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Ablative composites serve as sacrificial materials, protecting underlying materials from high-temperature environments by endothermic reactions. These materials undergo various phenomena, including thermal degradation, pyrolysis, gas generation, char formation, erosion, gas flow, and different modes of heat transfer (such as conduction, convection, and radiation), all stemming from these endothermic reactions. These phenomena synergize to form a protective layer over the underlying materials. Carbon, with its superb mechanical properties and various available forms, is highlighted, alongside phenolics known for good adhesion and fabric ability and elastomers valued for flexibility and resilience. This study focuses on recent advancements in carbon-and-phenolic and carbon-and-elastomeric composites, considering factors such as erosion speed; high-temperature resistance; tensile, bending, and compressive strength; fiber-matrix interaction; and char formation. Various authors' calculations regarding the percentage reduction in linear ablation rate (LAR) and mass ablation rate (MAR) are discussed. These analyses inform potential advancements in the field of carbon/phenolic and carbon/elastomeric ablative composites.
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INTRODUCTION: Melanoma is a rare but highly malignant form of skin cancer. Although recent targeted and immune-based therapies have improved survival rates by 10-15%, effective melanoma treatment remains challenging. Therefore, novel, combinatorial therapy options such as non-thermal atmospheric pressure plasma (NTP) are being investigated to inhibit and prevent chemoresistance. Although several studies have reported the apoptotic and inhibitory effects of reactive oxygen species produced by NTP in the context of melanoma, the intricate molecular network that determines the role of microRNAs (miRNAs) in regulating NTP-mediated cell death remains unexplored. OBJECTIVES: This study aimed to explore the molecular mechanisms and miRNA networks regulated by NTP-induced oxidative stress in melanoma cells. METHODS: Melanoma cells were exposed to NTP and then subjected to high-throughput miRNA sequencing to identify NTP-regulated miRNAs. Various biological processes and underlying molecular mechanisms were assessed using Alamar Blue, propidium iodide (PI) uptake, cell migration, and clonogenic assays followed by qRT-PCR and flow cytometry. RESULTS: NTP exposure for 3 min was sufficient to modulate the expression of several miRNAs, inhibiting cell growth. Persistent NTP exposure for 5 min increased differential miRNA regulation, PI uptake, and the expression of genes involved in cell cycle arrest and death. qPCR confirmed that miR-200b-3p and miR-215-5p upregulation contributed to decreased cell viability and migration. Mechanistically, inhibiting miR-200b-3p and miR-215-5p in SK-2 cells enhancedZEB1, PI3K, and AKT expression, increasing cell proliferation and viability. CONCLUSION: This study demonstrated that NTP exposure for 5 min results in the differential regulation of miRNAs related to the PI3K-AKT-ZEB1 axis and cell cycle dysregulation to facilitate melanoma suppression.
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Colorectal small cell carcinomas are very rare neuroendocrine malignancies of the colon or rectum. They have poor prognosis due to the aggressive and highly recurrent nature of the disease. It is a malignancy that is also poorly understood with limited literature, and thus there is no consensus in management. This case report presents the clinical features and radiological images of an otherwise healthy 74-year-old gentleman with a rare and aggressive 112-mm rectosigmoid small cell carcinoma with evidence of metastatic disease. This report will also discuss the most current and pertinent diagnostic and therapeutic recommendations from the literature.
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While rare, serious adverse effects including euglycemic diabetic ketoacidosis (EDKA) have been associated with sodium-glucose cotransporter-2 inhibitor (SGLT2i) use. We present an interesting case of SGLT2i-induced EDKA occurring two years after initiation of therapy. Most patients with EDKA recover with prompt recognition and treatment. Patient education about identifying early signs remains a cornerstone of early identification and response to SGLT2i-induced EDKA.
