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1.
Sci Rep ; 14(1): 2879, 2024 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-38311607

RESUMEN

Safety concerns, stemming from the presence of complex and unpredictable adulterants, permeate the entire industrial chain of traditional Chinese medicines (TCMs). The Notopterygii Rhizoma et Radix (NReR) from the Apiaceae family, commonly known as "Qiang-huo", is a widely used herbal medicine. The recent surge in its demand has given rise to a proliferation of counterfeit and substituted products in the market. Traditional identification presents inherent limitations, while DNA mini-barcoding, reliant on sequencing a short-standardized region, has received considerable attention as a new potential means to identify processed medicinal materials. In this study, we constructed a comprehensive Internal Transcribed Spacer 2 (ITS2) matrix encompassing genuine NReR and their commonly found adulterants for the first time. Leveraging this matrix, we conducted a thorough assessment of the genetic profiles and sources of NReR available in the Chinese herbal medicine market. Following established DNA barcoding protocols, the intra-specific genetic divergences within NReR species were found to be lower than the inter-specific genetic divergences from other species. Among the 120 samples that were successfully amplified, ITS2 exhibits an outstanding species-level identification efficiency of 100% when evaluated using both the BLASTN and neighbor-joining (NJ) tree methods. We concluded that ITS2 is a mini-barcode that has shown its potential and may become a universal mini-barcode for the quality control of "Qiang-huo", thereby ensuring the safety of clinical medication.


Asunto(s)
Medicamentos Herbarios Chinos , Código de Barras del ADN Taxonómico/métodos , ADN de Plantas/genética , ADN Espaciador Ribosómico/genética , Filogenia
2.
Cell Death Dis ; 14(1): 64, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36707511

RESUMEN

The pregnane X receptor (PXR) is an important regulator of hepatocellular carcinoma cellular resistance to antitumor drugs. Activation of PXR was modulated by the co-regulators. The target protein for the Xenopus plus end-directed kinesin-like protein (Xklp2) known as TPX2 that was previously considered as a tubulin regulator, also functions as the regulator of some transcription factors and pro-oncogenes in human malignances. However, the actions of TPX2 on PXR and HCC cells are still unclear. In the present study, our results demonstrate that the high expression of endogenous mRNA level of TPX2 not only correlated with the poor prognosis of advanced HCC patients who received sorafenib treatment but also with expression of PXR's downstream genes, cyp3a4 and/or mdr-1. Results from luciferase and real-time polymerase chain reaction (qPCR) showed that TPX2 leads to enhancement of the transcription factor activation of PXR. Protein-protein interactions between PXR and TPX2 were identified using co-immunoprecipitation. Mechanically, overexpression of TPX2 led to enhancement of PXR recruitment to its downstream gene cyp3a4's promoter region (the PXRE region) or enhancer region (the XREM region). Treatment of HCC cells with paclitaxel, a microtubule promoter, led to enhancement of the effects of TPX2, whereas vincristine, a microtubule depolymerizing agent caused a decrease in TPX2-associated effects. TPX2 was found to cause acceleration of the metabolism or clearance of sorafenib, a typical tyrosine kinase inhibitor (TKI) in HCC cells and in turn led to the resistance to sorafenib by HCC cells. By establishing novel actions of TXP2 on PXR in HCC cells, the results indicate that TPX2 could be considered a promising therapeutic target to enhance HCC cells sensitivity to antitumor drugs.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Receptor X de Pregnano/genética , Sorafenib/farmacología , Sorafenib/uso terapéutico , Factores de Transcripción/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Citocromo P-450 CYP3A/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Ciclo Celular/genética
3.
Front Oncol ; 12: 959151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35936699

