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1.
Proc Natl Acad Sci U S A ; 120(11): e2212270120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36877833

RESUMO

Recently, social media platforms are heavily moderated to prevent the spread of online hate speech, which is usually fertile in toxic words and is directed toward an individual or a community. Owing to such heavy moderation, newer and more subtle techniques are being deployed. One of the most striking among these is fear speech. Fear speech, as the name suggests, attempts to incite fear about a target community. Although subtle, it might be highly effective, often pushing communities toward a physical conflict. Therefore, understanding their prevalence in social media is of paramount importance. This article presents a large-scale study to understand the prevalence of 400K fear speech and over 700K hate speech posts collected from Gab.com. Remarkably, users posting a large number of fear speech accrue more followers and occupy more central positions in social networks than users posting a large number of hate speech. They can also reach out to benign users more effectively than hate speech users through replies, reposts, and mentions. This connects to the fact that, unlike hate speech, fear speech has almost zero toxic content, making it look plausible. Moreover, while fear speech topics mostly portray a community as a perpetrator using a (fake) chain of argumentation, hate speech topics hurl direct multitarget insults, thus pointing to why general users could be more gullible to fear speech. Our findings transcend even to other platforms (Twitter and Facebook) and thus necessitate using sophisticated moderation policies and mass awareness to combat fear speech.


Assuntos
Mídias Sociais , Humanos , Fala , Medo , Fertilidade , Ódio
2.
Mol Cancer ; 23(1): 18, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243280

RESUMO

The production and release of tumor-derived small extracellular vesicles (TDSEVs) from cancerous cells play a pivotal role in the propagation of cancer, through genetic and biological communication with healthy cells. TDSEVs are known to orchestrate the invasion-metastasis cascade via diverse pathways. Regulation of early metastasis processes, pre-metastatic niche formation, immune system regulation, angiogenesis initiation, extracellular matrix (ECM) remodeling, immune modulation, and epithelial-mesenchymal transition (EMT) are among the pathways regulated by TDSEVs. MicroRNAs (miRs) carried within TDSEVs play a pivotal role as a double-edged sword and can either promote metastasis or inhibit cancer progression. TDSEVs can serve as excellent markers for early detection of tumors, and tumor metastases. From a therapeutic point of view, the risk of cancer metastasis may be reduced by limiting the production of TDSEVs from tumor cells. On the other hand, TDSEVs represent a promising approach for in vivo delivery of therapeutic cargo to tumor cells. The present review article discusses the recent developments and the current views of TDSEVs in the field of cancer research and clinical applications.


Assuntos
Vesículas Extracelulares , MicroRNAs , Neoplasias , Humanos , Relevância Clínica , Neoplasias/patologia , MicroRNAs/genética , Comunicação Celular , Transição Epitelial-Mesenquimal , Microambiente Tumoral , Metástase Neoplásica/patologia
3.
Phys Rev Lett ; 132(9): 096301, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489611

RESUMO

This Letter presents a nonlocal study on the electric-field-tunable edge transport in h-BN-encapsulated dual-gated Bernal-stacked (ABA) trilayer graphene across various displacement fields (D) and temperatures (T). Our measurements revealed that the nonlocal resistance (R_{NL}) surpassed the expected classical Ohmic contribution by a factor of at least 2 orders of magnitude. Through scaling analysis, we found that the nonlocal resistance scales linearly with the local resistance (R_{L}) only when the D exceeds a critical value of ∼0.2 V/nm. Additionally, we observed that the scaling exponent remains constant at unity for temperatures below the bulk-band gap energy threshold (T<25 K). Further, the value of R_{NL} decreases in a linear fashion as the channel length (L) increases. These experimental findings provide evidence for edge-mediated charge transport in ABA trilayer graphene under the influence of a finite displacement field. Furthermore, our theoretical calculations support these results by demonstrating the emergence of dispersive edge modes within the bulk-band gap energy range when a sufficient displacement field is applied.

