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1.
Nat Commun ; 15(1): 4824, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844448

RESUMEN

Precipitation from tropical cyclones (TCs) can cause massive damage from inland floods and is becoming more intense under a warming climate. However, knowledge gaps still exist in changes of spatial patterns in heavy TC precipitation. Here we define a metric, DIST30, as the mean radial distance from centers of clustered heavy rainfall cells (> 30 mm/3 h) to TC center, representing the footprint of heavy TC precipitation. There is significant global increase in DIST30 at a rate of 0.34 km/year. Increases of DIST30 cover 59.87% of total TC impact areas, with growth especially strong in the Western North Pacific, Northern Atlantic, and Southern Pacific. The XGBoost machine learning model showed that monthly DIST30 variability is majorly controlled by TC maximum wind speed, location, sea surface temperature, vertical wind shear, and total water column vapor. TC poleward migration in the Northern Hemisphere contributes substantially to the DIST30 upward trend globally.

2.
Obesity (Silver Spring) ; 32(6): 1047-1058, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38577709

RESUMEN

OBJECTIVE: The objective of this meta-analysis was to quantify the overall effects of gene mutations in the leptin-melanocortin pathway on short- and long-term weight loss after bariatric surgery. METHODS: MEDLINE, PubMed, and Embase were searched, and data were analyzed using ReviewManager (RevMan) version 5.4. The datasets were divided into two subgroups based on postoperative time, and the outcome measure was the percentage of total weight loss. Meta-regression analysis was performed, and the outcome was presented as the weighed mean difference of percentage of total weight loss. RESULTS: The results showed that patients with mutations in the leptin-melanocortin pathway experienced 3.03% lower total weight loss after bariatric surgery (mean difference, -3.03; 95% CI: -3.63 to -2.44), mainly reflected in lower long-term postoperative weight loss (mean difference, -3.43; 95% CI: -4.09 to -2.77), whereas mutation carriers exhibited a magnitude of short-term postoperative weight loss that was similar to patients without such mutations (total difference value, -1.13; 95% CI: -2.57 to 0.31). CONCLUSIONS: Mutations in leptin-melanocortin pathway genes reduce long-term weight loss after bariatric surgery, whereas this effect may not be reflected during the period of rapid weight loss within 12 months. These genetic variants increase the difficulties in maintaining patients' long-term weight loss.


Asunto(s)
Cirugía Bariátrica , Leptina , Mutación , Pérdida de Peso , Humanos , Leptina/genética , Leptina/sangre , Pérdida de Peso/genética , Melanocortinas/genética , Obesidad Mórbida/cirugía , Obesidad Mórbida/genética , Transducción de Señal , Obesidad/cirugía , Obesidad/genética
3.
Front Endocrinol (Lausanne) ; 15: 1333033, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38352711

RESUMEN

Background: Bariatric surgery is an effective approach to weight loss, which may also affect thyroid function. However, alteration in thyroid-stimulating hormone (ΔTSH) and thyroid hormones after bariatric surgery and the relationship between thyroid function and postoperative weight loss still remains controversial. Methods: Data were collected from euthyroid patients with obesity who underwent sleeve gastrectomy and Roux-en-Y gastric bypass from 2017 to 2022. The alterations of free thyroxine (FT4), free triiodothyronine (FT3), total thyroxine (TT4), total triiodothyronine (TT3), and TSH were calculated 1 year after surgery. Pearson correlation analysis was used to assess the correlation between the percentage of total weight loss (%TWL) and ΔTSH. Multivariable linear regression was utilized to determine the association between %TWL and ΔTSH. Results: A total of 256 patients were included in our study. The mean %TWL was 28.29% after 1 year. TSH decreased from 2.33 (1.67, 3.04) uIU/mL to 1.82 (1.21, 2.50) uIU/mL (P < 0.001), FT3 decreased from 3.23 ± 0.42 pg/mL to 2.89 ± 0.41 pg/mL (P < 0.001), FT4 decreased from 1.11 ± 0.25 ng/dL to 1.02 ± 0.25 ng/dL (P < 0.001), TT3 decreased from 1.13 (1.00, 1.25) ng/mL to 0.89 (0.78, 1.00) ng/mL (P < 0.001), and TT4 decreased from 8.28 ± 1.69 ug/mL to 7.82 ± 1.68 ug/mL 1 year postoperatively (P < 0.001). %TWL was found to be significantly correlated to ΔTSH by Pearson correlation analysis (Pearson correlation coefficient = 0.184, P = 0.003), indicating that the more weight loss, the more TSH declined. After adjusting for covariates in multivariable linear regression, %TWL was found to be independently associated with ΔTSH (ß = 0.180 [95% confidence interval (CI), 0.048 - 0.312], P = 0.008). Moreover, %TWL was divided into 3 categorical groups (%TWL ≤ 25%, 25% < %TWL ≤ 35%, and %TWL > 35%) for further exploration, and was also found to be an independent predictor for ΔTSH after adjusting for covariates in multivariable linear regression (ß = 0.153 [95% CI, 0.019 - 0.287], P = 0.025). Conclusion: TSH, FT4, FT3, TT4, and TT3 decrease significantly 1 year after bariatric surgery. The decline in TSH is independently mediated by postoperative weight loss; the more the weight loss, the more the TSH decrease.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Glándula Tiroides , Hormonas Tiroideas , Humanos , Cirugía Bariátrica/efectos adversos , Obesidad Mórbida/cirugía , Estudios Retrospectivos , Glándula Tiroides/fisiología , Tirotropina , Tiroxina , Triyodotironina , Pérdida de Peso
6.
J Opt Soc Am A Opt Image Sci Vis ; 40(11): 2052-2058, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38038071

