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1.
J Insect Sci ; 23(6)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38159032

RESUMEN

The rice weevil, Sitophilus oryzae (Linnaeus, Coleoptera: Curculionidae), is a serious cosmopolitan pest that affects grain in storage and has developed high levels of resistance toward phosphine. In this study, RNA-seq data was used to study the phosphine resistance mechanisms in S. oryzae. Resistant and susceptible populations of S. oryzae were identified based on phosphine bioassays conducted in 32 populations collected across Tamil Nadu, India. Differential expression of mitochondrial (COX1, COX2, COX3, ND2, ND3, ATP6, and ATP8) and detoxification genes (Cyps, Gsts, and Cbe) were observed in the resistant and susceptible populations of S. oryzae. The previously characterized phosphine resistant gene, dld (dihydrolipoamide dehydrogenase) linked to the rph2 locus, was found to be up-regulated in resistant S. oryzae population (ISO-TNAU-RT) treated with phosphine. Also, the genes involved in Tricarboxylic acid (TCA) cycle were significantly down-regulated. In addition, a significant up-regulation in the expression of the antioxidant enzymes superoxide dismutase (2.5×) and catalase (2.1×) in ISO-TNAU-RT populations was recorded. Furthermore, a distinct amino acid substitution, Lysine > Glutamic acid (K141E) was identified in resistant phenotypes. In silico docking studies of both resistant and susceptible DLD protein with phosphine molecule revealed that the amino acid residues involved in the interaction were different. This suggested that the amino acid substitution might lead to structural modifications which reduces the affinity of the target (phosphine). This study provides insight on the various genes, pathways, and functional mechanisms having a significant role in phosphine resistance in S. oryzae.


Asunto(s)
Escarabajos , Insecticidas , Gorgojos , Animales , Escarabajos/genética , Gorgojos/genética , India , Insecticidas/farmacología , Resistencia a los Insecticidas/genética , Perfilación de la Expresión Génica
2.
Behav Pharmacol ; 30(8): 689-699, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31703031

RESUMEN

Loss of midbrain dopaminergic neurons in Parkinson's disease not only induces motor impairments but also leads to the development of non-motor symptoms such as memory impairment, anxiety and depression. Dopaminergic axons directly innervate hippocampus and release dopamine in the local environment of hippocampus, and hence are directly involved in the modulation of hippocampal-dependent functions. Studies have explored the potential effect of dopamine on adult hippocampal neurogenesis. However, it is not well defined whether oxidative damage and inflammation could be associated with alteration in adult hippocampal neurogenesis. In the present study, we analyzed the effect of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine on adult hippocampal neurogenesis and how it is associated with inflammatory conditions in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease-like phenotypes. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice exhibited significantly reduced dopaminergic neurons and dopamine content that resulted in impairment of motor functions. Interestingly, the formation of endogenous neuronal precursor cells and the number of neuroblasts in the hippocampus were significantly increased following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment. Net hippocampal neurogenesis was also reduced in the hippocampus after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine treatment. These effects in the hippocampus were associated with increased oxidative stress markers and a massive reactive gliosis. Taken together, our results suggest that degeneration of midbrain dopaminergic neurons directly affects the local hippocampal microenvironment by enhancing inflammatory influences. The 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced inflammatory reaction in the hippocampus may alter the endogenous regenerative capacity of the brain. Therefore, anti-inflammatory agents could be a potential therapy for the improvement of the endogenous regenerative capacity of the aging or neurodegenerative brain.


Asunto(s)
Neurogénesis/efectos de los fármacos , Neuroinmunomodulación/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Animales , Encéfalo/efectos de los fármacos , Modelos Animales de Enfermedad , Dopamina , Neuronas Dopaminérgicas/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neurogénesis/fisiología , Neuroinmunomodulación/fisiología , Estrés Oxidativo/fisiología , Enfermedad de Parkinson , Sustancia Negra/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo
3.
J Med Syst ; 43(3): 55, 2019 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-30694396

RESUMEN

Gait analysis is considered as the most systematic study of human motion. The analysis of gait includes visual and analytical perception of the individual, augmentation of various mechanical instrumentations for measuring movement of body, muscles activity and body mechanics. Past study focused on gait analysis of various animal locomotion and humans mainly on sports biomechanics. This paper aims to quantify the gait performance with Jaipur Knee, which is one of the most widely used prosthesis in Indian population. Gait data with Jaipur knee joint is not available till date. The proposed study targets to predict the performance of Jaipur knee joint in terms of gait symmetry with transfemoral Indian amputees. Gait symmetry may be the basis of recommendation of knee joint to prosthetic patients. This study used kinematics and kinetics parameters together to quantify the performance of Jaipur knee joint to evaluate gait symmetry. This research will be helpful for clinician to predict and further to prevent the degenerated musculoskeletal effects generally seen in unilateral transfemoral amputees.


