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2.
J Electr Bioimpedance ; 12(1): 34-49, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34966467

RESUMO

We present here the first impedance-based characterization of the differentiation process of two human mesencephalic fetal neural stem lines. The two dopaminergic neural stem cell lines used in this study, Lund human mesencephalic (LUHMES) and human ventral mesencephalic (hVM1 Bcl-XL), have been developed for the study of Parkinsonian pathogenesis and its treatment using cell replacement therapy. We show that if only relying on impedance magnitude analysis, which is by far the most usual approach in, e.g., cytotoxicity evaluation and drug screening applications, one may not be able to distinguish whether the neural stem cells in a population are proliferating or differentiating. However, the presented results highlight that equivalent circuit analysis can provide detailed information on cellular behavior, e.g. simultaneous changes in cell morphology, cell-cell contacts, and cell adhesion during formation of neural projections, which are the fundamental behavioral differences between proliferating and differentiating neural stem cells. Moreover, our work also demonstrates the sensitivity of impedance-based monitoring with capability to provide information on changes in cellular behavior in relation to proliferation and differentiation. For both of the studied cell lines, in already two days (one day after induction of differentiation) equivalent circuit analysis was able to show distinction between proliferation and differentiation conditions, which is significantly earlier than by microscopic imaging. This study demonstrates the potential of impedance-based monitoring as a technique of choice in the study of stem cell behavior, laying the foundation for screening assays to characterize stem cell lines and testing the efficacy epigenetic control.

3.
Biomed Res Int ; 2021: 9968602, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285920

RESUMO

BACKGROUND: Chemotherapeutic drugs cause severe toxicities if administered unprotected, without proper targeting, and controlled release. In this study, we developed topotecan- (TPT-) loaded solid lipid nanoparticles (SLNs) for their chemotherapeutic effect against colorectal cancer. The TPT-SLNs were further incorporated into a thermoresponsive hydrogel system (TRHS) (TPT-SLNs-TRHS) to ensure control release and reduce toxicity of the drug. Microemulsion technique and cold method were, respectively, used to develop TPT-SLNs and TPT-SLNs-TRHS. Particle size, polydispersive index (PDI), and incorporation efficiency (IE) of the TPT-SLNs were determined. Similarly, gelation time, gel strength, and bioadhesive force studies of the TPT-SLNs-TRHS were performed. Additionally, in vitro release and pharmacokinetic and antitumour evaluations of the formulation were done. RESULTS: TPT-SLNs have uniformly distributed particles with mean size in nanorange (174 nm) and IE of ~90%. TPT-SLNs-TRHS demonstrated suitable gelation properties upon administration into the rat's rectum. Moreover, drug release was exhibited in a control manner over an extended period of time for the incorporated TPT. Pharmacokinetic studies showed enhanced bioavailability of the TPT with improved plasma concentration and AUC. Further, it showed significantly enhanced antitumour effect in tumour-bearing mice as compared to the test formulations. CONCLUSION: It can be concluded that SLNs incorporated in TRHS could be a potential source of the antitumour drug delivery with better control of the drug release and no toxicity.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Lipídeos/química , Substâncias Macromoleculares/química , Nanopartículas/química , Temperatura , Topotecan/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos Nus , Mucosa/efeitos dos fármacos , Mucosa/patologia , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Sprague-Dawley , Reto/efeitos dos fármacos , Reto/patologia , Topotecan/sangue , Topotecan/farmacocinética , Topotecan/farmacologia
4.
Br J Oral Maxillofac Surg ; 59(8): 912-920, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34325943

