The complete chloroplast genome of Eastern Asian fern Bolbitis laxireticulata (Dryopteridaceae)

Bolbitis laxireticulata is a potential ornamental plant, which is restricted to eastern Asia. Here, we sequenced the complete chloroplast (cp) genome of B. laxireticulata and constructed a phylogenetic cp tree of Dryopteridaceae to study their relationships. The cp genome of B. laxireticulata is 153,093 bp in length, being made up of large single-copy (LSC, 83,169 bp), small single-copy (SSC, 21,538 bp), and a pair of region inverted repeats (IRs, 24,193 bp). It has 124 genes including 83 protein-coding genes, 33 tRNA genes, and eight rRNA genes. With the maximum-likelihood tree indicating, B. laxireticulata is more closely related to B. subcordata.

Phylogeny, character evolution, and biogeography of the fern genus Bolbitis (Dryopteridaceae)

Bolbitis is a pantropical fern genus of Dryopteridaceae with ca. 80 species mainly in tropical Asia. Earlier studies confirmed the monophyly of Bolbitis when Mickelia is excluded and identified three major clades in Bolbitis. However, earlier studies are based on relatively small sampling and the majority of Asian species are not sampled. In this study, DNA sequences of three plastid markers of 169 accessions representing ca. 68 (85 % of total) species of Bolbitis in nine out of the 10 series recognized by Hennipman (1977), and 54 accessions representing the five remaining bolbitidoid genera are used to infer a global phylogeny with a focus on Asian species. The major results include: (1) Bolbitis is strongly supported as monophyletic; (2) species of Bolbitis are resolved into four major clades and their relationships are: the Malagasy/Mascarene clade is sister to the rest, followed by the African clade which is sister to the American clade + the Asian clade; (3) six well-supported subclades are identified in the most speciose Asian clade; (4) the free-veined Egenolfia is embedded in Bolbitis and is paraphyletic in relation to species with anastomosing venation; (5) three series sensu Hennipman (1977), B. ser. Alienae, B. ser. Egenolfianae, and B. ser. Heteroclitae, are paraphyletic or polyphyletic; (6) evolution of six morphological characters is analyzed and free venation is found to have evolved from anastomosing venation and reversed to free venation in Bolbitis; and (7) biogeographical implications are drawn and it is shown that a single recent dispersal from Asia resulted in continental disjunction of closely related ferns of Bolbitis between Africa and America.

[Clinicopathological observation of 10 cases of salivary secretory carcinoma]

Objective: To investigate the clinical and pathological features of salivary secretory carcinoma (SSC). Methods: Ten cases of SSC confirmed in the Department of Pathology,Capital Medical University School of Stomatology from January 2014 to December 2021 were retrospectively included, including 5 males and 5 females, with a median age of 46.5 years. The microscopic morphology, immunophenotype, special staining and clinical follow-up of 10 cases of salivary secretory carcinoma were observed. Ten patients were tested with S-100, vimentin, mammaglobin, Dog-1, p63 and Ki-67, 9 cases with cytokeratin (CK) 8/18, 8 with CK7, 6 with calponin, 5 with smooth muscle actin (SMA) and GCDFP15, 4 with CK5/6 and 1 with SOX10. The ETV6-NTRK3 fusion gene was detected by fluorescence in situ hybridization. Results: Seven of the 10 SSC were located in the parotid gland and 3 were located in the cheeks. Histomorphology showed solid, papillary-cystic, follicular, microcystic, and macrocystic types. In 7 cases, tumor cells were dominated by single arrangement type, while certain mixed arrangements existed in some areas. The cytoplasm of the tumor cells was rich in eosinophilic, fine granular or vacuolar shapes, and clear cytoplasm was seen in 2 cases. The nuclei were mostly oval-shaped vesicular nuclei, with nucleoli in the center. Immunohistochemistry showed CK7 (8/8) positive, CK8/18 (9/9) positive, S-100 (10/10) positive, vimentin (5/10) positive, (4/10) partially positive and (1/10) less partially positive, mammaglobin (7/10) positive, (1/10) partially positive and (2/10) some individual cells positive, Dog-1 (10/10) negative, CK5/6 (4/4) negative, p63 (7/10) negative and (3/10) partially positive, SMA (5/5) negative, calponin (6/6) negative, and Ki-67 index was 5%-20%. Secretions of 5 cases showed periodic acid-Schiff (PAS) and PAS with diastase (PAS-D) staining positive. All 10 cases showed ETV6-NTRK3 fusion positive. Six cases were successfully followed up for 32-91 months, of which 2 cases recurred after 28 and 74 months and underwent surgical resection again. All cases followed up are alive and disease-free. Conclusions: The salivary secretory carcinoma is a rare low-grade malignant tumor. In certain cases, morphology is atypical and mammaglobin is immunohistochemically positive in only individual tumor cells. Therefore, the diagnosis should be supported with morphology, immunohistochemical staining, and molecular feature preferably.

