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1.
Cell Commun Signal ; 22(1): 324, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867255

RESUMO

BACKGROUND: KRAS-mutant non-small cell lung cancer (NSCLC) shows a relatively low response rate to chemotherapy, immunotherapy and KRAS-G12C selective inhibitors, leading to short median progression-free survival, and overall survival. The MET receptor tyrosine kinase (c-MET), the cognate receptor of hepatocyte growth factor (HGF), was reported to be overexpressed in KRAS-mutant lung cancer cells leading to tumor-growth in anchorage-independent conditions. METHODS: Cell viability assay and synergy analysis were carried out in native, sotorasib and trametinib-resistant KRAS-mutant NSCLC cell lines. Colony formation assays and Western blot analysis were also performed. RNA isolation from tumors of KRAS-mutant NSCLC patients was performed and KRAS and MET mRNA expression was determined by real-time RT-qPCR. In vivo studies were conducted in NSCLC (NCI-H358) cell-derived tumor xenograft model. RESULTS: Our research has shown promising activity of omeprazole, a V-ATPase-driven proton pump inhibitor with potential anti-cancer properties, in combination with the MET inhibitor tepotinib in KRAS-mutant G12C and non-G12C NSCLC cell lines, as well as in G12C inhibitor (AMG510, sotorasib) and MEK inhibitor (trametinib)-resistant cell lines. Moreover, in a xenograft mouse model, combination of omeprazole plus tepotinib caused tumor growth regression. We observed that the combination of these two drugs downregulates phosphorylation of the glycolytic enzyme enolase 1 (ENO1) and the low-density lipoprotein receptor-related protein (LRP) 5/6 in the H358 KRAS G12C cell line, but not in the H358 sotorasib resistant, indicating that the effect of the combination could be independent of ENO1. In addition, we examined the probability of recurrence-free survival and overall survival in 40 early lung adenocarcinoma patients with KRAS G12C mutation stratified by KRAS and MET mRNA levels. Significant differences were observed in recurrence-free survival according to high levels of KRAS mRNA expression. Hazard ratio (HR) of recurrence-free survival was 7.291 (p = 0.014) for high levels of KRAS mRNA expression and 3.742 (p = 0.052) for high MET mRNA expression. CONCLUSIONS: We posit that the combination of the V-ATPase inhibitor omeprazole plus tepotinib warrants further assessment in KRAS-mutant G12C and non G12C cell lines, including those resistant to the covalent KRAS G12C inhibitors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Mutação , Omeprazol , Proteínas Proto-Oncogênicas c-met , Proteínas Proto-Oncogênicas p21(ras) , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Linhagem Celular Tumoral , Animais , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Omeprazol/farmacologia , Omeprazol/uso terapêutico , Camundongos , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , Pirimidinonas/farmacologia , Pirimidinonas/uso terapêutico , Feminino , Triazinas/farmacologia , Triazinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Piperazinas , Piperidinas , Piridazinas , Piridonas
2.
J Orthop ; 45: 87-90, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37869414

RESUMO

Introduction: Osteoarthritis of the knee is a common problem in the elderly, leading to severe morbidity. Total Knee Arthroplasty (TKA) is a widely validated surgery to provide a remarkable extent of knee function and simultaneously alleviates pain for knee osteoarthritis (OA). It is clearly understood that precision of the rotational alignment and accuracy of the technique in the placement of the femoral component is a prerequisite for excellent and successful outcomes of TKA. Advanced technology has now allowed surgeons to understand patient-specific variabilities in anatomical reference landmarks and the relationship of component positioning in relation to the reference landmarks to achieve accurate gap balancing with minimal soft tissue release.14 Robotic Arm Assisted-Total Knee Arthroplasty (RAA-TKA) is a semi-automated system that enables us in replicating the same. Using this technology, the bony resections, component positions, probable component sizing and gap balancing can be tentatively planned preoperatively with CT Scan Analysis and executed intraoperatively. Hence this study was undertaken to estimate the relationship between femoral component placement to normal rotational landmarks such as the Posterior Condylar Axis (PCA) and to quantitatively evaluate coronal and sagittal plane correction obtained. Also, we aimed to use the data to detect any anatomical variations in the study population and evaluate the accuracy of predicted component sizing, including gender-based evaluation. Materials and methods: A Prospective Observational Study of 1073 knees of patients of either sex above 50 years of age with Kellgren Lawrence Grade 4 Osteoarthritis of the knee which were confirmed with X-Ray undergoing RAA-TKA using MAKO Robotic System using Stryker Triathlon (Cruciate Substituting) CS Knee was conducted during the period between 2022 and 2023 in two South Indian hospitals specializing in joint replacement surgeries. Results: We found a statistically significant difference between the native Posterior Condylar Axis (PCA) (4.82 ± 2.15°) and final femoral component external rotation (3.24 ± 1.29°) with a p-value of <0.001 at 95% confidence interval. The accuracy of component size prediction was 99.8%. Also, analysis in our study has shown the most common implant sizes to be 4 in males and 2 in females. We also found no statistically significant difference based on age, size, laterality, or primary varus deformity. Conclusions: RAA-TKA provides patient-specific alignment/restricted kinematic alignment which might further enhance the outcome for the patient. Reliable deformity correction in coronal and sagittal planes can be achieved. Accurate flexion and extension gap balancing can be done through component placement and with minimal soft tissue dissection. Irrespective of all the advantages noted in RAA-TKA, further follow-up and long-term outcome studies are required to properly gauge and analyze this new technology.