Asunto(s)
Amputados/rehabilitación , Miembros Artificiales , Marcha/fisiología , Articulación de la Rodilla/fisiología , Pierna/fisiología , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Rango del Movimiento Articular
4.
BMC Complement Altern Med ; 18(1): 69, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29463254

RESUMEN

BACKGROUND: Spinacia oleracea is an important dietary vegetable in India and throughout the world and has many beneficial effects. It is cultivated globally. However, its effect on osteoarthritis that mainly targets the cartilage cells remains unknown. In this study we aimed to evaluate the anti-osteoarthritic and chondro-protective effects of SOE on chemically induced osteoarthritis (OA). METHODS: OA was induced by intra-patellar injection of monosodium iodoacetate (MIA) at the knee joint in rats. SOE was then given orally at 250 and 500 mg.kg- 1 day- 1 doses for 28 days to these rats. Anti-osteoarthritic potential of SOE was evaluated by micro-CT, mRNA and protein expression of pro-inflammatory and chondrogenic genes, clinically relevant biomarker's and behavioural experiments. RESULTS: In vitro cell free and cell based assays indicated that SOE acts as a strong anti-oxidant and an anti-inflammatory agent. Histological analysis of knee joints at the end of the experiment by safranin-o and toluidine blue staining established its protective effect. Radiological data corroborated the findings with improvement in the joint space and irregularity of the articular and atrophied femoral condyles and tibial plateau. Micro-CT analysis of sub-chondral bone indicated that SOE had the ability to mitigate OA effects by increasing bone volume to tissue volume (BV/TV) which resulted in decrease of trabecular pattern factor (Tb.Pf) by more than 200%. SOE stimulated chondrogenic marker gene expression with reduction in pro-inflammatory markers. Purified compounds isolated from SOE exhibited increased Sox-9 and Col-II protein expression in articular chondrocytes. Serum and urine analysis indicated that SOE had the potential to down-regulate glutathione S-transferase (GST) activity, clinical markers of osteoarthritis like cartilage oligometric matrix protein (COMP) and CTX-II. Overall, this led to a significant improvement in locomotion and balancing activity in rats as assessed by Open-field and Rota rod test. CONCLUSION: On the basis of in vitro and in vivo experiments performed with Spinacea oleracea extract we can deduce that SOE has the ability to alleviate the MIA induced deleterious effects.


Asunto(s)
Osteoartritis/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Spinacia oleracea/química , Animales , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , India , Yodoacetatos/efectos adversos , Articulación de la Rodilla/efectos de los fármacos , Articulación de la Rodilla/metabolismo , Articulación de la Rodilla/patología , Osteoartritis/inducido químicamente , Osteoartritis/genética , Osteoartritis/metabolismo , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Tibia/efectos de los fármacos , Tibia/metabolismo , Tibia/patología
5.
Cureus ; 16(8): e67092, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39286669

RESUMEN

The cause of sarcoidosis is unknown, and it affects multiple systems with granulomas. Lung lesions are typical, but extrapulmonary findings, especially lymphadenopathy, are present in a significant number of cases. Isolated renal involvement is rare. The presence of noncaseating granulomas on biopsy is a hallmark of sarcoidosis. We present the case of a 59-year-old male with recurrent renal stones who presented with renal failure. The initial diagnosis was challenging due to normal chest imaging and no pulmonary involvement. However, his delayed presentation of calcinosis cutis, an increase in angiotensin-converting enzyme (ACE) level, and the biopsy of the palm lesion with noncaseating granulomas helped us reach the diagnosis. He was started on prednisolone and achieved remission. The report also intends to show that patients with sarcoidosis can present without lung involvement, and physicians should consider sarcoidosis as their differential diagnosis for idiopathic hypercalcemia even if it has no lung or skin findings.

