and Fe(III)-P1 and Cu(II)-P2 complexes, XPS, and isotherms and kinetics parameters. The excellent biocompatibilities, comparable limit of detections, i.e., 1.70 × 10-7 and 1.59 × 10-7 [m], and higher adsorption capacities, i.e., 77.25 and 154.13 mg g-1 , at low ppm; 303 K; and pH = 7 compel P1/P2 to be acceptable for multipurpose applications.


Assuntos
Compostos Férricos , Adsorção , Substâncias Macromoleculares , Espectroscopia Fotoeletrônica , Polimerização
8.
Chemistry ; 26(2): 502-516, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31599070

RESUMO

To circumvent costly fluorescent labeling, five nonconventional, multifunctional, intrinsically fluorescent aliphatic terpolymers (1-5) have been synthesized by C-C/C-N-coupled, solution polymerization of two non-emissive monomers with protrusions of fluorophore monomers generated in situ. These scalable terpolymers were suitable for sensing and high-performance exclusion of CuII , logic function, and bioimaging. The structures of the terpolymers, in situ attachment of fluorescent monomers, aggregation-induced enhanced emission, bioimaging ability, and super adsorption were investigated by 1 H and 13 C NMR, EPR, FTIR, X-ray photoelectron, UV/Vis, and atomic absorption spectroscopy, thermogravimetric analysis, high-resolution transmission electron microscopy, dynamic light scattering, solid-state fluorescence, fluorescence imaging, and fluorescence lifetime measurements, as well as by isotherm, kinetics, and thermodynamic studies. The geometries and electronic structures of the fluorophores and the absorption and emission properties of the terpolymers were examined by DFT, time-dependent DFT, and natural transition orbital analyses. For 1, 2, and 5, the limits of detection were determined to be 1.03×10-7 , 1.65×10-7 , and 1.77×10-7 m, respectively, and the maximum adsorption capacities are 1575.21, 1433.70, and 1472.21 mg g-1 , respectively.

9.
Langmuir ; 36(22): 6178-6187, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32418427

RESUMO

Biocompatible, nonconventional, multifunctional, purely aliphatic, light-emitting terpolymers, i.e., acrylonitrile-co-3-(N-isopropylacrylamido)propanenitrile-co-N-isopropylacrylamide (AN-co-NIPAMPN-co-NIPA, 1) and acrylonitrile-co-3-(N-hydroxymethylacrylamido)propanenitrile-co-N-hydroxymethylacrylamide (AN-co-NHMAMPN-co-NHMA, 2), were designed and synthesized via N-H-functionalized C-C + N-C-coupled in situ protrusions/grafting of fluorophore monomers, i.e., NIPAMPN and NHMAMPN, by solution polymerization of two highly hydrophobic nonemissive monomers in water. These scalable and reusable 1 and 2 were suitable for high-performance three-in-one applications, such as Fe(III) sensors, imaging of Madin-Darby canine kidney (MDCK) and human lung cancer (A549) cells, and security inks. The structures of 1 and 2, N-C-coupled in situ attachments/grafting of third fluorophore monomers, grafting events, and aggregation-enhanced emissions (AEEs), were analyzed by 1H and 13C NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, thermogravimetric (TG) analysis, high-resolution transmission electron microscopy (HRTEM), dynamic light scattering (DLS), fluorescence imaging, and fluorescence lifetime. The geometries, electronic structures, and absorption/emission properties of 1 and 2 at optimized compositions were examined by density functional theory (DFT), time-dependent DFT (TDDFT), and natural transition orbital (NTO) analyses. The limits of detection were 3.20 × 10-7 and 1.37 × 10-7 M for 1 and 2, respectively. The excellent biocompatibility of 1 and 2 was confirmed by >95% retention of MDCK and A549 cell morphologies.

10.
Neurol India ; 65(4): 801-803, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28681755

RESUMO

Early infantile epileptic encephalopathy has a grave outcome. Dravet syndrome (DS), characterized by early onset, refractory seizures, and intellectual deficit is one of the variants of the condition. SCN1B gene mutation is one of the lesser known variants of DS. Increased awareness of genetic analysis has increased the early diagnosis of DS for an early prognostication as well as genetic counselling of parents. We present the case of a 7-month old male child who started having recurrent febrile, and thereafter, afebrile seizures, following administration of a vaccination at 3 months. He developed global developmental delay, and is presently on multiple anticonvulsants. Genetic analysis was suggestive of SCN1B gene mutation associated with DS.