RESUMO

Dental treatment remains one of the most common reasons for paediatric patients to undergo a general anaesthetic (GA). In addition to a wider scope of practice, oral and maxillofacial (OMF) surgeons are affiliated with this well-reported dentoalveolar surgical burden. Thus far much of the research has shown that the majority of these paediatric GAs are for the treatment of decayed teeth. The aim of this study was to evaluate reasons children in a North London region undergo GA procedures in an OMF department and this population's associated demographic factors. Patients treated by this OMF unit from 2016 to 2017 aged 0-16 were included. Retrospective data was obtained; including age, gender, and ASA physical status. Deprivation was calculated from postcodes using the Index of Multiple Deprivation. Chi squared statistical tests were applied. Data from 600 children undergoing 790 procedures were analysed. A similar number of males and females were treated. The most common age group were the 13-16-year-olds. A total of 89.5% of the patients were ASA I. The greatest surgical burden was simple orthodontic extractions, accounting for 24.4% of all OMF paediatric GA procedures. Deprivation impacted the prevalence of the extraction of carious teeth, soft tissue trauma, and orthodontic-related surgery. In the region studied, more paediatric patients are undergoing GA for orthodontic-related surgery than for the extraction of decayed teeth. The type of facial trauma experienced changes with the age of the child.


Assuntos
Anestesia Dentária , Medicina Estatal , Anestesia Geral , Criança , Feminino , Humanos , Londres/epidemiologia , Masculino , Estudos Retrospectivos , Extração Dentária
5.
Indian J Community Med ; 46(4): 610-613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35068719

RESUMO

INTRODUCTION: Paddy farming is one of the main occupations in Kashmir valley. The workers associated with paddy are exposed to variety of irritants such as manures, fertilizers, and pesticides, besides getting exposed to intense sunlight for long hours due to the nature of their work. All these factors can potentially either trigger skin diseases or can worsen them. AIM: The aim of this study was to find out the prevalence and pattern of various skin disorders among paddy field workers in Kashmir valley. MATERIALS AND METHODS: This was a cross-sectional descriptive study in which 600 workers engaged in paddy farming in different areas of Kashmir valley were screened. The diagnosis was made on clinical grounds and wherever deemed necessary, relevant investigations were carried out to establish the nature of the disease. RESULTS: A total of 600 workers were evaluated for the presence of skin disorders. Two hundred thirty workers (38.3%) were found to have skin lesions, while the rest, i.e. 370 (61.7%) were free from any skin problem. Out of the total skin lesions, infectious ones were seen in 40.4%, while non-infectious accounted for 59.6% cases. The main non-infectious disorders included melasma, followed by hand and foot eczemas, hyperkeratosis of palms and soles and callosities/cuts, while among the infectious group the major chunk was formed by bacterial infections followed by fungal, viral, and parasitic. Pitted keratolysis and intertrigo were the most common bacterial and fungal infections respectively. CONCLUSION: A large number of skin diseases were seen in paddy field workers, with some diseases showing an occupational nature.

6.
Br Dent J ; 229(3): 148, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32811907

Assuntos
Pandemias
7.
Comput Methods Programs Biomed ; 196: 105564, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32535331

RESUMO

This research article proposes an improved Fourier law of heat conduction (Cattaneo-Christov) in presence of heat source/sink. The heat transport characteristics are modeled for mixed convective stagnation point flow by a Riga plate. Flow is generated due to linear stretching velocity. The partial differential system is changed to ordinary differential system through implementing appropriate transformations. Series solutions are developed through semi-analytical method called as homotopy analysis method. Present research article is related to the improved Fourier law of heat conduction (Cattaneo-Christov) over a linear stretchable surface of Riga plate when fluid saturates porous space. The main outcomes of present communication are summarized as: (i) velocity of material particles decreases subject to larger inverse Darcy-number while it enhances via velocity ratio and magnetic parameters (ii) temperature distribution as well as layer thickness enhance for higher estimations of Eckert number and heat source parameter while it decays against Prandtl number (iii) skin friction coefficient decreases through higher values of inverse Darcy number and mixed convection parameter.


Assuntos
Temperatura Alta , Modelos Teóricos , Convecção , Condutividade Térmica , Viscosidade
8.
Br Dent J ; 228(12): 903-904, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32591679
9.
Plant Biol (Stuttg) ; 22(4): 679-690, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32003103

