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1.
Toxins (Basel) ; 12(7)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610508

RESUMO

Ergot alkaloids are novel pharmaceutical and therapeutic agents synthesized in this study using fungal species Penicillium citrinum. To get the maximum yield of ergot alkaloids a statistical process of response surface methodology was employed using surface culture fermentation technique. Initially, the strain of Penicillium was improved using physical (ultraviolet (UV) and chemical (ethyl methane sulfonate (EMS) treatments to get the maximum yield of ergot alkaloids through surface culture fermentation technique. After improving the strain, survival rate of colonies of Penicillium citrinum treated with UV and EMS was observed. Only 2.04% living colonies were observed after 150 min of exposure of Penicillium citrinum in UV light and 3.2% living colonies were observed after 20 min of the exposure in EMS. The mutated strains of Penicillium citrinum were screened for their production of ergot alkaloids and after fermentation experiments, maximum yield was obtained from PCUV-4 and PCEMS-1 strains. After strain improvement, Plackett-Burman design (PBD) and Box-Behnken design (BBD) of RSM were employed and 10-fold yield enhancement (35.60 mg/100 mL) of ergot alkaloids was achieved. This enhancement in yield of ergot alkaloids proved the positive impacts of RSM and UV on the yield of ergot alkaloids. The study provides a cost effective, economical and sustainable process to produce medically important ergot alkaloids which can be used in various pharmaceutical formulations to treat human diseases.

3.
Pediatr Surg Int ; 36(7): 843-844, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32494893

RESUMO

The quality of the images published in the original version was not satisfactory. The better version images are provided below.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32583108

RESUMO

Copper (Cu) is an abundant essential micronutrient element in various rocks and minerals and is required for a variety of metabolic processes in both prokaryotes and eukaryotes. However, excess Cu can disturb normal development by adversely affecting biochemical reactions and physiological processes in plants. The present study was conducted to explore the potential of gibberellic acid (GA3) on fibrous jute (Corchorus capsularis L.) seedlings grown on Cu mining soil obtained from Hubei Province China. Exogenous application of GA3 (10, 50, and 100 mg/L) on 60-day-old seedlings of C. capsularis which was able to grow in highly Cu-contaminated soil (2221 mg/kg) to study different morphological, physiological, and Cu uptake and accumulation in different parts of C. capsularis seedlings. According to the results, increasing concentration of GA3 (more likely 100 mg/L) alleviates Cu toxicity in C. capsularis seedlings by increasing plant growth, biomass, photosynthetic pigments, and gaseous exchange attributes. The results also showed that exogenous application of GA3 reduced oxidative stress in C. capsularis seedlings by the generation of extra reactive oxygen species (ROS). The reduction in oxidative stress in C. capsularis seedlings is because that plant has strong enzymatic antioxidants [superoxidase dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT)], which ultimately increased their activities to overcome oxidative damage in the cells/tissues. In addition to the plant growth, biomass, and photosynthesis, foliar application of GA3 also helps to increase metal (Cu) concentration in different parts of the plants when compared to 0 mg/L of application of GA3. From these findings, we can conclude that foliar application of GA3 plays a promising role in reducing ROS generation in the plant cells/tissues and increased phytoextraction of Cu in different plant parts. However, more investigation is needed on field experiments to find a combination of GA3 with a very higher concentration of Cu using fibrous C. capsularis.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32552602

RESUMO

Food adulteration has a direct impact on public health, religious faith, fair-trades, and wildlife. In the present study, a reliable and sensitive assay has been developed for verifying meat adulteration in food chain. The multiplex PCR system was optimised for identification of chicken, cow/buffalo, sheep/goat, horse/donkey, pork, and dog DNAs in a single reaction mixture simultaneously. The primers were designed using 12 S rRNA gene sequences with fragment size in the range of 113 bp to 800 bp, which can be easily visualised on agarose gel electrophoresis making the technique economical. After validation of accuracy, specificity, and sensitivity, commercially available meat products (n = 190) were screened, comprising both raw and cooked meat samples. The results demonstrated a high rate of adulteration (54.5%) in meat products. The technique developed here can be easily used for screening of different meat products for export and import purposes as well as for food inspection and livestock diagnostic laboratories.

