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1.
Inorg Chem ; 63(7): 3486-3498, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38329939

RESUMO

An exceptional Zinc(II)-organic framework with the formula [{Zn(L4-py)(bdc)}·DMF]n (Zn-MOF) has been constructed solvothermally using a novel linker L4-py {2,7-bis(3-(pyridin-4-ylethynyl)phenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone}, coligand H2bdc (1,4-benzenedicarboxylic acid), and ZnBF4·xH2O. The ligand L4-py has been fabricated after functionalization of NDA (1,4,5,8-naphthalenetetracarboxylic dianhydride) core with 3-(pyridin-4-ylethynyl)phenyl group. The single-crystal X-ray analysis reveals that Zn-MOF exhibits a comprehensive three-dimensional (3D) framework architecture and features (4)-connected uninodal dia; 4/6/c1; sqc6 topology with point symbol {66} and two-dimensional (2D) + 2D, parallel polycatenation. Notably, Zn-MOF displayed excellent fluorescence phenomenon and stability in water as well as in methanol solvents and was harnessed as a versatile sensor, demonstrating selective and sensitive molecular recognition of flame retardants and antibiotics. Notably, Zn-MOF displayed 57 and 49.5% quenching efficiency for the flame-retardant pentabromophenol (PBP) and 3,3',5,5'-tetrabromobisphenol A (TBPA), respectively. Whereas an outstanding 90% quenching efficiency was observed for antibiotics, tetracycline (TC) and secnidazole (SD). The mechanistic investigations of this luminescence quenching suggest that this might be primarily occurring via the Fourier resonance energy transfer (FRET) and photoinduced electron transfer (PET) mechanisms, which might be assisted by the competitive absorption and host-guest interactions. The π-electron-rich framework structure of sensor Zn-MOF activates this mechanism.

2.
Empir Softw Eng ; 29(5): 115, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39069997

RESUMO

Context: Researchers testing hypotheses related to factors leading to low-quality software often rely on historical data, specifically on details regarding when defects were introduced into a codebase of interest. The prevailing techniques to determine the introduction of defects revolve around variants of the SZZ algorithm. This algorithm leverages information on the lines modified during a bug-fixing commit and finds when these lines were last modified, thereby identifying bug-introducing commits. Objectives: Despite several improvements and variants, SZZ struggles with accuracy, especially in cases of unrelated modifications or that touch files not involved in the introduction of the bug in the version control systems (aka tangled commit and ghost commits). Methods: Our research investigates whether and how incorporating content retrieved from bug discussions can address these issues by identifying the related and external files and thus improve the efficacy of the SZZ algorithm. Results: To conduct our investigation, we take advantage of the links manually inserted by Mozilla developers in bug reports to signal which commits inserted bugs. Thus, we prepared the dataset, RoTEB, comprised of 12,472 bug reports. We first manually inspect a sample of 369 bug reports related to these bug-fixing or bug-introducing commits and investigate whether the files mentioned in these reports could be useful for SZZ. After we found evidence that the mentioned files are relevant, we augment SZZ with this information, using different strategies, and evaluate the resulting approach against multiple SZZ variations. Conclusion: We define a taxonomy outlining the rationale behind developers' references to diverse files in their discussions. We observe that bug discussions often mention files relevant to enhancing the SZZ algorithm's efficacy. Then, we verify that integrating these file references augments the precision of SZZ in pinpointing bug-introducing commits. Yet, it does not markedly influence recall. These results deepen our comprehension of the usefulness of bug discussions for SZZ. Future work can leverage our dataset and explore other techniques to further address the problem of tangled commits and ghost commits. Data & material: https://zenodo.org/records/11484723.

