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1.
Am J Hum Genet ; 108(7): 1330-1341, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34102099

RESUMEN

Adaptor protein (AP) complexes mediate selective intracellular vesicular trafficking and polarized localization of somatodendritic proteins in neurons. Disease-causing alleles of various subunits of AP complexes have been implicated in several heritable human disorders, including intellectual disabilities (IDs). Here, we report two bi-allelic (c.737C>A [p.Pro246His] and c.1105A>G [p.Met369Val]) and eight de novo heterozygous variants (c.44G>A [p.Arg15Gln], c.103C>T [p.Arg35Trp], c.104G>A [p.Arg35Gln], c.229delC [p.Gln77Lys∗11], c.399_400del [p.Glu133Aspfs∗37], c.747G>T [p.Gln249His], c.928-2A>C [p.?], and c.2459C>G [p.Pro820Arg]) in AP1G1, encoding gamma-1 subunit of adaptor-related protein complex 1 (AP1γ1), associated with a neurodevelopmental disorder (NDD) characterized by mild to severe ID, epilepsy, and developmental delay in eleven families from different ethnicities. The AP1γ1-mediated adaptor complex is essential for the formation of clathrin-coated intracellular vesicles. In silico analysis and 3D protein modeling simulation predicted alteration of AP1γ1 protein folding for missense variants, which was consistent with the observed altered AP1γ1 levels in heterologous cells. Functional studies of the recessively inherited missense variants revealed no apparent impact on the interaction of AP1γ1 with other subunits of the AP-1 complex but rather showed to affect the endosome recycling pathway. Knocking out ap1g1 in zebrafish leads to severe morphological defect and lethality, which was significantly rescued by injection of wild-type AP1G1 mRNA and not by transcripts encoding the missense variants. Furthermore, microinjection of mRNAs with de novo missense variants in wild-type zebrafish resulted in severe developmental abnormalities and increased lethality. We conclude that de novo and bi-allelic variants in AP1G1 are associated with neurodevelopmental disorder in diverse populations.


Asunto(s)
Complejo 1 de Proteína Adaptadora/genética , Discapacidades del Desarrollo/genética , Epilepsia/genética , Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , Alelos , Animales , Análisis Mutacional de ADN , Femenino , Células HEK293 , Humanos , Masculino , Linaje , Ratas , Pez Cebra/genética
2.
J Pak Med Assoc ; 71(7): 1897-1899, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34410270

RESUMEN

Chondromyxoid fibroma is a rare tumour, representing <1% of all primary bone neoplasm. We report the case of a four-year-old female child with a one-year history of nasal obstruction and facial swelling. A large enhanced lesion with amorphous densities spreading into the right cribriform plate and floor of sphenoid sinus, laterally into the right lamina papyracea, inferolaterally into the medial wall of maxillary sinus, posteriorly into the nasopharynx and superior aspect of oropharynx was observed on CT scan. The mass was excised by Caldwell Luc's endoscopic medial maxillectomy via sublabial approach. CMF was confirmed histopathologically.


Asunto(s)
Neoplasias Óseas , Fibroma , Niño , Preescolar , Endoscopía , Femenino , Fibroma/diagnóstico por imagen , Fibroma/cirugía , Humanos , Tomografía Computarizada por Rayos X
3.
Molecules ; 25(4)2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32079172

