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1.
J Community Psychol ; 50(2): 742-759, 2022 03.
Article in English | MEDLINE | ID: mdl-34291825

ABSTRACT

PURPOSE: This explanatory research aims to describe the factors that impact YouTube ad intrusiveness, value, and avoidance in light of psychological reactance theory. RESEARCH DESIGN: The research has a causal-predictive design. It describes the relationship between the construct with an underpinning theory. Data from a sample of 294 respondents were analyzed using partial least square structural equation modeling to test within sample explanatory power and out-of-sample prediction power. FINDINGS: The results show that informativeness does not significantly impact intrusiveness and ad avoidance. Entertainment has a negative direct and mediated impact on ad avoidance. Moreover, irritation was found to moderate the impact of informativeness on intrusiveness negatively. Importance-Performance Map Analysis revealed that entertainment lacks in performance despite being an essential factor. Besides explanatory power, the model has a moderate out-of-sample predictive relevance power. PRACTICAL IMPLICATIONS: The relative importance of the entertainment and interactive impact of irritation with informativeness is established for the first time in this study. The new finding is a significant contribution to theory while leading to practical implications for the industry.

2.
Chemistry ; 26(49): 11209-11219, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32227539

ABSTRACT

The use of water splitting modules is highly desired for the sustainable production of H2 as a future energy carrier. However, the sluggish kinetics and demand of high anodic potential are the bottlenecks for half-the cell oxygen evolution reaction (OER), which severely hamper the overall conversion efficiency. Although transition metal oxides based electrocatalysts have been envisioned as cost-effective and potential contenders for this quest, nevertheless, their low conductivity, instability, and limited number of active sites are among the common impediments that need to be addressed to eventually enhance their inherent catalytic potential for enhanced OER activity. Herein, the controlled assembly of transition metal oxides, that is, Cu@CuOx nanoclusters (NCs, ≈2 nm) and Co@CoOx beaded nanoclusters (BNCs, ≈2 nm), on thiol-functionalized graphene oxide (G-SH) nanosheets is reported to form novel and highly efficient electrocatalysts for OER. The thiol (-SH) functionality was incorporated by selective epoxidation on the surface of graphene oxide (GO) to achieve chemically exfoliated nanosheets to enhance its conductivity and trapping ability for metal oxides in nanoscale dimensions (≈2 nm). During the electrocatalytic reaction, overpotentials of 290 mV and 310 mV are required to achieve a current density of 10 mA cm-2 for BNCs and NCs, respectively, and the catalysts exhibit tremendous long-term stability (≈50 h) in purified alkaline medium (1 m KOH) with no dissolution in the electrolyte. Moreover, the smaller Tafel slopes (54 mV/dec for BNCs and 66 mV/dec for NCs), and a Faradic efficiency of approximately 96 % indicate not only the selectivity but also the tailored heterogeneous electrons transfer (HET) rate, which is required for fast electrode kinetics. It is anticipated that such ultrasmall metal oxide nanoclusters and their controlled assembly on a conducting surface (G-SH) may offer high electrochemical accessibility and a plethora of active sites owing to the drastic decrease in dimensions and thus can synergistically ameliorate the challenging OER process.

3.
J Pak Med Assoc ; 69(8): 1216-1218, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31431784

ABSTRACT

Peripartum cardiomyopathy (PPCM) is a condition of unknown etiology that presents as heart failure due to left ventricular systolic dysfunction in the last of month of pregnancy and up to six months after giving birth. PPCM predisposes towards thrombo-embolism and an acute limb ischaemia can be a manifestation of this disease. We present a case of a 23-year-old lady presenting an acute lower limb ischaemia four months post-partum. Doppler ultrasound showed bilateral femoral emboli and cardiac ECHO showed a 24% ejection fraction. Amputation was performed on both limbs, below her right knee and above her left knee. The patient was started on heart failure medication and her symptoms improved with diuretic therapy, confirming the diagnoses of PPCM. It is important to recognise acute limb ischaemia as a rare manifestation of PPCM, as a timely diagnosis and effective treatment of the disease can improve the prognosis. We believe this is the first case to be reported in medical literature from Pakistan of a patient presenting PPCM with bilateral acute limb ischaemia and gangrene.