3.
Inorg Chem ; 61(18): 6977-6994, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35481354

RESUMO

Synthesis and structural depiction of two new metal-organic frameworks (MOFs), namely, [{Zn(L)(oba)}·4H2O]α (Zn-MOF-1) and [{Cd1/2(L)1/2(nipa)1/2(H2O)1/2}·(DMF)1/2(H2O)]α (Cd-MOF-2) (where L = N2,N6-di(pyridin-4-yl)naphthalene-2,6-dicarboxamide, 4,4'-H2oba = 4,4'-oxybisbenzoic acid, and 5-H2nipa = 5-nitroisophthalic acid) are reported. Both Zn-MOF-1 and Cd-MOF-2 have been prepared by reacting ligand L and coligand 4,4'-H2oba or 5-H2nipa with the respective dihydrates of Zn(OAc)2 and Cd(OAc)2 (OAc = acetate). Crystal structure X-ray analysis discloses that Zn-MOF-1 displays an overall 2D → 3D interpenetrated framework structure. The topological analysis by ToposPro suggests a (4)-connected uninodal sql topology with a point symbol of {44·62} having 2D + 2D parallel polycatenation. However, crystal packing of Cd-MOF-2 adapted a porous framework architecture and was topologically simplified as (3,4)-connected binodal 2D net. In addition, both Zn-MOF-1 and Cd-MOF-2 were proved to be multifunctional materials for the recognition of organic amines and in the fixation of CO2 to cyclic carbonates. Remarkably, Zn-MOF-1 and Cd-MOF-2 showed very good fluorescence stability in aqueous media and have shown 98 and 97% quenching efficiencies, respectively, for 4-aminobenzoic acid (4-ABA), among all of the researched amines. The mechanistic study of organic amines recognition proposed that fluorescence quenching happened mainly through hydrogen-bonding and π-π stacking interactions. Additionally, cycloaddition of CO2 to epoxide in the presence of Zn-MOF-1 and Cd-MOF-2 afforded up to 96% of cyclic carbonate within 24 h. Both Zn-MOF-1 and Cd-MOF-2 exhibited recyclability for up to five cycles without noticing an appreciable loss in their sensing or catalytic efficiency.

4.
J Fluoresc ; 32(1): 359-367, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34851472

RESUMO

A simple synchronous fluorescent chemosensor 3-hydroxy-2-(4-methoxyphenyl)-4H-chromen-4-one (3-HC) has been synthesized for the selective analysis of Al3+. On the addition of Al3+, 3-HC displayed a redshift with a change in wavelength of emission maximum from 436 to 465 nm along with enhancement in fluorescence intensity, which formed the basis for its sensitive detection. Under optimized conditions, 3-HC was applied for the determination of Al3+ in the concentration range of 1 × 10-7-1 × 10-6 M. The limit of detection (LOD) and limit of quantification (LOQ) values were found out to be 1.69 × 10-8 and 5.07 × 10-8 M respectively. Further, the developed method was applied for the analysis of Al3+ in real water samples (tap water, bottled water, and tube well water) which showed good recovery values in the range of 95-99.7% with RSD less than 4%.

5.
J Prosthet Dent ; 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36529546

RESUMO

STATEMENT OF PROBLEM: The conventional diagnostic mounting procedure in completely edentulous patients is time-consuming and increases the laboratory workload. Alternatives like optical scanners and jaw tracking devices have been documented but have their own shortcomings. PURPOSE: The purpose of this pilot clinical study was to assess the suitability of an infrared sensor scan device in procuring the diagnostic data parameters for completely edentulous patients. MATERIAL AND METHODS: Twelve completely edentulous participants were enrolled in the study. For each, the distance between the arches was measured by 2 clinical techniques at 3 common reference points, M1, M2, M3, for the maxillary arch and m1, m2, m3 for the mandibular arch. The control group measurements were recorded by using a standard diagnostic mounting procedure on a semi-adjustable articulator, and the experimental group measurements were recorded by using an infrared sensor scan device. To convert the analog infrared sensor output into digital data, the Arduino ADC software program was used. The data from both study groups were statistically compared by using the independent t test (α=.05). RESULTS: No significant difference in variation was found between the mean measurements of the device and diagnostic mounting (P>.05). The maximum variation recorded by the experimental device was 1.7 mm, whereas the minimum variation was 0.8 mm (mean 1.25 mm). CONCLUSIONS: The use of precisely calibrated infrared sensors may be a cost-effective option for diagnostic mounting.

