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2.
Zootaxa ; 4486(1): 31-56, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30313764

RESUMO

The Asian monotypic genus Pararhabdophis Bourret, 1934 has long been known from a single holotype of the type species Pararhabdophis chapaensis Bourret, 1934 only. The limited available information hampered the identification of the natricine species. On the basis of eight newly collected specimens of P. chapaensis from the type locality in Sa Pa, Lao Cai Province, Vietnam and from Pingbian, Yunnan Province in southwestern China, the taxonomic position of the genus Pararhabdophis was re-evaluated using both morphological and molecular datasets for the first time. Pararhabdophis chapaensis is nested within the genus Hebius Thompson, 1913 with strong support, and morphologically indistinguishable from the latter genus. As a consequence, we herein synonymize the genus Pararhabdophis with Hebius and discuss about the existing paraphyly of some Hebius species. In addition we report Hebius chapaensis for the first time from China and provide redescription and natural history data of this poorly known species. To facilitate future taxonomic work, an identification key to all known natricine genera from China and Vietnam is also provided.


Assuntos
Colubridae , Filogenia , Animais , China , Lagartos , Vietnã
3.
Zootaxa ; 4483(2): 385-394, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30313795

RESUMO

A new species of the natricine snake genus Hebius Thompson, 1913 is described from Sichuan Province, Southwest China, based on a single male specimen. The new species is distinguished from its congeners found in China and adjacent regions by possessing the following combination of characters: 1) TL/SVL ratio 0.35; 2) three postoculars; 3) six temporals in formula 1/(1+1) +1+2; 4) eight supralabials, 4th and 5th in contact with the eye, 6th supralabial largest; 5) ten infralabials with the first five bordering the anterior chinshields; 6) 172 ventrals (plus two preventrals); 7) cloacal plate divided; 8) 90 divided subcaudals; 9) dorsal scales in 19-19-17 rows, all weakly keeled except the outer two; 10) reduction of dorsal scale rows from 19 to 17 at the position above ventral scale 99th; 11) reduction of the tail dorsal scales from 8 to 6 rows at the position above 18th subcaudal, and from 6 to 4 rows at the position above 37th subcaudal; 12) postorbital bones do not touch frontals, the parietal ridge weakly developed; the end of the supratemporal bones extending beyond the braincase; maxillary teeth 23-25, the last two enlarged, without diastema between them and the anterior teeth. This species is an evergreen forest dweller.


Assuntos
Colubridae , Lagartos , Distribuição Animal , Estruturas Animais , Animais , China , Ecossistema , Masculino
4.
Huan Jing Ke Xue ; 39(6): 2748-2755, 2018 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965631

RESUMO

Zirconium alginate/poly(N-isopropyl acrylamide) hydrogel beads with a semi-interpenetrating network (ZA/PNIPAM) were prepared by using the ionic crosslinking and radical polymerization method and investigated for phosphate removal from aqueous solutions. The effects on the adsorption performance of hydrogel beads, including initial pH, adsorbent dose, initial phosphate concentration, and co-existing anions, were evaluated systematically. Results showed that the ZA/PNIPAM could exhibit a maximum uptake capacity of phosphate at pH 2.The uptake capacity of the adsorbent increased with a decrease in the dose or an increase in the initial phosphate concentration. The presence of SO42- had a more negative effect on phosphate removal compared to Cl- and NO3-. The kinetics fitted a pseudo-second-order model and intraparticle diffusion model, suggesting the adsorption rate was mainly controlled by surface adsorption and diffusion into the interior of the hydrogel beads. The isotherm data could be described by the Freundlich model, indicating that the adsorption process was heterogeneous multilayer adsorption. The studies of FTIR, XPS, and zero point of charge with relevant adsorption data revealed that the phosphate adsorption mechanisms could be electrostatic attraction (physical adsorption) and ligand exchange reactions (chemical adsorption). After four cycles of regeneration, ZA/PNIPAM exhibited a stable uptake capacity, indicating favorable reusability.

5.
Am J Physiol Regul Integr Comp Physiol ; 313(2): R149-R157, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28566304

RESUMO

Patients with chronic kidney disease (CKD) commonly complain upper gastrointestinal (GI) symptoms, especially anorexia. Hemodialysis (HD) has been noted to improve GI symptoms; however, the underlying mechanisms are unclear. This study was designed 1) to study effects of HD on GI symptoms and gastric slow waves; and 2) to investigate possible roles of ghrelin and glucagon-like peptide-1 (GLP-1): the study recruited 13 healthy controls, 20 CKD patients without HD (CKD group), and 18 CKD patients with HD (HD group). Dyspeptic symptoms, autonomic functions, gastric slow waves, and plasma level of ghrelin and GLP-1 were analyzed. First, the CKD patients with HD showed markedly lower scores of anorexia (0.6 ± 0.2 vs. 3.2 ± 0.4, P < 0.001) compared with patients without HD. Second, the CKD group but not HD group showed a significant reduction (25.6%) in the percentage of normal gastric slow waves, compared with controls. Third, the CKD group exhibited a significantly lower ghrelin level compared with the HD group (26.8 ± 0.9 vs. 34.1 ± 2.3 ng/l, P < 0.02) and a higher GLP-1 level (29.4 ± 2.8 vs. 20.0 ± 2.1 pmol/l, P < 0.05) compared with controls. Moreover, the percentage of normal slow waves was positively correlated with ghrelin (r = 0.385, P = 0.019) but negatively correlated with GLP-1 (r = -0.558, P < 0.001) in all CKD patients. Hemodialysis improves upper GI symptoms and gastric slow waves in CKD patients. An increase in ghrelin and a decrease in GLP-1 might be involved in the HD-induced improvement in gastric slow waves.


Assuntos
Hormônios Gastrointestinais/metabolismo , Motilina/metabolismo , Complexo Mioelétrico Migratório , Diálise Renal , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/terapia , Adulto , Idoso , Feminino , Trânsito Gastrointestinal , Grelina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estômago/fisiopatologia , Resultado do Tratamento
6.
Zootaxa ; 4020(2): 390-6, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26624106

RESUMO

Plagiopholis unipostocularis Zhao, Jiang & Huang, 1978 is a small snake endemic to Yunnan, southern China. Its validity is still controversial and unresolved. Based on extensive sampling in Yunnan, we conducted morphological comparison and molecular phylogenetics on the unidentified specimens of Plagiopholis from Yunnan. Based on a combination of morphological comparison and molecular phylogeny, the newly collected specimens could be identified as P. blakewayi. While some specimens exhibit one or more diagnostics of P. unipostocularis, and some characteristics are intermediate between that of Plagiopholis unipostocularis and P. blakewayi. Thus morphological continuities between two species uncovered P. unipostocularis is a synonymy of P. blakewayi, and the diagnostics of this species was revised accordingly.


Assuntos
Colubridae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , China , Colubridae/anatomia & histologia , Colubridae/genética , Colubridae/crescimento & desenvolvimento , Feminino , Masculino , Tamanho do Órgão , Filogenia
7.
Dongwuxue Yanjiu ; 35(4): 350-2, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25017757

RESUMO

Three Asian green pit vipers were collected in August 2013 during a field trip in Fanjin Mt. National Conservation Area, Guizhou. These specimens were identified as Sinovipera sichuanensis, based on subsequent examination and comparison. This is a new record of the genus Sinovipera and S. sichuanensis in Guizhou, and the first time that male specimens have been collected in the field.


Assuntos
Viperidae/fisiologia , Animais , Demografia , Feminino , Masculino
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