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Near-infrared (NIR) chromophores with analyte tunable emission and absorption properties are highly desirable for developing activatable fluorescence and photoacoustic (PA) probes for bioimaging and disease diagnosis. Here we engineer a class of new chromophores by extending the π-conjugation system of a xanthene scaffold at position 7 with different electron withdrawing groups. It is demonstrated that these chromophores exhibit pH-dependent transition from a spirocyclic "closed" form to a xanthene "open" form with remarkable changes in spectral properties. We further develop fluorescence and PA probes by caging the NIR xanthene chromophores with a dipeptidyl peptidase 4 (DPPIV) substrate. In vitro and live cell studies show that these probes allow activatable fluorescence and PA detection and imaging of DPPIV activity with high sensitivity, high specificity and fast response. Moreover, these two probes allow high-contrast and highly specific imaging of DPPIV activity in a tumour-bearing mouse model in vivo via systemic administration. This study highlights the potential of a xanthene scaffold as a versatile platform for developing high-contrast fluorescence and PA molecular probes.
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BACKGROUND: With the elimination of schistosomiasis in China, its role in the pathogenesis of colorectal cancer (CRC) has decreased. However, the trends, clinicopathological features, surgical treatment patterns, and prognosis of schistosomiasis-associated CRC (SACRC) versus non-schistosomiasis-associated CRC (NSACRC) in China remain unclear. MATERIALS AND METHODS: The percentage trend of SACRC in CRC patients in China was analyzed using data retrieved from the Pathology Registry of Changhai Hospital (2001-2021). Clinicopathological characteristics, surgical treatment patterns, and prognosis-related parameters were compared between the two groups. Multivariate Cox regression analyses were performed for disease-free survival (DFS) and overall survival (OS). RESULTS: A total of 31 153 CRC cases were included, with 823 (2.6%) cases of SACRC and 30 330 (97.4%) cases of NSACRC. The average percentage of SACRC cases has decreased continuously from 3.8 to 1.7% (from 2001 to 2021). Compared with the NSACRC group, the SACRC group had more men, older age at diagnosis, lower BMI, fewer symptoms; higher rates of rectal cancer, comorbidities, KRAS mutation, multiple primary CRC and concomitant polyps; less lymph node metastasis, distant metastasis, vascular invasion, and tumor budding; less preoperative radiotherapy and preoperative chemotherapy; and more positive resection margins and postoperative targeted therapy. There were no significant differences between the two groups regarding laparoscopic surgery, palliative resection, extended radical resection, or ostomy. Moreover, the SACRC group had adverse DFS and similar OS compared with the NSACRC group. In multivariate analyses, schistosomiasis was not an independent predictor of DFS or OS. CONCLUSION: The percentage of SACRC in CRC (2.6%) in our hospital was very low, and it decreased continuously over the last two decades, indicating that schistosomiasis is no longer an important risk factor for CRC in Shanghai, China. Patients with SACRC have distinct clinicopathological, molecular, and treatment-related features and survival rates similar to those with NSACRC.
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Neoplasias Colorrectales , Neoplasias del Recto , Masculino , Humanos , Neoplasias Colorrectales/patología , Estudios Retrospectivos , China/epidemiología , Pronóstico , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Estadificación de NeoplasiasRESUMEN
BACKGROUND: Fishermen and boatmen are a population at-risk for contracting schistosomiasis due to their high frequency of water contact in endemic areas of schistosomiasis in the People's Republic of China (P. R. China). To develop specific interventions towards this population, the present study was designed to assess the knowledge, attitudes and practices (KAPs) towards schistosomiasis of fishermen and boatmen, and to identify the risk factors associated with schistosome infection using a molecular technique in a selected area of Hunan Province in P. R. China. METHODS: A cross sectional survey was conducted in the Dongting Lake Basin of Yueyang County, Hunan Province. A total of 601 fishermen and boatmen were interviewed between October and November 2017. Information regarding sociodemographic details and KAPs towards schistosomiasis were collected using a standardized questionnaire. Fecal samples of participants were collected and tested by polymerase chain reaction (PCR). Logistic regression analysis was conducted to explore the risk factors related to the positive results of PCR. RESULTS: Of the 601 respondents, over 90% knew schistosomiasis and how the disease was contracted, the intermediate host of schistosomes and preventive methods. The majority of respondents had a positive attitude towards schistosomiasis prevention. However, only 6.66% (40/601) of respondents had installed a latrine on their boats, while 32.61% (196/601) of respondents defecated in the public toilets on shore. In addition, only 4.99% (30/601) respondents protected themselves while exposed to freshwater. The prevalence of schistosomiasis, as determined by PCR, among fishermen and boatmen in Yueyang County was 13.81% (83/601). Age, years of performing the current job, number of times receiving treatment, and whether they were treated in past three years were the main influencing factors of PCR results among this population. CONCLUSIONS: Fishermen and boatmen are still at high risk of infection in P. R. China and gaps exist in KAPs towards schistosomiasis in this population group. Chemotherapy, and health education encouraging behavior change in combination with other integrated approaches to decrease the transmission risk in environments should be improved.
