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1.
J Environ Sci (China) ; 147: 165-178, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003037

RESUMO

In this study, two wheat-derived cadmium (Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions. Then, the impacts of the biochar (BC), M14+R27 (MR), and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing, heading, and mature stages of wheat plants under field-plot conditions. A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with the M14 or R27 treatment. The BC+MR treatment reduced the grain Cd content by 51.5%-67.7% and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75% in the rhizosphere soils compared with the BC or MR treatment. Compared with the BC or MR treatment, the relative abundances of the biomarkers associated with Gemmatimonas, Altererythrobacter, Gammaproteobacteria, Xanthomonadaceae, Phenylobacterium, and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents. In the BC+MR-treated root interior microbiome, the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor, while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor. Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes, leading to decreased wheat grain Cd uptake in the contaminated soil.


Assuntos
Cádmio , Carvão Vegetal , Microbiologia do Solo , Poluentes do Solo , Triticum , Triticum/metabolismo , Triticum/microbiologia , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Endófitos/fisiologia , Rizosfera , Solo/química , Biodegradação Ambiental , Microbiota/efeitos dos fármacos
2.
Adv Exp Med Biol ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38954247

RESUMO

According to the World Health Organization vector-borne diseases account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually. Vectors are organisms that are able to transmit infectious pathogens between humans, or from animals to humans. Many of these vectors are hematophagous insects, which ingest the pathogen from an infected host during a blood meal, and later transmit it into a new host. Malaria, dengue, African trypanosomiasis, yellow fever, leishmaniasis, Chagas disease, and many others are examples of diseases transmitted by insects.Both the diet and the infection with pathogens trigger changes in many metabolic pathways, including lipid metabolism, compared to other insects. Blood contains mostly proteins and is very poor in lipids and carbohydrates. Thus, hematophagous insects attempt to efficiently digest and absorb diet lipids and also rely on a large de novo lipid biosynthesis based on utilization of proteins and carbohydrates as carbon source. Blood meal triggers essential physiological processes as molting, excretion, and oogenesis; therefore, lipid metabolism and utilization of lipid storage should be finely synchronized and regulated regarding that, in order to provide the necessary energy source for these events. Also, pathogens have evolved mechanisms to hijack essential lipids from the insect host by interfering in the biosynthesis, catabolism, and transport of lipids, which pose challenges to reproduction, survival, fitness, and other insect traits.In this chapter, we have tried to collect and highlight the current knowledge and recent discoveries on the metabolism of lipids in insect vectors of diseases related to the hematophagous diet and pathogen infection.

3.
ChemMedChem ; : e202400472, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38957922

RESUMO

Therapeutic oligonucleotides, such as antisense DNA, show promise in treating previously untreatable diseases. However, their applications are still hindered by the poor membrane permeability of naked oligonucleotides. Therefore, it is necessary to develop efficient methods for intracellular oligonucleotide delivery. Previously, our group successfully developed disulfide-based Membrane Permeable Oligonucleotides (MPON), which achieved enhanced cellular uptake and gene silencing effects through an endocytosis-free uptake mechanism.  Herein, we report a new molecular design for the next generation of MPON, called trimer MPON. The trimer MPON consists of a tri-branched backbone, three α-lipoic acid units, and a spacer linker between the oligonucleotides and tri-branched cyclic disulfide unit. We describe the design, synthesis, and functional evaluation of the trimer MPON, offering new insights into the molecular design for efficient oligonucleotide delivery.

