35 research outputs found

    Spectrofluorometric investigations on the solvent effects on the photocyclization reaction of diclofenac

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    The solvent effects on the photochemical conversion rate of the photosensitizing drug diclofenac (DCF) were investigated using steady-state fluorescence spectroscopy. The spectral information obtained for the photochemical reaction of DCF in a set of neat solvents demonstrates that the photoconversion reaction rate of DCF is not only medium polarity dependent but also hydrogen-bonding dependent. The solvent effects were qualitatively and quantitatively assessed employing various solvatochromic models, including multi-parameter linear regression analysis (MLRA). Interestingly, the MLRA results (RĀ =Ā 0.99) revealed that the photoconversion rate increases with increasing solvent polarizability (Ļ€*) and H-bond donor capability (Ī±), whereas the rate decreases with increasing hydrogen-bond acceptor capability (Ī²). However, predominant effect of the solvent acidity compared to basicity and polarizability was observed. A hypothesis rationalizing the effects of H-bonding and medium polarity on DCF photoconversion reaction is presented and discussed.Partial support from Qatar University is acknowledged. Open Access funding provided by the Qatar National Library

    Combined experimental and computational investigations of the fluorosolvatochromism of chromeno[4,3-b]pyridine derivatives: Effect of the methoxy substitution

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    Extensive research has been conducted on the spectral properties of chromeno[4,3-b]pyridine derivatives, owing to their potential applications in sensing, optoelectronic devices, and drug discovery. This study presents a comprehensive investigation into the fluorosolvatochromism of selected chromeno[4,3-b]pyridine derivatives, with a particular emphasis on the impact of methoxy substitution. Three derivatives were synthesized and subjected to spectral analysis: chromeno[4,3-b]pyridine-3-carboxylate (I) as the parent compound, and its 7-methoxy (II) and 8-methoxy (III) substituted derivatives. The UVā€“Vis absorption spectra of all derivatives exhibited a broad band with a maximum absorption wavelength that remained unaffected by the surrounding medium. However, distinct fluorescence properties were observed among them. Specifically, derivative II displayed notable fluorescence, while derivatives I and III exhibited no fluorescence properties. Furthermore, derivative II exhibited a fluorescence spectrum that is significantly influenced by the polarity of the medium. To investigate the fluorosolvatochromic behavior in depth, we conducted a comprehensive analysis using various neat solvents with different polarities and hydrogen bonding capabilities. The results obtained revealed a significant positive fluorosolvatochromism, with a bathochromic shift in the fluorescence spectrum as the solvent polarity increased. To understand how specific and non-specific interactions between the solute and the solvent affected the fluorosolvatochromism of II, we employed the four empirical scales model of CatalĆ”n. The obtained results demonstrated that intramolecular charge transfer played a crucial role in the fluorescence behavior of II. To provide a molecular-level explanation for the experimental spectral properties, we utilized the DFT and TD-DFT/B3LYP/6-31 + G(d) computational methods with the IEFPCM implicit solvation approach. The spectral differences between II and III were rationalized in terms of the frontier molecular orbitals (FMOs: the HOMO and LUMO), where distinct natures were observed among the examined derivatives. This study offers valuable insights into the impact of methoxy substitution on the physical and chemical properties of chromeno[4,3-b]pyridine derivatives, specifically concerning their spectral properties as elucidated by their fluorosolvatochromic behavior.The support from Qatar University is thankfully acknowledged. We thank the Central Laboratories Unit at Qatar University for their support in compounds analysis. Major aspects of the calculations were performed using the supercomputing facility at Texas A&M University in Qatar. Open Access funding provided by the Qatar National Library.Scopu

    Updates on androgen replacement therapy and lower urinary tract symptoms: a narrative review

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    Lower urinary tract symptoms (LUTS) are caused by higher tension at the bladder neck level (due to fibrosis or stiffness) or benign prostatic hyperplasia, which causes static obstruction of the bladder outlet. Both forms cause a group of symptoms such as hesitancy, intermittency, weak stream, nocturia, urine frequency, and urgency. Additionally, LUTS (obstructive or irritative symptoms) are common in elderly men with hypogonadism, identified as the reduced testes capability in producing sex steroids and sperm, and are categorized as testosterone deficiency. Even though the mode of action (MoA) of testosterone therapy (TTh) on hypogonadal men needs more researched and understanding, the effectiveness of TTh in the development of male genital organs has been reported in several studies. This review shows the latest updates of TTh in LUTS including potential adverse effects, advantages, and disadvantages

    Testosterone and Covidā€19: An update

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    Abstract: There is overwhelming evidence to suggest that male gender is at a higher risk of developing more severe Covidā€19 disease and thus having poorer clinical outcomes. However, the relationship between testosterone (T) and Covidā€19 remains unclear with both protective and deleterious effects on different aspects of the disease suggested. Here, we review the current epidemiological and biological evidence on the role of testosterone in the process of SARSā€CoVā€2 infection and in mediating Covidā€19 severity, its potential to serve as a biomarker for risk stratification and discuss the possibility of T supplementation as a treatment or preventative therapy for Covidā€19

    The effects of long-term testosterone treatment on endocrine parameters in hypogonadal men: 12-year data from a prospective controlled registry study.

