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1.
Aging (Albany NY) ; 13(6): 8524-8540, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33714204

RESUMO

OBJECTIVE: This study explored the therapeutic impact of combined cytotoxic T lymphocyte-associated antigen 4 immunoglobulin (CTLA-4-Ig) treatment and microbubble-mediated exposure in a rat model of diabetic nephropathy (DN). METHOD: We treated rats using CTLA-4-Ig and/or microbubble exposure. At 8 weeks post-intervention, key parameters were evaluated including blood biochemistry, damage to renal tissue, renal parenchymal elasticity, ultrastructural changes in podocytes, and renal parenchymal expression of CD31, CD34, IL-6, Fn, Collagen I, Talin, Paxillin, α3ß1, podocin, nephrin, and B7-1. RESULT: We found that renal function in the rat model of DN can be significantly improved by CTLA-4-Ig and CTLA-4-Ig + ultrasound microbubble treatment. Treatment efficacy was associated with reductions in renal parenchymal hardness, decreases in podocyte reduction, decreased IL-6, Fn and Collagen I expression, increased Talin, Paxillin and α3ß1 expression, elevated podocin and nephrin expression, and decreased B7-1 expression. In contrast, these treatments did not impact CD31 or CD34 expression within the renal parenchyma. CONCLUSION: These findings clearly emphasize that CTLA-4-Ig can effectively prevent podocyte damage, inhibiting inflammation and fibrosis, and thereby treating and preventing DN. In addition, ultrasound microbubble exposure can improve the ability of CTLA-4-Ig to pass through the glomerular basement membrane in order to access podocytes such that combination CTLA-4-Ig + microbubble exposure treatment is superior to treatment with CTLA-4-Ig only.

2.
J Hum Nutr Diet ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33788349

RESUMO

BACKGROUND: Malnutrition is highly prevalent in critically ill patients. Heyland and his colleagues introduced the modified Nutrition Risk in the Critically ill (mNUTRIC) score to evaluate the nutritional risk of patients in intensive care unit (ICU). It was reported that mNUTRIC score was a predictive factor of mortality for patients in medical or mixed ICU, whereas the relationship between mNUTRIC and prognosis of patients in cardiothoracic surgery recovery unit (CSRU) is unclear and related researches are limited. METHOD: We conducted this retrospective cohort study to explore the value of mNUTRIC score in CSRU patients. We identified totally 4,059 patients from the Multiparameter Intelligent Monitoring in Intensive Care III (MIMIC III) database. RESULTS: The optimal cut-off value of mNUTRIC score was 4, and a total of 1,498 (36.9%) patients were considered at high nutritional risk (mNUTRIC ≥4). A multivariate logistic regression model indicated that patients at high nutritional risk have higher hospital mortality compared with those at low nutritional risk (OR=2.49, 95% CI: 1.32-4.70, p=0.005). Further, a Cox regression model was established adjusted for age, white blood cell (WBC), and body mass index (BMI). The Kaplan Meier curve indicated that patients at high nutritional risk have poorer 365-days (HR=1.76, 95% CI: 1.30-2.37, p<0.001)) and 1000-days (HR=2.30, 95% CI: 1.87-2.83, p<0.001) overall survival. CONCLUSION: The mNUTRIC score could not only predict hospital mortality but also be an independent prognostic factor for long-term survival in CSRU patients. More well-designed clinical trials are needed to verify and update our findings.