4.
Front Endocrinol (Lausanne) ; 15: 1398462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957441

RESUMO

Background: Cannabidiol (CBD), a non-psychoactive phytocannabinoid of cannabis, is therapeutically used as an analgesic, anti-convulsant, anti-inflammatory, and anti-psychotic drug. There is a growing concern about the adverse side effects posed by CBD usage. Pregnane X receptor (PXR) is a nuclear receptor activated by a variety of dietary steroids, pharmaceutical agents, and environmental chemicals. In addition to the role in xenobiotic metabolism, the atherogenic and dyslipidemic effects of PXR have been revealed in animal models. CBD has a low affinity for cannabinoid receptors, thus it is important to elucidate the molecular mechanisms by which CBD activates cellular signaling and to assess the possible adverse impacts of CBD on pro-atherosclerotic events in cardiovascular system, such as dyslipidemia. Objective: Our study aims to explore the cellular and molecular mechanisms by which exposure to CBD activates human PXR and increases the risk of dyslipidemia. Methods: Both human hepatic and intestinal cells were used to test if CBD was a PXR agonist via cell-based transfection assay. The key residues within PXR's ligand-binding pocket that CBD interacted with were investigated using computational docking study together with site-directed mutagenesis assay. The C57BL/6 wildtype mice were orally fed CBD in the presence of PXR antagonist resveratrol (RES) to determine how CBD exposure could change the plasma lipid profiles in a PXR-dependent manner. Human intestinal cells were treated with CBD and/or RES to estimate the functions of CBD in cholesterol uptake. Results: CBD was a selective agonist of PXR with higher activities on human PXR than rodents PXRs and promoted the dissociation of human PXR from nuclear co-repressors. The key amino acid residues Met246, Ser247, Phe251, Phe288, Trp299, and Tyr306 within PXR's ligand binding pocket were identified to be necessary for the agonistic effects of CBD. Exposure to CBD increased the circulating total cholesterol levels in mice which was partially caused by the induced expression levels of the key intestinal PXR-regulated lipogenic genes. Mechanistically, CBD induced the gene expression of key intestinal cholesterol transporters, which led to the increased cholesterol uptake by intestinal cells. Conclusion: CBD was identified as a selective PXR agonist. Exposure to CBD activated PXR signaling and increased the atherogenic cholesterol levels in plasma, which partially resulted from the ascended cholesterol uptake by intestinal cells. Our study provides potential evidence for the future risk assessment of CBD on cardiovascular disease, such as dyslipidemia.


Assuntos
Canabidiol , Colesterol , Camundongos Endogâmicos C57BL , Receptor de Pregnano X , Receptor de Pregnano X/metabolismo , Animais , Humanos , Camundongos , Canabidiol/farmacologia , Colesterol/metabolismo , Masculino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Simulação de Acoplamento Molecular
6.
BMC Sports Sci Med Rehabil ; 16(1): 151, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987830

RESUMO

BACKGROUND: Endurance athletes (EA) are an emerging population of focus for cardiovascular health. The oxygen uptake efficiency plateau (OUEP) is the levelling-off period of ratio between oxygen uptake (VO2) and ventilation (VE). In the cohort of EA, we externally validated prediction models for OUEP and derived with internal validation a new equation. METHODS: 140 EA underwent a medical assessment and maximal cycling cardiopulmonary exercise test. Participants were 55% male (N = 77, age = 21.4 ± 4.8 years, BMI = 22.6 ± 1.7 kg·m- 2, peak VO2 = 4.40 ± 0.64 L·min- 1) and 45% female (N = 63, age = 23.4 ± 4.3 years, BMI = 22.1 ± 1.6 kg·m- 2, peak VO2 = 3.21 ± 0.48 L·min- 1). OUEP was defined as the highest 90-second continuous value of the ratio between VO2 and VE. We used the multivariable stepwise linear regression to develop a new prediction equation for OUEP. RESULTS: OUEP was 44.2 ± 4.2 mL·L- 1 and 41.0 ± 4.8 mL·L- 1 for males and females, respectively. In external validation, OUEP was comparable to directly measured and did not differ significantly. The prediction error for males was - 0.42 mL·L- 1 (0.94%, p = 0.39), and for females was + 0.33 mL·L- 1 (0.81%, p = 0.59). The developed new prediction equation was: 61.37-0.12·height (in cm) + 5.08 (for males). The developed model outperformed the previous. However, the equation explained up to 12.9% of the variance (R = 0.377, R2 = 0.129, RMSE = 4.39 mL·L- 1). CONCLUSION: OUEP is a stable and transferable cardiorespiratory index. OUEP is minimally affected by fitness level and demographic factors. The predicted OUEP provided promising but limited accuracy among EA. The derived new model is tailored for EA. OUEP could be used to stratify the cardiorespiratory response to exercise and guide training.