4.
Macromol Rapid Commun ; 45(10): e2300730, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38407503

RESUMO

Chemical sensing of harmful species released either from natural or anthropogenic activities is critical to ensuring human safety and health. Over the last decade, conjugated microporous polymers (CMPs) have been proven to be potential sensor materials with the possibility of realizing sensing devices for practical applications. CMPs found to be unique among other porous materials such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) due to their high chemical/thermal stability, high surface area, microporosity, efficient host-guest interactions with the analyte, efficient exciton migration along the π-conjugated chains, and tailorable structure to target specific analytes. Several CMP-based optical, electrochemical, colorimetric, and ratiometric sensors with excellent selectivity and sensing performance were reported. This review comprehensively discusses the advances in CMP chemical sensors (powders and thin films) in the detection of nitroaromatic explosives, chemical warfare agents, anions, metal ions, biomolecules, iodine, and volatile organic compounds (VOCs), with simultaneous delineation of design strategy principles guiding the selectivity and sensitivity of CMP. Preceding this, various photophysical mechanisms responsible for chemical sensing are discussed in detail for convenience. Finally, future challenges to be addressed in the field of CMP chemical sensors are discussed.


Assuntos
Polímeros , Polímeros/química , Porosidade , Estruturas Metalorgânicas/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Pós/química , Substâncias Explosivas/análise , Substâncias Explosivas/química , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Propriedades de Superfície
5.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38189620

RESUMO

Dissociation of CO2 on copper surfaces is an important model system for understanding the elementary steps in catalytic conversion of CO2 to methanol. Using molecular beam-surface scattering methods, we measure the initial dissociation probabilities (S0) of CO2 on a flat, clean Cu(110) surface under ultrahigh vacuum conditions. The observed S0 ranges from 3.9 × 10-4 to 1.8 × 10-2 at incidence energies of 0.64-1.59 eV. By extrapolating the trend observed in the incidence energy dependence of S0, we estimate the lower limit of the dissociation barrier on terrace sites to be around 2 eV. We discuss these results in the context of what is known from previous studies on this system using different experiments and theoretical/computational methods. These findings are anticipated to be valuable for correctly understanding the elementary steps in CO2 dissociation on Cu surfaces.

6.
Pediatr Cardiol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647658

RESUMO

We recently encountered several cases of tetralogy of Fallot with an abnormally oriented S-shaped ascending aorta. In this retrospective study, we sought to clarify morphology of this unusual under-recognized variant. Databases were reviewed to identify all patients with tetralogy of Fallot having an S-shaped ascending aorta. Computed tomographic angiography was used for the assessment of cardiac morphology. Out of the 21 patients, 18 (86%) had a right aortic arch, 2 (9%) had a left aortic arch, and the remaining patient (5%) had a double aortic arch. Patients with a right aortic arch, compared to age and sex-matched patients with a right aortic arch but normally oriented ascending aorta, had lesser aortic override (29.3 ± 14% vs 54.8 ± 13.2%; p = 0.0001) and a wider ascending aorta (25.2 ± 6.9 vs 18.0 ± 3.2 mm; p = 0.0003). The S-shaped ascending aorta was located posteriorly, with a higher sterno-aortic distance (25.5 ± 7.7 vs 9.9 ± 4.5 mm; p = 0.0001). The ascending aorta among patients with tortuosity was longer (4.12 ± 1.7 vs 3.07 ± 0.82, p = 0.03) but with similar tortuosity index (1.22 ± 0.19 vs 1.15 ± 0.17, p = 0.23). Of the cases with right aortic arch and S-shaped ascending aorta, 16 (89%) had extrinsic compression of the right pulmonary artery (p = 0.0001), while 7 (39%) had crossed pulmonary arteries (p = 0.008), with no such findings among those with normally oriented ascending aorta. Tetralogy of Fallot with an S-shaped ascending aorta is a variant with lesser aortic override and a more posteriorly located ascending aorta. Compression of the right pulmonary artery and crossed pulmonary arteries is frequent in the presence of a right-sided aortic arch. These findings have important implications for optimal diagnosis and surgical repair.

