1,646 research outputs found
Spectroscopic and Theoretical Study of the Grafting Modes of Phosphonic Acids on ZnO Nanorods
Metal oxides are versatile substrates for the design of a wide range of SAM-based organic-inorganic materials among which ZnO nanostructures modified with phosphonic SAM are promising semiconducting systems for applications in technological fields such as biosensing, photonics, and field-effect transistors (FET). Despite previous studies reported on various successful grafting approaches, issues regarding preferred anchoring modes of phosphonic acids and the role of a second reactive group (i.e., a carboxylic group) are still a matter of controversial interpretations. This paper reports on an experimental and theoretical study on the functionalization of ZnO nanorods with monofunctional alkylphosphonic and bifunctional carboxyalkylphosphonic acids. X-ray photoelectron and infrared spectroscopies have been combined with DFT modeling to explain and understand the interactions that drive the surface anchoring of phosphonic acids on ZnO surface. It was found that both monofunctional and bifunctional acids anchor on ZnO through a multidentate bonding which involves both P=O and P-O moieties of the phosphonic group. Moreover, anchored bifunctional acids bend to the surface, promoting a further interaction between surface hydroxyl groups and carboxylic terminations. This secondary interaction can be limited by increasing the surface density of the anchored molecules
Celecoxib inhibits proliferation and survival of chronic myelogeous leukemia (CML) cells via AMPK-dependent regulation of β-catenin and mTORC1/2.
CML is effectively treated with tyrosine kinase inhibitors (TKIs). However, the efficacy of these drugs is confined to the chronic phase of the disease and development of resistance to TKIs remains a pressing issue. The anti-inflammatory COX2 inhibitor celecoxib has been utilized as anti-tumour drug due to its anti-proliferative activity. However, its effects in hematological malignancies, in particular CML, have not been investigated yet. Thus, we tested biological effects and mechanisms of action of celecoxib in Philadelphia-positive (Ph+) CML and ALL cells.We show here that celecoxib suppresses the growth of Ph+ cell lines by increasing G1-phase and apoptotic cells and reducing S- and G2-phase cells. These effects were independent of COX2 inhibition but required the rapid activation of AMP-activated protein kinase (AMPK) and the consequent inhibition mTORC1 and 2. Treatment with celecoxib also restored GSK3β function and led to down-regulation of β-catenin activity through transcriptional and post-translational mechanisms, two effects likely to contribute to Ph+ cell growth suppression by celecoxib.Celecoxib inhibited colony formation of TKI-resistant Ph+ cell lines including those with the T315I BCR-ABL mutation and acted synergistically with imatinib in suppressing colony formation of TKI-sensitive Ph+ cell lines. Finally, it suppressed colony formation of CD34+ cells from CML patients, while sparing most CD34+ progenitors from healthy donors, and induced apoptosis of primary Ph+ ALL cells.Together, these findings indicate that celecoxib may serve as a COX2-independent lead compound to simultaneously target the mTOR and β-catenin pathways, key players in the resistance of CML stem cells to TKIs
Platelet-Rich Plasma (PRP) and Adipose-Derived Stem Cell (ADSC) Therapy in the Treatment of Genital Lichen Sclerosus: A Comprehensive Review
Lichen sclerosus (LS) is a chronic inflammatory dermatosis mostly localized in the genital area, characterized by vulvar alterations that can severely impact a patient's quality of life. Current treatment modalities often provide incomplete relief, and there is a need for innovative approaches to manage this condition effectively. Platelet-rich plasma (PRP) and adipose-derived stem cells (ADSCs) have emerged as potential regenerative therapies for LS, offering promising results in clinical practice. This comprehensive review explores the utilization of PRP and ADSC therapy in the treatment of genital LS, highlighting their mechanisms of action, safety profiles, and clinical outcomes. PRP is a blood product enriched in growth factors and cytokines, which promotes tissue regeneration, angiogenesis, and immune modulation. ADSC regenerative potential relies not only in their plasticity but also in the secretion of trophic factors, and modulation of the local immune response. Numerous studies have reported the safety of PRP and ADSC therapy for genital LS. Adverse events are minimal and typically involve mild, self-limiting symptoms, such as transient pain and swelling at the injection site. Long-term safety data are encouraging, with no significant concerns identified in the literature. PRP and ADSC therapy have demonstrated significant improvements in LS-related symptoms, including itching, burning, dyspareunia, and sexual function. Additionally, these therapies enable many patients to discontinue the routine use of topical corticosteroids. Several studies have explored the efficacy of combining PRP and ADSC therapy for LS. In combination, PRP and ADSCs seem to offer a synergistic approach to address the complex pathophysiology of LS, particularly in the early stages. The use of PRP and ADSC therapy for genital lichen sclerosus represents a promising and safe treatment modality. These regenerative approaches have shown significant improvements in LS-related symptoms, tissue trophism, and histological features. Combination therapy, which harnesses the synergistic effects of PRP and ADSCs, is emerging as a preferred option, especially in early-stage LS cases. Further research, including randomized controlled trials and long-term follow-up, is warranted to elucidate the full potential and mechanisms of PRP and ADSC therapy in the management of genital LS. These regenerative approaches hold great promise in enhancing the quality of life of individuals suffering from this challenging condition