3.
Indian Pediatr ; 60(9): 703-704, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37705264
5.
Sci Adv ; 9(32): eadi1870, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37556541

RESUMO

Multicellular biological systems, particularly living neural networks, exhibit highly complex organization properties that pose difficulties for building cell-specific biocompatible interfaces. We previously developed an approach to genetically program cells to assemble structures that modify electrical properties of neurons in situ, opening up the possibility of building minimally invasive cell-specific structures and interfaces. However, the efficiency and biocompatibility of this approach were challenged by limited membrane targeting of the constructed materials. Here, we design a method for highly localized expression of enzymes targeted to the plasma membrane of primary neurons, with minimal intracellular retention. Next, we show that polymers synthesized in situ by this approach form dense extracellular clusters selectively on the targeted cell membrane and that neurons remain viable after polymerization. Last, we show generalizability of this method across a range of design strategies. This platform can be readily extended to incorporate a broad diversity of materials onto specific cell membranes within tissues and may further enable next-generation biological interfaces.


Assuntos
Neurônios , Polímeros , Polímeros/química , Neurônios/fisiologia , Membrana Celular/metabolismo , Materiais Biocompatíveis/química
6.
J Food Sci Technol ; 60(6): 1666-1673, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37187991

RESUMO

Food and nutrients play a pivotal role in the development of dentition and oral health. While diet includes the overall forms of consumed foods, the nutrients include specific micro- (vitamins and minerals) and macro- (carbohydrates, proteins, and lipids) nutrients. As much as the assimilation of macro and micronutrients depends on proper oral health for ingesting food, oral health, in turn, depends on the availability of nutrients in the food so ingested. Age, certain medical conditions, socioeconomic status, and overall changes in the evolution of society determine the type of diet which in turn influences oral health. This article has touched upon certain salient aspects of these nutrients and their bearing on overall oral health and development.

10.
Plant J ; 107(5): 1403-1419, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34165841

RESUMO

Triterpenes (30-carbon isoprene compounds) represent a large and highly diverse class of natural products that play various physiological functions in plants. The triterpene biosynthetic enzymes, particularly those catalyzing the late-stage regio-selective modifications are not well characterized. The bark of select Boswellia trees, e.g., B. serrata exudes specialized oleo-gum resin in response to wounding, which is enriched with boswellic acids (BAs), a unique class of C3α-epimeric pentacyclic triterpenes with medicinal properties. The bark possesses a network of resin secretory structures comprised of vertical and horizontal resin canals, and amount of BAs in bark increases considerably in response to wounding. To investigate BA biosynthetic enzymes, we conducted tissue-specific transcriptome profiling and identified a wound-responsive BAHD acetyltransferase (BsAT1) of B. serrata catalyzing the late-stage C3α-O-acetylation reactions in the BA biosynthetic pathway. BsAT1 catalyzed C3α-O-acetylation of αBA, ßBA, and 11-keto-ßBA in vitro and in planta assays to produce all the major C3α-O-acetyl-BAs (3-acetyl-αBA, 3-acetyl-ßBA, and 3-acetyl-11-keto-ßBA) found in B. serrata bark and oleo-gum resin. BsAT1 showed strict specificity for BA scaffold, whereas it did not acetylate the more common C3ß-epimeric pentacyclic triterpenes. The analysis of steady-state kinetics using various BAs revealed distinct substrate affinity and catalytic efficiency. BsAT1 transcript expression coincides with increased levels of C3α-O-acetyl-BAs in bark in response to wounding, suggesting a role of BsAT1 in wound-induced biosynthesis of C3α-O-acetyl-BAs. Overall, the results provide new insights into the biosynthesis of principal chemical constituents of Boswellia oleo-gum resin.