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BACKGROUND: The healthcare infrastructure of a country determines the health-seeking behaviour of the population. In developing countries such as India, there is a great disparity in the distribution of healthcare institutions across urban and rural areas with disadvantages for people living in rural areas. OBJECTIVES: Our objectives were to study the health-seeking behavior and factors associated with the use of formal healthcare among the Gorakhpur Health and Demographic Surveillance System (GHDSS) cohort of North India. METHODS: The study was conducted in 28 villages from two rural blocks in the Gorakhpur district of eastern Uttar Pradesh, North India. Structured questionnaires were used to collect the data with regard to demographics, health-seeking behaviour and healthcare utilization. An adjusted odds ratio with 95% confidence interval was used to report the factors associated with the utilization of healthcare. RESULTS: Out of 120,306 individuals surveyed, 19,240 (16%) individuals reported having any health problem in the last 15 days. Of them, 90% sought healthcare for their health needs. The formal healthcare utilization was 79%. The use of public health facilities was very low (37%) with most of the people seeking treatment from private healthcare (63%). Females, people with a higher level of education (graduate and above), and those belonging to rich and middle tercile were more likely to use formal healthcare services. Among different ailments, respiratory problems, gastrointestinal problems, and musculoskeletal problems were associated with decreased use of formal healthcare. CONCLUSION: About four in five individuals surveyed who had health problems sought treatments from formal healthcare with three in five preferring private institutions to public healthcare facilities due to a perceived higher level of treatment quality and nearby availability. There is an urgent need to re-establish community trust among public healthcare facilities with a focus on delivering on-site health care and enhancing the quality of services offered by public healthcare institutions.
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Dropped gallstones are a known complication of laparoscopic cholecystectomy. Rarely, dropped stones may be embedded within the potential intraperitoneal spaces or abdominal wall, mimicking metastatic implants, tuberculosis, peritoneal loose body, actinomyces, and primary tumors, which when coupled with the fact that most bile stones are radiolucent, leads to diagnostic challenges. Here, we report a case of abdominal wall abscess due to a dropped stone that presented over 15 years after laparoscopic cholecystectomy. An 86-year-old male with laparoscopic cholecystectomy for management of acute cholecystitis complicated by post-cholecystectomy choledocholithiasis over 15 years back presented to the emergency department with intermittent, asymmetric abdominal "bulging" and a reported 16-pound weight loss of 3 months duration. He remained hemodynamically stable and physical examination demonstrated approximately 9 cm × 7 cm, nontender and slightly fluctuant mass appreciable on the right lateral abdominal wall extending to the right flank. Laboratory revealed leukocytosis and elevated lactic acid. Abdominal ultrasound and abdominal computed tomography demonstrated a 10.6 × 7 × 16 cm cystic mass with echogenic debris adjacent to the anterior segment of the right hepatic lobe. The patient presented multiple times with re-accumulation. A drain was subsequently placed and antibiotic therapy initiated with subsequent resolution. Follow-up magnetic resonance imaging revealed a punctate calcification within the abscess pocket. Retained stones should be considered in the differentials of patients presenting with abdominal discomfort and abdominal "masses." The clinical suspicion must remain high secondary to the potential temporally prolonged presentation, indolent nature of inflammation, and unusual sites of physical manifestations.
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Background: Noncommunicable disease (NCD) multimorbidity throws a unique challenge to healthcare systems globally in terms of not only management of disease, but also familial, social, and economic implications associated with it. Objective: To assess the prevalence of NCD multimorbidity and its associated risk factors along with health expenditures among adults (≥18 years) living in a rural area. Methods: A secondary data analysis of the first-round survey done as part of the Gorakhpur Health and Demographic Surveillance Site (GHDSS) was done. Information related to self-reported morbidity and other variables related to sociodemographics and out-of-pocket expenditure (OOPE) was captured using a pretested questionnaire. Multivariable cluster adjusted binomial regression analysis was done to identify factors associated with multimorbidity. Results: The overall prevalence of NCD multimorbidity was found to be 1.8% (95% CI: 1.7-1.9%). The prevalence of NCD multimorbidity was highest among elderly (≥60 years) [6.0% (95% CI: 5.5-6.5%)] and among women [2.4% (95% CI: 2.3-2.6%)]. Sociodemographic factors, such as age, gender, occupation, education, marital status, religion, caste, and household wealth, were all found to be independently associated with NCD multimorbidity. The median annual OOPE was found to be significantly higher among those with NCD multimorbidity (INR 20,000) compared with those with no NCD (INR 5,000) or having only one NCD (INR 8,000). Conclusion: Among the adults in GHDSS, about 13 in every 100 were suffering from at least one NCD and around two in 100 were having NCD multimorbidity. Those with NCD multimorbidity spent almost four times higher annual OOPE compared with those without NCDs.