3.
Ann Surg Oncol ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33768400

RESUMO

BACKGROUND: The application of splenic hilar lymph node (no. 10 LN) dissection (no. 10 LND) for proximal gastric cancer (PGC) remains controversial. This study aimed to investigate the clinical relevance of no. 10 LND from the perspective of long-term survival. METHODS: The main study population included 995 previously untreated patients who underwent laparoscopic radical total gastrectomy between January 2008 and December 2014. Of these 995 patients, 564 underwent no. 10 LND (no. 10D+ group) and the remaining 431 patients did not (no. 10D- group). Propensity score-matching was applied to reduce the effects of confounding factors. The study end points were overall survival (OS) and disease-free survival (DFS). Additionally, 39 patients who received neoadjuvant chemotherapy during the same period also were included as a separate population for analysis. RESULTS: The metastasis rate for no. 10 LN was 10.5 % (59/564). No significant differences were observed in intra- and postoperative complications nor in mortality between the no. 10D+ and no. 10D- groups (all P > 0.05). After 1:1 matching, the two groups were comparable in clinicopathologic characteristics. The no. 10D+ group had significantly better survival than the no. 10D- group (5-year OS: 63.3 % vs 52.2 %, P = 0.003; 5-year DFS: 60.4 % vs 48.1 %, P = 0.013). For the patients who received neoadjuvant chemotherapy, the 5-year OS rates in the no. 10D+ and no. 10D- groups were respectively 50.6 % and 31.3 % (P = 0.150) and the 5-year DFS rates were respectively 51.5 % and 31.3 % (P = 0.123). CONCLUSIONS: Patients with untreated PGC may achieve the benefit of long-term survival from no. 10 LND. For patients with PGC who undergo neoadjuvant chemotherapy, no. 10 LND may not bring survival benefits. However, further validation with a large-sample study is needed.

4.
Cancer Med ; 10(8): 2752-2762, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33734613

RESUMO

BACKGROUND: X-ray repair cross-complementary 5 (XRCC5) and 6 (XRCC6) are critical for DNA repair. Few studies have assessed their association with breast cancer risk, and related gene-environment interactions remain poorly understood. This study aimed to determine the influence of XRCC5/6 polymorphisms on breast cancer risk, and their interactions with cigarette smoking, alcohol consumption, and sleep satisfaction. METHODS: The study included 1039 patients with breast cancer and 1040 controls. Four single-nucleotide polymorphisms of XRCC5 and two of XRCC6 were genotyped. Information about smoking, alcohol consumption, and sleep satisfaction was collected through questionnaires. Odds ratios (OR) and related 95% confidence intervals (95% CI) were assessed using unconditional logistic regression models. Gene-environment interactions were analyzed using logistic regression with multiplicative interaction models. RESULTS: XRCC5 rs16855458 was associated with increased breast cancer risk in the co-dominant (ptrend  = 0.003) and dominant (CA + AA vs. CC, OR = 1.29, 95% CI = 1.07-1.56, p = 0.008) genetic models after Bonferroni correction. The CG + GG genotype of XRCC6 rs2267437 was associated with an increased risk of estrogen receptor-negative/progesterone receptor-negative (ER-/PR-) breast cancer (CG + GG vs. CC: OR = 1.54, 95% CI = 1.12-2.13, p = 0.008) after Bonferroni correction. Moreover, an antagonistic interaction between XRCC5 rs16855458 and alcohol consumption (pinteraction  = 0.017), and a synergistic interaction between XRCC6 rs2267437 and sleep satisfaction were associated with breast cancer risk (pinteraction  = 0.0497). However, these interactions became insignificant after Bonferroni correction. CONCLUSION: XRCC5 rs16855458 was associated with breast cancer risk, and XRCC6 rs2267437 was associated with the risk of ER-/PR- breast cancer. Breast cancer risk associated with XRCC5 and XRCC6 polymorphisms might vary according to alcohol consumption and sleep satisfaction, respectively, and merit further investigation.

5.
Neural Plast ; 2021: 8819169, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763127

RESUMO

Introduction: We studied the impact of vibratory stimulation on the electrophysiological features of digital sensory nerve action potential (SNAP). Methods: The antidromic digit 3 SNAP was recorded in 19 healthy adults before, during, and after applying a vibration to either 3rd or 5th metacarpal phalangeal joint (MCPJ) at 60 Hz and amplitude of 2 mm. 100% supramaximal stimulus intensity was performed in 5 subjects (randomly selected from the 19 subjects) where the SNAP sizes were recorded. Results: The amplitude of digit 3 SNAP declined to 58.9 ± 8.6% when a vibration was applied to MCPJ digit 3. These impacts did not change by increasing the electrical stimulus intensity. The SNAP regained its baseline value immediately after the cessation of vibration stimulation. The magnitude of size reduction of digit 3 SNAP was less when vibration was moved to from MCPJ of digit 3 to MCPJ of digit 5. Discussion. The marked drop of the SNAP size during vibratory stimulation reflects the decreased responsiveness of Aß afferents to electrical stimulation, which deserve further investigation in the study of focal vibration in neurorehabilitation.

