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1.
BMC Musculoskelet Disord ; 25(1): 331, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725009

RESUMO

BACKGROUND: The development of neuropathic pain (NP) is one of the reasons why the pain is difficult to treat, and microglial activation plays an important role in NP. Recently, platelet-rich plasma (PRP) has emerged as a novel therapeutic method for knee osteoarthritis (KOA). However, it's unclarified whether PRP has analgesic effects on NP induced by KOA and the underlying mechanisms unknown. PURPOSE: To observe the analgesic effects of PRP on NP induced by KOA and explore the potential mechanisms of PRP in alleviating NP. METHODS: KOA was induced in male rats with intra-articular injections of monosodium iodoacetate (MIA) on day 0. The rats received PRP or NS (normal saline) treatment at days 15, 17, and 19 after modeling. The Von Frey and Hargreaves tests were applied to assess the pain-related behaviors at different time points. After euthanizing the rats with deep anesthesia at days 28 and 42, the corresponding tissues were taken for subsequent experiments. The expression of activating transcription factor 3 (ATF3) in dorsal root ganglia (DRG) and ionized-calcium-binding adapter molecule-1(Iba-1) in the spinal dorsal horn (SDH) was detected by immunohistochemical staining. In addition, the knee histological assessment was performed by hematoxylin-eosin (HE) staining. RESULTS: The results indicated that injection of MIA induced mechanical allodynia and thermal hyperalgesia, which could be reversed by PRP treatment. PRP downregulated the expression of ATF3 within the DRG and Iba-1 within the SDH. Furthermore, an inhibitory effect on cartilage degeneration was observed in the MIA + PRP group only on day 28. CONCLUSION: These results indicate that PRP intra-articular injection therapy may be a potential therapeutic agent for relieving NP induced by KOA. This effect could be attributed to downregulation of microglial activation and reduction in nerve injury.


Assuntos
Regulação para Baixo , Microglia , Neuralgia , Osteoartrite do Joelho , Plasma Rico em Plaquetas , Ratos Sprague-Dawley , Animais , Masculino , Neuralgia/terapia , Neuralgia/metabolismo , Microglia/metabolismo , Ratos , Osteoartrite do Joelho/terapia , Fator 3 Ativador da Transcrição/metabolismo , Gânglios Espinais/metabolismo , Modelos Animais de Doenças , Injeções Intra-Articulares , Proteínas de Ligação ao Cálcio/metabolismo , Ácido Iodoacético/toxicidade , Proteínas dos Microfilamentos
2.
J Gerontol Nurs ; 50(5): 43-49, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38691116

RESUMO

PURPOSE: To explore care requirements of older adults with urinary incontinence (UI) and contributing factors. METHOD: This cross-sectional study used the Older Adults Urinary Incontinence Care Needs Inventory to survey participants with UI in three large-scale tertiary hospitals located in Guangzhou City, China, from January 2023 to November 2023. Statistical analyses, including analysis of variance, t tests, correlation analyses, and linear regression models, were conducted to assess factors influencing participants' care needs. RESULTS: A total of 530 older adults with UI participated in the survey and mean standardized score for overall care needs was 78.65 (SD = 5.01), with mean scores for each dimension ranging from 70.88 (SD = 10.55) for social participation needs to 82.45 (SD = 7.11) for health education needs. Factors that were found to influence incontinence care needs in older adults included age, literacy level, number of leaks, and type of disease (F = 37.07, adjusted R2 = 0.290, p < 0.001). CONCLUSION: Comprehensive care for older adults with UI, encompassing physiological, psychological, and social aspects, is crucial. It is essential to tailor care to individual needs and characteristics, taking into account factors, such as age and education, to ensure effective care. [Journal of Gerontological Nursing, 50(5), 43-49.].


Assuntos
Incontinência Urinária , Humanos , Incontinência Urinária/enfermagem , Estudos Transversais , Idoso , Feminino , Masculino , Idoso de 80 Anos ou mais , China , Pessoa de Meia-Idade , Inquéritos e Questionários , Avaliação das Necessidades , Necessidades e Demandas de Serviços de Saúde
3.
J Oral Rehabil ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717032