6.
Sensors (Basel) ; 22(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35274628

RESUMO

The paper presents a new security aspect for a Mobile Ad-Hoc Network (MANET)-based IoT model using the concept of artificial intelligence. The Black Hole Attack (BHA) is considered one of the most affecting threats in the MANET in which the attacker node drops the entire data traffic and hence degrades the network performance. Therefore, it necessitates the designing of an algorithm that can protect the network from the BHA node. This article introduces Ad-hoc On-Demand Distance Vector (AODV), a new updated routing protocol that combines the advantages of the Artificial Bee Colony (ABC), Artificial Neural Network (ANN), and Support Vector Machine (SVM) techniques. The combination of the SVM with ANN is the novelty of the proposed model that helps to identify the attackers within the discovered route using the AODV routing mechanism. Here, the model is trained using ANN but the selection of training data is performed using the ABC fitness function followed by SVM. The role of ABC is to provide a better route for data transmission between the source and the destination node. The optimized route, suggested by ABC, is then passed to the SVM model along with the node's properties. Based on those properties ANN decides whether the node is a normal or an attacker node. The simulation analysis performed in MATLAB shows that the proposed work exhibits an improvement in terms of Packet Delivery Ratio (PDR), throughput, and delay. To validate the system efficiency, a comparative analysis is performed against the existing approaches such as Decision Tree and Random Forest that indicate that the utilization of the SVM with ANN is a beneficial step regarding the detection of BHA attackers in the MANET-based IoT networks.


Assuntos
Algoritmos , Inteligência Artificial , Simulação por Computador , Redes Neurais de Computação , Máquina de Vetores de Suporte
7.
J Contemp Dent Pract ; 22(6): 644-649, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34393121

RESUMO

AIM AND OBJECTIVE: This in vitro study evaluates and compares the changes in pulp chamber temperature during direct fabrication of provisional restorations in maxillary central incisors after using three different cooling techniques. MATERIALS AND METHODS: Total of 60 samples of maxillary central incisors along with their putty indices were divided into four groups (one control and three experimental) and were prepared using a surveyor cum milling machine. Teeth were sectioned 2 mm below cementoenamel junction and a K-type thermocouple wire was inserted in the tooth and secured at the pulpal roof using amalgam. Putty index filled with DPI tooth molding resin material [polymethyl methacrylate (PMMA)] was placed on the tooth and temperature changes per 5 seconds were recorded by temperature indicating device for the control, on-off, precooled putty, and dentin bonding agent (DBA) group. RESULTS: The highest mean obtained was of the control (11.04°C), followed by DBA group (9.53°C), precooled putty group (6.67°C), and on-off group (1.94°C). Precooled putty index group took maximum time to reach the baseline temperature (847.5 seconds). CONCLUSION: On-off technique is the most effective method to reduce the intrapulpal temperature during polymerization, as compared to the other techniques used in the study. Retardation in the polymerization process was seen in precooled putty group, which may make this technique clinically inadvisable. CLINICAL SIGNIFICANCE: Thermal protection of pulp must always be considered during direct fabrication of provisional restoration when a PMMA-based resin is used. By using on-off technique, not only the thermal insult to the pulp can be effectively minimized but also the harmful effects of residual monomer (poor marginal fit and pulpal irritation) can be eliminated.


Assuntos
Cavidade Pulpar , Polimetil Metacrilato , Materiais Dentários , Polpa Dentária , Restauração Dentária Temporária , Temperatura
8.
Antonie Van Leeuwenhoek ; 110(10): 1357-1371, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28831610

RESUMO

The current prokaryotic taxonomy classifies phenotypically and genotypically diverse microorganisms using a polyphasic approach. With advances in the next-generation sequencing technologies and computational tools for analysis of genomes, the traditional polyphasic method is complemented with genomic data to delineate and classify bacterial genera and species as an alternative to cumbersome and error-prone laboratory tests. This review discusses the applications of sequence-based tools and techniques for bacterial classification and provides a scheme for more robust and reproducible bacterial classification based on genomic data. The present review highlights promising tools and techniques such as ortho-Average Nucleotide Identity, Genome to Genome Distance Calculator and Multi Locus Sequence Analysis, which can be validly employed for characterizing novel microorganisms and assessing phylogenetic relationships. In addition, the review discusses the possibility of employing metagenomic data to assess the phylogenetic associations of uncultured microorganisms. Through this article, we present a review of genomic approaches that can be included in the scheme of taxonomy of bacteria and archaea based on computational and in silico advances to boost the credibility of taxonomic classification in this genomic era.


