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1.
Angiogenesis ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842751

RESUMO

Tissue-engineered skin substitutes (TESS) emerged as a new therapeutic option to improve skin transplantation. However, establishing an adequate and rapid vascularization in TESS is a critical factor for their clinical application and successful engraftment in patients. Therefore, several methods have been applied to improve the vascularization of skin substitutes including (i) modifying the structural and physicochemical properties of dermal scaffolds; (ii) activating biological scaffolds with growth factor-releasing systems or gene vectors; and (iii) developing prevascularized skin substitutes by loading scaffolds with capillary-forming cells. This review provides a detailed overview of the most recent and important developments in the vascularization strategies for skin substitutes. On the one hand, we present cell-based approaches using stem cells, microvascular fragments, adipose tissue derived stromal vascular fraction, endothelial cells derived from blood and skin as well as other pro-angiogenic stimulation methods. On the other hand, we discuss how distinct 3D bioprinting techniques and microfluidics, miRNA manipulation, cell sheet engineering and photosynthetic scaffolds like GelMA, can enhance skin vascularization for clinical applications. Finally, we summarize and discuss the challenges and prospects of the currently available vascularization techniques that may serve as a steppingstone to a mainstream application of skin tissue engineering.

2.
Calcif Tissue Int ; 114(6): 583-591, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642090

RESUMO

A pathological increase in intestinal leak is implicated in age-associated muscle loss, termed sarcopenia, and reduced sarcopenia-related quality-of-life (SarQoL). However, the potential therapies remain elusive. We investigated the effects of probiotic supplementation on sarcopenia and SarQoL in geriatric older adults. We randomized sarcopenic men into placebo (age = 71.4 ± 3.9 years, n = 63) and probiotic (age = 73 ± 4.1 years, n = 60) groups for 16 weeks. The probiotic used was one capsule daily of Vivomix 112 billion for 16 weeks. We measured sarcopenia parameters of handgrip strength (HGS) and skeletal mass index (SMI), plasma zonulin (marker of the intestinal leak), and SarQoL using a targeted questionnaire. Probiotics improved the SarQoL scores for locomotion, functionality, and activities of daily living and prevented a decline in cumulative SarQoL observed in the placebo group (all p < 0.05). Probiotic supplementation also reduced plasma zonulin and marker of systemic bacterial load. These changes were accompanied by an increase in HGS and maintenance of gait speed in the probiotic group compared to the placebo group. Correlation analysis revealed significant associations of cumulative SarQoL scores with plasma zonulin and HGS in the probiotic group. Collectively, probiotics improved SarQoL and HGS by repairing pathological intestinal leak. Future studies may further dissect the relation between intestinal leak and SarQoL in older adults taking probiotics.


Assuntos
Probióticos , Qualidade de Vida , Sarcopenia , Humanos , Probióticos/uso terapêutico , Probióticos/administração & dosagem , Idoso , Masculino , Suplementos Nutricionais , Força da Mão/fisiologia , Músculo Esquelético/efeitos dos fármacos , Atividades Cotidianas , Envelhecimento/fisiologia , Idoso de 80 Anos ou mais
3.
Nanotechnology ; 35(36)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38861966

RESUMO

Synergistic cancer therapies have attracted wide attention owing to their multi-mode tumor inhibition properties. Especially, photo-responsive photoimmunotherapy demonstrates an emerging cancer treatment paradigm that significantly improved treatment efficiency. Herein, near-infrared-II responsive ovalbumin functionalized Gold-Genipin nanosystem (Au-G-OVA NRs) was designed for immunotherapy and deep photothermal therapy of breast cancer. A facile synthesis method was employed to prepare the homogeneous Au nanorods (Au NRs) with good dispersion. The nanovaccine was developed further by the chemical cross-linking of Au-NRs, genipin and ovalbumin. The Au-G-OVA NRs outstanding aqueous solubility, and biocompatibility against normal and cancer cells. The designed NRs possessed enhanced localized surface plasmon resonance (LSPR) effect, which extended the NIR absorption in the second window, enabling promising photothermal properties. Moreover, genipin coating provided complimentary red fluorescent and prepared Au-G-OVA NRs showed significant intracellular encapsulation for efficient photoimmunotherapy outcomes. The designed nanosystem possessed deep photothermal therapy of breast cancer and 90% 4T1 cells were ablated by Au-G-OVA NRs (80µg ml-1concentration) after 1064 nm laser irradiation. In addition, Au-G-OVA NRs demonstrated outstanding vaccination phenomena by facilitating OVA delivery, antigen uptake, maturation of bone marrow dendritic cells, and cytokine IFN-γsecretion for tumor immunosurveillance. The aforementioned advantages permit the utilization of fluorescence imaging-guided photo-immunotherapy for cancers, demonstrating a straightforward approach for developing nanovaccines tailored to precise tumor treatment.