RESUMEN

Background: Orthotopic liver transplantation (OLT) is a life-saving option for patients with hepatocellular carcinoma (HCC), but the expanded OLT criteria remain controversial. Objective: The study aimed to explore whether expanded OLT criteria can be applied to Chinese cirrhotic patients with HCC. Methods: This retrospective study analyzed risk factors for HCC recurrence and death and compared patients' tumor characteristics and outcomes in groups of Milan, "Up-to-seven," and Hangzhou criteria, and groups between met and unmet the combinative criteria of "Up-to-seven" and AFP of < 1000 ng/mL. Results: Among 153 patients who underwent OLT for HCC from January 2015 to February 2019 in 4 years of follow-up, 20 (13.1%) patients had HCC recurrence, and 11 (7.2%) had HCC-related death. Multivariate Cox regression analysis showed that preoperative alpha-fetoprotein (AFP) of > 1000 ng/mL (hazard ratio [HR]: 10.05, 95% confidence interval [CI]: 2.45-41.13, P = 0.001) was an independent risk factor for HCC recurrence and HCC-related death (HR: 6.63, 95%CI: 1.31-33.52, P = 0.022). Patients who did not meet Milan criteria but satisfied the "Up-to-seven" criteria had no differences in overall survival (OS) (P = 0.69) and disease-free survival (DFS) (P = 0.35) than patients who met the Milan criteria. The combination of "Up-to-seven" criteria and AFP of < 1000 ng/mL differed significantly (HR: 18.9; 95% CI: 4.0-89.2; P < 0.001). Patients with HCC who met the "Up-to-seven" criteria and AFP of < 1000 ng/mL (n = 121) had excellent survival with 4-year OS of 91.6% (P < 0.001) and DFS of 90.8% (P < 0.001), which is significantly better compared to the other group (n = 32) (OS of 67.5% and DFS of 46.5%) and patients who met the Milan criteria (n = 108, OS of 89.8%, DFS of 89.6%), allowing 28.9% (13/45) of patients who did not meet the Milan criteria to benefit from OLT. Conclusion: Chinese cirrhotic patients with HCC who met the combinative criteria of "Up-to-seven" and AFP of < 1000 ng/mL had better survival than those who met the Milan criteria, and these combinative criteria benefited more patients and may become a better option for OLT.

6.
PhytoKeys ; 182: 57-66, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34629927

RESUMEN

A new species, Cyclorhizapuana J. Zhou & Z.W. Liu (Apiaceae) from Sichuan Province of China, is described and illustrated here. Morphological comparisons with congeneric species revealed that it is distinguished by its slender habit, sparse annular scars, 4-pinnatisect leaf blade with ultimate segments linear (2-4×0.5-1 mm), subequal rays, oblong fruits with slightly thickened ribs, obconic stylopodium and slightly concave seed face. A molecular analysis based on nuclear ribosomal DNA internal transcribed spacer (ITS) sequences indicated that C.puana is genetically distinct from the other two species of the genus. A distribution map, as well as an updated key, are provided for the species of Cyclorhiza.

7.
Hepatol Int ; 15(5): 1031-1048, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34427860

RESUMEN

BACKGROUND & AIM: Hepatitis B reactivation related to the use of immunosuppressive therapy remains a major cause of liver-related morbidity and mortality in hepatitis B endemic Asia-Pacific region. This clinical practice guidelines aim to assist clinicians in all disciplines involved in the use of immunosuppressive therapy to effectively prevent and manage hepatitis B reactivation. METHODS: All publications related to hepatitis B reactivation with the use of immunosuppressive therapy since 1975 were reviewed. Advice from key opinion leaders in member countries/administrative regions of Asian-Pacific Association for the study of the liver was collected and synchronized. Immunosuppressive therapy was risk-stratified according to its reported rate of hepatitis B reactivation. RECOMMENDATIONS: We recommend the necessity to screen all patients for hepatitis B prior to the initiation of immunosuppressive therapy and to administer pre-emptive nucleos(t)ide analogues to those patients with a substantial risk of hepatitis and acute-on-chronic liver failure due to hepatitis B reactivation.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Antivirales , Hepatitis B/tratamiento farmacológico , Hepatitis B/prevención & control , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica/tratamiento farmacológico , Humanos , Inmunosupresores/efectos adversos , Activación Viral
8.
Zhongguo Zhong Yao Za Zhi ; 44(2): 261-264, 2019 Jan.
Artículo en Chino | MEDLINE | ID: mdl-30989942

RESUMEN

Metabarcoding technology is a research method derived from the combination of traditional DNA barcodes and highthroughput sequencing technologies. It can quickly,easily and efficiently identify and restore biological samples from multiple species.Biological species are currently widely used in environmental biology research. In the market of traditional Chinese medicines,adulteration and quality instability have severely restricted the sustainable development of the related industries. This article introduced the background of the metabarcoding technology and its preliminary application in the identification of Chinese patent medicines. It also outlined the possible problems in the research process and prospected to the development of the DNA metabarcoding technology.