Subject(s)
Cardiomyopathies/complications , Embolism/etiology , Femoral Artery/diagnostic imaging , Gangrene/etiology , Ischemia/etiology , Puerperal Disorders/diagnostic imaging , Amputation, Surgical , Cardiomyopathies/diagnostic imaging , Echocardiography , Embolectomy , Embolism/diagnostic imaging , Embolism/surgery , Female , Gangrene/surgery , Humans , Ischemia/diagnostic imaging , Lower Extremity , Stroke Volume , Treatment Failure , Ultrasonography, Doppler , Young Adult
4.
J Pak Med Assoc ; 69(9): 1390-1393, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31511733

ABSTRACT

Chromoblastomycosis is a chronic fungal infection of the subcutaneous tissue. The infection usually results from a traumatic injury and inoculation of the microorganism by a specific group of dematiaceous fungi, resulting in the formation of verrucous plaques. The fungi produce sclerotic or medlar bodies (also called muriform bodies or sclerotic cells) seen on direct microscopic examination of skin smears. The disease is often found in adults due to trauma. We report a case of chromoblastomycosis in a 12-year-old child in whom the infection started when he was only 4 years old with secondary involvement of bones, cartilage, tongue and palatine tonsils. The child was not immunosuppressed.


Subject(s)
Bone Diseases, Infectious/diagnostic imaging , Chromoblastomycosis/diagnosis , Invasive Fungal Infections/diagnosis , Staphylococcal Infections/diagnosis , Anti-Bacterial Agents/therapeutic use , Bone Diseases, Infectious/drug therapy , Carbaryl/therapeutic use , Child , Chromoblastomycosis/diagnostic imaging , Chromoblastomycosis/drug therapy , Finger Joint/diagnostic imaging , Humans , Invasive Fungal Infections/diagnostic imaging , Invasive Fungal Infections/drug therapy , Lymphadenopathy/diagnosis , Male , Metatarsophalangeal Joint/diagnostic imaging , Methicillin-Resistant Staphylococcus aureus , Palatine Tonsil , Pharyngeal Diseases/diagnosis , Pharyngeal Diseases/drug therapy , Staphylococcal Infections/drug therapy
5.
J Sep Sci ; 39(4): 793-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26632078

ABSTRACT

In the present work, novel molecularly imprinted polymer porous beads for the selective separation of copper ions have been synthesized by combining two material-structuring techniques, namely, molecular imprinting and oil-in-water-in-oil emulsion polymerization. This method produces monodisperse spherical beads with an average diameter of ∼2-3 mm, in contrast to adsorbents produced in the traditional way of grinding and sieving. Field-emission scanning electron microscopy indicates that the beads are porous in nature with interconnected pores of about 25-50 µm. Brunner-Emmett-Teller analysis shows that the ion-imprinted beads possess a high surface area (8.05 m(2) /g), and the total pore volume is determined to be 0.00823 cm(3) /g. As a result of the highly porous nature and ion-imprinting, the beads exhibit a superior adsorption capacity (84 mg/g) towards copper than the non-imprinted material (22 mg/g). Furthermore, selectivity studies indicate that imprinted beads show splendid recognizing ability, that is, nearly fourfold greater selective binding for Cu(2+) in comparison to the other bivalent ions such as Mn(2+) , Ni(2+) , Co(2+) , and Ca(2+) . The imprinted composite beads prepared in this study possess uniform porous morphology and may open up new possibilities for the selective removal of copper ions from waste water/contaminated matrices.