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) derived from the synovium, known as synovium mesenchymal stem cells (SMSCs), exhibit significant potential for articular cartilage regeneration owing to their capacity for chondrogenic differentiation. However, the microRNAs (miRNAs) governing this process and the associated mechanisms remain unclear. While mechanical stress positively influences chondrogenesis in MSCs, the miRNA-mediated response of SMSCs to mechanical stimuli is not well understood. OBJECTIVE: This study explores the miRNA-driven mechano-transduction in SMSCs chondrogenesis under mechanical stress. METHODS: The surface phenotype of SMSCs was analysed by flow cytometry. Chondrogenesis capacities of SMSCs were examined by Alcian blue staining. High throughput sequencing was used to screen mechano-sensitive miRNAs of SMSCs. The RNA expression level of COL2A1, ACAN, SOX9, BMPR2 and miR-143-3p of SMSCs were tested by quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miR-143-3p and TLR4 was confirmed by luciferase reporter assays. The protein expression levels of related genes were assessed by western blot. RESULTS: High-throughput sequencing revealed a notable reduction in miR-143-3p levels in mechanically stressed SMSCs. Gain- or loss-of-function strategies introduced by lentivirus demonstrated that miR-143-3p overexpression hindered chondrogenic differentiation, whereas its knockdown promoted this process. Bioinformatics scrutiny and luciferase reporter assays pinpointed a potential binding site for miR-143-3p within the 3'-UTR of bone morphogenetic protein receptor type 2 (BMPR2). MiR-143-3p overexpression decreased BMPR2 expression and phosphorylated Smad1, 5 and 8 levels, while its inhibition activated BMPR2-Smad pathway. CONCLUSION: This study elucidated that miR-143-3p negatively regulates SMSCs chondrogenic differentiation through the BMPR2-Smad pathway under mechanical tensile stress. The direct targeting of BMPR2 by miR-143-3p established a novel dimension to our understanding of mechano-transduction mechanism during SMSC chondrogenesis. This understanding is crucial for advancing strategies in articular cartilage regeneration.

4.
World J Gastroenterol ; 30(16): 2272-2280, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38690021

RESUMO

BACKGROUND: The magnetic compression technique has been used to establish an animal model of tracheoesophageal fistula (TEF), but the commonly shaped magnets present limitations of poor homogeneity of TEF and poor model control. We designed a T-shaped magnet system to overcome these problems and verified its effectiveness via animal experiments. AIM: To investigate the effectiveness of a T-shaped magnet system for establishing a TEF model in beagle dogs. METHODS: Twelve beagles were randomly assigned to groups in which magnets of the T-shaped scheme (study group, n = 6) or normal magnets (control group, n = 6) were implanted into the trachea and esophagus separately under gastroscopy. Operation time, operation success rate, and accidental injury were recorded. After operation, the presence and timing of cough and the time of magnet shedding were observed. Dogs in the control group were euthanized after X-ray and gastroscopy to confirm establishment of TEFs after coughing, and gross specimens of TEFs were obtained. Dogs in the study group were euthanized after X-ray and gastroscopy 2 wk after surgery, and gross specimens were obtained. Fistula size was measured in all animals, and then harvested fistula specimens were examined by hematoxylin and eosin (HE) and Masson trichrome staining. RESULTS: The operation success rate was 100% for both groups. Operation time did not differ between the study group (5.25 min ± 1.29 min) and the control group (4.75 min ± 1.70 min; P = 0.331). No bleeding, perforation, or unplanned magnet attraction occurred in any animal during the operation. In the early postoperative period, all dogs ate freely and were generally in good condition. Dogs in the control group had severe cough after drinking water at 6-9 d after surgery. X-ray indicated that the magnets had entered the stomach, and gastroscopy showed TEF formation. Gross specimens of TEFs from the control group showed the formation of fistulas with a diameter of 4.94 mm ± 1.29 mm (range, 3.52-6.56 mm). HE and Masson trichrome staining showed scar tissue formation and hierarchical structural disorder at the fistulas. Dogs in the study group did not exhibit obvious coughing after surgery. X-ray examination 2 wk after surgery indicated fixed magnet positioning, and gastroscopy showed no change in magnet positioning. The magnets were removed using a snare under endoscopy, and TEF was observed. Gross specimens showed well-formed fistulas with a diameter of 6.11 mm ± 0.16 mm (range, 5.92-6.36 mm), which exceeded that in the control group (P < 0.001). Scar formation was observed on the internal surface of fistulas by HE and Masson trichrome staining, and the structure was more regular than that in the control group. CONCLUSION: Use of the modified T-shaped magnet scheme is safe and feasible for establishing TEF and can achieve a more stable and uniform fistula size compared with ordinary magnets. Most importantly, this model offers better controllability, which improves the flexibility of follow-up studies.