7.
Front Endocrinol (Lausanne) ; 15: 1272886, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989003

RESUMO

Background: Obesity is associated with impaired glucose metabolism and hepatic insulin resistance. The aim was to investigate the associations of hepatic glucose uptake (HGU) and endogenous glucose production (EGP) to sedentary behavior (SB), physical activity (PA), cardiorespiratory fitness, dietary factors, and metabolic risk markers. Methods: Forty-four adults with metabolic syndrome (mean age 58 [SD 7] years, BMI ranging from 25-40kg/; 25 females) were included. HGU was measured by positron emission tomography during the hyperinsulinemic-euglycemic clamp. EGP was calculated by subtracting the glucose infusion rate during clamp from the glucose rate of disappearance. SB and PA were measured with hip-worn accelerometers (26 [SD3] days). Fitness was assessed by maximal bicycle ergometry with respiratory gas measurements and dietary intake of nutrients by 4-day food diaries. Results: HGU was not associated with fitness or any of the SB or PA measures. When adjusted for sex, age, and body fat-%, HGU was associated with whole-body insulin sensitivity (ß=0.58), water-insoluble dietary fiber (ß=0.29), energy percent (E%) of carbohydrates (ß=-0.32), saccharose (ß=-0.32), mono- and polyunsaturated fatty acids (ß=0.35, ß=0.41, respectively). EGP was associated with whole-body insulin sensitivity (ß=-0.53), and low-density lipoprotein cholesterol [ß=-0.31], and when further adjusted for accelerometry wear time, EGP was associated with standing [ß=-0.43]. (p-value for all< 0.05). Conclusions: Standing more, consuming a diet rich in fiber and unsaturated fatty acids, and a lower intake of carbohydrates, especially sugar, associate beneficially with hepatic insulin sensitivity. Habitual SB, PA, or fitness may not be the primary modulators of HGU and EGP. However, these associations need to be confirmed with intervention studies.


Assuntos
Fibras na Dieta , Ácidos Graxos Insaturados , Resistência à Insulina , Fígado , Síndrome Metabólica , Comportamento Sedentário , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Síndrome Metabólica/metabolismo , Fibras na Dieta/administração & dosagem , Fígado/metabolismo , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/administração & dosagem , Posição Ortostática , Exercício Físico , Idoso , Adulto , Técnica Clamp de Glucose , Aptidão Cardiorrespiratória/fisiologia
8.
Indian J Nucl Med ; 39(2): 77-82, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989309

RESUMO

Aim and Background: The aim of this study was to evaluate the prognostic value of imaging-based variables and tumor marker in predicting the progression-free survival (PFS) in treatment-naïve pancreatic cancer (PC) using baseline 18-fluorodeoxyglucose (18FDG) positron emission tomography/computed tomography (PET/CT). Materials and Methods: This retro-prospective study was conducted at PET/CT imaging facility of JCIA health-care facility of Pakistan. Total 68 patients with PCs were retrospectively included who had 18FDG PET/CT for staging from March 2017 to December 2020. Thirty-two patients had unresectable Stage IV disease on baseline imaging while the remaining 36 underwent Whipple's procedure and both categories were followed by chemotherapy with/without immunotherapy. These patients were followed for a median period of 18 months (1-62 months) for PFS. Logistic regression analysis and receiver operating characteristic (ROC) analysis were used for independent predictors of patients' demographics, tumor characteristics, CA 19-9, and maximum standardized uptake value (SUVmax) in PFS. Kaplan-Meier's survival curves were analyzed to measure PFS using ROC-derived significant cutoff values of CA 19-9 and SUVmax. Results: Median PFS was 18 months (11-45) with 60% (41/68) patients were either died or labelled having metabolic progressive disease (MPD. Using logistic regression analysis, significant correlations were found for Stage IV disease and pancreatic body/tail tumor with disease progression (odd ratio: 7.535 and 4.803, respectively; P < 0.05). Gender, obesity, histological tumor type, and 18FDG-avid regional nodes did not show a significant impact on PFS. On ROC analysis, SUVmax >5.3 of primary tumor and baseline CA 19-9 >197 U/ml were found to have a significant negative correlation with PFS (area under the curve: 0.827 and 0.911, respectively; P < 0.0001) and no association of age and primary tumor size in PFS. Significantly, shorter PFS was found using ROC-derived cutoff values of SUVmax >5.3 versus ≤5.3 of primary tumor (mean and 95% confidence interval [CI]: 16.7 vs. 48.5 and 10-23 vs. 41-56; log-rank = 25.014; P < 0.0001) and baseline CA 19-9 >197 versus ≤197 U/ml (mean and 95% CI: 11.8 vs. 46.9 and 7-16 vs. 39-55; log-rank = 38.217; P < 0.0001). Conclusion: SUVmax >5.3 of primary tumor and baseline CA 19-9 >197 U/ml were found to have a significant negative correlation with PFS in treatment-naïve PC patients. Among demographics, only Stage IV disease and pancreatic tail and body tumors were found to have a negative association with disease progression.