7.
Pediatr Cardiol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888643

RESUMO

Ideally, the morphology of atrial appendages should solely be used to identify and differentiate patients with isomeric right and left atrial appendages. However, in clinical practice, the segregation is often indirectly based on the arrangement of thoraco-abdominal structures. The correlation between thoraco-abdominal arrangement and atrial appendages, however, is imperfect. In this study, we sought to clarify the cardiovascular malformations in patients with isomeric atrial appendages with an emphasis on atrial-thoracic-abdominal disharmony. A retrospective review of all patients who underwent cardiac CT angiography between January 2014 and June 2023 and identified to have isomeric atrial appendages was performed. Of the 366 cases (median age: 2 years [interquartile range: 11 months-7 years]), 247 (67.5%) patients had isomeric right atrial appendages while 119 (32.5%) patients had isomeric left atrial appendages. In 316 (86.3%) patients, the thoraco-abdominal arrangement was as per atrial appendage morphology while the remaining 50 (13.6%) patients had disharmonious patterns. Compared to isomeric left atrial appendages, the disharmonious pattern was more frequent with isomeric right atrial appendages (5.9% vs. 17.4%; p 0.003). Irrespective of the type of isomerism, disharmony was mostly confined to the level of the abdomen. Not all patients with isomeric atrial appendages have a harmonious thoraco-abdominal arrangement. The atrial-bronchial-abdominal disharmony is more frequent with isomeric right atrial appendages and is mostly present at the level of the abdomen. A detailed sequential segmental analysis with an independent description of each organ system is, therefore, essential for the complete evaluation of patients with isomeric atrial appendages.

8.
Environ Monit Assess ; 196(2): 166, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38233539

RESUMO

In the vicinity of the coast, predominantly groundwater is the sole reliable resource for potable purposes as the surface water sources are highly saline and unfit for human consumption. However, the groundwater in Sagar Island is highly vulnerable to saltwater intrusion. The majority of drinking water comes from government-owned hand pump-equipped tube wells. But during the summer season, many of these tube wells yield significantly less water. Hence, in the current scenario, water quality assessment has become important to the quantity available. Total of 31 samples of deep tube wells (groundwater) are collected at variegated locations during pre-monsoon season throughout Sagar, and then, the physical and chemical quality parameters of these water samples are analysed. Furthermore, a multivariate statistical technique is executed with the aid of the SPSS program. The hydro-chemical parameters that are taken into account for the quality analysis are pH, salinity, electrical conductivity (EC), total dissolved solids (TDS), total hardness, aluminium, arsenic, bi-carbonate, cadmium, iron, chloride, copper, chromium, cobalt, lead, magnesium, manganese, nickel, potassium, sulphate, zinc, and sodium. Then, the analysed data evaluates the water quality index (WQI). Five components are identified through the principal component analysis (PCA) technique, and 82.642% total variance is found. The outcomes of the quality assessment study illustrate that about 54.84% of collected samples come in the "excellent" water quality class when calculated by the "weighted arithmetic WQI method," and 90.32% of collected groundwater samples come in the "good" water quality class when computed using the "modified weighted arithmetic WQI method." This study helps for the interpretation of WQI to assess groundwater quality.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Humanos , Qualidade da Água , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/análise , Índia , Água Potável/análise
9.
Semin Cancer Biol ; 86(Pt 3): 513-531, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35150864