6.
Int J Biol Macromol ; 278(Pt 2): 134608, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39134192

RESUMEN

The avascular nature of cartilage tissue limits inherent regenerative capacity to counter any damage and this has become a substantial burden to the health of individuals. As a result, there is a high demand to repair and regenerate cartilage. Existing tissue engineering approaches for cartilage regeneration typically produce either microporous or nano-fibrous scaffolds lacking the desired biological outcome due to lack of biomimetic dual architecture of microporous construct with nano-fibrous interconnected structures like the native cartilage. Most of these scaffolds also fail to suppress ROS generation and provide sustained bioenergetics to cells, resulting in the loss of metabolic activity under avascular microenvironment of cartilage. A dual architecture microporous construct with nano-fibrous interconnected network of cellulose aerogel reinforced with arginine-coated graphene oxide (CNF-GO-Arg aerogel) was developed for cartilage regeneration. The designed dual-architectured CNF-GO-Arg aerogel using dual ice templating assembly demonstrates 80 % strain recovery ability under compression. The release of Arginine from CNF-GO-Arg aerogel supported 41 % reduction in intracellular ROS activity and promoted chondrogenic differentiation of hMSCs by shifting mitochondrial bioenergetics towards oxidative phosphorylation indicated by JC-1 dye staining. Overall developed CNF-GO-Arg aerogel provided multifunctionality via biomimetic morphology, cellular bioenergetics, and suppressed ROS generation to address the need for regeneration of cartilage.


Asunto(s)
Arginina , Cartílago , Celulosa , Grafito , Andamios del Tejido , Celulosa/química , Celulosa/farmacología , Grafito/química , Grafito/farmacología , Humanos , Andamios del Tejido/química , Arginina/química , Arginina/farmacología , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Ingeniería de Tejidos/métodos , Metabolismo Energético/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Especies Reactivas de Oxígeno/metabolismo , Condrogénesis/efectos de los fármacos , Geles/química , Regeneración/efectos de los fármacos , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología
7.
Cureus ; 16(6): e63385, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39070506

RESUMEN

Gemcitabine-induced thrombotic microangiopathy (GITMA) is a rare but severe complication seen in cancer patients on gemcitabine therapy. This case report describes a 45-year-old female with metastatic cholangiocarcinoma on gemcitabine-capecitabine who developed acute kidney injury and hypertension without typical hematologic signs of thrombotic microangiopathy (TMA). Despite initial management targeting hypertensive urgency and acute kidney injury, renal function continued to decline and progressed to end-stage renal disease requiring hemodialysis. Laboratory tests revealed TMA features such as elevated lactate dehydrogenase (LDH), decreased haptoglobin, and schistocytes. Renal biopsy confirmed TMA with chronic features. This case highlights the challenge of diagnosing drug-induced TMA without typical hematologic findings.

8.
ACS Appl Bio Mater ; 7(5): 3096-3109, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38764432

RESUMEN

Wire arc additive manufacturing (WAAM) holds promise for producing medium to large industrial components. Application of WAAM in the manufacturing of biomedical materials has not yet been evaluated. The current study addresses two key research questions: first, the suitability of the WAAMed Ti6Al4V alloy for biomedical applications, and second, the effect of Ti6Al4V's constituents (α and ß phases) on the cell viability. The WAAMed Ti6Al4V alloy was fabricated (as-deposited: AD) using a metal inert gas (MIG)-based wire arc system using an in-house designed shielding chamber filled with argon. Subsequently, samples were subjected to solution treatment (950 °C for 1 h), followed by aging at 480 °C (T1), 530 °C (T2), and 580 °C (T3) for 8 h and subsequent normalization to ambient conditions. Microstructural analysis revealed ∼45.45% of α'-Ti colonies in the as-deposited samples, reducing to 23.26% postaging at 580 °C (T3). The α-lath thickness and interstitial oxygen content in the sample were observed to be proportional to the aging temperature, peaking at 580 °C (T3). Remarkably, during tribocorrosion analysis in simulated body fluid, the 580 °C-aged T3 sample displayed the lowest corrosion rate (7.9 µm/year) and the highest coefficient of friction (CoF) at 0.58, showing the effect of increasing oxygen content in the alloy matrix. Cell studies showed significant growth at 530 and 580 °C by day 7, correlated with higher oxygen content, while other samples had declining cell density. Additionally, optimal metallurgical property ranges were identified to enhance the Ti6Al4V alloy's biocompatibility, providing crucial insights for biomedical implant development.