Assuntos
Archaea/classificação , Bactérias/classificação , Técnicas de Tipagem Bacteriana , Biologia Computacional , Genômica , Genoma Arqueal/genética , Genoma Bacteriano/genética , Metagenoma , Anotação de Sequência Molecular , Filogenia
9.
Indian J Microbiol ; 57(2): 155-161, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28611492

RESUMO

Pseudomonas fluorescens Pt14 is a non-pathogenic and acidophilic bacterium isolated from acidic soil (pH 4.65). Genome sequencing of strain Pt14 was performed using Single Molecule Real Time (SMRT) sequencing to get insights into unique existence of this strain in acidic environment. Complete genome sequence of this strain revealed a chromosome of 5,841,722 bp having 5354 CDSs and 88 RNAs. Phylogenomic reconstruction based on 16S rRNA gene, Average Nucleotide Identity (ANI) values and marker proteins revealed that strain Pt14 shared a common clade with P. fluorescens strain A506 and strain SS101. ANI value of strain Pt14 in relation to strain A506 was found 99.23% demonstrating a very close sub-species association at genome level. Further, orthology determination among these three phylogenetic neighbors revealed 4726 core proteins. Functional analysis elucidated significantly higher abundance of sulphur metabolism (>1×) which could be one of the reasons for the survival of strain Pt14 under acidic conditions (pH 4.65). Acidophilic bacteria have capability to oxidize sulphur into sulphuric acid which in turn can make the soil acidic and genome-wide analysis of P. fluorescens Pt14 demonstrated that this strain contributes towards making the soil acidic.

10.
Int J Syst Evol Microbiol ; 66(4): 1851-1856, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26869334

RESUMO

A Gram-stain-negative, aerobic, rod-shaped, non-spore-forming, yellow pigmented bacterial strain (UM1T) was isolated from the hexachlorocyclohexane (HCH)-contaminated dumpsite located at Ummari village in Lucknow, India. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain UM1T belongs to the genus Luteimonas with Luteimonas aestuarii B9T as the closest neighbour (97.2% 16S rRNA gene sequence similarity). The DNA G+C content of strain UM1T was 64.3 mol%. The major polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG). Main fatty acids were iso-C15:0, iso-C11:0, iso-C11:0 3-OH, iso-C17:0 and summed feature 9 (C16:0 10-methyl and/or iso-C17:1ω9c). Ubiquinone (Q-8) was the only respiratory quinone. Spermidine was detected as the major polyamine. The DNA-DNA relatedness value of strain UM1T with respect to its closest neighbour Luteimonas aestuarii B9T was well below 70 % (∼49%). Thus, data obtained from phylogenetic analysis, DNA-DNA hybridization, and chemotaxonomical and biochemical analyses supports classification of strain UM1T as representative of a novel species of the genus Luteimonas, for which the name Luteimonas tolerans sp. nov. is proposed. The type strain is UM1T (=DSM 28473T=MCC 2572T=KCTC 42936T).


Assuntos
Hexaclorocicloexano , Filogenia , Microbiologia do Solo , Poluentes do Solo , Xanthomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/química , Ubiquinona/química , Xanthomonadaceae/genética , Xanthomonadaceae/isolamento & purificação
11.
J Oral Maxillofac Surg ; 74(8): 1613-21, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27134156