RESUMEN

Proteins are among the most important molecules on Earth. Their structure and aggregation behavior are key to their functionality in living organisms and in protein-rich products. Innovations, such as increased computer size and power, together with novel simulation tools have improved our understanding of protein structure-function relationships. This review focuses on various proteins present in plants and modeling tools that can be applied to better understand protein structures and their relationship to functionality, with particular emphasis on plant storage proteins. Modeling of plant proteins is increasing, but less than 9% of deposits in the Research Collaboratory for Structural Bioinformatics Protein Data Bank come from plant proteins. Although, similar tools are applied as in other proteins, modeling of plant proteins is lagging behind and innovative methods are rarely used. Molecular dynamics and molecular docking are commonly used to evaluate differences in forms or mutants, and the impact on functionality. Modeling tools have also been used to describe the photosynthetic machinery and its electron transfer reactions. Storage proteins, especially in large and intrinsically disordered prolamins and glutelins, have been significantly less well-described using modeling. These proteins aggregate during processing and form large polymers that correlate with functionality. The resulting structure-function relationships are important for processed storage proteins, so modeling and simulation studies, using up-to-date models, algorithms, and computer tools are essential for obtaining a better understanding of these relationships.


Asunto(s)
Modelos Moleculares , Proteínas de Almacenamiento de Semillas/química , Proteínas de Almacenamiento de Semillas/metabolismo , Alimentos , Industrias , Relación Estructura-Actividad
4.
Int J Biol Macromol ; 267(Pt 1): 131402, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582462

RESUMEN

This study investigates how wheat gluten (WG) films in the presence of salicylic acid are influenced by thermal pretreatment. Unlike previous methods conducted at low moisture content, our procedure involves pretreating WG at different temperatures (65 °C, 75 °C, and 85 °C), in a solution with salicylic acid. This pretreatment aims to enhance protein unfolding, thus providing more opportunities for protein-protein interactions during the subsequent solvent casting into films. A significant increase in ß-sheet structures was observed in FTIR spectra of samples pretreated at 75 °C and 85 °C, showing a prominent peak in the range of 1630-1640 cm-1. The pretreatment at 85 °C was found to be effective in improving the water resistivity of the films by up to 247 %. Moreover, it led to a significant enhancement of 151 % in tensile strength and a 45 % increase in the elastic modulus. The reduced solubility observed in films derived from pretreated WG suggests the development of an intricate protein network arising from protein-protein interactions during the pretreatment and film formation. Thermal pretreatment at 85 °C significantly enhances the structural and mechanical properties of WG films, including improved water resistivity, tensile strength, and intricate protein network formation.


Asunto(s)
Glútenes , Calor , Ácido Salicílico , Resistencia a la Tracción , Ácido Salicílico/química , Glútenes/química , Solubilidad , Agua/química , Triticum/química , Espectroscopía Infrarroja por Transformada de Fourier
5.
Microsc Res Tech ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38798148

RESUMEN

The preparation of ethylenediaminetetraacetic acid (EDTA) functionalized pine needles biochar (EDTA@BC) as a low-cost active adsorbent and its effectiveness in removing Ni(II) from aqueous solution at various conditions is reported in this paper. First, alkali activation was selected to render the pine needle biochar with an excellent porous structure and increased concentration of hydroxyl groups to facilitate grafting. Subsequently, a simple method was utilized to graft EDTA onto the biochar. The prepared EDTA@BC was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive x-ray spectrometry (EDX). Batch adsorption studies were conducted to assess the impact of various parameters such as solution pH, adsorbent dosage, adsorbate volume, and shaking time on the removal efficiency of Ni(II). At pH 6, 100 mg dosage, 4 mL of adsorbate volume, and 10 min of shaking time, the maximum removal efficiency of Ni(II) was observed to be 89%. EDTA@BC showed reasonable sorption performance still after the third cycle of regeneration. The effect of interfering ions such as Pb, Cr, Cu, and Hg was evaluated, resulting a decrease of 69%, 78%, 76%, and 68%, respectively, in its sorption capacity. The Langmuir model provided a better fit for Ni(II) in the concentration range of 0.1-2000 ppm under optimized conditions, with qmax of 46.69 ± 1.031 mg/g and KL of 0.001, compared with the Freundlich isotherm, which yielded n = 0.234 and χ2 = 2.7899, Temkin isotherm (R2 = 0.9520), and Redlich-Peterson isotherm (R2 = 0.9725). The removal of Ni(II) by EDTA@BC was found to be the pseudo-second-order kinetics. Thermodynamic studies indicated adsorption process to be endothermic and nonspontaneous. Hence, a sustainable valorized bio-material (EDTA@BC) is prepared having better sorption efficiency of Ni(II) from aqueous solution with possible wide applicability. RESEARCH HIGHLIGHTS: New EDTA functionalized indigenous pine needles biochar (EDTA@BC) was prepared. This low-cost active adsorbent found effective in removing Ni(II) from aqueous solution. FTIR, SEM, and EDX proved synthesis and uptake of Ni(II) from aqueous solution. Ni(II) removal, regeneration, interfering and adsorption studies were performed by UV-Vis spectroscopy.