6.
Sci Rep ; 11(1): 7183, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785853

RESUMO

We used cardiac magnetic resonance tissue tracking (CMR-TT) to quantitatively analyze the global, regional and layer-specific strain of isolated left ventricular noncompaction (ILVNC). Combined with late gadolinium enhancement (LGE), we initially explored the effect of focal myocardial fibrosis on myocardial strain. CMR was performed in 63 patients with ILVNC and 52 patients without ILVNC (i.e., the control group). The ILVNC group was divided into an LGE(+) group (29 patients) and an LGE(-) group (34 patients) according to the presence or absence of late gadalinum enhancement (LGE). CVI42 software was used to measure global and regional (basal, middle, apical) radial strain (RS), circumferential strain (CS), longitudinal strain (LS), subendocardial LS and subepicardial LS. The basal-apical strain gradient was defined as the apical mean strain minus the basal mean strain. We then compared differences between these strain parameters. The subendocardial-subepicardial LS gradient was defined as the maximum subendocardial LS minus the subepicardial LS. Compared with the control group, the global and regional RS, CS, LS and the subendocardial, subepicardial LS of the ILVNC group were significantly diminished (P < 0.01). Compared with the LGE(-) group, the global and regional RS, CS, LS and the subendocardial, subepicardial LS of the LGE(+) group were significantly diminished (P < 0.05). In the ILVNC group, the basal-apical CS and LS gradient, and the subendocardial-subepicardial LS gradient were significantly lower than those in the control group (P < 0.01). There were significant differences in myocardial strain between patients with and without ILVNC. ILVNC revealed a specific pattern in terms of strain change. The myocardial strain of the cardiac apex and endocardium was significantly lower than that of the cardiac base and epicardium, respectively. Myocardial strain reduction was more significant in ILVNC patients with focal myocardial fibrosis.

7.
Cancer Res Treat ; 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33677846

RESUMO

Purpose: This study aimed to evaluate the effect of preoperative tumour staging deviation (PTSD) on the long-term survival of patients undergoing radical gastrectomy for gastric cancer (RGGC). Materials and Methods: Clinicopathological data of 2 346 patients who underwent RGGC were retrospectively analysed. The preoperative tumour-lymph node-metastasis (TNM) under-staging group (uTNM) comprised patients who had earlier preoperative TNM than postoperative TNM, and the no preoperative under-staging group (nTNM) comprised the remaining patients. Results: There were 1 031 uTNM (44.0%) and 1 315 nTNM cases (56.0%). Cox prognostic analysis revealed that PTSD independently affected the overall survival (OS) after surgery. The 5-year OS was lower in the uTNM group (41.8%) than in the nTNM group (71.6%). The patients less than 65 years old, with lower ASA score, 2~5 cm tumour located at the lower stomach, and cT1 or cN0 preoperative staging would more likely undergo D1+ LND in uTNM (p < 0.05). Logistic analyses revealed that tumour size >2 cm and BMI ≤22.72 kg/m2 were independent risk factors of preoperative TNM tumour under-staging in patients with cT1N0M0 staging (p < 0.05). Conclusion: Underestimated tumour staging is not rare, which possibly results in inadequate LND and affects the long-term survival for patients undergoing RGGC. D2 LND should be carefully performed in patients who are predisposed to this underestimation.