Assuntos
Acetiltransferases/metabolismo , Boswellia/enzimologia , Resinas Vegetais/metabolismo , Transcriptoma , Triterpenos/metabolismo , Acetiltransferases/genética , Vias Biossintéticas , Boswellia/anatomia & histologia , Boswellia/química , Boswellia/genética , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Genes Reporter , Especificidade de Órgãos , Casca de Planta/anatomia & histologia , Casca de Planta/química , Casca de Planta/enzimologia , Casca de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Medicinais , Resinas Vegetais/química , Nicotiana/genética , Nicotiana/metabolismo , Triterpenos/química
11.
J Korean Assoc Oral Maxillofac Surg ; 47(3): 183-189, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34187958

RESUMO

OBJECTIVES: To assess the prevalence and recovery of inferior alveolar nerve dysfunction (IAND) in mandibular fractures. MATERIALS AND METHODS: : This was a prospective cohort study. Clinical neurosensory testing was done preoperatively and the IAND was categorized as mild, moderate or severe. Postoperatively, neurosensory testing was repeated at 1 day, 1 week, 1 month, 3 months and every 3 months thereafter. RESULTS: : A total of 257 patients with 420 fractures were included in the study with a mean age of 31.7 years. Body fractures (95.9%) had the highest incidence of IAND, followed by the angle fractures (90.1%) and symphysis fractures (27.6%). The condyle and coronoid fractures did not have any IAND and hence were excluded from further study. After eliminating those cases, 232 patients remained in the study with 293 fractures. The overall prevalence of IAND in fractures occurring distal to the mandibular foramen was 56.3%. The changes until 1 week were minimal. From 1 month to 6 months, there was a significant reduction in the severity of IAND. A significant number of cases (60.0%) were lost to follow-up between 6 and 9 months. At 6 months, 23.9% of cases still had some form of IAND and 95.0% of the symphysis, 59.0% of the angle and 34.8% of the body fractures with IAND had become normal. CONCLUSION: This study documents the reduction in the degree of severity of IAND in the first six months and provides the basis for future studies with longer periods of follow-up.

12.
Contemp Clin Dent ; 11(2): 195-198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110337

RESUMO

Primary malignant melanoma of oral mucosa is a rare and aggressive tumor. It is usually seen in the 5th and 6th decades of life. Its mainstay of treatment is surgery. It has a very poor prognosis, which is attributed to its late detection and distant metastasis. Dentists are often the first clinicians to come across these lesions and need to be able to identify them at the earliest for a better prognosis. In this article, we present two cases of extensive primary malignant melanoma of the oral cavity. Clinically, both the cases had a similar appearance of grayish-black pigmented nodular swelling on the buccal aspect and grayish-black discoloration on the palatal aspect. There were no significant radiological changes in both cases, indicating the superficial spread of the lesion. A positron emission tomography scan was performed in the second patient, which did not show any distant metastasis. Surgery was advised as a treatment for both the patients.

13.
Int J Radiat Biol ; 96(12): 1513-1527, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33026919

RESUMO

PURPOSE: The nature and kind of some successful mutations achieved through gamma radiation at CSIR-CIMAP, Lucknow are reviewed and described in this article. Medicinal and aromatic crops (MACs) came under the mutation-breeding program very late - perhaps during the 1980s in India. Nevertheless, successes have been glaring and unique too. The plant breeders of the Institute concerted attempts were made for the genetic restructuring of the plant-frame in Hyoscyamus niger L. (black henbane) and Cymbopogon martinii (palmarosa), enhanced alkaloid biosynthesis in henbane, weak, or lack of latex biosynthesis in Papaver somniferum L. (Opium poppy), increased productivity of seeds in Plantago ovata F. (isabgol), and new/increased formation of essential oils in Chamomila recutita [L.] Rauschert (Chamomile) and Cymbopogon winterianus (Java citronella). Several qualitative macro mutations were generated for commercial exploitation, e.g. an unbranched (Ub) and physiologically most efficient variety Aekla and high tropane alkaloid bearing variety Aela of H. niger, opium less oil-seed variety Sujata of opium poppy, a dwarf mutant and a male sterile (ms) line of palmarosa, and new compound yielding variety of chamomile and geranium. CONCLUSIONS: The ample quantitative variation was also created by reshuffling the polygenic background in both seed and vegetatively propagated MACs, and subsequently, with applying mutation breeding approach superior varieties were evolved and released after a rigorous screening in the field-evaluation or under pipeline for release. These varieties are Niharika and Mayuri of psyllium; Vallary, CIMAP Sammohak, CIM Ujjwala, and YEL (yellow) of German chamomile and Manjari and CIM Jeeva of Java citronella.