Assuntos
Epilepsias Mioclônicas/genética , Subunidade beta-1 do Canal de Sódio Disparado por Voltagem/genética , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Deficiências do Desenvolvimento/etiologia , Epilepsias Mioclônicas/diagnóstico por imagem , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Mutação/genética , Prognóstico , Convulsões Febris/etiologia , Estado Epiléptico/etiologia
11.
J Pediatr Intensive Care ; 12(4): 256-263, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37970143

RESUMO

This study aimed to assess different clinical, disease severity, laboratory, treatment, and outcome-related factors of COVID-19 positive infants admitted to a pediatric intensive care unit (PICU) and to compare these parameters with COVID-19 positive noninfants (1-12 years of age) who also required intensive care admission. This retrospective observational study was conducted in a PICU of a tertiary care, dedicated pediatric COVID facility. The clinical, epidemiological, laboratory parameters, and treatment outcomes of COVID-19 infected infants admitted to the PICU were recorded and analyzed. During comparison with the noninfant group, malignancy and coinfection with dengue and scrub typhus were excluded from both groups. A total 313 COVID-19 positive children aged from 1 month to 12 years old were admitted, of which 115 (36.7%) children required PICU admission. Infants constituted 37.4% of total PICU admissions. Most common symptoms were respiratory (83.7%) followed by fever (60.5%). Fifteen (34.9%) infants presented with shock. Ten infants (23.3%) had myocardial dysfunction. C-reactive protein (CRP) and ferritin were high in 60.5 and 16.7% infants, respectively. Fourteen infants needed invasive mechanical ventilation. Nine patients had acute respiratory distress syndrome (ARDS) and five had MIS-C. However, 53.5% infants had different comorbidities. Four infants died and all of them had severe comorbidities. Respiratory distress ( p = 0.009), pediatric sequential organ failure assessment score ( p = 0.032) and number of ARDS cases ( p = 0.044) were significantly higher in infants than noninfants. Infants are one of the most vulnerable groups of children suffering from serious illness from COVID-19 infection requiring PICU admission due to predominantly respiratory involvement. Overall outcome was good among infants without significant comorbidity.

12.
Materials (Basel) ; 16(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37512434

RESUMO

The present study investigates the effects of multiple passes of equal channel angular pressing (ECAP) on magnesium alloy sheets with the assistance of an Inconel plunger along with a die setup having a channel angle of 120° and corner angle of 10° operating at a temperature of 200 °C followed by the required heat treatment processes. The microstructural analysis of the sheet samples at various stages of the multi-pass hot ECAP has shown evidence of ultrafine grain refinement (UFG) due to the occurrence of severe plastic deformation. X-ray diffraction analysis has also exhibited the presence of phases like MgZn and CeZn3 which is supposedly responsible for the enhancement of the mechanical properties. As a result, the room temperature tensile and compressive strengths have improved by 6.12% and 6.63%, respectively, after the second pass, and 11.56% and 15.64%, respectively, after the fourth pass of ECAP. Additionally, the hardness of the sheets has increased by 6.49% and 16.64% after the second and fourth pass of hot ECAP, respectively, mainly attributed to the drastic decrease in grain size from 164 µm to 12 µm within four ECAP passes, all these with a negligible change in ductility. This success in the thermomechanical processing of Mg-RZ5 alloy sheets using a die channel angle of 120° with a minimal number of passes of hot ECAP under a controlled equivalent strain, further opens doors for incorporating optimizations and/or additional aspects so as to achieve even better grain refinements, and consequently, mechanical strength improvements thereby catering to the industrial needs of aerospace and construction areas.

13.
Indian Pediatr ; 59(7): 531-534, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35596647

RESUMO

OBJECTIVE: To evaluate pulmonary functions in children with transfusion-dependent thalassemia, and its reversal (lung dysfunction) using intensive intravenous chelation with desferrioxamine (DFO) (4 weeks). METHODS: This descriptive study enrolled 77 children with transfusion-dependent thalassemia. Pulmonary function test (PFT) and iron load (serum ferritin (SF) and T2* MRI of heart and liver) were done. PFT included spirometry, total lung capacity (TLC) by helium dilution test and diffusion capacity by carbon monoxide (DLCO). Follow-up PFT was available for 13 children with moderate to severe lung dysfunction given intravenous DFO. RESULTS: 50 (68.8%) patients had lung dysfunction, most commonly diffusional impairment (48; 96%), and reduced TLC (11; 22%); and none had obstructive pattern. 9 (81.8%) patients with restrictive defect had moderate to severely deranged DLCO. PFT and T2* MRI values were inversely correlated with serum ferritin. Among 13 patients receiving intensive chelation for 4 weeks, significant improvement was noticed in forced expiratory volume in one minute/ forced vital capacity ratio (DFEV1/FVC) (P=0.009), DDLCO (P=0.006) and DSF (P=0.01). CONCLUSIONS: Pulmonary dysfunction is common in children with multi-transfused thalassemia, and routine screening by PFT needs to be part of the management guidelines.


