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Extant species of the dinoflagellate genus Gonyaulax are capable of producing resting cysts morphologically similar to different cyst-based genera, and their cyst-theca relationships are far from resolved. Here we have carried out germination experiments on several living cysts that resemble Spiniferites delicatus from the subtropical regions of China and Mexico. Both cyst and theca morphology were examined by light and scanning electron microscopy. A new species, Gonyaulax pospelovana, is described, characterized by a cingulum displacement and an overhang of twice its width, and two short antapical spines. The cysts of G. pospelovana had a granular surface and gonal processes with petaloid tips. Maximum likelihood and Bayesian inference analyses based on LSU and SSU rRNA gene sequences revealed that strains identified as G. pospelovana were monophyletic, forming a sister clade to Gonyaulax ellegaardiae and several presumable strains of Gonyaulax spinifera. One Chinese strain and two Mexican strains of G. pospelovana were examined for yessotoxin production using LC-MS/MS, but were not found to produce a detectable amount of toxins. Metabarcoding targeting the 18S V4 rRNA gene was performed on monthly collected samples in Xiamen Bay, China. A ZOTU (zero-radius operational taxonomic units) was detected that was consistent with G. pospelovana. Its maximum abundance was recorded in summer. Additionally, an OTU was identified as G. pospelovana from the Tara Oceans metabarcoding data, which occurred in the Indian and Pacific oceans at temperatures ranging from 28°C to 31°C, suggesting that it is a warm water species. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic caused by SARS-CoV-2 dominated the year 2020 and has an unprecedented impact on global air transport. This paper tries to make an overall review on the interaction of air transport and the COVID-19 pandemic. Although the confirmed cases were first reported in China, the origin of the pandemic remains uncertain. China was the first country to control the COVID-19 pandemic, and domestic air traffic recovers at a fast pace. Compared to 2019 level, world scheduled capacity, passengers carried, and revenues for 2020 were reduced by 50%, 60%, and $371 billion, respectively. Compared with domestic passenger traffic, international passenger traffic reduces more seats, passengers, and revenues. Because air transport contributes to economic growth, many countries or regions provide aviation bailout. The US provides most direct aid, while China mostly provides policy measures. In the post-COVID-19 period, IATA suggests that accepting vaccinated passengers is the best practice to reopen borders. Air cargo will play an important role in the distribution of COVID-19 vaccines. Meanwhile, air transport should be more digitalized, sustainable, and responsible in the future. [ABSTRACT FROM AUTHOR]

Background: Talaromyces marneffei (T. marneffei) infection has been associated with adult-onset immunodeficiency due to anti-IFN-γ autoantibodies. We aimed to investigate the clinical features of non-HIV-infected patients with T. marneffei infection in southern China.Methods: Between January 2018 and September 2020, we enrolled patients with T. marneffei infection who were HIV-negative (group TM, n = 42), including anti-IFN-γ autoantibody-positive (group TMP, n = 22) and anti-IFN-γ autoantibody-negative (group TMN, n = 20) patients and healthy controls (group HC, n = 40). Anti-IFN-γ autoantibodies were detected by ELISA. Clinical characteristics and clinical laboratory parameters were recorded.Results: Compared with anti-IFN-γ autoantibody-negative patients with T. marneffei infection, anti-IFN-γ autoantibody-positive patients did not have underlying respiratory disease; more frequently exhibited dissemination of systemic infections with severe pleural effusion; had higher WBC counts, C-reactive protein levels, erythrocyte sedimentation rates, and neutrophil and CD8+ T cell counts; had lower hemoglobin levels; and were more likely to have other intracellular pathogen infections. Most of these patients had poor outcomes despite standardized antimicrobial therapy.Conclusion: T. marneffei-infected patients with higher anti-IFN-γ autoantibody titers have more severe disease and complex clinical conditions. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization (WHO) in 2015 stated that every effort should be made to provide cesarean delivery (CD) for women in need. In China, the two-child policy largely prompts the number of advanced age childbirth, which raises the possibility of an increasing number of women who need a c-section. The aim of this study was to assess the trends in the overall and medical indication-classified CD rates in the era of the two-child policy in Jiangsu, China.Methods: A retrospective cross-sectional study of 291,448 women who delivered in 11 hospitals in Jiangsu province between 2012 and 2019 was conducted. Medical cesarean indication for each woman was ascertained by manually reviewing the medical records. The 291,448 women were divided into two subgroups according to the presence of the indications: the indicated group (7.80%) and the non-indicated group (92.20%). We then fitted joinpoint regression and log-binomial regression models to estimate trends in the CD rates across the study period.Results: The overall CD rate was observed with a declining trend from 52.51% in 2012-2015 to 49.76% in 2016-2019 (adjusted RR, 0.92; 95% CI, 0.91-0.93; P < 0.001), along with an annual percentage change (APC) to be - 1.0 (95% CI, - 2.1 to 0.0) across the period. The participants were then divided into two subgroups according to the presence of medical CD indications: the indicated group (7.80%) and the non-indicated group (92.20%).We found the declining trend was most pronounced in the non-indicated group, with the CD rates decreased from 50.02% in 2012-2015 to 46.27% in 2016-2019 (adjusted RR, 0.90; 95% CI, 0.89-0.90; P < 0.001). By contrast, we observed a steady trend in the CD rate of the indicated group, which maintained from 87.47% in 2012-2015 to 86.57% in 2016-2019 (P = 0.448). In the indicated group, a higher risk of adverse pregnancy outcomes was revealed for those women who delivered vaginally as compared with those who received c-section. We further investigated that women with following specific indications had a higher proportion of vaginal delivery, i.e., pregnancy complications, fetal macrosomia, and pregnancy complicated with tumor (34.70%, 10.84%, and 16.34%, respectively). Women with the above 3 indications were observed with a higher risk of adverse pregnancy outcomes if delivered vaginally. The incidence rates of the medical indications among the general population increased considerably over the 8-year period (P < 0.001).Conclusions: Although the overall CD rate apparently decreased in the recent years, along with the decline of the unnecessary CD rate, a considerable proportion of indicated women were not provided with CD service in Jiangsu, China. Instead of targeting the overall CD rate, we need to take actions to reduce unnecessary CD rate and provide adequate c-section service for women with indications, particularly for those with underlying diseases and suspected fetal macrosomia. [ABSTRACT FROM AUTHOR]

A Gymnodinium-like dinoflagellate, Kirithra sigma sp. nov., was isolated from Jiaozhou Bay, China, and the southern coast of Korea, and examined by light, scanning, and transmission electron microscopy. Pigment composition and nuclear-encoded partial large subunit ribosomal RNA (LSU rRNA) gene were determined. Cells were oval-shaped (26.4‒36.4 μm long and 17.7‒27.2 μm wide), with a conical epicone and hemispherical hypocone. Its cingulum and sulcus were deep and wide. The cingulum encircled the cell completely, its ends slightly overlapping and displaced one to two cingular widths; the sulcus and sulcal extension formed a sigmoid curve. The anterior sulcal extension contacted the apical structure complex (ASC). The ASC formed a complete circle, consisting of three parallel series of vesicles, and the amphiesmal vesicles within ASC were arranged with one central vesicle (sometimes two) encircled by approximately three rows of polygonal amphiesmal vesicles. Polygonal amphiesmal vesicles of different sizes covered the whole cell surface. The subspherical nucleus was located in the hypocone. Pigment analysis showed that peridinin was the main accessory pigment. The present species is morphologically similar to Kirithra asteri but differs in numbers and rows of amphiesmal vesicles within the ASC, absence of ventral pore, and a sigmoid curve formed by the sulcus and sulcal extension. The partial LSU rRNA gene sequence (c. 1400 bases) of K. sigma differed by c. 5.3% from that of K. asteri. Molecular phylogeny revealed that K. sigma formed an independent sister clade to K. asteri, indicating they are congeneric but different species. [ABSTRACT FROM AUTHOR]

