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1.
Zootaxa ; 5406(4): 535-550, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38480130

ABSTRACT

A new species of the genus Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Xiangxi River, Shennongjia Forestry District, Hubei Province, China, is described on the basis of an integrative approach, involving morphology, and molecular systematics. The new species Dugesia saccaria A-T. Wang & Sluys, sp. nov. is characterized by the following features: a dumb-bell-shaped, muscularized hump located just anterior to the knee-shaped bend in the bursal canal; a ventrally displaced ejaculatory duct, which, however, opens terminally through the dorsal portion of the blunt tip of the penis papilla; a ventrally located seminal vesicle, giving rise to a vertically running duct that eventually curves downwards to communicate with the ejaculatory duct via a small diaphragm; oviducts opening asymmetrically into the dorsal portion of the common atrium and at the knee-shaped part of the bursal canal. The phylogenetic position of the new species was determined using four molecular markers (18S rDNA; ITS-1; 28S rDNA; COI), which suggested that it groups with other species of Dugesia from the Australasian and Oriental biogeographical regions.


Subject(s)
Planarians , Male , Animals , Planarians/anatomy & histology , Phylogeny , Penis , China , DNA, Ribosomal
2.
Zoolog Sci ; 39(2): 206-214, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35380192

ABSTRACT

A new species of Dalyelliidae, Gieysztoria pellucida Wang and You, is described based on material collected in southern China through an integrative approach combining morphological, histological, and molecular (18S and 28S rDNA) data. Gieysztoria pellucida sp. nov. is morphologically characterized by a fan-shaped (about 270° when pressed) stylet, consisting of 13 similar distal spines and a broad girdle without fenestrae region. This stylet is distinct from that of any other similar species in the Aequales group to which this species belongs. In addition, specimens identifiable as Gieysztoria garudae Van Steenkiste, Van Mulken, and Artois, 2012 were discovered from the same location as G. pellucida sp. nov. Gieysztoria garudae has previously been known only from India; the present study thus represents the first record of the species from China.


Subject(s)
Platyhelminths , Animals , China , DNA, Ribosomal , Fresh Water , India , Phylogeny
3.
Zootaxa ; 4808(3): zootaxa.4808.3.13, 2020 Jul 03.
Article in English | MEDLINE | ID: mdl-33055972

ABSTRACT

Two new species of the new genus Pseudorogneda of Polycystididae were discovered in a brackish environment from Southern China. Pseudorogneda sinensis n. gen. n. sp., is distinguished by a semicircular double-walled prostate stylet type II that tapers in diameter from proximal to distal with a proximal-to-distal fold, and an inner wall with a funnel-shaped base originating at the midpoint of the outer wall; its flattened tubular prostate stylet type IV exhibits a horn-like base and a proximal-to-distal folded structure on its wall. For Pseudorogneda shenda n. gen. n. sp., its crescent-shaped prostate stylet type II is double-walled and the inner wall has a funnel-shaped base that starts at the proximal 2/3 position of the outer stylet and is fused with the outer stylet to form a sharp distal end; its tubular and slightly-curved prostate stylet type IV exhibits a slit and a distal fold. Phylogenetic analysis of 18S rDNA and 28S rDNA sequences shows that the two novel species are clustered to form an independent clade from other genera, which is consistent with morphological comparison in the establishment of two new species in a new genus.


Subject(s)
Platyhelminths , Animals , China , DNA, Ribosomal , Male , Phylogeny
4.
Zootaxa ; 4568(1): zootaxa.4568.1.9, 2019 Mar 19.
Article in English | MEDLINE | ID: mdl-31715876