9.
Indian J Nucl Med ; 39(2): 139-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989303

RESUMO

Comprehension of the typical distribution pattern of 99mTc-methylenediphosphonate (MDP) is crucial for precise interpretation of bone scintigraphy. The presence of nonskeletal activity is predominantly confined to the kidneys and bladder, attributed to the standard renal excretion of 99mTc-MDP. We discuss a 70-year-old woman with a known case of brucellosis using rifampin, doxycycline, trimethoprim/sulfamethoxazole (co-trimoxazole), and ciprofloxacin for the past 8 months. Anterior and posterior aspects of the whole-body bone scan showed diffuse increased uptake in the bodies of L2 and L3 vertebrae and related intervertebral disks. However, unexpected uptake is noted in the right upper quadrant in the region of the gallbladder. Radiochemical impurities did not show during radiopharmaceutical (MDP) quality control, and the other patients showed normal distribution. This gallbladder uptake may be attributed to the altered distribution of the radiotracer and/or gallbladder injury caused by the administration of antibiotic therapy.

10.
Indian J Nucl Med ; 39(2): 106-114, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989317

RESUMO

Background: Positron emission tomography with computed tomography (PET-CT) using fluorine 18-fluorodeoxyglucose (F-18 FDG) is increasingly used to stage patients with locally advanced breast cancer and for assessing treatment response after neoadjuvant chemotherapy (NACT). Aims and Objectives: The aim of the study was to assess the correlation between PET-CT parameters and pathologic response of breast primary after NACT in breast cancer patients and to devise a grading system called NIMS grading system for response assessment using PET quantitative parameters. Materials and Methods: 55 patients who underwent F-18 FDG PET-CT before starting the therapy and again after completion of therapy were identified and included in the study. The clinical data and the histopathologic findings were recorded. All the patients received chemotherapy followed by surgery with axillary lymph node dissection. The PET-CT results were interpreted both qualitatively by visual analysis and quantitatively by estimating maximum Standardized uptake values(SUVmax) and other parameters - SUVmean, SUL, SUVBSA, Metabolic tumor volume (MTV) and Total lesion glycolysis (TLG). Results: The sensitivity and specificity of F-18 FDG PET-CT to detect the residual disease after neoadjuvant chemotherapy was 75.6% & 92.8% respectively. Differences between complete response and residual disease were significant for ΔSUVmax(p=0.005), ΔSUVmean(p=0.006), ΔSUL (0.005) and ΔSUVBSA(0.004), while ΔMTV and ΔTLG were not significantly different between the two groups. The new NIMS grading system included scoring of ΔSUVmax, ΔSUVBSA, ΔTLG and ΔMTV on scale of 1 to 4 and correlated well with PERCIST criteria. Conclusion: F-18 FDG PET-CT had a good accuracy in the detection of residual disease after completion of NACT. Pre chemotherapy PET-CT is not adequate to predict the response of primary tumour to chemotherapy. However, changes in the values of various PET-CT parameters are a sensitive tool to assess the response to chemotherapy. The new grading system is easy to use and showed good correlation to PERCIST.

11.
Indian J Nucl Med ; 39(2): 148-149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989320

RESUMO

Diffuse Tc-99m MIBI uptake in the lungs during parathyroid scintigraphy is exceptional, and only a few cases have described this unusual aspect. The differential diagnostic of this funding is a challenge when interpreting the examination, since it can be a sign of serious pathology. We report the case of unexpected diffusely increased Tc-99m MIBI uptake in bilateral lung fields in a patient with left cardiac dysfunction.