Assuntos
Ouro , Imunoterapia , Raios Infravermelhos , Iridoides , Nanotubos , Ovalbumina , Ouro/química , Iridoides/química , Iridoides/farmacologia , Animais , Ovalbumina/química , Ovalbumina/imunologia , Camundongos , Imunoterapia/métodos , Linhagem Celular Tumoral , Feminino , Nanotubos/química , Terapia Fototérmica/métodos , Fototerapia/métodos , Camundongos Endogâmicos BALB C , Humanos , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Células Dendríticas/imunologia , Ressonância de Plasmônio de Superfície
4.
J Chem Phys ; 160(3)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38230950

RESUMO

The semiconductor/insulator blends for organic field-effect transistors are a potential solution to improve the charge transport in the active layer by inducing phase separation in the blends. However, the technique is less investigated for long-chain conducting polymers such as Poly[2,5-(2-octyldodecyl)-3,6-diketopyrrolopyrrole-alt-5,5-(2,5-di(thien-2-yl)thieno [3,2-b]thiophene)] (DPPDTT), and lateral phase separation is generally reported due to the instability during solvent evaporation, which results in degraded device performance. Herein, we report how to tailor the dominant mechanism of phase separation in such blends and the molecular assembly of the polymer. For DPPDTT/PMMA blends, we found that for higher DPPDTT concentrations (more than 75%) where the vertical phase separation mechanism is dominant, PMMA assisted in the self-assembly of DPPDTT to form nanowires and micro-transport channels on top of PMMA. The formation of nanowires yielded 13 times higher mobility as compared to pristine devices. For blend ratios with DPPDTT ≤ 50%, both the competing mechanisms, vertical and lateral phase separation, are taking place. It resulted in somewhat lower charge carrier mobilities. Hence, our results show that by systematic tuning of the blend ratio, PMMA can act as an excellent binding material in long-chain polymers such as DPPDTT and produce vertically stratified and aligned structures to ensure high mobility devices.

5.
J Nanobiotechnology ; 22(1): 92, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443940

RESUMO

BACKGROUND: Gold nanoparticles (GNPs) have been extensively recognized as an active candidate for a large variety of biomedical applications. However, the clinical conversion of specific types of GNPs has been hindered due to their potential liver toxicity. The origin of their hepatotoxicity and the underlying key factors are still ambiguous. Because the size, shape, and surfactant of GNPs all affect their properties and cytotoxicity. An effective and sensitive platform that can provide deep insights into the cause of GNPs' hepatotoxicity in vitro is therefore highly desired. METHODS: Here, hepatocyte organoid models (Hep-orgs) were constructed to evaluate the shape-dependent hepatotoxicity of GNPs. Two types of GNPs with different nanomorphology, gold nanospheres (GNSs) and spiny gold nanobranches (GNBs), were synthesized as the representative samples. Their shape-dependent effects on mice Hep-orgs' morphology, cellular cytoskeletal structure, mitochondrial structure, oxidative stress, and metabolism were carefully investigated. RESULTS: The results showed that GNBs with higher spikiness and tip curvature exhibited more significant cytotoxicity compared to the rounded GNSs. The spike structure of GNBs leads to a mitochondrial damage, oxidative stress, and metabolic disorder in Hep-orgs. Meanwhile, similar trends can be observed in HepG2 cells and mice models, demonstrating the reliability of the Hep-orgs. CONCLUSIONS: Hep-orgs can serve as an effective platform for exploring the interactions between GNPs and liver cells in a 3D perspective, filling the gap between 2D cell models and animal models. This work further revealed that organoids can be used as an indispensable tool to rapidly screen and explore the toxic mechanism of nanomaterials before considering their biomedical functionalities.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nanopartículas Metálicas , Animais , Camundongos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Reprodutibilidade dos Testes , Modelos Animais de Doenças , Hepatócitos , Organoides
6.
Public Health ; 231: 187-197, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703493