ABSTRACT

Two new species of flatworm, collected from a beach at eastern Shenzhen, China, were studied through an integrative approach by combining morphological, histological, histochemical (acetylcholinesterase, AChE), and molecular (18S r- DNA) data. These species belong to two genera of marine triclads, previously unrecorded from China, viz. Nerpa Marcus, 1948 and Paucumara Sluys, 1989.        Nerpa fistulata Wang Chen, sp. nov. is characterized by: transparent body; principally pentamerous intestine with three distinct commissures; two very large, prepharyngeal testis follicles; a semi-circular lens in each eye cup; a penis papilla provided with a chitinized, pointed stylet; lateral bursae communicating with the oviduct and opening ventrally to the exterior via a duct. Phylogenetically N. fistulata groups with one member of the family Bdellouridae. This new, Chinese species of Nerpa introduces a major geographic disjunction, as the type species N. evelinae was described from the bay of Santos, Brazil, so that the genus is now known from both Atlantic as well as Pacific coasts.        The species Paucumara falcata Wang Li, sp. nov. is characterized by: three distinct pale yellow transverse pigmentation bands on its dorsal side, between which some snowflake-like specks are randomly distributed, and a brown transverse band anteriorly to the eyes; 8-11 testicular follicles on either side of the body, the follicles extending from immediately behind the ovaries to half-way along the pharyngeal pocket; a musculo-parenchymatic organ with a sclerotic, curved tip projecting from the anterior wall of the male atrium, ventrally to the root of the penis papilla. Phylogenetically P. falcata groups with its congener P. trigonocephala, with the genus Paucumara forming the sister taxon of the genus Ectoplana. Comparison of the nerve structure of P. falcata, as revealed by AChE histochemistry, with that of eight other species of triclad suggested that the nervous system of marine planarians is simpler than that of species of freshwater planarians, but revealed also that the nerve structure is rather variable among species.        The copulatory position exhibited by two partners in Paucumara falcata is remarkable in that they intertwine, with their heads pointing downwards and the tails pointing upwards, the entire process lasting about 10 min. Such a copulatory position has never before been reported for triclad flatworms.


Subject(s)
Planarians , Animals , Brazil , China , Male , Nervous System , Phylogeny
5.
Int J Syst Evol Microbiol ; 68(7): 2158-2164, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29762105

ABSTRACT

A Gram-stain-negative, non-flagellated, short rod-shaped bacterium, designated XY-R6T, was isolated from the rhizosphere soil of a mangrove plant, Kandelia candel (L.) Druce, in Mai Po Nature Reserve, Hong Kong. Growth of strain XY-R6T was observed at pH 5.0-9.5 (optimum 6.5-8.0), between 8 and 42 °C (optimum 28-34 °C), and in the presence of 0-9.5 % (w/v) NaCl (optimum 1-4 %). The predominant isoprenoid quinone was ubiquinone-10. The major fatty acids were summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c) (55.61 %), C19 : 0cycloω8c (21.59 %) and C16 : 0 (11.24 %). The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, aminolipid, phosphatidylcholine and diphosphatidylglycerol. The genomic DNA G+C content of strain XY-R6T was 69.3 mol%. Phylogenetic analyses, based on 16S rRNA gene sequences, revealed that strain XY-R6T belonged to the family Rhodobacteraceae of the class Alphaproteobacteria and formed a distinct lineage, showing the highest gene sequence similarities to the members of genus Wenxinia(94.5-94.3 %), followed by the genera Profundibacterium (94.3 %), Defluviimonas(93.8-92.5 %), Oceanicola (93.8 %) and Cereibacter (93.7 %). Similarities to other genera within the family Rhodobacteraceae were below 94.0 %. Based on comprehensive phenotypic, phylogenetic and chemotaxonomic characterization, it is indicated that strain XY-R6T represents a novel species of a new genus in the family Rhodobacteraceae, for which the name Kandeliimicrobium roseum gen. nov., sp. nov. is proposed, with XY-R6T (=MCCC 1K01498T=KCTC 52266T=DSM 104294T) as the type strain.


Subject(s)
Phylogeny , Rhizophoraceae , Rhizosphere , Rhodobacteraceae/classification , Soil Microbiology , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Hong Kong , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Rhodobacteraceae/genetics , Rhodobacteraceae/isolation & purification , Sequence Analysis, DNA , Ubiquinone/chemistry
7.
Article in English | MEDLINE | ID: mdl-20059392

ABSTRACT

Aims: Fibrodysplasia ossificans progressiva (FOP) is a rare and severely disabling autosomal dominant disorder characterized by congenital malformations of the great toes and progressive postnatal heterotopic ossification. A point mutation in the activin receptor IA (ACVR1) gene is the cause of FOP. Most of the reported cases of FOP are sporadic and caused by de novo mutations; however, some rare cases can also result from parental germline mosaicism associated with a greater risk of recurrence in successive pregnancies. Therefore, once the pathogenic mutation has been identified in the proband, it is relative cheaper and important to perform prenatal diagnostic tests to exclude the recurrence risk of FOP in subsequent pregnancies. In this study, we first investigated the mutation in the ACVR1 gene in a Chinese FOP patient and then performed prenatal tests to exclude the risk of recurrence in the patient's unborn sibling. Methods: A couple visited our clinic with their 4-year-old son, who was clinically diagnosed with FOP, for genetic counseling. Genetic testing was performed by amplifying all the nine exons of the ACVR1 gene using the conventional polymerase chain reaction. Further, DNA sequencing was used to determine the mutation based on the results of a mutation screening using denaturing high-performance liquid chromatography. Subsequently, a prenatal test was performed using the same technique as that used for the proband. Results: A recurrent single nucleotide mutation c.617 G>A (R206H) of the ACVR1 gene was identified in the patient; however, both the parents had a normal ACVR1 gene. Prenatal tests showed that the fetus did not carry the pathogenic mutation. Conclusion: The results confirmed that a recurrent single nucleotide mutation c.617 G>A (R206H) was the genetic cause of FOP and explored the utility of prenatal testing in excluding the risk of recurrence in the successive pregnancy.

