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1.
Mol Cell ; 84(8): 1475-1495.e18, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38521065

RESUMO

Transcription and splicing of pre-messenger RNA are closely coordinated, but how this functional coupling is disrupted in human diseases remains unexplored. Using isogenic cell lines, patient samples, and a mutant mouse model, we investigated how cancer-associated mutations in SF3B1 alter transcription. We found that these mutations reduce the elongation rate of RNA polymerase II (RNAPII) along gene bodies and its density at promoters. The elongation defect results from disrupted pre-spliceosome assembly due to impaired protein-protein interactions of mutant SF3B1. The decreased promoter-proximal RNAPII density reduces both chromatin accessibility and H3K4me3 marks at promoters. Through an unbiased screen, we identified epigenetic factors in the Sin3/HDAC/H3K4me pathway, which, when modulated, reverse both transcription and chromatin changes. Our findings reveal how splicing factor mutant states behave functionally as epigenetic disorders through impaired transcription-related changes to the chromatin landscape. We also present a rationale for targeting the Sin3/HDAC complex as a therapeutic strategy.


Assuntos
Cromatina , Neoplasias , Animais , Humanos , Camundongos , Cromatina/genética , Mutação , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Splicing de RNA/genética , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo
2.
Curr Issues Mol Biol ; 46(3): 1904-1920, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534740

RESUMO

The SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) virus and the resulting COVID-19 pandemic have had devastating and lasting impact on the global population. Although the main target of the disease is the respiratory tract, clinical outcomes, and research have also shown significant effects of infection on other organ systems. Of interest in this review is the effect of the virus on the cardiovascular system. Complications, including hyperinflammatory syndrome, myocarditis, and cardiac failure, have been documented in the context of COVID-19 infection. These complications ultimately contribute to worse patient outcomes, especially in patients with pre-existing conditions such as hypertension, diabetes, or cardiovascular disease (CVD). Importantly and interestingly, reports have demonstrated that COVID-19 also causes myocardial injury in adults without pre-existing conditions and contributes to systemic complications in pediatric populations, such as the development of multisystem inflammatory syndrome in children (MIS-C). Although there is still a debate over the exact mechanisms by which such complications arise, understanding the potential paths by which the virus can influence the cardiovascular system to create an inflammatory environment may clarify how SARS-CoV-2 interacts with human physiology. In addition to describing the mechanisms of disease propagation and patient presentation, this review discusses the diagnostic findings and treatment strategies and the evolution of management for patients presenting with cardiovascular complications, focusing on disease treatment and prevention.

3.
Chembiochem ; 25(16): e202400162, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38874536

RESUMO

Pain management following acute injury or post-operative procedures is highly necessary for proper recovery and quality of life. Opioids and non-steroidal anti-inflammatory drugs (NSAIDS) have been used for this purpose, but opioids cause addiction and withdrawal symptoms whereas NSAIDS have several systemic toxicities. Derivatives of the naturally occurring iboga alkaloids have previously shown promising behavior in anti-addiction of morphine by virtue of their interaction with opioid receptors. On this frontier, four benzofuran analogs of the iboga family have been synthesized and their analgesic effects have been studied in formalin induced acute pain model in male Swiss albino mice at 30 mg/kg of body weight dose administered intraperitoneally. The antioxidant, anti-inflammatory and neuro-modulatory effects of the analogs were analyzed. Reversal of tail flick latency, restricted locomotion and anxiogenic behavior were observed in iboga alcohol, primary amide and secondary amide. Local neuroinflammatory mediators' substance P, calcitonin gene related peptide, cyclooxygenase-2 and p65 were significantly decreased whereas the depletion of brain derived neurotrophic factor and glia derived neurotrophic factor was overturned on iboga analog treatment. Behavioral patterns after oral administration of the best analog were also analyzed. Taken together, these results show that the iboga family of alkaloid has huge potential in pain management.