RESUMO

OBJECTIVES: Cardiovascular diseases (CVDs) and neoplasms have been considered as public health concerns worldwide. This study aimed to estimate the epidemiological patterns of death burden on CVDs and neoplasms and its attributable risk factors in Western Europe from 1990 to 2019 to discuss the potential causes of the disparities. STUDY DESIGN AND METHODS: We collected data on CVDs and neoplasms deaths in 24 Western European countries from the Global Burden of Disease Study. We analyzed patterns by age, sex, country, and associated risk factors. The results include percentages of total deaths, age-standardized death rates per 100,000 population, and uncertainty intervals (UIs). Time trends were assessed using annual percent change. RESULTS: In 2019, CVDs and neoplasms accounted for 33.54% and 30.15% of Western Europe's total deaths, with age-standardized death rates of 128.05 (95% UI: 135.37, 113.02) and 137.51 (95% UI: 142.54, 128.01) per 100,000. Over 1990-2019, CVDs rates decreased by 54.97%, and neoplasms rates decreased by 19.54%. Top CVDs subtypes were ischemic heart disease and stroke; top cancers for neoplasms were lung and colorectal. Highest CVD death burdens were in Finland, Greece, Austria; neoplasm burdens in Monaco, San Marino, Andorra. The major risk factors were metabolic (CVDs) and behavioral (neoplasms). Gender differences revealed higher CVDs death burden in males, while neoplasms burden varied by risk factors and age groups. CONCLUSION: In 2019, CVDs and neoplasms posed significant health risks in Western Europe, with variations in death burdens and risk factors across genders, age groups, and countries. Future interventions should target vulnerable groups to lessen the impact of CVDs and neoplasms in the region.


Assuntos
Doenças Cardiovasculares , Neoplasias , Humanos , Europa (Continente)/epidemiologia , Neoplasias/mortalidade , Neoplasias/epidemiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Fatores de Risco , Idoso de 80 Anos ou mais , Adulto Jovem , Adolescente , Causas de Morte , Carga Global da Doença
7.
Int J Mol Sci ; 25(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38891999

RESUMO

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant disorder characterized by multiple juvenile polyps in the gastrointestinal tract, often associated with mutations in genes such as Smad4 and BMPR1A. This study explores the impact of Smad4 knock-out on the development of intestinal polyps using collaborative cross (CC) mice, a genetically diverse model. Our results reveal a significant increase in intestinal polyps in Smad4 knock-out mice across the entire population, emphasizing the broad influence of Smad4 on polyposis. Sex-specific analyses demonstrate higher polyp counts in knock-out males and females compared to their WT counterparts, with distinct correlation patterns. Line-specific effects highlight the nuanced response to Smad4 knock-out, underscoring the importance of genetic variability. Multimorbidity heat maps offer insights into complex relationships between polyp counts, locations, and sizes. Heritability analysis reveals a significant genetic basis for polyp counts and sizes, while machine learning models, including k-nearest neighbors and linear regression, identify key predictors, enhancing our understanding of juvenile polyposis genetics. Overall, this study provides new information on understanding the intricate genetic interplay in the context of Smad4 knock-out, offering valuable insights that could inform the identification of potential therapeutic targets for juvenile polyposis and related diseases.


Assuntos
Modelos Animais de Doenças , Polipose Intestinal , Síndromes Neoplásicas Hereditárias , Proteína Smad4 , Animais , Feminino , Masculino , Camundongos , Camundongos de Cruzamento Colaborativo/genética , Patrimônio Genético , Polipose Intestinal/genética , Polipose Intestinal/congênito , Polipose Intestinal/patologia , Pólipos Intestinais/genética , Pólipos Intestinais/patologia , Camundongos Knockout , Síndromes Neoplásicas Hereditárias/genética , Proteína Smad4/genética
8.
Arch Med Res ; 55(5): 103025, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38879906

RESUMO

PURPOSE: Sarcopenia or age-associated muscle loss is common in patients with Alzheimer's disease (AD). We have previously demonstrated the contribution of a leaky gut to sarcopenia in AD. Here, we asked whether resistant exercise (RE) reduces the sarcopenia phenotype by repairing intestinal leakage in patients with AD. METHOD: A prospective, single-center study of older adults, including healthy controls and patients with AD (n = 44-51/group), was conducted to measure plasma zonulin and claudin-3 (markers of intestinal leakage), handgrip strength (HGS), and short physical performance battery (SPPB) as a measure of functional capacity. Measurements in patients with AD were performed at baseline and after 12 weeks of RE. RESULTS: At baseline, patients with AD had higher plasma zonulin and claudin-3 and lower HGS, gait speed, and SPPB scores than controls. RE reduced plasma zonulin and claudin-3 levels and improved HGS, SPPB scores, and gait speed. Regression analysis revealed robust relationships between changes in plasma zonulin and claudin-3 with HGS. Plasma zonulin was also positively associated with SPPB scores. In addition, RE downregulated plasma markers of inflammation and oxidative stress. However, the prevalence of sarcopenia based on low HGS and muscle atrophy or low SPPB was not affected by RE. CONCLUSION: Taken together, disruption of the intestinal mucosal barrier may contribute to functional decline and sarcopenia in AD, which is incompletely recovered by RE. Circulating levels of zonulin and claudin-3 may be valuable in predicting sarcopenia and functional capacity in older adults with AD.