Asunto(s)
Aleaciones , Materiales Biocompatibles , Supervivencia Celular , Calor , Ensayo de Materiales , Titanio , Titanio/química , Aleaciones/química , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Animales , Tamaño de la Partícula , Ratones , Propiedades de Superficie
9.
Biomater Adv ; 157: 213730, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38101066

RESUMEN

The incapability of cartilage to naturally regenerate and repair chronic muscular injuries urges the development of competent bionic rostrums. There is a need to explore faster strategies for chondrogenic engineering using mesenchymal stem cells (MSCs). Along these lines, rapid chondrocyte differentiation would benefit the transplantation demand affecting osteoarthritis (OA) and rheumatoid arthritis (RA) patients. In this report, a de novo nanocomposite was constructed by integrating biogenic carbon quantum dot (CQD) filler into synthetic hydrogel prepared from dimethylaminoethyl methacrylate (DMAEMA) and acrylic acid (AAc). The dominant structural integrity of synthetic hydrogel along with the chondrogenic differentiation potential of garlic peel derived CQDs led to faster chondrogenesis within 14 days. By means of extensive chemical and morphological characterization techniques, we illustrate that the hydrogel nanocomposite possesses lucrative features to influence rapid chondrogenesis. These results were further corroborated by bright field imaging, Alcian blue staining and Masson trichome staining. Thus, this stratagem of chondrogenic engineering conceptualizes to be a paragon in clinical wound care for the rapid manufacturing of chondrocytes.


Asunto(s)
Puntos Cuánticos , Humanos , Nanogeles , Condrogénesis , Cartílago , Hidrogeles
10.
Curr Alzheimer Res ; 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37282567

RESUMEN

AIMS: Caffeine possesses potent antioxidant, anti-inflammatory and anti-apoptotic activities against a variety of neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). The goal of this study was to investigate the protective role of a psychoactive substance like caffeine on hippocampal neurogenesis and memory functions in streptozotocin (STZ)-induced neurodegeneration in rats. BACKGROUND: Caffeine is a natural CNS stimulant, belonging to the methylxanthine class, and is a widely consumed psychoactive substance. It is reported to abate the risk of various abnormalities that are cardiovascular system (CVS) related, cancer related, or due to metabolism dysregulation. Short-term caffeine exposure has been widely evaluated, but its chronic exposure is less explored and pursued. Several studies suggest a devastating role of caffeine in neurodegenerative disorders. However, the protective role of caffeine on neurodegeneration is still unclear. OBJECTIVE: Here, we examined the effects of chronic caffeine administration on hippocampal neurogenesis in intracerebroventricular STZ injection induced memory dysfunction in rats. The chronic effect of caffeine on proliferation and neuronal fate determination of hippocampal neurons was evaluated by co-labeling of neurons by thymidine analogue BrdU that labels new born cells, DCX (a marker for immature neurons) and NeuN that labels mature neurons. METHOD: STZ (1 mg/kg, 2 µl) was injected stereotaxically into the lateral ventricles (intracerebroventricular injection) once on day 1, followed by chronic treatment with caffeine (10 mg/kg, i.p) and donepezil (5 mg/kg, i.p.). Protective effect of caffeine on cognitive impairment and adult hippocampal neurogenesis was evaluated. RESULT: Our findings show decreased oxidative stress burden and amyloid burden following caffeine administration in STZ lesioned SD rats. Further, double immunolabeling with bromodeoxyuridine+/doublecortin+ (BrdU+/DCX+) and bromodeoxyuridine+/ neuronal nuclei+ (BrdU+/NeuN+) has indicated that caffeine improved neuronal stem cell proliferation and long term survival in STZ lesioned rats. CONCLUSION: Our findings support the neurogenic potential of caffeine in STZ induced neurodegeneration.

