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Head and neck squamous cancers are very aggressive tumors often diagnosed in late stages with poor prognosis. HNSCCs are usually treated by a course of radiation (IR) therapy and followed by surgery. These treatment regimens fail to bring a complete response. Molecular signatures in tumors are attributed to this response and an improved understanding of the signaling events could offer new avenues for therapy. Here, we show that P21 activated kinase-1 (PAK1) - an oncogenic signaling serine/threonine kinase, is activated upon exposure to IR and this leads to an accelerated tumorigenic character in HNSCC cells. Our results show that PAK1 is highly expressed in HNSCC cell lines, as compared to normal buccal mucosa cells and when HNSCC cells were exposed to IR, they show activated PAK1 and an aggressive phenotype as determined by in vitro functional assays. PAK1 levels were elevated in HNSCC as compared to adjacent normal oral tissues and our results also show convincing evidence of activated PAK1 in patient tumor samples of post- IR treatment as compared to pre-IR treatment and is associated with poor survival. Pak1 Knockout (KO) clones in HNSCC cells showed that they were more sensitive to IR as compared to wild type (wt) cells. This altered sensitivity to IR was attributed to enhanced DNA damage response modulated by PAK1 in cells. Overall, our results suggest that PAK1 expression in HNSCC could be a critical determinant in IR therapy response and silencing PAK1 is likely to be a treatment modality to improve clinical outcomes.
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Neoplasias de Cabeza y Cuello , Quinasas p21 Activadas , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello , Quinasas p21 Activadas/genética , Línea Celular Tumoral , Radiación Ionizante , Neoplasias de Cabeza y Cuello/radioterapiaRESUMEN
Targeting the challenging tumors lacking explicit markers and predictors for chemosensitivity is one of the major impediments of the current cancer armamentarium. Triple-negative breast cancer (TNBC) is an aggressive and challenging molecular subtype of breast cancer, which needs astute strategies to achieve clinical success. The pro-survival B-cell lymphoma 2 (BCL-2) overexpression reported in TNBC plays a central role in deterring apoptosis and is a promising target. Here, we propose three novel BH4 mimetic small molecules, SM396, a covalent binder, and two non-covalent binders, i.e., SM216 and SM949, which show high binding affinity (nM) and selectivity, designed by remodeling the existing BCL-2 chemical space. Our mechanistic studies validate the selectivity of the compounds towards cancerous cells and not on normal cells. A series of functional assays illustrated BCL-2-mediated apoptosis in the tumor cells as a potent anti-cancerous mechanism. Moreover, the compounds exhibited efficacious in vivo activity as single agents in the MDA-MB-231 xenograft model (at nanomolar dosage). Overall, these findings depict SM216, SM396, and SM949 as promising leads, pointing to the clinical translation of these compounds in targeting triple-negative breast cancer.
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Malignant astrocytomas presenting in humans of any age group are a challenge to diagnose and treat. Hence, there is a quest for new markers to ascertain their grades and predict disease outcomes. Proline, glutamic acid, and leucine-rich protein 1 (PELP1), a nuclear receptor co-regulator, is an oncogene found in various cancers. We postulate that by screening for PELP1, its correlation with survival outcomes of patients across various grades can indicate a plausible novel diagnostic marker and a potential therapeutic target in gliomas. Immunostaining of 100 cases of astrocytomas for PELP1 was performed on paraffin-embedded sections. Results showed that PELP1 expression increases with higher grades; the mean H-score of PELP1 in grade-I astrocytomas was determined to be 112.3, whereas in grade-IV it was 235.1 (P value = 0.0001). Survival analysis of patients with H-score of 200-300 was only 8.8% and 68.8% in patients with scores of 0-100. PELP1 expression in high-grade astrocytomas is an important factor in determining the outcomes. Graphical abstract Evaluation of molecular expression of PELP1 along with Ki-67 LI signifies a linear increase in its expression pattern among different grades of astrocytomas from low- to high-grade tumors, which can serve as a potential prognostic molecular marker in differentiating various types of astrocytomas in humans.
