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1.
Artigo em Inglês | MEDLINE | ID: mdl-38685466

RESUMO

OBJECTIVE: The study objective was to assess a machine learning model's ability to predict the occurrence of life-altering events in hemiarch surgery and determine contributing patient characteristics and intraoperative factors. METHODS: In total, 602 patients who underwent hemiarch replacement at a high-volume aortic center from 2009 to 2022 were included. Patients were randomly divided into training (80%) and testing (20%) sets with various eXtreme gradient boosting candidate models constructed to predict the risk of experiencing life-altering events, including stroke, mortality, or new renal replacement therapy requirement. A total of 64 input parameters from the index hospitalization were identified, including 24 demographic characteristics as well as 8 preoperative and 32 intraoperative variables. A SHapley Additive exPlanation beeswarm plot was generated to identify and interpret the impact of individual features on the predictions of the final model. RESULTS: A life-altering event was noted in 15% (90/602) of patients who underwent hemiarch replacement, including urgent/emergency cases and dissections. The final eXtreme Gradient Boosting model demonstrated a cross-validation accuracy of 88% on the testing set and was well calibrated as evidenced by a low Brier score of 0.12. The best performing model achieved an area under the receiver operating characteristic curve of 0.76 and an area under the precision recall curve of 0.55. The SHapley Additive exPlanation beeswarm plot provided insights into key features that significantly influenced model prediction. CONCLUSIONS: Machine learning demonstrated superior accuracy in predicting hemiarch patients who would experience a life-altering event. This model may help to guide patients and clinicians in stratifying risk on an individual basis, which may in turn influence clinical decision-making.

2.
Nanotechnology ; 35(29)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38631335

RESUMO

Most of the applied research on BiFeO3(BFO) focuses on magnetoelectric and spintronic applications. This calls for a detailed grasp of multiferroic and conduction properties. BFO thin films with (100) epitaxial growth has been deposited on a LaNiO3(LNO) buffered Pt/Ti/SiO2/Si(100) substrate using RF magnetron sputtering. The film formed at 15 mTorr, 570 °C, and with Ar/O24:1 had a reasonably high degree of (100)-preferential orientation, the least surface roughness, and a densely packed structure. We obtained ferroelectric loops with strong polarization (150µC cm-2). The leakage current density is as low as 10-2A cm-2at 100 kV cm-1, implying that space-charge-limited bulk conduction (SCLC) was the primary conduction channel for carriers within BFO films. Local electrical conduction behavior demonstrates that at lower voltages, the grain boundary dominates electrical conduction and is linked to the displacement of oxygen vacancies in the grain boundary under external electric fields. We hope that a deeper understanding of the conduction mechanism will help integrate BFO into viable technologies.

3.
Molecules ; 28(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067504

RESUMO

In the present research, Livistona chinensis leaf extracts were utilized as reductants to bio-fabricate silver nanoparticles (LC-AgNPs) and this was followed by the evaluation of their antioxidant, antibacterial, and anticancer potential. Multiple parameters were optimized for the formation and fidelity of LC-AgNPs. The color shift of the reaction mixture from yellow to dark brown confirmed the LC-AgNPs formation. UV/VIS spectroscopy exhibited a surface plasmon resonance (SPR) band at 436 nm. The Fourier transform infrared (FTIR) spectroscopy spectrum depicted phytochemicals in the plant extract acting as bio-reducers for LC-AgNPs synthesis. The XRD pattern confirmed the presence of LC-AgNPs by showing peaks corresponding to 2θ angle at 8.24° (111), 38.16° (200), 44.20° (220), and 64.72° (311). Zetasizer analysis exhibited size distribution by intensity of LC-AgNPs with a mean value of 255.7 d. nm. Moreover, the zeta potential indicated that the AgNPs synthesized were stable. The irregular shape of LC-AgNPs with a mean average of 38.46 ± 0.26 nm was found by scanning electron microscopy. Furthermore, the antioxidant potential of LC-AgNPs was examined using a DPPH assay and was calculated to be higher in LC-AgNPs than in leaf extracts. The calculated IC50 values of the LC-AgNPs and plant extract are 85.01 ± 0.17 and 209.44 ± 0.24, respectively. The antibacterial activity of LC-AgNPs was investigated against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis as well as Staphylococcus aureus, and maximum potential was observed after 24 h against P. aeruginosa. Moreover, LC-AgNPs exhibited maximum anticancer potential against TPC1 cell lines compared to the plant extract. The findings suggested that LC-AgNPs could be used as antioxidant, antibacterial, and anticancer agents for the cure of free-radical-oriented bacterial and oncogenic diseases.


