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1.
Clin Genet ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38774940

RESUMO

Skeletal dysplasias are a heterogeneous group of disorders presenting mild to lethal defects. Several factors, such as genetic, prenatal, and postnatal environmental may contribute to reduced growth. Fourteen families of Pakistani origin, presenting the syndromic form of short stature either in the autosomal recessive or autosomal dominant manner were clinically and genetically investigated to uncover the underlying genetic etiology. Homozygosity mapping, whole exome sequencing, and Sanger sequencing were used to search for the disease-causing gene variants. In total, we have identified 13 sequence variants in 10 different genes. The variants in the HSPG2 and XRCC4 genes were not reported previously in the Pakistani population. This study will expand the mutation spectrum of the identified genes and will help in improved diagnosis of the syndromic form of short stature in the local population.

2.
Nanotechnology ; 35(6)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37879320

RESUMO

Nickel-based oxides are selected for their inexpensive cost, well-defined redox activity, and flexibility in adjusting nanostructures via optimization of the synthesis process. This communique explores the field of energy storage for hydrothermally synthesized NiO/ZnO nanowires by analysing their capacitive behaviour. The p-type NiO was successfully built onto the well-ordered mesoporous n-type ZnO matrix, resulting in the formation of p-n heterojunction artefacts with porous nanowire architectures. NiO/ZnO nanowire-based electrodes exhibited much higher electrochemical characteristics than bare NiO nanowires. The heterojunction at the interface between the NiO and ZnO nanoparticles, their specific surface area, as well as their combined synergetic influence, are accountable for the high specific capacitance (Cs) of 1135 Fg-1at a scan rate of 5 mV s-1. NiO/ZnO nanowires show an 18% dip in initial capacitance even after 6000 cycles, indicating excellent capacitance retention and low resistance validated by electrochemical impedance spectroscopy. In addition, the specific capacitance, energy and power density of the solid state asymmetric capacitor that was manufactured by employing NiO/ZnO as the positive electrode and activated carbon as the negative electrode were found to be 87 Fg-1, 23 Whkg-1and 614 Wkg-1, respectively. The novel electrode based on NiO/ZnO demonstrates excellent electrochemical characteristics all of which point to its promising application in supercapacitor devices.

3.
J Mol Recognit ; 28(12): 699-709, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26086855

RESUMO

The biological cells and extracellular matrix exhibit a highly crowded environment, called as macromolecular crowding. Crowding significantly influences protein structure and may lead to its aggregation. In the present study, buffalo heart cystatin (BHC), after purification from buffalo heart tissue, has been used as a model protein for studying effect of macromolecular crowding in the presence of high concentrations of bovine serum albumin (BSA), poly-ethylene glycol-1000 (PEG-1000), and poly-ethylene glycol-4000 (PEG-4000). Cystatins are thiol protease inhibitors and found to be involved in various important physiological processes. Functional inactivation of BHC was observed upon crowding, which varied as a function of concentration and molecular weight of crowding agents as well as incubation time. Structural changes of BHC at tertiary and secondary level were detected with the help of fluorescence and CD spectroscopy. CD analysis showed changes of α-helix to ß-sheet, which could be due to aggregation. The ANS-fluorescence study suggested the unfolding and presence of some partially folded intermediates. Increase in ThT-fluorescence and absorption of Congo red spectra with red shift, confirmed the amyloid type aggregation of BHC in the presence of various crowding agents. Finally, electron microscopy provided the physical evidence about the formation of amyloid fibrils. Results suggested that among the various crowding agents used, amyloidogenesis of BHC was maximal in case of BSA followed by PEG-4000 and least for PEG-1000. The present work makes an important contribution in crowding mediated protein aggregation, which can have implications of potential interest.