6.
Analyst ; 140(21): 7366-72, 2015 Nov 07.
Article in English | MEDLINE | ID: mdl-26381602

ABSTRACT

Salmonella enterica serotype Typhi (S. Typhi) is the causative agent of typhoid fever and remains a major health threat in most of the developing countries. The prompt diagnosis of typhoid directly from the patient's blood requires high level of sensitivity and specificity. Some of us were the first to report PCR based diagnosis of typhoid. This approach has since then been reported by many scientists using different genomic targets. Since the number of bacteria circulating in the blood of a patient can be as low as 0.3 cfu ml(-1), there is always a room for improvement in diagnostic PCR. In the present study, the role of different types of nanoparticles was investigated to improve the existing PCR based methods for diagnosis and strain typing of S. Typhi (targeting Variable Number of Tandem Repeats [VNTR]) by using optimized PCR systems. Three different types of nanoparticles were used i.e., citrate stabilized gold nanoparticles, rhamnolipid stabilized gold and silver nanoparticles, and magnetic iron oxide nanoparticles. The non-specific amplification was significantly reduced in VNTR typing when gold and silver nanoparticles were used in an appropriate concentration. More importantly, the addition of nanoparticles decreased the non-specificity to a significant level in the case of multiplex PCR thus further validating the reliability of PCR for the diagnosis of typhoid.


Subject(s)
Bacterial Typing Techniques , Metal Nanoparticles/chemistry , Polymerase Chain Reaction/methods , Salmonella typhi/classification , Typhoid Fever/diagnosis , Typhoid Fever/microbiology , Bacterial Proteins/chemistry , DNA Primers/chemistry , Escherichia coli Proteins/genetics , Ferric Compounds/chemistry , Flagellin , Gold/chemistry , Magnetics , Minisatellite Repeats , Nanotechnology/methods , Reproducibility of Results , Sensitivity and Specificity , Silver/chemistry , Temperature
7.
J Microencapsul ; 31(5): 461-8, 2014.
Article in English | MEDLINE | ID: mdl-24495195

ABSTRACT

The present study dealt with emulsive fabrication of chitosan microcapsules encapsulating essential oils in the present of bio/surfactant. The size distribution, morphology and stability of microcapsules were examined by using advanced surface characterisation techniques. At cetyl trimethyl ammonium bromide (CTAB) concentration of 330 mg/L, the smallest average size of microcapsules was observed as12.8 µm; whereas with biosurfactant at 50 mg/L, the microcapsules of smallest average size of 7.5 µm were observed. The fabricated microcapsules were applied on a desized, bleached and mercerised cotton fabric by using pad-dry-cure method by using a modified dihydroxy ethylene urea as a cross-linking agent. The cross-linking was confirmed by using scanning electron microscopy and Fourier transform infrared spectroscopy techniques. The antibacterial activity of finished fabric was evaluated using the turbidity estimation method. The stiffness and wrinkle recovery properties of the treated fabric were also investigated by using the standard methods. In general, antibacterial activity of treated fabric increased with the increase in chitosan and essential oil concentrations, whereas stiffness increased with increase in concentration of chitosan but decreased with increase in essential oil concentration.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Chitosan/chemistry , Cotton Fiber , Oils, Volatile/administration & dosage , Anti-Bacterial Agents/pharmacology , Cetrimonium , Cetrimonium Compounds/chemistry , Drug Compounding , Escherichia coli/drug effects , Escherichia coli Infections/prevention & control , Humans , Oils, Volatile/chemistry , Spectroscopy, Fourier Transform Infrared , Staphylococcal Infections/prevention & control , Staphylococcus aureus/drug effects
8.
J Med Chem ; 67(12): 10005-10011, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38511243