8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(5): 780-3, 787, 2008 Sep.
Article in Chinese | MEDLINE | ID: mdl-19024313

ABSTRACT

OBJECTIVE: To identify the interactions of susceptive genes with related to the genetic polymorphism of metabolism enzymes (CYP1A1, GSTT1 and GSTM1) and their impacts on the risk of breast cancer; and to test the feasibility of using Multifactor Dimensionality Reduction (MDR) model in analyzing gene-gene interactions. METHODS: A paired case-control study, matched by age and menstruate state, was conducted. From December 2003 to September 2004, 78 pairs of people with and without breast cancers were investigated. The variant genotypes of CYP1A1 Msp I and GSTT1/M1 were identified by PCR-RFLP and multiplex PCR assays. The gene-gene interactions were analyzed with the MDR model. Based on the result of the MDR model, a conditional logistic regression model was constructed as the final cause-effect interpretative model. RESULTS: The interaction between CYP1A1 Msp I variant genotype (vv) and GSTT1 null genotype gave the best MDR model with statistical significance (Sign Test, P = 0.05). The model Testing Balance Accuracy was 0. 5920. The Cross-Validation consistency was 10/10. The final conditional logistic regression based on the MDR model showed that passive smoking, abortion and gene-gene interaction were risks of breast cancers, with an OR (95% confidence interval) of 12.234 (1.7459-85.7279), 4.554 (1.3250-15.6507) and 9.597 (1.5783-58.3599), respectively. CONCLUSION: The MDR model may be an effective method for estimating risks of breast cancers due to gene-gene and gene-environment interactions. The gene-gene interaction with related to the genetic polymorphism of metabolism enzymes (CYP1A1 and GSTT1) may increase the risk of breast cancer by disturbing the metabolism of estrogen.


Subject(s)
Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Genetic Predisposition to Disease/genetics , Models, Genetic , Polymorphism, Genetic , Adult , Aged , Breast Neoplasms/metabolism , Case-Control Studies , Cytochrome P-450 CYP1A1/genetics , Female , Genotype , Glutathione Transferase/genetics , Humans , Logistic Models , Matched-Pair Analysis , Middle Aged , Risk Assessment
9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 38(4): 697-700, 2007 Jul.
Article in Chinese | MEDLINE | ID: mdl-17718445

ABSTRACT

OBJECTIVE: To determine the prevalence of dental caries in children with cleft lip and Palate. METHODS: A cross-sectional study was undertaken in 380 children with cleft lip and Palate and 339 children without cleft. Dental caries were measured with decayed-missing-filed-teeth index (DMFT/dmft) and the decayed-missing-filed-surface index (DMFS/dmfs). A questionnaire survey about the socio-economic conditions and lifestyles of the children's families was undertaken in the parents of the children. RESULTS: (1) The children with cleft Palates had a higher prevalence of caries and greater DMFT(S) and dmft(s) scores than the children without cleft (P < 0.05), except for those of 3 to 5 years old. (2) For the children of 3 to 5 years old, those with cleft lip and palate had significantly more caries than those with only a cleft lip or a cleft lip and alveolus (P < 0.05). The children who had surgical repairs had lower dmft(s) than those who had not (P < 0.05). CONCLUSION: (2) Chinese children with oral cleft have more dental caries than the children without cleft. (2) Children with cleft lip and palate have higher levels of dental caries than those with cleft lip alone. The children who had surgical repairs have less dental caries.