Assuntos
Benzofuranos , Modelos Animais de Doenças , Inflamação , Nociceptividade , Animais , Camundongos , Masculino , Benzofuranos/farmacologia , Benzofuranos/química , Benzofuranos/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Nociceptividade/efeitos dos fármacos , Dor Aguda/tratamento farmacológico , Dor Aguda/metabolismo , Analgésicos/farmacologia , Analgésicos/química , Analgésicos/uso terapêutico
4.
J Med Virol ; 96(9): e29924, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39295283

RESUMO

We performed a comparative, retrospective analysis (March 2019-April 2023) of children diagnosed with non-polio enterovirus (NPEV) central nervous system (CNS) infections (n = 47 vs. 129 contemporaneous controls without NPEV, all <18 years old), requiring cerebrospinal fluid (CSF) testing upon presentation to hospital. We found that showed that admissions decreased during pandemic restrictions (13% vs. controls 33%, p = 0.003). The median age of children with NPEV was 41 days (IQR: 18-72), most were male (n = 76, 59%) and were less likely to present with symptoms of irritability (11% vs. controls 26%, p = 0.04), but more likely to be febrile (93% vs. controls 73%, p = 0.007), have higher respiratory rates (mean 44 bpm, SD 11, vs. controls 36 bpm, SD 14, p = 0.001), higher heart rates (mean 171 bpm, SD 27 vs. controls 141 bpm, SD 36, p < 0.001), higher CSF protein (median 0.66 g/L, interquartile range [IQR] 0.46-1.01, vs. controls 0.53 mg/mL, IQR 0.28-0.89, p = 0.04), higher CSF white cell count (WCC) (median WCC 9.5×106/L, IQR 1-16 vs. controls 3.15×106/L, IQR 2.7-3.6, p < 0.001), but lower CSF glucose (median 2.8 mmol/L, IQR 2.4-3.1 vs. controls 3.1 mmol/L, IQR 2.7-3.6, p < 0.001). Phylogenetic analysis showed that these NPEVs originated from Europe (EV A71, CV B4, E21, E6, CV B3, CV B5, E7, E11, E18), North America (CV B4, E18), South America (E6), Middle East (CV B5), Africa (CV B5, E18), South Asia (E15), East/Southeast Asia (E25, CV A9, E7, E11, E18), and Australia (CV B5).


Assuntos
Infecções por Enterovirus , Enterovirus , Epidemiologia Molecular , Humanos , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Infecções por Enterovirus/líquido cefalorraquidiano , Masculino , Feminino , Estudos Retrospectivos , Lactente , Pré-Escolar , Criança , Enterovirus/genética , Enterovirus/isolamento & purificação , Enterovirus/classificação , Filogenia , Recém-Nascido , Líquido Cefalorraquidiano/virologia , Adolescente
5.
Phys Rev Lett ; 132(1): 014001, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38242653

RESUMO

We present a novel generalized scaling framework and predictive model for wall friction in turbulent flows. The scaling is derived from the dynamical equations, and total mean-flow kinetic energy and the velocity profile shape factor are used as surrogates for dynamical and boundary condition effects. Veracity of the present approach is assessed using data from the literature spanning unprecedented ranges of flow types, Reynolds numbers, accelerations, and history effects. Unlike previous models that solely apply to standard flows, the present framework reconciles nonstandard flows with standard flows and enables accurate estimates of wall friction in numerical simulations and experiments without resolving the viscous sublayer or using the law of the wall.

6.
Crit Rev Biotechnol ; : 1-11, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839596

RESUMO

Additives, such as bisphenol A (BPA) that are added to packaging material to enhance functionality may migrate into food products creating a concern for food safety. BPA has been linked to various chronic diseases, such as: diabetes, obesity, prostate cancer, impaired thyroid function, and several other metabolic disorders. To safeguard consumers, BPA migration limits have been defined by regulatory bodies. However, it is important to address the underlying factors and mechanisms so that they can be optimized in order to minimize BPA migration. In this review, we determine the relative importance of the factors, i.e. temperature, contact time, pH, food composition, storage time and temperature, package type, cleaning, and aging, and packaging damage that promote BPA migration in foods. Packaging material seems to be the key source of BPA and the temperature (applied during food production, storage, can sterilization and cleaning processes) was the critical driver influencing BPA migration.