RESUMEN

Manipulation of polarization states in a complex structured optical field during propagation has become an important topic due to its fundamental interest and potential applications. This work demonstrates the effect of the caustic and twisting phases on the polarization states of a vector beam experimentally and theoretically. The novel properties of polarization evolution, especially the conversions of different states of polarization (SoPs) in a twisted caustic vector beam, occur during propagation in free space because of the modulation of twisting and caustic phases. The orthogonal polarization components tend to appear on the beam centers of two foci, and the two focal distances are closely related to the caustic and twisting phases. The twisting and caustic phases can manipulate the conversions between linear and circular polarization components that occur during propagation. These results provide a new approach to more complex manipulations of a structured optical field, especially in tailoring the evolution of polarization states and two foci. They may find potential applications in the corresponding field.

8.
Surg Today ; 53(6): 702-708, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36737497

RESUMEN

PURPOSE: Single-incision laparoscopic surgery (SILS) has been validated as a safe approach for bariatric surgery. However, as the utilization of SILS in bariatric surgery is still limited by its disadvantages, this study analyzes the outcomes of symmetric three-port laparoscopic Roux-en-Y gastric bypass (STLGB). METHODS: The medical records of patients who underwent STLGB between January 2018 and February 2021 were analyzed retrospectively using an institutional database. The patients were divided into four groups according to their baseline body mass index (BMI). The primary endpoints were operative time, length of stay, complication rate, and weight loss 12 months after surgery. RESULTS: We analyzed the records of 101 patients who underwent STLGB. There was a slight predominance of women (n = 61; 60.4%). The mean operative time was 97.16 ± 38.79 min and the length of stay in the hospital after surgery was 2.79 ± 1.4 days. One patient (0.99%) suffered a gastrojejunal anastomosis leak within 30 days of surgery. There were no significant differences in LOS, complication rate, or cosmetic score among the four groups. The mean BMI reduction was 8.67 kg/m2 and the % total weight loss (%TWL) was 24.37%. Weight loss measured 12 months after surgery was significantly different among the four groups. CONCLUSIONS: STLGB is safe, effective, and feasible for all kinds of patients. It is reproducible with standardization of the procedure.


Asunto(s)
Derivación Gástrica , Laparoscopía , Obesidad Mórbida , Humanos , Femenino , Masculino , Derivación Gástrica/métodos , Obesidad Mórbida/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Laparoscopía/métodos , Índice de Masa Corporal , Pérdida de Peso , Anastomosis en-Y de Roux
11.
Obes Rev ; 24(1): e13516, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36323610

RESUMEN

This study aimed to investigate the prevalence of anemia and related nutrient deficiencies after sleeve gastrectomy (SG). Four online databases were searched for relevant articles. Thirty-one studies with 7639 patients were included in the meta-analysis. The pooled anemia prevalence was 7%, 6%, 9%, 10%, 12%, 25%, 20%, and 18% at baseline, 3 months, 6 months, 12 months, 24 months, 36 months, 48 months, and 60 months, respectively. Although the prevalence of vitamin B12 and folate deficiencies remained low postoperatively, the prevalence of ferritin deficiency steadily increased from 6% at baseline to 27% at 60 months. The prevalence of serum iron deficiency decreased from 13% at baseline to 6% at 24 months and increased to 20% at 60 months. Anemia and ferritin deficiency were strongly correlated (Pearson correlation coefficient = 0.774, p = 0.041). Subgroup analysis suggested that age ≤40 years, preoperative anemia, and insufficient iron supplementations were high-risk factors for postoperative anemia. SG is associated with an increased risk of anemia and decreased iron storage over long-term observation. Routine iron supplementations may reduce anemia after SG; however, the dosages recommended by current guidelines may be insufficient. More strict monitoring schedules and supplementation strategies should be established for the timely detection and management of postoperative anemia.


