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1.
Asian J Androl ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783630

RESUMO

ABSTRACT: The aim of this study was to compare the accuracies of cognitive fusion-guided targeted biopsy (TB), systematic biopsy (SB), and combined TB+SB for the detection of prostate cancer (PCa) and clinically significant PCa (csPCa) in males with lesions detected by magnetic resonance imaging (MRI). We conducted a retrospective analysis of individuals who underwent prostate biopsy at Peking University People's Hospital (Beijing, China), with an emphasis on patients with both transrectal TB and SB. The main objective was to determine the precisions of SB, TB, and TB+SB for diagnosing PCa and csPCa. We also evaluated the detection rates of TB, SB, TB+ipsilateral-SB (ipsi-SB), TB+contralateral-SB (contra-SB), and TB+SB for PCa and csPCa in patients with unilateral MRI lesions. We compared the diagnostic yields of the various biopsy schemes using the McNemar's test. A total of 180 patients were enrolled. The rates of PCa detection using TB, SB, and TB+SB were 52.8%, 62.2%, and 66.7%, respectively, and the corresponding rates for csPCa were 46.1%, 56.7%, and 58.3%, respectively. Among patients with unilateral MRI lesions, the PCa detection rates for TB, SB, TB+ipsi-SB, TB+contra-SB, and TB+SB were 53.3%, 64.8%, 65.6%, 61.5%, and 68.0%, respectively. TB+ipsi-SB detected 96.4% of PCa and 95.9% of csPCa cases. These findings suggest that the combination of TB+SB has better diagnostic accuracy compared with SB or TB alone. For patients with unilateral MRI lesions, the combination of TB+ipsi-SB may be suitable in clinical settings.

2.
J Orthop Surg (Hong Kong) ; 31(2): 10225536231181706, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37268597

RESUMO

BACKGROUND: The medial plantar artery perforator (MPAP) flap is widely used to reconstruct the weight-bearing area of the foot. Traditionally, its donor site is closed using a skin graft, which is associated with several complications, including walking disability. This study aimed to examine our experience with using a super-thin anterolateral thigh (ALT) flap to reconstruct the MPAP flap donor site. METHODS: We examined 10 patients who underwent reconstruction of the MPAP flap donor site using a super-thin ALT flap between August 2019 and March 2021. The vascular pedicle was anastomosed to the proximal end of the medial plantar vessels or the end of the posterior tibial vessels. RESULTS: All reconstruction flaps survived and all patients were satisfied with the aesthetic appearance. No blisters, ulcerations, hyperpigmentation, or contractures occurred. All patients gained protective sensation in the super-thin ALT flap. The average visual analog scale score for the aesthetic appearance of the reconstructed foot was 8.5 ± 0.7 (range, 8-10). All patients were able to ambulate without aids and could wear regular shoes. The average revised Foot Function Index score was 26.4 ± 4.1 (range, 22-34). CONCLUSION: Reconstruction of the MPAP flap donor site using a super-thin ALT flap is reliable and provides satisfactory functional recovery, aesthetic appearance, and protective sensation while minimizing postoperative morbidity.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Humanos , Coxa da Perna/cirurgia , Retalho Perfurante/irrigação sanguínea , Transplante de Pele , Artérias/cirurgia , Resultado do Tratamento
3.
Br J Pharmacol ; 180(5): 647-666, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36321732

