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1.
BMC Urol ; 24(1): 122, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867233

RESUMO

BACKGROUND: Neurogenic bladder dysfunction is a major problem for spinal cord injury (SCI) patients not only due to the risk of serious complications but also because of the impact on quality of life. The main aim of this study is to compare the rate of urinary tract infection (UTI) associated with hydrophilic-coated catheters versus uncoated polyvinyl chloride (PVC) catheters among SCI patients presenting with functional neurogenic bladder sphincter disorders. METHODOLOGY: This was a retrospective cohort study from 2005 to 2020 including adult male or female patients who have an SCI at least more than 1 month ago with neurogenic bladder dysfunction and were using intermittent catheterization (single-use hydrophilic-coated or the standard-of-care polyvinyl chloride uncoated standard catheters) at least 3 times a day to maintain bladder emptying. RESULTS: A total of 1000 patients were selected and recruited through a stratified random sampling technique with 467 (47.60%) patients in the uncoated catheter arm and 524 (52.60%) in the coated catheter groups. The three outcome measures, namely: symptomatic UTI, Bacteriuria, and pyuria were significantly higher in the group using uncoated polyvinyl chloride (PVC) catheters compared to hydrophilic-coated catheters at the rate of 79.60% vs.46.60%, 81.10% vs. 64.69, and 53.57% versus 41.79% respectively. Males, elder patients, longer duration, and severity of SCI were associated with increased risk of symptomatic UTI. CONCLUSIONS: The results indicate a beneficial effect regarding clinical UTI when using hydrophilic-coated catheters in terms of fewer cases of symptomatic UTI. Bacteriuria is inevitable in patients with long-term catheterization, however, treatment should not be started unless the clinical symptoms exist. More attention should be given to the high-risk group for symptomatic UTIs.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinaria Neurogênica , Infecções Urinárias , Humanos , Estudos Retrospectivos , Traumatismos da Medula Espinal/complicações , Masculino , Feminino , Infecções Urinárias/etiologia , Infecções Urinárias/epidemiologia , Pessoa de Meia-Idade , Adulto , Cateteres Urinários/efeitos adversos , Cateterismo Uretral Intermitente/efeitos adversos , Interações Hidrofóbicas e Hidrofílicas , Cloreto de Polivinila , Estudos de Coortes , Idoso , Cateterismo Urinário/efeitos adversos , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia
2.
Chemistry ; 29(42): e202301036, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37150751

RESUMO

Hydrogen peroxide (H2 O2 ) electrosynthesis via the 2e- Oxygen Reduction Reaction (ORR) represents a highly challenging, environmentally friendly and cost-effective alternative to the current anthraquinone-based technology. Various lightweight element hetero-doped carbon nanostructures are promising and cheap metal-free electrocatalysts for H2 O2 synthesis, particularly those containing O-functionalities. The exact role of O-containing functional groups as electroactive sites for the process remains debated if not highly controversial. Herein, we have reported on the covalent exohedral functionalization of the outer surface of extra-pure multi-walled carbon nanotubes (MWCNTs) with discrete O-functional groups as a unique approach to prepare selective electrocatalysts for the process. This kind of decoration has added fundamental tiles to the puzzling structure/reactivity relationship of O-containing carbon-based catalysts for ORR, clearing doubts on the controversial role of hydroxyl/phenol groups as key functionalities for the design of more performing 2e- ORR electrocatalysts.

3.
J Org Chem ; 88(20): 14736-14747, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37819716

RESUMO

A cascade hexadehydro-Diels-Alder (HDDA)/[3 + 2] cycloaddition reaction between tetrayne and N,N'-cyclic acylhydrazone is described. This strategy allows the efficient construction of fully substituted 2,3-dihydro-1H-indazole scaffolds which have insecticidal activity against the third instar larvae of Mythimna separata.

