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1.
Medicine (Baltimore) ; 99(23): e20050, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32501967

RESUMO

INTRODUCTION: Enteropathy-associated T-cell lymphoma (EATL) is a very rare form of lymphoma in the gastrointestinal tract. The proximal jejunum and ileum are the most common sites of EATL, whereas EATL rarely arises in the duodenum, and EATL involving metastasis of the bilateral ovaries is even rarer. PATIENT CONCERNS: A 43-year-old female suffered from upper abdominal pain and weight loss for 3 months. DIAGNOSIS: Type II EATL. INTERVENTIONS: The patient was initially treated with chemotherapies, including 4 cycles of the CHOP-E and 2 cycles of the DHAP+ chidamide chemotherapy regimens. However, the patient did not respond well to chemotherapy. Surgical treatment of the duodenal obstruction, with perforation of small intestine and the duodenum, was performed successively. OUTCOMES: The patient died of septic shock only 1 day after the surgery for the second perforation. Her overall survival was 11 months from the time of initial diagnosis. CONCLUSION: This case suggests that EALT is highly invasive and its clinical course is very aggressive. Intestinal perforation, intestinal obstruction, or involvement of extraintestinal organs may occur in EALT patients. Additionally, EALT patients respond poorly to chemotherapy and have an extremely unfavorable prognosis.


Assuntos
Duodenopatias/patologia , Linfoma de Células T Associado a Enteropatia/patologia , Adulto , Feminino , Humanos , Obstrução Intestinal/complicações , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Neoplasias Ovarianas/secundário
2.
Medicine (Baltimore) ; 99(10): e19440, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32150096

RESUMO

RATIONALE: Although the early detection and treatment of non-metastatic esophageal cancer has improved, these patients' prognoses are still poor. Most patients with radical treatment for esophageal cancer will relapse in 3 years, and the best treatment strategy after recurrence has not been uniformly accepted. Multiform treatments may be beneficial to recurrent patients. PATIENT CONCERNS: A 60-year-old male patient, due to routinely health examination, ulcerated lesions 30 cm away from the incisors were found by gastroscopy, pathology showed esophageal squamous cell carcinoma (ESCC). DIAGNOSIS: Due to the patient's pathology, he was diagnosed with ESCC. INTERVENTIONS: The patient underwent radical surgery for ESCC on June 28, 2015. The left cervical lymph node metastasis occurred after 20 months, and lymph node metastasis carcinoma resection was performed. After that, concurrent chemoradiotherapy was implemented, 40 days after the end of the 4 courses of chemotherapy, the left cervical metastatic lymph nodes relapsed, radioactive particle implantation was carried out, and progressed again after 1 month. The patient took apatinib for 1 week but could not tolerate due to hand-foot syndrome. Immune checkpoint inhibitor (ICI) was administered since October 27, 2017. OUTCOMES: The therapeutic effect of immune checkpoint inhibitor was evaluated as partial response (PR) after 6 courses of treatment and complete response (CR) after 15 courses of treatment. To our knowledge, this is the first case report of successful immunotherapy for refractory esophageal squamous cell carcinoma. LESSONS: The emergence of ICIs promotes the treatment of esophageal cancer to a new era. Our observations suggest that patients for whom schedule to receive anti-programmed cell death protein-1 (anti-PD-1)/programmed cell death-ligand 1 (PD-L1) immunotherapy may require genomic testing to predict whether tumors respond to ICIs. In this case, we also present the predictors for the efficacy of targeted immunotherapy. At present, no matter which predictor of PD-L1 expression, tumor mutational burden (TMB), microsatellite instability (MSI), and tumor-infiltrating lymphocyte (TIL), a single predictor may be unconvincing and cannot accurately estimate the efficacy of immunotherapy. Multiplex detecting methods and combined biomarkers may provide new strategies. Consensus need to be reached in order to be widely applied in future studies.


Assuntos
Vértebras Cervicais , Neoplasias Esofágicas/diagnóstico , Carcinoma de Células Escamosas do Esôfago/diagnóstico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Quimiorradioterapia , Diagnóstico Diferencial , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/secundário , Carcinoma de Células Escamosas do Esôfago/terapia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade
3.
Langmuir ; 36(3): 789-795, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31815486

RESUMO

We report a facile yet general in situ seed-mediated method for the synthesis of polymer-grafted gold nanoparticles with narrow size distributions (<10%), accurately tunable sizes, and excellent colloidal stability. This method can be extended to a broad range of types and molecular weights of polymer ligands. Nanoparticles with different shapes can also be prepared by using preformed shaped nanoparticles directly as the seeds.