RESUMO

Melatonin has emerged as an essential molecule in plants, due to its role in defence against metal toxicity. Aluminium (Al) and cadmium (Cd) toxicity inhibit rapeseed seedling growth. In this study, we applied different doses of melatonin (50 and 100 µm) to alleviate Al (25 µm) and Cd (25 µm) stress in rapeseed seedlings. Results show that Al and Cd caused toxicity in rapeseed seedling, as evidenced by a decrease in height, biomass and antioxidant enzyme activity. Melatonin increased the expression of melatonin biosynthesis-related Brassica napus genes for caffeic acid O-methyl transferase (BnCOMT) under Al and Cd stress. The genes BnCOMT-1, BnCOMT-5 and BnCOMT-8 showed up-regulated expression, while BnCOMT-4 and BnCOMT-6 were down-regulated during incubation in water. Melatonin application increased the germination rate, shoot length, root length, fresh and dry weight of seedlings. Melatonin supplementation under Al and Cd stress increased superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, proline, chlorophyll and anthocyanin content, as well as photosynthesis rate. Both Cd and Al treatments significantly increased hydrogen peroxide and malondialdehyde levels in rapeseed seedlings, which were strictly counterbalanced by melatonin. Analysis of Cd and Al in different subcellular compartments showed that melatonin enhanced cell wall and soluble fractions, but reduced the vacuolar and organelle fractions in Al- and Cd-treated seedlings. These results suggest that melatonin-induced improvements in antioxidant potential, biomass, photosynthesis rate and successive Cd and Al sequestration play a pivotal role in plant tolerance to Al and Cd stress. This mechanism may have potential implications in safe food production.


Assuntos
Alumínio , Brassica napus , Cádmio , Regulação da Expressão Gênica de Plantas , Melatonina , Alumínio/toxicidade , Antioxidantes/farmacologia , Brassica napus/efeitos dos fármacos , Brassica napus/enzimologia , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Melatonina/farmacologia , Oxirredutases/genética , Oxirredutases/metabolismo , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/crescimento & desenvolvimento , Poluentes do Solo/toxicidade
13.
Clin Exp Dermatol ; 44(4): 414-417, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30284290

RESUMO

Secukinumab is an interleukin (IL)-17 monoclonal antibody inhibiting T-helper (Th)1-mediated immune response. It has proven high efficacy for moderate to severe psoriasis but data on its long-term toxicities are limited. We describe two patients who received secukinumab for clinically presumed psoriasis, but were subsequently diagnosed with mycosis fungoides (MF) following skin biopsies triggered by skin deterioration while on secukinumab. Previous studies suggested decreased numbers of regulatory T cells (Tregs) with increasing stage of MF, which may lead to the shift in the Treg/Th17 balance towards the Th17 pathway. Theoretically, the use of IL-17 monoclonal antibodies to inhibit Th17 pathway may lead to further immunosuppression and disease progression in cutaneous T-cell lymphoma (CTCL) by shifting the balance towards Tregs, although this hypothesis has not been proven. With uncertainty over the role of IL-17 and Treg/Th17 as well as diagnostic challenges in CTCL, we recommend that patients should have a confirmatory skin biopsy prior to the commencement of biologic therapy.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Linfoma Cutâneo de Células T/induzido quimicamente , Psoríase/tratamento farmacológico , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Biópsia , Feminino , Humanos , Interleucina-17 , Linfoma Cutâneo de Células T/patologia , Masculino , Micose Fungoide/patologia , Psoríase/diagnóstico , Psoríase/patologia , Pele/patologia , Neoplasias Cutâneas/patologia , Linfócitos T/efeitos dos fármacos , Células Th17/efeitos dos fármacos
15.
J Dent Res ; 97(9): 977-986, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29863948

RESUMO

In lamellar bone, a network of highly oriented interconnected osteocytes is organized in concentric layers. Through their cellular processes contained within canaliculi, osteocytes are highly mechanosensitive and locally modulate bone remodeling. We review the recent developments demonstrating the significance of the osteocyte lacuno-canalicular network in bone maintenance around implant biomaterials. Drilling during implant site preparation triggers osteocyte apoptosis, the magnitude of which correlates with drilling speed and heat generation, resulting in extensive remodeling and delayed healing. In peri-implant bone, osteocytes physically communicate with implant surfaces via canaliculi and are responsive to mechanical loading, leading to changes in osteocyte numbers and morphology. Certain implant design features allow peri-implant osteocytes to retain a less aged phenotype, despite highly advanced extracellular matrix maturation. Physicochemical properties of anodically oxidized surfaces stimulate bone formation and remodeling by regulating the expression of RANKL (receptor activator of nuclear factor-κB ligand), RANK, and OPG (osteoprotegerin) from implant-adherent cells. Modulation of certain osteocyte-related molecular signaling mechanisms (e.g., sclerostin blockade) may enhance the biomechanical anchorage of implants. Evaluation of the peri-implant osteocyte lacuno-canalicular network should therefore be a necessary component in future investigations of osseointegration to more completely characterize the biological response to materials for load-bearing applications in dentistry and orthopedics.


