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1.
Chemosphere ; 366: 143515, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389370

RESUMO

Cadmium (Cd) and arsenic (As) generally exhibit mutually beneficial co-sorption behavior on iron oxyhydroxides through multiple mechanisms, including surface precipitation, ternary surface complexes, and electrostatic interactions. However, the numerous factors that control the immobilization of Cd and As in turn complicated the processes and mechanisms involved in their co-desorption from iron minerals, which hindered the full understanding of their geochemical behaviors. Here, the simultaneous release of Cd(II) and As(V) from newly precipitated ferrihydrite nanoparticles by either Ca or P was investigated through kinetics and isothermal desorption experiments. We showed that the Cd(II) and As(V) present two-phase desorption processes (rapid desorption and slow desorption) in both binary (Fe-Cd or Fe-As alone) and ternary systems (Fe-Cd-As co-presence). Compared to their binary counterparts, Cd(II) and As(V) in the ternary systems are more prone to detachment from ferrihydrite. Further desorption of Cd(II) and As(V) at different co-presence scenarios (different initial concentrations) demonstrated mutual promotion behaviour towards their counterparts; the co-presence of Cd(II) facilitates the desorption of As(V), while the co-presence of As(V) also promotes the desorption of Cd(II). XPS and FTIR results demonstrated that either Ca or P showed minor effects on the binding environment of Cd and As. Further results from the in-situ ATR-FTIR experiment and second derivative peak fitting analysis indicate that the enhanced detachment of Cd(II) and As(V) from the ternary system may be due to the synergistic desorption of the ternary surface complexes and other surface complex species. Our results provide new insights into the prediction of the environmental behaviour of the coexistence of Cd(II) and As(V) in iron-rich geological settings. The potential environmental risks of iron-based remediation methods should be considered due to the enhanced bioavailability of Cd(II) and As(V) in co-presence circumstances.

2.
J Hazard Mater ; 447: 130755, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36640511

RESUMO

Arsenic (As) and cadmium (Cd) often coexist in paddy soils. Nano-ferrihydrite colloidal particles (NFPs) are ubiquitous at redox active interfaces of the paddy system and are well-known to play a critical role in controlling the solubility and bio-availability of As and Cd. However, the mutual interaction between As and Cd on NFPs remains elusive. Herein, batch experiments and in-situ spectroscopic techniques were used to investigate the effects of the interaction pattern (sequential reaction) of Cd(II) and As(V) on their respective adsorption on the surfaces of NFPs. Two scenarios were designed: Cd(II) pre-saturated NFPs and As(V) pre-saturated NFPs. Adsorption of Cd(II) was increased by 1.67, 4.08, and 5.21 times in As(V)-saturated NFPs, but only by 1.05, 1.11, and 1.15 times for As(V) in Cd(II)-saturated NFPs. Further, we determined the pH-dependent mutually beneficial cooperation pathways as mediated by the surface of NFPs. At lower pH (5), As(V) tended to promote Cd(II) adsorption, whereas Cd(II) tended to enhance As(V) adsorption at higher pH (> 5.5). X-ray photoelectron spectroscopy (XPS) indicated that both pre-saturated Cd(II) and As(V) altered the local coordination environment of their counterpart ions. Furthermore, results from in-situ attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR) and second derivative peak shape fitting revealed two types of ternary surface complexes, namely Cd(II)-bridged and As(V)-bridged complexes, which were responsible for the distinct Cd(II) and As(V) co-adsorption behavior on the surface of NFPs under different conditions. These findings help us understand how co-presence Cd and As behave in an iron-rich geological setting and will aid in the development of related restoration technologies.