Assuntos
Nanopartículas Metálicas , Prata , Prata/química , Antioxidantes/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Radicais Livres , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química
4.
Ann Cardiothorac Surg ; 12(5): 438-449, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37817853

RESUMO

This keynote lecture and corresponding presentation discuss the anatomy and pathophysiology surrounding spinal cord injury in aortic surgery. This article will discuss risk factors and mechanisms for spinal cord injury, including loss of direct and collateral spinal cord perfusion and ischemia-reperfusion injury. This review will examine these elements in both the laboratory and clinical setting, in addition to other neuroprotective strategies applied in clinical practice. Addressing spinal cord injury requires an integrated and considerate approach to simultaneously optimize spinal cord blood flow, promote collateralization and improve ischemic tolerance. Given the catastrophic clinical consequences for both the patient and their caregivers, continuing to investigate and examine spinal cord injury is of the utmost importance.

5.
Microorganisms ; 11(9)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37764007

RESUMO

Overuse of pesticides in agricultural soil and dye-polluted effluents severely contaminates the environment and is toxic to animals and humans making their removal from the environment essential. The present study aimed to assess the biodegradation of pesticides (cypermethrin (CYP) and imidacloprid (IMI)), and dyes (malachite green (MG) and Congo red (CR)) using biofilms of bacteria isolated from pesticide-contaminated soil and dye effluents. Biofilms of indigenous bacteria, i.e., Bacillus thuringiensis 2A (OP554568), Enterobacter hormaechei 4A (OP723332), Bacillus sp. 5A (OP586601), and Bacillus cereus 6B (OP586602) individually and in mixed culture were tested against CYP and IMI. Biofilms of indigenous bacteria i.e., Lysinibacillus sphaericus AF1 (OP589134), Bacillus sp. CF3 (OP589135) and Bacillus sp. DF4 (OP589136) individually and in mixed culture were tested for their ability to degrade dyes. The biofilm of a mixed culture of B. thuringiensis + Bacillus sp. (P7) showed 46.2% degradation of CYP compared to the biofilm of a mixed culture of B. thuringiensis + E. hormaechei + Bacillus sp. + B. cereus (P11), which showed significantly high degradation (70.0%) of IMI. Regarding dye biodegradation, a mixed culture biofilm of Bacillus sp. + Bacillus sp. (D6) showed 86.76% degradation of MG, which was significantly high compared to a mixed culture biofilm of L. sphaericus + Bacillus sp. (D4) that degraded only 30.78% of CR. UV-VIS spectroscopy revealed major peaks at 224 nm, 263 nm, 581 nm and 436 nm for CYP, IMI, MG and CR, respectively, which completely disappeared after treatment with bacterial biofilms. Fourier transform infrared (FTIR) analysis showed the appearance of new peaks in degraded metabolites and disappearance of a peak in the control spectrum after biofilm treatment. Thin layer chromatography (TLC) analysis also confirmed the degradation of CYP, IMI, MG and CR into several metabolites compared to the control. The present study demonstrates the biodegradation potential of biofilm-forming bacteria isolated from pesticide-polluted soil and dye effluents against pesticides and dyes. This is the first report demonstrating biofilm-mediated bio-degradation of CYP, IMI, MG and CR utilizing soil and effluent bacterial flora from Multan and Sheikhupura, Punjab, Pakistan.

6.
PLoS One ; 18(5): e0285284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37228116

RESUMO

OBJECTIVE: The aim of the study was to evaluate knowledge, attitude, perception, and assess the determinants of polycystic ovarian syndrome (PCOS) among undergraduate students. METHODS: A cross-sectional study was conducted among female undergraduate students in Pakistan using a survey. The questionnaire was formulated in English language by a review of literature and expert consensus. The sampling approach was convenient, and survey was available as electronic as well as hardcopy. Data were analyzed using IBM SPSS v23. Descriptive statistics namely mean ([Formula: see text]), standard deviation (SD), or median ([Formula: see text]) and interquartile range (IQR) were used dependent upon data distribution. In addition, range (R) was also utilized to express the results. The logistic and linear regression analyses were also conducted. Study received ethical clearance from ethics committees. RESULTS: A total of 646 responses were analyzed. The average PCOS knowledge score was 11.58 ± 4.99 (overall), 12.02 ± 4.73 (medical students), 9.36 ± 5.65 (non-medical students) (α = 0.861). 68.6% participants did not feel embarrassed while discussing PCOS in the society, but 67.3% never discussed it with a doctor. Lack of self-knowledge (31.6%) and shyness/reluctance (21.4%) were identified as barriers by most students. Further, obesity, irregular menstrual periods, family history, hirsutism and contraceptive use were observed to be determinants for having PCOS (AOR > 2, p<0.05). The disease knowledge score was higher for participants studying in medical college (ß = 0.184), having menstrual periods < 5 days (ß = 0.125), and with a family history (ß = 0.121) (p<0.05). CONCLUSION: The disease knowledge among undergraduates was inadequate. However, there is greater acknowledgement of PCOS as a problem for Pakistani women and barriers have been identified in the study. Conducting awareness campaigns within academic institutions which include promoting disease education, arranging talks, distributing merchandise with disease awareness signage, would greatly help in raising awareness of the disease and lowering stigma and hesitancy.