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Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Proteínas Co-Represoras/metabolismo , Ácido Glutámico/metabolismo , Antígeno Ki-67/metabolismo , Prolina/metabolismo , Factores de Transcripción/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Astrocitoma/patología , Neoplasias Encefálicas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del TumorRESUMEN
OBJECTIVES: The improvement in the/reaction time is important, as it is an indicator of cognitive function. Therefore, there is a need, especially for adolescents in the form of techniques or courses that can improve the reaction time. Yoga was found to cause a better improvement in the health of the individuals. The present study intended to show the effects of Bhramari pranayama (Bhr.P) on reaction time in the healthy adolescents. METHODS: Of the 730 potential subjects screened, 520 apparently healthy adolescents randomly assigned to either the Bhr.P group (n-260) or control group (n-260). Bhr.P group practiced the bhramari pranayama for 3 days in a week for 6 months. The Auditory Reaction Time (ART) and the Visual Reaction Time (VRT) were assessed before and after Bhr.P pranayama practice. RESULTS: Bhr.P group shows significant shortening of response time in both VRT (from 267.13 ± 52.65 to 249.87 ± 39.41 ms) and ART (from 237.42 ± 48.12 to 227.91 ± 34.60 ms) after 6 months of Bhr.P practice. In control group subjects, no such significant changes were found (p > 0.05). CONCLUSIONS: Shortening of RT implies an improvement in the information processing and reflexes. This beneficial effect of Bhr.P on reaction time can be used for improving cognitive function in the adolescents for their academic performances.
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BACKGROUND: This study was conducted among healthy adolescents to assess the effects of a yoga breathing practice (Bhramari pranayama, Bhr.P) towards cardiac autonomic function using heart rate variability (HRV) parameters. METHODS: Of the 730 eligible subjects screened, 520 healthy adolescents who met the inclusion and exclusion criteria were randomly assigned to either yoga breathing group (nâ¯=â¯260) or control group (nâ¯=â¯260). The yoga breathing group practiced Bhr.P. five days a week for a duration of six months while the control group continued with their daily routine without any intervention. Outcome measures were time and frequency domain of HRV in both groups which were assessed before and after the intervention using Lead II ECG. Linear models were used in the analysis of short term HRV. RESULTS: After 6 months of yoga breathing, the time domain parameters of short term HRV showed significant (Pâ¯<â¯0.05) improvement towards the parasympathetic domain. Frequency domain parameters also showed the same direction of changes. In contrast, control group subjects showed a trend towards a sympathetic domain. CONCLUSION: The present study showed a positive shift in cardiac autonomic modulation towards parasympathetic predominance after 6 months of yoga breathing practice among apparently healthy adolescents.
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Pranayama, a branch of yoga practice is extremely beneficial to mankind in maintaining sound physical and mental health and this article aims to attain an insight on the studies conducted on the effectiveness of Bhramari Pranayama (Bhr.P) on health. The studies done until May 2016 were found using Medline, Embase, Google scholar and manual search. Studies conducted on the health effectiveness of Bhr.P specifically were included on the basis of prisma guidelines. The data were defined by their objectives, methodology, study setting, findings, interventions done and implications suggested in the study. Methodological Quality Rating Scale (MQRS) and Newcastle-Ottawa Scale (NOS) were used in reviewing and reporting results of the included studies. 6 studies satisfied the inclusion criteria; 2 studies were done on the cold pressor test, one on heart rate and BP, one on EEG changes, one each on the inhibitory response and tinnitus condition. In the included studies, the Bhr.P practices have shown para-sympathetic dominance. There are some encouraging effects of Bhr.P on various physiological systems. Methodological quality of the included studies was evaluated to be very low and none of them were RCTs. Yet the available studies are heterogeneous, dealing in different grounds and this heterogeneity serves as a resource for the limited scope of studies on Bhr.P. Therefore, further large-scale, properly designed, randomized trials of Bhr.P on various systems have to be done to justify these effects efficiently.
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INTRODUCTION: In yoga, Pranayama has a very important role in maintaining sound health. There is some strong scientific basis on constant physiological changes produced when pranayama is practiced for long duration. Still, there exists a dearth of literature on the effect of Bhramari pranayama (Bhr.p) on physiological systems. AIM: To assess the immediate effect of Bhramari pranayama (Bhr.P) practice on the resting cardiovascular parameters in healthy adolescents. MATERIALS AND METHODS: Sixty apparently healthy adolescents of both sex participated in the study. They were randomly divided into Bhr.P (n-30) and control (n-30) group. Informed consent was obtained after explaining the detailed procedure of the study. Bhr.P group practiced Bhramari pranayama for 45 min (5 cycles) and control group was allowed to do normal breathing (12-16 breath /min). Heart rate (HR) was assessed by radial artery palpation method and blood pressure was recorded in supine position after 5 minutes of rest by sphygmomanometer. RESULTS: The HR reduced significantly (p-0.001) in Bhr.P group. BP indices, Pulse Pressure (PP), Mean Arterial Pressure (MAP), Rate Pressure Product (RPP) and Double Product (DoP) significantly decreased after Bhr.p practice compared with control. Pre and Post inter group analysis also showed that significant reduction in HR and BP indices in Bhr.P group. CONCLUSION: Present study showed that Bhr.P practice produces relaxed state and in this state parasympathetic activity overrides the sympathetic activity. It suggests that Bhramari pranayama improves the resting cardiovascular parameters in healthy adolescents.