Asunto(s)
Código de Barras del ADN Taxonómico , Medicamentos Herbarios Chinos/normas , Medicina Tradicional China , Medicamentos sin Prescripción/normas , ADN
9.
Front Plant Sci ; 10: 429, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31024595

RESUMEN

Ligustici Rhizoma et Radix (LReR), an important Chinese medicine known as "Gao-ben," refers to Ligusticum sinense Oliv. or Ligusticum jeholense Nakai et Kitag. However, a number of other species are commonly sold as "Gao-ben" in the herbal medicine market, which may result in a series of quality control problems and inconsistent therapeutic effects. The "Gao-ben" is commonly sold sliced and dried, making traditional identification methods difficult. Here, the mini barcode ITS2 region was examined on 68 samples representing LReR and 7 potential adulterant or substitute species. The results showed 100% success rates of PCR and sequencing and the existence of a barcoding gap. The neighbor-joining (NJ) tree indicated that all the tested samples could be exactly identified. The ITS2 secondary structure revealed a clear difference between true "Gao-ben" and three adulterant species. We therefore recommend the use of ITS2 as a mini barcode for distinguishing between closely or distantly related plant species that may be used in Chinese medicine.

10.
Immunol Lett ; 213: 55-61, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30849400

RESUMEN

Circulating T follicular helper (cTFH) cells have been demonstrated to be involved in B-cell-mediated alloreactive responses in kidney and liver transplantation; however, whether these cells are involved in acute liver allograft rejection after liver transplantation, and which subsets are involved, remains to be clarified. The present study aimed to investigate the profiles of cTFH cells in acute liver allograft rejection, including the CXC motif receptor 3 (CXCR3)+ chemokine receptor 6 (CCR6)- subset, the CXCR3-CCR6- subset, and the CXCR3-CCR6+ subset. Twelve liver transplant patients with acute rejection (AR) and 20 with no acute rejection (NAR) were enrolled in the study. The results showed that the proportion of CXCR3-CCR6-CXCR5+CD4+ T cells was significantly increased and the proportion of CXCR3-CCR6+CXCR5+CD4+ T cells was significantly decreased in patients with AR compared with patients with NAR. In addition, the proportion of CXCR3-CCR6-CXCR5+CD4+ T cells was positively correlated with the proportion of B cells in patients with AR. The level of serum interleukin (IL)-21 was higher in the AR group than in the NAR groups. Furthermore, the proportion of CXCR3-CCR6-CXCR5+CD4+ T cells was positively correlated with alanine amino transferase (ALT), whereas the proportion of CXCR3-CCR6+ CXCR5+CD4+ T cells was negatively correlated with ALT. B cells and TFH cells were detected in follicular-like structures in liver allograft tissues from patients with AR. These results suggest that CXCR3-CCR6-CXCR5+CD4+ T cells may be involved in acute allograft rejection after liver transplantation.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Quimiocina CX3CL1/inmunología , Rechazo de Injerto/inmunología , Trasplante de Hígado , Receptores CCR6/inmunología , Receptores CXCR5/inmunología , Enfermedad Aguda , Adulto , Anciano , Aloinjertos , Linfocitos T CD4-Positivos/patología , Femenino , Estudios de Seguimiento , Rechazo de Injerto/patología , Humanos , Masculino , Persona de Mediana Edad
11.
Ann Bot ; 123(6): 1089-1098, 2019 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-30852591