7.
Curr Atheroscler Rep ; 26(11): 639-648, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39240492

RESUMO

PURPOSE OF REVIEW: Health data sciences can help mitigate high burden of cardiovascular disease (CVD) management in South Asia by increasing availability and affordability of healthcare services. This review explores the current landscape, challenges, and strategies for leveraging digital health technologies to improve CVD outcomes in the region. RECENT FINDINGS: Several South Asian countries are implementing national digital health strategies that aim to provide unique health account numbers for patients, creating longitudinal digital health records while others aim to digitize healthcare services and improve health outcomes. Significant challenges impede progress, including lack of interoperability, inadequate training of healthcare workers, cultural barriers, and data privacy concerns. Leveraging digital health for CVD management involves using big data for early detection, employing artificial intelligence for diagnostics, and integrating multiomics data for health insights. Addressing these challenges through policy frameworks, capacity building, and international cooperation is crucial for improving CVD outcomes in region.


Assuntos
Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/terapia , Doenças Cardiovasculares/epidemiologia , Ásia/epidemiologia , Ciência de Dados/métodos , Telemedicina , Big Data , Saúde Digital , Ásia Meridional
8.
J Org Chem ; 89(5): 2895-2903, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38344977

RESUMO

The synthesis of phosphorodiamidate morpholino oligonucleotides (PMOs) incorporating single or double triazole rings in the backbone has been achieved via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The synthetic approach implemented is fundamentally convergent, involving the ligation of a 5'-azide PMO fragment to a 3'-alkyne fragment both in solution and on solid support. To access the 3'-alkyne PMO fragment, we synthesized 3'-N-propargyl chlorophosphoramidate morpholino monomers for all four nucleobases. The resulting triazole-incorporated PMOs (TzPMOs) have exhibited comparable or improved binding affinity toward complementary deoxyribonucleic acid (DNA)/ribonucleic acid (RNA) strands compared to its regular analogues. Finally, a full-length TzPMO was designed to target the Nanog gene, demonstrating almost identical hybridization properties when compared to its regular version. Circular dichroism studies revealed a B-type helical conformation for the duplexes formed by TzPMOs.


Assuntos
Alcinos , Azidas , Morfolinos , Dicroísmo Circular , Triazóis
9.
Inorg Chem ; 63(32): 14811-14815, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39088793

RESUMO

We report square planar mononuclear Pt(II)-complexes of terpyridines in the form of [PtCl(L1/L2)]PF6 as phosphorescent emitters (where L1 = 4-(3-pyridine)2,2':6',2''-terpyridine and L2 = 4'-(3-pyridinyl)-4,4''-di(tert-butyl)-2,2':6'2''-terpyridine). Complex 2 showed emission at 534 nm in the DCM solution with photoluminescence quantum efficiency (ΦPL) = 14%, while in the mCBP host (5-wt % doped), the emission shifted to 584 nm with ΦPL = 37.8% and a phosphorescence lifetime (τphos) of 37.8 µs. Complex 2 in mCBP was used to fabricate a solution-processed phosphorescent organic light-emitting diode (PhOLED) which showed maximum external quantum efficiency (EQEmax) = 7.4% with yellow emission at λEL = 570 nm and exhibited a low efficiency roll-off with an EQE drop to 7.0% at 1000 cd/m2.

10.
J Vector Borne Dis ; 61(1): 29-42, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648404

RESUMO

BACKGROUND OBJECTIVES: In urban areas, upsurge in population has resulted in more breeding sites for malaria vectors, and hence this scenario potentially undermine malaria elimination and control programs. The change in land use due to urbanization may result in the presence and distribution of malaria vectors. Understanding potential malaria vectors is essential for current and future malaria transmission control strategies. This study investigated the effects of rapid urbanization on malaria vectors An. culicifacies s.l. and An. stephensi L. in Ghaziabad district. METHODS: Ghaziabad district which presents several levels of urbanization was selected for this study. Entomological investigations were conducted seasonally from 2014-2016 in the rural, urban, and peri-urban regions. Vector incrimination study was done using ELISA (confirmation by PCR) on suspected Anopheles vectors viz. An. culicifacies, An. stephensi, An. annularis and An. subpictus. RESULTS: An. culicifacies showed alteration in distribution influenced by rural and agricultural land whereas An. stephensi was found to be influenced by artificial habitats and population growth. INTERPRETATION CONCLUSION: The study also confirms the association between the abundance of malaria vectors and land use change.


