An investigation on bloom dynamics of Alexandrium catenella and A. pacificum and toxin accumulation in shellfish along the coast of Qinhuangdao, China.

The dinoflagellate genus Alexandrium comprises most of the toxic bloom-forming species producing paralytic shellfish toxins (PSTs) in the sea. Recently, repeated paralytic shellfish poisoning episodes have been recorded in Qinhuangdao located at the west coast of the Bohai Sea. To elucidate the relationship between toxic Alexandrium blooms and the poisoning episodes, a year-round investigation was carried out in this region from July 2020 to July 2021. Two qPCR assays were used to detect A. catenella and A. pacificum, and LC-MS/MS was applied to analyze PSTs in phytoplankton and shellfish samples. The blooms of A. catenella and A. pacificum were found in April and July, respectively, and PST content in three bivalves exhibited notable increase following the bloom of A. catenella. The results revealed bloom dynamics of the two toxic Alexandrium species in the Bohai Sea for the first time, and further confirmed A. catenella as the causative agent of poisoning episodes.

[Association between duration of fever before treatment and intravenous immunoglobulin resistance in Kawasaki disease]. / å·å´Žç— æ²»ç–—å‰å‘çƒ­æ—¶é—´ä¸Žä¸™ç§çƒè›‹ç™½è€è¯çš„ç›¸å ³æ€§ä¸´åºŠç ”ç©¶.

OBJECTIVES: To examine the association between duration of fever before intravenous immunoglobulin (IVIG) treatment and IVIG resistance in children with Kawasaki disease (KD). METHODS: A retrospective analysis was performed on the medical data of 317 children with KD who were admitted from January 2018 to December 2020. According to the duration of fever before IVIG treatment, they were divided into two groups: short fever duration group (≤4 days) with 92 children and long fever duration group (>4 days) with 225 children. According to the presence or absence of IVIG resistance, each group was further divided into a drug-resistance group and a non-drug-resistance group. Baseline data and laboratory results were compared between groups. A multivariate logistic regression analysis was used to identify the influencing factors for IVIG resistance. RESULTS: In the short fever duration group, 19 children (20.7%) had IVIG resistance and 5 children (5.4%) had coronary artery aneurysm, and in the long fever duration group, 22 children (9.8%) had IVIG resistance and 19 children (8.4%) had coronary artery aneurysm, suggesting that the short fever duration group had a significantly higher rate of IVIG resistance than the long fever duration group (P<0.05), while there was no significant difference in the incidence rate of coronary artery aneurysm between the two groups (P>0.05). In the short fever duration group, compared with the children without drug resistance, the children with drug resistance had a significantly lower level of blood sodium and significantly higher levels of procalcitonin, C-reactive protein, and N-terminal B-type natriuretic peptide before treatment (P<0.05). In the long fever duration group, the children with drug resistance had significantly lower levels of blood sodium and creatine kinase before treatment than those without drug resistance (P<0.05). The multivariate logistic regression analysis showed that a reduction in blood sodium level was associated with IVIG resistance in the long fever duration group (P<0.05). CONCLUSIONS: IVIG resistance in children with KD varies with the duration of fever before treatment. A reduction in blood sodium is associated with IVIG resistance in KD children with a duration of fever of >4 days before treatment.

The relationship between endothelial progenitor cells and pulmonary arterial hypertension in children with congenital heart disease.

BACKGROUND: Pulmonary arterial hypertension (PAH) caused by congenital heart disease (CHD) is very common in clinics. Some studies have shown that PAH is related to the number of endothelial progenitor cells (EPCs), but there is no report on the relationship between PAH and the number of EPCs in children with CHD. METHODS: In this study, a total of 173 cases with CHD (from 0 to 6 years old) were collected. According to the mean pulmonary arterial pressure (mPAP) measured by right heart catheterization, these cases were divided into PAH groups (including high PAH group, mPAP> 25 mmHg, n = 32, and the middle PAH group, 20 mmHg ≤ mPAP≤25 mmHg, n = 30) and non-PAH group (mPAP< 20 mmHg, n = 111). Peripheral blood was taken for flow cytometry, and the number of EPCs (CD133+/KDR+ cells) was counted. The number of EPCs /µL of peripheral blood was calculated using the following formula: EPCs /µL = WBC /L × lymphocytes % × EPCs % × 10- 6. RESULTS: The median EPCs of the non-PAH group, middle PAH group and high PAH group is 1.86/µL, 1.30 /µL and 0.98/µL, respectively. The mPAP decreases steadily as the level of EPCs increases (P < 0.05). After adjustment of gender, age and BMI, the number of EPCs was significantly associated with a decreased risk of high PAH (OR = 0.37, 95% CI: 0.16-0.87, P < 0.05). However, EPCs was not significantly associated with middle PAH (P > 0.05). CONCLUSION: The findings revealed that the EPCs and high PAH in patients with CHD correlate significantly and EPCs may become an effective treatment for PAH in patients with CHD. EPCs may be a protective factor of high PAH for children with CHD.