6.
Bioengineering (Basel) ; 10(7)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37508800

RESUMEN

The aim of this review article is to appraise the design and functionality of above-knee prosthetic legs. So far, various transfemoral prosthetic legs are found to offer a stable gait to amputees but are limited to laboratories. The commercially available prosthetic legs are not reliable and comfortable enough to satisfy amputees. There is a dire need for creating a powered prosthetic knee joint that could address amputees' requirements. To pinpoint the gap in transfemoral prosthetic legs, prosthetic knee unit model designs, control frameworks, kinematics, and gait evaluations are concentrated. Ambulation exercises, ground-level walking, running, and slope walking are considered to help identify research gaps and areas where existing prostheses can be ameliorated. The results show that above-knee amputees can more effectively manage their issues with the aid of an active prosthesis, capable of reliable gait. To accomplish the necessary control, closed loop controllers and volitional control are integral parts. Future studies should consider designing a transfemoral electromechanical prosthesis based on electromyographic (EMG) signals to better predict the amputee's intent and control in accordance with that intent.

7.
Int J Biol Macromol ; 211: 592-615, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35577195

RESUMEN

Our aim was to understand mechanisms for clustering and cross-linking of gliadins, a wheat seed storage protein type, monomeric in native state, but incorporated in network while processed. The mechanisms were studied utilizing spectroscopy and high-performance liquid chromatography on a gliadin-rich fraction, in vitro produced α-gliadins, and synthetic gliadin peptides, and by coarse-grained modelling, Monte Carlo simulations and prediction algorithms. In solution, gliadins with α-helix structures (dip at 205 nm in CD) were primarily present as monomeric molecules and clusters of gliadins (peaks at 650- and 700-s on SE-HPLC). At drying, large polymers (Rg 90.3 nm by DLS) were formed and ß-sheets increased (14% by FTIR). Trained algorithms predicted aggregation areas at amino acids 115-140, 150-179, and 250-268, and induction of liquid-liquid phase separation at P- and Poly-Q-sequences (Score = 1). Simulations showed that gliadins formed polymers by tail-to-tail or a hydrophobic core (Kratky plots and Ree = 35 and 60 for C- and N-terminal). Thus, the N-terminal formed clusters while the C-terminal formed aggregates by disulphide and lanthionine bonds, with favoured hydrophobic clustering of similar/exact peptide sections (synthetic peptide mixtures on SE-HPLC). Mechanisms of clustering and cross-linking of the gliadins presented here, contribute ability to tailor processing results, using these proteins.


Asunto(s)
Gliadina , Triticum , Análisis por Conglomerados , Gliadina/química , Péptidos/metabolismo , Polímeros/metabolismo , Triticum/química
8.
Eur J Hum Genet ; 30(2): 243-247, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34750527

RESUMEN

Intellectual disability (ID) represents an extremely heterogeneous group of disorders, characterized by significant limitations in intellectual function and adaptive behavior. Among the monogenic causes, autosomal recessive genes (ARID) are responsible for more than 50% of ID. Here, we report a novel in-frame homozygous deletion variant [c.730_753del; p.(Ala244_Gly251del)] in SOX4 (sex-determining region Y-related high-mobility group box 4), segregating with moderate to severe ID, hypotonia, and developmental delay in a Pakistani family. Our identified variant p.(Ala244_Gly251del) is predicted to remove evolutionarily conserved residues from the interdomain region and may destabilize the protein secondary structure. SOX4 belongs to group C of the SOX transcription regulating family known to be involved in early embryo development. Single-cell RNA data analysis of developing telencephalon revealed highly overlapping expression of SOX4 with SOX11 and DCX, known neurogenesis regulators. Our study expands the mutational landscape of SOX4 and the repertoire of the known genetic causes of ARID.