Assuntos
Síndrome do Ovário Policístico , Estudantes de Medicina , Humanos , Feminino , Paquistão/epidemiologia , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde
7.
Environ Sci Pollut Res Int ; 30(30): 74939-74951, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37209341

RESUMO

Environment-friendly textile processing is the demand of the current global scenario, where the application of sustainable technologies such as microwave radiation has been gaining fame in all global fields due to their green and human-friendly nature. This study has been conducted to employ sustainable technology such as microwave (MW) rays for dyeing polyamide-based proteinous fabric using Acid Blue 07 dye. The fabric before and after MW treatment for up to 10 min has been dyed using an acid dye solution. Spectrophotometric analysis of the dye solution was performed before and after irradiation at a specific selected level. Using selected dyes and irradiation conditions, a series of 32 experiments using a central composite design has been employed. The shades made at selected conditions of irradiation and dyeing were assessed for colorfastness as per ISO standards. It was observed that for dyeing silk, 55 mL of Acid Blue 07 dye solution containing 1 g/100 mL salt solution at 65 °C for 55 min should be employed after MW treatment for 10 min. In comparison, for dyeing wool, 55 mL of Acid Blue 07 dye solution containing 2 g/100 mL salt solution at 65 °C for 55 min should be employed after MW treatment for 10 min. Physiochemical analysis shows that sustainable tool has not altered the chemical nature of fabric but has modified the fabric surface physically to enhance uptake ability. Colorfastness shows that the shades made have offered good resistance to fade and have given good to excellent ratings on the gray scale.


Assuntos
Corantes , Seda , Animais , Humanos , Corantes/análise , Micro-Ondas , Fibra de Lã , Têxteis/análise , Lã/química
8.
Semin Cardiothorac Vasc Anesth ; 27(2): 136-144, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37098029

RESUMO

Modern cardiac surgery has rapidly evolved to treat complex cardiovascular disease. This past year boasted noteworthy advances in xenotransplantation, prosthetic cardiac valves, and endovascular thoracic aortic repair. Newer devices often offer incremental design changes while demanding significant cost increases that leave surgeons to decide if the benefit to patients justifies the increased cost. As innovations are introduced, surgeons must continuously aim to harmonize short- and long-term benefits with financial costs). We must also ensure quality patient outcomes while embracing innovations that will advance equitable cardiovascular care.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Doenças Cardiovasculares , Próteses Valvulares Cardíacas , Cirurgiões , Humanos
9.
Environ Sci Pollut Res Int ; 30(5): 12453-12465, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36112291

RESUMO

The world's move towards revival of eco-labelled products has created a huge urge to explore new means which are healthier for the global community. Among such means, plant-based bio-pigments for coloration of matrix are gaining worldwide fame, particularly in the textile sector. For the purpose of appraising new source of eco-friendly dyes, using microwave irradiation techniques, Coral Jasmine flowers have been explored for the bio-dyeing of wool. The colorant was extracted in acidic medium owing to nature of fabric, and both stuffs have been exposed to microwave treatment up to 5 min. Bio-coloration of MW irradiated and unirradiated wool was done using MW irradiated and unirradiated extract for observing high yield. Central composite design (CCD) as statistical method was utilized to see the significance of dyeing parameters chosen for mordanting to develop colorfast shades. Different concentrations of sustainable chemicals and bio-mordants as per weight of fabric were employed to introduce new shades with improved colorfastness properties. International standard textile methods determining shade permanency (fastness) have been employed onto selected dyed-mordanted fabrics. Good yield of colorant was observed when MW irradiated wool fabric was dyed at 75 °C for 45 min with extract of 7 pH, having 1.5g/100 mL of salt solution; the promising color yield was observed. As per gray scale ratings observed after ISO standard methods, pine nut as bio-mordant and iron salt as chemical mordant have developed colorfast shades. Conclusively, it can be recommended that methods for the isolation of colorants from new dye yielding plants, MW heating method as suitable clean technology and medicinal-based bio-mordants should be employed for getting permanent gamutes.