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Explotaciones Pesqueras , Conocimientos, Actitudes y Práctica en Salud , Esquistosomiasis/epidemiología , Adulto , Animales , China/epidemiología , Estudios Transversales , Heces/parasitología , Femenino , Educación en Salud , Humanos , Lagos , Masculino , Persona de Mediana Edad , Ocupaciones/estadística & datos numéricos , Prevalencia , Factores de Riesgo , Esquistosomiasis/diagnóstico , Esquistosomiasis/parasitología , Navíos , Encuestas y CuestionariosRESUMEN
Being a zoonotic parasitic disease, schistosomiasis was widely spread in 12 provinces of Southern China in the 1950s, severly harming human health and hindering economic development. The National Institute of Parasitic Diseases at the Chinese Center for Diseases Control and Prevention, and Chinese Center for Tropical Diseases Research (NIPD-CTDR), as the only professional institution focussing on parasitic diseases at the national level, has played an important role in schistosomiasis control in the country. In this article, we look back at the changes of schistosomiasis endemicity and the contribution of NIPD-CTDR to the national schistosomiasis control programme. We review NIPD-CTDR's activities, including field investigations, design of control strategies and measures, development of diagnostics and drugs, surveillance-response of endemic situation, and monitoring & evaluation of the programme. The NIPD-CTDR has mastered the transmission status of schistosomiasis, mapped the snail distribution, and explored strategies and measures suitable for different types of endemic areas in China. With a good understanding of the life cycle of Schistosoma japonicum and transmission patterns of the disease, advanced research carried out in the NIPD-CTDR based on genomics and modern technology has made it possible to explore highly efficient and soft therapeutic drugs and molluscicides, making it possible to develop new diagnostic tools and produce vaccine candidates. In the field, epidemiological studies, updated strategies and targeted intervention measures developed by scientists from the NIPD-CTDR have contributed significantly to the national schistosomiasis control programme. This all adds up to a strong foundation for eliminating schistosomiasis in China in the near future, and recommendations have been put forward how to reach this goal.
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Academias e Institutos , Enfermedades Endémicas/prevención & control , Programas de Gobierno , Programas Nacionales de Salud , Esquistosomiasis Japónica , Animales , Bovinos , China/epidemiología , Erradicación de la Enfermedad , Desarrollo de Medicamentos , Humanos , Moluscocidas , Esquistosomiasis Japónica/tratamiento farmacológico , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/transmisión , VacunaciónRESUMEN
China has made remarkable progress in reducing schistosomiasis caused by Schistosoma japonicum over the past 7 decades but now faces a severe threat from imported schistosomiasis. Results from national surveillance during 2010-2018 indicate integrating active surveillance into current surveillance models for imported cases is urgently needed to achieve schistosomiasis elimination in China.
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Esquistosomiasis/epidemiología , Adulto , Anciano , Animales , China/epidemiología , Erradicación de la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Esquistosomiasis/etiología , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Migrantes , ViajeRESUMEN
BACKGROUND: An "integrated control" strategy has been implemented within seven provinces at highest risk for schistosomiasis along Yangtze River in Peoples' Republic of China (P. R. China) since 2004. Since Oncomelania hupensis is the only intermediate host of the blood fluke (Schistosoma japonicum), controlling the distribution of snails is considered an essential and effective way to reduce the risk of schistosomiasis infection. The study aimed to determine the snail area burden and annual trend among provinces with potential risk for schistosomiasis along the Yangtze River, above and below the Three Gorges Dam (TGD). METHODS: This retrospective study utilized data previously collected from the National Parasitic Diseases Control Information Management System (NPDCIMS) on annual snail surveys from 2009 to 2017. Descriptive statistics were performed for analyzing the snail burden by provinces, counties, type of environmental location and year, and mapping was conducted to present the snails distribution. RESULTS: From 2009 to 2017, the total snail infested area decreased by 4.22%, from 372 253 hm2 to 356 553 hm2 within the seven high risk provinces. The majority of snails were found in the marshland and lake regions, outside of control embankments. The total snail burden trend remained relatively stable in upstream regions above the TGD from 2010 to 2015, while the trend decreased within downstream regions during this period. In 2016 and 2017, the total snail burden trend increased in both upstream and downstream provinces, however, upstream saw a larger increase. From 2009 to 2017, there were a total of 5990 hm2 of newly developed snail areas in the seven study provinces and the majority were concentrated in regions below the TGD, accounting for 5610 hm2 (93.70%). CONCLUSIONS: There has been a decline in total snail counts from 2009 to 2017. Meanwhile, new snail breeding areas were formed mainly within provinces downstream the TGD due to spread of snails, indicated that the oncomelanid snail would be difficult to completely eliminate. We suggest that the national schistosomiasis integrated control strategy, including mollusciding and environmental modification, will need to be enhanced significantly going forward to achieve a greater reduction in snail burden and ultimately to achieve elimination.