6.
Langmuir ; 36(27): 7908-7915, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32551692

RESUMO

Nanostructures play an important role in targeting sparingly water-soluble drugs to specific sites. Because of the structural flexibility and stability, the use of template microemulsions (µEs) can produce functional nanopharmaceuticals of different sizes, shapes, and chemical properties. In this article, we report a new volatile oil-in-water (o/w) µE formulation comprising ethyl acetate/ethanol/brij-35/water to obtain the highly water-dispersible nanoparticles of an antihyperlipidemic agent, ezetimibe (EZM-NPs), to enhance its dissolution profile. A pseudoternary phase diagram was delineated in a specified brij-35/ethanol ratio (1:1) to describe the transparent, optically isotropic domain of the as-formulated µE. The water-dilutable µE formulation, comprising an optimum composition of ethyl acetate (18.0%), ethanol (25.0%), brij-35 (25.0%), and water (32.0%), showed a good dissolvability of EZM around 4.8 wt % at pH 5.2. Electron micrographs showed a fine monomodal collection of EZM-loaded µE droplets (∼45 nm) that did not coalesce even after lyophilization, forming small spherical EZM-NPs (∼60 nm). However, the maturity of nanodrug droplets observed through dynamic light scattering suggests the affinity of EZM to the nonpolar microenvironment, which was further supported through peak-to-peak correlation of infrared analysis and fluorescence measurements. Moreover, the release profile of the as-obtained EZM-nanopowder increased significantly >98% in 30 min, which indicates that a reduced drug concentration will be needed for capsules or tablets in the future and can be simply incorporated into the multidosage formulation of EZM.

7.
PLoS One ; 15(6): e0229891, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497076

RESUMO

A facile method has been developed for the synthesis of Schiff bases derived from substituted and unsubstituted 3-amino- and 4-amino-1,2,4-triazoles. Condensation of the aminotrizoles with a variety of aromatic aldehydes afforded desired Schiff bases in excellent yields in 3-5 minutes of exposure to ultra-sound. The synthesized compounds were characterized by means of IR, 1HNMR and Mass spectrometry. The synthesized compounds were also screened for their antibacterial potential against Gram-negative (Escherichia coli, Shigella sonnei, Pseudomonas aeruginosa and Salmonella typhi) and two Gram-positive (Staphylococcus aureus and Bacillus subtilis) strains.

8.
Plants (Basel) ; 9(6)2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32560128

RESUMO

Copper (Cu) is an important micronutrient for a plant's normal growth and development. However, excess amount of Cu in the soil causes many severe problems in plants-which ultimately affect crop productivity and yield. Moreover, excess of Cu contents causes oxidative damage in the plant tissues by generating excess of reactive oxygen species (ROS). The present experiment was designed to investigate the phytoextraction potential of Cu, morpho-physiological features and biochemical reaction of jute (Corchorus capsularis L.) seedlings using ethylenediaminetetraacetic acid (EDTA) of 3 mM under different Cu levels (0 (control), 50 and 100 µM) in a hydroponic nutrient solution (Hoagland). Our results showed that elevated Cu rates (50 and 100 µM) in the nutrient solution significantly reduced plant height, fresh and dry biomass, total chlorophyll content and gaseous exchange attributes in C. capsularis seedlings. As the concentration of Cu in the medium increased (50 and 100 µM), the level of malondialdehyde (MDA) and oxidative stress in C. capsularis seedlings also increased, which could have been controlled by antioxidant activity in particular plant cells. In addition, rising Cu concentration in the nutrient solution also increased Cu uptake and accumulation in roots and leaves as well as affected the ultrastructure of chloroplast of C. capsularis seedlings. The addition of EDTA to the nutrient solution significantly alleviated Cu toxicity in C. capsularis seedlings, showing a significantly increase in plant growth and biomass. MDA contents was not significantly increased in EDTA-induced plants, suggesting that this treatment was helpful in capturing ROS and thereby reducing ROS in in C. capsularis seedlings. EDTA modification with Cu, although the bioaccumulation factor in roots and leaves and translocation factor for the leaves of C. capsularis seedlings has significantly increased. These results indicate that C. capsularis has considerable potential to cope with Cu stress and is capable of removing a large quantity of Cu from the Cu-contaminated soil while using EDTA is a useful strategy to increase plant growth and biomass with Cu absorption capabilities.