Assuntos
Amiloide/metabolismo , Cistatinas/metabolismo , Miocárdio/metabolismo , Dobramento de Proteína , Animais , Búfalos/metabolismo , Dicroísmo Circular , Microscopia Eletrônica , Complexos Multiproteicos , Miocárdio/patologia , Polietilenoglicóis/metabolismo , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência
4.
J Fluoresc ; 24(4): 1107-17, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24789772

RESUMO

The study shows the effect of nonenzymatic glycation on conformation and inhibitory activity of chick pea cystatin (CPC). CPC was incubated with different reducing sugars, pentose (D-Ribose), hexoses (D-Glucose, D-Fructose) at 37 °C for 5 weeks. To evaluate the modification of CPC by these different sugars during the glycation process the extent of the Maillard reaction, conformational, structural and functional changes were investigated. The behaviour of glycated CPC was monitored by the techniques of UV and fluorescence spectroscopies. Specific fluorescence was employed to characterise the glycation and AGEs. The anti-papain activity of glycated CPC was found to be significantly lower as compared to its non-glycated form. Glycation with ribose led to maximum loss in inhibitory activity. It was found that the incubation of CPC with all the mentioned sugars led to a parallel increase in tryptophan fluorescence as well as in Maillard and other AGEs specific fluorescence values and hyperchromicity in the UV-region. Among the sugars studied comparatively ribose was found to be the most active in inducing structural and conformational alterations in the protein suggesting its high reactivity with protein amino groups.


Assuntos
Cistatinas/química , Cicer/química , Cistatinas/isolamento & purificação , Glicosilação , Sementes/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
5.
Int J Biol Macromol ; 266(Pt 2): 131149, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556232

RESUMO

Northern corn leaf blight caused by Setosphaeria turcica is a major fungal disease responsible for significant reductions in maize yield worldwide. Eukaryotic type 2A protein phosphatase (PP2A) influences growth and virulence in a number of pathogenic fungi, but little is known about its roles in S. turcica. Here, we functionally characterized S. turcica StPP2A-C, which encodes the catalytic C subunit of StPP2A. StPP2A-C deletion slowed colony growth, conidial germination, and appressorium formation but increased conidiation, melanin biosynthesis, glycerol content, and disease lesion size on maize. These effects were associated with expression changes in genes related to calcium signaling, conidiation, laccase activity, and melanin and glycerol biosynthesis, as well as changes in intra- and extracellular laccase activity. A pull-down screen for candidate StPP2A-c interactors revealed an interaction between StPP2A-c and StLac1. Theoretical modeling and yeast two-hybrid experiments confirmed that StPP2A-c interacted specifically with the copper ion binding domain of StLac1 and that Cys267 of StPP2A-c was required for this interaction. StPP2A-C expression thus appears to promote hyphal growth and reduce pathogenicity in S. turcica, at least in part by altering melanin synthesis and laccase activity; these insights may ultimately support the development of novel strategies for biological management of S. turcica.


Assuntos
Ascomicetos , Domínio Catalítico , Regulação Fúngica da Expressão Gênica , Melaninas , Proteína Fosfatase 2 , Esporos Fúngicos , Melaninas/biossíntese , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/enzimologia , Esporos Fúngicos/crescimento & desenvolvimento , Proteína Fosfatase 2/metabolismo , Proteína Fosfatase 2/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Zea mays/microbiologia
6.
J Trace Elem Med Biol ; 84: 127454, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38669815

RESUMO

BACKGROUND: The perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. METHODS: The present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. RESULTS: The mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59 ±â€¯1.66) > Fe (11.39 ±â€¯0.99) > Zn (6.62 ±â€¯0.89) > Cu (5.86 ±â€¯0.62) > Co (3.25 ±â€¯0.64) > Ni (1.69 ±â€¯0.23) > Pb (1.08 ±â€¯0.16) > Cr (0.57 ±â€¯0.09) > Cd (0.46 ±â€¯0.09) > Al (0.05 ±â€¯0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HI < 1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. CONCLUSION: Elevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.