Identification of calcium sensing receptor (CaSR) mRNA-expressing cells in normal and injured rat brain
Calcium sensing receptor (CaSR), isolated for the first time from bovine and human parathyroid, is a G-protein-coupled receptors that has been involved in diverse physiological functions. At present a complete in vivo work on the identification of CaSR mRNA-expressing cells in the adult brain lacks and this investigation was undertaken in order to acquire more information on cell type expressing CaSR mRNA in the rat brain and to analyse for the first time its expression in different experimental models of brain injury. The expression of CaSR mRNAs was found mainly in scattered cells throughout almost all the brain regions. A double labeling analysis showed a colocalization of CaSR mRNA expression in neurons and oligodendrocytes, whereas it was not found expressed both in the microglia and in astrocytes. One week after kainate-induced seizure CaSR was found in the injured CA3 region of the hippocampus and very interestingly it was found up-regulated in the neurons of CA1-CA2 and dentate gyrus. Similarly, 1 week following ibotenic acid injection in the hippocampus, CaSR mRNA expression was increased in oligodendrocytes both in the lesioned area and in the contralateral CA1-CA3 pyramidal cell layers and dentate gyrus. One week after needle-induced mechanical lesion an increase of labeled cells expressing CaSR mRNA was observed along the needle track. In conclusion, the present results contribute to extend available data on cell type-expressing CaSR in normal and injured brain and could spur to understand the role of CaSR in repairing processes of brain injury
New perspectives in the genetic diagnosis of male infertility
The current issue of the Croatian Medical Journal features
two interesting articles on reproductive health. Sengun et
al (1) present their findings of novel mutations in the gene
coding for FK506 binding protein-like (FKBPL) associated
with male infertility, while Bilić et al (2) discuss the benefits of ovarian tissue cryopreservation. In spite of tremendous advances in the field, various aspects of reproductive
health, particularly infertility, still necessitate further study
and development of novel diagnostic and therapeutic approaches
Exercise training reverses myocardial dysfunction induced by CaMKIIδC overexpression by restoring Ca2+-homeostasis
Several conditions of heart disease, including heart failure and diabetic cardiomyopathy, are associated with upregulation of cytosolic Ca2+/calmodulin-dependent protein kinase II (CaMKIIδC) activity. In the heart, CaMKIIδC isoform targets several proteins involved in intracellular Ca2+ homeostasis. We hypothesized that high-intensity endurance training activates mechanisms that enable a rescue of dysfunctional cardiomyocyte Ca2+ handling and thereby ameliorate cardiac dysfunction despite continuous and chronic elevated levels of CaMKIIδC. CaMKIIδC transgenic (TG) and wild-type (WT) mice performed aerobic interval exercise training over 6 wk. Cardiac function was measured by echocardiography in vivo, and cardiomyocyte shortening and intracellular Ca2+ handling were measured in vitro. TG mice had reduced global cardiac function, cardiomyocyte shortening (47% reduced compared with WT, P < 0.01), and impaired Ca2+ homeostasis. Despite no change in the chronic elevated levels of CaMKIIδC, exercise improved global cardiac function, restored cardiomyocyte shortening, and reestablished Ca2+ homeostasis to values not different from WT. The key features to explain restored Ca2+ homeostasis after exercise training were increased L-type Ca2+ current density and flux by 79 and 85%, respectively (P < 0.01), increased sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a) function by 50% (P < 0.01), and reduced diastolic SR Ca2+ leak by 73% (P < 0.01), compared with sedentary TG mice. In conclusion, exercise training improves global cardiac function as well as cardiomyocyte function in the presence of a maintained high CaMKII activity. The main mechanisms of exercise-induced improvements in TG CaMKIIδC mice are mediated via increased L-type Ca2+ channel currents and improved SR Ca2+ handling by restoration of SERCA2a function in addition to reduced diastolic SR Ca2+ leak
Original immunophenotype of blood endothelial progenitor cells and microparticles in patients with isolated arterial erectile dysfunction and late onset hypogonadism: effects of androgen replacement therapy.