RESUMO

PURPOSE: The aim of this study was to evaluate the long-term clinical and radiologic results of the retromandibular transparotid approach to displaced extracapsular subcondylar mandibular fractures. PATIENTS AND METHODS: A prospective cohort study was conducted over a period of 5 years on patients surgically treated for displaced extracapsular subcondylar mandibular fractures by the retromandibular transparotid approach. Variables including the type of fracture, degree of mouth opening, fracture displacement, deviation, excursive movements of the mandible, and facial nerve function were monitored before and after treatment. Appropriate statistics were computed. RESULTS: Thirty-nine patients with 47 fractures were evaluated. There were 34 subcondylar fractures (located below the sigmoid notch) (87%), and 5 fractures were located in the head region in bilateral cases. Of the fractures, 31 (79%) were unilateral and 8 (21%) were bilateral. In a multivariate study, condylar coronal displacement, coronal sagittal displacement, difference in the ramal height, maximal interincisal distance, protrusive movements, and deviation of the mandible on opening showed statistically significant differences in pretreatment and post-treatment patients (P = .001). The interincisal distance was 46.8 mm (SD, 5.2 mm) postoperatively versus 24.1 mm (SD, 6.7 mm) before treatment. The average range of protrusion was significantly lower (P = .001) in patients before treatment, at 1.9 mm (SD, 1.2 mm), when compared with 6.1 mm (SD, 2.0 mm) postoperatively. During mouth opening, deviation of the mandible is often a sign of compensatory movement of the contralateral joint due to shortening of the ascending ramal height on the affected joint. The mean deviation of the mandible from the midline was 4.2 mm (SD, 1.0 mm) in patients before treatment, with a significant difference (P = .001) in patients after treatment, with a mean of 1.9 mm (SD, 0.995 mm). Temporary injuries to the facial nerve branches were observed in 3 cases (8%) 1 week after treatment, which later resolved within 3 weeks to 3 months. CONCLUSIONS: The retromandibular transparotid approach provides good exposure and facilitates accurate reduction and fixation of the subcondylar fragment with positive outcomes, good cosmetic results, and rare major complications. Most facial nerve injuries are transient in nature after this approach. A Synthes 2-mm titanium single mini-plate (West Chester, PA) provides stable results after fixation.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas Mandibulares/cirurgia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
12.
Biochim Biophys Acta ; 1844(10): 1827-34, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25110178

RESUMO

Intrinsically disordered proteins (IDPs)/protein regions (IDPRs) lack unique three-dimensional structure at the level of secondary and/or tertiary structure and are represented as an ensemble of interchanging conformations. To investigate the role of presence/absence of secondary structures in promoting intrinsic disorder in proteins, a comparative sequence analysis of IDPs, IDPRs and proteins with minimal secondary structures (less than 5%) is required. A sequence analysis reveals proteins with minimal secondary structure content have high mean net positive charge, low mean net hydrophobicity and low sequence complexity. Interestingly, analysis of the relative local electrostatic interactions reveal that an increase in the relative repulsive interactions between amino acids separated by three or four residues lead to either loss of secondary structure or intrinsic disorder. IDPRs show increase in both local negative-negative and positive-positive repulsive interactions. While IDPs show a marked increase in the local negative-negative interactions, proteins with minimal secondary structure depict an increase in the local positive-positive interactions. IDPs and IDPRs are enriched in D, E and Q residues, while proteins with minimal secondary structure are depleted of these residues. Proteins with minimal secondary structures have higher content of G and C, while IDPs and IDPRs are depleted of these residues. These results confirm that proteins with minimal secondary structure have a distinctly different propensity for charge, hydrophobicity, specific amino acids and local electrostatic interactions as compared to IDPs/IDPRs. Thus we conclude that lack of secondary structure may be a necessary but not a sufficient condition for intrinsic disorder in proteins.