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Schistosoma japonicum/aislamiento & purificación , Caracoles/parasitología , Distribución Animal , Animales , China , Estudios Retrospectivos , Estaciones del AñoRESUMEN
World Bank Loan Project (WBLP) for schistosomiasis control conducted from 1992 to 2001, resulted in significant reduction of schistosomiasis morbidity and mortality in People's Republic of China (P.R. China), with implementation of morbidity control. Thereafter, an integrated control strategy, which targeted blocking disease transmission from reservoir hosts to the environment, was initiated in order to conquer schistosomiasis rebound after WBLP completion. Data obtained from the national schistosomiasis control reporting systems was collected and analyzed. The number of confirmed cases and infected cattle decreased significantly from 2002 to 2017, while no infected snails were found by dissection for four consecutive years. However, lake and marshland regions and some parts areas of Yunnan Province require attention for rigorous schistosomiasis control efforts. There is need to strengthen precise interventions and sensitive surveillance to achieve schistosomiasis elimination in P.R. China.
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Bovinos/parasitología , Control de Enfermedades Transmisibles/estadística & datos numéricos , Morbilidad , Vigilancia de la Población , Esquistosomiasis/mortalidad , Esquistosomiasis/prevención & control , Animales , China/epidemiología , Humanos , Esquistosomiasis/epidemiologíaRESUMEN
Organic-inorganic perovskite solar cells have emerged as a promising photovoltaic technology because of their advantages such as low cost, high efficiency, and solution processability. The performance of perovskite solar cells is highly dependent on the crystallinity and morphology of the perovskite films. Herein, we report a simple, one-step anti-solvent deposition process using di-isopropyl ether as a dripping solvent to obtain extremely uniform and highly crystalline CH3NH3PbI3 perovskite films. Compared to toluene, chlorobenzene, chloroform, or diethyl ether, di-isopropyl ether has proven to be a more suitable solvent for an anti-solvent deposition process. The perovskite solar cells fabricated by the anti-solvent deposition process using di-isopropyl ether treatment exhibit an average power conversion efficiency (PCE) of 17.67 ± 0.54% and the highest PCE of 19.07%. Moreover, the higher boiling point of di-isopropyl ether makes the anti-solvent deposition process more tolerant to elevated ambient temperature, which can be carried out at ambient temperatures up to 40 °C. Our results demonstrate that di-isopropyl ether is an excellent dripping solvent in the anti-solvent deposition process for efficient and reproducible perovskite solar cells.
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Despite being widely used as electron acceptor in polymer solar cells, commercially available PC71 BM (phenyl-C71 -butyric acid methyl ester) usually has a "random" composition of mixed regioisomers or stereoisomers. Here PC71 BM has been isolated into three typical isomers, α-, ß1 - and ß2 -PC71 BM, to establish the isomer-dependent photovoltaic performance on changing the ternary composition of α-, ß1 - and ß2 -PC71 BM. Mixing the isomers in a ratio of α/ß1 /ß2 =8:1:1 resulted in the best power conversion efficiency (PCE) of 7.67 % for the polymer solar cells with PTB7:PC71 BM as photoactive layer (PTB7=poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]]). The three typical PC71 BM isomers, even though sharing similar LUMO energy levels and light absorption, render starkly different photovoltaic performances with average-performing PCE of 1.28-7.44 % due to diverse self-aggregation of individual or mixed PC71 BM isomers in the otherwise same polymer solar cells.
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Perovskite solar cells (PSCs) with TiO2 materials have attracted much attention due to their high photovoltaic performance. Aligned TiO2 nanorods have long been used for potential application in highly efficient perovskite solar cells, but the previously reported efficiencies of perovskite solar cells based on TiO2 nanorod arrays were underrated. Here we show a solvothermal method based on a modified ketone-HCl system with the addition of organic acids suitable for modulation of the TiO2 nanorod array films to fabricate highly efficient perovskite solar cells. Photovoltaic measurements indicated that efficient nanorod-structured perovskite solar cells can be achieved with the length of the nanorods as long as approximately 200 nm. A record efficiency of 18.22% under the reverse scan direction has been optimized by avoiding direct contact between the TiO2 nanorods and the hole transport materials, eliminating the organic residues on the nanorod surfaces using UV-ozone treatment and tuning the nanorod array morphologies through addition of different organic acids in the solvothermal process.