9.
J Hazard Mater ; 398: 122941, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32492617

RESUMO

Tebuconazole is a widely used fungicide that may impair soil health. Presently, limited information is available on the bioremediation of tebuconazole-contaminated soil using biochar as a carrier for bacteria. In this study, we firstly isolated a tebuconazole-degrading strain and identified it as Alcaligenes faecalis WZ-2. Then, we used wheat straw-derived biochar as carrier to capture strain WZ-2 to assemble microorganism-immobilized composite. Finally, we investigated the effects of strain WZ-2 and biochar-immobilized WZ-2 on tebuconazole biodegradation, microbial enzyme activities and community composition in the contaminated soil. Results showed that, as compared to control, the strain WZ-2 and biochar-immobilized WZ-2 accelerated the degradation of tebuconazole, while reducing the half-life of tebuconazole from 40.8 to 18.7 and 13.3 days in soil, respectively. However, biochar alone than control slightly retarded the degradation of tebuconazole in soil. Though tebuconazole (10 mg/kg) negatively affected the soil enzyme activities (urease, dehydrogenase, and invertase) and microbiome community structure, the biochar-immobilized WZ-2 not only accelerated the degradation of tebuconazole but also restored native soil microbial enzyme activities and microbiome community composition. Our results suggest that a compatible combination of bacteria with biochar is an attractive and efficient approach for remediation of pesticide-contaminated soil and improvement of soil biological health.

10.
J Environ Manage ; 268: 110610, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32383643

RESUMO

Phosphorus (P) is one of the most restrictive essential elements to crop growth and development due to less availability in the soil system. Previous studies have reported the synergistic effects between molybdenum (Mo) and P fertilizer on P uptake in various crops. However, an induced long term effect of Mo on soil P dynamics in the rhizosphere and non-rhizosphere has not been reported yet in leguminous crops. In this study, a long term field experiment was conducted to explore the P transformation characteristics and bioavailability in Mo-deficient (-Mo) and Mo-enriched (+Mo) soil under leguminous (broad bean-soybean) cropping system. The results indicated that long-term Mo application increased the plant dry matter accumulation (14.23%-35.27%, for broad bean; 24.40%-37.46%, for soybean) from March-September. In rhizosphere soil, the percent decrease in pH (8.10%) under +Mo treatment of the soybean crop was recorded more during September as compared to broad bean crop. Under Mo supply, H2O-Pi fraction increased up to 28.53% and 43.67% while for NaHCO3-Pi this increase was up to 5.61% and 11.98%, respectively in the rhizosphere soil of broad bean and soybean, whereas, residual-P exhibited the highest proportion of P fractions. Moreover, compared with -Mo, +Mo treatments significantly increased the soil acid phosphatase (broad bean = 17.43 µmol/d/g; soybean = 28.60 µmol/d/g), alkaline phosphatase (broad bean = 3.34 µmol/d/g; soybean 6.35 µmol/d/g) and phytase enzymes activities (broad bean = 2.45 µmol/min/g; soybean = 5.91 µmol/min/g), transcript abundance of phoN/phoC genes and microbial biomass P (MBP) in rhizosphere soil. In crux, the findings of this study suggest that long term Mo application enhanced P bioavailability through increased available P, MBP, P related enzymes activities and their genes expressions which may represent a strategy of Mo to encounter P deficiencies in the soil system.