3.
Front Mol Neurosci ; 15: 842674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35557556

RESUMO

Background: Acupuncture is an effective adjunctive therapy for chronic stable angina pectoris (CSAP), while the underlying mechanism is unclear. This study aimed to investigate the central pathophysiology of CSAP and explore the mechanism of different acupoint prescriptions for CSAP from the perspective of brain-heart interaction. Methods: Thirty-seven CSAP patients and sixty-five healthy subjects (HS) were enrolled, and thirty CSAP patients were divided into two acupoint prescriptions groups (Group A: acupoints on the meridian directly related to the Heart; Group B: acupoints on the meridian indirectly related to the Heart). The Magnetic Resonance Imaging data and clinical data were collected at baseline and after treatment. The comparisons of brain spontaneous activity patterns were performed between CSAP patients and HS, as well as between baseline and after treatment in CSAP patients. Then, the changes in resting-state functional connectivity before and after treatment were compared between the two acupoint prescriptions. Results: Chronic stable angina pectoris patients manifested higher spontaneous activity on the bilateral calcarine, left middle occipital gyrus, right superior temporal gyrus, and right postcentral gyrus. After acupuncture treatment, the spontaneous activity of the left calcarine, left cuneus, and right orbitofrontal gyrus was decreased. The left calcarine was identified as region-of-interest for functional connectivity analysis. Compared with group B, CSAP patients in group A had significantly increased functional connectivity between left calcarine and the left inferior temporal gyrus/cerebellum crus 1, left hippocampus, left thalamus, and left middle cingulate cortex after treatment. Thresholds for all comparisons were p < 0.05, Gaussian Random Field corrected. Conclusion: Regulating the aberrant spontaneous activity of the calcarine might be an underlying mechanism of acupuncture for CSAP. The multi-threaded modulation of functional connectivity between calcarine and multiple pain-related brain regions might be a potential mechanism for better efficacy of acupuncture at points on the meridian directly related to the Heart.

4.
Front Endocrinol (Lausanne) ; 12: 695157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721287

RESUMO

Objective: To determine whether serum anti-Müllerian hormone (AMH) level is a predictor of clinical pregnancy in women trying to achieve a natural conception. Methods: The PubMed, Embase, and Cochrane Library databases were searched for articles published until August 2020. Studies that met the inclusion and exclusion criteria were included in the meta-analysis; no language limitations were imposed. Quality was appraised using the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. Heterogeneity due to the threshold effect was identified; thus, we plotted a summary receiver operating characteristic curve and calculated its area under the summary receiver operating characteristic curve (AUC) and Cochran's Q index to assess whether AMH level is a predictor of spontaneous pregnancy. Publication bias and sensitivity were also assessed. Results: Eleven studies (4,388 women) were ultimately included in this meta-analysis. The AUC and Cochran's Q indices were 0.5932 and 0.5702, respectively. For women younger than 35 years, the AUC was 0.6355 and the Q index was 0.6025. For those older than 35 years, the AUC was 0.5536 and the Q index was 0.5403. Subgroup analyses by study type and population characteristics showed results similar to the overall outcome. No publication bias was identified, and the sensitivity analysis confirmed the robustness of the final result. Conclusions: Serum AMH levels have poor predictive value for natural pregnancy. The predictive value of AMH was poor in the younger and older subgroups. Our findings suggest that low serum AMH levels are not associated with reduced fertility. Introduction: This study investigated the predictive value of anti-Müllerian hormone (AMH) level for natural pregnancy. Other than age, few factors can predict the chances of natural fertility. AMH is an established biomarker of ovarian reserve that is widely used to predict oocyte yield in cases of in vitro fertilization (IVF) and menopause. In clinical practice, the applications of AMH are increasing. However, its predictive value for natural conception remains controversial. In this study, since AMH is closely related with ovarian reserve, we evaluated whether it has predictive value for natural pregnancy. Our findings will fine-tune the clinical application of AMH in pre-pregnancy counseling. The topic should be of wide interest to investigators in the reproductive endocrinology and gynecology fields. Systematic Review Registration: PROSPERO 2020 CRD42020216265, Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020216265.


Assuntos
Hormônio Antimülleriano/sangue , Técnicas de Diagnóstico Obstétrico e Ginecológico , Fertilização/fisiologia , Feminino , Fertilidade/fisiologia , Fertilização in vitro , Humanos , Reserva Ovariana/fisiologia , Indução da Ovulação , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Prognóstico
5.
Front Endocrinol (Lausanne) ; 12: 801026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140685