RESUMO

BACKGROUND AND PURPOSE: Gut microbiota dysbiosis induced by acute pancreatitis (AP) exacerbates pancreatic injury and systemic inflammatory responses. The alleviation of gut microbiota dysbiosis through faecal microbiota transplantation (FMT) is considered a potential strategy to reduce tissue damage and inflammation in many clinical disorders. Here, we aim to investigate the effect of gut microbiota and microbiota-derived metabolites on AP and further clarify the mechanisms associated with pancreatic damage and inflammation. EXPERIMENTAL APPROACH: AP rat and mouse models were established by administration of caerulein or sodium taurocholate in vivo. Pancreatic acinar cells were exposed to caerulein and lipopolysaccharide in vitro to simulate AP. KEY RESULTS: Normobiotic FMT alleviated AP-induced gut microbiota dysbiosis and ameliorated the severity of AP, including mitochondrial dysfunction, oxidative damage and inflammation. Normobiotic FMT induced higher levels of NAD+ (nicotinamide adenine dinucleotide)-associated metabolites, particularly nicotinamide mononucleotide (NMN). NMN administration mitigated AP-mediated mitochondrial dysfunction, oxidative damage and inflammation by increasing pancreatic NAD+ levels. Similarly, overexpression of the NAD+ -dependent mitochondrial deacetylase sirtuin 3 (SIRT3) alleviated the severity of AP. Furthermore, SIRT3 deacetylated peroxiredoxin 5 (PRDX5) and enhanced PRDX5 protein expression, thereby promoting its antioxidant and anti-inflammatory activities in AP. Importantly, normobiotic FMT-mediated NMN metabolism induced SIRT3-PRDX5 pathway activation during AP. CONCLUSION AND IMPLICATIONS: Gut microbiota-derived NMN alleviates the severity of AP by activating the SIRT3-PRDX5 pathway. Normobiotic FMT could be served as a potential strategy for AP treatment.


Assuntos
Microbioma Gastrointestinal , Pancreatite , Sirtuína 3 , Camundongos , Ratos , Animais , Pancreatite/tratamento farmacológico , Mononucleotídeo de Nicotinamida/farmacologia , Sirtuína 3/metabolismo , NAD/metabolismo , Disbiose , Ceruletídeo , Doença Aguda , Inflamação
4.
Aging (Albany NY) ; 14(17): 7052-7064, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36069808

RESUMO

AIMS: To determine the potential diagnostic and therapeutic targets of Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). METHODS: We selected the GSE11783, GSE57560 and GSE621 datasets from the GEO database and merged them. R software was used to screen differentially expressed genes (DEGs) between IC/BPS and normal bladder tissues. The "String" online tool is used to analyze DEGs interaction and functional protein enrichment. CIBERSORT online tool was used to analyze the infiltration of immune cells. In addition, we verified the function of BTK in IC/BPS at the clinical samples and cells level. RESULTS: Bioinformatics analysis revealed that 5 genes were significantly overexpressed in IC/BPS, and the protein-protein interaction diagram showed that BTK was a critical link between these five proteins. At the same time, functional enrichment showed that they were significantly related to innate immunity. Immunoinfiltration showed that mast cell resting in IC/BPS was significantly higher. IHC staining of clinical samples showed that the mast cell markers Tryptase and BTK were highly expressed in IC/BPS tissues. At the cell level, knockdown of BTK inhibited proliferation, migration, invasion, and degranulation of mast cells. CONCLUSIONS: This study provides a new perspective for understanding the molecular mechanisms involved in IC/BPS and suggests that BTK may be a target for treating IC/BPS.


Assuntos
Cistite Intersticial , Tirosina Quinase da Agamaglobulinemia/genética , Cistite Intersticial/diagnóstico , Cistite Intersticial/genética , Humanos , Mastócitos , Triptases , Bexiga Urinária
5.
Front Neurol ; 13: 943324, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35899263

RESUMO

Objectives: Spinal muscular atrophy with lower extremity predominance 1 (SMALED1) and Charcot-Marie-Tooth diseasetype 2O (CMT2O) are two kinds of hereditary neuromuscular diseases caused by DYNC1H1 mutations. In this study, we reported two patients with SMALED1 caused by DYNC1H1 mutations. The genotype-phenotype correlations were further analyzed by systematically reviewing previous relevant publications. Materials and Methods: Two patients' with SMALED1 and their parents' clinical data were collected, and detailed clinical examinations were performed. WES was then applied, which was confirmed by Sanger sequencing. PubMed, Web of Science, CNKI, and Wanfang Data were searched, and all publications that met the inclusion criteria were carefully screened. Any individual patient without a detailed description of clinical phenotypes was excluded. Results: The two patients manifested delayed motor milestones and muscle wasting of both lower extremities. The diagnosis was further confirmed as SMALED1. Genetic testing revealed heterozygous DYNC1H1 mutations c.1792C>T and c.790C>G; the latter is a novel dominant mutation. Genotype-phenotype analysis of DYNC1H1 variants and neuromuscular diseases revealed that mutations in the DYN1 region of DYNC1H1 protein were associated with a more severe phenotype, more complicated symptoms, and more CNS involvement than the DHC_N1 region. Conclusion: Our study potentially expanded the knowledge of the phenotypic and genetic spectrum of neuromuscular diseases caused by DYNC1H1 mutations. The genotype-phenotype correlation may reflect the pathogenesis underlying the dyneinopathy caused by DYNC1H1 mutations.