Assuntos
COVID-19 , Talassemia , Talassemia beta , COVID-19/epidemiologia , Criança , Ferritinas , Humanos , Pulmão/diagnóstico por imagem , Pandemias , SARS-CoV-2
14.
Clin Exp Pediatr ; 65(7): 358-366, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35577343

RESUMO

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, lung ultrasonography (US) has been gaining importance in pediatric intensive care and emergency settings for the screening, diagnosis, and monitoring of pulmonary pathology. PURPOSE: To describe the pattern of lung US changes in patients with COVID-19 pneumonia and its potential role in monitoring ventilated patients. METHODS: This prospective observational study included children aged 1 month to 12 years with a confirmed diagnosis of COVID-19. Lung US was performed using a high-frequency linear probe (5-12 MHz) in all children with moderate/severe respiratory symptoms within 24 hours of admission and then daily until the patient required oxygen therapy. Lung involvement severity was assessed using lung US scores, while lung aeration improvement or deterioration was measured using lung ultrasound reaeration scores (LUSReS). RESULTS: Of 85 children with moderate to severe disease, 54 with pulmonary disease were included. Of them, 50 (92.5%) had an interstitial pattern, followed by pleural line abnormalities in 44 (81.5%), reduced or absent lung sliding in 31 (57.4%), and consolidation in 28 (51.8%). A significantly higher lung US score (median, 18; interquartile range [IQR], 11-22) was observed in ventilated versus nonventilated patients (median, 9; IQR, 6-11). LUSReS improvement after positive end-expiratory pressure titration was positively correlated with improved dynamic lung compliance and oxygenation indices and negatively correlated with the requirement for driving pressure. Successful weaning could be predicted with 100% specificity if loss of LUSReS ≤ 5. CONCLUSION: Interstitial syndrome, fragmented pleural line, and subpleural microconsolidation were the most prevalent lung US findings in children with COVID-19 pneumonia. Thus, lung US may have the ability to monitor changes in lung aeration caused by mechanical ventilation and predict its successful weaning in children with COVID-19.

15.
Materials (Basel) ; 15(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36295161

RESUMO

Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas metal arc welded (GMAW) based WAAM process provides a higher deposition rate than other methods, making it suitable for additive manufacturing. The fabrication of mild steel (G3Si1), austenitic stainless steel (SS304), and a bimetallic sample of both materials were completed successfully using the GMAW based WAAM process. The microstructure characterization of the developed sample was conducted using optical and scanning electron microscopes. The interface reveals two discrete zones of mild steel and SS304 deposits without any weld defects. The hardness profile indicates a drastic increase in hardness near the interface, which is attributed to chromium migration from the SS304. The toughness of the sample was tested based on the Charpy Impact (ASTM D6110) test. The test reveals isotropy in both directions. The tensile strength of samples deposited by the WAAM technique measured slightly higher than the standard values of weld filament. The deep hole drilling (DHD) method was used to measure the residual stresses, and it was determined that the stresses are compressive in the mild steel portion and tensile in austenitic stainless steel portion, and that they vary throughout the thickness due to variation in the cooling rate at the inner and outer surfaces.