12.
Indian J Nucl Med ; 39(2): 150-152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989316

RESUMO

We present a case of a 22-year-old male patient who underwent a bone scan for evaluation of left condylar hyperplasia. Incidentally, the bone scan revealed bilateral thighs muscular uptake of technetium-99m methylene diphosphonate, which initially raised concerns for an underlying pathological process. However, further investigation revealed that the abnormal uptake was due to postexercise effects. This case report highlights the importance of considering benign causes of abnormal radiotracer uptake and the need for careful correlation with clinical history to avoid unnecessary diagnostic interventions.

13.
Curr Opin Chem Biol ; 81: 102499, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38996568

RESUMO

This review introduces the typical delivery process of messenger RNA (mRNA) nanomedicines and concludes that the delivery involves a at least four-step SCER cascade and that high efficiency at every step is critical to guarantee high overall therapeutic outcomes. This SCER cascade process includes selective organ-targeting delivery, cellular uptake, endosomal escape, and cytosolic mRNA release. Lipid nanoparticles (LNPs) have emerged as a state-of-the-art vehicle for in vivo mRNA delivery. The review emphasizes the importance of LNPs in achieving selective, efficient, and safe mRNA delivery. The discussion then extends to the technical and clinical considerations of LNPs, detailing the roles of individual components in the SCER cascade process, especially ionizable lipids and helper phospholipids. The review aims to provide an updated overview of LNP-based mRNA delivery, outlining recent innovations and addressing challenges while exploring future developments for clinical translation over the next decade.

14.
Int J Pharm ; : 124446, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38996825

RESUMO

The pharmaceutical industry has experienced a remarkable increase in the use of subcutaneous injection of monoclonal antibodies (mAbs), attributed mainly to its advantages in reducing healthcare-related costs and enhancing patient compliance. Despite this growth, there is a limited understanding of how tissue mechanics, physiological parameters, and different injection devices and techniques influence the transport and absorption of the drug. In this work, we propose a high-fidelity computational model to study drug transport and absorption during and after subcutaneous injection of mAbs. Our numerical model includes large-deformation mechanics, fluid flow, drug transport, and blood and lymphatic uptake. Through this computational framework, we analyze the tissue material responses, plume dynamics, and drug absorption. We analyze different devices, injection techniques, and physiological parameters such as BMI, flow rate, and injection depth. Finally, we compare our numerical results against the experimental data from the literature.

15.
BMC Public Health ; 24(1): 1825, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982434

RESUMO

BACKGROUND: Majority of new Human Immunodeficiency Virus (HIV)-positive persons in Ghana are aged 15-24. HIV prevalence among persons aged 15-24 years, a proxy for new infections, remained stable at 1.5% for 2017 and 2018, making it a significant public health concern. Yet only 26.4% of females and 8.6% of males aged 15-24 years know their HIV status. This study determined the predictive ability of the Health Belief Model (HBM) in HIV testing and counselling (HTC) uptake among youth (15-24 years) in the La-Nkwantanang Madina Municipality, Ghana. METHODS: A cross-sectional design was adopted for the study, using a multistage sampling method to select 415 youth aged 15-24. Data were collected using a structured interviewer-administered questionnaire, and analysed using binomial logistic regression with STATA software version 16.0 at p < 0.05 significance level and at 95% confidence interval. RESULTS: HTC uptake was 29.2%. Perceived susceptibility, perceived barriers, and perceived self-efficacy predicted HTC uptake. Youths with a high-risk perception for contracting HIV [OR = 3.03; 95% CI = 1.46, 6.30, p = 0.003], who perceived that they can contract HIV if not protected [OR = 3.69; 95% CI = 1.47, 9.22, p = 0.005], and worry about getting HIV [OR = 3.03, 95% CI = 1.61, 5.69, p < 0.001] (perceived susceptibility) were more likely to uptake HTC. Youths who had no trust issues with health workers [OR = 3.53; 95% CI = 1.46, 8.53, p = 0.005] and those who were not afraid of positive HIV test results [OR = 5.29; 95% CI = 2.66, 10.51, p,0.001] (perceived barriers) were more likely to uptake HTC. Youths who had no difficulties in turning up for appointments (perceived self-efficacy) had higher odds of HTC uptake [OR = 11.89, 95% CI = 6.73, 20.98, P < 0.001]. For the modifying factors, being married [OR = 2.96; 95% CI = 1.65-5.33], and having knowledge of HTC [OR = 9.10; 95% CI = 2.16-38.3], significantly influenced HTC uptake. CONCLUSION: Health promotion interventions to increase HTC uptake should focus on heightening the perception of susceptibility to HIV, reducing the barriers to HTC uptake, and increasing the self-efficacy for HTC uptake. The interventions should also target the significant modifying factors.