6.
Front Neurol ; 13: 829569, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250834

RESUMO

OBJECTIVES: Amyotrophic lateral sclerosis (ALS) is a progressive, fatal disease with no curative treatment up to now. This study aims to analyze ALS progression of patients treated with mouse nerve growth factor (mNGF), as well as the effects, side effects, and adverse events of the therapy. MATERIALS AND METHODS: A retrospective, observational study was performed including 94 patients with ALS from July 2020 to July 2021. Thirty-two of them were treated with at least one course of mNGF on a regular riluzole use, and the rest 62 were treated with riluzole only. The declining rates of body mass index (BMI) and ALS Functional Rating Scale-Revised (ALSFRS-R) scores were compared between the two groups to indicate ALS progression. RESULTS: No significant differences in ALS progression indicated by the declining rates of BMI and ALSFRS-R score were observed between the two cohorts. ALS progression before and after the first treatment course of mNGF also showed no discernible difference. However, we noticed a moderate 62.7 and 25.1% reduction in the declining rate of BMI and ALSFRS-R motor subscore when comparing mNGF + riluzole treatment to riluzole only. The mNGF treatment was overall safe and well-tolerated, and a rare case of diarrhea was reported after mNGF injection. CONCLUSIONS: Our study revealed that mNGF treatment was overall safe and well-tolerated in patients of ALS. Application of mNGF combined with regular riluzole treatment had no significant clinical effects on delaying ALS progression. Prospective cohort studies and randomized clinical trials based on larger cohorts and longer follow-up times are needed to make a more convincing conclusion.

7.
Orthop Surg ; 14(3): 621-627, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35156309

RESUMO

BACKGROUND: Tendon calcification is a common disease, and it could happen in the tendons of the shoulder, wrist, etc. However, tendon calcification in the superior and inferior gemellus is rare, and in this region is likely to be misdiagnosed. CASE PRESENTATION: Here, our case report first reported a 53-year-old female patient with an unusual case of calcific tendinitis of the gemellus superior and gemellus inferior muscles. The patient presented with severe pain in the right hip and lower extremities, not relieved using nonsteroidal anti-inflammatory drugs (NSAIDs). The preoperative physical examination indicated an abnormality in the hip joint. Preoperative imaging confirmed the results of the physical examination and showed a right hip lesion. We did not make a definite diagnosis preoperatively but considered that the patient might have an osteochondroma. However, surgical findings indicated that the lesion was not in the hip capsule on subsequent arthroscopic surgery, which suggested that the preoperative diagnosis might be wrong. We opened the posterior capsule and found a "toothpaste-like" lesion in the superior and inferior gemellus muscles' tendon. We thought this might be the calcified tendon. Then the arthroscopic surgery was finished to remove the lesion, and the removed tissue was sent to the pathology department for pathological examination. The pathological report confirmed the diagnosis of the calcified tendon. Postoperative follow-up was conducted. The effect of the operation was noticeable. Postoperative symptoms were relieved. CONCLUSIONS: Calcification of the tendons of the superior and inferior gemellus muscles can be easily misdiagnosed, and the disease can be treated minimally with arthroscopy.


Assuntos
Tendinopatia , Artroscopia/métodos , Feminino , Quadril , Humanos , Pessoa de Meia-Idade , Tendinopatia/cirurgia , Tendões/cirurgia , Articulação do Punho
8.
Front Neurol ; 12: 712245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690913