Assuntos
Chá , Chá/química , Análise Multivariada , Análise de Componente Principal , Carcinógenos/análise , Oligoelementos/análise , Humanos , Folhas de Planta/química , Camellia sinensis/química
8.
Appl Health Econ Health Policy ; 21(1): 11-22, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36260276

RESUMO

OBJECTIVE: We aim to develop a comprehensive checklist for evaluating Health Technology Assessment (HTA) studies commissioned in India. The primary objective of this work is to capture all vital aspects of an HTA study in terms of conduct, reporting and quality. METHODOLOGY: The development of a quality appraisal checklist included 3 steps. First, a targeted review of the literature was done to gather information on existing HTA checklists. After reviewing these checklists, an initial draft of the HTA quality appraisal checklist (HTA-QAC) for India was prepared with discussion amongst the authors. Second, the draft checklist was reviewed by the members of the Technical Appraisal Committee (TAC) and their feedback was incorporated. Subsequently, the revised checklist was presented at a virtual meeting of the TAC. Finally, a pilot phase was undertaken to apply HTA-QAC for the approved HTA study reports. Three rounds of virtual discussions were held with the researchers who were involved in the conduct of these HTA studies to resolve any discordance in opinion or develop solutions for the problems in the use of the HTA-QAC followed by a further revision of the checklist. RESULTS: The HTA-QAC is divided into two parts: a self-reporting section to be completed by the author, and the other to be completed by the reviewer. The reviewer checklist has two sections: one to review the report and the other to review the model. The author section is in a self-reporting format, which includes details of basic study information, the rationale for the study, policy relevance, study description, study methods, reporting of model parameters, and results. The reviewer section of the checklist focuses on the quality aspect of the conducted study. The domains included in the report review include details on study methodology, results, discussion, and conclusion. The second part of the reviewer section of HTA-QAC constitutes a review of the model in terms of model assumptions, functionality, model inputs, calculations, uncertainty analysis, model output, and model validation. CONCLUSION: We recommend a standardised process of quality appraisal to ensure the high quality of HTA evidence for policy use in the Indian context. The proposed HTA-QAC will help authors to ensure standardised reporting, as well as allow reviewers to assess the quality of analysis.


Assuntos
Lista de Checagem , Avaliação da Tecnologia Biomédica , Humanos , Avaliação da Tecnologia Biomédica/métodos , Projetos de Pesquisa , Índia , Políticas
9.
J Parasit Dis ; 47(3): 619-629, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37520206

RESUMO

Due to limited chemotherapeutic options for leishmaniasis, novel synthetic compounds are gaining attention for evaluation against leishmaniasis. This study aimed to synthesize the compound's Schiff bases of Vanillin to investigate and evaluate their anti-leishmanial potentials against intracellular protozoan parasites Leishmania tropica. In the current study, the phenomena of synergism by designing Schiff bases with Vanillin enhances their desired importance. A total of five compounds Schiff bases of Vanillin were synthesized using different aromatic amines and Vanillin. The structural analysis of all the compounds was done through FT-IR (Fourier Transformer-Infrared), thin layer chromatography, and spectroscopic techniques such as 13C-NMR, mass spectrometry, and 1H-NMR. The antimicrobial properties of all the compounds ZI-1, ZI-2, BS-1, KH-1, and FA-2 against promastigotes and amastigotes forms of L. tropica were analyzed at three different concentrations 25, 50, and 100 µg/ml. The in-vitro MTT assay was performed to calculate the percent inhibition, IC50 values, and their cytotoxicity. The highest percent inhibition values against promastigote form of L. tropica were BS-1 53.78% at 25 µg/ml, ZI-2 66.95% at 50 µg/ml, and again ZI-2 76.92% at 100 µg/ml. Similarly, the highest percent inhibition values against intracellular amastigote stage were BS-1 55.77% at 25 µg/ml, ZI-2 67.78% at 50 µg/ml and again ZI-2 84.93% 100 µg/ml. The highest potency was recorded for BS-1 in both stages, with IC50 values of 9.83 and 4.27 µg/ml against promastigotes and intracellular amastigotes, respectively. The percent hemolysis as toxicity; the lowest percent hemolysis was recorded for ZI-1 at three different concentrations of 25, 50, 100 µg/ml of 2.60, 3.50, and 6.31, respectively. These results suggested that all the compounds exhibited anti-leishmanial activity, with BS-1 as the most potent. Further studies are suggested to increase the activity of compounds with structural modifications by the addition of some other synergistic, novel, and analogue compounds.