Assuntos
Aconselhamento , Infecções por HIV , Teste de HIV , Modelo de Crenças de Saúde , Humanos , Adolescente , Masculino , Feminino , Gana , Adulto Jovem , Estudos Transversais , Aconselhamento/estatística & dados numéricos , Teste de HIV/estatística & dados numéricos , Infecções por HIV/psicologia , Infecções por HIV/diagnóstico , Inquéritos e Questionários , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Conhecimentos, Atitudes e Prática em Saúde
16.
Artigo em Inglês | MEDLINE | ID: mdl-38995313

RESUMO

The atrazine nanodelivery system, composed of poly(ε-caprolactone) (PCL+ATZ) nanocapsules (NCs), has demonstrated efficient delivery of the active ingredient to target plants in previous studies, leading to greater herbicide effectiveness than conventional formulations. Established nanosystems can be enhanced or modified to generate new biological activity patterns. Therefore, this study aimed to evaluate the effect of chitosan coating of PCL+ATZ NCs on herbicidal activity and interaction mechanisms with Bidens pilosa plants. Chitosan-coated NCs (PCL/CS+ATZ) were synthesized and characterized for size, zeta potential, polydispersity, and encapsulation efficiency. Herbicidal efficiency was assessed in postemergence greenhouse trials, comparing the effects of PCL/CS+ATZ NCs (coated), PCL+ATZ NCs (uncoated), and conventional atrazine (ATZ) on photosystem II (PSII) activity and weed control. Using a hydroponic system, we evaluated the root absorption and shoot translocation of fluorescently labeled NCs. PCL/CS+ATZ presented a positive zeta potential (25 mV), a size of 200 nm, and an efficiency of atrazine encapsulation higher than 90%. The postemergent herbicidal activity assay showed an efficiency gain of PSII activity inhibition of up to 58% compared to ATZ and PCL+ATZ at 96 h postapplication. The evaluation of weed control 14 days after application ratified the positive effect of chitosan coating on herbicidal activity, as the application of PCL/CS+ATZ at 1000 g of a.i. ha-1 resulted in better control than ATZ at 2000 g of a.i. ha-1 and PCL+ATZ at 1000 g of a.i. ha-1. In the hydroponic experiment, chitosan-coated NCs labeled with a fluorescent probe accumulated in the root cortex, with a small quantity reaching the vascular cylinder and leaves up to 72 h after exposure. This behavior resulted in lower leaf atrazine levels and PSII inhibition than ATZ. In summary, chitosan coating of nanoatrazine improved the herbicidal activity against B. pilosa plants when applied to the leaves but negatively affected the root-to-shoot translocation of the herbicide. This study opens avenues for further investigations to improve and modify established nanosystems, paving the way for developing novel biological activity patterns.

17.
Chemistry ; : e202401719, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995511

RESUMO

Monocarboxylate transporter 8 (MCT8) is a trans-membrane transporter, which mediates the cellular delivery of thyroid hormones, L-thyroxine (T4) and 3,5,3 '-triiodo-L-thyronine (T3). In humans, the MCT8 protein is encoded by the SLC16A2 gene and mutations in the transporter cause a genetic neurological disorder known as Allan-Herndon-Dudley syndrome (AHDS). MCT8 deficiency leads to impaired transport of thyroid hormones in the brain. Radiolabelled T4 and T3 or LC/MS-MS methods have been used to monitor the thyroid hormone uptake through MCT8. Herein, we developed a fluorescent based assay to monitor the thyroid hormone uptake through MCT8. A dansyl-based fluorescent probe having L-thyroxine moiety is found to be highly selective towards MCT8 in living cells. The high selectivity of the probe towards MCT8 can be attributed to the halogen bond-mediated recognition by the transporter protein. The presence of a free carboxylic acid group is essential for the specificity of the probe towards MCT8. Additionally, the selectivity of the probe for MCT8 is abolished upon esterification of the carboxylic group. Similarly, MCT8 does not recognize the probe when it contains a free amine group.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38995610