Assuntos
Produtos Agrícolas/genética , Mutação , Melhoramento Vegetal/métodos , Plantas Medicinais/genética
14.
Contemp Clin Dent ; 11(4): 367-370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33850403

RESUMO

BACKGROUND AND OBJECTIVES: Persistent pain during the removal of mandibular third molars is often due to accessory nerve supply causing inadequate local anesthesia. This study aims to assess the requirement of routine distolingual infiltration anesthesia in addition to traditional inferior alveolar, lingual, and long buccal nerve block in mandibular third molar extractions. METHODOLOGY: Sixty patients requiring mandibular third molar extraction were randomly divided into two equal groups; Group A (Classic inferior alveolar, lingual, and buccal nerve block) and Group B (with an additional 0.2 ml distolingual infiltration). During various steps of the procedure, any complaint of pain was recorded and graded on a subjective Visual Analog Scale (VAS). RESULTS: There was no significant difference between the two groups in regard to age (P = 0.666) and sex (P = 0.432). And also, no difference was found in angulation (P = 0.757), class (P = 0.417) and position (P = 1.000) of third molars. Mean VAS scores in Group B (0.153) were significantly lower (P = 0.004) than that of Group A (0.600). VAS scores during procedural steps were significantly lower in Group B during mucoperiosteal elevation (P = 0.050), bone guttering (P = 0.037), and tooth splitting (P = 0.052). CONCLUSION: Routine distolingual infiltration anesthesia, in addition to classic inferior alveolar, lingual, and long buccal nerve block, is recommended for the extraction of mandibular third molars.

15.
Ann Maxillofac Surg ; 10(2): 320-324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33708574

RESUMO

INTRODUCTION: Dry socket is one of the most common postoperative complications following the extraction of permanent teeth, which is characterized by pain and exposed bone. The usual protocol followed for its management is irrigation of the socket and packing of the socket with medicated gel or paste to provide relatively faster pain relief and allow normal wound healing. In this study, we evaluated the outcome of management of dry socket with platelet-rich fibrin (PRF) and intraalveolar alvogyl dressing, in terms of improvement in pain and socket epithelialization after the treatment. METHODOLOGY: Thirty participants with established dry socket were randomly divided into two groups: Group A and Group B. The participants in Group A were treated with alvogyl and those in Group B were treated with PRF. Clinical parameters were assessed for both groups on the 1st day of the procedure and on the 3rd and 10th-day postoperatively for the reduction in pain and wound healing. RESULTS: There was a significant decrease in pain and the number of socket wall exposure in both the groups by the 3rd postoperative day. In both the groups, the pain had completely resolved and socket fully epithelialized by the 10th postoperative day. DISCUSSION: The use of PRF in the present study yielded promising results in terms of both pain reduction and improved wound healing which was comparable to the conventional alvogyl dressing. It may be concluded that PRF is an effective modality for the management of dry socket.

17.
J Clin Orthop Trauma ; 10(3): 503-506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061577

RESUMO

Luxatio erecta is the least common form of shoulder dislocations. Bilateral luxatio erecta with concomitant greater tuberosity fracture is further rare with only couple of cases reported so far in the literature. We present an uncommon and a rare case of post epileptic seizure related bilateral luxatio erecta with greater tuberosity fracture in a young Indian male which is unique in its etiology, method of management and rarity of its type among so far reported cases.