RESUMEN

BACKGROUND AND AIMS: Tertiary relict and Arctic/circumboreal distributions are two major patterns of Northern Hemisphere intercontinental disjunctions with very different histories. Each has been well researched, but members of one biome have generally not been incorporated in the biogeographical analyses of the other, and links or transitions between these two biomes have rarely been addressed. METHODS: Phylogenies of Chimaphila were generated based on cpDNA and nuclear ITS, using Bayesian and maximum likelihood methods. A time-calibrated phylogeny was generated using BEAST. Ancestral area reconstruction was inferred using both statistical dispersal-vicariance analysis and a dispersal-extinction-cladogenesis model. KEY RESULTS: The Chimaphila crown group was estimated to have originated in the early Miocene. The lineages of C. umbellata diverged early, but its present circumboreal distribution was not achieved until around the middle Pliocene or later. Sister to this is a clade of four species with Tertiary relict distribution. Among these, two expansions occurred from North America to Asia, probably via the Bering Land Bridge, generating its current disjunctions. CONCLUSIONS: Our data concur with a few other studies, indicating that the circumboreal woodland biome has an older origin than most true Arctic-alpine taxa, having gradually recruited taxa since the early Oligocene. For the origin of Asia-North America disjunctions in Chimaphila, an 'out-of-America' migration was supported. It is not clear in which direction Pyroloideae lineages moved between Tertiary relict disjunctions and Arctic/circumboreal distributions; each biome might have recruited species from the other.


Asunto(s)
Ericaceae , Asia , Teorema de Bayes , Bosques , América del Norte , Filogenia , Filogeografía
12.
Zhongguo Zhong Yao Za Zhi ; 44(24): 5329-5335, 2019 Dec.
Artículo en Chino | MEDLINE | ID: mdl-32237376

RESUMEN

The family Apiaceae( Umbelliferae) includes some of the world's most important medicinal plants,with more than 100 species recorded in the traditional Chinese medicine,of which more than ten species are commonly used medicinal materials. However,due to morphological similarities,high market demands and regional factors,substitutes and adulterants are often mixed with genuine in the medicinal market. Therefore,a comprehensive sorting for these poorly known plants has been done in this study by combining market survey with literature review,including its species,distribution,price and substitutes. According to the statistics,there are 65 genera and 262 species of medicinal plants of Apiaceae in China,with medicinal part mostly from radix and rhizoma. Sichuan province is the most abundant in distribution and planting resources,with about 137 species,followed by Yunnan,Hubei and Gansu provinces.Furthermore,we summarized the genuine and substitutes of 11 medicinal plants,e. g. Bupleurum,Angelica and Peucedanum etc.,which found that the medicinal plants of Apiaceae were substituted or mixed in different taxonomic ranks. This study would contribute to reduce the risk of medicine misuse,as well as explore other plants of Apiaceae with potential medicinal value,to achieve sustainable development of related industries.


Asunto(s)
Apiaceae/clasificación , Medicina Tradicional China , Plantas Medicinales/clasificación , China
13.
Transpl Immunol ; 47: 32-36, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29360498

RESUMEN

Circulating CD4+CXCR5+ T follicular helper cells (cTfh) have been demonstrated to be involved in B cell-mediated systemic autoimmune diseases and alloreactive responses following kidney transplantation; however, whether cTfh cells are involved in alloreactive responses after liver transplantation (LT) remains unclear. Our present study aimed to investigate the characteristics of cTfh, as well as CXCR3+CCR6-Tfh1, CXCR3-CCR6-Tfh2, and CXCR3-CCR6+Tfh17 subsets in liver allograft recipients. A total of 30 liver transplant recipients were enrolled in this study. The frequencies of cTfh, Tfh1, Tfh2, and Tfh17 subsets, and interleukin (IL)-21-producing Tfh cells in the circulating blood were analyzed by flow cytometry. The capacity of cTfh cells to help B cells differentiate into plasmablasts was determined one day before and one month after LT. The results revealed that the frequency of cTfh cells remained unaltered before and after LT. However, the frequency of the cTfh subsets (e.g., Tfh1 and Tfh2 cells) and B cells were reduced one month after LT. Functionally, the capacity of Tfh cells to produce IL-21 was reduced one month after LT. In addition, cTfh cells exhibited the capacity to help B cells differentiate into plasmablasts in an IL-21-dependent manner in vitro, which was reduced after LT, despite the unaltered production of IgM and IgG by plasmablasts. Thus, our data suggest that cTfh cells may be involved in alloreactive responses following LT via helping B cells differentiate into plasmablasts and plasma cells.