Assuntos
Anopheles , Malária , Mosquitos Vetores , Urbanização , Anopheles/fisiologia , Anopheles/crescimento & desenvolvimento , Índia/epidemiologia , Animais , Mosquitos Vetores/fisiologia , Mosquitos Vetores/crescimento & desenvolvimento , Malária/transmissão , Malária/epidemiologia , Estações do Ano , Ecossistema , Humanos , População Rural , Distribuição Animal
11.
Cutan Ocul Toxicol ; 43(3): 211-226, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39024063

RESUMO

The process of skin ageing is a natural biological phenomenon characterised by the emergence of wrinkles, age spots, sagging skin, and dryness over time. The increasing significance of skin in physical attractiveness has heightened skincare concerns. Anti-ageing cosmetics play a pivotal role in nurturing the skin, enhancing its quality, and promoting overall health. Today, cosmetics have evolved beyond mere aesthetics and are now integral to individual wellness. The contemporary quest for perpetual youth has intensified, prompting a deeper exploration into the skin ageing process. This comprehensive exploration delves into various elements involved in skin ageing, encompassing cells such as stem and endothelial cells, blood vessels, soft tissues, and signalling pathways. The molecular basis of skin ageing, including biochemical factors like reactive oxygen species, damaged DNA, free radicals, ions, and proteins (mRNA), is scrutinised alongside relevant animal models. The article critically analyzes the outcomes of utilising herbal components, emphasising their advantageous anti-ageing properties. The factors contributing to skin ageing, mechanistic perspectives, management approaches involving herbal cosmeceutical, and associated complications (especially cardiovascular diseases, Parkinson's, Alzheimer's, etc.) are succinctly addressed. In addition, the manuscript further summarises the recent patented innovations and toxicity of the herbal cosmeceuticals for anti-ageing and ageing associated disorders. Despite progress, further research is imperative to unlock the full potential of herbal components as anti-ageing agents.


Assuntos
Cosmecêuticos , Envelhecimento da Pele , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Cosmecêuticos/uso terapêutico , Animais , Cosméticos , Pele/efeitos dos fármacos , Pele/patologia , Pele/metabolismo , Preparações de Plantas/uso terapêutico , Preparações de Plantas/farmacologia
12.
J Assoc Physicians India ; 72(9S): 38-39, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39291573

RESUMO

Pulmonary edema, either cardiogenic or noncardiogenic, is caused by fluid accumulation in the alveolar spaces. Cardiogenic pulmonary edema (CPE), one of the causes of congestive heart failure (CHF), is treated with loop diuretics. Torsemide and furosemide were found to be useful in the treatment of CHF-associated pulmonary edema due to their ability to lower pulmonary capillary pressure and left ventricular end-diastolic pressure, respectively. Pharmacological features of torsemide, such as greater bioavailability, higher absorption rate, and efficacy, make it a better alternative for treating pulmonary edema than the regularly used loop diuretic, furosemide. Torsemide administered intravenously was found to be both efficacious and well tolerated in CPE. However, more research is needed to determine its usefulness in non-CPE.