11.
ACS Chem Neurosci ; 14(12): 2271-2281, 2023 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-37261380

RESUMEN

The functional and developmental unit of neurogenesis is neural stem cells (NSCs). These NSCs have self-renewal capacity and produce new neurons throughout life in different neurogenic niche. Neurogenesis in adult brain is associated with synaptic plasticity, learning, and memory in dentate gyrus (DG) of hippocampus and olfactory bulb. Remarkably, weakened neurogenesis has been viewed before the onset of different pathological hallmarks of neurological disorders. In this review, we have provided evidence which implicates impaired neurogenesis as a culprit in age associated neurological disorders with greater emphasis on Alzheimer's disease (AD). Moreover, an insight about the molecular and cellular regulation linked with altered neurogenesis in young and aging brain has also been discussed. This review further summarizes the therapeutic strategies for targeting the manipulation of the neural stem cell pool and factors affecting the pool involved in AD.


Asunto(s)
Enfermedad de Alzheimer , Células-Madre Neurales , Adulto , Humanos , Enfermedad de Alzheimer/patología , Hipocampo/patología , Células-Madre Neurales/fisiología , Neurogénesis/fisiología , Neuronas/patología
12.
ACS Biomater Sci Eng ; 9(10): 5900-5911, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37702616

RESUMEN

The ability of bone to regenerate itself through mechanobiological responses is its dynamic property. Mechanical cues from a neighboring environment produce the structural strain to promote blood flow and bone marrow mobility that in turn aids the bone regeneration process. Occurrences of these phenomena are crucial for the success of metallic scaffolds implanted in the host bone tissue. Thus, permeability and fluid flow-induced wall shear stress (WSS) are two parameters that directly influence cell bioactivities inside a scaffold and are crucial for effective bone tissue regeneration. Given that the scaffolds shall be implanted in the body, permeability assessment was carried out using non-Newtonian fluid. In this work, the triply periodic minimal surface scaffolds with Neovius architectures were fabricated by using selective laser melting technology. The estimation of fluid flow was carried out using computational fluid dynamics (CFD) analysis with a non-Newtonian blood fluid model. Further, the structural strength of various open cell Neovius lattices was evaluated using a static compression test, and in vitro cell culture using Alamar blue assay was evaluated. Results revealed that the values of intrinsic blood flow permeability of the three-dimensional (3D)-printed open cell porous scaffold with Neovius architecture were of the same order of magnitude as those of human bone, ranging from 0.0025 × 10-9 to 0.0152 × 10-9 m2. The structural elastic modulus and compressive strength of NOCL40, NOCL50, and NOCL60 lattices range from 3.27 to 3.71 GPa and 194 to 205 MPa, respectively. All of the values are comparable to the human bone, thus making these lattices a suitable alternative for orthopedic applications.

13.
Eur J Pharmacol ; 946: 175623, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36871666

RESUMEN

Activation of the renin-angiotensin system (RAS), by Angiotensin converting enzyme/Angiotensin II/Angiotensin receptor-1 (ACE/Ang II/AT1 R) axis elicits amyloid deposition and cognitive impairment. Furthermore, ACE2 induced release of Ang-(1-7) binds with the Mas receptor and autoinhibits ACE/Ang II/AT1 axis activation. Inhibition of ACE by perindopril has been reported to improve memory in preclinical settings. However, the functional significance and mechanism by which ACE2/Mas receptor regulate cognitive functions and amyloid pathology is not known. The present study is aimed to determine the role of ACE2/Ang-(1-7)/Mas receptor axis in STZ induced rat model of Alzheimer's disease (AD). We have used pharmacological, biochemical and behavioural approaches to identify the role of ACE2/Ang-(1-7)/Mas receptor axis activation on AD-like pathology in both in vitro and invivo models. STZ treatment enhances ROS formation, inflammation markers and NFκB/p65 levels which are associated with reduced ACE2/Mas receptor levels, acetylcholine activity and mitochondrial membrane potential in N2A cells. DIZE mediated ACE2/Ang-(1-7)/Mas receptor axis activation resulted in reduced ROS generation, astrogliosis, NFκB level and inflammatory molecules and improved mitochondrial functions along with Ca2+ influx in STZ treated N2A cells. Interestingly, DIZE induced activation of ACE2/Mas receptor significantly restored acetylcholine levels and reduced amyloid-beta and phospho-tau deposition in cortex and hippocampus that resulted in improved cognitive function in STZ induced rat model of AD-like phenotypes. Our data indicate that ACE2/Mas receptor activation is sufficient to prevented cognitive impairment and progression of amyloid pathology in STZ induced rat model of AD-like phenotypes. These findings suggest the potential role of ACE2/Ang-(1-7)/Mas axis in AD pathophysiology by regulating inflammation cognitive functions.