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Multimorbidade , Doenças não Transmissíveis , Adulto , Idoso , Estudos Transversais , Feminino , Gastos em Saúde , Humanos , Masculino , Doenças não Transmissíveis/epidemiologia , PrevalênciaRESUMO
Carcinogenesis is a major concern that severely affects the human population. Owing to persistent demand for novel therapies to treat and prohibit this lethal disease, research interest among scientists is drawing its huge focus toward natural products, as they have minimum toxicity comparable with existing treatment methods. The plants produce secondary metabolites, which are known to have the anticancer potential for clinical drug development. Furthermore, the use of nanocarriers could boost the solubility and stability of phytocompounds to obtain site-targeting delivery. The identification of potential phytochemicals in natural compounds would be beneficial for the synthesis of biocompatible nanoemulsions. The present study aimed to investigate the potential cytotoxicity of ethanol extracts of Hibiscus syriacus and Cinnamomum loureirii Nees plant parts on human skin melanoma (G361) and lung adenocarcinoma (A549) cells. Importantly, biochemical analysis results showed the presence of high phenol (50-55 µgGAE/mg) and flavonoids [42-45 µg quercetin equivalents (QE)/mg] contents with good antioxidant activity (40-58%) in C. loureirii Nees plants extracts. This plant possesses potent antiproliferative activity (60-90%) on the malignant G361 and A549 and cell lines correlated with the production of nitric oxide. Especially, C. loureirii plant extracts have major metabolites that exhibit cancer cell death associated with cell cycle arrest. These findings support the potential application of Cinnamomum for the development of therapeutic nanoemulsion in future cancer therapy.
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In the field of tissue engineering, there are several issues to consider when designing biomaterials for implants, including cellular interaction, good biocompatibility, and biochemical activity. Biomimetic mineralization has gained considerable attention as an emerging approach for the synthesis of biocompatible materials with complex shapes, categorized organization, controlled shape, and size in aqueous environments. Understanding biomineralization strategies could enhance opportunities for novel biomimetic mineralization approaches. In this regard, mussel-inspired biomaterials have recently attracted many researchers due to appealing features, such as strong adhesive properties on moist surfaces, improved cell adhesion, and immobilization of bioactive molecules via catechol chemistry. This molecular designed approach has been a key point in combining new functionalities into accessible biomaterials for biomedical applications. Polydopamine (PDA) has emerged as a promising material for biomaterial functionalization, considering its simple molecular structure, independence of target materials, cell interactions for adhesion, and robust reactivity for resulting functionalization. In this review, we highlight the strategies for using PDA to induce the biomineralization of hydroxyapatite (HA) on the surface of various implant materials with good mechanical strength and corrosion resistance. We also discuss the interactions between the PDA-HA coating, and several cell types that are intricate in many biomedical applications, involving bone defect repair, bone regeneration, cell attachment, and antibacterial activity.
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Biomineralização/efeitos dos fármacos , Indóis/farmacologia , Polímeros/farmacologia , Engenharia Tecidual/métodos , Animais , Biomimética/métodos , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Adesão Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Durapatita/metabolismo , Humanos , Indóis/metabolismo , Osteogênese/efeitos dos fármacos , Polímeros/metabolismo , Engenharia Tecidual/tendênciasRESUMO
BACKGROUND: Lateralising calcaneal osteotomy for pes cavus is generally regarded to be harder to shift than a medialising calcaneal osteotomy for pes planus. The aim of our study was to determine the structures which restrain a lateral shift. METHODS: Lateralising calcaneal osteotomy was performed on four soft-embalmed cadavers via a standard lateral approach and the lateral calcaneal shift was measured before and after the release of flexor retinaculum. Further exploratory dissection around the osteotomy site revealed the abductor hallucis muscle to be the main restraint to the lateral shift of the calcaneus. Subsequently, lateralising calcaneal osteotomy was performed on another four cadavers and the abductor hallucis muscle fascia as well as the plantar fascia was released. The lateral shift was measured before and after the fascia release, and compared with the results achieved following the flexor retinaculum release in the first four cadavers. RESULTS: Lateralising calcaneal osteotomy alone resulted in an average of 4.5-mm lateral shift in the first four cadaveric specimens. Releasing the flexor retinaculum led to a further 3-mm increase of lateral shift on average. In the next four cadaveric specimens, lateralising calcaneal osteotomy alone resulted in an average of 5.5-mm lateral shift. Release of abductor hallucis muscle fascia and the plantar fascia in these four specimens increased the lateral shift by an additional 7 mm on average. Hence, release of abductor hallucis muscle fascia resulted in an extra 4-mm shift on average compared with what is achieved with flexor retinaculum release. CONCLUSIONS: Abductor hallucis muscle fascia was discovered to be one of the main structures limiting the lateral shift in lateralising calcaneal osteotomy. Release of fascia over this muscle as well as the plantar fascia should help in improving lateral shift. Further experimental and clinical research is necessary to confirm the findings of this pilot study.