Subject(s)
Cleft Lip/complications , Cleft Palate/complications , Dental Caries/complications , Dental Caries/epidemiology , Adolescent , Adult , Case-Control Studies , Child , Child, Preschool , China/epidemiology , Cleft Lip/surgery , Cleft Palate/surgery , Cross-Sectional Studies , Humans , Male , Young Adult
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(2): 123-6, 2007 Feb.
Article in Chinese | MEDLINE | ID: mdl-17649679

ABSTRACT

OBJECTIVE: To study the contents of organochlorine pesticides in human bodies and residues in serum of populations with non-occupational exposure as well as to study the relationship between organochlorine pesticides in foodstuff and residues levels in serum. METHODS: A cross-section study was conducted. 107 men and 142 women who were all healthy and living in the communities were investigated from Mar. 2004 to Jul. 2004. Level of daily food exposure was estimated through questionnaires while DDTs and HCHs serum levels were detected by EC-ECD. The relationship between organochlorine pesticides contents in foods and residues in serum were analyzed by ridge regression. RESULTS: Fresh fish was positively correlated to men's serum level of beta-HCH and p,p'-DDT (beta = 0.1266 and beta = 0.0595) while vegetables and fruits were negatively correlated to women's serum level of beta-HCH (beta = -0.1066). Soybean was negatively correlated to women's serum level of p,p'-DDE and p,p'-DDT (beta = -0.0965 and 3 = -0.0581). Alcohol consumption was negatively correlated to men's serum level of beta-HCH and p,p'-DDE and women's serum level of p,p'-DDE (beta = -0.1315, beta = -0.1599 and P = -0.1128).Salted meat was negatively correlated to men's serum level of beta-HCH and p, p'-DDT (P = -0. 066 and P = - 0.0569). CONCLUSION: In this study, fresh fish might increase the body burden of organochlorine pesticides and residues while alcohol might promote the excretion of organochlorine pesticides. Pickled meat and vegetal foodstuff might contain low-level of organochlorine pesticides and residues.


Subject(s)
Environmental Exposure , Hydrocarbons, Chlorinated/blood , Pesticide Residues/blood , China , Diet , Food Contamination , Humans , Seafood , Vegetables
11.
Yi Chuan Xue Bao ; 31(10): 1072-81, 2004 Oct.
Article in Chinese | MEDLINE | ID: mdl-15552041

ABSTRACT

Two types of complementary DNAs (cDNA) encoding the precursor of salmon gonadotropin-releasing hormone (sGnRH, [Trp7, Leu8] GnRH) are cloned and sequenced from common carp brain using rapid amplification of cDNA ends (RACE). The two cDNAs are referred to sGnRH cDNA1 and cDNA2, and the full-length fragment of cDNA1 and cDNA2 were 393 and 478 bp, respectively. Two sGnRH cDNAs contain an open reading frame of 285 bp, which encodes the sGnRH precursor including 94 amino acid residues. The sGnRH precursors consist of a signal peptide, sGnRH decapeptide and a GnRH-associated peptide (GAP) which is linked by the processing site (Gly-Lys-Arg). Two different sGnRH genes are characterized by intron trapping, and they share a similar structure composed of four exons and three introns. The nucleotide sequences identity of intron 1, intron 2 and intron 3 in sGnRH gene1 and gene2 are 71.1, 76. 1 and 88.0%, respectively. The basic structure and encoding architecture of sGnRH cDNAs and genes are similar with the reported GnRH. It is presumed that all the GnRH variants may evolve from a common ancestral molecular. Southern blot results confirm further the conclusion that there are two differential sGnRH genes in common carp genome. The results of reverse transcription-polymerase chain reaction (RT-PCR) assaying show that the two sGnRH genes co-express in the dissected brain regions, pituitary and ovary with the exception of expression of sGnRH genes in testis. According to the co-existence of two sGnRH genes in distinct brain regions,pituitary and ovary, it is presumed that sGnRH plays an important role in the regulation of hypothalamic-pituitary-gonadal (HPG) axis,and that sGnRH also operates as the neuromodulator, autocrine and/or paracrine regulator.


Subject(s)
Carps/genetics , Gonadotropin-Releasing Hormone/analogs & derivatives , Gonadotropin-Releasing Hormone/genetics , Protein Precursors/genetics , Amino Acid Sequence , Animals , Base Sequence , Blotting, Southern , Brain/metabolism , Cloning, Molecular , Female , Gonadotropin-Releasing Hormone/chemistry , Male , Molecular Sequence Data , Ovary/metabolism , Pituitary Gland/metabolism , Polymerase Chain Reaction , Protein Precursors/chemistry
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