Assuntos
Fabaceae , Solo , Molibdênio , Fósforo , Rizosfera , Microbiologia do Solo
11.
Environ Sci Pollut Res Int ; 27(24): 30367-30377, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32462620

RESUMO

Copper (Cu), with many documented cases of Cu toxicity in agriculture lands, is becoming an increasingly common issue in and elsewhere in China. However, fibrous crop such as jute is being used as phytoremediation candidate in Cu-contaminated soils due to its huge biomass. A pot experiment was conducted using four different varieties (HT, C-3, GC, and SH) of jute grown in highly Cu-contaminated soil (2221 mg kg-1), collected from Hubei Province, China. Results from this study showed that C-3 and HT were more resistant to Cu stress, while GC and SH had a serious effect due to high concentration of Cu and a significant decrease in growth and biomass. Furthermore, Cu in roots, leaves, stem core, and bast were higher in C-3 and HT compared with GC and SH. Likewise, at post-harvesting stage, maximum Cu concentration from Cu-contaminated soil was extracted by C-3 and HT while small amount was accumulated by GC and SH. The high content of malondialdehyde (MDA) in the leaves of GC and SH indicated that Cu induced oxidative damage while the antioxidative enzyme activities of superoxidase dismutase (SOD) and peroxidase (POD) were increased to scavenge reactive oxygen species (ROS) formed during oxidative stress in the plants. Conclusively, it can be identified that when grown in Cu-contaminated soil, C-3 and HT have greater ability to grow in polluted soils and possible phytoremediation materials to revoke a large amount of Cu.


Assuntos
Cobre/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Biomassa , China , Solo
12.
Artigo em Inglês | MEDLINE | ID: mdl-32419464

RESUMO

Currently, colloidal quantum dots (CQDs)-based photodetectors are widely investigated due to their low cost and easy integration with optoelectronic devices. The requirements for a high-performance photodetector are a low dark current and a high photocurrent. Normally, photodetectors with a low dark current also possess a low photocurrent, or photodetectors with reduced dark current possess a reduced photocurrent, resulting in low detectivity. In this paper, a solution to suppress dark current and maintain a high photocurrent, i.e., use of poly(methyl methacrylate) doped with Au nanoparticles (NPs) (i.e., PMMA:Au) as an interlayer for enhanced-performance tandem photodetectors, is presented. Our experimental data showed that the dark current through the tandem photodetector ITO/PEDOT:PSS/PbS:CsSnBr3/ZnO/PMMA:Au/CuSeN/PbS:CsSnBr3/ZnO/Ag is suppressed significantly; meanwhile, a high photocurrent is maintained after a PMMA:Au interlayer has been inserted between two subdetectors. The inserted PMMA:Au interlayer acts as storage nodes for electrons, reducing the dark current through the device; meanwhile, the photocurrent can be enhanced under illumination. As a result, the specific detectivity of the tandem photodetector with 35 nm PMMA:Au interlayer was enhanced significantly from 5.01 × 1012 to 2.7 × 1015 Jones under 300 µW/cm2 532 nm illumination at a low voltage of -1 V as compared to the device without a PMMA:Au interlayer. Further, the physical mechanism of enhanced performance is discussed in detail.