ABSTRACT

There is an urgent requirement to acquire a comprehensive comprehension of novel therapeutic targets for prostate cancer to facilitate the development of medications with innovative mechanisms. In this study, we identified gambogic acid (GBA) as a specific pyroptosis inducer in prostatic cancer cells. By using a thermal proteome profiling (TPP) strategy, we revealed that GBA induces pyroptosis by directly targeting the canopy FGF signaling regulator (CNPY3), which was previously considered "undruggable". Moreover, through the utilization of the APEX2-based proximity labeling method, we found that GBA recruited delactatease SIRT1, resulting in the elimination of lysine lactylation (Kla) on CNPY3. Of note, SIRT1-mediated delactylation influenced the cellular localization of CNPY3 to promote lysosome rupture for triggering pyroptosis. Taken together, our study identified CNPY3 as a distinctive cellular target for pyroptosis induction and its potential application in prostate cancer therapy.


Subject(s)
Prostatic Neoplasms , Proteome , Pyroptosis , Xanthones , Male , Humans , Xanthones/pharmacology , Xanthones/chemistry , Prostatic Neoplasms/pathology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/drug therapy , Pyroptosis/drug effects , Proteome/metabolism , Proteome/drug effects , Cell Line, Tumor , Sirtuin 1/metabolism
9.
AMB Express ; 13(1): 115, 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37848594

ABSTRACT

Antibiotic-resistant bacterial strains and the consequent surge in infections caused by them have become major public health concerns. Silver nanoparticles (AgNPs) exhibit antibacterial properties and have wide applications in biomedical sciences. In this study, AgNPs were synthesized in the presence of antibiotics: Ceftazidime (Cft), Cefotaxime (Cef), Ceftriaxone (Cfx), and Cefepime (Cpm), along with the extract of Mentha longifolia. Mentha longifolia-based AgNPs were kept as the control for all experiments. The associated metabolites, structural properties, surface charges, and antibacterial activity of the AgNPs were also evaluated. Overall, a blue-shift of SPR peaks was observed for control AgNPs (λmax = 421 nm, 422 nm, 426 nm, and 406 nm for Cft-AgNPs, Cef-AgNPs, Cfx-AgNPs, and Cpm-AgNPs, respectively), compared to the control (λmax = 438 nm). Fourier-transform infrared spectroscopy showed that antibiotic-based AgNPs had distinct peaks that corresponded to the respective antibiotics, which were not observed in the control. XRD analysis showed that there were observed changes in crystallinity in antibiotic-based AgNPs compared to the control. TEM images revealed that all samples had spherical nanoparticles with different sizes and distributions compared to the control. The Zeta potential for extract-based AgNPs was - 33.6 mV, compared to -19.6 mV for Cft-AgNPs, -2 mV for Cef-AgNPs, -21.1 mV for Cfx-AgNPs, and - 24.2 mV for Cpm-AgNPs. The increase in the PDI value for antibiotic-based AgNPs also showed a highly polydisperse distribution. However, the antibiotic-AgNPs conjugates showed significantly higher activity against pathogenic bacteria. The addition of antibiotics to AgNPs brought significant changes in structural properties and antibacterial activities.

10.
ACS Appl Mater Interfaces ; 15(37): 43321-43331, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37668507

ABSTRACT

The emergence of antimicrobial resistance is an alarming global health concern and has stimulated the development of novel functional nanomaterials to combat multi-drug-resistant (MDR) bacteria. In this work, we demonstrate for the first time the synthesis and application of surfactin-coated silver nanoparticles as an efficient antibacterial and antibiofilm agent against the drug-resistant bacteria Pseudomonas aeruginosa for safe dermal applications. Our in vivo studies showed no significant superficial dermal irritation, edema, and erythema, while microscopic analysis revealed that surfactin-coated silver nanoparticles caused no pathological alterations at the applied concentrations. These results support the potential use of surfactin-coated silver nanoparticles against drug-resistant bacterial biofilm infections and in skin wound dressing applications.