Asunto(s)
Enfermedad de Alzheimer , Ratas , Animales , Enfermedad de Alzheimer/patología , Estreptozocina , Enzima Convertidora de Angiotensina 2/genética , Especies Reactivas de Oxígeno , Acetilcolina , Peptidil-Dipeptidasa A/metabolismo , Cognición , Inflamación/tratamiento farmacológico , Fenotipo , Fragmentos de Péptidos/farmacología , Angiotensina I/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Angiotensina II/farmacología
14.
Adv Med Educ Pract ; 13: 543-554, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651479

RESUMEN

Introduction: Experiencing is essential to learning anything in life. Medical educators across the world aim at achieving profound learning experiences for their students. Several applications of experiential learning into health professions education have been witnessed over the past two decades. Though many researchers have tried to implement authentic learning experiences in medical education, only a handful have been able to demonstrate its effectiveness in anatomical sciences education. In this study, the authors asked the question - Can experiential learning-based dissection hall sessions be innovated to improve the contextual learning of anatomical sciences during early clinical exposure? Methods: Three experiential learning theory (ELT)-based sessions were conducted. Perceptions from faculty and students were collected. Results: The satisfaction index of the students' perception of the ELT based sessions was of 96.1% and for faculty was 100%. The emergent facilitating factors in the learning process were found to be: more profound and interactive contextual learning experience; improved problem-solving approaches based on dominant skill activities of dissection hall; and learning experiences created to cater to different learning needs of students. The optimal facilitator to student ratio range suggested for these sessions was 1:10 to 1:15. Discussion: The faculties were motivated to utilize this learning experience to further research teaching innovations at the present institution. Experiential learning-based sessions applied to anatomical sciences education can effectively foster positive student engagement and profound learning experience.

15.
Biomed Mater ; 17(4)2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35447615

RESUMEN

Site-specific drug delivery has the potential to reduce drug dosage by 3- to 5-folds. Given the propensity of drugs used in the treatment of tuberculosis and cancers, the increased drug dosages via oral ingestion for several months to a few years of medication is often detrimental to the health of patients. In this study, the sustained delivery of drugs with multiscale structured novel Neovius lattices was achieved. 3D Neovius open cell lattices (NOCL) with porosities of 40%, 45%, and 50% were fabricated layer-by-layer on the laser bed fusion process. Micron-sized Ti6Al4V ELI powder was used for 3D printing. The Young's modulus achieved from the novel Neovius lattices were in the range of 1.2-1.6 GPa, which is comparable to human cortical bone and helps to improve implant failure due to the stress shielding effect. To provide sustained drug delivery, nanotubes (NTs) were fabricated on NOCLs via high-voltage anodization. The osteogenic agent icariin was loaded onto the NOCL-NT samples and their release profiles were studied for 7 d. A significantly steady and slow release rate of 0.05% per hour of the drug was achieved using NOCL-NT. In addition, the initial burst release of NOCL-NT was 4 fold lower than that of the open-cell lattices without NTs. Cellular studies using MG63 human osteoblast-like cells were performed to determine their biocompatibility and osteogenesis which were analyzed using Calcein AM staining and Alamar Blue after 1, 5, and 7 d. 3D printed NOCL samples with NTs and with Icariin loaded NTs demonstrated a significant increase in cell proliferation as compared to as printed NOCL samples.


Asunto(s)
Aleaciones , Nanotubos , Humanos , Osteogénesis , Porosidad , Impresión Tridimensional , Titanio/química
16.
Rev Sci Instrum ; 92(11): 114710, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34852519

RESUMEN

A rapid, high voltage capacitor charging power supply (CCPS) based on a third order resonant converter topology has been proposed, analyzed, and simulated using the PSpice software, and as a proof of concept, a prototype of the 6.0 kV, 6.0 A CCPS is also developed. High charging power, low resonant current, and high pulse repetition rate were targeted in the design. In this paper, ac analysis for the calculation of impedance and resonant frequency, and frequency dependence on current gain, and the steady state analysis of the proposed scheme have been studied and presented. The performance is analyzed by simulating the circuit for two values of load capacitances. The simulation and prototype results show linear charging of the load for both values of load capacitances. The charging times of 1.47 and 0.97 ms have been achieved for load capacitances of 1.5 and 1.0 µF, respectively. The performance of the LLC topology has been compared with a conventionally used series resonant scheme. A high charging power of 18.4 kJ/s has been achieved. The topology shows a faster charging rate by ∼36% in comparison with the series LC resonant topology. The results of the analysis match with the simulation and prototype results, which confirms that the proposed scheme is suitable for rapid and reliable CCPS applications.