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Neurilemoma , Cistos Ovarianos , Neoplasias Retroperitoneais , Feminino , Humanos , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Cistos Ovarianos/diagnóstico por imagem , Cistos Ovarianos/cirurgia , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/cirurgia , Espaço RetroperitonealRESUMO
Breast cancer is a widely distributed type of cancer in women worldwide, and tumor relapse is the major cause of breast cancer death. In breast cancers, the acquisition of metastatic ability, which is responsible for tumor relapse and poor clinical outcomes, has been linked to the acquisition of the epithelial-mesenchymal transition (EMT) program and self-renewal traits (CSCs) via various signaling pathways. These phenomena confer resistance during current therapies, thus creating a major hurdle in radiotherapy/chemotherapy. The role of very low doses of radiation (LDR) in the context of EMT has not yet to be thoroughly explored. Here, we report that a 0.1 Gy radiation dose reduces cancer progression by deactivating the JAK1/STAT3 pathway. Furthermore, LDR exposure also reduces sphere formation and inhibits the self-renewal ability of breast cancer cells, resulting in an attenuated CD44+/CD24- population. Additionally, in vivo findings support our data, providing evidence that LDR is a promising option for future treatment strategies to prevent cancer metastasis in breast cancer cases.
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Neoplasias da Mama/radioterapia , Transição Epitelial-Mesenquimal/efeitos da radiação , Raios gama/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Janus Quinase 1/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos da radiação , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Relação Dose-Resposta à Radiação , Feminino , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/metabolismo , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Plasmídeos/química , Plasmídeos/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/genética , Transfecção , Carga Tumoral/efeitos da radiação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
INTRODUCTION: Patellar tendon rupture can occur due to multiple causes ranging from inflammatory pathologies to episodes of trauma. Extensor mechanism rupture is a rare complication of total knee arthroplasty (TKA). In most of these cases, the failure occurs as avulsion of patellar tendon from tibial tuberosity. We report a rare case with bilateral mid-substance patellar tendon rupture one month after bilateral total knee arthroplasty. CASE PRESENTATION: A 69-year-old male was operated for bilateral grade 4 osteoarthritis. On day 30 post-operative, he sustained bilateral patellar tendon rupture while getting up from toilet. He had a history of multiple steroid injections in the knee, which could have affected the tendon. The other etiologies could be inherent weakness of tendon due to diabetes and old age and micro-trauma/stretch associated with sudden correction of previous deformity by TKA. The management in our case was done by primary repair along with augmentation by autologous semitendinosus graft and suture anchor. CONCLUSION: The operating surgeon must be aware of the possibility of patellar tendon rupture following total knee arthroplasty. This will help the surgeon in early recognition and preparedness to handle such complications, should they arise. Surgeons may consider advising caution to both patient and rehabilitation team in cases with old age, chronic diabetes mellitus, and with a history of steroid injections.