Subject(s)
Metal Nanoparticles , Pseudomonas aeruginosa , Silver/pharmacology , Anti-Bacterial Agents/pharmacology , Biofilms
11.
Nat Commun ; 14(1): 1130, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36854666

ABSTRACT

SARS-CoV-2 variants have emerged with elevated transmission and a higher risk of infection for vaccinated individuals. We demonstrate that a recombinant prefusion-stabilized spike (rS) protein vaccine based on Beta/B.1.351 (rS-Beta) produces a robust anamnestic response in baboons against SARS-CoV-2 variants when given as a booster one year after immunization with NVX-CoV2373. Additionally, rS-Beta is highly immunogenic in mice and produces neutralizing antibodies against WA1/2020, Beta/B.1.351, and Omicron/BA.1. Mice vaccinated with two doses of Novavax prototype NVX-CoV2373 (rS-WU1) or rS-Beta alone, in combination, or heterologous prime-boost, are protected from challenge. Virus titer is undetectable in lungs in all vaccinated mice, and Th1-skewed cellular responses are observed. We tested sera from a panel of variant spike protein vaccines and find broad neutralization and inhibition of spike:ACE2 binding from the rS-Beta and rS-Delta vaccines against a variety of variants including Omicron. This study demonstrates that rS-Beta vaccine alone or in combination with rS-WU1 induces antibody-and cell-mediated responses that are protective against challenge with SARS-CoV-2 variants and offers broader neutralizing capacity than a rS-WU1 prime/boost regimen alone. Together, these nonhuman primate and murine data suggest a Beta variant booster dose could elicit a broad immune response to fight new and future SARS-CoV-2 variants.


Subject(s)
COVID-19 Vaccines , COVID-19 , Nanoparticles , Animals , Humans , Mice , Antibodies, Neutralizing , COVID-19/prevention & control , Papio , SARS-CoV-2/genetics , Vaccines/chemistry , Vaccines/immunology , COVID-19 Vaccines/chemistry , COVID-19 Vaccines/immunology
12.
Health Care Women Int ; 33(12): 1114-34, 2012.
Article in English | MEDLINE | ID: mdl-23153347

ABSTRACT

In Qatar, cardiovascular diseases are the leading causes of morbidity and mortality. Cardiovascular diseases can be prevented and controlled by modifying lifestyle risk behaviors. In this qualitative study, we investigate ways to increase participation in physical activity, and to promote a healthy diet, and nonsmoking behavior in Qatari women. Individual in-depth interviews were conducted with 50 Arabic women. Participation in physical activity, observing a healthy diet, and abstinence from smoking are desirable lifestyle practices among Qatari women. Social support networks, cultural values, religion, changing sociodemographic and economic conditions, heart disease, and a harsh climate affect the ability of these women to pursue a healthy lifestyle.


Subject(s)
Cardiovascular Diseases/psychology , Exercise/psychology , Health Behavior , Health Knowledge, Attitudes, Practice , Health Promotion/methods , Adult , Aged , Arabs/psychology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/therapy , Cultural Characteristics , Female , Humans , Interviews as Topic , Life Style , Middle Aged , Motivation , Qatar/epidemiology , Qualitative Research , Risk Factors , Risk-Taking , Social Support , Socioeconomic Factors
13.
Curr Top Med Chem ; 22(13): 1046-1067, 2022.
Article in English | MEDLINE | ID: mdl-34961445

ABSTRACT

The rapid emergence of multidrug-resistant bacterial strains highlights the need for the development of new antimicrobial compounds/materials to address associated healthcare challenges. Meanwhile, the adverse side effects of conventional antibiotics on human health urge the development of new natural product-based antimicrobials to minimize the side effects. In this respect, we concisely review the recent scientific contributions to develop natural product-based nano-antibiotics. The focus of the review is on the use of flavonoids, peptides, and cationic biopolymer functionalized metal/metal oxide nanoparticles as efficient tools to hit the MDR bacterial strains. It summarizes the most recent aspects of the functionalized nanoparticles against various pathogenic bacterial strains for their minimal inhibitory concentrations and mechanism of action at the cellular and molecular levels. In the end, the future perspectives to materialize the in vivo applications of nano-antimicrobials are suggested based on the available research.