9.
Chemosphere ; 276: 130189, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33725627

RESUMO

The present study aimed at using different types of food waste as a protein source for the fish feeds to produce safe and quality fish. The results showed the concentrations of ∑PAEs in grass crap (0.24 µg g-1 ww) and bighead carp (0.15 µg g-1 ww) fed with Food waste B feeds (mainly containing fruit, vegetable and cereal waste) was significantly lower than those fed Food waste A feeds (mainly containing meat waste) and control feeds (p<0.05), and the highest ∑PAEs concentration (1.75 µg g-1 ww) was found in the mud carp fed with control feeds in experimental ponds (p<0.05). In addition, there was no biomagnification of PAEs in the food chains within the ponds. The health risk assessment results showed no non-carcinogenic and carcinogenic risks from the PAEs via ingestion of the fish fed with food waste feeds for the local residents.

10.
J Diabetes ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33576570

RESUMO

BACKGROUND: The aim of this study is to evaluate the performance of three existing prediction scores which are applicable to adults for identifying nonalcoholic fatty liver disease (NAFLD) in Chinese children. METHODS: We used data from routine check-up based medical records of 1845 children to validate the performance of three existing scoring systems including the hepatic steatosis index (HSI), Zhejiang University index (ZJU index), and triglyceride-glucose index (TyG index) in detection of NAFLD in children. Propensity score matching was applied to adjust for potential confounding effects in both training and validation cohorts. The area under the curve (AUC) of the receiver operating characteristic curve analysis was utilized to assess the performance of the three scoring systems. RESULTS: Children with NAFLD had higher scores of HSI, ZJU index, and TyG index when compared with the control group (children without NAFLD). Elevated HSI, ZJU index, and TyG index scores were significantly associated with the presence of pediatric NAFLD since adjusted odds ratio and 95% CI with per interquartile range elevation of the HSI, ZJU index, and TyG index were 32.81 (20.48, 52.55), 26.31 (16.97, 40.79), and 1.83 (1.57, 2.13), respectively. In terms of discrimination of NAFLD in children, the AUC of the HSI, ZJU index, and TyG index depending on the validation cohort were 0.964, 0.960, and 0.769, respectively. CONCLUSIONS: The HSI and ZJU index could be appropriate noninvasive biomarkers in distinguishing NAFLD in children from their controls with satisfied accuracy, which would emphasize the clinical and public health policy relevance of pediatric NAFLD. Our findings need to be confirmed by additional longitudinal studies.

11.
Chemosphere ; 274: 129771, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33549886

RESUMO

Chlamydomonas reinhardtii has been frequently investigated for its resistance to metals; however, few studies have systematically compared the intracellular and extracellular processes involved in the detoxification of Cd and Pb by this microalga. We found that C. reinhardtii was more tolerant to Pb (concentration for 50% of the maximal effect; EC50: 29.48 ± 8.83 mg L-1) than to Cd (EC50: 12.48 ± 1.30 mg L-1) after 96 h of exposure. Extracellular polymeric substances (EPS), intracellular starch granules, lipid droplets, and glutathione were significantly increased under Cd and Pb treatments. Lead-containing particles were formed outside of the cells exposed to 30 mg L-1 of Pb, whereas no minerals were present when Cd was added. Various EPS functional groups, including -COOH, C-O-C (polysaccharides), and amide I and II (proteins), were involved in the interactions with Cd and Pb. The Pb removal rate (60.46-78.27%) by C. reinhardtii was higher than that of Cd (50.61-59.38%), and the microalgal cells with intact EPS bound more metals than those without EPS. Adsorption accounted for 79.62% of the total Cd accumulation in the low-Cd treatment, whereas absorption dominated the Pb accumulation at low Pb concentrations. The distributions of Cd and Pb in and out of the microalgal cells were reversed when the concentrations of the two metals increased. The detoxification strategies of C. reinhardtii for Cd and Pb were completely different, and these findings may assist in the phycoremediation of metal pollution in aquatic environments.