10.
Bioinorg Chem Appl ; 2022: 2694487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340420

RESUMO

The carbonaceous adsorbents, an activated carbon (AC) and a bioinorganic nanocomposite (MAC), were prepared using Dalbergia sissoo sawdust as waste biomass, in this study. Both the adsorbents were characterized by FTIR, EDX, SEM, XRD, TG/DTA, surface area, and a pore size analyzer. The adsorbents were used for the removal of an antibiotic, doxycycline (DC) antibiotic, from wastewater in order to minimize a load of antibiotics in industrial effluents and consequently the drug resistance problem. Initially, the effectiveness of adsorbent was confirmed using batch adsorption experiments where isothermal models like Langmuir, Freundlich Temkin, Jovanovic, and Harkins-Jura were utilized to govern the maximum adsorption capacity of AC and MAC while pseudo-first- and second-order kinetic models were used to estimate the values of different kinetic parameters. Langmuir model best accommodated the equilibrium data whereas the pseudo-second-order kinetic model finest trimmed the kinetics data. The effect of pH on adsorption was also evaluated where maximum removal was observed between pH 5 and 7 by both adsorbents. The effect of temperature on adsorption was evaluated where the entropy change (ΔS 0) comes out to have a numerically positive value whereas Gibbs free energy change (ΔG 0) and enthalpy change (ΔH 0) were negative indicating the spontaneous nature and feasibility of the procedure. The robust technology of membrane separation is rapidly replacing the conventional technologies but at the same time suffers from the problem of membrane fouling. As pretreatment, the AC and MAC were used in hybrid with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes whereas permeate fluxes and percent retention of DC were compared for naked membrane operations and AC/membrane and MAC/membrane process. The permeate fluxes for MAC/membrane processes were greater as compared to AC/membrane and naked membrane processes showing the effectiveness of the bioinorganic composite as foul control and consequently recovery of DC from effluents. The percent retention of the UF membrane was lower as compared to NF and RO membranes. Improvement in percent retention for UF/AC, UF/MAC, NF/AC, NF/MAC, RO/AC, and RO/MAC was observed. The bioinorganic composite MAC contains a magnetic iron oxide which was effectively removed from slurry after use through the magnetic process and that was the main reason for high permeate fluxes in MAC/membrane operations.

11.
J Parasit Dis ; 46(2): 366-376, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35692473

RESUMO

Polymer based nanoparticles for drug delivery is an alternative approach to overcome drug resistance and drug toxicity especially for cutaneous leishmaniasis treatment. The present study shows synthesis and characterization of Miltefosine loaded chitosan nanoparticles (MFS-CNPs). The synthesized MFS-CNPs were experimented to evaluate the in vitro cytotoxicity and efficacy of the synthesized drug loaded nanoparticles by hemolysis assay and 3-(4, 5- dimethylthiazol-2-yl)-2,5-diphenyletetrazolium bromide (MTT) assay. MFS-CNPs were synthesized by ionic gelation method with sodium tripolyphosphate. The characterization of synthesized NPs was performed to observe the surface morphology, encapsulation efficacy, drug loading content, average size, and zeta potential. In vitro MTT assay was performed to calculate half maximal inhibitory concentration value of synthesized nanoparticles against promastigotes and axenic amastigotes of L. tropica. By using Scanning electron microscope, MFS-CNPs displayed spherical shape having a mean size of 70 nm along with high EE (97%), DLC (91%) and negative surface charge (- 28.0 mV). Dynamic light scattering shows the average size of NPs was 91.4 nm. Moreover, less than 5% hemolytic activity was observed in MFS-CNPs as compared to free MFS in different concentrations (100 µg/ml, 125 µg/ml, 150 µg/ml).It was observed that the effect of MFS-CNPs and free MFS on both forms of the parasite was dose and time dependent. However, the cytotoxic effects of MFS-CNPs were more salient than free MFS on both forms of L. tropica. Using MTT assay, free MFS presented low efficacy at higher concentrations (30 µg/ml) with 21.4 ± 1.3 and 20.5 ± 1.4 mean viability rate of the promastigotes and axenic amastigotes, respectively after 72 h incubation. While MFS-CNPs showed strong antileishmanial effects on both forms of L. tropica (11 ± 0.3 and 14 ± 0.8) mean viability rate after 72 h incubation at (30 µg/ml). When analyzed statistically by the software, Graph Pad Prism version 5, the IC50 value of MFS-CNPs (0.0218 ± 0.01 µg/ml) against promastigotes was effective than free MFS (0.3548 ± 0.17 µg/ml). Similarly, MFS-CNPs activity against axenic amastigotes (0.1008 ± 0.02 µg/ml) was potent than free MFS (0.5320 ± 0.21 µg/ml). Hence, MFS-CNPs exhibited significant antileishmanial activity in vitro. In conclusion, MFS-CNPs manifested enhanced in vitro Leishmanicidal and less hemolytic activity; however more studies are needed to support its efficacy in both animal and human cutaneous leishmaniasis.