13.
Int J Syst Evol Microbiol ; 65(10): 3720-3726, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26219279

RESUMO

A Gram-negative-staining, aerobic, non-motile, non-spore-forming, rod-shaped and yellow-pigmented bacterium, designated R11HT, was isolated from a soil sample collected from a hexachlorocyclohexane dumpsite located at Ummari village, Lucknow, Uttar Pradesh, India. The 16S rRNA gene sequence similarity between strain R11HT and the type strains of species of genus Sphingopyxis with validly published names ranged from 93.75 to 97.85 %. Strain R11HT showed the highest 16S rRNA gene sequence similarity to Sphingopyxis indica DS15T (97.85 %), followed by Sphingopyxis soli JCM15910T (97.79 %), Sphingopyxis ginsengisoli KCTC 12582T (97.77 %) and Sphingopyxis panaciterrulae KCTC 22112T (97.34 %). The DNA G+C content of strain R11HT was 63.5 mol%. DNA-DNA relatedness between strain R11HT and its closest phylogenetic neighbours was well below the threshold value of 70 %, which suggested that strain R11HT represents a novel species of the genus Sphingopyxis. The major polar lipids of strain R11HT were sphingoglycolipid and other lipids commonly reported in this genus, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylmonomethylethanolamine. Spermidine was detected as the major polyamine. The chemotaxonomic markers in strain R11HT confirmed its classification in the genus Sphingopyxis, i.e. Q-10 as the major ubiquinone and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C14 : 0 2-OH as the predominant fatty acids. Results obtained from DNA-DNA hybridization and chemotaxonomic and phenotypic analyses clearly distinguished strain R11HT from its closest phylogenetic neighbours. Thus, strain R11HT represents a novel species of the genus Sphingopyxis, for which the name Sphingopyxis flava sp. nov. is proposed. The type strain is R11HT ( = DSM 28472T = MCC 2778T).


Assuntos
Hexaclorocicloexano/análise , Filogenia , Microbiologia do Solo , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes do Solo/análise , Espermidina/química , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Ubiquinona/análogos & derivados , Ubiquinona/química
14.
Int J Syst Evol Microbiol ; 65(Pt 1): 129-134, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25298380

RESUMO

Strain RK1(T), a Gram-stain-negative, non-spore-forming, rod-shaped, non-motile bacterium was isolated from a hexachlorocyclohexane (HCH) dumpsite, Lucknow, India. 16S rRNA gene sequence analysis revealed that strain RK1(T) belongs to the family Sphingobacteriaceae and showed highest sequence similarity to Parapedobacter koreensis Jip14(T) (95.63%). The major cellular fatty acids of strain RK1(T) were iso-C15:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c), iso-C17:0 3-OH, summed feature 9 (10-methyl C16:0 and/or iso-C17:1ω9c), iso-C15:0 3-OH and C16 : 0. The major respiratory pigment and polyamine of RK1(T) were menaquinone (MK-7) and homospermidine, respectively. The main polar lipids were phosphatidylethanolamine and sphingolipid. The G+C content of the DNA was 44.5 mol%. The results of physiological and biochemical tests and 16S rRNA sequence analysis clearly demonstrated that strain RK1(T) represents a novel species of the genus Parapedobacter, for which the name Parapedobacter indicus sp. nov. is proposed. The type strain is RK1(T) ( = DSM 28470(T) =MCC 2546(T)).


Assuntos
Bacteroidetes/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hexaclorocicloexano/análise , Índia , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes do Solo/análise , Espermidina/química , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
ScientificWorldJournal ; 2014: 847482, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24523650

RESUMO

Ocimum tenuiflorum L., holy basil "Tulsi", is an important medicinal plant that is being grown and traditionally revered throughout Indian Subcontinent for thousands of years; however, DNA sequence-based genetic diversity of this aromatic herb is not yet known. In this report, we present our studies on the phylogeography of this species using trnL-trnF intergenic spacer of plastid genome as the DNA barcode for isolates from Indian subcontinent. Our pairwise distance analyses indicated that genetic heterogeneity of isolates remained quite low, with overall mean nucleotide p-distance of 5 × 10(-4). However, our sensitive phylogenetic analysis using maximum likelihood framework was able to reveal subtle intraspecific molecular evolution of this species within the subcontinent. All isolates except that from North-Central India formed a distinct phylogenetic clade, notwithstanding low bootstrap support and collapse of the clade in Bayesian Inference. North-Central isolates occupied more basal position compared to other isolates, which is suggestive of its evolutionarily primitive status. Indian isolates formed a monophyletic and well-supported clade within O. tenuiflorum clade, which indicates a distinct haplotype. Given the vast geographical area of more than 3 million km(2) encompassing many exclusive biogeographical and ecological zones, relatively low rate of evolution of this herb at this locus in India is particularly interesting.