Assuntos
Modelos Animais de Doenças , Imãs , Traqueia , Fístula Traqueoesofágica , Animais , Cães , Fístula Traqueoesofágica/cirurgia , Fístula Traqueoesofágica/patologia , Fístula Traqueoesofágica/etiologia , Traqueia/cirurgia , Traqueia/patologia , Esôfago/cirurgia , Esôfago/patologia , Esôfago/diagnóstico por imagem , Gastroscopia/instrumentação , Gastroscopia/métodos , Duração da Cirurgia , Masculino , Magnetismo/instrumentação , Desenho de Equipamento , Humanos
5.
Genomics ; 116(3): 110846, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642856

RESUMO

Period circadian regulator 3 (PER3) functions as a tumor suppressor in various cancers. However, the role of PER3 in multiple myeloma (MM) has not been reported yet. Through this study, we aimed to investigate the potential role of PER3 in MM and the underlying mechanisms. RT-qPCR and western blotting were used to determine the mRNA and protein expression levels of PER3. Glyoxylate reductase 1 homolog (GLYR1) was predicted to be a transcription factor of PER3. The binding sites of GLYR1 on the promoter region of PER3 were analyzed using UCSC and confirmed using luciferase and chromatin immunoprecipitation assays. Viability, apoptosis, and metathesis were determined using CCK-8, colony formation, TUNEL, and transwell assays. We found that PER3 expression decreased in MM. Low PER3 levels may predict poor survival rates; PER3 overexpression suppresses the viability and migration of MM cells and promotes apoptosis. Moreover, GLYR1 transcriptionally activates PER3, and the knockdown of PER3 alleviates the effects of GLYR1 and induces its malignant behavior in MM cells. To conclude, GLYR1 upregulates PER3 and suppresses the aggressive behavior of MM cells, suggesting that GLYR1/PER3 signaling may be a potential therapeutic target for MM.

6.
Comput Struct Biotechnol J ; 23: 1408-1417, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38616962

RESUMO

Utilizing α,ß-unsaturated carbonyl group as Michael acceptors to react with thiols represents a successful strategy for developing KRASG12C inhibitors. Despite this, the precise reaction mechanism between KRASG12C and covalent inhibitors remains a subject of debate, primarily due to the absence of an appropriate residue capable of deprotonating the cysteine thiol as a base. To uncover this reaction mechanism, we first discussed the chemical reaction mechanism in solvent conditions via density functional theory (DFT) calculation. Based on this, we then proposed and validated the enzymatic reaction mechanism by employing quantum mechanics/molecular mechanics (QM/MM) calculation. Our QM/MM analysis suggests that, in biological conditions, proton transfer and nucleophilic addition may proceed through a concerted process to form an enolate intermediate, bypassing the need for a base catalyst. This proposed mechanism differs from previous findings. Following the formation of the enolate intermediate, solvent-assisted tautomerization results in the final product. Our calculations indicate that solvent-assisted tautomerization is the rate-limiting step in the catalytic cycle under biological conditions. On the basis of this reaction mechanism, the calculated kinact/ki for two inhibitors is consistent well with the experimental results. Our findings provide new insights into the reaction mechanism between the cysteine of KRASG12C and the covalent inhibitors and may provide valuable information for designing effective covalent inhibitors targeting KRASG12C and other similar targets.

7.
World J Clin Cases ; 12(10): 1766-1771, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38660079

RESUMO

BACKGROUND: Hepatitis B rarely leads to demyelinating neuropathy, despite peripheral neuropathy being the first symptom of hepatitis B infection. CASE SUMMARY: A 64-year-old man presented with sensorimotor symptoms in multiple peripheral nerves. Serological testing showed that these symptoms were due to hepatitis B. After undergoing treatment involving intravenous immunoglobulin and an antiviral agent, there was a notable improvement in his symptoms. CONCLUSION: Although hepatitis B virus (HBV) infection is known to affect hepatocytes, it is crucial to recognize the range of additional manifestations linked to this infection. The connection between long-term HBV infection and demyelinating neuropathy has seldom been documented; hence, prompt diagnostic and treatment are essential. The patient's positive reaction to immunoglobulin seems to be associated with production of the antigen-antibody immune complex.