Asunto(s)
Discapacidad Intelectual , Genes Recesivos , Homocigoto , Humanos , Discapacidad Intelectual/genética , Hipotonía Muscular/genética , Pakistán , Factores de Transcripción SOXC/genética , Eliminación de Secuencia
9.
Biomolecules ; 10(8)2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32717949

RESUMEN

Gluten protein crosslinking is a predetermined process where specific intra- and intermolecular disulfide bonds differ depending on the protein and cysteine motif. In this article, all-atom Monte Carlo simulations were used to understand the formation of disulfide bonds in gliadins and low molecular weight glutenin subunits (LMW-GS). The two intrinsically disordered proteins appeared to contain mostly turns and loops and showed "self-avoiding walk" behavior in water. Cysteine residues involved in intramolecular disulfide bonds were located next to hydrophobic peptide sections in the primary sequence. Hydrophobicity of neighboring peptide sections, synthesis chronology, and amino acid chain flexibility were identified as important factors in securing the specificity of intramolecular disulfide bonds formed directly after synthesis. The two LMW-GS cysteine residues that form intermolecular disulfide bonds were positioned next to peptide sections of lower hydrophobicity, and these cysteine residues are more exposed to the cytosolic conditions, which influence the crosslinking behavior. In addition, coarse-grained Monte Carlo simulations revealed that the protein folding is independent of ionic strength. The potential molecular behavior associated with disulfide bonds, as reported here, increases the biological understanding of seed storage protein function and provides opportunities to tailor their functional properties for different applications.


Asunto(s)
Disulfuros/química , Gliadina/química , Glútenes/química , Proteínas Intrínsecamente Desordenadas/química , Método de Montecarlo , Cisteína/química , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Peso Molecular , Pliegue de Proteína , Estructura Secundaria de Proteína
10.
Sci Rep ; 10(1): 8884, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32483287

RESUMEN

Capparis spinosa is an edible medicinal plant which is considered as an excellent source of rutin. Rutin is a glycoside of the flavonoid quercetin that has been reported to have a beneficial role in controlling various diseases such as hypertension, arteriosclerosis, diabetes, and obesity. In this study, the partial cDNA of four genes involved in the rutin biosynthetic pathway including 4-coumaroyl CoA ligase (4CL), flavonoid 3'-hydroxylase (F3'H), flavonol synthase (FLS) and flavonol-3-O-glucoside L-rhamnosyltransferase (RT) were identified in C.spinosa plants for the first time. The protein sequences of these genes shared high similarity with the same proteins in other plant species. Subsequently, the expression patterns of these genes as well as rutin accumulation in C.spinosa leaves treated with different concentrations of salicylic acid (SA) and methyl jasmonate (MeJA) and also in different tissues of Caper plants treated with 100 mgL-1 SA and 150 µM MeJA were evaluated. The expression of all four genes was clearly up-regulated and rutin contents increased in response to MeJA and SA treatments after 24 h. The highest rutin contents (5.30 mgg-1 DW and 13.27 mgg-1 DW), as well as the highest expression levels of all four genes, were obtained using 100 mgL-1 SA and 150 µM MeJA, respectively. Among the different tissues, the highest rutin content was observed in young leaves treated with 150 µM MeJA, which corresponded to the expression of related genes, especially RT, as a key gene in the rutin biosynthetic pathway. These results suggest that rutin content in various tissues of C. spinosa can be enhanced to a significant extent by MeJA and SA treatments and the gene expression patterns of rutin-biosynthesis-related genes are regulated by these elicitors.