4.
BMC Infect Dis ; 23(1): 368, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37259050

RESUMO

BACKGROUND: Antimicrobial stewardship programs (ASPs) are an internationally recognized strategy for reducing antimicrobial resistance while maintaining patient safety. ASP activities include the restriction of broad-spectrum antibiotics, the establishment of hospital guidelines based on antibiograms, and the promotion of appropriate antibiotic use. This study aimed to determine whether the implementation of antimicrobial stewardship practices improved the effects of a peri-procedure antibiotic prophylaxis prescribed by urologists for patients with spinal cord injury/disease (SCI/D) undergoing minor urological procedures at a tertiary care hospital. METHODS: This single-group, quasi-experiment study included adult patients with SCI/D who required minor urological procedures (cystoscopy, cytobotox, cystolitholapaxy, and urodynamic study) and who were hospitalized between 2012 and 2020. RESULTS: In total, 233 patients were included in each of the pre- and post-ASP implantation groups. There was a significant reduction in antibiotic use among patients who received a pre-procedure antimicrobial prophylaxis in the post- compared to the pre-implementation group (45.9% vs. 24.46%, p < 0.0001), and there was a highly significant reduction in the post- compared to the pre-implementation group in the number who received a post-procedure prophylaxis (16.7% vs. 1.2%, p < 0.0001). CONCLUSION: ASP implementation is a highly effective strategy for reducing the use of peri-procedure antimicrobial prophylaxes in patients with SCI/D injuries undergoing minor urological procedures.


Assuntos
Anti-Infecciosos , Gestão de Antimicrobianos , Traumatismos da Medula Espinal , Adulto , Humanos , Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/métodos , Antibioticoprofilaxia/métodos , Anti-Infecciosos/uso terapêutico , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico
5.
Mol Biol Rep ; 50(7): 5791-5806, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37219668

RESUMO

BACKGROUND: Maintaining genetic diversity is of the most essential principle for a long-term conservation of plant genetic resources and could play a crucial role in their management. The genus Aegilops is one important member of wheat germplasm, and there are evidences that novel genes of this genus' species can be studied/utilized as ideal sources for the wheat cultivar improvement. The objective of this study was to dissect the genetic diversity and population structure among a set of Iranian Aegilops using two gene-based molecular markers. METHODS AND RESULTS: This study investigated the level of genetic diversity among 157 Aegilops accessions consisting of Ae. tauschii Coss. (DD genome), Ae. crassa Boiss. (DDMM genome), and Ae. cylindrica Host. (CCDD genome) belonging to NPGBI using two sets of CBDP and SCoT markers. The SCoT and CBDP primers yielded 171 and 174 fragments, out of which 145 (90.23%) and 167 (97.66%) fragments were polymorphic, respectively. The average of polymorphism information content (PIC)/ marker index (MI)/resolving power (Rp) for SCoT and CBDP markers were 0.32/3.59/16.03 and 0.29/3.01/16.26, respectively. Results of AMOVA revealed the genetic variability within species was greater than the variation observed among them (SCoT: 88% vs. 12%; CBDP: 72% vs. 28%; SCoT + CBDP: 80% vs. 20%). Based on the information obtained from both markers, the higher level of genetic diversity was found in Ae. tauschii as compared to other species. The grouping patterns obtained by Neighbor-joining algorithms, principal coordinate analysis (PCoA), and Bayesian-model-based structure were consistent with each other and resulted in grouping all studied accessions according to their genomic constitutions. CONCLUSION: The results of this study revealed a high level of genetic diversity among Iranian Aegilops germplasm. Moreover, SCoT and CBDP marker systems were efficient in deciphering DNA polymorphism and classification of Aegilops germplasm.


Assuntos
Aegilops , Aegilops/genética , Códon de Iniciação/genética , Teorema de Bayes , Irã (Geográfico) , Polimorfismo Genético/genética , Marcadores Genéticos/genética , Variação Genética/genética
6.
J Pak Med Assoc ; 73(11): 2189-2195, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38013526

RESUMO

OBJECTIVE: To analyse the effects of aluminum phosphide poisoning dosage on arterial blood gases and the clinical outcome. METHODS: The cross-sectional study was conducted at the intensive care unit of Mardan Medical Complex, Mardan, Pakistan, from January 2021 to May 2022, and comprised patients of either gender who had attempted suicide using aluminum phosphide. Data was collected using a predesigned questionnaire. Data was analysed using SPSS 26. RESULTS: Of the 116 patients, 42(36.2%) were males and 74(63.8%) were females. There were 75(64.65) survivors; 31(41.33) males and 44(58.66) females with overall mean age 26.30±9.45 years. There were 41(35.35%) non-survivors; 11(26.82%) males and 30(73.18) females with overall mean age 28.21±11.16 years.During hospitalisation, the non- survivors showed drastically decreased levels of all arterial blood gas paramters with severe clinical outcomes (p<0.05). As the number of aluminum phosphide pills increased, the chance of survival decreased (p<0.05). The non-survivors spent an average of 32.51±16.02 hours in hospital (range: 6-59 hours). CONCLUSIONS: Patients who ingested more aluminum phosphide pills had more abnormal arterial blood gas parameter with severe clinical outcomes. Also, they had lower chance of survival and unfavourable response to treatment.