Assuntos
Jasminum , , Animais , Lã/química , Corantes/química , Flores , Extratos Vegetais/química
10.
J Thorac Cardiovasc Surg ; 165(3): e90-e99, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34763893

RESUMO

OBJECTIVES: The mitochondrial adenosine triphosphate-sensitive potassium channel is central to pharmacologically induced tolerance to spinal cord injury. We hypothesized that both direct and nitric oxide-dependent indirect activation of the adenosine triphosphate-sensitive potassium channel contribute to the induction of ischemic metabolic tolerance. METHODS: Spinal cord injury was induced in adult male C57BL/6 mice through 7 minutes of thoracic aortic crossclamping. Pretreatment consisted of intraperitoneal injection 3 consecutive days before injury. Experimental groups were sham (no pretreatment or ischemia, n = 10), spinal cord injury control (pretreatment with normal saline, n = 27), Nicorandil 1.0 mg/kg (direct and indirect adenosine triphosphate-sensitive potassium channel opener, n = 20), Nicorandil 1 mg/kg + carboxy-PTIO 1 mg/kg (nitric oxide scavenger, n = 21), carboxy-PTIO (n = 12), diazoxide 5 mg/kg (selective direct adenosine triphosphate-sensitive potassium channel opener, n = 25), and DZ 5 mg/kg+ carboxy-PTIO 1 mg/kg, carboxy-PTIO (n = 23). Limb motor function was assessed using the Basso Mouse Score (0-9) at 12-hour intervals for 48 hours after ischemia. RESULTS: Motor function was significantly preserved at all time points after ischemia in the Nicorandil pretreatment group compared with ischemic control. The addition of carboxy-PTIO partially attenuated Nicorandil's motor-preserving effect. Motor function in the Nicorandil + carboxy-PTIO group was significantly preserved compared with the spinal cord injury control group (P < .001), but worse than in the Nicorandil group (P = .078). Motor preservation in the diazoxide group was similar to the Nicorandil + carboxy-PTIO group. There was no significant difference between the diazoxide and diazoxide + carboxy-PTIO groups. CONCLUSIONS: Both direct and nitric oxide-dependent indirect activation of the mitochondrial adenosine triphosphate-sensitive potassium channel play an important role in pharmacologically induced motor function preservation.


Assuntos
Diazóxido , Traumatismos da Medula Espinal , Masculino , Camundongos , Animais , Diazóxido/farmacologia , Nicorandil/farmacologia , Trifosfato de Adenosina/metabolismo , Canais de Potássio , Óxido Nítrico/metabolismo , Camundongos Endogâmicos C57BL , Isquemia
12.
Am J Surg ; 224(4): 1057-1061, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35934556

RESUMO

BACKGROUND: The appropriate stent length in frozen elephant trunk replacements (FET) remains debated relative to the risk for paraplegia. However, landing the distal end of the stent beyond the curve of the arch facilitates distal reintervention, which is commonly beyond the 10 cm stent coverage when deployed proximal to the left subclavian artery. The aim of this study was to evaluate outcomes following the use of 15 cm stent grafts in zone 2 (z2, distal to the left common carotid). METHODS: Using our single institution-maintained database, 103 zone 2 FET performed from 2016 to 2020 were reviewed. RESULTS: Of the 103 z2, a 15 cm stent graft was used in 51 operations. The indications for FET included acute and chronic aortic dissection, arch aneurysms, and pseudoaneurysms. The incidence of SCI was 0%. Seven deaths (13.7%) occurred. CONCLUSIONS: The data demonstrates the incidence of post-operative paraplegia to be 0% with 15 cm z2 FET. The understanding of SCI in FET should not only include the stent length but also from where it begins.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Isquemia do Cordão Espinal , Aorta Torácica , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Humanos , Paraplegia/etiologia , Paraplegia/cirurgia , Estudos Retrospectivos , Isquemia do Cordão Espinal/complicações , Isquemia do Cordão Espinal/etiologia , Stents/efeitos adversos , Resultado do Tratamento
13.
Semin Cardiothorac Vasc Anesth ; 26(2): 154-161, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35591803

RESUMO

Cardiac surgery continues to evolve. The last year has been notable for many reasons. The guidelines for coronary revascularization introduced significant discord. The pandemic continues to affect the care on a global scale. Advances in organ procurement and dissection care move forward with better understanding and better technology.