8.
Front Physiol ; 15: 1345836, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651047

RESUMO

Mylabris sibirica is a hypermetamorphic insect whose adults feed on oilseed rape. However, due to a shortage of effective and appropriate endogenous references, studies on molecular functional genes in Mylabris sibirica, have been tremendously limited. In this study, ten internal reference genes (ACT, ARF1, AK, EF1α, GAPDH, α-TUB, RPL6, RPL13, RPS3 and RPS18) were tested and assessed under four selected treatments including adult ages, adult tissues, temperatures, and sex by RT-qPCR based on five methods (Ct value, geNorm, NormFinder, BestKeeper and RefFinder). Our findings showed that RPL6 and RPL13 were the most optimal internal reference gene combination for gene expression during various adult ages and under diverse temperatures; The combination of RPL6 and RPS18 was recommended to test gene transcription levels under different adult tissues. AK and RPL6 were the best reference genes in male and female adults. RPL6 and RPL13 were the most appropriate reference gene pair to estimate gene expression levels under four different tested backgrounds. The relative transcript levels of a uridine diphosphate (UDP)-N-acetylglucosamine-pyrophosphorylase (MsUAP), varied greatly according to normalization with the two most- and least-suited reference genes. This study will lay the basis for further molecular physiology and biochemistry studies in M. sibirica, such as development, reproduction, sex differentiation, cold and heat resistance.

9.
J Sci Food Agric ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619986

RESUMO

BACKGROUND: Sea buckthorn has the functions of antioxidation, antitumor, anti-inflammation and regulating energy metabolism. In order to investigate the effects of sea buckthorn powder and sea buckthorn flavonoids on the antioxidant properties, immune function and muscle fatty acid composition of common carp, an oral feeding experiment was carried out. RESULTS: The administration of glucose significantly reduced the levels of glutathione and the activity of total antioxidant capacity enzyme in serum and hepatopancreas, while concurrently upregulating the level of malondialdehyde (MDA)(P < 0.05). Conversely, oral intake of sea buckthorn powder and flavonoids increased antioxidant enzyme activity and decreased MDA levels. In terms of antioxidant molecular indicators, sea buckthorn powder and sea buckthorn flavonoids significantly increased the mRNA levels of nuclear factor NF-E2-related factor (nrf2) in the hepatopancreas and muscle. Meanwhile, mRNA expression levels of downstream antioxidant-related genes (gr, cat, gpx, and sod) regulated by Nrf2 were also upregulated. In the immune aspects, the mRNA expression levels of proinflammatory cytokines, such as interleukin-6 (il-6), interleukin-1ß (il-1ß) and nuclear factor-κB (nf-κb), were reduced but the expressions of anti-inflammatory cytokines, such as growth factor-ß (tgf-ß) and interleukin-10 (il-10), were enhanced in the head kidney and spleen tissues after oral administration with sea buckthorn. In terms of muscle fatty acid composition, the ratio of n-3 polyunsaturated fatty acid (PUFA)/n-6 PUFA was notably higher after administering sea buckthorn flavonoids than that of the glucose group (P < 0.05). CONCLUSION: This study demonstrated that oral administration of sea buckthorn powder and sea buckthorn flavonoids significantly enhanced the antioxidant capacity and immune response and improved the muscle fatty acid compositions in common carp, and also mitigated the adverse effects of glucose treatment to a certain extent. © 2024 Society of Chemical Industry.

10.
Chemistry ; : e202400566, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642049

RESUMO

The prosperity of the lithium-ion battery market is inevitably accompanied by the depletion of corresponding resources and the accumulation of spent batteries in a dialectical manner. Spent lithium-ion batteries are harboring the characteristics of hazardous waste and high-value resources, so efficient recycling is of great significance. The cathode material is considered as an interesting target for repurposing. Despite some important reviews give commendable emphasis to recycling technologies, there is still a dearth of exploration of recycling mechanisms. This deficiency of awareness highlights the need for further research and development in this area. This review aims to systematically review and thoroughly discuss the reduction reaction mechanism of each method regarding different cathode materials. And systematically digest the selection of reducing agent and the effect of reduction reaction on material regeneration are systematically digested, as well as the impact of the reduction reaction on the regeneration of materials. This review emphasizes the importance of balancing efficiency, economic and environmental benefits in reuse technologies. Finally, the review proposes an outlook on the opportunities and challenges facing the reuse of key materials for next-generation spent batteries aimed at promoting the green and sustainable development of lithium-ion batteries, circular economy and ecological balance.

12.
HLA ; 103(4): e15483, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605645

RESUMO

HLA-DPB1*1500:01N differs from HLA-DPB1*05:01:01:01 by one nucleotide in exon 3.