Assuntos
Doença de Alzheimer , Claudina-3 , Força da Mão , Haptoglobinas , Treinamento Resistido , Sarcopenia , Humanos , Sarcopenia/etiologia , Sarcopenia/fisiopatologia , Sarcopenia/prevenção & controle , Sarcopenia/sangue , Masculino , Feminino , Idoso , Estudos Prospectivos , Doença de Alzheimer/sangue , Doença de Alzheimer/fisiopatologia , Haptoglobinas/metabolismo , Claudina-3/sangue , Precursores de Proteínas/sangue , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Biomarcadores/sangue
9.
R Soc Open Sci ; 11(5): 240153, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39076796

RESUMO

With the wide potential of organic field-effect transistors in all the modern electronic circuitries, researchers are grappling with the challenge of poor charge transport and hence lower mobility in organic polymers. Low-charge carrier mobility is mainly due to disorder in the molecular packing of organic semiconductors along with other factors, such as impurities, defects and interactions between molecules. The current research work has been conducted to align the molecular chains of poly[4-(4,4-dihexadecyl-4H-cyclopenta[1,2-|||b:5,4-|b']|dithiophen-2-yl)-alt-[1,2,5]thiadiazolo-[3,4-c]pyridine] (PCDTPT) using directional coating techniques such as dip coating and brush coating on nano-grooved substrates. Long-range order of polymer chains was clearly observed along the direction of brush coating and nanogrooves in optical and atomic force microscope (AFM) images while transmission spectra confirmed decreased pi-pi stacking for the polymer films deposited by this technique. By comparing the mobility performance of brush-coated devices with other techniques, we found a remarkable mobility enhancement of 90 times that of conventional spin-coated device and 24 times enhancement compared with the dip-coated device for the case when the alignment of polymer chains was parallel to the channel. All the fabrication and characterizations were performed in the ambient environment. This study demonstrates a potential approach to align the polymers on long and short ranges hence providing a route for high-performing devices in ambient conditions.

10.
Mol Diagn Ther ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961032

RESUMO

OBJECTIVES: Plasma C-terminal agrin-fragment-22 (CAF22), a breakdown product of neuromuscular junction, is a potential biomarker of muscle loss. However, its levels from adolescence to octogenarians are unknown. METHODS: We evaluated young (18-34 years, n = 203), middle-aged (35-59 years, n = 163), and old men (60-87 years, n = 143) for CAF22, handgrip strength (HGS), appendicular skeletal-mass index (ASMI), and gait speed. RESULTS: We found an age-associated increase in CAF22 from young (100.9 ± 29 pmol) to middle-aged (128.3 ± 38.7 pmol) and older men (171.5 ± 35.5 pmol) (all p<0.05). This was accompanied by a gradual reduction in HGS (37.7 ± 6.1 kg, 30.2 ± 5.2 kg, and 26.6 ± 4.7 kg, for young, middle-aged, and old men, respectively), ASMI (8.02 ± 1.02 kg/m2, 7.65 ± 0.92 kg/m2, 6.87 ± 0.93 kg/m2, for young, middle-aged, and old men, respectively), and gait speed (1.29 ± 0.24 m/s, 1.05 ± 0.16 m/s, and 0.81 ± 0.13 m/s, for young, middle-aged, and old men, respectively). After adjustment for age, we found negative regressions of CAF22 with HGS (- 0.0574, p < 0.001) and gait speed (- 0.0162, p < 0.001) in the cumulative cohort. The receiver operating characteristics analysis revealed significant efficacy of plasma CAF22 in diagnosing muscle weakness (HGS < 27 kg) (middle-aged men; AUC = 0.731, 95% CI = 0.629-0.831, p < 0.001, Older men; AUC = 0.816, 95% CI = 0.761-0.833, p < 0.001), and low gait speed (0.8 m/s) (middle-aged men; AUC = 0.737, 95% CI = 0.602-0.871, p < 0.001, older men; AUC = 0.829, 95% CI = 0.772-0.886, p < 0.001), and a modest efficacy in diagnosing sarcopenia (middle-aged men; AUC = 0.701, 95% CI = 0.536-0.865, p = 0.032, older men; AUC = 0.822, 95% CI = 0.759-0.884, p < 0.001) in middle-aged and older men. CONCLUSION: Altogether, CAF22 increases with advancing age and may be a reliable marker of muscle weakness and low gait speed.