Assuntos
Praguicidas , Intoxicação , Masculino , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Triticum , Estudos Transversais , Gases
7.
Phys Chem Chem Phys ; 24(30): 18265-18271, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35876328

RESUMO

Water molecules linked by hydrogen bonds are responsible for the high efficiency of bi-functional catalysts for the water-gas-shift (WGS) reaction because water can act as a proton transfer medium. Herein, we propose an associative pathway for the WGS reaction assisted by water to realize hydrogen production. Based on this pathway, we show by first-principles calculations that a large family of oxygen-terminated two-dimensional transition metal carbides and nitrides (MXenes) deposited on Au clusters are promising catalysts for the WGS reaction. Remarkably, the rate-determining barriers for *CO → *COOH on Au/Mn+1XnO2 are in the range from 0.15 eV to 0.39 eV, indicating that WGS can occur at much lower temperatures. Furthermore, a comprehensive microkinetic model is constructed to describe the turnover frequencies (TOF) for the product under the steady-state conditions. More importantly, there is a perfect linear scaling relationship between the rate-determining barriers of the WGS and the free energy of the adsorbed hydrogen. Besides, the potential energy diagrams for CO reforming reveal that the F terminations introduced in experiments have only a slight influence on the catalytic performance of the oxygen-terminated MXenes. Our work not only opens a new avenue towards the WGS reaction but also provides many ideal catalysts for hydrogen production.

8.
J Pak Med Assoc ; 72(7): 1384-1390, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36156565

RESUMO

OBJECTIVE: To identify various emerging diagnostics parameters of coronavirus disease 2019 related to disease progression and fatality. METHODS: The cross-sectional study was conducted at Mardan Medical Complex, Khyber Pakhtunkhwah, Pakistan, from February 9, 2021, to April 21, 2021, and comprised patients of either gender aged >18 years diagnosed with coronavirus disease 2019 on the basis of polymerase chain reaction testing and who were admitted to the hospital using the World Health Organisation interim guidelines. Disease progression was categorised as mild, moderate, severe and critical, and they were monitored closely till the final outcome. Data was analysed using SPSS 26. RESULTS: Of the 408 patients, 215(52.69%) were male and 193(47.30%) were female. The overall median age of the sample was 55 years (interquartile range: 18-84 years). Symptoms included cough 92(22.54%), fever 80(19.60%), shortness of breath 78(19.60%), fatigue 60(14.70%) and loss of smell and test 52(12.74%), while 46(11.27%) were asymptomatic. Azithromycin was the most used drug 304(74.50%), while antiviral Remdesivir was given to 279(68.38%) patients and hydrocortisone to 143(35.04%). Plasma treatment was given to 55(13.48%) patients and mechanical ventilation to 87(21.32%). Compared to baseline, disease progression was mild in 72(17.64%) patients, moderate 96(23.52%), severe 98(24.01%) and critical in 89(21.81%), while no change was seen 53(12.99%) cases. Severity level was significantly associated with liver and renal function parameters (p<0.05). Overall, 47(11.51%) patients died. CONCLUSIONS: Different severity levels during hospitalisation among patients of coronavirus disease 2019 were noted, and severity level was significantly associated with liver and renal function parameters.