• A species identified as Cochlodinium geminatum and Polykrikos geminatus reclassified. • The species was re-described as Pseudocochlodinium profundisulcus gen. et sp. nov. • Redescription based on characteristic ASC, cingulum, sulcus and molecular phylogeny. • DNA metabarcoding found a wide distribution of the species in the coastal sediments of China. • Analyzed on rRNA gene sequences suggest a possible S-N expansion or warm water preference. Harmful algal blooms (HABs) caused by an unknown dinoflagellate species have frequently occurred in the Pearl River Estuary, China Since 2006. These blooms were associated with severe water discoloration and economic losses, ranging from several km2 to 300 km2 with the maximum recorded cell density being 2.77 × 107 cells⋅L−1. This unknown dinoflagellate species was initially identified as Cochlodinium geminatum and subsequently reclassified as Polykrikos geminatus. However, after reviewing the original descriptions for Cochlodinium geminatum sensu Schütt (1895) and the genus Polykrikos , we considered this species is incongruent with their original descriptions. Further morphological examinations and particularly phylogenetic analyses based on the SSU and partial LSU rRNA genes of isolates and resting cysts from China and Japan prompted us to consider it a new species of a new genus. This new species was proposed to be Pseudocochlodinium profundisulcus gen. et sp. nov., based on its open comma-shaped apical structure complex (ASC), cingulum encircling the cell less than one and a half turns, a deep sulcus with a torsion of a half turn, either single cell or cell chain consisting of two cells with the same number of nuclei and zooids, the resting cyst bearing lobed ornaments, and the evolutionary distances from Polykrikos (and others) on the phylogenetic trees constructed using the concatenated SSU and partial LSU rRNA gene sequences. Metabarcoding investigation of surface sediment samples collected in China revealed that the species to be widely present along the entire Chinese coast with the highest abundance in the South China Sea. Further re-analysis of the Tara Oceans metabarcoding dataset targeting the SSU rRNA gene V9 domain suggested a global distribution of this new genus. Phylogenetic analyses on 46 OTUs (average length: ∼552 bases) of its LSU rRNA gene sequences (mainly D1-D2 domains) obtained from surface sediment samples revealed intraspecific genetic diversity of this species. Interestingly, based on the different distributions and the abundance of these OTUs along the coast of China, this species appeared to have expanded its distribution from the South China Sea to the northern Yellow Sea, or preferred a warm water habitat. We consider that the present work improves the taxonomy and provides important insights into the biogeography of Pseudocochlodinium profundisulcus.⋅ [ABSTRACT FROM AUTHOR]

In Japanese, Chinese and Korean coastal waters, recurrent blooms of a small, elongate Prorocentrum species have been observed in recent years. In previous studies, this species has been respectively identified as P. shikokuense, P. donghaiense and P. dentatum, despite morphological similarity and identical rDNA sequences. To resolve the confusion, morphological features, including the architectural details of the periflagellar area, were examined and ribosomal DNA (rDNA) sequences were obtained from specimens collected from the East China Sea and Korean coast, and a strain established in the waters off the Canary Islands of Spain. In addition, the descriptions of the three species and allied species were reviewed. Morphological observations and a phylogeny based on the SSU, ITS region and LSU rDNA sequences revealed that the previously confused species and our studied strains are conspecific and that the morphology of strains identified as P. dentatum in the phylogenetic trees does not coincide with P. dentatum sensu stricto. The confusion can be traced back to Dodge (1975, p. 116), who considered P. veloi, P. monacense and P. obtusidens as junior heterotypic synonyms of P. dentatum. However, Dodge's P. dentatum are closer to P. obtusidens sensu stricto, rather than P. dentatum sensu stricto. P. obtusidens sensu stricto can be distinguished from P. dentatum sensu stricto by its relatively small size, parallel sides towards the anterior and a blunt anterior extension on one side. This indicates that P. obtusidens should not be considered a synonym of P. dentatum sensu stricto. In addition, a comparison of the original descriptions of P. obtusidens and allied species allowed to conclude that small, elongate Prorocentrum from Japanese, Chinese and Korean coastal waters previously identified as P. shikokuense, P. donghaiense, P. dentatum sensu Yoo and Lee (1986) and the specimens studied herein, which share identical rDNA sequences, morphologically coincide with P. obtusidens. Therefore, it is proposed that P. shikokuense and P. donghaiense should be regarded as junior synonyms of P. obtusidens., (Copyright © 2019 Elsevier B.V. All rights reserved.)