Blood endothelial progenitor cells (EPCs) and endothelial microparticles (EMPs) have been proposed as markers of endothelial dysfunction. Aim of this study was to evaluate an original immunophenotype of EPCs and EMPs in patients with isolated arterial erectile dysfunction (ED) and late onset hypogonadism (LOH) before and after androgen replacement therapy.Fifty patients (50-64 years) with ED and LOH were selected. EPC (CD45(neg)/CD34(pos)/CD144(pos)) and EMP (CD45(neg)/CD34(neg)/CD144(pos)) blood concentrations were evaluated by flow cytometry. Thirty patients received androgen replacement therapy (Tostrex® ProStrakan) for 6 months (group A), other 20 patients not received androgen therapy for the contraindications in their clinical history (group B).After 6 months, group B showed IIEF-5 score, peak systolic velocity and acceleration time significantly worse than group A; in addition EPCs and EMPs were significantly higher in group B compared to group A.Patients with isolated arterial ED and LOH not treated with androgen therapy showed worst vascular parameters measured by penile Doppler and higher EPCs and EMPs compared to treated hypogonadal patients, hence, LOH appears to be an additional vascular risk factor, and these markers may be considered as predictors of cavernous artery disease. Finally, androgen therapy improves endothelial dysfunction
LDOC-1 and PARP-1 mRNA expression in leukocytes of father and son with cutaneous malignant melanoma
Abstract
Apoptosis is central to the biology of cutaneous malignant melanoma (CMM). The leucine zipper, down regulated in cancer 1 (LDOC-1) gene, is known to be a regulator of the nuclear factor kappa B (NF-kB) through inhibition of the same NF-kB. The poly (ADP-ribose) polymerase-1 (PARP1) gene plays an important role for the efficient maintenance of genome integrity. PARP-1 protein is required for the apoptosis-inducing factor (AIF) translocation from the mitochondria to the nucleus. We report here two interesting cases of family melanoma, a father and son 84 and 40 years old, respectively. The histological evaluation of the lesions of both men revealed diffused superficial melanoma with epithelioid cells. We evaluated the differential expression of LDOC-1 and PARP-1 mRNA in peripheral blood leukocytes of both the father and son. We found that both LDOC-1 and PARP-1 genes were down-regulated in both patients compared with those of controls. These data suggest that low levels of expression of LDOC-1 and PARP-1 mRNA may be associated with familial melanoma
A retrospective study evaluating the impact of scattering radiation from imaging procedures on oocyte quality during ovarian stimulation for fertility preservation in young breast cancer patients
Purpose: Ovarian stimulation for oocyte and embryo cryopreservation is the standard of care for fertility preservation in young breast cancer patients before gonadotoxic chemotherapy. The procedure should be started as soon as possible to avoid delay of treatment; thus, it is often performed concomitantly with tumor staging assessments. However, questions remain regarding the potential negative impact on oocyte quality that may occur due to exposure to scattered ionizing radiation from imaging techniques when staging assessment is conducted at the same time as ovarian stimulation. Methods: We conducted a retrospective study on all breast cancer patients who performed ovarian stimulation for fertility preservation at our center between November 2012 and May 2020. Results: Gynecologic and oncological characteristics were similar between patients exposed (n = 14) or not (n = 60) to ionizing radiation. Exposed patients started the ovarian stimulation sooner after diagnosis than non-exposed patients (11.5 vs 28 days, respectively, P < 0.01). Cycle parameters, including the median number of oocytes collected (10.5 vs 7, P = 0.16), maturation rates (92.5% vs 85.7%, P = 0.54), and fertilization rates (62.2% vs 65.4%, P = 0.70), were similar between groups. Conclusion: This study shows that scattered ionizing radiation due to staging assessment appears to be safe without compromising follicular growth and maturation. Larger studies on fertility and obstetrical outcomes are needed to confirm these preliminary data
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