Asunto(s)
Vías Biosintéticas/efectos de los fármacos , Capparis/crecimiento & desarrollo , Perfilación de la Expresión Génica/métodos , Reguladores del Crecimiento de las Plantas/farmacología , Rutina/biosíntesis , Acetatos/farmacología , Secuencia de Aminoácidos , Capparis/efectos de los fármacos , Capparis/genética , Capparis/metabolismo , Ciclopentanos/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Especificidad de Órganos , Oxilipinas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Ácido Salicílico/farmacología , Regulación hacia Arriba
11.
BMC Complement Med Ther ; 20(1): 293, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-32993632

RESUMEN

BACKGROUND: Diabetes mellitus is a chronic disease characterized by hyperglycemia that may occur due to genetic, environmental or lifestyle factors. Natural remedies have been used to treat diabetes since long and many antidiabetic compounds of varied efficacies have been isolated from medicinal plants. Rhazya stricta has been used for decades for the treatment of diabetes mellitus and associated ailments. Considering the folkloric use of R. stricta against diabetes, it was aimed to investigate the effectiveness of its root extracts against diabetes through in vitro assays and in vivo studies using animal model along with phytochemical profiling through GCMS. METHODS: Various fractions of Rhazya stricta obtained through column chromatography were evaluated for a variety of assays including α-glucosidase, Dipeptidyl peptidase-IV (DPP-IV), ß-secretase and Glucagon-like peptide-1 (GLP-1) secretion studies. For the in vivo studies the alloxan-induced diabetic mice were treated with root extracts and blood glucose levels, HbA1C, and other biochemical markers along with the histological study of the liver were done. The phytochemical identification was performed using an Agilent 7890B GC coupled to a 7010 Triple Quadrupole (MS/MS) system. GraphPad Prism software version 5.01 was used for statistical analysis. RESULTS: Majority of the extract fractions showed excellent results against diabetes by inhibiting enzymes DPP-IV (Up to 61%) and ß-secretase (Up to 83%) with IC50s 979 µg/ml and 169 µg/ml respectively with increase in the GLP1 secretion. The results of in vivo studies indicated a marked reduction in blood glucose and HbA1c levels along with positive effects on other parameters like lipid profile, liver functions and renal functions of extract-treated mice as compared to control. The histological examination of the liver demonstrated hepatoprotective effects against diabetes led changes and various classes of phytochemicals were also identified through GCMS in different fractions. CONCLUSION: The results revealed strong antidiabetic activity of R. stricta root with the potential to protect body organs against diabetic changes. Moreover, a variety of phytochemicals has also been identified through GCMS that might be responsible for the antidiabetic potential of Rhazya stricta root.


Asunto(s)
Apocynaceae , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Aloxano , Animales , Masculino , Ratones , Ratones Endogámicos BALB C , Pakistán , Raíces de Plantas
12.
Cureus ; 10(9): e3351, 2018 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-30483456

RESUMEN

Variegate porphyria (VP) is one of the groups of rare inherited disorders of hemoglobin synthesis called Porphyria. It has two distinct manifestations, that is, those of cutaneous and nervous system. Posterior reversible encephalopathy syndrome (PRES) is a rare complication of porphyria. It occurs due to vasogenic edema in white matter of predominantly parieto-occipital lobes, characterized by headache, visual disturbances, altered mental state, hypertension, and seizures. We report a child diagnosed with VP who presents with clinical signs and radiological manifestations suggestive of PRES. To our knowledge this has never been reported in a case of VP and only twice been reported in another type of porphyria. A 12-year-old pre-pubertal boy already diagnosed with VP presents with seizure, visual disturbance, altered mental status, headache, and hypertension. Initial brain magnetic resonance imaging (MRI) revealed bilateral increased signal intensity in parieto-occipital region. Neurological opinion suggested that the symptoms experienced by the patient seem to be a complication of porphyria. Treatment was to control hypertension and prevent use of any aggravating agents. Follow-up MRI after two weeks revealed interval reduction in disease process. Diagnosis of PRES was thus confirmed. PRES should be considered in patients presenting with symptoms typical of encephalitis/meningitis/acute disseminated encephalomyelitis in a patient suffering from porphyria. Early diagnosis is key to quick improvement and prevention of complications. Though rare in pre-pubertal patients, it should be kept as a possibility especially when patients present with hypertension. Care should be taken to not use any drugs that can trigger PRES.