12.
Surg Endosc ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33591445

RESUMO

BACKGROUND: Due to lacking evidence for confirming the efficacy of performing laparoscopic surgery for locally advanced gastric cancer (LAGC). Therefore, this study aimed to compare the static and dynamic failure patterns after laparoscopic gastrectomy (LG) and open gastrectomy (OG) in LAGC. METHODS: A total of 1792 LAGC patients who underwent radical resection between January 2010 and January 2017 were divided into the LG group (n = 1557) and the OG group (n = 235). Propensity score matching was performed to balance the two groups. Dynamic hazard rates of failure were calculated using the hazard function. Early and late failure were defined as failure occurring before and after 2 years since surgery, respectively. RESULTS: A total of 1175 patients with LAGC were included after matching (LG group, n = 940; OG, n = 235). The failure rate of the whole cohort was 43.2% (508/1175), accounting for 41.4% (389/940) and 50.6% (119/235) in the LG and OG groups, respectively. Although the two groups showed no significant differences in failure rate for any failure type, landmark analysis showed a lower early distant recurrence rate in the stage IIa-IIIb subgroup of the LG group (OG versus LG: 30.3% versus 21.1%, P = 0.004). The dynamic hazard rate peaked at 9.4 months (peak rate = 0.0186) before gradually declining. In stage IIa-IIIb patients, the hazard rate of the OG group remained significantly higher than that of the LG group within the first 2 years in terms of distant recurrence (peak rate: OG versus LG, 0.0091 versus 0.0055). CONCLUSION: Given the differences in early failure between LG and OG, more intensive surveillance for distant recurrence within the first 2 years should be considered for patients with stage IIa-IIIb after OG.

13.
Poult Sci ; 100(2): 835-843, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518137

RESUMO

Magnolol is a multifunctional plant polyphenol. To evaluate the effects of magnolol on laying hens in the late laying period, 360 (50-week-old) laying hens were randomly assigned to 4 dietary treatments: a non-supplemented control diet (C), and control diets supplemented with 100, 200, and 300 mg/kg of magnolol (M100, M200, and M300), respectively. Each treatment had 6 replicates with 15 hens per replicate. Results showed that dietary supplementation of 200 and 300 mg/kg of magnolol increased the laying rate and the M200 group had a lower feed conversion ratio (P < 0.05). Magnolol supplementation (200 and 300 mg/kg) could linearly increase albumen height and Haugh unit of fresh eggs in the late phase of the laying cycle (P < 0.01). And magnolol linearly alleviated the decline of the albumen height and Haugh unit of eggs stored for 14 d (P < 0.01). The total superoxide dismutase activity in the ovaries of M100 group was greater than that in the other treatments (P < 0.05). As dietary magnolol levels increased, villus height of jejunum and ileum linearly increased (P < 0.01). M200 and M300 groups had higher expression level of occludin in the ileum compared with group C (P < 0.01). The level of nitric oxide production and inducible nitric oxide synthase expression in the ileum of M200 group were lower than that in the C group (P < 0.05). In conclusion, dietary supplementation of 200 and 300 mg/kg magnolol can improve hen performance, albumen quality of fresh and storage eggs, and hepatic lipid metabolism in the late laying cycle. Also, magnolol has a good effect on increasing villi and improving the intestinal mucosal mechanical barrier function.

14.
Ann Palliat Med ; 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33548999

RESUMO

BACKGROUND: Nowadays, controlling nutritional status (CONUT) has been used as a prognostic factor in variety of cancers. However, no consensus has been reached on the prognostic value of CONUT in lung cancer. In this study, we aim to investigate the role of CONUT in survival of patients with lung cancer. METHODS: EMBASE, web of science, and Medline were used to search articles in English-language journals. The association between CONUT score and survival of patients with lung cancer was evaluated by using pooled HRs and their 95% CIs. Chi-square test and I-Square was used to test heterogeneity among studies. Analyses were all performed using Stata 13.0 (Stata Corporation, College Station, TX). RESULTS: Eight studies with 1,836 patients were eventually included in this meta-analysis. The pooled results showed that high CONUT score had an unfavorable impact on OS (HR =1.63, 95% CI: 1.30-2.04), DFS (HR =1.75, 95% CI: 1.35-2.26), CSS (HR =1.45, 95% CI: 1.01-2.07) and PFS (HR =1.67, 95% CI: 0.99-2.35), compared with those with low-CONUT. CONCLUSIONS: CONUT can be used as a predictor of prognosis in patients with lung cancer. HighCONUT score was significantly associated with poor OS, DFS, CSS and PFS.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33593748