Assuntos
DNA de Cloroplastos , Ocimum basilicum/classificação , Ocimum basilicum/genética , Filogenia , Filogeografia , Índia
16.
Int J Biol Macromol ; 262(Pt 2): 130221, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38365159

RESUMO

The present study involves the isolation of cellulose nanofibers from pineapple crown waste by a combined alkali-acid treatment method. The extracted pineapple nanofibers were characterized by Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, nuclear magnetic resonance, high-resolution transmission electron microscopy, and dynamic light scattering. The extracted pineapple nanofibers were then incorporated in Carbopol 934P containing ketoconazole to prepare a ketoconazole-loaded pineapple nanofibrous gel. The prepared gel formulation was evaluated for viscosity, spreadability, extrudibility, pH, drug content, and texture profile analysis. The anticipated gel formulation was further evaluated by in vitro drug release (98.57 ± 0.58 %), ex vivo drug permeation, cytotoxicity, and histopathological studies. The permeation of the drug through skin determined by the ex-vivo diffusion study was found to be 38.27 % with a flux rate of 4.06 ± 0.26 µg/cm2/h. Further, the cytotoxicity study of pineapple nanofiber and ketoconazole-loaded nanofiber gel displayed no cytotoxic on healthy vero cells in the concentration range from 10 to 80 µg/ml. The histopathological analysis exhibited no signs of distress and inflammation. In conclusion, ketoconazole-loaded pineapple nanofiber gel could be considered as a promising delivery system for topical applications.


Assuntos
Ananas , Nanofibras , Animais , Chlorocebus aethiops , Cetoconazol/farmacologia , Nanofibras/química , Células Vero , Celulose
17.
Foods ; 13(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38890965

RESUMO

This study aims to focus on developing a food supplement for the geriatric population using disposal mushrooms, oats, and lactose-free milk powder. Lactose intolerance is most common in older adults, raising the demand for lactose-free foods. One of the major global challenges currently faced by humankind is food waste (FW). Most of the food that is produced for human consumption has not been utilized completely (1/3rd-1/2 unutilized), resulting in agricultural food waste. Mushrooms are highly valuable in terms of their nutritional value and medicinal properties; however, a significant percentage of mushroom leftovers are produced during mushroom production that do not meet retailers' standards (deformation of caps/stalks) and are left unattended. Oats are rich in dietary fibre beta-glucan (55% water soluble; 45% water insoluble). Lactose-free milk powder, oats, and dried mushroom leftover powder were blended in different ratios. It was observed that increasing the amount of mushroom leftover powder increases the protein content while diluting calories. The product with 15% mushroom powder and 30% oat powder showed the highest sensory scores and the lowest microbial count. The GCMS and FTIR analyses confirmed the presence of ergosterol and other functional groups. The results of the XRD analysis showed that the product with 15% mushroom powder and 30% oat powder had a less crystalline structure than the product with 5% mushroom powder and 40% oat powder and the product with 10% mushroom powder and 35% oat powder, resulting in more solubility. The ICP-OES analysis showed significant concentrations of calcium, potassium, magnesium, sodium, and zinc. The coliform count was nil for the products, and the bacterial count was below the limited range (3 × 102 cfu/g). The product with 15% mushroom powder and 30% oat powder showed the best results, so this developed product is recommended for older adults.