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BACKGROUND: With the advent of MRI (Magnetic Resonance Imaging), Synovial lesions around knee are being more and more easily detected. Synovial lesions of knee present with boggy swelling, effusion, pain, and restriction of motion. Differential diagnoses of such lesions include pigmented villonodular synovitis, synovial lipoma, synovial chondromatosis, rheumatoid arthritis, synovial hemangioma, amyloid arthropathy, xanthomata and lipoma arborescens. CT and MRI often help in diagnosis of such lesions. MRI of Lipoma Arborescens has been regarded to have characteristic diagnostic appearance - it includes a synovial mass with frond-like architecture and fat signal intensity on all pulse sequences. Sometimes Lipoma Arborescens can present in conjunction with inflammatory arthritis. Synovectomy is often curative for such conditions. FINDINGS: We report two cases where lesions diagnosed as Lipoma Arborescens on MRI subsequently revealed to be chronic inflammatory synovitis, characterized by absence of fat infiltration in histopathological examination - refuting the original diagnosis. There was infiltration of lymphocytes and neutrophils in the synovium, suggestive of chronic inflammatory arthritis. Both of these patients required management from rheumatologist, and had relief of symptoms after use of methotrexate and hydroxychloroquine. We also report a third case, where a loose body appearing as chondral fragment on arthroscopy was subsequently diagnosed as an organized hematoma on histopathological examination. CONCLUSION: Diagnostic pitfalls after MRI of the knee is not uncommon. For example - normal variant of meniscomeniscal ligaments have been reported as meniscal tears; motion artifacts have been falsely reported as meniscal injuries; and meniscofemoral ligament can appear as free osteochondral fragment. In most of these cases, a routine arthroscopy is enough to clear the confusion. However, as evident in the three cases described here - in some synovial lesions of knee joint, even after MRI and arthroscopic examination, histopathological confirmation may still be prudent. In spite of availability of advanced imaging technologies and high definition arthroscopy equipment, an arthroscopy surgeon still must not forget the value of histopathological examination in establishing the true nature of synovial lesions of the knee joint.
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INTRODUCTION: External fixator application can be difficult for olecranon fractures in presence of large degloving injuries. We describe use of simple Ilizarov ring fixator construct for grade IIIB open olecranon fracture management. CASE REPORT: A 45-year-old female with Grade III B open comminuted olecranon fracture (30*15cm degloving area) and ulnar nerve palsy was treated with a novel ring fixator construct. Two cut-end olive wires were passed from the proximal olecranon across the fracture site in intramedullary fashion exiting dorsally at mid-ulnar level through healthy skin and were attached to an Ilizarov half ring secured by perpendicular wires. The olive wires were tensioned, achieving compression and stability. Range of motion (ROM) exercises could be started quickly as the elbow was not spanned. Wound healed after skin grafting and at one-year follow-up the patient has good functional results (PRE 7, DASH 9.48), elbow ROM 10°-130°, 75° pronation and 85° supination. The patient returned to pre-injury occupational activities and had no pain. At three-year follow-up, the x-ray and CT showed union of olecranon fragment with well-maintained congruency. CONCLUSION: Internal fixation in most cases may be precluded by the soft tissue trauma and risk of infection. In addition, the small proximal fragment precludes a stable external fixation. In this technique, the hardware is kept away from the open wound allowing better wound inspection and care. The intramedullary olive wires provide compression and stability, and thus allow early ROM. Ilizarov half-ring and olive wire fixation can be an useful option for management of high grade open olecranon fractures because of its advantages, viz. stable fixation, minimal internal hardware, optimal wound care, immediate initiation of range of motion, and good outcome.
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Two new tetracationic hetero-bimetallacycles, compounds 4 and 5, have been constructed from an N,N'-bis(4-(pyridin-4-ylethynyl)phenyl)pyridine-2,6-dicarboxamide ligand (1), and cis-blocked complexes [M(dppf)(OTf)2 ] (dppf=1,1'-bis(diphenylphosphino)ferrocene; OTf=trifluoromethanesulfonate; M=Pd (2), Pt (3)) in CH3 NO2 /CH2 Cl2 (1:1) solvent. Both complexes were isolated with adequate yields as triflate salts and were then characterized using (1) H, (13) C, and (31) Pâ NMR spectroscopy, elemental analysis, UV/Vis spectroscopy, and high-resolution electrospray mass spectrometry (HR-ESMS). The molecular structure of 4 was determined by molecular mechanics force-field calculations. The cytotoxic effect of both new complexes were analyzed against T98G (brain tumor), KB (head and neck cancer), SNU-80 (thyroid cancer), and HEK-293 non-malignant cell lines. The cytotoxicity of complexes 4 and 5 were found to be considerably more effective against cancer cells than reference drug cisplatin. Annexin-V/PI staining, caspase-3/7 activity, and the reduction in mitochondrial membrane potential justify a significant level of apoptosis in complex-treated cells.