17.
Pest Manag Sci ; 77(7): 3289-3299, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33763965

RESUMEN

BACKGROUND: The rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) is a cosmopolitan pest of stored cereal grains and other commodities globally. Infestations caused by S. oryzae makes grains unsuitable for consumption, processing, and export. Deltamethrin, a synthetic pyrethroid insecticide, is widely used in major grain storages in India as a prophylactic treatment to control this pest. However, recurrent use of this insecticide had led to genetic resistance in S. oryzae, questioning its ongoing use at the current recommended concentration. RESULTS: Dose response analysis of resistant (Delta-R) and susceptible (Lab-S) strains of S. oryzae collected from grain storages across southern India, revealed that Delta-R was 134-fold more resistant than the Lab-S at median lethal concentration (LC50 ). A concentration of 180 ppm over 48 h effectively discriminated 16 resistant field populations from Lab-S with per cent resistance ranging from 8.72% to 75.86%. Exposing all the resistant populations to 1000 ppm over 48 h identified 12 populations with strongly resistant individuals and confirmed the existence of two distinct resistance phenotypes, 'weak' and 'strong' in S. oryzae. Furthermore, sequence analysis of the voltage-gated sodium channel (vgsc) gene in Delta-R identified a single target site mutation, T929I conferring resistance in S. oryzae. CAPS (Cleaved Amplified Polymorphic Sequence) marker analysis of this allele confirmed that frequency of resistance is high (up to 0.96) supporting the results of phenotypic analysis. CONCLUSION: Both phenotype and molecular marker analyses clearly demonstrated that deltamethrin at 180 and 1000 ppm can be used to discriminate weakly and strongly resistant populations in S. oryzae, respectively. Resistance diagnostics based on the mutation, T929I, supports our phenotypic data and indicates that resistance to deltamethrin in S. oryzae is prevalent in southern parts of India, stressing the need to identify a synergist or suitable alternatives. © 2021 Society of Chemical Industry.


Asunto(s)
Resistencia a los Insecticidas , Insecticidas , Piretrinas , Canales de Sodio Activados por Voltaje/genética , Gorgojos , Animales , India , Proteínas de Insectos/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mutación , Nitrilos , Fenotipo , Piretrinas/farmacología , Gorgojos/genética
18.
Brain Res ; 1754: 147261, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33422534

RESUMEN

Antidepressants are well known to exert their role via upregulation of brain derived neurotrophic factor (BDNF). BDNF has been reported to exerts its neuroprotective effect in rodent and primate models as well as in patients of Alzheimer's disease (AD). The aim of our study was to evaluate the effect of protriptyline (PRT), a tricyclic antidepressant, in streptozotocin (STZ)- induced rat model of AD. Total 10 µl of STZ was injected into each ventricle (1 mg/kg). PRT (10 mg/kg, i.p.) treatment was started 3-day post STZ administration and continued till 21 days. We found that STZ treatment significantly increased pTau, Aß42 and BACE-1 expression, oxidative stress and neurodegeneration in hippocampus and cortex of adult rats. STZ induced impairment in spatial learning and retention memory was associated with increased NFκB and reduced CREB and BDNF expression in cortex and hippocampus. Interestingly, PRT treatment significantly reduced pTau, Aß42 and BACE-1 levels, neurodegeneration, oxidative stress and glial activation, contributing to the improved spatial learning and retention memory in STZ treated rats. Moreover, PRT treatment significantly improved p-ERK/ERK ratio and enhanced BDNF and CREB levels by reducing NFκB and GFAP expression in STZ treated rats. Our data suggest that impaired NFκB and CREB signaling potentially contribute in AD pathogenesis by elevating oxidative stress and neuroinflammation mediated neurodegeneration. Our study has established protriptyline as a multi target molecule in pre-clinical model of AD and further investigations on PRT like molecules could pave way for further development of effective new treatments in neurodegenerative disorders.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Protriptilina/farmacología , Memoria Espacial/efectos de los fármacos , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/metabolismo , Fármacos Neuroprotectores/farmacología , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Estreptozocina/farmacología
19.
Brain Res Bull ; 172: 164-179, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33895271

