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1.
Langmuir ; 40(18): 9732-9740, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38668749

RESUMEN

Metal-organic frameworks (MOFs) are highly regarded as valuable adsorbent materials in materials science, particularly in the field of CO2 capture. While numerous single-metal-based MOFs have demonstrated exceptional CO2 adsorption capabilities, recent advancements have explored the potential of bimetallic MOFs for enhanced performance. In this study, a CuCe-BTC MOF was synthesized through a straightforward hydrothermal method, and its improved properties, such as high surface area, smaller pore size, and larger pore volume, were compared with those of the bare Ce-BTC. The impact of the Cu/Ce ratio (1:4, 1:2, 1:1, and 3:2) was systematically investigated to understand how adding a second metal influences the CO2 adsorption performance of the Ce-BTC MOF. Various characterization techniques, including scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and N2 BET surface area analysis, were employed to assess the physical and chemical properties of the bare Ce-BTC and CuCe-BTC samples. Notably, CuCe-BTC-1:2 exhibited superior surface area (133 m2 g-1), small pore size (3.3 nm), and large pore volume (0.14 cm3 g-1) compared to the monometallic Ce-BTC. Furthermore, CuCe-BTC-1:2 demonstrated a superior CO2 adsorption capacity (0.74 mmol g-1), long-term stability, and good CO2/N2 selectivity. This research provides valuable insights into the design of metal-BTC frameworks and elucidates how introducing a second metal enhances the properties of the monometallic Ce-BTC-MOF, leading to improved CO2 capture performance.

2.
World J Mens Health ; 42(2): 321-337, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38164034

RESUMEN

PURPOSE: Varicoceles can be a source of elevated seminal oxidative stress (OS) and sperm DNA fragmentation (SDF). However, it remains unclear whether varicocele repair (VR) could reduce these parameters. This systematic review and meta-analysis (SRMA) aims to investigate the impact of VR on SDF and seminal malondialdehyde (MDA). MATERIALS AND METHODS: A literature search was performed in Scopus, PubMed, Ovid, Embase, and Cochrane databases. This SRMA included randomized controlled trials and observational studies reporting the pre- and postoperative levels of SDF and seminal OS in infertile men with clinical varicocele that underwent VR. Subgroup analyses included techniques of VR and SDF testing. The effect size was expressed as standardized mean difference (SMD). RESULTS: Out of 1,632 abstracts assessed for eligibility, 29 studies with 1,491 infertile men were included. The analysis showed a significant reduction in SDF after VR, compared to preoperative values (SMD -1.125, 95% confidence interval [CI] -1.410, -0.840; p<0.0001) with high inter-study heterogeneity (I²=90.965%). Reduction in SDF was evident with microsurgical technique and non-microsurgical inguinal approaches (SMD -1.014, 95% CI -1.263, -0.765; p<0.0001, and SMD -1.495, 95% CI -2.116, -0.873; p<0.0001), respectively. Reduction in SDF was significant irrespective of testing was done by sperm chromatin dispersion (SMD -2.197, 95% CI -3.187, -1.207; p<0.0001), sperm chromatin structure assay (SMD -0.857, 95% CI -1.156, -0.559; p<0.0001) or TUNEL (SMD -1.599, 95% CI -2.478, -0.719; p<0.0001). A significant decrease in seminal MDA levels was observed following VR (SMD -2.450, 95% CI -3.903 to -0.997, p=0.001) with high inter-study heterogeneity (I²=93.7%). CONCLUSIONS: Using pre- and post-intervention data, this SRMA indicates a significant reduction in SDF and seminal MDA levels in infertile men with clinical varicocele treated with VR. These findings may have important implications for the future management of this selected group of infertile patients.