Ceratopteris chunii and Ceratopteris chingii (Pteridaceae), two new diploid species from China, based on morphological, cytological, and molecular data

Understanding how natural hybridization and polyploidizations originate in plants requires identifying potential diploid ancestors. However, cryptic plant species are widespread, particularly in Ceratopteris (Pteridaceae). Identifying Ceratopteris cryptic species with different polyploidy levels is a challenge because Ceratopteris spp. exhibit high degrees of phenotypic plasticity. Here, two new cryptic species of Ceratopteris, Ceratopteris chunii and Ceratopteris chingii, are described and illustrated. Phylogenetic analyses reveal that each of the new species form a well-supported clade. C. chunii and C. chingii are similar to Ceratopteris gaudichaudii var. vulgaris and C. pteridoides, respectively, but distinct from their relatives in the stipe, basal pinna of the sterile leaf or subelliptic shape of the fertile leaf, as well as the spore surface. In addition, chromosome studies indicate that C. chunii and C. chingii are both diploid. These findings will help us further understand the origin of Ceratopteris polyploids in Asia.

Genome size evolution of the extant lycophytes and ferns

Ferns and lycophytes have remarkably large genomes. However, little is known about how their genome size evolved in fern lineages. To explore the origins and evolution of chromosome numbers and genome size in ferns, we used flow cytometry to measure the genomes of 240 species (255 samples) of extant ferns and lycophytes comprising 27 families and 72 genera, of which 228 species (242 samples) represent new reports. We analyzed correlations among genome size, spore size, chromosomal features, phylogeny, and habitat type preference within a phylogenetic framework. We also applied ANOVA and multinomial logistic regression analysis to preference of habitat type and genome size. Using the phylogeny, we conducted ancestral character reconstruction for habitat types and tested whether genome size changes simultaneously with shifts in habitat preference. We found that 2C values had weak phylogenetic signal, whereas the base number of chromosomes (x) had a strong phylogenetic signal. Furthermore, our analyses revealed a positive correlation between genome size and chromosome traits, indicating that the base number of chromosomes (x), chromosome size, and polyploidization may be primary contributors to genome expansion in ferns and lycophytes. Genome sizes in different habitat types varied significantly and were significantly correlated with habitat types; specifically, multinomial logistic regression indicated that species with larger 2C values were more likely to be epiphytes. Terrestrial habitat is inferred to be ancestral for both extant ferns and lycophytes, whereas transitions to other habitat types occurred as the major clades emerged. Shifts in habitat types appear be followed by periods of genomic stability. Based on these results, we inferred that habitat type changes and multiple whole-genome duplications have contributed to the formation of large genomes of ferns and their allies during their evolutionary history.

The complete chloroplast genome of Plateau herb Chesneya acaulis (Fabaceae)

Chesneya acaulis is a perennial herb, which restricts in Xizang (Tibet) of China, Afghanistan, and Pakistan. The complete chloroplast genome was sequenced using the Illumina Hiseq X-Ten platform. The genome lacks an inverted repeat (IR) region, containing 75 protein-coding genes, 29 tRNAs genes, and 4 rRNAs. The overall GC content is 34.6%. A phylogenetic tree based on the whole chloroplast genomes of 15 species indicated that C. acaulis had a close relationship with the genus Hedysarum, and it nested in the inverted repeat-lacking clade (IRLC), of the subfamily Papilionoideae (Leguminosae).