13.
J Pediatr Surg ; 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32467033

RESUMO

BACKGROUND: Trichobezoar is an exceedingly rare entity in children and mimics other chronic ailments such as abdominal tuberculosis or malignancy. Delayed diagnosis and management result in various complications. The study was conducted to describe our experience with 17 consecutive cases of gastrointestinal tract (GIT) trichobezoars. MATERIALS AND METHODS: We reviewed medical records of 17 consecutive cases of GIT trichobezoar managed in our department between January 2005 and December 2018. RESULTS: There were 3 males and 14 females. The median age of presentation was 7 years. Fifteen patients (88%) presented with abdominal pain and vomiting, while 8 (47%) had abdominal distension. Seven (41%) patients developed complications secondary to the GIT trichobezoar (intussusception and gangrene in 1, small bowel obstruction in 4, gastric perforation and massive bleeding per rectum in 1, acute transient pancreatitis and hypertension in 1). At operation, 9 (54%) patients had Rapunzel syndrome, 6 (35%) had gastric trichobezoar, and 2 (12%) had small bowel trichobezoars. One patient presented with massive bleeding per rectum and gastric perforation, succumbed postoperatively. One patient developed a recurrent trichobezoar. CONCLUSION: GIT trichobezoar is rare in children and simulates chronic gastrointestinal ailments. Trichobezoars may reside in the alimentary tract, remain unnoticed for years, and become overt with the onset of complications. The majority of trichobezoars had a tail in our series. Life threatening complications can occur with delayed presentations. TYPE OF STUDY: Case series. LEVEL OF EVIDENCE: Level IV.

14.
J Ayub Med Coll Abbottabad ; 32(1): 111-114, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468768

RESUMO

BACKGROUND: Mitral stenosis (MS) is a prevalent disease in the developing world. It is a preventable disease associated with considerably high morbidity and mortality rates. Myocarditis secondary to rheumatic MS can cause left ventricular (LV) dysfunction. In majority of the case this LV dysfunction is subclinical. Recent development in imaging techniques like tissue Doppler imaging (TDI) and strain imaging enabled us to detect subclinical LV dysfunction. One such example is Global Longitudinal Strain (GLS), which is a reliable mean of assessing LV dysfunction in patients diagnosed with mitral stenosis. This study is design to determine the frequency of subclinical LV dysfunction in patients presenting with severe MS of rheumatic etiology in our institute. Objective of the study was to determine frequency of subclinical LV dysfunction by mean GLS in patients with isolated severe Rheumatic MS having normal LV Ejection fraction measured by 2D/M-mode echocardiography. It was an observational crosssectional study, conducted at Department of Cardiology, Rawalpindi Institute of Cardiology, Rawalpindi, during the period of six months from 1st January to 30th June 2016. METHODS: Fiftyfive patients with isolated severe mitral stenosis of underlying rheumatic aetiology with preserve LV function (EF>50%) were selected as per other inclusion and exclusion criteria. All patients were evaluated with detailed history, physical examination and echocardiographic examination. GLS was also noted and all other information was recorded on data collection form. RESULTS: The average age and mean GLS was 48.20±11.62 years and -19.24±1.15% respectively. Left ventricular systolic impairment in patients under study using the Global Longitudinal Strain was seen in 16.36% (9/55) cases. CONCLUSIONS: Our results suggest that GLS helps in detecting impairment of LV systolic function at an early stage in patients with mitral stenosis which helps in their risk stratification thus warranting their early management.

15.
J Fluoresc ; 30(4): 801-810, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32430862

RESUMO

The application of fluorescence spectroscopy combined with chemometrics was explored in the current study for the detection of stripe rust in wheat. The healthy and stripe rust leaves were collected from the disease screening nursery. The variations in the blue-green region and chlorophyll fluorescence intensity in leaves provides the basis for the detection of stripe rust infection. With the progress of disease, the variations in the synchronous fluorescence spectroscopy (SFS) spectrum was witnessed. SFS is an excellent tool for the simultaneous measurement of multiple compound samples, in case of plants it generates evidence regarding the occurrence of leaf fluorophore bands thus revealing the biochemical variations going on at different infection stages. Based on the results of the current study, it is inferred that p-coumaric acid has the highest intensity in healthy samples followed by the asymptomatic leaf samples, whereas the band intensity of α-tocopherol, sinapic acid, chlorogenic acid, ferulic acid, tannins, flavonoid, carotenoids and anthocyanins increases in the diseased and the asymptomatic samples accordingly to the rust infection. Principal component analysis (PCA) beautifully differentiated the healthy and the infected leaf samples. It is evident that the asymptomatic samples are grouped with the diseased samples or independently; indicating the start of disease infection, the decision that is hard to make with the visual assessments. The results of the current study suggest that the fluorescence emission and the SFS spectral signatures acquired for stripe rust could be utilized as fingerprints for early disease detection.