Assuntos
Insuficiência Cardíaca , Edema Pulmonar , Inibidores de Simportadores de Cloreto de Sódio e Potássio , Torasemida , Humanos , Furosemida/farmacologia , Furosemida/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/complicações , Edema Pulmonar/tratamento farmacológico , Edema Pulmonar/etiologia , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Torasemida/farmacologia , Torasemida/uso terapêutico
13.
Gen Dent ; 72(3): 34-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38640004

RESUMO

The majority of problematic conditions resulting from dental implant treatment are inflammatory in character, but certain isolated occurrences of primary oral squamous cell carcinoma (OSCC) have been discovered in the area of implants. The goal of this study was to examine whether there is a link between dental implants and the development of OSCC in patients who have a history of a potentially malignant lesion (PML) or malignancy. Using the keywords "carcinoma" AND "dental implants," a search was conducted in the MEDLINE (PubMed), National Center for Biotechnology Information, and Google Scholar databases for case reports and case series in which OSCC was discovered as a primary cancer in the region of dental implants. An initial search identified 260 articles, 247 of which were excluded based on study inclusion or exclusion criteria, leaving 13 articles chosen for inclusion and a total of 30 patients who developed primary oral cancer surrounding osseointegrated titanium-based dental implants. In the studies included in the present review, 22 (73%) of 30 patients with peri-implant cancer had a history of PML or carcinoma. There is no statistical evidence of a direct association between dental implants and OSCC in patients with a history of a PML or malignant lesion. There have been some case reports of OSCC in the region of dental implants in patients with a history of a PML or malignant lesion, but further studies are needed to prove a definitive relationship.


Assuntos
Carcinoma de Células Escamosas , Implantes Dentários , Neoplasias Bucais , Humanos , Implantes Dentários/efeitos adversos , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/etiologia
14.
J Biol Chem ; 298(9): 102347, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35963433

RESUMO

Cell death-inducing DNA fragmentation factor-like effector C (CIDEC) expression in adipose tissue positively correlates with insulin sensitivity in obese humans. Further, E186X, a single-nucleotide CIDEC variant is associated with lipodystrophy, hypertriglyceridemia, and insulin resistance. To establish the unknown mechanistic link between CIDEC and maintenance of systemic glucose homeostasis, we generated transgenic mouse models expressing CIDEC (Ad-CIDECtg) and CIDEC E186X variant (Ad-CIDECmut) transgene specifically in the adipose tissue. We found that Ad-CIDECtg but not Ad-CIDECmut mice were protected against high-fat diet-induced glucose intolerance. Furthermore, we revealed the role of CIDEC in lipid metabolism using transcriptomics and lipidomics. Serum triglycerides, cholesterol, and low-density lipoproteins were lower in high-fat diet-fed Ad-CIDECtg mice compared to their littermate controls. Mechanistically, we demonstrated that CIDEC regulates the enzymatic activity of adipose triglyceride lipase via interacting with its activator, CGI-58, to reduce free fatty acid release and lipotoxicity. In addition, we confirmed that CIDEC is indeed a vital regulator of lipolysis in adipose tissue of obese humans, and treatment with recombinant CIDEC decreased triglyceride breakdown in visceral human adipose tissue. Our study unravels a central pathway whereby adipocyte-specific CIDEC plays a pivotal role in regulating adipose lipid metabolism and whole-body glucose homeostasis. In summary, our findings identify human CIDEC as a potential 'drug' or a 'druggable' target to reverse obesity-induced lipotoxicity and glucose intolerance.


Assuntos
Intolerância à Glucose , Resistência à Insulina , Animais , Colesterol , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos não Esterificados , Glucose , Intolerância à Glucose/genética , Intolerância à Glucose/prevenção & controle , Humanos , Resistência à Insulina/genética , Lipase/genética , Metabolismo dos Lipídeos , Lipoproteínas LDL/metabolismo , Camundongos , Nucleotídeos/metabolismo , Obesidade/genética , Proteínas/metabolismo , Transgenes , Triglicerídeos
15.
J Am Chem Soc ; 145(3): 1945-1954, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36638828

RESUMO

The design and regulation of multiple room-temperature phosphorescence (RTP) processes are formidably challenging due to the restrictions imposed by Kasha's rule. Here, we report a general design principle for materials that show multiple RTP processes, which is informed by our study of four compounds where there is modulation of the linker hybridization between donor (D) and acceptor (A) groups. Theoretical modeling and photophysical experiments demonstrate that multiple RTP processes can be achieved in sp3 C-linked D-A compounds due to the arrest of intramolecular electronic communication between two triplet states (T1H and T1L) localized on the donor and acceptor or between two triplet states, one localized on the donor and one delocalized across aggregated acceptors. However, for the sp2 C-linked D-A counterparts, RTP from one locally excited T1 state is observed because of enhanced excitonic coupling between the two triplet states of molecular subunits. Single-crystal and reduced density gradient analyses reveal the influence of molecular packing on the coincident phosphorescence processes and the origin of the observed aggregate phosphorescence. These findings provide insights into higher-lying triplet excited-state dynamics and into a fundamental design principle for designing compounds that show multiple RTP.