18.
ACS Appl Mater Interfaces ; 16(15): 18327-18343, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38588343

RESUMO

58S bioactive glass (BG) has effective biocompatibility and bioresorbable properties for bone tissue engineering; however, it has limitations regarding antibacterial, antioxidant, and mechanical properties. Therefore, we have developed BGAC biocomposites by reinforcing 58S BG with silver and ceria nanoparticles, which showed effective bactericidal properties by forming inhibited zones of 2.13 mm (against Escherichia coli) and 1.96 mm (against Staphylococcus aureus; evidenced by disc diffusion assay) and an increment in the antioxidant properties by 39.9%. Moreover, the elastic modulus, hardness, and fracture toughness were observed to be increased by ∼84.7% (∼51.9 GPa), ∼54.5% (∼3.4 GPa), and ∼160% (∼1.3 MPam1/2), whereas the specific wear rate was decreased by ∼55.2% (∼1.9 × 10-11 m3/Nm). X-ray diffraction, high-resolution transmission electron microscopy, and field emission scanning electron microscopy confirmed the fabrication of biocomposites and the uniform distribution of the nanomaterials in the BG matrix. The addition of silver nanoparticles in the 58S BG matrix (in BGA) increased mechanical properties by composite strengthening and bactericidal properties by damaging the cytoplasmic membrane of bacterial cells. The addition of nanoceria in 58S BG (BGC) increased the antioxidant properties by 44.5% (as evidenced by the 2,2-diphenyl-1-picrylhydrazyl assay). The resazurin reduction assay and MTT assay confirmed the effective cytocompatibility for BGAC biocomposites against mouse embryonic fibroblast cells (NIH3T3) and mouse bone marrow stromal cells. Overall, BGAC resulted in mechanical properties comparable to those of cancellous bone, and its effective antibacterial and cytocompatibility properties make it a good candidate for bone healing.


Assuntos
Cério , Nanopartículas Metálicas , Prata , Animais , Camundongos , Antioxidantes , Células NIH 3T3 , Fibroblastos , Antibacterianos/farmacologia , Vidro
19.
Assay Drug Dev Technol ; 22(2): 86-96, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38150558

RESUMO

A reverse-phase high-performance liquid chromatographic (RP-HPLC) method was developed to analyze the simultaneous estimation of doxorubicin and clotrimazole. The method was achieved by Nucleodur C18 column with dimension 250 × 4.6 mm (5 µm) using gradient elution. The mobile phase contained 0.2% formic acid (pH 3.2) and acetonitrile. The flow rate was kept at 1.0 mL/min and detection and quantitation of both drugs (doxorubicin and clotrimazole) were achieved using a photodiode array detector at 276 nm, which was the isosbestic point for both drugs. The proposed method was validated according to the current International Council for Harmonization of Technical Requirements of Pharmaceuticals for Human Use guidelines for specificity, linearity, accuracy, precision, and robustness. The developed method showed a linear response (R2 > 0.999), and was accurate (recoveries 97%-103%), precise (resolution ≤1.0%), sensitive, and specific. Thus, the developed RP-HPLC method for the simultaneous estimation of both drugs was successfully validated and can be utilized for the estimation of these drugs in the formulations being developed.


Assuntos
Cromatografia de Fase Reversa , Clotrimazol , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Doxorrubicina
20.
J Chem Phys ; 138(9): 095101, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23485328

RESUMO

The recently developed methods of constant pH molecular dynamics directly captures the correlation between protonation and conformation to probe protein structure, function, and dynamics. In this work, we investigate the effect of pH on the conformational properties of the protein human α-lactalbumin. Constant pH simulations at both acidic and alkaline medium indicate the formation of the molten globule state, which is in accordance with the previous experimental observations (especially, in acidic medium). The size of the protein measured by its radius of gyration (RG) exhibits a marked increase in both acidic and alkaline medium, which matches with the corresponding experimentally observed value of RG found in the molten globule. The probability of native contacts is also considerably reduced at acidic and basic pH as compared to that of native structure crystallized at neutral pH. The mean fractal dimension D2 of the protein records a sharp increase in basic medium as compared to those in neutral and acidic solutions implying a significant pH induced conformational change. The mean square fluctuations of all residues of the entire protein are found to increase by several folds in both acidic and basic medium, which may be correlated with the normalized solvent accessibility of the residues indicating role of solvent accessible surface area on protein internal dynamics. The helices comprising the α-domain of the protein are moderately preserved in the acidic and alkaline pH. However, the ß-sheet structures present in the ß-domain are completely disrupted in both acidic as well as basic pH.


Assuntos
Lactalbumina/química , Simulação de Dinâmica Molecular , Humanos , Concentração de Íons de Hidrogênio , Estrutura Secundária de Proteína
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