Assuntos
COVID-19 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/uso terapêutico , Azitromicina/uso terapêutico , COVID-19/diagnóstico , Teste para COVID-19 , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Hidrocortisona , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto Jovem
9.
Curr Psychol ; : 1-8, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35194356

RESUMO

The present study's aim is to find the prevalence of two of the common indicators of mental health - depression and anxiety - and any correlation with socio-demographic indicators in the Pakistani population during the lockdown from 5 May to 25 July 2020. A cross-sectional survey was conducted using an online questionnaire sent to volunteer participants. A total of 1047 participants over 18 were recruited through convenience sampling. The survey targeted depression and anxiety levels, which were measured using a 14 item self-reporting Hospital Anxiety and Depression Scale (HADS). Out of the total sample population (N=354), 39.9% suffered from depression and 57.7% from anxiety. Binary logistical regressions indicated significant predictive associations of gender (OR=1.410), education (OR=9.311), residence (OR=0.370), household income (OR=0.579), previous psychiatric problems (OR=1.671), and previous psychiatric medication (OR=2.641). These were the key factors e associated with a significant increase in depression. Increases in anxiety levels were significantly linked to gender (OR=2.427), residence (OR=0.619), previous psychiatric problems (OR=1.166), and previous psychiatric medication (OR=7.330). These results suggest depression and anxiety were prevalent among the Pakistani population during the lockdown. Along with other measures to contain the spread of COVID-19, citizens' mental health needs the Pakistani government's urgent attention as well as that of mental health experts. Further large-scale, such as healthcare practitioners, should be undertaken to identify other mental health indicators that need to be monitored.

10.
Chemphyschem ; 22(22): 2352-2361, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34390308

RESUMO

Based on first-principles calculations, the potential of Ti2 CO2 monolayer (MXene) as a single-atom catalyst (SAC) support for 3d transition metal (TM) atoms (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) is studied for CO oxidation. We first screen the support effect according to the stability of a single metal atom and find that Sc and Ti supported on Ti2 CO2 have stronger adsorption energy than the cohesive energy of their bulk counterparts and therefore, we selected Sc and Ti supported on Ti2 CO2 for further catalytic reactions. The stability and the potential catalytic reactivity are verified by electronic structure and charge transfer analysis. Both Eley-Rideal (ER) and Langmuir-Hinshelwood (LH) mechanisms are considered in this study, and lower energy barriers of 0.002 and 0.37 eV were found in the ER mechanism compared to the LH mechanism, which are 0.25 and 0.34 eV for Sc and Ti catalysts, respectively. Moreover, kinetic ER and LH mechanisms are favorable for both Sc- and Ti/Ti2 CO2 because of the comparable energy barrier to other metals and SAC supported on 2D materials. However, Ti/Ti2 CO2 catalyst is thermodynamically unfavorable. Based on these calculations, we propose that Sc supported on Ti2 CO2 is the best catalyst for CO-oxidation. The current study not only broadens the scope of the single-atom Sc catalyst but also extends the consideration of MXene support for catalyst optimization.

11.
Appl Opt ; 60(17): 5110-5116, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143077

RESUMO

The qualitative and quantitative study of raw steatite was carried out using a pulsed nanosecond Nd:YAG laser set to fundamental harmonic (1064 nm) at atmospheric pressure. To cross-validate the data, x-ray diffraction (XRD), x-ray fluorescence (XRF) spectroscopy, and Fourier-transform infrared spectroscopy (FTIR) were used. The analysis of optical emission spectra in the wavelength range 200-720 nm showed the existence of silica (Si), magnesium (Mg), and calcium (Ca). The plasma temperature and electron number density were estimated using the Boltzmann plot and Stark-broadening line profile methods, with results at 4906 K and ${1.47}\times{{10}^{17}}\;{{\rm cm}^{- 3}}$, respectively. The quantitative study was carried out using the calibration-free laser-induced breakdown spectroscopy (CF-LIBS) process, assuming local thermodynamic equilibrium and an optically thin plasma, and the following results were obtained: Si = 63.37%, Mg = 35.95%, and Ca = 0.671%. The quantitative findings obtained using the CF-LIBS approach were consistent with those obtained using XRD, XRF, and FTIR, demonstrating the applied methods' potential to be effective and complementary for the qualitative and quantitative study of multiphase raw steatite.