12.
Biomed Res Int ; 2022: 2323078, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36875821

RESUMO

Type 2 diabetes mellitus (T2DM) is one of the most common forms of diabetes. We are living in the middle of a global diabetes epidemic. Emerging pieces of evidence are suggesting the increased expression of protein tyrosine phosphatase 1B (PTP1B) in the pancreas and adipose tissues during T2DM. The negative regulation of the insulin signaling pathway by PTP1B helps the researchers to consider it as a potential therapeutic target for the treatment of insulin resistance and its associated complications. From the literature, we found that compound 5,7-dihydroxy-3,6-dimethoxy-2-(4-methoxy-3-(3-methyl-2-enyl)phenyl)-4H-chromen-4-one (Viscosol) extracted from Dodonaea viscosa can inhibit PTP1B in vitro. Therefore, in this study, we aimed to evaluate the antidiabetic effect of this compound in a high-fat diet (HFD) and low-dose streptozotocin- (STZ-) induced T2DM mouse model. For this purpose, T2DM was induced in C57BL/6 male mice by using an already established protocol with minor modification. The compound-treated T2DM mice showed improvements in biochemical parameters, i.e., decrease in the fasting blood glucose level, increased body weight, improved liver profile, and reduction in oxidative stress. Furthermore, to elucidate the inhibition of PTP1B, the expression level of PTP1B was also measured at mRNA and protein levels by real-time PCR and western blot, respectively. Additionally, downstream targets (INSR, IRS1, PI3K, and GLUT4) were examined for confirming the inhibitory effect of PTP1B. Our results suggest that the compound can specifically inhibit PTP1B in vivo and might have the ability to improve insulin resistance and insulin secretion. Based on our experiment, we can confidently state that this compound can be a new PTP1B drug candidate for the treatment of T2DM in the coming future.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Hipoglicemiantes , Modelos Animais de Doenças
13.
Front Pharmacol ; 11: 550205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982753