RESUMO

Small secretory proteins of immune cells are mostly Cytokines, which include chemokines, interleukins, interferons, lymphokines and tumor necrosis factors but not hormones or growth factors. These secretory proteins are the molecular messengers and primarily involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Hence, these proteins actually regulate the cells of immune system to communicate with one another to produce a synchronized, robust, still self-regulated response to a specific antigen. Chemokines are smaller secreted proteins that control overall immune cell movement and location; these chemokines are divided into 4 subgroups, namely, CXC, CC, CX3C and C according to the position of 4 conserved cysteine residues. Complete characterization of cytokines and chemokines can exploit their vast signaling networks to develop cancer treatments. These secretory proteins like IL-6, IL-10, IL-12, TNFα, CCL2, CXCL4 & CXCL8 are predominantly expressed in most of the gynecological cancers, which directly stimulate immune effector cells and stromal cells at the tumor site and augment tumor cell recognition by cytotoxic T-cells. Hence; these secretory proteins are the major regulators, which can actually modulate all kinds of gynecological cancers. Furthermore, advancements in adoptive T-cell treatment have relied on the use of multiple cytokines/chemokines to establish a highly regulated environment for anti-tumor T cell growth. A number of in vitro studies as well as animal models and clinical subjects have also shown that cytokines/chemokines have broad antitumor activity, which has been translated into a number of cancer therapy approaches. This review will focus on the foremost cytokines & chemokines involved in the majority of the gynecological malignancies and discuss their basic biology as well as clinical applications.


Assuntos
Quimiocinas , Neoplasias , Animais , Humanos , Quimiocinas/metabolismo , Quimiocinas/uso terapêutico , Citocinas/metabolismo , Neoplasias/etiologia , Neoplasias/tratamento farmacológico , Comunicação Celular , Interleucinas
10.
Semin Cancer Biol ; 86(Pt 2): 1086-1104, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35218902

RESUMO

Recent mounting evidence has revealed extensive genetic heterogeneity within tumors that drive phenotypic variation affecting key cancer pathways, making cancer treatment extremely challenging. Diverse cancer types display resistance to treatment and show patterns of relapse following therapy. Therefore, efforts are required to address tumor heterogeneity by developing a broad-spectrum therapeutic approach that combines targeted therapies. Inflammation has been progressively documented as a vital factor in tumor advancement and has consequences in epigenetic variations that support tumor instigation, encouraging all the tumorigenesis phases. Increased DNA damage, disrupted DNA repair mechanisms, cellular proliferation, apoptosis, angiogenesis, and its incursion are a few pro-cancerous outcomes of chronic inflammation. A clear understanding of the cellular and molecular signaling mechanisms of tumor-endorsing inflammation is necessary for further expansion of anti-cancer therapeutics targeting the crosstalk between tumor development and inflammatory processes. Multiple inflammatory signaling pathways, such as the NF-κB signaling pathway, JAK-STAT signaling pathway, MAPK signaling, PI3K/AKT/mTOR signaling, Wnt signaling cascade, and TGF-ß/Smad signaling, have been found to regulate inflammation, which can be modulated using various factors such as small molecule inhibitors, phytochemicals, recombinant cytokines, and nanoparticles (NPs) in conjugation to phytochemicals to treat cancer. Researchers have identified multiple targets to specifically alter inflammation in cancer therapy to restrict malignant progression and improve the efficacy of cancer therapy. siRNA-and shRNA-loaded NPs have been observed to downregulate STAT3 signaling pathways and have been employed in studies to target tumor malignancies. This review highlights the pathways involved in the interaction between tumor advancement and inflammatory progression, along with the novel approaches of nanotechnology-based drug delivery systems currently used to target inflammatory signaling pathways to combat cancer.


Assuntos
Nanomedicina , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Compreensão , Recidiva Local de Neoplasia , Transdução de Sinais , Inflamação/tratamento farmacológico
11.
J Cell Mol Med ; 27(11): 1603-1607, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37183560

RESUMO

This short communication will enlighten the readers about the exosome and the epithelial-mesenchymal transition (EMT) related to several complicated events. It also highlighted the therapeutic potential of exosomes against EMT. Exosome toxicology, exosome heterogeneity, and a single exosome profiling approach are also covered in this article. In the future, exosomes could help us get closer to cancer vaccine and precision oncology.