RESUMO

Objective: To assess and compare the feasibility of progestin-primed ovarian stimulation (PPOS) protocol with mild stimulation protocol for advanced age women with diminished ovarian reserve (DOR) undergoing their first in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycle. Methods: Patients aged ≥35 years and DOR undergoing their first IVF/ICSI cycle were enrolled in this retrospective cohort study: 139 and 600 patients underwent the PPOS and mild stimulation protocols, respectively. The primary outcomes were cumulative clinical pregnancy rate (CCPR) and cumulative live birth rate (CLBR). The secondary outcomes were the number of oocytes retrieved and top-quality embryos. Results: There was nearly no significant difference of baseline characteristics between the two groups. Although a greater amount of total gonadotropin (1906.61 ± 631.04 IU vs. 997.72 ± 705.73 IU, P<0.001) and longer duration of stimulation (9 (10-7) vs. 6 (8-4), P<0.001) were observed in the PPOS group, the number of retrieved oocytes (3 (6-2) vs. 2 (4-1), P<0.001) and top-quality embryos (1 (2-0) vs. 1 (2-0), P=0.038) was greater in the PPOS group than the mild stimulation group. Meanwhile, the incidence of premature luteinizing hormone (LH) surge rate was significantly lower in the PPOS group (0.7% vs.8.3%, P=0.001) than the mild stimulation group. However, there was no significant difference in conservative CCPR, conservative CLBR, optimistic CCPR, and optimistic CLBR between the two groups (all P>0.05). A multivariate logistic regression model showed significant positive effects of the number of retrieved oocytes and number of top-quality embryos on conservative CCPR (OR=1.236, 95%CI: 1.048-1.456, P=0.012, OR=2.313, 95%CI: 1.676-3.194, P<0.001) and conservative CLBR (OR=1.250, 95%CI: 1.036-1.508, P=0.020, OR=2.634, 95%CI: 1.799-3.857, P<0.001) respectively, while significant negative effects of age were identified for conservative CCPR (OR=0.805, 95%CI: 0.739-0.877, P<0.001) and conservative CLBR (OR=0.797, 95%CI: 0.723-0.879, P<0.001). Conclusion: The PPOS protocol is an effective alternative to the mild stimulation protocol for advanced age patients with DOR, as it provides comparable reproductive outcomes and better control of premature LH surge. Further, more oocytes and top-quality embryos were obtained in the PPOS group, which had a positive association with conservative CCPR and CLBR.


Assuntos
Fármacos para a Fertilidade Feminina/uso terapêutico , Fertilização in vitro , Nascido Vivo , Idade Materna , Reserva Ovariana , Indução da Ovulação/métodos , Taxa de Gravidez , Progestinas/uso terapêutico , Adulto , Gonadotropina Coriônica/uso terapêutico , Clomifeno/uso terapêutico , Estudos de Coortes , Didrogesterona/uso terapêutico , Feminino , Humanos , Letrozol/uso terapêutico , Acetato de Medroxiprogesterona/uso terapêutico , Menotropinas/uso terapêutico , Razão de Chances , Recuperação de Oócitos , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas , Pamoato de Triptorrelina/uso terapêutico
6.
Sci Rep ; 10(1): 8732, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457475

RESUMO

The gonadotropin releasing hormone agonist (GnRH-a) long-protocols and the GnRH-antagonist protocols are two commonly used protocols for in vitro fertilization (IVF), but their cost-effectiveness has not been studied, especially in China. A retrospective study involving 1638 individuals in GnRH-a long-protocol and 621 in GnRH-antagonist protocol were conducted and a decision tree model analysis was used to analyze the cost-effectiveness. Both direct and indirect costs were calculated. As a result, during the fresh embryo transplantation cycles, there was no significant difference in the rate of ongoing pregnancy between the two protocols, the average cost of per ongoing pregnancy in the GnRH-antagonist protocol was $ 16970.85, and that in the GnRH-agonist long-protocol was $19902.24. The probability of cumulative ongoing pregnancy per start cycle was estimated at 60.65% for the GnRH-antagonist protocol and 71.6% for the GnRH-agonist long-protocol (P < 0.01). Considering the cumulative ongoing pregnancy rate, the mean costs per ongoing pregnancy were estimated at $8176.76 and at $7595.28 with GnRH-antagonist protocol and GnRH-agonist long protocol, respectively. In conclusion, in fresh embryo transplantation cycle, the GnRH-antagonist protocol has economic advantage. However, the GnRH-agonist long protocol is more cost effective considering the cumulative ongoing pregnancy rate in the fresh embryo and frozen embryo transplantation cycles.