12.
Ecotoxicology ; 30(6): 1108-1115, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34165678

RESUMO

Heavy metal pollution in aquatic habitats can be detrimental to both prey and predators in a food web. To investigate the potential for bio-transfer and bioaccumulation of heavy metals between specific trophic levels, 3rd instar larvae of Aedes aegypti were exposed to mercury (Hg), lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) for three consecutive generations and fed to dragonfly (Tramea cophysa) nymphs. Exposure to Hg caused the highest mortality in A. aegypti larvae and T. cophysa nymphs. Bioaccumulation and life-history parameters of A. aegypti, including egg hatching time, larval and pupal duration, male and female life span, and fecundity, were also evaluated after metals exposure. All life-history parameters except larval duration were significantly affected by heavy metal treatments. Bioaccumulation of metals in A. aegypti larvae and adults gradually and significantly increased from 1st to 3rd generation. To the best of our knowledge, this is the first study describing the acute toxicity of heavy metals to mosquitoes. Our study shows that heavy metals cause dietary toxicity to an aquatic predator, dragonfly, via trophic transfer, which could have considerable consequences on aquatic ecosystems.


Assuntos
Aedes , Dengue , Metais Pesados , Odonatos , Animais , Ecossistema , Feminino , Masculino , Metais Pesados/toxicidade
13.
Ecotoxicology ; 30(3): 448-458, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33674904

RESUMO

Cotesia flavipes Cameron is an important larval parasitoid exploited for the control of the spotted stem borer, Chilo partellus (Swinhoe). Several studies have evaluated the toxic effects of insecticides on C. partellus, however, little is known about non-target effects of insecticides on this parasitoid, when used to control C. partellus. This laboratory study evaluated the lethal and sublethal effects of twelve insecticides on C. flavipes. Residual toxicity tests showed that organophosphates (chlorpyrifos, triazophos and profenofos) exhibited highest contact toxicity to C. flavipes adults with a LC50 range from 0.63 to 1.05 mg a.i/l, while neonicotinoids (nitenpyram, acetamiprid and imidacloprid) were less toxic to C. flavipes with a LC50 range from 1.27 to 139.48 mg a.i/l. Sugar-insecticide feeding bioassays showed that organophosphates, pyrethroids (cypermethrin, bifenthrin and lambda-cyhalothrin) and carbamates (thiodicarb, carbaryl and methomyl) were highly toxic to C. flavipes adults and caused 100% mortality at 48 h of exposure, while imidacloprid caused 66% mortality at 48 h of exposure. Risk quotient analysis showed that among all tested insecticides, imidacloprid and acetamiprid were less toxic to C. flavipes adults with a risk quotient value of 0.88 and 1.6, respectively. Furthermore, exposure of immature C. flavipes through their host bodies significantly decreased the parasitism rate at their F1 and F2 generations. Risk quotient analysis of insecticides indicated that imidacloprid and acetamiprid were the least toxic to C. flavipes. This study provides important information that will be used in incorporating the most suitable insecticides in integrated pest management programs with reduced negative impacts on non-target beneficial arthropods.


Assuntos
Inseticidas , Mariposas , Vespas , Animais , Inseticidas/toxicidade , Larva , Neonicotinoides/toxicidade , Medição de Risco
14.
Pestic Biochem Physiol ; 174: 104802, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33838703

RESUMO

The beet armyworm, Spodoptera exigua, is a highly polyphagous pest originated from Southeast Asia but has spread globally, attacking economically important crops and fruits. Bistrifluron insecticide is one of the highly active insect growth regulators that has been reported to inhibit development and longevity in other lepidopteran species and could be used in the control of S. exigua. In the present study, the age-stage, two-sex life table technique was applied to assess the sublethal effects of bistrifluron on biological traits and vitellogenin gene (SeVg) expression when 2nd instar larvae fed to sublethal concentrations (LC10, LC20 and LC40) of bistrifluron. Mean generation time from eggs to adults was longer at LC40 (37.79 ± 0.81 d) and LC20 (37.04 ± 0.72) compared to the LC10 (36.89 ± 0.63 d) and control groups (36.07 ± 0.38 d). Fecundity of female at LC40 (279.17 ± 42.8 eggs), LC20 (347 ± 35.4 eggs) and LC10 (411.58 ± 42.38 eggs) were significantly lower than the control treatment (532.47 ± 7.13). Furthermore, the lower intrinsic rates of increase (LC40; r = 0.1207 ± 0.009, LC20; r = 0.1329 ± 0.009 and LC10; r = 0.14398 ± 0.009 compared to the control r = 0.164 ± 0.0076), was observed along with significantly extended mean generation times (LC40; T = 34.825 ± 0.317 days, LC20; T = 33.27 ± 0.368 days and LC10; T = 31.899 ± 0.398 days compared to the control 30.927 ± 0.255 days). Furthermore, the contents of energy reserve macronutrients (carbohydrate, lipid and protein) significantly reduced in dose and time dependent manner in treated insects as compared to control. Furthermore, the expression level of SeVg mRNA significantly decreased by 43.8% in the female adults when one-day-old second instar larvae were treated with sublethal concentrations of bistrifluron in comparison with the control. Documenting these sublethal effects is a vital, and often overlooked factor, in assessing the overall efficacy of insecticides in the management of pest populations.