RESUMO

Background: Neurofilaments in cerebrospinal fluid (CSF) and in blood are considered promising biomarkers of amyotrophic lateral sclerosis (ALS) because their levels can be significantly increased in patients with ALS. However, the roles of neurofilaments, especially blood neurofilaments, in the prognosis of ALS are inconsistent. We performed a meta-analysis to explore the prognostic roles of blood neurofilaments in ALS patients. Methods: We searched all relevant studies on the relationship between blood neurofilament levels and the prognosis of ALS patients in PubMed, Embase, Scopus, and Web of Science before February 2, 2021. The quality of the included articles was assessed using the Quality in Prognosis Studies (QUIPS) scale, and R (version 4.02) was used for statistical analysis. Results: Fourteen articles were selected, covering 1,619 ALS patients. The results showed that higher blood neurofilament light chain (NfL) levels in ALS patients were associated with a higher risk of death [medium vs. low NfL level: HR = 2.43, 95% CI (1.34-4.39), p < 0.01; high vs. low NfL level: HR = 4.51, 95% CI (2.45-8.32), p < 0.01]. There was a positive correlation between blood phosphorylated neurofilament heavy chain (pNfH) levels and risk of death in ALS patients [HR = 1.87, 95% CI (1.35-2.59), p < 0.01]. The levels of NfL and pNfH in blood positively correlated with disease progression rate (DPR) of ALS patients [NfL: summary r = 0.53, 95% CI (0.45-0.60), p < 0.01; pNfH: summary r = 0.51, 95% CI (0.24-0.71), p < 0.01]. Conclusion: The blood neurofilament levels can predict the prognosis of ALS patients; specifically, higher levels of blood neurofilaments are associated with a greater risk of death.

12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 263-269, 2020 Apr 28.
Artigo em Chinês | MEDLINE | ID: mdl-32385036

RESUMO

Bladder cancer has high morbidity and mortality rates worldwide. Its incidence is high in western countries and has shown an increasing trend in China. While radical cystectomy combined with pelvic lymph node dissection (PLND) is the standard treatment for bladder cancer,the optimal range of PLND remains controversial. In addition,the prognostic value of lymph node factors is also unclear. This article reviews research advances in PLND.


Assuntos
Excisão de Linfonodo , Neoplasias da Bexiga Urinária/diagnóstico , China , Humanos , Linfonodos , Pelve
14.
FASEB J ; 34(2): 2524-2540, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31908026

RESUMO

The main mechanism of hyaluronidase 1(HYAL-1) in the development of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) was unknown. In this study, a comprehensive inventory of pre-, intra-, and postoperative clinical and biological data of two cohorts (62 pancreatic cancer [PCa] and 111 pancreatic ductal adenocarcinoma [PDAC]) which could induce POPF were retrospectively analyzed. Then, a total of 7644 genes correlated with HYAL-1 was predicted in PDAC tissues and the enriched pathway, kinase targets and biological process of those correlated genes were evaluated. Finally, a mouse pancreatic fistula (PF) model was first built and in vitro studies were performed to investigate the effects of HYAL-1 on PF progression. Our data indicated that preoperative serum HYAL-1 level, pancreatic fibrosis score, and pancreatic duct size were valuable factors for detecting POPF of Grade B and C. The serum HYAL-1 level of 2.07 mg/ml and pancreatic fibrosis score of 2.5 were proposed as the cutoff values for indicating POPF. The bioinformatic analysis and in vitro and in vivo studies demonstrated that HYAL-1 facilitates pancreatic acinar cell autophagy via the dephosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and signal transducers and activators of transcription 3 (STAT3) signaling pathways, which exacerbate pancreatic secretion and inflammation. In summary, the preoperative serum HYAL-1 was a significant predictor for POPF in patients who underwent PD. Tumor-induced HYAL-1 is one of core risk in accelerating PF and then promoting pancreatic secretion and acute inflammation response through the AMPK and STAT3-induced autophagy.


Assuntos
Autofagia/fisiologia , Hialuronoglucosaminidase/sangue , Fístula Pancreática/patologia , Pancreaticoduodenectomia , Adulto , Idoso , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Intestinos/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Fístula Pancreática/diagnóstico , Fístula Pancreática/cirurgia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Estudos Retrospectivos , Fatores de Risco , Neoplasias Pancreáticas
15.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3572-3578, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621245