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    Testosterone therapy (TTh) is the primary treatment for aging men with functional hypogonadism. Whilst the benefits of testosterone (T) replacement are well-evidenced, the long-term data for TTh on metabolic and endocrine parameters is limited. Here we present the effect of TTh on endocrine parameters in hypogonadal men at a 12-year follow-up. In this single-centre, cumulative, prospective, registry study, 321 hypogonadal men (mean age: 58.9ā€‰years) received testosterone undecanoate injections in 12-week intervals for up to 12ā€‰years. Blood samples were taken at every other visit to measure levels of total T (TT), calculated free T, sex hormone-binding globulin (SHBG), estradiol, luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone and prolactin. We observed an increase in TT of 15.5ā€‰nmol/L (pā€‰pā€‰pā€‰pā€‰pā€‰pā€‰pā€‰<ā€‰0.0001) were demonstrated at 12-years. The levels of prolactin remained unchanged. Long-term TTh altered hormonal parameters to predictably modify the endocrine system. These effects were sustained during the entire observation time of 12ā€‰years

    The role of Rezum in the management of refractory urinary retention due to benign prostate hyperplasia: A literature review

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    Background: Benign prostatic hyperplasia is the most common cause of urinary retention in men (BPH). The gold standard surgical treatment is transurethral resection of the prostate (TURP). However, due to the morbidity and mortality associated with TURP, more minimally invasive treatments, such as vaporizing the prostate with the Rezum system, have been introduced. We investigated the efficacy of Rezum in the treatment of refractory urinary retention due to BPH in this review. Methodology and materials: To conduct this review, the Cochrane methodology for systematic reviews was used. All studies that used Rezum to treat catheter-dependent patients with enlarged prostates were included. The literature search showed 111 studies, 84 of which were excluded due to non-relevance based on titles and 18 due to lack of relevance based on abstract review. Full manuscripts were reviewed in nine studies, three of which were excluded because they did not meet the inclusion criteria. Results: This review included 301 patients in total. The rate of a successful trial of voiding post Rezum therapy was 85%. The complication rated between 3.8 and 4.3% all of which were mild and self-limited. As there was no major complication of Rezum (clavien dindo >2), the procedure-related morbidity is negligible. Conclusion: In this review, Rezum was found to be an efficacious and safe alternative in the treatment of refractory retention with mild complications and minimal morbidity.The author(s) reported there is no funding associated with the work featured in this article. We would like to thank The Arab Urology Association for providing Open Access funding for this article.Scopu

    Sex-based differences in severity and mortality in COVID-19.

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    The current coronavirus disease (COVID-19) pandemic caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a male bias in severity and mortality. This is consistent with previous coronavirus pandemics such as SARS-CoV and MERS-CoV, and viral infections in general. Here, we discuss the sex-disaggregated epidemiological data for COVID-19 and highlight underlying differences that may explain the sexual dimorphism to help inform risk stratification strategies and therapeutic options

    Estrogens and the risk of breast cancer: A narrative review of literature

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    In female mammals, the development and regulation of the reproductive system and non-reproductive system are significantly influenced by estrogens (oestrogens). In addition, lipid metabolism is another physiological role of estrogens. Estrogens act through different types of receptors to introduce signals to the target cell by affecting many estrogen response elements. Breast cancer is considered mostly a hormone-dependent disease. Approximately 70% of breast cancers express progesterone receptors and/or estrogen receptors, and they are a good marker for cancer prognosis. This review will discuss estrogen metabolism and the interaction of estrogen metabolites with breast cancer. The carcinogenic role of estrogen is discussed in light of both conventional and atypical cancers susceptible to hormones, such as prostate, endometrial, and lung cancer, as we examine how estrogen contributes to the formation and activation of breast cancer. In addition, this review will discuss other factors that can be associated with estrogen-driven breast cancer

    Sex-based differences in severity and mortality in COVID-19.

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    The current coronavirus disease (COVID-19) pandemic caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a male bias in severity and mortality. This is consistent with previous coronavirus pandemics such as SARS-CoV and MERS-CoV, and viral infections in general. Here, we discuss the sex-disaggregated epidemiological data for COVID-19 and highlight underlying differences that may explain the sexual dimorphism to help inform risk stratification strategies and therapeutic options

    Voiding function improves under long-term testosterone treatment (TTh) in hypogonadal men, independent of prostate size

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    Background Functional hypogonadism is a condition in which some, but not all, older men have low testosterone levels. Rather than chronological age per se, the causality of hypogonadism includes obesity and impaired general health (e.g., metabolic syndrome). An association between testosterone deficiency and lower urinary tract symptoms (LUTS) has been reported, yet due to prostate safety concerns, men with severe LUTS (IPSS scoreā€‰>ā€‰19) have invariably been excluded from entering testosterone trials. Irrespective, exogenous testosterone has not been demonstrated to cause de novo or worsen mild to moderate LUTS. Objective This study investigated whether long-term testosterone therapy (TTh) could have a protective effect on improving the symptoms of LUTS in hypogonadal men. However, the exact mechanism by which testosterone exerts is beneficial effect remains uncertain. Patients and methods In this study 321 hypogonadal patients with an average age of 58.9ā€‰Ā±ā€‰9.52 years received testosterone undecanoate in 12-week intervals for 12 years. One hundred and forty-seven of these males had the testosterone treatment interrupted for a mean of 16.9 months before it was resumed. Total testosterone, International Prostate Symptom Scale (IPSS), post-voiding residual bladder volume and aging male symptoms (AMS) were measured over the study period. Results Prior to TTh interruption, it was observed that testosterone stimulation improved the menā€™s IPSS, AMS and post-voiding residual bladder volume, while their prostate volume significantly increased. During the TTh interruption, there was a significant worsening in these parameters, although the increase in prostate volume continued. When TTh was resumed, these effects were reversed, implying that hypogonadism may require lifelong treatment
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