Assuntos
Fertilização in vitro/economia , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Taxa de Gravidez , Adulto , Análise Custo-Benefício , Árvores de Decisões , Feminino , Humanos , Idade Materna , Gravidez , Estudos Retrospectivos
7.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(5): 580-585, 2019 07 25.
Artigo em Chinês | MEDLINE | ID: mdl-31901035

RESUMO

In vitro fertilization and embryo transplantation (IVF-ET) technology is one of the main treatments for infertility. But IVF-ET is expensive and has not be covered by health insurance in most developing countries. Therefore, how to obtain the maximum success rate with the minimum cost is a common concern of clinicians and patients. At present, the economic studies on IVF-ET mainly focus on different ovulation stimulating drugs, different ovulation stimulating protocols, different transplantation methods and the number of transplants. But the process of IVF-ET is complex, the relevant methods of economic study are diverse, and there are no unified standard for outcome indicators, so there is no unified conclusion for more economical and effective protocol by now. Therefore, to analyze the economic studies of IVF-ET, and to explore appropriate evaluation methods and cost-effective protocols will be helpful for reasonable allocation of medical resources and guidance of clinical selection. It would provide policy reference to include the costs of IVF-ET treatment in health insurance in the future.


Assuntos
Economia Médica , Transferência Embrionária , Fertilização in vitro , Economia Médica/tendências , Transferência Embrionária/economia , Transferência Embrionária/estatística & dados numéricos , Feminino , Fertilização in vitro/economia , Fertilização in vitro/estatística & dados numéricos , Humanos , Infertilidade/economia , Seguro Saúde/economia , Seguro Saúde/estatística & dados numéricos , Indução da Ovulação
8.
Neural Regen Res ; 12(5): 831-840, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28616042

RESUMO

Acupuncture is widely used to treat functional dyspepsia with satisfactory outcomes. Combination of the He and Mu acupoints is commonly used and has a synergistic effect on functional dyspepsia; however, its underlying mechanisms remain unclear. Therefore, a randomized controlled parallel clinical trial is currently underway at Chengdu University of Traditional Chinese Medicine, China. This trial is designed to explore the efficacy of and central responses to the He-Mu point combination in patients with functional dyspepsia using functional magnetic resonance imaging. A total of 105 patients with functional dyspepsia will be allocated into 3 groups: the low-He point group (puncturing at Zusanli (ST36)), Mu point group (puncturing at Zhongwan (CV12)), and He-Mu point combination group (puncturing at ST36 and CV12). Every participant will receive 20 sessions of manual acupuncture for 4 weeks. The needles will be inserted perpendicularly to a depth of 1 to 2 cun. The angle of rotation and twisting will range from 90 to 180 degrees, while lifting and thrusting will range from 0.3 to 0.5 cm. The various manipulations will be performed 60 to 90 times per minute. The needles will remain in place for 30 minutes, during which manipulation will be applied every 10 minutes. Magnetic resonance imaging will be performed before and after 20 sessions of acupuncture. The primary outcome is symptom improvement according to the Chinese version of the Nepean Dyspepsia Index. Secondary outcomes include the Leeds dyspepsia questionnaire, Self-Rating Anxiety Scale, Self-Rating Depression Scale, Beck Anxiety Inventory, Beck Depression Inventory, and visual analogue scale scores before and after 10 and 20 sessions of acupuncture. Needle sensation and adverse events will be used to assess the therapeutic effects. This study will promote more widespread awareness of the benefits of acupoint combination in the clinical setting and provide a further explanation of the neuromechanism by which acupuncture at the He-Mu point combination for functional dyspepsia. Registration: Chinese Clinical Trial Registry, ChiCTR-IOR-15006402.

9.
Artigo em Inglês | MEDLINE | ID: mdl-27242911

RESUMO

Using neuroimaging techniques to explore the central mechanism of acupuncture gains increasing attention, but the quality control of acupuncture-neuroimaging study remains to be improved. We searched the PubMed Database during 1995 to 2014. The original English articles with neuroimaging scan performed on human beings were included. The data involved quality control including the author, sample size, characteristics of the participant, neuroimaging technology, and acupuncture intervention were extracted and analyzed. The rigorous inclusion and exclusion criteria are important guaranty for the participants' homogeneity. The standard operation process of acupuncture and the stricter requirement for acupuncturist play significant role in quality control. More attention should be paid to the quality control in future studies to improve the reproducibility and reliability of the acupuncture-neuroimaging studies.

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