Assuntos
Materiais Biocompatíveis/farmacologia , Interface Osso-Implante/fisiologia , Implantes Dentários , Osteócitos/efeitos dos fármacos , Animais , Remodelação Óssea/fisiologia , Humanos , Osseointegração/fisiologia , Osteogênese/fisiologia , Propriedades de Superfície
16.
J Mycol Med ; 28(2): 289-293, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29730129

RESUMO

Candida albicans is the most prevalent fungal pathogen in humans. It is the causative agent and most associated with serious fungal infection, accounting for more than 90% of cases. It is a most common cause of deep mycoses and vulvovaginal candidiasis. In the present study we found that methanolic extract of O. sanctum in combination of fluconazole shows higher zone of inhibition and lesser MIC values as compared to methanolic extract of leaves of O. sanctum or fluconazole when used alone. Synergistic antimicrobial activity was found when methanolic extract of leaves of O. sanctum was used in combination with fluconazole against C. albicans azole resistance strains isolated from catheter tip (CT) and high vaginal swab (HVS) (FIC≤0.5). Partial synergistic activity was observed against urine (U). Methanolic extract of stem of O. sanctum in combination with fluconazole gave indifferent antifungal results (FIC=1.0-4.0). Benzene extract of the leaf and stem of O. sanctum in combination with fluconazole showed indifferent antifungal results (FIC=1.0-4.0). Aqueous extract of leaves of O. sanctum in combination with fluconazole showed partial synergistic antimicrobial activity against catheter tip (CT) and high vaginal swab (HVS) and urine (U) (FIC=0.5-1.0). In the present study we evaluate the synergism of C. albicans against azole resistant clinical isolates. This study indicates clear evidence supporting the traditional use of O. sanctum in treating Candida infectious diseases.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica , Fluconazol/farmacologia , Ocimum sanctum/química , Extratos Vegetais/farmacologia , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/microbiologia , Feminino , Humanos , Testes de Sensibilidade Microbiana , Folhas de Planta/química
19.
Mycorrhiza ; 27(4): 383-396, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28066872

RESUMO

Hydrophobins are small secreted proteins that are present as several gene copies in most fungal genomes. Their properties are now well understood: they are amphiphilic and assemble at hydrophilic/hydrophobic interfaces. However, their physiological functions remain largely unexplored, especially within mycorrhizal fungi. In this study, we identified hydrophobin genes and analysed their distribution in eight mycorrhizal genomes. We then measured their expression levels in three different biological conditions (mycorrhizal tissue vs. free-living mycelium, organic vs. mineral growth medium and aerial vs. submerged growth). Results confirmed that the size of the hydrophobin repertoire increased in the terminal orders of the fungal evolutionary tree. Reconciliation analysis predicted that in 41% of the cases, hydrophobins evolved from duplication events. Whatever the treatment and the fungal species, the pattern of expression of hydrophobins followed a reciprocal function, with one gene much more expressed than others from the same repertoire. These most-expressed hydrophobin genes were also among the most expressed of the whole genome, which suggests that they play a role as structural proteins. The fine-tuning of the expression of hydrophobin genes in each condition appeared complex because it differed considerably between species, in a way that could not be explained by simple ecological traits. Hydrophobin gene regulation in mycorrhizal tissue as compared with free-living mycelium, however, was significantly associated with a calculated high exposure of hydrophilic residues.


Assuntos
Proteínas Fúngicas/genética , Duplicação Gênica , Genoma Fúngico , Micorrizas/genética , Genômica , Micélio
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