11.
Arch Med Res ; 55(4): 102998, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615625

RESUMO

OBJECTIVES: Metformin protects against age-related muscle decline, termed sarcopenia. However, the effects on sarcopenia quality-of-life (SarQoL) are unknown. We investigated the effects of metformin on SarQoL and associated mechanisms in older adults. METHOD: This double-blind randomized, placebo-controlled trial included geriatric adult men, divided into non-sarcopenic controls (age = 72.2 ± 4.3 years, n = 52) and two groups of patients with sarcopenia randomized into placebo (age at baseline = 74.4 ± 5.7 years, n = 54) and metformin (age at baseline = 71.2 ± 3.9 years, n = 47) groups. Patients in the metformin group received 1.7 grams twice daily for four months. We evaluated SarQoL, handgrip strength (HGS), plasma zonulin, c-reactive protein (CRP), and 8-isoprostanes. RESULTS: Patients with sarcopenia had lower HGS and SarQoL than controls (both p <0.05). Metformin improved the HGS and the SarQoL domains related to physical and mental health, locomotion, and leisure activities, as well as cumulative SarQoL scores (all p <0.05). Metformin also prevented the decline in the SarQoL domains for functionality and fear. Among plasma biomarkers, metformin reduced the levels of zonulin, CRP, 8-isoprostanes, and creatine kinase. We also found a significant correlation of plasma zonulin with cumulative SarQoL in patients with sarcopenia taking metformin, suggesting a role for intestinal repair in improving SarQoL. Finally, metformin did not affect body composition and gait speed. CONCLUSION: Overall, metformin improved HGS and SarQoL by repairing intestinal leakage. Our data have clinical relevance for improving the quality of life in older adults with sarcopenia.


Assuntos
Força da Mão , Metformina , Qualidade de Vida , Sarcopenia , Humanos , Metformina/uso terapêutico , Metformina/administração & dosagem , Sarcopenia/tratamento farmacológico , Idoso , Masculino , Método Duplo-Cego , Haptoglobinas/metabolismo , Proteína C-Reativa/metabolismo , Precursores de Proteínas/sangue , Idoso de 80 Anos ou mais
12.
RSC Adv ; 14(25): 17877-17887, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38836171

RESUMO

The precise manipulation of electromagnetic and thermoelectric characteristics in the miniaturization of electronic devices offers a promising foundation for practical applications in quantum computing. Double perovskites characterized by stability, non-toxicity, and spin polarization, have emerged as appealing candidates for spintronic applications. This study explores the theoretical elucidation of the influence of iridium's 5d electrons on the magnetic characteristics of Sr2AIrO6 (A = Y, Lu, Sc) with WIEN2k code. The determined formation energies confirm the thermodynamic stability while an analysis of band structure and the density of states (DOS) reveals a half-metallic ferromagnetic character. This characteristic is comprehensible through the analysis of exchange constants and exchange energies. The current analysis suggests that crystal field effects, a fundamental hybridization process and exchange energies contribute to the emergence of ferromagnetism due to electron-spin interactions. Finally, assessments of electrical and thermal conductivities, Seebeck coefficient, power factor, figure of merit and magnetic susceptibility are conducted to assess the potential of the investigated materials for the applications in thermoelectric devices.

13.
Adv Healthc Mater ; : e2401197, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39132863

RESUMO

Triple-negative breast cancer (TNBC) is the most common primary tumor of the breast with limited effectual drug availability. Therefore, the aim of the study is to develop an innovative phyto-nanomedicine (PNM) to cure TNBC with the least genotoxicity. Hereinafter, the sea buckthorn' extracted polyphenols (SBP), combine with metformin (MET), are synthesized as a novel PNM to evaluate its anti-tumor properties, effectiveness, and mechanism of action in TNBC in vitro and in vivo models. The SBP exhibits 16 new kinds of polyphenols that are been reported earlier which regulated cell development, proliferation, and programmed cell death (PCD) effectively. SBP-MET PNM inhibits MDA-MB-231 (47%), MDA-MB-436 (46%), and 4T1 (46%) cell proliferation but does not affect L929 normal murine cell development and successfully induce PCD (73.19%) in MDA-MB-231 cells. Mechanistically, in vivo SBP-MET proteome expression profiling reveals upregulation of proapoptotic Bax protein and activation of Fas signaling pathways convince downstream Daxx and FADD proteins, which further triggers Caspase-3 that prompts apoptosis in human TNBC cells by cleaving PARP-1 protein. Current findings establish innovative highly biocompatible phyto-nanomedicine that has significant potential to inhibit TNBC cell growth and induce regulated cell death (RCD) in vivo model, thereby opening a new arena for TNBC therapy.