RESUMO

BACKGROUND: Direct-acting antivirals (DAAs) therapeutic regimens are highly effective against chronic hepatitis C virus (HCV) infection. However, HCV patients with genotype 3 (GT3) respond in a suboptimal way. This study aims to identify which of the DAAs-based therapeutic regimens are the best option for GT3. METHODS: Multiple governments and private tertiary care hospitals were involved in this real-life study of HCV-GT3 patients treated with DAAs. The efficacy and safety of generic sofosbuvir+daclatasvir±ribavirin (SOF+DCV±RBV) and sofosbuvir/velpatasvir±ribavirin (SOF/VEL±RBV) were assessed under the National Hepatitis C Program of Pakistan. RESULTS: Out of 1,388 participants, 70% of patients received SOF+DCV in government tertiary care hospitals and 30% received SOF/VEL in private tertiary care hospitals. The overall sustained virological responses (SVR) was 95.5%. The SVR rates at 12 weeks were comparable between SOF+DCV (94.4%) and SOF/VEL (94.7%) in chronic HCV patients. However, The SVR rates at 24 weeks were high in cirrhotic patients treated with SOF/VEL+RBV (88%) then SOF+DCV+RBV (83%). Non-responders were high in SOF-DCV than SOF-VEL (4.1 vs 3.8%, P = 0.05) regimen. In multivariate models, the significant predictors of non-SVR were age >60 years (odds ratio [OR] 4.46; 95% CI, 2.35-8.46, P = <0.001) and cirrhosis (OR 53.91; 95% CI, 26.49-109.6, P = <0.001). Skin rash (51 vs 44%) and oral ulcers (45 vs 40%) were high in patients receiving SOF-DCV then SOF-VEL. CONCLUSIONS: Overall, the generic SOF+DCV ±RBV and SOF/VEL ± RBV achieved equally high SVR12 rates. However, SOF/VEL+RBV achieved a high SVR rate in cirrhotic patients then SOF+DCV+RBV. Old age and cirrhosis were significant predictors of reduced odds of SVR regardless of the regimen. Furthermore, the regimens were well tolerated in chronic HCV patients.

14.
Microsc Res Tech ; 83(7): 755-766, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32118344

RESUMO

In the present study, we evaluate the importance of foliar epidermal micromorphological characteristics of Apocyanaceae for accurate identification and classification. The species were collected from the University of Peshawar's main campus in the spring season to observe its qualitative and quantitative features. The length and width of guard cells, stomatal pore and subsidiary cells, trichomes, and crypts on both sides of the leaf were examined. Many species were observed to be hypostomatic. Plumeria rubra, Raulfia serpentine, Thevetia peruviana, Trachelospermum lucidum, Alstonia scholaris, and Catharanthus roseus demonstrated hypostomatic leaves. Nearly all the investigated species had anisocytic type of stomata only or in combination with other types of stomata on the upper and lower epidermis. Carissa carandas had anomocytic, anisocytic, and cyclocytic type of stomata on the upper epidermis, and the lower epidermis showed variations in stomatal type, such as anomocytic, stephanocytic, brachyparacytic, and hemiparacytic. Nerium oleander had no specific shape of stomata but showed stomatal crypts in which the stomata were enclosed inside many trichomes. The taxonomic key based on stomatal types, epidermal cells, stomatal index value, and statistical analysis, along with the variations in the epidermal cells, shows the link between the selected plants species, which will provide a baseline for future anatomical studies. This study highlights many undocumented micromorphological characteristics. The anatomical characteristics observed in this study will be helpful for taxonomic identification and species delimitation of the family Apocynaceae.


Assuntos
Apocynaceae/anatomia & histologia , Apocynaceae/classificação , Estômatos de Plantas/anatomia & histologia , Tricomas/anatomia & histologia , Células Epidérmicas/ultraestrutura , Microscopia , Microscopia Eletrônica de Varredura , Paquistão , Epiderme Vegetal/anatomia & histologia , Folhas de Planta/anatomia & histologia
16.
Microsc Res Tech ; 82(3): 250-259, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597704

RESUMO

Seed micromorphology of 13 species, belonging to four genera of subfamily Alsinoideae (Caryophyllaceae) were investigated with scanning electron microscopy (SEM), in order to assess their diagnostic significance at generic level and provide additional evidence on species delimitation, as well as correct identification and phylogenetic position. Genera and species of subfamily Alsinoideae exhibit great variation in ultrastructure and a high diversity of novel micromorphological characters were observed. Variation in seed shape, color, hilum, anticlinal wall, epidermal cell, cell surface, margins, and quantitative characters as length and width were studied in detail, compared, illustrated, and their taxonomic significant were discussed. Seed shapes of the species were classified as reniform, round, angular, subcircular, subreniform, and elliptical pyriform, with sub-central, central, basal, and nearly basal hilum. Wavy, irregular, tetragonal, and elongated epidermal cells structure has been observed as an exomorphological character. The present findings show that the micromorphology of subfamily Alsinoideae provides taxonomic information and is helpful to distinguish different species. The results also explained that SEM morphology of seeds provide important data about affinity among taxa and give potential characters in delimitation of members of subfamily Alsinoideae at generic and species level. A principal component analysis allowed to highlight the most outsiders among seed micromorphology with a possible explanation. Taxonomic keys were developed based on micromorphological characters to delimit the species and useful for their quick identification within subfamily Alsinoideae.