Assuntos
Exossomos , Neoplasias , Humanos , Transição Epitelial-Mesenquimal , Transdução de Sinais , Medicina de Precisão
12.
Mol Cancer ; 22(1): 105, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415164

RESUMO

Breast cancer is the second leading cause of death for women worldwide. The heterogeneity of this disease presents a big challenge in its therapeutic management. However, recent advances in molecular biology and immunology enable to develop highly targeted therapies for many forms of breast cancer. The primary objective of targeted therapy is to inhibit a specific target/molecule that supports tumor progression. Ak strain transforming, cyclin-dependent kinases, poly (ADP-ribose) polymerase, and different growth factors have emerged as potential therapeutic targets for specific breast cancer subtypes. Many targeted drugs are currently undergoing clinical trials, and some have already received the FDA approval as monotherapy or in combination with other drugs for the treatment of different forms of breast cancer. However, the targeted drugs have yet to achieve therapeutic promise against triple-negative breast cancer (TNBC). In this aspect, immune therapy has come up as a promising therapeutic approach specifically for TNBC patients. Different immunotherapeutic modalities including immune-checkpoint blockade, vaccination, and adoptive cell transfer have been extensively studied in the clinical setting of breast cancer, especially in TNBC patients. The FDA has already approved some immune-checkpoint blockers in combination with chemotherapeutic drugs to treat TNBC and several trials are ongoing. This review provides an overview of clinical developments and recent advancements in targeted therapies and immunotherapies for breast cancer treatment. The successes, challenges, and prospects were critically discussed to portray their profound prospects.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Imunoterapia/métodos , Terapia Combinada , Terapia de Alvo Molecular/métodos
13.
Mol Cancer ; 22(1): 22, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721153

RESUMO

Malignant brain tumors rank among the most challenging type of malignancies to manage. The current treatment protocol commonly entails surgery followed by radiotherapy and/or chemotherapy, however, the median patient survival rate is poor. Recent developments in immunotherapy for a variety of tumor types spark optimism that immunological strategies may help patients with brain cancer. Chimeric antigen receptor (CAR) T cells exploit the tumor-targeting specificity of antibodies or receptor ligands to direct the cytolytic capacity of T cells. Several molecules have been discovered as potential targets for immunotherapy-based targeting, including but not limited to EGFRvIII, IL13Rα2, and HER2. The outstanding clinical responses to CAR T cell-based treatments in patients with hematological malignancies have generated interest in using this approach to treat solid tumors. Research results to date support the astounding clinical response rates of CD19-targeted CAR T cells, early clinical experiences in brain tumors demonstrating safety and evidence for disease-modifying activity, and the promise for further advances to ultimately assist patients clinically. However, several variable factors seem to slow down the progress rate regarding treating brain cancers utilizing CAR T cells. The current study offers a thorough analysis of CAR T cells' promise in treating brain cancer, including design and delivery considerations, current strides in clinical and preclinical research, issues encountered, and potential solutions.


Assuntos
Neoplasias Encefálicas , Imunoterapia Adotiva , Humanos , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos , Antígenos CD19 , Neoplasias Encefálicas/terapia , Morte Celular , Receptores de Antígenos Quiméricos , Linfócitos T
14.
Curr Issues Mol Biol ; 45(2): 903-917, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36826003