RESUMO

Abiraterone acetate (ABA), a biopharmaceutical class IV drug suffers from solubility and permeability pitfalls resulting in limited oral bioavailability and positive food effect, i.e. multi-fold enhancement in drug absorption in the presence of food. This poses difficulties to physicians towards the estimation of dose and dosage regimen required for efficacious therapy of prostate cancer (PCa). Nanostructured lipid carriers (NLC) have demonstrated tremendous outcomes in enhancing the oral bioavailability of various entities along with food effect attenuation. In this study, Quality by design and multivariate analysis was employed for optimization of ABA loaded NLC (ABA NLC). The optimal size, PDI and zeta potential obtained using QbD were 134.6 nm, 0.163 and -15.7 mV respectively. Ex vivo qualitative and quantitative intestinal permeability studies demonstrated improved traversion of NLC through the intestinal segments. In vitro dissolution profile in biorelevant fast and fed gastric and intestinal media revealed minimal differences for ABA NLC compared to ABA. In vivo pharmacokinetics was performed to decipher the efficacy of ABA NLC in mitigating the food effect of ABA. The studies demonstrated 14.51-fold and 1.94-fold improvement in oral bioavailability during fasted and fed state respectively as compared to free ABA. The absorption mechanism of ABA NLC using chylomicron flow blocking approach conveyed lymphatic uptake as the major mechanism. Cmax fast/fed ratio was 0.9758 whereas, AUC fast/fed ratio was 0.9386, which being nearly equivalent, confirmed the food effect attenuation. Therefore, the results of the study demonstrate optimal pharmacokinetics of ABA NLC and its utility in circumventing the fast fed variability.

19.
Mol Imaging Radionucl Ther ; 33(2): 106-108, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38949459

RESUMO

Tc-99m methylene diphosphonate (MDP) is a bone imaging agent used for skeletal staging, but it can also be localized in extraosseous calcifying lesions. We report a case of an 84-year-old woman with breast carcinoma who underwent surgery followed by radiotherapy 10 years ago and now presented with a right axillary mass referred for Tc-99m MDP to exclude bone metastasis. Tc-99m MDP shows intense tracer uptake in the right thoracic region corresponding to the site of calcified soft tissue mass in the right lateral chest wall. Subsequent ultrasonography revealed an ill-defined lesion containing coarse calcifications. Biopsy showed radiation-induced sarcoma. Extra osseous Tc-99m MDP uptake may provide important diagnostic information that may alter patient management.

20.
Plant Physiol Biochem ; 214: 108886, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38950461

RESUMO

Methyl viologen (MV), also known as paraquat, is a widely used herbicide but has also been reported as highly toxic to different life forms. The mode of its operation is related to superoxide radical (O2.-) production and consequent oxidative damage. However, besides the damage to key macromolecules, reactive oxygen species (ROS; to which O2.- belongs) are also known as regulators of numerous ion transport systems located at cellular membranes. In this study, we used MV as a tool to probe the role of O2.- in regulating membrane-transport activity and systemic acquired tolerance in halophytic Chenopodium quinoa and glycophytic spinach plants. Both plant species showed growth reduction in terms of reduced shoot length, lower shoot fresh and dry weight, photosynthesis rate, and chlorophyll contents; however, quinoa showed less reduction in growth compared with spinach. This whole plant response was further examined by measuring the ion concentration, gene expression of ion transporters, activation of antioxidants, and osmolyte accumulation. We observed that at the mechanistic level, the differences in growth in response to MV were conferred by at least four complementary physiological mechanisms: (1) higher K+ loss from spinach leaves resulted from higher expression of MV-induced plasma membrane-based depolarization-activated K+ efflux GORK channel, (2) higher activation of high-affinity K+ uptake transporter HAK5 in quinoa, (3) higher antioxidant production and osmolyte accumulation in quinoa as compared with spinach, and (4) maintaining a higher rate of photosynthesis due to higher chlorophyll contents, and efficiency of photosystem II and reduced ROS and MDA contents. Obtained results also showed that MV induced O2.- significantly reduced N contents in both species but with more pronounced effects in glycophytic spinach. Taken together this study has shown the role of O2.- in regulating membrane ion transport and N metabolism in the leaves of halophyte vs. glycophyte in the context of oxidative stress tolerance.

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