RESUMEN

Psychological and physical stress play a pivotal role in etiology of anxiety and depression. Chronic psychological and physical stress modify various physiological phenomena, as a consequence of which oxidative stress, decreased neurotransmitter level, elevated corticosterone level and altered NSC homeostasis is observed. However, the precise mechanism by which chronic stress induce anxious depression and modify internal milieu is still unknown. Herein, we show that exposure to CUS increase oxidative stress, microgliosis, astrogliosis while it reduces hippocampal NSC proliferation, neuronal differentiation and maturation in adult rats. CUS exposure in rats reduce dopamine and serotonin level in cortex and hippocampus, which result in increased anxiety and depression-like phenotypes. We also found elevated level of NF-κB and TNF-α while decreased anti-inflammatory cytokine IL-10 level, that led to increased expression of Bax and cleaved Caspase-3 whereas down regulation of antiapoptotic protein Bcl2. Additionally, CUS altered adult hippocampal neurogenesis, increased gliosis and neuronal apoptosis in cerebral cortex and hippocampus which might be associated with reduced AKT and increased ERK signaling, as seen in the rat brain tissue. Taken together, these results indicate that CUS induce oxidative stress and neuroinflammation which directly affects NSC dynamics, monoamines levels and behavioral functions in adult rats.


Asunto(s)
Ansiedad/metabolismo , Apoptosis/fisiología , Depresión/metabolismo , Hipocampo/metabolismo , Neurogénesis/fisiología , Estrés Psicológico/metabolismo , Animales , Conducta Animal/fisiología , Inflamación/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Estrés Oxidativo/fisiología , Ratas , Ratas Sprague-Dawley
20.
Behav Brain Res ; 378: 112304, 2020 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-31626851

RESUMEN

Dopamine (DA) neurotransmitter act on dopamine receptors (D1-D5) to regulate motor functions, reward, addiction and cognitive behavior. The depletion of DA in midbrain due to degeneration of nigral dopaminergic (DAergic) neurons leads to Parkinson's disease (PD). DA agonist and levodopa (L-DOPA) are the only therapies used for symptomatic relief in PD. However, the role of DA receptors in PD pathogenesis and how they are associated with mitochondrial functions and DAergic neurogenesis is still not known. Here, we investigated the mechanistic aspect of DA D1 receptor mediated control of DAergic neurogenesis, motor behavior and mitochondrial functions in rat PD model. The pharmacological activation of D1 receptors markedly improved motor deficits, mitochondrial biogenesis, ATP levels, mitochondrial membrane potential and defended nigral DAergic neurons against 6-hydroxydopamine (6-OHDA) induced neurotoxicity in adult rats. However, the D1 agonist mediated effects were abolished following D1 receptor antagonist treatment in 6-OHDA lesioned rats. Interestingly, pharmacological inhibition of dynamin related protein-1 (Drp-1) by Mdivi-1 in D1 antagonist treated PD rats, significantly restored behavioral deficits, mitochondrial functions, mitochondrial biogenesis and increased the number of newborn DAergic neurons in substantia nigra pars compacta (SNpc). Drp-1 inhibition mediated neuroprotective effects in PD rats were associated with increased level of protein kinase-B/Akt and extracellular-signal-regulated kinase (ERK). Taken together, our data suggests that dopamine D1 receptor mediated reduction in mitochondrial fission and enhanced DAergic neurogenesis may involve Drp-1 inhibition which led to improved behavioral recovery in PD rats.


Asunto(s)
Conducta Animal/efectos de los fármacos , Agonistas de Dopamina/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Dinaminas/efectos de los fármacos , Locomoción/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Biogénesis de Organelos , Enfermedad de Parkinson/tratamiento farmacológico , Receptores de Dopamina D1/agonistas , Animales , Modelos Animales de Enfermedad , Agonistas de Dopamina/administración & dosificación , Antagonistas de Dopamina/farmacología , Dinaminas/antagonistas & inhibidores , Masculino , Oxidopamina/toxicidad , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/antagonistas & inhibidores
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