Asunto(s)
Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Trasplante de Hígado , Células Plasmáticas/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Circulación Sanguínea , Comunicación Celular , Diferenciación Celular , Células Cultivadas , Centro Germinal/citología , Humanos , Inmunofenotipificación , Interleucinas/metabolismo , Activación de Linfocitos , Proyectos Piloto , Receptores CXCR3/metabolismo , Receptores CXCR5/metabolismo
14.
Plant Divers ; 38(3): 142-148, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30159458

RESUMEN

Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture, logging, planting of economic plants, mining activities and changing environment. The aims of the study are to investigate climate change-induced changes of subtropical evergreen broad-leaved forests in Yunnan and identify areas of current species richness centers for conservation preparation. Stacked species distribution models were created to generate ensemble forecasting of species distributions, alpha diversity and beta diversity for Yunnan's subtropical evergreen broad-leaved forests in both current and future climate scenarios. Under stacked species distribution models in rapid climate changes scenarios, changes of water-energy dynamics may possibly reduce beta diversity and increase alpha diversity. This point provides insight for future conservation of evergreen broad-leaved forest in Yunnan, highlighting the need to fully consider the problem of vegetation homogenization caused by transformation of water-energy dynamics.

15.
Int J Clin Exp Med ; 8(7): 11636-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26379998

RESUMEN

In this study, we reported a case of de novo autoimmune hepatitis. In this case, liver puncture biopsy was carried out and the result showed autoimmune hepatitis. In this report, we described the characteristics of this patient.

16.
Exp Clin Transplant ; 13(4): 371-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25924105

RESUMEN

Hyperlipidemia is not unusual in liver transplant recipients, but refractory severe hyperlipidemia is unusual. We treated a 39-year-old man who had severe dyslipidemia after liver transplant. The levels of blood lipids, liver enzymes, and essential indicators of liver pathology were monitored. The first serum sample was collected from the liver recipient 56 days after transplant surgery because samples could not be obtained sooner after the transplant. The levels of liver enzymes and blood lipids were improved with symptomatic treatment but had recurrent fluctuations. Tacrolimus and cyclosporine, even at low doses, may have been the dominant factor affecting the blood lipid levels in the recipient.


Asunto(s)
Ciclosporina/efectos adversos , Hiperlipidemias/inducido químicamente , Inmunosupresores/efectos adversos , Lípidos/sangre , Trasplante de Hígado/efectos adversos , Tacrolimus/efectos adversos , Adulto , Biomarcadores/sangre , Biopsia , Sustitución de Medicamentos , Quimioterapia Combinada , Rechazo de Injerto/etiología , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/diagnóstico , Hiperlipidemias/terapia , Masculino , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
17.
Zhonghua Gan Zang Bing Za Zhi ; 23(11): 860-4, 2015 Nov.
Artículo en Chino | MEDLINE | ID: mdl-26743248

RESUMEN

OBJECTIVE: To describe the outcomes and recurrence of autoimmune hepatitis (AIH) after liver transplantation. METHODS: Clinical data of 16 patients with AIH who underwent liver transplantation were analyzed retrospectively. The postoperative cumulative survival rate of the patients was calculated. The postoperative rejections and AIH recurrence were analyzed. The Kaplan-Meier method was used for statistical analysis of survival. RESULTS: All patients were female, with an average age of 52.6 years (range: 41-66 years), and an average MELD score of 21.4. According serological analysis, 15 patients were AIH type 1 and 1 patient was AIH type 2. Three patients died, including 2 of pulmonary infection and 1 of graft dysfunction.The 1-, 2-and 5-year cumulative survival rates were 93.8%, 87.1% and 79.1%, respectively. Five cases (31.3%) of recurrent AIH were diagnosed based on histological evidence. Acute rejection occurred in 6 (37.5%) patients, and de novo HBV infection occurred in 1 (6.3%) patient. CONCLUSION: Liver transplantation is an effective treatment for end-stage AIH. Recurrence and rejection were commonly associated with AIH, but did not negatively impact patient survival.


Asunto(s)
Hepatitis Autoinmune/cirugía , Trasplante de Hígado , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Periodo Posoperatorio , Recurrencia , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
18.
PLoS One ; 9(11): e112135, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25372875