Assuntos
Caryophyllaceae/anatomia & histologia , Caryophyllaceae/classificação , Sementes/ultraestrutura , Microscopia Eletrônica de Varredura , Filogenia , Análise de Componente Principal , Sementes/anatomia & histologia
17.
Microsc Res Tech ; 82(4): 352-360, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30575183

RESUMO

In this study, comparative morphology, foliar anatomy and palynology of Spergula fallax and Spergula arvensis (Caryophyllaceae) were studied using multiple microscopic techniques. Genus Spergula includes worldwide five species, while in Flora of Pakistan the genus has two species. In this research, the comparative morphological, anatomical, and palynological characters of the two Pakistani Spergula species were studied. We examined some distinguishing morphological features, in both species, such as plant size, habitat, leaf morphological characters, inflorescences, flowers outer whorls, sepals and petals, and flowers number. These characters species were studied analyzing their comparative systematic significant. The foliar anatomical features also provided distinctive characters as the epidermal cell shape, the wall of the epidermal cell, lobes per cell. The differences in quantitative characters were also examined. The palynological characters showed difference in echini arrangement, echini density, and numbers of pore. Quantitative characters were variations in size of polar, equatorial, exine thickness, pore length, and width and P/E ratio. The multiple microscopic techniques provided sufficient evidence about the systematics of the genus Spergula. Based on morphological, anatomical, and palynological characters, analytical keys were developed for the identification and distinction of the species S. fallax and S. arvensis.


Assuntos
Caryophyllaceae/anatomia & histologia , Flores/anatomia & histologia , Epiderme Vegetal/ultraestrutura , Folhas de Planta/anatomia & histologia , Pólen/ultraestrutura , Caryophyllaceae/classificação , Microscopia Eletrônica de Varredura , Paquistão
18.
Microsc Res Tech ; 82(3): 317-332, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30582243

RESUMO

The present study is insights into foliar epidermal anatomy for characterizing clades, and their utility in taxonomic segregation of certain species of Pteridaceae from Northern Pakistan. The leaf epidermal anatomy of 10 species of Pteridaceae representing four genera were examined using light and scanning electron microscope. A micromorphological matrix was constructed for eight qualitative and 12 quantitative characters. unweighted pair group method with arithmetic means and principal components analysis statistical analysis were performed to test the validity of foliar epidermal anatomical features as method of separating species and genera, and phylogenetic clusters among species are constructed using qualitative and quantitative traits. The qualitative characters described here are shape of epidermal cells, stomata, guard cell and subsidiary cells, anticlinal wall pattern, and trichomes types which is helpful in defining groups within Pteridaceae. In addition, the size of stomata, guard cells, subsidiary cells, stomatal pore epidermal cells, and trichomes are quantitatively analyzed. All species have hypostomatic leaves. Two types of stomata were observed in studied species, anomocytic and polocytic. Anomocytic stomata were observed in three genera namely: Adiantum, Onychium, and Chielanthes whereas Pteris can be discriminated from other genera by its polocytic stomata. On the basis of multivariate analysis present study does provides sufficient information on the taxonomic importance of foliar anatomy which validate its efficacy in species and genera discrimination. From result obtained here it is further possible to use leaf micromorphologic data in ferns phylogeny and providing basis for future taxonomic delimitation in other taxa.