RESUMO

INTRODUCTION: Despite advances in diabetic retinopathy (DR) medications, early identification is vitally important for DR administration and remains a major challenge. This study aims to develop a novel system of multidimensional network biomarkers (MDNBs) based on a widely targeted metabolomics approach to detect DR among patients with type 2 diabetes mellitus (T2DM) efficiently. RESEARCH DESIGN AND METHODS: In this propensity score matching-based case-control study, we used ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry system for serum metabolites assessment of 69 pairs of patients with T2DM with DR (cases) and without DR (controls). Comprehensive analysis, including principal component analysis, orthogonal partial least squares discriminant analysis, generalized linear regression models and a 1000-times permutation test on metabolomics characteristics were conducted to detect candidate MDNBs depending on the discovery set. Receiver operating characteristic analysis was applied for the validation of capability and feasibility of MDNBs based on a separate validation set. RESULTS: We detected 613 features (318 in positive and 295 in negative ESI modes) in which 63 metabolites were highly relevant to the presence of DR. A panel of MDNBs containing linoleic acid, nicotinuric acid, ornithine and phenylacetylglutamine was determined based on the discovery set. Depending on the separate validation set, the area under the curve (95% CI), sensitivity and specificity of this MDNBs system were 0.92 (0.84 to 1.0), 96% and 78%, respectively. CONCLUSIONS: This study demonstrates that metabolomics-based MDNBs are associated with the presence of DR and capable of distinguishing DR from T2DM efficiently. Our data also provide new insights into the mechanisms of DR and the potential value for new treatment targets development. Additional studies are needed to confirm our findings.

16.
Plant Physiol Biochem ; 160: 365-376, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33550177

RESUMO

Theoretical and experimental studies have demonstrated that temperature is an important environmental factor that affects the regional distribution of plants. However, how to modify the distribution pattern of plants in different regions is a focus of current research. Obtain the information of cold tolerance genes from cold tolerance species, cloning genes with real cold tolerance effects is one of the most important ways to find the genes related to cold tolerance. In this study, we investigated whether transferring the VHA-c gene from Antarctic notothenioid fishes into Arabidopsis enhances freezing tolerance of Arabidopsis. The physiological response and molecular changes of VHA-c overexpressing pedigree and wildtype Arabidopsis were studied at -20 °C. The results showed that the malondialdehyde (MDA) and membrane leakage rates of WT plants were significantly higher than those of VHA-c8 and VHA-c11 plants, but the soluble sugar, soluble protein, proline and ATP contents of WT plants were significantly lower than those of VHA-c8 and VHA-c11 plants under -20 °C freezing treatment. The survival rate, VHA-c gene expression level and VHA-c protein contents of WT plants were significantly lower than those of VHA-c8 and VHA-c11 plants under -20 °C freezing treatment. Correlation analysis showed that ATP content was significantly negatively correlated with MDA and membrane leakage rate, and positively correlated with soluble sugar, soluble protein and proline content under -20 °C freezing treatment. These results demonstrated that overexpression of the VHA-c gene provided strong freezing tolerance to Arabidopsis by increasing the synthesis of ATP and improved the adaptability of plants in low temperature environment.