Asunto(s)
Anemia , Obesidad Mórbida , Humanos , Adulto , Obesidad Mórbida/cirugía , Obesidad Mórbida/complicaciones , Prevalencia , Gastrectomía/efectos adversos , Anemia/etiología , Anemia/complicaciones , Ferritinas , Hierro , Nutrientes
12.
Sci Total Environ ; 825: 153823, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35157861

RESUMEN

Reducing ecological risks is important for promoting regional sustainable development. However, studies on the influence of impervious surfaces on ecological risks and risk control strategies in regions undergoing rapid urbanization are limited. Therefore, this study aimed to demonstrate the spatial-temporal dynamics of regional ecological risks using Beijing as a case study to reveal the influence of impervious surfaces and explore the controlling strategies of risks. We first characterized the ecological risks in Beijing based on the ecosystem service values and mapped the risk levels and temporal variations in risks. We then identified the ecological risk increases caused by impervious surface expansion and built linear regression models for impervious surface coverage (ISC) and risk index. Finally, we formulated ecological risk control strategies for the strategy categories identified based on the ISC thresholds. The results show that the mountainous areas mainly exhibited low ecological risk levels, and the plain areas mainly showed high levels. The expansion of impervious surface was the main cause of the relatively large temporal increase in ecological risks from 2005 to 2015. Moreover, the strategies for ecological risk control can be divided into four categories based on the division of ISC, with 30%, 70%, and 90% as the thresholds. For risk control strategies, reducing ISC is the most important measure to reduce ecological risks for the category with an ISC range of 90%-100%, and increasing the area proportions of forests and water bodies is the most effective measure for the category with an ISC range of 0%-30%. For the other two categories, controlling the ISC and other strategies are required. Our study can increase the understanding of the influences of impervious surfaces on ecological risks in rapidly urbanizing regions and help inform the formulation of strategies for controlling the ecological risks in Beijing.


Asunto(s)
Ecosistema , Urbanización , Beijing , China , Conservación de los Recursos Naturales , Bosques
13.
J Environ Manage ; 277: 111414, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33038674

RESUMEN

This paper explores the differences between public perceptions and existing monitoring indicators in environmental quality in Beijing. The results reveal, existing indicators do not accurately reflect public perceptions of the environment. Some environmental problems, such as fluffy catkins, are not reflected in the existing indicators, yet have a relatively large influence on public perception. The policymakers and public's variegated understanding of the environment, the lag period of public perceptions of environmental quality change, and lack of standards and monitoring for emerging problems are the three main reasons that resulted in a deviation of monitoring indicators from the public perceptions. Resultantly, to improve the level of environmental governance, it is necessary to take relevant measures that reduce the difference between public perceptions and monitoring indicators. Residents should be surveyed regularly to obtain their public perceptions, and the selection of indicators should not be limited to environmental pollution. In particular, some indicators based on public perception should be developed to complement the existing environmental monitoring protocol. In addition, due to the emerging environmental problems, quality standards and monitoring systems should be updated regularly.


Asunto(s)
Conservación de los Recursos Naturales , Política Ambiental , Beijing , Monitoreo del Ambiente
14.
Cancer Biother Radiopharm ; 36(6): 456-466, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32749857

RESUMEN

Background: Long noncoding RNAs (lncRNAs) X inactivate-specific transcripts (XIST) have been found to be dysregulated in breast cancer (BC). Nevertheless, the influence and mechanism of XIST on BC progression remain largely undefined. Methods: The expression levels of XIST, miR-362-5p, and ubiquitin-associated protein 1 (UBAP1) mRNA were detected by quantitative real-time polymerase chain reaction. Cell proliferation, apoptosis, migration, and invasion abilities were determined using MTT assay, flow cytometry, and transwell assay, respectively. Targeted relationship between miR-362-5p and XIST or UBAP1 was validated by the dual-luciferase reporter assay. Western blot was performed to evaluate UBAP1 protein level. Xenograft mice model was established for the investigation of XIST in tumor growth. Results: The authors' data indicated that XIST and UBAP1 were downregulated in BC tissues and cells. XIST overexpression weakened BC cell proliferation, migration, invasion, and facilitated the apoptosis, and XIST silencing exerted opposite effect. Mechanistically, XIST directly interacted with miR-362-5p and miR-362-5p mediated the regulatory effects of XIST overexpression on BC cell malignant behaviors. UBAP1 was a direct target of miR-362-5p. MiR-362-5p exerted its regulatory effects on BC cell behaviors by UBAP1. Moreover, XIST modulated UBAP1 expression through acting a competing endogenous RNA of miR-362-5p. XIST overexpression mediated antiproliferation, antimigration, anti-invasion, and proapoptosis effects were abated by the restored expression of UBAP1 in BC cells. Furthermore, the upregulation of XIST hindered tumor growth in vivo. Conclusion: The current study suggested that XIST overexpression hampered BC cell progression in vitro and in vivo at least partially by targeting the miR-362-5p/UBAP1 axis, illuminating XIST as a promising therapeutic agent for BC management.


Asunto(s)
Neoplasias de la Mama/genética , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Persona de Mediana Edad
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