18.
Acta Neurol Scand ; 137(5): 488-499, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29359321

RESUMO

OBJECTIVES: While the Restless legs syndrome (RLS) is usually recognized as a chronic condition, it has often been diagnosed among patients with acute neurological illnesses, in which limb discomfort is reported. This study was conducted to determine how many among these, actually have acute-onset RLS, and also to evaluate characteristics of this subgroup of patients with Guillain-Barre syndrome (GBS) and stroke developing acute-onset RLS. METHODS: Consecutive patients diagnosed with GBS and eligible stroke patients, admitted to our Neurology services over a 1-year period, were enrolled. They were evaluated for symptoms of RLS based on IRLSSG consensus criteria and the AIIMS RLS Questionnaire for Indian patients (ARQIP). RESULTS: Forty adults with GBS and 58 with stroke were included. A total of 10 of the 40 (25%) patients with GBS developed definite acute RLS, which was mostly monophasic. Seven (70%) of these had demyelinating type of GBS, a significant association with acute RLS (P = .024). Six of the 58 stroke patients (10%) developed definite acute-onset, often persistent RLS. Subcortical location showed significant association with increased risk of developing acute RLS (P < .001). All patients diagnosed with acute-onset RLS had an immediate and good response to dopamine agonists. CONCLUSION: This is the first study showing that acute-onset RLS is common, affecting nearly 25% of patients with GBS and 10% patients with acute stroke. Recognizing and treating it can majorly contribute toward symptom relief and early improvement in the quality of life for this population.


Assuntos
Síndrome de Guillain-Barré/complicações , Síndrome das Pernas Inquietas/epidemiologia , Síndrome das Pernas Inquietas/etiologia , Acidente Vascular Cerebral/complicações , Adulto , Idoso , Povo Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Nucl Med Commun ; 38(11): 1015-1018, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28885541

RESUMO

Tc-methylene diphosphonate (Tc-MDP) bone scintigraphy images have limited number of counts per pixel. A noise filtering method based on local statistics of the image produces better results than a linear filter. However, the mask size has a significant effect on image quality. In this study, we have identified the optimal mask size that yields a good smooth bone scan image. Forty four bone scan images were processed using mask sizes 3, 5, 7, 9, 11, 13, and 15 pixels. The input and processed images were reviewed in two steps. In the first step, the images were inspected and the mask sizes that produced images with significant loss of clinical details in comparison with the input image were excluded. In the second step, the image quality of the 40 sets of images (each set had input image, and its corresponding three processed images with 3, 5, and 7-pixel masks) was assessed by two nuclear medicine physicians. They selected one good smooth image from each set of images. The image quality was also assessed quantitatively with a line profile. Fisher's exact test was used to find statistically significant differences in image quality processed with 5 and 7-pixel mask at a 5% cut-off. A statistically significant difference was found between the image quality processed with 5 and 7-pixel mask at P=0.00528. The identified optimal mask size to produce a good smooth image was found to be 7 pixels. The best mask size for the John-Sen Lee filter was found to be 7×7 pixels, which yielded Tc-methylene diphosphonate bone scan images with the highest acceptable smoothness.


Assuntos
Osso e Ossos/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-Ruído , Medronato de Tecnécio Tc 99m , Humanos , Neoplasias/diagnóstico por imagem , Cintilografia
20.
Physiol Plant ; 161(4): 502-514, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28786221

RESUMO

Abiotic stresses such as salt and drought represent adverse environmental conditions that significantly damage plant growth and agricultural productivity. In this study, the mechanism of the plant growth-promoting rhizo-bacteria (PGPR)-stimulated tolerance against abiotic stresses has been explored. Results suggest that PGPR strains, Arthrobacter protophormiae (SA3) and Dietzia natronolimnaea (STR1), can facilitate salt stress tolerance in wheat crop, while Bacillus subtilis (LDR2) can provide tolerance against drought stress in wheat. These PGPR strains enhance photosynthetic efficiency under salt and drought stress conditions. Moreover, all three PGPR strains increase indole-3-acetic acid (IAA) content of wheat under salt and drought stress conditions. The SA3 and LDR2 inoculations counteracted the increase of abscisic acid (ABA) and 1-aminocyclopropane-1-carboxylate (ACC) under both salt and drought stress conditions, whereas STR1 had no significant impact on the ABA and ACC content. The impact of PGPR inoculations on these physiological parameters were further confirmed by gene expression analysis as we observed enhanced levels of the TaCTR1 gene in SA3-, STR1- and LDR2-treated wheat seedlings as compared to uninoculated drought and salt stressed plants. PGPR inoculations enhanced expression of TaDREB2 gene encoding for a transcription factor, which has been shown to be important for improving the tolerance of plants to abiotic stress conditions. Our study suggest that PGPR confer abiotic stress tolerance in wheat by enhancing IAA content, reducing ABA/ACC content, modulating expression of a regulatory component (CTR1) of ethylene signaling pathway and DREB2 transcription factor.


Assuntos
Secas , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Rhizobium/fisiologia , Triticum/metabolismo , Triticum/fisiologia , Ácido Abscísico/metabolismo , Arthrobacter/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo
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