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BACKGROUND: Further quest for new anti-fungal compounds with proven mechanisms of action arises due to resistance and dose limiting toxicity of existing agents. Among the human fungal pathogens C. albicans predominate by infecting several sites in the body and in particular oral cavity and root canals of human tooth. METHODS: In the present study, we screened a library of ß-lactam substituted polycyclic fused pyrrolidine/pyrrolizidine compounds against Candida sp. Detailed molecular studies were carried out with the active compound 3 on C. albicans. Morphological damage and antibiofilm activity of compound 3 on C. albicans was studied using scanning electron microscopy (SEM). Biochemical evidence for membrane damage was studied using flow cytometry. In silico docking studies were carried out to elucidate the mechanism of action of compound 3. Further, the antifungal activity of compound 3 was evaluated in an ex vivo dentinal tubule infection model. RESULTS: Screening data showed that several new compounds were active against Candida sp. Among them, Compound 3 was most potent and exerted time kill effect at 4h, post antifungal effect up to 6h. When used in combination with fluconazole or nystatin, compound 3 revealed an minimum inhibitory concentration (MIC) decrease by 4 fold for both drugs used. In-depth molecular studies with compound 3 on C. albicans showed that this compound inhibited yeast to hyphae (Y-H) conversion and this involved the cAMP pathway. Further, SEM images of C. albicans showed that compound 3 caused membrane damage and inhibited biofilm formation. Biochemical evidence for membrane damage was confirmed by increased propidium iodide (PI) uptake in flow cytometry. Further, in silico studies revealed that compound 3 docks with the active site of the key enzyme 14-α-demethylase and this might inhibit ergosterol synthesis. In support of this, ergosterol levels were found to be decreased by 32 fold in compound 3 treated samples as analyzed by high performance liquid chromatography (HPLC). Further, the antifungal activity of compound 3 was evaluated in an ex vivo dentinal tubule infection model, which mimics human tooth root canal infection. Confocal laser scanning microscopy studies showed 83% eradication of C. albicans and a 6 log reduction in colony forming unit (CFU) after 24h treatment in the infected tooth samples in this model. CONCLUSION: Compound 3 was found to be very effective in eradicating C. albicans by inhibiting cAMP pathway and ergosterol biosynthesis. GENERAL SIGNIFICANCE: The results of this study can pave the way for developing new antifungal agents with well deciphered mechanisms of action and can be a promising antifungal agent or medicament against root canal infection.
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Inhibidores de 14 alfa Desmetilasa/farmacología , Antifúngicos , Candida albicans/crecimiento & desarrollo , Candidiasis/tratamiento farmacológico , AMP Cíclico/metabolismo , Cavidad Pulpar/microbiología , Modelos Biológicos , Sistemas de Mensajero Secundario , Esterol 14-Desmetilasa/metabolismo , beta-Lactamas , Antifúngicos/química , Antifúngicos/farmacología , Candida albicans/ultraestructura , Candidiasis/metabolismo , Candidiasis/patología , Cavidad Pulpar/metabolismo , Cavidad Pulpar/ultraestructura , Humanos , beta-Lactamas/química , beta-Lactamas/farmacologíaRESUMEN
The antibacterial activity of ß-lactam derived polycyclic fused pyrrolidine/pyrrolizidine derivatives synthesized by 1, 3-dipolar cycloaddition reaction was evaluated against microbes involved in dental infection. Fifteen compounds were screened; among them compound 3 showed efficient antibacterial activity in an ex vivo dentinal tubule model and in vivo mice infectious model. In silico docking studies showed greater affinity to penicillin binding protein. Cell damage was observed under Scanning Electron Microscopy (SEM) which was further proved by Confocal Laser Scanning Microscope (CLSM) and quantified using Flow Cytometry by PI up-take. Compound 3 treated E. faecalis showed ROS generation and loss of membrane integrity was quantified by flow cytometry. Compound 3 was also found to be active against resistant E. faecalis strains isolated from failed root canal treatment cases. Further, compound 3 was found to be hemocompatible, not cytotoxic to normal mammalian NIH 3T3 cells and non mutagenic. It was concluded that ß-lactam compound 3 exhibited promising antibacterial activity against E. faecalis involved in root canal infections and the mechanism of action was deciphered. The results of this research can be further implicated in the development of potent antibacterial medicaments with applications in dentistry.