14.
J Biomater Sci Polym Ed ; : 1-21, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155278

RESUMO

Bacterial infections present a major global challenge. Penicillin, a widely used antibiotic known for its effectiveness and safety, is frequently prescribed. However, its short half-life necessitates multiple high-dose daily administrations, leading to severe side-effects. Therefore, this study aims to address these issues by developing hydrogels which control the release of penicillin and alleviate its adverse effects. Various combinations of aspartic acid and acrylamide were crosslinked by N', N'-methylene bisacrylamide through a free radical polymerization process to prepare aspartic acid/acrylamide (Asp/Am) hydrogels. The fabricated hydrogels underwent comprehensive characterization to assess physical properties and thermal stability. The soluble and insoluble fractions and porosity of the synthesized matrix were evaluated by sol-gel and porosity studies. Gel fraction was estimated at 88-96%, whereas sol fraction was found 12-4% and porosity found within the 63-78% range for fabricated hydrogel formulations. Maximum swelling and drug release were seen at pH 7.4, demonstrating a controlled drug release from hydrogel networks. The results showed that swelling, porosity, gel fraction, and drug release increased with higher concentrations of aspartic acid and acrylamide. However, integration of N', N'-methylene bisacrylamide exhibited the opposite effect on swelling and porosity, while increasing gel fraction. All formulations followed the Korsymer-Peppas model of kinetics with 'r' values within the range of 0.9740-0.9980. Furthermore, the cytotoxicity study indicated an effective and safe use of hydrogel because the cell viability was higher than 70%. Therefore, these prepared hydrogels show promise candidates for controlled release of Penicillin and are anticipated to be valuable in clinical applications.

15.
Transplant Proc ; 56(3): 557-560, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508914

RESUMO

BACKGROUND: Vitamin D is the main hormone that plays a critical role in controlling mineral homeostasis. Transplant recipients frequently have altered levels of 25-hydroxyvitamin D (25[OH] D) and 1, 25-hydroxyvitamin (1, 25[OH] D). OBJECTIVES: To explore the status of vitamin D level in renal allograft recipients and its association with renal function and cardio-metabolic risk markers. METHODS: One hundred two adult kidney transplant recipients (KTRs) were included. Clinical history and information about transplantation and immunosuppression were recorded. Blood and urine samples were collected for relevant laboratory tests, including chronic kidney disease (CKD)-mineral and bone disorder markers (Ca, PO4, and 25[OH] D). RESULTS: The mean age was 35 ± 8 years, with a male/female ratio of 89/11%. The transplant duration was 34 ± 26 (4.5-112) months. All donors involved were living-related: fathers comprised 44%, wives 16%, sisters 13%, mothers 11%, and the others 16% (ie, brothers, sons, daughters, uncles, aunts). The immunosuppression regimen included prednisolone and tacrolimus in all, with mycophenolate mofetil in 96%. The estimated glomerular filtration rate showed CKD distribution from stage 1 to 5 in 6%, 29%, 44%, 15%, and 6%, respectively. Vitamin D level was lower in 22% (<20 ng/mL), insufficient (20-30 ng/mL) in 48%, and adequate (>30 ng/mL) in 30%. We compared different clinical and laboratory variables in 3 different vitamin D groups but found no difference in cardio-renal risk factors (P = Not Significant). Similarly, no correlation was seen between vitamin D levels and other clinical and metabolic factors. CONCLUSION: According to conventional cutoffs, the vitamin D (25[OH] D) level is inadequate in 70% of renal allograft recipients. The hormone level has no apparent association with renal function and major cardio-metabolic risk factors.


Assuntos
Biomarcadores , Transplante de Rim , Vitamina D , Vitamina D/análogos & derivados , Humanos , Transplante de Rim/efeitos adversos , Vitamina D/sangue , Feminino , Masculino , Adulto , Biomarcadores/sangue , Fatores de Risco , Transplantados , Taxa de Filtração Glomerular , Pessoa de Meia-Idade , Rim/fisiopatologia , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos
16.
Colloids Surf B Biointerfaces ; 237: 113834, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479259