16.
Pediatr Surg Int ; 36(7): 835-841, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32236666

RESUMO

BACKGROUND: Esophageal replacement is a challenge to the therapeutic skills of surgeons and a technically demanding operation in the pediatric age group. Various conduits and routes have been described in the literature, each with their specific advantages and disadvantages. We carried out this retrospective study to share our experience of esophageal replacement. METHODOLOGY: This study was conducted at the department of pediatric surgery The Children's Hospital and The Institute of Child Health, Lahore. The records of patients treated for esophageal replacement were reviewed. The patients under follow-up were called for clinical evaluation and assessed of long terms complications if any. RESULTS: A total of 93 patients with esophageal replacement were included in the study. Esophageal replacement was done with gastric transposition in 84 cases (90%), colon interposition in 7 cases (7.5%) including one case of redo colonic interposition, and jejunal interposition in 2 cases (2%). Routes of esophageal replacement were trans-hiatal in 71 (76%), retrosternal in 13 (14%), and trans-hiatal with thoracotomy in 9 (10%) patients. Postoperatively, all of the conduits maintained viability. Wound infection was seen in 10 (11%), wound dehiscence in 5 (5%), anastomotic leak in 9 (10%), anastomotic stenosis in 12 (13%), fistula formation in 4 (4%), aortic injury 1 (1%), dumping syndrome 8 (9%), reflux 18 (19%), dysphagia 15 (16%) and death occurred in 12 patients (13%). CONCLUSION: There are problems with esophageal replacement in developing countries. In this context, gastric conduit appeared as the best conduit for esophageal replacement, using the trans-hiatal route for replacement, in the authors' experience.

17.
Biomolecules ; 10(4)2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32290389

RESUMO

Soil and water contamination from heavy metals and metalloids is one of the most discussed and caused adverse effects on food safety and marketability, crop growth due to phytotoxicity, and environmental health of soil organisms. A hydroponic investigation was executed to evaluate the influence of citric acid (CA) on copper (Cu) phytoextraction potential of jute (Corchorus capsularis L.). Three-weeks-old seedlings of C. capsularis were exposed to different Cu concentrations (0, 50, and 100 µM) with or without the application of CA (2 mM) in a nutrient growth medium. The results revealed that exposure of various levels of Cu by 50 and 100 µM significantly (p < 0.05) reduced plant growth, biomass, chlorophyll contents, gaseous exchange attributes, and damaged ultra-structure of chloroplast in C. capsularis seedlings. Furthermore, Cu toxicity also enhanced the production of malondialdehyde (MDA) which indicated the Cu-induced oxidative damage in the leaves of C. capsularis seedlings. Increasing the level of Cu in the nutrient solution significantly increased Cu uptake by the roots and shoots of C. capsularis seedlings. The application of CA into the nutrient medium significantly alleviated Cu phytotoxicity effects on C. capsularis seedlings as seen by plant growth and biomass, chlorophyll contents, gaseous exchange attributes, and ultra-structure of chloroplast. Moreover, CA supplementation also alleviated Cu-induced oxidative stress by reducing the contents of MDA. In addition, application of CA is helpful in increasing phytoremediation potential of the plant by increasing Cu concentration in the roots and shoots of the plants which is manifested by increasing the values of bioaccumulation (BAF) and translocation factors (TF) also. These observations depicted that application of CA could be a useful approach to assist Cu phytoextraction and stress tolerance against Cu in C. capsularis seedlings grown in Cu contaminated sites.

