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1.
J Fish Biol ; 76(5): 1173-89, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20409169

RESUMO

Mitochondrial DNA cytochrome b sequences (1140 bp) in 61 specimens of Chinese spiny loach Cobitis sinensis from 12 drainages in Taiwan were identified as two major clades, exhibiting a southern and a northern distribution, north of TzengWen and south of TzengWen (including TzengWen), respectively. The divergence time between these two phylogroups was estimated at 7.34-9.06 million years before present (B.P.), but these two phylogroups were formed c. 3.41-4.23 and 2.22-2.75 M B.P., respectively. Moreover, geological events have been recalculated that Taiwan Island emerged above sea level at an estimate of c. 4-5 M B.P., and quickly became its present shape at c. 2 M B.P. through mountain building. These results suggest that these two major clades of C. sinensis in Taiwan might originate from two different continental populations, since the island's initial isolation in the Pliocene. Within southern Taiwan, the initial colonization was hypothesized to be in KaoPing River, followed by its northward dispersal. The high divergence between KaoPing and TzengWen was influenced by glaciations and landforms. Within north Taiwan, the colonization was from the Miaoli Plateau through western Taiwan to north-eastern and northern Taiwan. This dispersal pattern is concordant with the previously proposed hypothesis. Apparently, both geological and phylogeographic evidence suggested that river capture of the upper Takia River by the LanYang River promoted range expansion in freshwater fishes and also indicated that the Central Range within Taiwan did not act as a barrier to the dispersal of C. sinensis.


Assuntos
Cipriniformes/genética , DNA Mitocondrial/genética , Evolução Molecular , Genética Populacional , Filogenia , Animais , Teorema de Bayes , Citocromos b/genética , Variação Genética , Geografia , Funções Verossimilhança , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA , Taiwan
2.
BMC Evol Biol ; 9: 161, 2009 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-19589178

RESUMO

BACKGROUND: This study addresses the apportionment of genetic diversity between Cycas revoluta and C. taitungensis, species that constitute the section Asiorientales and represent a unique, basal lineage of the Laurasian genus Cycas. Fossil evidence indicates divergence of the section from the rest of Cycas at least 30 million years ago. Geographically, C. taitungensis is limited to Taiwan whereas C. revoluta is found in the Ryukyu Archipelago and on mainland China. RESULTS: The phylogenies of ribosomal ITS region of mtDNA and the intergenic spacer between atpB and rbcL genes of cpDNA were reconstructed. Phylogenetic analyses revealed paraphyly of both loci in the two species and also in the section Asiorientales. The lack of reciprocal monophyly between these long isolated sections is likely due to persistent shared ancestral polymorphisms. Molecular dating estimated that mt- and cp DNA lineages coalesced to the most recent common ancestors (TMRCA) about 327 (mt) and 204 MYA (cp), corresponding with the divergence of cycad sections in the Mesozoic. CONCLUSION: Fates of newly derived mutations of cycads follow Klopfstein et al.'s surfing model where the majority of new mutations do not spread geographically and remain at low frequencies or are eventually lost by genetic drift. Only successful 'surfing mutations' reach very high frequencies and occupy a large portion of a species range. These mutations exist as dominant cytotypes across populations and species. Geographical subdivision is lacking in both species, even though recurrent gene flow by both pollen and seed is severely limited. In total, the contrasting levels between historical and ongoing gene flow, large population sizes, a long lifespan, and slow mutation rates in both organelle DNAs have all likely contributed to the unusually long duration of paraphyly in cycads.