16.
J Pediatr (Rio J) ; 98(5): 504-512, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35139344

RESUMO

OBJECTIVE: To describe the clinical characteristics, laboratory parameters, treatment, and predictors of an unfavorable outcome of critically ill children with SARS-CoV-2 infection. METHOD: This was a prospective observational study performed in a pediatric intensive care unit (PICU) of a tertiary care COVID referral hospital among critically ill children in the age group 1 month - 12 years admitted due to SARS-CoV-2 infection from June to December 2020. Demographic, clinical profile, pSOFA and PRISM III scores, laboratory parameters, treatment, and outcomes of the patients were recorded. Children who had a prolonged PICU stay (>14 days) or died were compared with those who were discharged from PICU within 14 days to assess predictors of unfavorable outcomes. RESULTS: PICU admission rate among hospitalized SARS-CoV-2 infected children was 22.1% (92/416). Infants comprised the majority of the ICU population. Invasive mechanical ventilation and inotropic support were required for 28.3% and 37% of patients, respectively. Remdesivir, IVIg, and steroids were administered to 15.2%, 26.1%, and 54.3% of the subjects, respectively. The mortality rate was 7.6 %. MIS-C patients were older, less comorbid, and required less ventilator support but more inotrope support than acute severe COVID-19 patients. Predictors of unfavorable outcomes were age < 1 year, fever duration > 5 days, respiratory distress, shock, comorbidity, elevated CRP (> 50 mg/L), procalcitonin (> 6 ng/L), D-dimer (> 6 µg/L) and arterial lactate (> 2 mmol/L). CONCLUSION: Critically ill children with unfavorable outcomes were predominantly infants, comorbid, prolonged fever, respiratory distress, shock and elevated inflammatory markers, D-dimer and lactate. These factors may be useful for watchful monitoring and early intervention.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , COVID-19/complicações , COVID-19/terapia , Criança , Estado Terminal/terapia , Humanos , Imunoglobulinas Intravenosas , Lactente , Unidades de Terapia Intensiva Pediátrica , Lactatos , Pró-Calcitonina , Estudos Retrospectivos , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica
17.
ACS Appl Bio Mater ; 5(6): 2990-3005, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35579235

RESUMO

Here, four nontraditional fluorescent polymers (NTFPs) of varying N,N-dimethyl-2-propenamide (DMPA) and butyl prop-2-enoate (BPE) mole ratios, i.e., 2:1 (NTFP1), 4:1 (NTFP2), 8:1 (NTFP3), and 16:1 (NTFP4), are prepared via random polymerization in water. The maximum fluorescence enhancement of NTFP3 makes it suitable for ratiometric pH sensing, Cu(II) sensing, and pH-dependent cell imaging of Madin-Darby canine kidney (MDCK) cells. The oxygen donor functionalities of NTFP3 involved in binding and sensing with Cu(II) ions are studied by absorption, emission, electron paramagnetic resonance, Fourier transform infrared (FTIR), and O1s/Cu2p X-ray photoelectron spectroscopies (XPS). The spectral responses of the ratiometric pH sensor within 1.5-11.5 confirm 22 and 44 nm red shifts in absorption and ratiometric emission, respectively. The striking color changes from blue (436 nm) to green (480 nm) via an increase in pH are thought to be the stabilization of the charged canonical form of tertiary amide, i.e., -C(O-)═N+(CH3)2, realized from the changes in the absorption/fluorescence spectra and XPS/FTIR analyses. The through-space n-π* interactions in the NTFP3 aggregate, N-branching-associated rigidity, and nonconventional intramolecular hydrogen bondings of adjacent NTFP3 moieties in the NTFP3 aggregate contribute to aggregation-enhanced emissions (AEEs). Here, structures of NTFP3, NTFP3 aggregate, and Cu(II)-NTFP3; absorption; n-π* interactions; hydrogen bondings; AEEs; and binding with Cu(II) are ascertained by density functional theory, time-dependent density functional theory, and reduced density gradient calculations. The excellent limits of detection and Stern-Volmer constants of NTFP3 are 2.24 nM/0.14234 ppb and 4.26 × 103 M-1 at pH = 6.5 and 0.95 nM/0.06037 ppb and 4.90 × 103 M-1 at pH = 8.0, respectively. Additionally, the Stokes shift and binding energy of NTFP3 are 13,636 cm-1/1.69 eV and -4.64 eV, respectively. The pH-dependent MDCK cell imaging ability of noncytotoxic NTFP3 is supported via fluorescence imaging and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.