16.
Chemistry ; 29(55): e202301749, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37432103

RESUMO

A novel organocatalyzed [3+2] cycloaddition reaction of nitroolefins with glycosyl azides as well as organic azides has been developed for successful construction of 1,5-disubstituted triazolyl glycoconjugates. This metal-free and acid-free, regioselective synthetic protocol proceeds in the presence of only Schreiner thiourea organocatalysts, which enable the required activation of nitroolefins through double hydrogen bonding. The straightforward, operationally simple, and regioselectivity of this methodology, complementing to the classical RuAAC catalyzed synthesis of 1,5-disubstituted 1,2,3-triazoles. In the presence of catalytic amount of Schreiner thiourea organocatalyst, organic azides react with a broad array of nitroolefins producing a series of diverse 1,5-disubstituted 1,2,3- triazoles in good yields with excellent regioselectivity.

17.
Langmuir ; 39(11): 3905-3913, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36881384

RESUMO

Magnetic resonance imaging (MRI) relaxometry and diffusion methods were used to highlight the instability mechanisms of oil-in-water Pickering emulsions stabilized by cellulose nanofibers (CNFs). Four different Pickering emulsions using different oils (n-dodecane and olive oil) and concentrations of CNFs (0.5 and 1.0 wt %) were systematically investigated over a period of one month after emulsification. The separation into a free oil, emulsion layer, and serum layer and the distribution of flocculated/coalesced oil droplets in several hundred micrometers were captured in MR images using fast low-angle shot (FLASH) and rapid acquisition with relaxation enhancement (RARE) sequences. The components of the Pickering emulsions (e.g., free oil, emulsion layer, oil droplets, and serum layer) were observable by different voxelwise relaxation times and apparent diffusion coefficients (ADCs) and reconstructing in the apparent T1, T2, and ADC maps. The mean T1, T2, and ADC of the free oil and serum layer corresponded well with MRI results for pure oils and water, respectively. Comparing the relaxation properties and translational diffusion coefficients of pure dodecane and olive oil obtained from NMR and MRI resulted in similar T1 and ADC but significantly different T2 depending on the sequence used. The diffusion coefficients of olive oil measured by NMR were much slower than dodecane. The ADC of the emulsion layer for dodecane emulsions did not correlate with the viscosity of the emulsions as the CNF concentration increased, suggesting the effects of restricted diffusion of oil/water molecules due to droplet packing.

18.
J Org Chem ; 88(19): 13440-13453, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37747895

RESUMO

This report describes a convenient method for the Cu(I)-catalyzed Sonogashira cross-coupling reaction of aryl/heteroaryl halides and alkynyl sugars in the presence of a 1,2,3-triazole-appended glycohybrid as a biocompatible ligand. The Sonogashira cross-coupling products were exclusively formed without the Glaser-Hay homocoupling reaction in the presence of a glycosyl monotriazolyl ligand at 120 °C. However, the Glaser-Hay homocoupling products were obtained at 60-70 °C in the presence of bis-triazolyl-based macrocyclic glycohybrid ligand L8. The glycosyl triazole ligands were synthesized via the CuI/DIPEA-mediated regioselective CuAAC click reaction, and a series of glycohybrids of glucose, mannose, and galactose alkynes including glycosyl rods were developed in good yields. The developed glycohybrids have been well characterized by various spectroscopic techniques, such as nuclear magnetic resonance, high-resolution mass spectrometry, and single-crystal X-ray data of L3. The protocol works well with the heteroaryl and naphthyl halides, and the mechanistic approach leads to CuI/ligand-assisted oxidative coupling. The coupling protocol has notable features, including low catalytic loading, cost-effectiveness, biocompatible nature, and a wide substrate scope.