Assuntos
Inseticidas , Vitelogeninas , Animais , Feminino , Hidrocarbonetos Halogenados , Inseticidas/toxicidade , Larva , Nutrientes , Compostos de Fenilureia , Spodoptera/genética , Vitelogeninas/genética
15.
Molecules ; 26(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067793

RESUMO

As an important moiety in natural products, N,O-acetal has attracted wide attention in the past few years. An efficient method to construct N,O-acetal has been developed. Using silver catalyst, cyclobutenediones were smoothly converted to the corresponding γ-aminobutenolides in the presence of formamides, in which cyclobutenediones likely proceed with a key decarbonylative [3 + 2] cycloaddition process. In this way, a series of products with varied substituents were isolated in moderate yield and fully characterized.

16.
Pestic Biochem Physiol ; 162: 6-14, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31836055

RESUMO

The beet armyworm (Spodoptera exigua) is a highly polyphagous agricultural pest that is distributed worldwide. However, the adaptive mechanisms of S. exigua for various insecticides and defensive substances in host plants are unknown. Insect P450 monooxygenases play an important role in the detoxification of plant toxins and insecticides, leading to insecticides resistance. We investigated the induced effects of xanthotoxin exposure on detoxification enzyme activity and larval tolerance to α-cypermethrin in S. exigua. Our results showed that the lethal concentration (LC50) of α-cypermethrin for xanthotoxin-exposed larvae was 2.1-fold higher than in the control. Moreover, cytochrome P450 enzyme activity was significantly elevated by upregulation of P450 genes in treated larvae. RT-qPCR results showed that CYP9A10 expression level was significantly increased in all treatments, while maximal expression level was observed in xanthotoxin+α-cypermethrin-fed larvae. RNAi-mediated silencing of CYP9A10 further increased mortality by 18%, 26% and 35% at 48 h and by 27%, 43% and 55% at 72 h when larvae were exposed to diets containing chemicals as compared to the control. The results show that CYP9A10 might play an important role in xanthotoxin and α-cypermethrin detoxification in S. exigua. RNAi-mediated silencing could provide an effective synergistic agent for pest control or insecticide resistance management.


Assuntos
Inseticidas , Metoxaleno , Animais , Sistema Enzimático do Citocromo P-450 , Larva , Piretrinas , Interferência de RNA , Spodoptera
17.
J Am Chem Soc ; 141(7): 2975-2983, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677301

RESUMO

Classical strong metal-support interactions (SMSI), which play a crucial role in the preparation of supported metal nanoparticle catalysts, is one of the most important concepts in heterogeneous catalysis. The conventional wisdom for construction of classical SMSI involves in redox treatments at high-temperatures by molecular oxygen or hydrogen, sometimes causing sintered metal nanoparticles before SMSI formation. Herein, we report that the aforementioned issue can be effectively avoided by a wet-chemistry methodology. As a typical example, we demonstrate a new concept of wet-chemistry SMSI (wcSMSI) that can be constructed on titania-supported Au nanoparticles (Au/TiO2-wcSMSI), where the key is to employ a redox interaction between Auδ+ and Ti3+ precursors in aqueous solution. The wcSMSI is evidenced by covering Au nanoparticles with the TiO x overlayer, electronic interaction between Au and TiO2, and suppression of CO adsorption on Au nanoparticles. Owing to the wcSMSI, the Au-TiO x interface with an improved redox property is favorable for oxygen activation, accelerating CO oxidation. In addition, the oxide overlayer efficiently stabilizes the Au nanoparticles, achieving sinter-resistant Au/TiO2-wcSMSI catalyst in CO oxidation.