3.
World J Mens Health ; 42(1): 92-132, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37382284

RESUMEN

PURPOSE: The purpose of this meta-analysis is to study the impact of varicocele repair in the largest cohort of infertile males with clinical varicocele by including all available studies, with no language restrictions, comparing intra-person conventional semen parameters before and after the repair of varicoceles. MATERIALS AND METHODS: The meta-analysis was performed according to PRISMA-P and MOOSE guidelines. A systematic search was performed in Scopus, PubMed, Cochrane, and Embase databases. Eligible studies were selected according to the PICOS model (Population: infertile male patients with clinical varicocele; Intervention: varicocele repair; Comparison: intra-person before-after varicocele repair; Outcome: conventional semen parameters; Study type: randomized controlled trials [RCTs], observational and case-control studies). RESULTS: Out of 1,632 screened abstracts, 351 articles (23 RCTs, 292 observational, and 36 case-control studies) were included in the quantitative analysis. The before-and-after analysis showed significant improvements in all semen parameters after varicocele repair (except sperm vitality); semen volume: standardized mean difference (SMD) 0.203, 95% CI: 0.129-0.278; p<0.001; I²=83.62%, Egger's p=0.3329; sperm concentration: SMD 1.590, 95% CI: 1.474-1.706; p<0.001; I²=97.86%, Egger's p<0.0001; total sperm count: SMD 1.824, 95% CI: 1.526-2.121; p<0.001; I²=97.88%, Egger's p=0.0063; total motile sperm count: SMD 1.643, 95% CI: 1.318-1.968; p<0.001; I²=98.65%, Egger's p=0.0003; progressive sperm motility: SMD 1.845, 95% CI: 1.537%-2.153%; p<0.001; I²=98.97%, Egger's p<0.0001; total sperm motility: SMD 1.613, 95% CI 1.467%-1.759%; p<0.001; l2=97.98%, Egger's p<0.001; sperm morphology: SMD 1.066, 95% CI 0.992%-1.211%; p<0.001; I²=97.87%, Egger's p=0.1864. CONCLUSIONS: The current meta-analysis is the largest to date using paired analysis on varicocele patients. In the current meta-analysis, almost all conventional semen parameters improved significantly following varicocele repair in infertile patients with clinical varicocele.

4.
World J Mens Health ; 41(2): 289-310, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36326166

RESUMEN

PURPOSE: Despite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated the impact of VR on sperm concentration, total motility, and progressive motility, mostly using a before-after analytic approach. No SRMA to date has evaluated the change in conventional semen parameters after VR compared to untreated controls. This study aimed to evaluate the effect of VR on conventional semen parameters in infertile patients with clinical varicocele compared to untreated controls. MATERIALS AND METHODS: A literature search was performed using Scopus, PubMed, Embase, and Cochrane databases following the Population Intervention Comparison Outcome (PICOS) model (Population: infertile patients with clinical varicocele; Intervention: VR [any technique]; Comparison: infertile patients with clinical varicocele that were untreated; Outcome: sperm concentration, sperm total count, progressive sperm motility, total sperm motility, sperm morphology, and semen volume; Study type: randomized controlled trials and observational studies). RESULTS: A total of 1,632 abstracts were initially assessed for eligibility. Sixteen studies were finally included with a total of 2,420 infertile men with clinical varicocele (1,424 patients treated with VR vs. 996 untreated controls). The analysis showed significantly improved post-operative semen parameters in patients compared to controls with regards to sperm concentration (standardized mean difference [SMD] 1.739; 95% CI 1.129 to 2.349; p<0.001; I²=97.6%), total sperm count (SMD 1.894; 95% CI 0.566 to 3.222; p<0.05; I²=97.8%), progressive sperm motility (SMD 3.301; 95% CI 2.164 to 4.437; p<0.01; I²=98.5%), total sperm motility (SMD 0.887; 95% CI 0.036 to 1.738; p=0.04; I²=97.3%) and normal sperm morphology (SMD 1.673; 95% CI 0.876 to 2.470; p<0.05; I²=98.5%). All the outcomes showed a high inter-study heterogeneity, but the sensitivity analysis showed that no study was sensitive enough to change these results. Publication bias was present only in the analysis of the sperm concentration and progressive motility. No significant difference was found for the semen volume (SMD 0.313; 95% CI -0.242 to 0.868; I²=89.7%). CONCLUSIONS: This study provides a high level of evidence in favor of a positive effect of VR to improve conventional semen parameters in infertile men with clinical varicocele. To the best of our knowledge, this is the first SRMA to compare changes in conventional semen parameters after VR with changes in parameters of a control group over the same period. This is in contrast to other SRMAs which have compared semen parameters before and after VR, without reference to a control group. Our findings strengthen the available evidence and have a potential to upgrade professional societies' practice recommendations favoring VR to improve conventional semen parameters in infertile men.