13.
ACS Omega ; 3(5): 5584-5592, 2018 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-30023922

RESUMEN

A combination of genotype, cultivation environment, and protein separation procedure was used to modify the nanoscale morphology, polymerization, and chemical structure of glutenin proteins from wheat. A low-polymerized glutenin starting material was the key to protein-protein interactions mainly via SS cross-links during film formation, resulting in extended ß-sheet structures and propensity toward the formation of nanoscale morphologies at molecular level. The properties of glutenin bioplastic films were enhanced by the selection of a genotype with a high number of cysteine residues in its chemical structure and cultivation environment with a short grain maturation period, both contributing positively to gluten strength. Thus, a combination of factors affected the structure of glutenins in bioplastic films by forming crystalline ß-sheets and propensity toward the ordered nanostructures, thereby resulting in functional properties with high strength, stiffness, and extensibility.

14.
Int J Surg Pathol ; 24(1): 55-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26316051

RESUMEN

Mixed tumors composed of schwannoma and meningioma are extremely rare and are usually associated with neurofibromatosis type 2. So far, all the cases reported have involved the cerebellopontine angle. Only 3 reported cases did not have a clear association with neurofibromatosis type 2. We report a mixed tumor comprising schwannoma admixed with meningioma and ependymoma in the cervical spinal cord of a 22-year-old male.


Asunto(s)
Ependimoma/patología , Neoplasias Meníngeas/patología , Meningioma/patología , Neoplasias Primarias Múltiples/patología , Neurilemoma/patología , Neoplasias de la Médula Espinal/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
15.
Int J Biol Macromol ; 79: 151-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25936284

RESUMEN

Protein macromolecules adopted for biological and bio-based material functions are known to develop a structured protein network upon chemical modification. In this study, we aimed to evaluate the impact of chemical additives such as, NaOH, NH4OH and salicylic acid (SA), on the secondary and nano-structural transitions of wheat proteins. Further, the effect of chemically induced modifications in protein macromolecular structure was anticipated in relation to functional properties. The gliadin-NH4OH-SA film showed a supramolecular protein organization into hexagonal structures with 65 Å lattice parameter, and other not previously observed structural entities having a characteristic distance of 50 Å. Proteins in gliadin-NH4OH-SA films were highly polymerized, with increased amount of disulfide crosslinks and ß-sheets, causing improved strength and stiffness. Glutenin and WG proteins with NH4OH-SA showed extensive aggregation and an increase in ß-sheet content together with irreversible crosslinks. Irreversible crosslinks hindered a high order structure formation in glutenins, and this resulted in films with only moderately improved stiffness. Thus, formation of nano-hierarchical structures based on ß-sheets and disulfide crosslinks are the major reasons of high strength and stiffness in wheat protein based films.


Asunto(s)
Gliadina/química , Glútenes/química , Membranas Artificiales , Nanoestructuras/química , Triticum/química , Hidróxido de Amonio/química , Disulfuros/química , Gliadina/aislamiento & purificación , Glútenes/aislamiento & purificación , Polimerizacion , Agregado de Proteínas , Estructura Secundaria de Proteína , Ácido Salicílico/química , Hidróxido de Sodio/química , Resistencia a la Tracción
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