Assuntos
Cadeias beta de HLA-DP , Nucleotídeos , Humanos , Alelos , Sequência de Bases , China , Análise de Sequência de DNA
13.
World J Gastrointest Surg ; 16(3): 860-870, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577092

RESUMO

BACKGROUND: Despite much work having been conducted on magnetic compression anastomosis (MCA) in the digestive tract, there are no reports on the influence of magnetic force on the anastomosis. AIM: To investigate the effect of different magnetic force magnets on the MCA of the digestive tract. METHODS: Two groups of magnets of the same sizes but different magnetic forces were designed and produced. A total of 24 Sprague-Dawley rats were randomly assigned into two groups (powerful magnet group and common magnet group), with 12 rats in each group. Two types of magnets were used to complete the colonic side-to-side anastomosis of the rats. The operation time and magnet discharge time were recorded. The anastomotic specimens were obtained 4 wk after the operation and then the burst pressure and diameter of the anastomosis were measured, and the anastomosis was observed via the naked eye and subjected to histological examination. RESULTS: The magnetic forces of the powerful and common magnet groups at zero distance were 8.26 N and 4.10 N, respectively. The colonic side-to-side anastomosis was completed in all 24 rats, and the operation success rate and postoperative survival rate were 100%. No significant difference was noted in the operation time between the two groups. The magnet discharge time of the powerful magnet group was slightly longer than that of the common magnet group, but the difference was not statistically significant (P = 0.513). Furthermore, there was no statistical difference in the burst pressure (P = 0.266) or diameter of magnetic anastomosis (P = 0.095) between the two groups. The gross specimens of the two groups showed good anastomotic healing, and histological observation indicated good mucosal continuity without differences on healing. CONCLUSION: In the rat colonic side-to-side MCA model, both the powerful magnet with 8.26 N and the common magnet with 4.10 N showed no significant impact on the anastomosis establishment process or its effect.

14.
Opt Express ; 32(6): 10669-10678, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571272

RESUMO

Many applications involve the phenomenon of a material absorbing electromagnetic radiation. By exploiting wave interference, the efficiency of absorption can be significantly enhanced. Here, we propose Friedrich-Wintgen bound states in the continuum (F-W BICs) based on borophene metamaterials to realize coherent perfect absorption with a dual-band absorption peak in commercially important communication bands. Metamaterials consist of borophene gratings and a borophene sheet that can simultaneously support a Fabry-Perot plasmon resonance and a guided plasmon mode. The formation and dynamic modulation of the F-W BIC can be achieved by adjusting the width or carrier density of the borophene grating, while the strong coupling leads to the anti-crossover behavior of the absorption spectrum. Due to the weak angular dispersion originating from the intrinsic flat-band characteristic of the deep sub-wavelength periodic structure, the proposed plasmonic system exhibits almost no change in wavelength and absorption at large incident angles (within 70 degrees). In addition, we employ the temporal coupled-mode theory including near- and far-field coupling to obtain strong critical coupling, successfully achieve coherent perfect absorption, and can realize the absorption switch by changing the phase difference between the two coherent beams. Our findings can offer theoretical support for absorber design and all-optical tuning.

15.
Phys Rev Lett ; 132(13): 137201, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613259

RESUMO

Identifying hidden states in nonlinear physical systems that evade direct experimental detection is important as disturbances and noises can place the system in a hidden state with detrimental consequences. We study a cavity magnonic system whose main physics is photon and magnon Kerr effects. Sweeping a bifurcation parameter in numerical experiments (as would be done in actual experiments) leads to a hysteresis loop with two distinct stable steady states, but analytic calculation gives a third folded steady state "hidden" in the loop, which gives rise to the phenomenon of hidden multistability. We propose an experimentally feasible control method to drive the system into the folded hidden state. We demonstrate, through a ternary cavity magnonic system and a gene regulatory network, that such hidden multistability is in fact quite common. Our findings shed light on hidden dynamical states in nonlinear physical systems which are not directly observable but can present challenges and opportunities in applications.

17.
Nat Commun ; 15(1): 2249, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480695

RESUMO

Icing of seawater droplets is capable of causing catastrophic damage to vessels, buildings, and human life, yet it also holds great potential for enhancing applications such as droplet-based freeze desalination and anti-icing of sea sprays. While large-scale sea ice growth has been investigated for decades, the icing features of small salty droplets remain poorly understood. Here, we demonstrate that salty droplet icing is governed by salt rejection-accompanied ice crystal growth, resulting in freezing dynamics different from pure water. Aided by the observation of brine films emerging on top of frozen salty droplets, we propose a universal definition of freezing duration to quantify the icing rate of droplets having varying salt concentrations. Furthermore, we show that the morphology of frozen salty droplets is governed by ice crystals that sprout from the bottom of the brine film. These crystals grow until they pierce the free interface, which we term ice sprouting. We reveal that ice sprouting is controlled by condensation at the brine film free interface, a mechanism validated through molecular dynamics simulations. Our findings shed light on the distinct physics that govern salty droplet icing, knowledge that is essential for the development of related technologies.