5.
Andrologia ; 54(1): e14251, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34617300

RESUMEN

The purpose of this study was to investigate the efficacy of hCG therapy in hypogonadotropic hypogonadic (HH) azoospermic males along with dissecting the prognostic value of Y-deletion analysis in these patients. Fifty-eight azoospermic infertile males with diminished testosterone levels (≤400 ng/dl) and hypogonadism symptoms were subjected to human chorionic gonadotropin (hCG) therapy, and Y-deletion analysis was undertaken. Post-treatment, 43% (25/58) patients showed improvement in sperm count with 8.6% (5/58) turning severe oligozoospermic, 24.14% (14/58) patients turning oligozoospermic and 10.54% (6/58) turning normozoospermic. Among responders, the mean sperm concentration was 8.47 ± 13.16 million/ml, sperm count was 17.05 ± 26.17 million, sperm motility was 52.59% ± 25.09% and sperm progressive motility was 26.91% ± 20.51%. Seventeen out of 25 (68%) responders and 11/33 (33%) nonresponders showed an improvement in libido post-therapy. A Y-deletion was observed in 8% (2/25) responders and in 39.39% (13 out of 33) nonresponders. The Y-deletions were more often found in nonresponders in comparison with the responders (Fisher's exact probability test, p = .007, one tailed). We conclude that hCG therapy in hypogonadotropic azoospermic males is effective in improving andrological parameters and sperm production and that Y-chromosome deletion analysis has prognostic significance in predicting the success of hCG therapy.


Asunto(s)
Azoospermia , Hipogonadismo , Oligospermia , Azoospermia/tratamiento farmacológico , Azoospermia/genética , Humanos , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/genética , Masculino , Oligospermia/tratamiento farmacológico , Oligospermia/genética , Pronóstico , Motilidad Espermática , Testosterona
6.
Indian J Ophthalmol ; 67(10): 1555-1559, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31546479

RESUMEN

Purpose: To compare refractive measurements of noncycloplegic photoscreener Plusoptix S12R with cycloplegic retinoscopy, noncycloplegic autorefractor, and cycloplegic autorefractor in children. Methods: The study population (200 eyes of 100 children) was divided into two groups: Group 1 (age 3-7 years) and Group 2 (age 8-15 years). In Group 1, Plusoptix was compared with cycloplegic retinoscopy. In Group 2, Plusoptix was compared with cycloplegic retinoscopy and autorefraction. The second group was made because the younger group was found to be uncooperative for autorefraction. Paired t-test and Pearson's correlation were used for statistical analysis. Results: The mean difference in sphere (DS), spherical equivalent (DSE), and cylinder (DC) between cycloplegic retinoscopy and Plusoptix in Group 1 was 0.68 ± 0.55 (P < 0.001), 0.77 ± 0.61 (P < 0.001), and 0.18 ± 0.28 (P < 0.001), respectively. In Group 2, DS, DSE, and DC between cycloplegic retinoscopy and Plusoptix were 0.86 ± 0.49 (P < 0.001), 0.97 ± 0.51 (P < 0.001), and 0.23 ± 0.28 (P < 0.001); between cycloplegic autorefractor and Plusoptix were 0.69 ± 0.47 (P < 0.001), 0.74 ± 0.49 (P < 0.001), and 0.10 ± 0.31 (P = 0.002); and between noncycloplegic autorefractor and Plusoptix were - 0.25 ± 0.39 (P < 0.001), -0.19 ± 0.41 (P < 0.001), and 0.11 ± 0.31 (P < 0.001), respectively. Pearson's correlation coefficients of S, SE, and C between Plusoptix and cycloplegic retinoscopy were 0.948, 0.938, and 0.924 in Group 1 and 0.972, 0.972, and 0.946 in Group 2, and these values were statistically significant. Bland-Altman plots showed good agreement between cycloplegic retinoscopy and Plusoptix in both groups. Plusoptix gave axis values within 10° of cycloplegic retinoscopy in 81.56% of eyes in Group 1 and in 71.44% of eyes in Group 2. Conclusion: Plusoptix photoscreener can be used for prescription of axis of cylinder in children; however, other refractive measurements must be refined by cycloplegic retinoscopy.


Asunto(s)
Errores de Refracción/diagnóstico , Retinoscopía/métodos , Selección Visual/instrumentación , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Midriáticos/administración & dosificación , Estudios Prospectivos , Pupila/efectos de los fármacos , Refracción Ocular/fisiología , Agudeza Visual/fisiología
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