Assuntos
Folhas de Planta/anatomia & histologia , Estômatos de Plantas/anatomia & histologia , Pteridaceae/anatomia & histologia , Pteridaceae/classificação , Tricomas/anatomia & histologia , Microscopia Eletrônica de Varredura , Paquistão , Epiderme Vegetal/anatomia & histologia , Epiderme Vegetal/citologia , Análise de Componente Principal
19.
Int J Biol Macromol ; 106: 569-578, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28834706

RESUMO

Flavonoids, a class of polyphenols are known to be effective inducers of apoptosis and cytotoxicity in cancer cells. It is believed that antioxidant activity of polyphenols cannot fully account for induction of apoptosis and chemotherapeutic prevention in various cancers. In this article, by employing single cell alkaline gel electrophoresis (comet assay), we established that antioxidants, flavonoids such as (myricetin=MN, fisetin=FN, quercetin=QN, kaempferol=KL and galangin=GN) can cause cellular DNA breakage, also act as pro-oxidant in presence of transition metal ion such as copper. It was observed that the extent of cellular DNA breakage was found significantly higher in presence of copper. Hydroxyl radicals are generated as a sign of flavonoids' pro-oxidant nature through redox recycling of copper ions. Further, a dose-dependent inhibition of proliferation of breast cancer cells MDA-MB-231 by MN was found leading to pro-oxidant cell death, as assessed by MTT assay. Since levels of copper are considerably elevated in tissue, cell and serum during various malignancies, suggesting that cancer cells would be more subject to copper induced oxidative DNA breakage. Such a copper dependent pro-oxidant cytotoxic mechanism better explains the anticancer activity and preferential cytotoxicity of dietary phytochemicals against cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cobre/farmacologia , Células Epiteliais/efeitos dos fármacos , Flavonoides/farmacologia , Oxidantes/farmacologia , Espécies Reativas de Oxigênio/agonistas , Apoptose/efeitos dos fármacos , Cátions Bivalentes , Linhagem Celular Tumoral , Cobre/química , Dano ao DNA , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Flavonóis , Humanos , Quempferóis/farmacologia , Oxirredução , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo
20.
J Biomol Struct Dyn ; 36(14): 3791-3802, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29143574

RESUMO

Several mammalian proteins form pathological deposits under nonphysiological conditions that are associated with many degenerative diseases. Protein aggregation is associated with aging, as well as a variety of diseases, including cystic fibrosis, amyotrophic lateral sclerosis (ALS), and hypertrophic cardiomyopathy. There is a lack of any potential anti-amyloidogenic agents and therapeutics till date. Polyphenols have been accredited with myriad biological effects. An analysis of the effects of natural agents like baicalin (BC) and gallocatechin (GC) on aggregation process can open new avenues for the treatment of protein misfolding diseases. Thus, investigation of the effects of these flavonoids on Buffalo Heart Cystatin (BHC) aggregation induced by a reactive metabolic dialdehyde, glyoxal (GO), was taken up. Results have shown that elevated concentration of GO forms aggregates of BHC, which was characterized by an increase in the ANS fluorescence intensity, an increase in ThT fluorescence intensity, red shift in Congo red absorbance, negative ellipticity peak at 217 nm in the far-UVCD and BHC aggregates displaying by TEM. Using fluorescence spectroscopic analysis with Thioflavin T, CD and electron microscopic studies, anti-aggregation effects of polyphenols, BC and GC were analyzed. The study showed that BC and GC produced concentration-dependent anti-aggregation effects with GC producing a more pronounced effect than BC. The study proposed a mechanistic approach assuming structural constraints and specific aromatic interactions of polyphenols with sheets of BHC aggregates.


Assuntos
Catequina/análogos & derivados , Cistatinas/química , Flavonoides/química , Glioxal/química , Animais , Catequina/química , Catequina/farmacologia , Bovinos , Cistatinas/metabolismo , Flavonoides/farmacologia , Estrutura Molecular , Agregados Proteicos/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Análise Espectral , Relação Estrutura-Atividade
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