RESUMO

BACKGROUND: Globally, diabetes mellitus is the most common cause of premature mortality after cardiovascular diseases and tobacco chewing. It is a heterogeneous metabolic disorder characterised by the faulty metabolism of carbohydrates, fats and proteins as a result of defects in insulin secretion or resistance. It was estimated that approximately 463 million of the adult population are suffering from diabetes mellitus, which may grow up to 700 million by 2045. Solanum indicum is distributed all over India and all of the tropical and subtropical regions of the world. The different parts of the plant such as the roots, leaves and fruits were used traditionally in the treatment of cough, asthma and rhinitis. However, the hypoglycaemic activity of the plant is not scientifically validated. PURPOSE: The present study aimed to evaluate the antioxidant, antidiabetic and anti-hyperlipidaemic activity of methanolic fruit extract of Solanum indicum (SIE) in streptozotocin (STZ) induced diabetic rats. METHOD: Experimentally, type II diabetes was induced in rats by an i.p. injection of STZ at a dose of 60 mg/kg. The effect of the fruit extract was evaluated at doses of 100 and 200 mg/kg body weight in STZ-induced diabetic rats for 30 days. RESULT: The oral administration of fruit extract caused a significant (p < 0.05) reduction in the blood glucose level with a more prominent effect at 200 mg/kg. The fruit extract showed dose-dependent α-amylase and α-glycosidase inhibitory activity. It reduced the serum cholesterol and triglyceride levels remarkably in diabetic rats compared to normal. The extract showed the reduced activity of endogenous antioxidants, superoxide dismutase, glutathione peroxidase and catalase in the liver of STZ diabetic rats. CONCLUSION: The result confirmed that the fruit extract of Solanum indicum showed a dose-dependent blood glucose lowering effect and significantly reduced elevated blood cholesterol and triglycerides. It prevented oxidative stress associated with type II diabetes in STZ rats.

16.
Biomarkers ; 28(6): 502-518, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37352015

RESUMO

Breast cancer (BC) remains the most challenging global health crisis of the current decade, impacting a large population of females annually. In the field of cancer research, the discovery of extracellular vesicles (EVs), specifically exosomes (a subpopulation of EVs), has marked a significant milestone. In general, exosomes are released from all active cells but tumour cell-derived exosomes (TDXs) have a great impact (TDXs miRNAs, proteins, lipid molecules) on cancer development and progression. TDXs regulate multiple events in breast cancer such as tumour microenvironment remodelling, immune cell suppression, angiogenesis, metastasis (EMT-epithelial mesenchymal transition, organ-specific metastasis), and therapeutic resistance. In BC, early detection is the most challenging event, exosome-based BC screening solved the problem. Exosome-based BC treatment is a sign of the transforming era of liquid biopsy, it is also a promising therapeutic tool for breast cancer. Exosome research goes to closer precision oncology via a single exosome profiling approach. Our hope is that this review will serve as motivation for researchers to explore the field of exosomes and develop an efficient, and affordable theranostics approach for breast cancer.


Assuntos
Neoplasias da Mama , Exossomos , MicroRNAs , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Medicina de Precisão , Relevância Clínica , Exossomos/genética , Exossomos/patologia , Microambiente Tumoral/genética
17.
Org Biomol Chem ; 21(16): 3311-3316, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37000611

RESUMO

A bioinspired mimic for the stabilization of hydroperoxyflavin intermediate formation was designed and investigated for monooxygenase like catalytic properties. A suitable peptide appendage was covalently linked to the C7-position of the neutral isoalloxazine core to synthesize Fl-G, Fl-F, Fl-P, and Fl-ßA analogues. While the presence and identity of the peptide appendage were found to be crucial for catalytic efficiency, corroborative observations were made from theoretical studies as well, supporting the precise conformational and accessibility requirements for the stabilization of the key hydroperoxyflavin intermediate. A simple yet elegant flavopeptide model (Fl-G) was found to achieve almost quantitative catalytic efficiency compared to the control flavin analogue without a peptide appendage.