Assuntos
Arabidopsis/fisiologia , Proteínas de Peixes/fisiologia , Peixes/genética , Congelamento , ATPases Vacuolares Próton-Translocadoras/fisiologia , Animais , Regiões Antárticas , Arabidopsis/genética , Temperatura Baixa , Proteínas de Peixes/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/fisiologia , ATPases Vacuolares Próton-Translocadoras/genética
17.
Exp Parasitol ; 223: 108081, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33549536

RESUMO

Artificial breeding of small yellow croaker (Larimichthys polyactis) was recently achieved, providing a bright future for its commercial farming. In May 2019, a disease outbreak occurred among small yellow croakers in an aquaculture farm near Xiangshan Bay, charactering by white spots spotted on the surface of fish skin, gills and fins. The parasite was preliminarily identified as Cryptocaryon irritans based on morphological feature of the parasite and the symptoms on fish. However, the previously published specific primer pairs failed to confirm the existence of C. iriitans. Six nucleotides mismatches were discovered after mapping specific forward primer back to targeted gene. Therefore, an updated PCR specific primer was developed within the 9th highly variable region of 18S rRNA gene and conserved in all C. irritans sequences available in GenBank database. The specificity was verified in silico by Primer-BLAST against GenBank nucleotide. Laboratory cultured ciliates (Mesanophrys, Pseudokeronopsis and Uronema) as well as natural microbial community samples collected from sea water and river water was used as negative control to verify the specificity of the primer in situ. Besides, tank transfer method was used to evaluate the treatment of the parasite infection. By tank transfer method, 2.00 ± 0.61 out of 10 fish that already sever infected were successfully survived after 8 days treatment, meanwhile the control group died out at d 6. More loss to the treatment group during first five days was observed and may attribute to the combined effect from infection and stress the recent domesticated fish suffered during rotation. Therefore, tank transfer method was also effective to prevent small yellow croaker from further infection, however the loss of the small yellow croaker suffered from stress during rotation also needs to be carefully concerned. In conclusion, this study reported the first diagnose of C. irritans infection on small yellow croaker, provided updated specific primer to detect C. irritans infection on fish body and reported the effect of tank transfer on small yellow croaker treatment.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Nadadeiras de Animais/parasitologia , Nadadeiras de Animais/patologia , Animais , China/epidemiologia , Cilióforos/classificação , Cilióforos/genética , Infecções por Cilióforos/diagnóstico , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Surtos de Doenças/veterinária , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/terapia , Pesqueiros , Brânquias/parasitologia , Brânquias/patologia , Músculo Esquelético/parasitologia , Músculo Esquelético/patologia , Filogenia , RNA Ribossômico 18S/genética , Pele/parasitologia , Pele/patologia , Especificidade da Espécie
19.
Langmuir ; 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33428403

RESUMO

The precise and effective generation of micron-sized droplets is one of the most common and important issues for droplet-based microfluidics. Active droplet generation makes use of additional energy input in promoting interfacial instabilities for droplet generation. Here, we report a new technique for the active generation of femtoliter droplets in microfluidic systems using confined interfacial vibration (CIV). The CIV is formed at the orifice of a traditional inkjet nozzle first by pushing the liquid out and then pulling it back. Droplets are pinched off during the withdrawal process, and this is different from the current active droplet generation techniques, which only monodirectionally push the liquid out. Droplets with radius ranging from ca. 1 to 28 µm can be actively generated by CIV at an orifice with radius 30 µm, distinguishing from conventional active generation techniques in which the droplets are always comparable or slightly bigger than the orifice. Experimental results showed that the droplet volume can be customized by controlling the intensity of the CIV. The inherent digital nature of the inkjet technique enables easy and precise regulating of the droplet volume, making it seamlessly compatible with the digital microfluidic systems.

20.
Science ; 371(6527): 380-386, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33479149

RESUMO

Z-Olefins are challenging synthetic targets owing to their relative thermodynamic instability. Transition metal-catalyzed asymmetric allylic substitution reactions are well known for installing stereocenters adjacent to branched or E-linear olefins. However, analogous reactions for the synthesis of optically active Z-olefin products are rare. Here we report iridium-catalyzed asymmetric allylic substitution reactions that retain Z-olefin geometries while establishing an adjacent quaternary stereocenter. The formation of transient anti-π-allyl-iridium intermediates and their capture by external nucleophiles before isomerization to the thermodynamically more stable syn-π-allyl-iridium counterparts have been observed. These results provide a promising method for preparing chiral Z-olefinic compounds.

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