Assuntos
COVID-19 , Procedimentos Cirúrgicos Cardíacos , Transplante de Coração , Obtenção de Tecidos e Órgãos , Morte , Humanos
17.
Semin Thorac Cardiovasc Surg ; 34(1): 28-38, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33444762

RESUMO

There are currently no clinically utilized pharmacological agents for the induction of metabolic tolerance to spinal cord ischemia-reperfusion injury in the setting of complex aortic intervention. Nicorandil, a nitric oxide donor and ATP-sensitive potassium (KATP) channel opener, has shown promise in neuroprotection. However, the optimized clinical application of the drug and its mechanism of neuroprotection remains unclear. We hypothesized that 3-days pretreatment would confer the most effective neuroprotection, mediated by mitochondrial KATP channel activation. Spinal cord injury was induced by 7 minutes of thoracic aortic cross-clamping in adult male C57BL/6 mice. Time course: mice received 0.1 mg/kg nicorandil for 10 min, 4 hours, and 3 consecutive days prior to ischemia compared with control. Dose challenge: mice received 3-days nicorandil pretreatment comparing 0.1 mg/kg, 1.0 mg/kg, 5.0 mg/kg, and saline administration. Mitochondrial KATP channel blocker 5-hydroxy-decanoate (5HD) was co-administered to elucidate mechanism. Limb motor function was evaluated, and viable anterior horn neurons quantified. Nicorandil pretreatment at 4 hours and 3 days before ischemia demonstrated significant motor function preservation; administration 10 minutes before ischemia showed no neuroprotection. All nicorandil doses showed significant motor function preservation. Three days administration of Nicorandil 1.0 mg/kg was most potent. Neuroprotection was completely abolished by 5HD co-administration. Histological analysis showed significant neuron preservation with nicorandil pretreatment, which was attenuated by 5HD co-administration. Three days administration of Nicorandil 1.0 mg/kg showed near-total motor function preservation in a murine spinal cord ischemia-reperfusion model, mediated by the mitochondrial KATP channel.


Assuntos
Traumatismo por Reperfusão , Isquemia do Cordão Espinal , Animais , Modelos Animais de Doenças , Humanos , Isquemia , Canais KATP , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nicorandil/farmacologia , Nicorandil/uso terapêutico , Isquemia do Cordão Espinal/etiologia , Isquemia do Cordão Espinal/prevenção & controle , Resultado do Tratamento
19.
J Thorac Cardiovasc Surg ; 163(4): 1378-1387, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-32739165

RESUMO

OBJECTIVES: Baseline kidney function is a key predictor of postoperative morbidity and mortality. Whether an increased creatinine at the time of surgery, compared with the lowest creatinine in the 3 months before surgery, is associated with poor outcomes has not been evaluated. We examined whether creatinine elevations from "baseline" were associated with adverse postoperative outcomes. METHODS: A total of 1486 patients who underwent cardiac surgery at the University of Colorado Hospital between January 2011 and May 2016 met inclusion criteria. "Change in creatinine from baseline" was defined as the difference between the immediate presurgical creatinine value and the lowest creatinine value within 3 months preceding surgery. Outcomes evaluated were in-hospital mortality, postoperative infection, postoperative stroke, development of stage 3 acute kidney injury, intensive care unit length of stay, and hospital length of stay. Outcomes were adjusted using a balancing score to account for differences in patient characteristics. RESULTS: There were significant increases in the odds of postoperative infection (odds ratio, 1.17; confidence interval, 1.02-1.34; per 0.1 mg/dL increase in creatinine), stage 3 acute kidney injury (odds ratio, 1.44; confidence interval; 1.18-1.75), intensive care unit length of stay (odds ratio, 1.13; confidence interval, 1.01-1.26), and hospital length of stay (odds ratio, 1.09; confidence interval, 1.05-1.13). There was a significant increase in mortality in the unadjusted analysis, although not after adjustment using a balancing score. There was no association with postoperative stroke. CONCLUSIONS: Elevations in creatinine at the time of surgery above the "baseline" level are associated with increased postoperative morbidity. Baseline creatinine should be established before surgery, and small changes in creatinine should trigger heightened vigilance in the postoperative period.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Creatinina/análise , Complicações Pós-Operatórias , Injúria Renal Aguda/epidemiologia , Biomarcadores/análise , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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