Assuntos
Oxigenases de Função Mista , Peptídeos , Modelos Moleculares , Oxigenases de Função Mista/metabolismo , Conformação Molecular , Catálise , Flavinas/química , Flavinas/metabolismo , Oxirredução , Cinética
18.
Appl Microbiol Biotechnol ; 107(7-8): 2155-2167, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36922438

RESUMO

Genus Crinum L. is a member of the Amaryllidaceae family having beautiful, huge, ornamental plants with umbels of lily-like blooms that are found in tropical and subtropical climates all over the world. For thousands of years, Crinum has been used as a traditional medicine to treat illnesses and disorders. Numerous distinct alkaloids of the Amaryllidaceae group, whose most well-known properties include analgesic, anticholinergic, antitumor, and antiviral, have recently been discovered by phytochemical analyses. However, because of decades of overexploitation for their economically significant bioactive ingredients and poor seed viability and germination rates, these plants are now threatened in their native environments. Because of these factors, researchers are investigating micropropagation techniques to optimize phytochemicals in vitro. This review's objective is to offer details on the distribution, phytochemistry, micropropagation, in vitro galanthamine synthesis, and pharmacology which will help to design biotechnological techniques for the preservation, widespread multiplication, and required secondary metabolite production from Crinum spp. KEY POINTS: • Botanical description and phytochemical profile of Crinum spp. • In vitro micropropagation method of Crinum sp. • Bioactive compound galanthamine isolation techniques and its pharmacological properties.


Assuntos
Alcaloides , Crinum , Crinum/química , Extratos Vegetais/farmacologia , Galantamina , Alcaloides/química , Compostos Fitoquímicos
19.
Rheumatol Int ; 43(12): 2327-2331, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37430128

RESUMO

Polyarteritis nodosa (PAN) is a medium-vessel vasculitis presenting with cutaneous and multisystem involvement with considerable morbidity. The necrotizing vasculitis in PAN typically involves renal, celiac, and mesenteric vascular beds. Coronary artery involvement is a characteristic feature of Kawasaki disease, another medium-vessel vasculitis; however, it has been rarely reported with PAN. Here, we present 2 cases with PAN involving coronaries mimicking Kawasaki disease. A 3.5-year-old boy with classical features of Kawasaki disease with giant coronary aneurysm refractory to IVIg, methylprednisolone, infliximab presented with persistent rise in inflammatory markers and gastrointestinal bleeding. Digital subtraction angiography (DSA) revealed celiac artery branches stenosis and beading suggestive of PAN. Another 2-year-old girl presented with persistent fever, abdominal pain, and distension. She had hypertension, hepatomegaly, and splenomegaly on examination. Echocardiography revealed multiple coronary aneurysms and DSA revealed numerous renal artery aneurysms. Coronary aneurysm although is a rare presentation of childhood PAN, and can mimic Kawasaki disease. Although both are medium-vessel vasculitis differentiation between these two entities is pivotal, as there are differences in treatment modalities, duration of immunomodulatory therapy, and the outcome. This manuscript describes the salient differences which can help differentiate PAN masquerading as Kawasaki disease at initial presentation.

20.
Mar Drugs ; 21(4)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37103352

RESUMO

Chitin is the second most abundant biopolymer consisting of N-acetylglucosamine units and is primarily derived from the shells of marine crustaceans and the cell walls of organisms (such as bacteria, fungi, and algae). Being a biopolymer, its materialistic properties, such as biodegradability, and biocompatibility, make it a suitable choice for biomedical applications. Similarly, its deacetylated derivative, chitosan, exhibits similar biocompatibility and biodegradability properties, making it a suitable support material for biomedical applications. Furthermore, it has intrinsic material properties such as antioxidant, antibacterial, and antitumor. Population studies have projected nearly 12 million cancer patients across the globe, where most will be suffering from solid tumors. One of the shortcomings of potent anticancer drugs is finding a suitable cellular delivery material or system. Therefore, identifying new drug carriers to achieve effective anticancer therapy is becoming essential. This paper focuses on the strategies implemented using chitin and chitosan biopolymers in drug delivery for cancer treatment.


Assuntos
Antineoplásicos , Quitosana , Nanopartículas , Neoplasias , Humanos , Quitosana/uso terapêutico , Quitina , Sistemas de Liberação de Medicamentos , Biopolímeros , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
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