Subject(s)
Anti-Infective Agents , Biological Products , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/pharmacology , Bacteria , Drug Resistance, Multiple, Bacterial , Humans , Microbial Sensitivity Tests
14.
3 Biotech ; 12(10): 273, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36101547

ABSTRACT

The COVID-19 outbreak has brought the world, at least, to one consensus that cleanliness is unavoidable under all circumstances. Hands are the main body part to interact with the environment and thus are prone to receive, initiate and propagate the chain of infection. Hand hygiene has, therefore, been most emphasized by experts to interrupt the spread of infection. Various harsh chemicals like synthetic surfactants and alcoholic preparations have been in practice to eradicate and disinfect the germs. This choice may be unsafe and cause a subsequent chain of adversities. Thereby, biosurfactants have been proposed as sustainable, non-toxic and safe surface cleaners cum disinfectants under a wide range of physiological and environmental conditions. The amphiphilic micellar behavior of biosurfactants makes them promising candidates as hygienic surface cleaners and therapeutic carriers. We overview the possibilities of using biosurfactants in different ways against microbial pathogens, in general, and the SARS COV-2, in specific.

15.
Virus Res ; 296: 198343, 2021 04 15.
Article in English | MEDLINE | ID: mdl-33607183

ABSTRACT

Flaviviruses are the fastest spreading arthropod-borne viruses that cause severe symptoms such as hepatitis, hemorrhagic fever, encephalitis, and congenital deformities. Nearly 40 % of the entire human population is at risk of flavivirus epidemics. Yet, effective vaccination is restricted only to a few flaviviruses such as yellow fever and Japanese encephalitis viruses, and most recently for select cases of dengue virus infections. Despite the global spread of dengue virus, and emergence of new threats such as Zika virus and a new genotype of Japanese encephalitis virus, insights into flavivirus targets for potentially broad-spectrum vaccination are limited. In this review article, we highlight biochemical and structural differences in flavivirus proteins critical for virus assembly and host interactions. A comparative sequence analysis of pH-responsive properties of viral structural proteins identifies trends in conservation of complementary acidic-basic character between interacting viral structural proteins. This is highly relevant to the understanding of pH-sensitive differences in virus assembly in organelles such as neutral ER and acidic Golgi. Surface residues in viral interfaces identified by structural approaches are shown to demonstrate partial conservation, further reinforcing virus-specificity in assembly and interactions with host proteins. A comparative analysis of epitope conservation in emerging flaviviruses identifies therapeutic antibody candidates that have potential as broad spectrum anti-virals, thus providing a path towards development of vaccines.


Subject(s)
Flavivirus Infections , Flavivirus , Yellow Fever , Zika Virus Infection , Zika Virus , Flavivirus/genetics , Humans , Viral Structural Proteins , Yellow Fever/prevention & control , Zika Virus/genetics
16.
Photodiagnosis Photodyn Ther ; 33: 102152, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33348077

ABSTRACT

BACKGROUND: Raman spectroscopy is a promising technique to analyze the body fluids for the purpose of non-invasive disease diagnosis. OBJECTIVES: To develop a surface-enhanced Raman spectroscopy (SERS) based method for qualitative and quantitative analysis of HCV from blood samples. METHODS: SERS was employed to characterize the Hepatitis C viral RNA extracted from different blood samples of hepatitis C virus (HCV) infected patients with predetermined viral loads in comparison with total RNA of healthy individuals. The SERS measurements were performed on 27 extracted RNA samples including low viral loads, medium viral loads, high viral loads and healthy/negative viral load samples. For this purpose, silver nanoparticles (Ag NPs) were used as SERS substrates. Furthermore, multivariate data analysis technique, Principal Component Analysis (PCA) and Partial Least Square Regression (PLSR) were also performed on SERS spectral data. RESULTS: The SERS spectral features due to biochemical changes in the extracted RNA samples associated with the increasing viral loads were established which could be employed for HCV diagnostic purpose. PCA was found helpful for the differentiation between Raman spectral data of RNA extracted from hepatitis infected and healthy blood samples. PLSR model is established for the determination of viral loads in HCV positive RNA samples with 99 % accuracy. CONCLUSION: SERS can be employed for qualitative and quantitative analysis of HCV from blood samples.