19.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203673

RESUMO

Delivery systems for biologically active substances such as proanthocyanidins (PCANs), produced in the form of electrospun nonwoven through the electrospinning method, were designed using a polymeric blend of poly(L-lactide-co-glycolide) (PLGA)and poly[(R,S)-3-hydroxybutyrate] ((R,S)-PHB). The studies involved the structural and thermal characteristics of the developed electrospun three-dimensional fibre matrices unloaded and loaded with PCANs. In the next step, the hydrolytic degradation tests of these systems were performed. The release profile of PCANs from the electrospun nonwoven was determined with the aid of UV-VIS spectroscopy. Approximately 30% of the PCANs were released from the tested electrospun nonwoven during the initial 15-20 days of incubation. The chemical structure of water-soluble oligomers that were formed after the hydrolytic degradation of the developed delivery system was identified through electrospray ionization mass spectrometry. Oligomers of lactic acid and OLAGA oligocopolyester, as well as oligo-3-hydroxybutyrate terminated with hydroxyl and carboxyl end groups, were recognized as degradation products released into the water during the incubation time. It was also demonstrated that variations in the degradation rate of individual mat components influenced the degradation pattern and the number of formed oligomers. The obtained results suggest that the incorporation of proanthocyanidins into the system slowed down the hydrolytic degradation process of the poly(L-lactide-co-glycolide)/poly[(R,S)-3-hydroxybutyrate] three-dimensional fibre matrix. In addition, in vitro cytotoxicity and antimicrobial studies advocate the use of PCANs for biomedical applications with promising antimicrobial activity.


Assuntos
Anti-Infecciosos , Proantocianidinas , Humanos , Poliésteres , Bolsa Periodontal , Ácido 3-Hidroxibutírico , Sistemas de Liberação de Medicamentos , Anti-Infecciosos/farmacologia , Hidroxibutiratos , Poli A , Água
20.
Am J Orthod Dentofacial Orthop ; 164(2): 253-264, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36959013

RESUMO

INTRODUCTION: Treating a Class III malocclusion is often challenging for orthodontists. Bone-anchored maxillary protraction (BAMP) is known for achieving a significant maxillary protraction. The study aimed to evaluate the stress distribution and displacement of craniofacial bones as a reaction to the forces of BAMP, along with rapid maxillary expander and the posterior bite plane, in growing patients with skeletal Class III malocclusion using a finite element method. METHODS: An finite element model was constructed from the spiral computed tomographic images of a skull from an 11-year-old growing patient with skeletal Class III malocclusion along with BAMP, rapid maxillary expander, and the posterior bite plane. The created model had 105,189 nodes and 481,066 elements. After assigning the appropriate material properties and the boundary condition, 800 g of transverse force per side and a Class III intraoral elastic 250 g of force per side were applied to the model, and after the postprocessing, the results were obtained in the form of color bands. RESULTS: The maxilla and the attached structures were displaced and expanded transversely. The maxilla was displaced anteriorly by 0.692 mm, and the mandible was displaced backward by 0.204 mm in the sagittal direction. The anterior region of the maxilla and mandible, dentition, and nasal bone were rotated counterclockwise. Displacement in an upward direction was greatest at the symphysis region of the mandible. The stresses experienced by most of the bones were tensile, with the maxilla and maxillary dentition experiencing the maximum. CONCLUSIONS: Favorable changes were appreciated with maxillary forward and mandibular backward displacement, with appreciable tensile stresses in all the bones.


Assuntos
Má Oclusão Classe III de Angle , Maxila , Humanos , Criança , Maxila/diagnóstico por imagem , Análise de Elementos Finitos , Técnica de Expansão Palatina , Crânio , Má Oclusão Classe III de Angle/diagnóstico por imagem , Má Oclusão Classe III de Angle/terapia , Cefalometria/métodos
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