Dating Whole Genome Duplication in Ceratopteris thalictroides and Potential Adaptive Values of Retained Gene Duplicates

Whole-genome duplications (WGDs) are widespread in plants and frequently coincide with global climatic change events, such as the Cretaceous–Tertiary (KT) extinction event approximately 65 million years ago (mya). Ferns have larger genomes and higher chromosome numbers than seed plants, which likely resulted from multiple rounds of polyploidy. Here, we use diploid and triploid material from a model fern species, Ceratopteris thalictroides, for the detection of WGDs. High-quality RNA-seq data was used to infer the number of synonymous substitutions per synonymous site (Ks) between paralogs; Ks age distribution and absolute dating approach were used to determine the age of WGD events. Evidence of an ancient WGD event with a Ks peak value of approximately 1.2 was obtained for both samples; however, the Ks frequency distributions varied significantly. Importantly, we dated the WGD event at 51–53 mya, which coincides with the Paleocene-Eocene Thermal Maximum (PETM), when the Earth became warmer and wetter than any other period during the Cenozoic. Duplicate genes were preferentially retained for specific functions, such as environment response, further support that the duplicates may have promoted quick adaption to environmental changes and potentially resulted in evolutionary success, especially for pantropical species, such as C. thalictroides, which exhibits higher temperature tolerance.

A revised classification of Chinese Davalliaceae based on new evidence from molecular phylogenetics and morphological characteristics

Although the phylogenetic framework of Davalliaceae is known, the classification of Chinese Davalliaceae is still controversial. In this study, a molecular phylogenetic tree of 60 accessions, including 29 species produced in China, was constructed using five plastid DNA markers-atpB, atpB-rbcL, rbcL, rbcL-accD, and accD. New data on studied specimens, field investigations, and scanning electron microscopy analysis of leaf epidermis and spores were used to reclassify Chinese Davalliaceae. The taxonomic position of Davallia canariensis was confirmed based on new evidence and a new key to sections of Chinese Davalliaceae was proposed. The taxonomically controversial genus Paradavallodes was confirmed as a polyphyletic group, and it was assigned to Davallia sect. Trogostolon and Davallia sect. Davallodes. Further, species endemic to China were delimited, 21 species were admitted to six sections of Davallia, two new combinations were proposed, two new synonyms were defined and a new key to Chinese species of Davalliaceae was presented.

Re-establishment of species from synonymies based on DNA barcoding and phylogenetic analysis using Diplopterygium simulans (Gleicheniaceae) as an example

Because synonymy treatment traditionally relies on morphological judgments, it usually causes many problems in species delimitation and in the biodiversity catalogue. For example, Diplopterygium simulans, which belongs to the Gleicheniaceae family, has been considered to be synonymous with D. glaucum or D. giganteum based mainly on the morphology of its pinna rachis and blade. In the absence of molecular evidence, these revisions remain doubtful. DNA barcoding, which is considered to be a powerful method for species-level identification, was employed to assess the genetic distance among 9 members of the Diplopterygium genus. The results indicate that D. simulans is an independent species rather than a synonymy of D. glaucum or D. giganteum. Moreover, phylogenetic analysis uncovered the sisterhood of D. simulans and D. cantonense, which is supported by their geographical distributions and morphological traits. Incorrect synonymy treatment is prevalent in the characterization of biological diversity, and our study proposes a convenient and effective method for validating synonym treatments and discovering cryptic species.

Calcium metabolism and osteopathy in diabetes mellitus

To assess the changes of calcium metabolism and osteopathy in patients with diabetes. Serum Ca, P, AKP, PTH, CT, plasma fasting blood glucose (FBG) and HbA1 as well as X-ray film of the lumbar spine were measured in 30 diabetes patients; 11 were IDDM and 19 were NIDDM as compared to controls matched for age and sex. There were no significant differences in Ca, P, and CT values in serum between the IDDM and NIDDM patients and controls, whereas the serum levels of PTH and AKP were significant increased in IDDM patients. The incidence of osteoporosis which was shown by X-ray film in NIDDM patients was higher than in those of controls. No correlation between PTH value and osteoporosis or clinical control of diabetes was observed.

Identification of the relationship between Chinese Adiantum reniforme var. sinense and Canary Adiantum reniforme

BACKGROUND

There are different opinions about the relationship of two disjunctively distributed varieties Adiantum reniforme L. var. sinense Y.X.Lin and Adiantum reniforme L. Adiantum reniforme var. sinense is an endangered fern only distributed in a narrowed region of Chongqing city in China, while Adiantum reniforme var. reniforme just distributed in Canary Islands and Madeira off the north-western African coast. To verify the relationship of these two taxa, relative phylogenetic analyses, karyotype analyses, microscopic spore observations and morphological studies were performed in this study. Besides, divergence time between A. reniforme var. sinense and A. reniforme var. reniforme was estimated using GTR model according to a phylogeny tree constructed with the three cpDNA markers atpA, atpB, and rbcL.