Subject(s)
Hepatitis C , Metal Nanoparticles , Photochemotherapy , Hepacivirus/genetics , Hepatitis C/diagnosis , Humans , Photochemotherapy/methods , Photosensitizing Agents , RNA , Silver , Spectrum Analysis, Raman , Viral Load
17.
J Bone Miner Res ; 36(3): 531-545, 2021 03.
Article in English | MEDLINE | ID: mdl-33125761

ABSTRACT

ClC-7 is a chloride-proton antiporter of the CLC protein family. In complex with its accessory protein Ostm-1, ClC-7 localizes to lysosomes and to the osteoclasts' ruffled border, where it plays a critical role in acidifying the resorption lacuna during bone resorption. Gene inactivation in mice causes severe osteopetrosis, neurodegeneration, and lysosomal storage disease. Mutations in the human CLCN7 gene are associated with diverse forms of osteopetrosis. The functional evaluation of ClC-7 variants might be informative with respect to their pathogenicity, but the cellular localization of the protein hampers this analysis. Here we investigated the functional effects of 13 CLCN7 mutations identified in 13 new patients with severe or mild osteopetrosis and a known ADO2 mutation. We mapped the mutated amino acid residues in the homology model of ClC-7 protein, assessed the lysosomal colocalization of ClC-7 mutants and Ostm1 through confocal microscopy, and performed patch-clamp recordings on plasma-membrane-targeted mutant ClC-7. Finally, we analyzed these results together with the patients' clinical features and suggested a correlation between the lack of ClC-7/Ostm1 in lysosomes and severe neurodegeneration. © 2020 American Society for Bone and Mineral Research (ASBMR).


Subject(s)
Bone Resorption , Osteopetrosis , Animals , Chloride Channels/genetics , Humans , Lysosomes , Mice , Mutation/genetics , Osteoclasts , Osteopetrosis/genetics
18.
Biotechnol Lett ; 32(6): 811-6, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20155387

ABSTRACT

Tensioactive properties of rhamnolipids produced by a Pseudomonas aeruginosa strain were investigated in the presence or absence of Sr(2+) or Pb(2+). Surface and interfacial properties, and aggregate forming properties and morphologies were studied by various techniques including scanning electron microscopy. When the pH of a rhamnolipid aqueous solution (40 mg/l) was increased from 5 to 8, irregular vesicles gradually took the shape of oligo-vesicles, then regular vesicles and finally smaller spherical vesicles. Addition of metal ions controlled the aggregates' morphology and stability, and influenced the surface and interfacial behavior of rhamnolipid solutions.


Subject(s)
Glycolipids/chemistry , Glycolipids/metabolism , Pseudomonas aeruginosa/metabolism , Surface-Active Agents/chemistry , Surface-Active Agents/metabolism , Cations, Divalent/metabolism , Hydrogen-Ion Concentration , Lead/metabolism , Microscopy, Electron, Scanning , Strontium/metabolism , Surface Properties
19.
Article in English | MEDLINE | ID: mdl-32899902