18.
Vaccine ; 38(16): 3201-3209, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32178907

RESUMO

Neisseria meningitidis is the causative agent of meningococcal meningitis and sepsis and remains a significant public health problem in many countries. Efforts to develop a comprehensive vaccine against serogroup B meningococci have focused on the use of surface-exposed outer membrane proteins. Here we report the use of virus-like particles derived from the core protein of Hepatitis B Virus, HBc, to incorporate antigen domains derived from Factor H binding protein (FHbp) and the adhesin NadA. The extracellular domain of NadA was inserted into the major immunodominant region of HBc, and the C-terminal domain of FHbp at the C-terminus (CFHbp), creating a single polypeptide chain 3.7-fold larger than native HBc. Remarkably, cryoelectron microscopy revealed that the construct formed assemblies that were able to incorporate both antigens with minimal structural changes to native HBc. Electron density was weak for NadA and absent for CFHbp, partly attributable to domain flexibility. Following immunization of mice, three HBc fusions (CFHbp or NadA alone, NadA + CFHbp) were able to induce production of IgG1, IgG2a and IgG2b antibodies reactive against their respective antigens at dilutions in excess of 1:18,000. However, only HBc fusions containing NadA elicited the production of antibodies with serum bactericidal activity. It is hypothesized that this improved immune response is attributable to the adoption of a more native-like folding of crucial conformational epitopes of NadA within the chimeric VLP. This work demonstrates that HBc can incorporate insertions of large antigen domains but that maintenance of their three-dimensional structure is likely to be critical in obtaining a protective response.

19.
Pak J Pharm Sci ; 33(1(Supplementary)): 333-342, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32122866

RESUMO

This study elicits the underlying mechanism(s) of Capparis decidua when used for different gut disorders. HPLC chromatogram of C. decidua extract (CD.Cr) and its respective fractions showed a variety of phytochemicals of which, kaempferol being in a high proportion. In mice, CD.Cr at doses of 70 and 150 mg/kg enhanced the wet feces output to 33 and 44% respectively as compared to carbachol (47.6%), while doses of 500 and 700 mg/kg, presented 41 and 70% safety against castor oil-driven diarrhea, respectively. Its flavonoid constituent, kaempferol at doses of (50 and 100 mg/kg) produced 51.7 and 82% safety when compared to nifedipine which provided 95% safety at dose of 40 mg/kg against castor oil-driven diarrhea like loperamide. In isolated jejunum preparations, C. decidua extract and its respective fractions (except pet-ether) produced atropine-sensitive inhibitory effects, whereas kaempferol and nifedipine showed atropine insensitive effects. Against high K+-induced contractions, C. decidua's fractions and kaempferol both exhibited a concentration-related non-specific inhibition while displacing the Ca++ -CRCs to right-ward with suppression in maximal response like nifedipine. In isolated rat ileal preparations, CD.Cr and respective fractions elicited atropine-sensitive gut excitatory responses. In summary, this article reports C. decidua's laxative effect through cholinergic receptor activation as well as its antidiarrheal effects, where its flavonoid constituent kaempferol produces Ca++ antagonist like activity, thus justifying C. decidua folk use in constipation and diarrhea.

20.
Nanotechnology ; 31(25): 254001, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150737

RESUMO

Heterostructures composed of nano-/micro-junctions, combining the excellent photon harvesting properties of nano-systems and the ultrafast carrier transfer of micro-systems, have a promising role in high-performance photodetectors. In this paper, a highly-sensitive trilayer self-powered perovskite-based photodetector ITO/ZnO (70 nm)/CdS (150 nm)/CsPbBr3 (200 nm)/Au, in which the CdS nanorods (NRs) layer is sandwiched between a ZnO/CsPbBr3 interface to reduce the interfacial charge carriers' recombination and the charge transport resistance, is presented. Due to the strong built-in potential and the internal driving electric-field, an ultra-high On/Off current ratio of 106 with a responsivity of 86 mA W-1 and a specific detectivity of 6.2 × 1011 Jones was obtained at zero bias under 85 µW cm-2 405 nm illumination and its rise/decay time at zero bias is 0.3/0.25 s. Therefore, the enhanced device performance strongly suggests the great potential of such a trilayer heterojunction device for use in high-performance perovskite photodetectors.

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