RESUMO

To evaluate the effects of enhancement release of Chum salmon (Oncorhynchus keta) in Suifen River, the homing Chum salmon was monitored in Dongning section of Suifen River from 2012 to 2017. A total of 462 samples were collected, 41 samples out of which were tagged indivi-duals which were cut off adipose fin before they were released. The recapture rate and the effects of Chum salmon enhancement release were analyzed and evaluated based on the releasing information. The results showed that the entire recapture rate of Chum salmon from 2010 to 2012 was 0.295%, and the input-output ratio of enhancement release was 1:2.87. Both the tagged and non-tagged groups were composed of 1+ to 5+ age individuals, with the average age being 3.93 and 3.63 years, respectively. The fork length at 50% individuals reached sexual maturity (L50) was estimated using a logistic moderating function, which was 53.13 cm and 49.89 cm for tagged and non-tagged groups, respectively. Results from ARSS analysis showed that there was no significant difference in fork length growth between tagged and non-tagged groups, but a significant difference in sexual maturity ratio. Our results confirmed the positive effects of enhancement release on recovery of Chum salmon resource and provided suggestions for the enhancement release efforts.


Assuntos
Oncorhynchus keta , Animais , China , Rios
16.
Food Chem ; 215: 124-8, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27542458

RESUMO

Phloridzin is a nutraceutical. Its use in food, medicine and cosmetics is limited because of its low aqueous solubility and stability limits, but it can be improved by complexing with cyclodextrins. In this study, we investigated the inclusion mechanism between phloridzin and hydroxylpropyl-ß-cyclodextrin (HP-ß-CD) using isothermal titration calorimetry (ITC), ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), proton nuclear magnetic resonance spectroscopy ((1)H NMR) and molecular docking simulations. The ITC results found that the equilibrium binding constant of HP-ß-CD with phloridzin was higher than that of ß-CD. Their inclusion was a spontaneous process with negative ΔG, ΔH and ΔS values. UV spectra showed that the aqueous solubility of phloridzin was enhanced by HP-ß-CD. Our IR analysis verified the inclusion complexation of phloridzin into the HP-ß-CD cavity. The Autodock determined that the substitution distribution of HP-ß-CD influenced not only the orientation and depth degree of phloridzin within the cavity, but also the binding energies.


Assuntos
Florizina/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Calorimetria , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Solubilidade , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
17.
Heart Lung ; 45(5): 429-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27425196

RESUMO

OBJECTIVE: To explore the relationship between inflammation, oxidative stress and poor myocardial perfusion in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PCI). BACKGROUND: Risk factors and mechanisms of poor reperfusion in patients with STEMI after primary PCI remain unclear. METHODS: A total of 143 patients who underwent primary PCI after STEMI were divided into good and poor perfusion groups according to sum-ST-segment resolution (sumSTR) and TIMI myocardial perfusion grade (TMP) results. Aortic sinus arterial blood was collected after primary PCI. The platelet-leukocyte aggregation (PLA), platelet-neutrophil aggregation (PNA), platelet-monocyte aggregation (PMA) and platelet-lymphocyte aggregation (PLyA) were measured by flow cytometry. The malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured by chemical colorimetry. RESULTS: The leukocyte count, neutrophil ratio and high-sensitivity C-reactive protein were significantly higher in the poor perfusion group than the good perfusion group (p < 0.05). Multiple linear regression analysis showed that neutrophil ratio was an independent risk factor of sumSTR in STEMI patients after primary PCI (p < 0.01). The poor myocardial perfusion group had higher levels of PLA, PNA, PMA and MDA (p < 0.05). There were no differences in PLyA and SOD levels between the good and poor myocardial perfusion groups (p > 0.05). CONCLUSION: Inflammation and oxidative stress were related to poor myocardial perfusion in patients with STEMI after primary PCI.


Assuntos
Plaquetas/fisiologia , Circulação Coronária/fisiologia , Leucócitos/fisiologia , Intervenção Coronária Percutânea , Agregação Plaquetária/fisiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Angiografia Coronária , Eletrocardiografia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia
18.
Molecules ; 20(11): 20460-72, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26593891