RESULTS

Phylogenetic results and divergence time analyses--all individuals of A. reniforme var. sinense from 4 different populations (representing all biogeographic distributions) were clustered into one clade and all individuals of A. reniforme var. reniforme from 7 different populations (all biogeographic distributions are included) were clustered into another clade. The divergence between A. reniforme var. reniforme and A. reniforme var. sinense was estimated to be 4.94 (2.26-8.66) Myr. Based on karyotype analyses, A. reniforme var. reniforme was deduced to be hexaploidy with 2n = 180, X = 30, while A. reniforme var. sinense was known as tetraploidy. Microscopic spore observations suggested that surface ornamentation of A. reniforme var. reniforme is psilate, but that of A. reniforme var. sinense is rugate. Leaf blades of A. reniforme var. sinense are membranous and reniform and with several obvious concentric rings, and leaves of A. reniforme var. reniforme are pachyphyllous and coriaceous and are much rounder and similar to palm.

CONCLUSION

Adiantum reniforme var. sinense is an independent species rather than the variety of Adiantum reniforme var. reniforme. As a result, we approve Adiantum nelumboides X. C. Zhang, nom. & stat. nov. as a legal name instead of the former Adiantum reniforme var. sinense. China was determined to be the most probable evolution centre based on the results of phylogenetic analyses, divergence estimation, relative palaeogeography and palaeoclimate materials.

Mapping of HtNB, a gene conferring non-lesion resistance before heading to Exserohilum turcicum (Pass.), in a maize inbred line derived from the Indonesian variety Bramadi

The gene HtNB confers non-lesion resistance to the fungal pathogen Exserohilum turcicum in maize. To map this gene, we developed two F₂ populations, P111 (resistant line) x HuangZao 4 (susceptible line) and P111 x B73 (susceptible). HtNB was located on chromosome 8.07 bin, flanked by MAC216826-4 and umc2218 at distances of 3.3 and 3.4 cM, respectively. HtNB appears to be a new gene responsible for resistance to northern corn leaf blight. Functions of the genes in the region between umc1384 and umc2218 were predicted. In addition, several genes were found to be related to disease resistance, such as the genes encoding Ser/Thr protein kinase and protein-like leaf senescence.

Nucleotide sequence of a novel arylesterase gene from Vibro mimicus and characterization of the enzyme expressed in Escherichia coli

A gene coding for an arylesterase of Vibrio mimicus was cloned. Sequence determination reveals that the esterase gene has an open reading frame of 600 nucleotides which encodes a protein of M(r) 22,300. The deduced amino acid sequence contain a pentapeptide GDSLS (residues 27-31), which was also found in the phospholipid-cholesterol acyltransferase from Aeromonas hydrophila. Substitution of Ser-29 by alanine or cysteine in the cloned gene abolished the esterase activity in the tributyrin plate assay. On the other hand, the activity was not lost when Ser-31 was changed to alanine. The cloned gene was expressed in Escherichia coli, and the protein purified by a four-step procedure. The purified protein migrated on SDS/PAGE as a single band with an apparent M(r) of 22,100. This enzyme favoured the hydrolysis of several arylesters and was classified as an arylesterase (EC 3.1.1.2). N-Terminal analysis showed that Ser-20 was the first amino acid of the mature secreted protein, suggesting that the N-terminal 19 hydrophobic amino acids served as a signal peptide.

[An immunohistochemical study of keratin in adenoid cystic carcinoma of the salivary gland]

An immunohistochemical study of keratin was performed in forty-five cases of adenoid cystic carcinoma of salivary gland, the results were as follows: keratin was distributed in the duct system of normal salivary gland, but the acini were negative. The distribution of keratin were varied in different patterns of adenoid cystic carcinoma. The amount of synthesis of keratin was many in tubular type of high differentiated carcinoma, but, in basaloid solid type of low differentiated carcinoma, the synthesis of keratin was less; the content of keratin in cribriform and trabecular type was between the tubular type and basaloid solid type, and the former had more keratin than the latter.