RESUMEN

CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) and Th17 cells are known to be involved in the alloreactive responses in organ transplantation, but little is known about the relationship between Tregs and Th17 cells in the context of liver alloresponse. Here, we investigated whether the circulating Tregs/Th17 ratio is associated with acute allograft rejection in liver transplantation. In present study, thirty-eight patients who received liver transplant were enrolled. The patients were divided into two groups: acute allograft rejection group (Gr-AR) (n = 16) and stable allograft liver function group (Gr-SF) (n = 22). The frequencies of circulating Tregs and circulating Th17 cells, as well as Tregs/Th17 ratio were determined using flow cytometry. The association between Tregs/Th17 ratio and acute allograft rejection was then analyzed. Our results showed that the frequency of circulating Tregs was significantly decreased, whereas the frequency of circulating Th17 cells was significantly increased in liver allograft recipients who developed acute rejection. Tregs/Th17 ratio had a negative correlation with liver damage indices and the score of rejection activity index (RAI) after liver transplantation. In addition, the percentages of CTLA-4(+), HLA-DR(+), Ki67(+), and IL-10(+) Tregs were higher in Gr-SF group than in Gr-AR group. Our results suggested that the ratio of circulating Tregs/Th17 cells is associated with acute allograft rejection, thus the ratio may serve as an alternative marker for the diagnosis of acute rejection.


Asunto(s)
Rechazo de Injerto , Trasplante de Hígado , Linfocitos T Reguladores , Células Th17 , Enfermedad Aguda , Adulto , Aloinjertos , Antígenos de Diferenciación/sangre , Antígenos de Diferenciación/inmunología , Recuento de Linfocito CD4 , Femenino , Rechazo de Injerto/sangre , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/patología , Células Th17/inmunología , Células Th17/metabolismo , Células Th17/patología
19.
Ann Bot ; 114(8): 1701-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25326138

RESUMEN

BACKGROUND AND AIMS: In the Northern Hemisphere, Tertiary relict disjunctions involve older groups of warm affinity and wide disjunctions, whereas circumboreal distributions in Arctic-Alpine taxa tend to be younger. Arctic-Alpine species are occasionally derived from Tertiary relict groups, but Pyrola species, in particular, are exceptional and they might have occurred multiple times. The aim of this study was to reconstruct the biogeographic history of Pyrola based on a clear phylogenetic analysis and to explore how the genus attained its circumboreal distribution. METHODS: Estimates of divergence times and ancestral geographical distributions based on neutrally evolving DNA sequence variation were used to develop a spatio-temporal model of colonization patterns for Pyrola. KEY RESULTS: Pyrola originated and most diversification occurred in Asia; North America was reached first by series Scotophyllae in the late Miocene, then by sub-clades of series Pyrola and Ellipticae around the Pliocene. The three circumboreal taxa, P. minor, P. chlorantha and the P. rotundifolia complex, originated independently of one another, with the last two originating in Asia. CONCLUSIONS: Three circumboreal Pyrola lineages have arisen independently and at least two of these appear to have originated in Asia. The cool, high-altitude habitats of many Pyrola species and the fact that diversification in the genus coincided with global cooling from the late Miocene onwards fits a hypothesis of pre-adaptation to become circumboreal within this group.


Asunto(s)
Evolución Biológica , Pyrola/fisiología , Secuencia de Bases , Calibración , Filogenia , Filogeografía , Factores de Tiempo
20.
Biomed Res Int ; 2014: 836025, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25243186

RESUMEN

Caveolin-1 and flotillin-1 are considered as markers of lipid rafts which can be regarded as sorting platforms for targeted transport of transmembrane proteins and are involved in fundamental cellular events such as signal transduction, cell adhesion, lipid/protein sorting, and human cancer. We addressed caveolin-1 and flotillin-1 expression in 90 human hepatocellular carcinoma (HCC) and adjacent noncancerous tissues (ANT) samples by SDS-PAGE and immunoblotting with specific antibodies. Significant caveolin-1 and flotillin-1 overexpression was found in HCC tissues compared to ANT and was confirmed by immunohistochemistry. Raft-associated Akt signaling pathway components involved in the regulation of cell survival were altered by western blotting in HCC microdomain-enriched subcellular fractions purified from paired HCC and ANT samples. Our results demonstrated that the activity of raft-associated but not total membrane Akt determines its cellular functions. Lipid rafts differ in different types of tissues, which allows for the possibility of tissue-type-specific targeting for cell survival.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Microdominios de Membrana/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/fisiología , Adulto , Anciano , Carcinoma Hepatocelular/patología , Caveolina 1/análisis , Caveolina 1/metabolismo , Supervivencia Celular/fisiología , Femenino , Humanos , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad
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