RESUMO

Peach blossoms were harvested and classified into six developmental stages: (I) bud emerging stage; (II) middle bud stage; (III) large bud stage; (IV) initial-flowering stage; (V) full-flowering stage; and (VI) end-flowering stage. The contents of total phenolics, flavanoids, individual phenolic compounds as well as antioxidant and tyrosinase inhibitory activity of peach blossoms at different developmental stages were investigated. The total phenolic contents varied from 149.80 to 74.80 mg chlorogenic acid equivalents/g dry weight (DW), and the total flavanoid contents ranged from 93.03 to 44.06 mg rutin equivalents/g DW. Both the contents of total phenolics and flavanoids decreased during blossom development. Chlorogenic acid was the predominant component, accounting for 62.08%-71.09% of the total amount of identified phenolic compounds in peach blossom. The antioxidant capacities determined by different assays and tyrosinase inhibitory activity also showed descending patterns during blossom development. Significant correlations were observed between antioxidant capacities with contents of total phenolics and total flavanoids as well as chlorogenic acid, cinnamic acid and kaempferol-3-O-galactoside, while the tyrosinase inhibitory activity had lower correlations with total phenolics and total flavanoids as well as chlorogenic acid, quercetin-3-O-rhamnoside, kaempferol-3-O-galactoside and cinnamic acid. The antioxidant activities of peach blossom seemed to be more dependent on the phenolic compounds than tyrosinase inhibitory activity.


Assuntos
Antioxidantes/química , Inibidores Enzimáticos/química , Flavonoides/química , Flores/química , Fenóis/química , Extratos Vegetais/química , Prunus persica/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Concentração Inibidora 50 , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/farmacologia , Extratos Vegetais/farmacologia
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 2979-84, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26978892

RESUMO

New hyperspectral sensor to detect total ozone is considered to be carried on geostationary orbit platform in the future, because local troposphere ozone pollution and diurnal variation of ozone receive more and more attention. Sensors carried on geostationary satellites frequently obtain images on the condition of larger observation angles so that it has higher requirements of total ozone retrieval on these observation geometries. TOMS V8 algorithm is developing and widely used in low orbit ozone detecting sensors, but it still lack of accuracy on big observation geometry, therefore, how to improve the accuracy of total ozone retrieval is still an urgent problem that demands immediate solution. Using moderate resolution atmospheric transmission, MODT-RAN, synthetic UV backscatter radiance in the spectra region from 305 to 360 nm is simulated, which refers to clear sky, multi angles (12 solar zenith angles and view zenith angles) and 26 standard profiles, moreover, the correlation and trends between atmospheric total ozone and backward scattering of the earth UV radiation are analyzed based on the result data. According to these result data, a new modified initial total ozone estimation model in TOMS V8 algorithm is considered to be constructed in order to improve the initial total ozone estimating accuracy on big observation geometries. The analysis results about total ozone and simulated UV backscatter radiance shows: Radiance in 317.5 nm (R317.5) decreased as the total ozone rise. Under the small solar zenith Angle (SZA) and the same total ozone, R317.5 decreased with the increase of view zenith Angle (VZA) but increased on the large SZA. Comparison of two fit models shows: without the condition that both SZA and VZA are large (> 80°), exponential fitting model and logarithm fitting model all show high fitting precision (R² > 0.90), and precision of the two decreased as the SZA and VZA rise. In most cases, the precision of logarithm fitting mode is about 0.9% higher than exponential fitting model. With the increasing of VZA or SZA, the fitting precision gradually lower, and the fall is more in the larger VZA or SZA. In addition, the precision of fitting mode exist a plateau in the small SZA range. The modified initial total ozone estimating model (ln(I) vs. Ω) is established based on logarithm fitting mode, and compared with traditional estimating model (I vs. ln(Ω)), that shows: the RMSE of ln(I) vs. Ω and I vs. ln(Ω) all have the down trend with the rise of total ozone. In the low region of total ozone (175-275 DU), the RMSE is obvious higher than high region (425-525 DU), moreover, a RMSE peak and a trough exist in 225 and 475 DU respectively. With the increase of VZA and SZA, the RMSE of two initial estimating models are overall rise, and the upraising degree is ln(I) vs. Ω obvious with the growing of SZA and VZA. The estimating result by modified model is better than traditional model on the whole total ozone range (RMSE is 0.087%-0.537% lower than traditional model), especially on lower total ozone region and large observation geometries. Traditional estimating model relies on the precision of exponential fitting model, and modified estimating model relies on the precision of logarithm fitting model. The improvement of the estimation accuracy by modified initial total ozone estimating model expand the application range of TOMS V8 algorithm. For sensor carried on geostationary orbit platform, there is no doubt that the modified estimating model can help improve the inversion accuracy on wide spatial and time range This modified model could give support and reference to TOMS algorithm update in the future.

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