18.
Appl Opt ; 58(27): 7588-7596, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674413

RESUMO

Bauxite is a primary ore of aluminum. Precise information about bauxite mineralogical composition is challenging and crucial for efficient aluminum extraction and for the determination of its appropriateness for different industrial applications. For the qualitative and quantitative analysis of bauxite ore, we performed laser-induced breakdown spectroscopy (LIBS) in conjunction with x-ray diffraction (XRD), x-ray fluorescence spectroscopy (XRF), scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (SEM-EDS), and Fourier transform infrared spectroscopy (FTIR). Analysis of the acquired optical emission spectrum revealed the presence of Si, Al, Fe, K, Ti, Ca, Mg, Na, Cr, and Sr. The plasma temperature and electron number density values estimated using Boltzmann plot and Stark-broadening line profile methods were 5600 K and 7.65×1017 cm-3, respectively. In the present study we show that a calibration-free LIBS method presents a powerful solution, enabling quantitative analysis of multi-element bauxite ore better than traditional analytical techniques. The bauxite quantification obtained using CF-LIBS under the assumption of local thermodynamic equilibrium and optically thin plasma was Si=47.31%, Al=31.90%, Fe=16.54%, K=2.45%, Ti=1.64%, and Ca=0.16%, and its comparison with the outcome from XRD, XRF, SEM-EDS, and FTIR not only assisted but potentially enhanced the mineralogical composition understanding of bauxite ore in the present study.

19.
J Org Chem ; 83(15): 7694-7713, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29878776

RESUMO

A straightforward protocol integrating a sustainable approach for the synthesis of new 2,5- trans-THF nitrile derivatives enabling an easy diversification of its side chain scaffolds is described. The reaction tolerated different aromatic and alkyl substituents, affording the corresponding 2,5- trans-THFs in high diastereoselectivity. A detailed mechanistic study using DFT calculation reveals details of the ligand-exchange step, suggesting an inner-sphere syn attack to form the 2,5- trans stereochemistry as the most likely pathway, excluding the previous cation radical intermediate. The formation of a Co-C intermediate is suggested on the basis of the homolytic cleavage to give the previously proposed free carbon radical intermediate.

20.
Ecotoxicol Environ Saf ; 163: 382-390, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30059883

RESUMO

Insecticides, essential for crop protection measures, leave behind several toxic residues that can result in a series of human health disorders. Therefore, this study was planned for the determination of residues and adverse effects of insecticides in blood samples of sprayers, pesticide-industry workers and controls by using blood parameters of these individuals as biomarkers. Optimized analytical methods using GC-MS and HPLC for the simultaneous detection of 22 currently used insecticides were adopted. Eight of twenty-seven (22.22%) sprayers' blood samples were found positive for five different insecticides. Eleven of twenty-seven (40.74%) pesticide-industry workers were found positive for eight different insecticides. The blood samples of both the exposed groups, sprayers and industry workers had significantly (P < 0.001; Mann-Whitney U-tests) low hemoglobin-Hb concentrations (12.17 ±â€¯2.13 and 12.22 ±â€¯2.37 g/dl respectively) than the average value of the control group with 14.23 ±â€¯2.37 g/dl. The erythrocyte sedimentation rates (ESRs) in sprayers and insecticide industry workers (28.78 ±â€¯20.72 and 28.17 ±â€¯25.14 mm/1st h respectively) were greater significantly (P < 0.001; Mann-Whitney U test) than the control blood samples (9.53 ±â€¯3.34 mm/1st h). These results indicate that the exposed individuals have experienced significant hemotoxic effects during insecticide exposure. The study also predicts the risk to exposed individuals in developing countries like Pakistan and demands realization of safety measures to prevent such dangerous effects of pesticide exposures.


Assuntos
Inseticidas/sangue , Exposição Ocupacional/análise , Resíduos de Praguicidas/sangue , Adulto , Biomarcadores , Hemoglobinas , Humanos , Inseticidas/toxicidade , Exposição Ocupacional/efeitos adversos , Paquistão , Resíduos de Praguicidas/toxicidade , Praguicidas , Adulto Jovem
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