Assuntos
Cycas/genética , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Evolução Molecular , Polimorfismo Genético , China , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Genes de Plantas , Genética Populacional , Geografia , Haplótipos , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
3.
Br J Dermatol ; 161(2): 273-80, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19438447

RESUMO

BACKGROUND: The treatment of vitiligo remains a challenge for clinical dermatologists. We have previously shown that the helium-neon laser (He-Ne laser, 632.8 nm) is a therapeutic option for treatment of this depigmentary disorder. OBJECTIVES: Addressing the intricate interactions between melanocytes, the most important cellular component in the repigmentation scheme of vitiligo, and their innate extracellular matrix collagen type IV, the current study aimed to elucidate the effects of the He-Ne laser on melanocytes. METHODS: Cultured melanocytes were irradiated with the He-Ne laser. Relevant biological parameters including cell attachment, locomotion and growth were evaluated. In addition, the potentially involved molecular pathways were also determined. RESULTS: Our results show that in addition to suppressing mobility but increasing attachment to type IV collagen, the He-Ne laser stimulates melanocyte proliferation through enhanced alpha2beta1 integrin expression. The expression of phosphorylated cyclic-AMP response element binding protein (CREB), an important regulator of melanocyte growth, was also upregulated by He-Ne laser treatment. Using a specific mitochondrial uncoupling agent [carbonyl cyanide m-chlorophenyl-hydrazone (CCCP)], the proliferative effect of the He-Ne laser on melanocytes was abolished and suppression of melanocyte growth was noted. CONCLUSIONS: In summary, we have demonstrated that the He-Ne laser imparts a growth stimulatory effect on functional melanocytes via mitochondria-related pathways and proposed that other minor pathways including DNA damage may also be inflicted by laser treatment on irradiated cells. More importantly, we have completed the repigmentation scheme of vitiligo brought about by He-Ne laser light in vitro and provided a solid theoretical basis regarding how the He-Ne laser induces recovery of vitiligo in vivo.


Assuntos
Colágeno Tipo IV/efeitos da radiação , Expressão Gênica/efeitos da radiação , Lasers de Gás , Terapia com Luz de Baixa Intensidade , Melanócitos/efeitos da radiação , Vitiligo/radioterapia , Adulto , Western Blotting , Adesão Celular , Proliferação de Células , Colágeno Tipo IV/metabolismo , Humanos , Melanócitos/metabolismo , Neônio , Vitiligo/genética , Vitiligo/metabolismo
4.
Transplant Proc ; 50(9): 2756-2758, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401391

RESUMO

Everolimus (EVR) can be used with calcineurin inhibitors to reduce the risk of renal dysfunction, with similar immunosuppressive effect. In this study, we compared renal function after heart transplantation (HT) under EVR with cyclosporine (CSA) or tacrolimus (TAC). Between 2004 and 2014, EVR with CSA or TAC was used in 117 HT at the National Taiwan University Hospital. After HT, all patients received corticosteroid, EVR (C0 target 3-8 ng/mL) and CSA (C0 blood level 100-200 ng/mL), or TAC (Co blood level 5-10 ng/mL). Renal function was evaluated before HT, every month after HT for up to 1 year, and then every 3 months for up to 2 years. Blood-drug levels of EVR, CSA, and TAC were also monitored simultaneously with renal function. The estimated mean glomerular filtration rate (eGFR) was 76.5 mL/min/1.73 m2 before HT. After HT, the eGFR was 64 mL/min/1.73 m2 at the third month, and 64 mL/min/1.73 m2 at the end of first year. The difference was significant between pre-HT and post-HT (P = .00) during the first year. No significant differences were noted between the CSA and TAC groups. Careful monitoring of blood-drug level and renal function is crucial after heart transplantation. It is concluded that under close monitoring blood-drug level and renal function, it is possible to reach acceptable postoperative renal function with no difference of renal function between EVR plus CSA and EVR plus TAC.


Assuntos
Ciclosporina/efeitos adversos , Everolimo/efeitos adversos , Transplante de Coração/métodos , Imunossupressores/efeitos adversos , Insuficiência Renal/induzido quimicamente , Tacrolimo/efeitos adversos , Adulto , Inibidores de Calcineurina/efeitos adversos , Quimioterapia Combinada , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/epidemiologia , Taiwan
5.
Transplant Proc ; 50(9): 2738-2741, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401387