Assuntos
Imagem Óptica , Polímeros , Animais , Cães , Hidrogênio , Concentração de Íons de Hidrogênio , Imagem Óptica/métodos , Polímeros/química , Espectrometria de Fluorescência
18.
ACS Appl Bio Mater ; 3(9): 6155-6166, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-35021748

RESUMO

Intrinsically fluorescent biocompatible multifunctional multipurpose terpolymers, i.e., methyl methacrylate-co-methyl 3-(N-isopropylacrylamido)-2-methylpropanoate-co-N-isopropylacrylamide (MMA-co-MNIPAMP-co-NIPAm, 1) and methyl methacrylate-co-methyl 3-(N-hydroxymethylacrylamido)-2-methylpropanoate-co-N-hydroxymethylacrylamide (MMA-co-MNHMAMP-co-NHMAm, 2), were synthesized via in situ-attached acrylamido-ester monomers during polymerization of hydrophobic monomers in water medium. These nonconjugated fluorescent terpolymers presenting aggregation-enhanced emissions (AEEs) were suitable for Bi(III) sensors, Bi(III) removal, cell imaging, and security inks. The fluorescence properties, mechanisms of quenching, interactions of Bi(III) with 1 and 2, and Bi(III) adsorption were explored using theoretical analyses of 1, 2, Bi(III)-1, and Bi(III)-2. Considering the overall properties, 1 was more suitable for diverse prospective applications.

19.
ACS Omega ; 5(7): 3333-3345, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32118148

RESUMO

The intrinsically fluorescent highly hydrophilic multifunctional aliphatic terpolymer, maleic acid (MA)-co-2-(N-(hydroxymethyl)acrylamido)succinic acid (NHASA)-co-N-(hydroxymethyl)acrylamide (NHMA), that is, 1, was designed and synthesized via C-C/N-C-coupled in situ allocation of a fluorophore monomer, that is, NHASA, composed of amido and carboxylic acid functionalities in the polymerization of two nonemissive MA and NHMA. The scalable and reusable intrinsically fluorescent biocompatible 1 was suitable for sensing and high-performance adsorptive exclusion of Fe(III), along with the imaging of Madin-Darby canine kidney cells. The structure of 1, in situ fluorophore monomer, aggregation-induced enhanced emission, cell-imaging ability, and superadsorption mechanism were studied via microstructural analyses using 1H/13C NMR, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectroscopy, ultraviolet-visible spectroscopy, thermogravimetric analysis, dynamic light scattering, high-resolution transmission electron microscopy, solid-state fluorescence, fluorescence lifetime, and fluorescence imaging, along with measuring kinetics, isotherms, and thermodynamic parameters. The location, electronic structures, and geometries of the fluorophore and absorption and emission properties of 1 were investigated using density functional theory and natural transition orbital analyses. The limit of detection and the maximum adsorption capacity were 2.45 × 10-7 M and 542.81 mg g-1, respectively.

20.
ACS Biomater Sci Eng ; 6(3): 1397-1407, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33455376

RESUMO

The nonconventional purely aliphatic intrinsically fluorescent multifunctional terpolymers, such as 2-acrylamido-2-methylpropane sulfonic acid-co-2-(3-acrylamidopropylamido)-2-methylpropane sulfonic acid-co-acrylamide (AMPS-co-APMPS-co-AM, 1), acrylic acid-co-3-acrylamidopropanoic acid-co-acrylamide (AA-co-APA-co-AM, 2), and methacrylic acid-co-3-acrylamido-2-methyl propanoic acid-co-acrylamide (MAA-co-AMPA-co-AM, 3), were synthesized via N-H functionalized multi-C-C/N-C coupled in situ attachments of fluorophore monomers, that is, APMPS, APA, and AMPA, in solution polymerization of two non-fluorescent monomers. These terpolymers were suitable for selective Cr(III) sensors, high-performance exclusions of Cr(III), and fluorescence imaging of human osteosarcoma cancer cells. The structures of 1, 2, and 3, in situ attachments of fluorescent amino acid monomers, locations of fluorophores, aggregation-induced enhanced emissions, and the superadsorption mechanism were understood via microstructural analyses. The geometries, electronic structures, and the low-lying singlet-singlet absorption and emission of 1, 2, and 3 were explored using density functional theory (DFT), time-dependent DFT, and natural transition orbital analyses. The ionic and variable interactions of 1, 2, and 3 with Cr(III) were envisaged via analyses of adsorbed microstructures, fitting of kinetics data to a pseudo-second-order model, and the measurements of activation energies. For 1/2/3, limit of detection values and adsorption capacities were 1.88 × 10-7/3.75 × 10-7/1.25 × 10-7 M and 1316.35/1431.40/1372.18 mg g-1, respectively, at pHi = 7.0, 303 K, and 1000 ppm. The better overall properties made 3 to be more suitable in sensing and cell imaging.


Assuntos
Corantes , Polímeros , Adsorção , Humanos , Substâncias Macromoleculares , Polimerização
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