RESUMO

Precise diagnosis of complex and soft tumors is challenging, which limits appropriate treatment options to achieve desired therapeutic outcomes. However, multifunctional nano-sized contrast enhancement agents based on nanoparticles improve the diagnosis accuracy of various diseases such as cancer. Herein, a facile manganese-hafnium nanocomposites (Mn3O4-HfO2 NCs) system was designed for bimodal magnetic resonance imaging (MRI)/computed tomography (CT) contrast enhancement with a complimentary function of photodynamic therapy. The solvothermal method was used to fabricate NCs, and the average size of Mn3O4 NPs and Mn3O4-HfO2 NCs was about 7 nm and 15 nm, respectively, as estimated by TEM. Dynamic light scattering results showed good dispersion and high negative (-33 eV) zeta potential, indicating excellent stability in an aqueous medium. Mn3O4-HfO2 NCs revealed negligible toxic effects on the NCTC clone 929 (L929) and mouse colon cancer cell line (CT26), demonstrating promising biocompatibility. The synthesized Mn3O4-HfO2 NCs exhibit significant enhancement in T1-weighted magnetic resonance imaging (MRI) and X-ray computed tomography (CT), indicating the appropriateness for dual-modal MRI/CT molecular imaging probes. Moreover, ultra-small Mn3O4-HfO2 NCs show good relaxivities for MRI/CT. These nanoprobes Mn3O4-HfO2 NCs further possessed outstanding reactive oxygen species (ROS) generation ability under minute ultraviolet light (6 mW·cm-2) to ablate the colon cancer cells in vitro. Therefore, the designed multifunctional Mn3O4-HfO2 NCs were ideal candidates for cancer diagnosis and photodynamic therapy.


Assuntos
Neoplasias do Colo , Nanocompostos , Nanopartículas , Fotoquimioterapia , Camundongos , Animais , Manganês , Háfnio , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico
17.
J S Afr Vet Assoc ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38533817

RESUMO

Reactive oxygen species at supra-physiological levels trigger oxidative stress during cryopreservation, which can be neutralised by incorporating suitable antioxidants into the semen extender medium. This study was intended to explore the effect of asiatic acid (AA) as an antioxidant in semen extender on frozen-thawed sperm quality and in vivo fertility of bull sperm. Semen was collected from Holstein Friesian bulls for 10 consecutive weeks (total ejaculates = 60). Semen was cryopreserved with a Tris citric acid egg yolk-based extender supplemented with 0 (control), 20, 40, 60, and 100 µM AA. The supplementation of the extender with 40 and 60 µM AA improved (p < 0.05) post-thaw motility kinematics, plasma membrane integrity, acrosome integrity, sperm viability, and DNA integrity of bull sperm. Mitochondrial membrane potential was high (p < 0.05) with 60 µM of AA concentration in extender media. The catalase activity in seminal plasma was maintained (p < 0.05) when semen was added with 20, 40, and 60 µM of AA. The in vivo fertility was found to be significantly high with the semen extended with 60 µM AA. Conclusively, this study showed that AA supplementation in semen extender significantly improved sperm motility kinematics and cell integrity, conserved antioxidant enzyme activity, and improved in vivo fertility.

18.
Acta Biomater ; 177: 431-443, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38307478

RESUMO

The noble metal NPs that are currently applied to photothermal therapy (PTT) have their photoexcitation location mainly in the NIR-I range, and the low tissue penetration limits their therapeutic effect. The complexity of the tumor microenvironment (TME) makes it difficult to inhibit tumor growth completely with a single therapy. Although TME has a high level of H2O2, the intratumor H2O2 content is still insufficient to catalyze the generation of sufficient hydroxide radicals (‧OH) to achieve satisfactory therapeutic effects. The AuPd-GOx-HA (APGH) was obtained from AuPd bimetallic nanodumbbells modified by glucose oxidase (GOx) and hyaluronic acid (HA) for photothermal enhancement of tumor starvation and cascade catalytic therapy in the NIR-II region. The CAT-like activity of AuPd alleviates tumor hypoxia by catalyzing the decomposition of H2O2 into O2. The GOx-mediated intratumoral glucose oxidation on the one hand can block the supply of energy and nutrients essential for tumor growth, leading to tumor starvation. On the other hand, the generated H2O2 can continuously supply local O2, which also exacerbates glucose depletion. The peroxidase-like activity of bimetallic AuPd can catalyze the production of toxic ‧OH radicals from H2O2, enabling cascade catalytic therapy. In addition, the high photothermal conversion efficiency (η = 50.7 %) of APGH nanosystems offers the possibility of photothermal imaging-guided photothermal therapy. The results of cell and animal experiments verified that APGH has good biosafety, tumor targeting, and anticancer effects, and is a precious metal nanotherapeutic system integrating glucose starvation therapy, nano enzyme cascade catalytic therapy, and PTT therapy. This study provides a strategy for photothermal-cascade catalytic synergistic therapy combining both exogenous and endogenous processes. STATEMENT OF SIGNIFICANCE: AuPd-GOx-HA cascade nanoenzymes were prepared as a potent cascade catalytic therapeutic agent, which enhanced glucose depletion, exacerbated tumor starvation and promoted cancer cell apoptosis by increasing ROS production through APGH-like POD activity. The designed system has promising photothermal conversion ability in the NIR-II region, simultaneously realizing photothermal-enhanced catalysis, PTT, and catalysis/PTT synergistic therapy both in vitro and in vivo. The present work provides an approach for designing and developing catalytic-photothermal therapies based on bimetallic nanoenzymatic cascades.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Animais , Terapia Fototérmica , Catálise , Glucose , Glucose Oxidase , Neoplasias/terapia , Linhagem Celular Tumoral , Microambiente Tumoral
19.
ACS Biomater Sci Eng ; 10(8): 5068-5079, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38940279