18.
Nano Lett ; 24(12): 3801-3810, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38477714

RESUMO

The effectiveness of various cancer therapies for solid tumors is substantially limited by the highly hypoxic tumor microenvironment (TME). Here, a microalgae-integrated living hydrogel (ACG gel) is developed to concurrently enhance hypoxia-constrained tumor starvation therapy and immunotherapy. The ACG gel is formed in situ following intratumoral injection of a biohybrid fluid composed of alginate, Chlorella sorokiniana, and glucose oxidase, facilitated by the crossing-linking between divalent ions within tumors and alginate. The microalgae Chlorella sorokiniana embedded in ACG gel generate abundant oxygen through photosynthesis, enhancing glucose oxidase-catalyzed glucose consumption and shifting the TME from immunosuppressive to immunopermissive status, thus reducing the tumor cell energy supply and boosting antitumor immunity. In murine 4T1 tumor models, the ACG gel significantly suppresses tumor growth and effectively prevents postoperative tumor recurrence. This study, leveraging microalgae as natural oxygenerators, provides a versatile and universal strategy for the development of oxygen-dependent tumor therapies.


Assuntos
Chlorella , Microalgas , Neoplasias , Animais , Camundongos , Hidrogéis , Glucose Oxidase , Fotossíntese , Hipóxia , Oxigênio , Imunoterapia , Alginatos , Microambiente Tumoral
19.
Chem Commun (Camb) ; 60(28): 3814-3817, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488128

RESUMO

A novel and efficient regioselective annulation of phosphinyl allenes with 2-bromophenol or 1-bromo-2-naphthol is achieved by palladium catalysis. The divergent pathway delivers structurally diverse polyarylfurans and 2H-chromene skeletons via two different Heck-type annulations. This protocol represents regioselectivity-tunable transformation of allenes into functionalized O-containing heterocycles with excellent group compatibility.

20.
Environ Sci Technol ; 58(13): 5739-5749, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38456395

RESUMO

Epidemiological studies have demonstrated the embryonic and developmental toxicity of plasticizers. Thus, understanding the in utero biotransformation and accumulation of plasticizers is essential to assessing their fate and potential toxicity in early life. In the present study, 311 infant hair samples and 271 paired meconium samples were collected at birth in Guangzhou, China, to characterize fetal exposure to legacy and emerging plasticizers and their metabolites. Results showed that most of the target plasticizers were detected in infant hair, with medians of 9.30, 27.6, and 0.145 ng/g for phthalate esters (PAEs), organic phosphate ester (OPEs), and alternative plasticizers (APs), and 1.44, 0.313, and 0.066 ng/g for the metabolites of PAEs, OPEs, and APs, respectively. Positive correlations between plasticizers and their corresponding primary metabolites, as well as correlations among the oxidative metabolites of bis(2-ethylhexyl) phthalate (DEHP) and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), were observed, indicating that infant hair retained the major phase-I metabolism of the target plasticizers. While no positive correlations were found in parent compounds or their primary metabolites between paired infant hair and meconium, significant positive correlations were observed among secondary oxidative metabolites of DEHP and DINCH in hair and meconium, suggesting that the primary metabolites in meconium come from hydrolysis of plasticizers in the fetus but most of the oxidative metabolites come from maternal-fetal transmission. The parent compound/metabolite ratios in infant hair showed a decreasing trend across pregnancy, suggesting in utero accumulation and deposition of plasticizers. To the best of our knowledge, this study is the first to report in utero exposure to both parent compounds and metabolites of plasticizers by using paired infant hair and meconium as noninvasive biomonitoring matrices and provides novel insights into the fetal biotransformation and accumulation of plasticizers across pregnancy.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Gravidez , Recém-Nascido , Feminino , Plastificantes , Mecônio/metabolismo , Dietilexilftalato/metabolismo , Dietilexilftalato/toxicidade , Ácidos Ftálicos/metabolismo , Cabelo/metabolismo , Organofosfatos , Biotransformação , Ésteres/metabolismo , Exposição Ambiental/análise
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