ABSTRACT

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Hyperinflation of the lungs leads to a remodeling of the inspiratory muscles that causes postural deformities and more labored breathing. Postural changes include elevated, protracted, or abducted scapulae with medially rotated humerus, and kyphosis that leads to further tightening of respiratory muscles. As the severity of the disease progresses, use of the upper limbs for functional tasks becomes difficult due to muscle stiffness. There are various studies that suggest different rehabilitation programs for COPD patients; however, to the best of our knowledge none recommends passive stretching techniques. The aim of this study was to assess the effect of respiratory muscle passive stretching on chest expansion and 6-min walk distance (6MWD) in patients with moderate to severe COPD. METHODS: Thirty patients were divided into two groups, experimental (n = 15) and control (n = 15). The experimental group received a hot pack followed by stretching of the respiratory muscles and relaxed passive movements of the shoulder joints. The control group received a hot pack followed by relaxed passive movements of the shoulder joints. RESULTS: In the control group, there was no difference in chest expansion at the levels of both the axilla and the xiphisternum or in 6MWD between baseline and post treatment (p > 0.05). In the experimental group, chest expansion at the level of the axilla (p < 0.05) and 6MWD (p < 0.001) were significantly higher post treatment, while there was no difference in chest expansion at the level of the xiphisternum (p > 0.05). A comparison between control and experimental groups showed that chest expansion at the level of the axilla (p < 0.05) and 6MWD (p < 0.01) were significantly higher in the experimental group, while there was no difference in chest expansion at the level of the xiphisternum (p > 0.05). CONCLUSIONS: Although COPD is an irreversible disease, results of this study indicate that passive stretching of respiratory muscles can clinically improve the condition of such patients, especially in terms of chest expansion and 6MWD. Given the good effects of muscle stretching and the fact that such an exercise is harmless, clinicians and physiotherapists should consider including passive stretching of respiratory muscles in the rehabilitation plan of COPD patients.


Subject(s)
Lung/physiopathology , Muscle Stretching Exercises , Pulmonary Disease, Chronic Obstructive/therapy , Respiratory Muscles/physiopathology , Adult , Exercise Tolerance , Female , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/diagnosis , Respiratory Muscles/physiology , Treatment Outcome
20.
J Nanosci Nanotechnol ; 20(12): 7618-7628, 2020 12 01.
Article in English | MEDLINE | ID: mdl-32711634

ABSTRACT

The emergence of bacterial resistance to currently available antibiotics emphasized the urgent need for new antibacterial agents. Nanotechnology-based approaches are substantially contributing to the development of effective and better-formulated antibiotics. Here, we report the synthesis of stable manganese oxide nanostructures (MnO NS) by a facile, one-step, microwave-assisted method. Asprepared MnO NS were thoroughly characterized by atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), UV-Visible spectroscopy and X-ray powder diffraction (XRD). UV-Visible spectra give a sharp absorption peak at a maximum wavelength of 430 nm showed surface plasmon resonance (SPR). X-ray diffraction (XRD) profile demonstrated pure phase and crystalline nature of nanostructures. Morphological investigations by a scanning electron microscope showed good dispersity with spherical particles possessing a size range between 10-100 nm. Atomic force microscope data exhibited that the average size of MnO NS can be controlled between 25 nm to 150 nm by a three-fold increment in the amount of stabilizer (o-phenylenediamine). Antimicrobial activity of MnO NS on both gram-positive (Bacillus subtilis) and gram-negative (Escherichia coli) bacterial strains showed that prepared nanostructures were effective against microorganisms. Further, this antibacterial activity was found to be dependent on nanoparticles (NPs) size and bacterial species. These were more effective against Bacillus subtilis (B. subtilis) as compared to Escherichia coli (E. coli). Considering the results together, this study paves the way for the formulation of similar nanostructures as effective antibiotics to kill other pathogens by a more biocompatible platform. This is the first report to synthesize the MnO NS by green approach and its antibacterial application.


Subject(s)
Metal Nanoparticles , Nanostructures , Anti-Bacterial Agents/pharmacology , Escherichia coli , Manganese Compounds , Microbial Sensitivity Tests , Oxides , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
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