RESUMO

External factors often lead to predictable damage, such as chemical injuries, burns, incisions, and wounds. Bacterial resistance to antibiotics at wound sites underscores the importance of developing hydrogel composite systems with inorganic nanoparticles possessing antibacterial properties to treat infected wounds and expedite the skin regeneration process. In this study, a promising TiO2-HAp@PF-127@CBM inorganic and organic integrated hydrogel system was designed to address challenges associated with bacterial resistance and wound healing. The synthesized TiO2-hydroxyapatite (HAp) nanocomposites were coated with an FDA-approved PluronicF-127 polymer and combined with a carbomer hydrogel (CBM) to accomplish the final product. The synthesized nanoparticles exhibit enhanced biocompatibility against L929 and HUVECs and cell proliferation effects. To mitigate oxidative stress caused by TiO2-induced reactive oxygen species in dark environments for effective antibacterial effects, HAp promotes cell proliferation, expediting wound skin layer formation. CBM binds to inorganic nanoparticles, facilitating their gradual release and promoting wound healing. The reduced inflammation and enhanced tissue regeneration observed in the TiO2-HAp@PF-127@CBM group suggest a favorable environment for wound repair. These results align with prior findings highlighting the biocompatibility and wound-healing properties of titanium-HAp-based materials. The ability of the TiO2-HAp@PF-127@CBM hydrogel dressing to promote granulation tissue formation and facilitate epidermal regeneration underscores its potential for promoting antibacterial effects and wound healing applications.


Assuntos
Antibacterianos , Durapatita , Hidrogéis , Nanocompostos , Titânio , Cicatrização , Titânio/química , Titânio/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Hidrogéis/farmacologia , Durapatita/química , Durapatita/farmacologia , Nanocompostos/química , Nanocompostos/uso terapêutico , Humanos , Camundongos , Animais , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular , Escherichia coli/efeitos dos fármacos
20.
J Control Release ; 373: 547-563, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39059501

RESUMO

Melanoma, known for its aggressive metastatic nature, presents a formidable challenge in cancer treatment, where conventional therapies often fall short. This study introduces a pioneering approach utilizing metal-free nanosystem as tumor vaccines, spotlighting their potential in revolutionizing melanoma treatment. This work employed organic nitroxides, specifically 4-carboxy-TEMPO, in combination with chitosan (CS), to create a novel nanocomposite material - the CS-TEMPO-OVA nanovaccines. This composition not only improves biocompatibility and extends blood circulation time of TEMPO but also marks a significant departure from traditional gadolinium-based contrast agents in MRI technology, addressing safety concerns. CS-TEMPO-OVA nanovaccines demonstrate excellent biocompatibility at both the cellular and organoid level. They effectively stimulate bone marrow-derived dendritic cells (BMDCs), which in turn promote the maturation and activation of T cells. This ultimately leads to a strong production of essential cytokines. These nanovaccines serve a dual purpose as both therapeutic and preventive. By inducing an immune response, activating cytotoxic T cells, and promoting macrophage M1 polarization, they effectively inhibit melanoma growth and enhance survival in mouse models. When combined with αPD-1, the CS-TEMPO-OVA nanovaccines significantly bolster the infiltration of cytotoxic T lymphocytes (CTLs) within tumors, sparking a powerful systemic antitumor response that effectively curbs tumor metastasis. The ability of these nanovaccines to control both primary (subcutaneous) and metastatic B16-OVA tumors highlights their remarkable efficacy. Furthermore, the CS-TEMPO-OVA nanovaccine can be administered in vivo via both intravenous and intramuscular routes, both of which effectively enhance the T1 contrast of magnetic resonance imaging in tumor tissue. This study offers invaluable insights into the integrated application of these nanovaccines in both clinical diagnostics and treatment, marking a significant stride in cancer research and patient care.

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