RESUMO

BACKGROUND: Ensuring careful selection of heart transplant recipients with pretransplant malignancies (PTM) has been suggested in several retrospective studies. However, cancer survival rates continue to increase and we still lack outcomes data on PTM patients who have undergone heart transplantation (HT) within the Asian region. Herein we report pretransplant characteristics and outcomes among PTM patients with HT. METHODS: A total of 354 patients underwent HT from January 2004 to January 2016. Eight of these patients had a history malignancy that was being treated before transplantation. Posttransplant outcomes and clinical characteristics were collected and possible prognostic factors analyzed. RESULTS: The median age of the patients with a preexisting malignancy was 60 years. The PTM group included 5 males and 3 females, with a median duration of follow-up of 43 months. In this group there were 2 patients with lymphoma after chemotherapy, 1 with colon cancer postoperatively, and 1 was on chemotherapy. In the other 4 patients, nasopharyngeal cancer, thyroid cancer, breast cancer, and endometrial cancer were identified, and each had undergone treatment. Only 1 premalignancy patient, with nasopharyngeal cancer, had disease recurrence. The 5-year overall survival of these patients was 50.0 ± 17.7%, but 5-year survival for those without PTM was 68.7 ± 2.0%. CONCLUSION: PTM was 2.3% in our cohort. PTM is associated with an increased risk of all-cause mortality. Thus, our findings suggest careful consideration when selecting PTM patients for HT.


Assuntos
Transplante de Coração/mortalidade , Neoplasias/complicações , Neoplasias/mortalidade , Adulto , Idoso , Criança , Estudos de Coortes , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
6.
Clin Microbiol Infect ; 18(7): E232-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22448875

RESUMO

Taiwan CDC investigated four cases of recurrent imported vivax malaria during 2003-2010. Molecular genotyping results and the lack of inter-episodes travel history indicated that two of the patients, who acquired vivax malaria in Indonesia and the Solomon Islands, respectively, suffered relapses after an interval of 3-4 months, despite completing standard-dose primaquine therapy (30 mg/day for 14 days) for the first episode. Treatment with a higher dose of primaquine (60 mg/day for 14 days) prevented further relapse in both patients. This finding calls for further monitoring of the therapeutic efficacy of primaquine in treating Plasmodium vivax acquired in southeast Asia and Oceania.


Assuntos
Antimaláricos/administração & dosagem , Malária Vivax/tratamento farmacológico , Plasmodium vivax/isolamento & purificação , Primaquina/administração & dosagem , Adulto , DNA de Protozoário/genética , Genótipo , Humanos , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Oceania , Plasmodium vivax/classificação , Plasmodium vivax/genética , Recidiva , Taiwan , Viagem
7.
Mol Ecol ; 15(3): 765-79, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16499701

RESUMO

Species whose geographical distribution encompasses both mainland and island populations provide an ideal system for examining isolation and genetic divergence. In this study, paternally transmitted chloroplast DNA (cpDNA) and maternally transmitted mitochondrial DNA (mtDNA) were used to estimate population structure and phylogeography of Pinus luchuensis, a species found in eastern China (ssp. hwangshanensis), Taiwan (ssp. taiwanensis), and the Ryukyu Archipelago (ssp. luchuensis). Gene genealogies of both mtDNA and cpDNA reveal two major lineages. Molecular dating indicates that these lineages diverged before the colonization of P. luchuensis subspecies in Taiwan and the Ryukyu Archipelago. Both mtDNA and cpDNA show a lack of correspondence between molecular phylogeny and subspecies designation. Phylogeographical analysis suggests that paraphyly of the subspecies is the result of recent divergence rather than secondary contacts. In spite of the short divergence history of P. luchuensis on islands, the island populations show the same degree of genetic divergence as mainland populations. Low levels of genetic diversity in the mainland ssp. hwangshanensis suggest demographic bottlenecks. In contrast, the high heterogeneity of genetic composition for island populations is likely to be associated with a history of multiple colonization from the mainland. The spatial apportionment of organelle DNA polymorphisms is consistent with a pattern of stepwise colonization on island populations.


Assuntos
Variação Genética , Filogenia , Pinus/genética , China , DNA de Cloroplastos/análise , DNA de Cloroplastos/genética , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Geografia , Dados de Sequência Molecular , Análise de Sequência de DNA , Taiwan
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