4.
Hum Cell ; 33(1): 104-115, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758392

RESUMO

MiR-663b has been demonstrated to be abnormally expressed in several cancer types and was involved in the progression of cancer. Although overexpression of miR-663b in colorectal cancer was observed, the role of miR-663b in colorectal cancer cells has not been identified yet. In this study, we analyzed expression of miR-663b in colorectal tumors and explored the molecular mechanism of miR-663b in colorectal cancer cells. MiR-663b was significantly overexpressed in colorectal tumors and cell lines. Downregulation of miR-663b inhibited cell proliferation and sphere forming ability in colorectal cancer cells. In addition, miR-663b downregulation inactivated Ras/Raf signaling activity and subsequently decreased YAP1 and CD44 expression in colorectal cancer cells. Using TargetScan software, TNK1, a negative regulator of Ras/Raf signaling, was predicted to be a target gene of miR-663b. Western blotting and RT-qPCR showed that TNK1 expression was negatively regulated by miR-663b. In addition, the direct binding of miR-663b to TNK1 mRNA was proved by dual luciferase reporter assay. Furthermore, downregulation of miR-663b inhibited colorectal cancer cell proliferation and stemness, which was reversed after siRNA-mediated silencing of TNK1. In conclusion, the current study revealed a pivotal role of miR-663b in the progression of colorectal cancer.

5.
Cancers (Basel) ; 11(10)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615107

RESUMO

One of many types of extracellular vesicles (EVs), exosomes are nanovesicle structures that are released by almost all living cells that can perform a wide range of critical biological functions. Exosomes play important roles in both normal and pathological conditions by regulating cell-cell communication in cancer, angiogenesis, cellular differentiation, osteogenesis, and inflammation. Exosomes are stable in vivo and they can regulate biological processes by transferring lipids, proteins, nucleic acids, and even entire signaling pathways through the circulation to cells at distal sites. Recent advances in the identification, production, and purification of exosomes have created opportunities to exploit these structures as novel drug delivery systems, modulators of cell signaling, mediators of antigen presentation, as well as biological targeting agents and diagnostic tools in cancer therapy. This review will examine the functions of immunocyte-derived exosomes and their roles in the immune response under physiological and pathological conditions. The use of immunocyte exosomes in immunotherapy and vaccine development is discussed.

6.
Biosci Rep ; 39(8)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31350343

RESUMO

To investigate the role of microRNA-497-5p (miR-497-5p) in the tumorigenesis of colorectal cancer (CRC), the present study applied qRT-PCR to detect the expression level of miR-497-5p in both clinical samples and CRC cell lines. Furthermore, to specifically evaluate the carcinogenic role of miR-497-5p in CRC, the expression of miR-497-5p was monitored by transfecting with the mimics or inhibitors of miR-497-5p. Transwell assay as well as CCK-8 assay were used to determine the functions of miR-497-5p on cell invasion, migration and proliferation, respectively. miR-497-5p expression was remarkably down-regulated in clinical samples with cancer development as well as in CRC cell lines. Additionally, low miR-497-5p expression was remarkably correlated with higher TNM stage and lymph node metastasis of CRC patients. Up-regulation of miR-497-5p significantly inhibited proliferation, migration, and invasion of LOVO CRC cell line. Conversely, antagonizing miR-497-5p significantly promoted cell proliferation, migration and invasion. Mechanistic analysis revealed that miR-497-5p directly bound to its downstream target, protein tyrosine phosphatase non-receptor type 3 (PTPN3), whose aberrant expression partially reversed inhibition of cell proliferation and migration. Taken together, the present study elucidated the inhibitory role of miR-497-5p in CRC via targeting PTPN3, which potentiated miR-497-5p as a potential therapeutic target for combating CRC.

7.
Mol Diagn Ther ; 23(5): 579-601, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325035

RESUMO

Bladder cancer (BC) is the second highest morbid malignancy of the urinary tract and the fifth most common cancer worldwide. BC is highly malignant with significant morbidity and mortality, especially muscle-invasive BC (MIBC), which has a poor prognosis and frequently recurs after the first resection. Therefore, more sensitive diagnostic tools and effective therapeutic methods are urgently needed. MicroRNAs (miRNAs) are small noncoding RNAs that regulate the expression of protein-coding genes by repressing their translation or cleaving RNA transcripts in a sequence-specific manner. miRNAs play very important roles in regulating genes related to tumorigenesis, tumor development, progression, metastasis and angiogenesis. With the rapid development of high-throughput sequencing technology, an increasing number of miRNAs with aberrant expression between either BC patients and healthy volunteers or between BC tumor tissues and matched peripheral control tissues have been recently examined. The tumor etiopathogenesis must be determined to promote the development of new markers as diagnostic and prognostic tools and targets for bladder tumor therapy, it is therefore vital to elucidate the function of miRNAs with aberrant expression in BC. In the present study, we examined the published data of BC-related miRNAs by reviewing their expression levels, possible functions, potential target genes, related molecular regulatory networks, candidate markers for prognosis and diagnosis, and prospective therapeutic cases, and we summarized the status of research on BC-related miRNAs in recent years.


Assuntos
Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Bexiga Urinária/genética , Exossomos , Humanos , Técnicas de Diagnóstico Molecular , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Interferência de RNA , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/terapia
8.
Oncol Lett ; 17(3): 3406-3410, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30867777

RESUMO

Expression of miR-124 in gastric adenocarcinoma cell line SGC-7901 and its effect on biological functions was investigated. Expression of miR-124 in cancer tissues and paracancerous tissues of gastric adenocarcinoma patients was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). RT-qPCR was used to detect the expression of miR-124 in human normal gastric epithelial cells GES-1 and gastric adenocarcinoma SGC-7901 cells. Cells in miR-124 group were transfected with miR-124 agomir, cells in NC group were transfected with agomir-negative control sequence and cells in the control group were not transfected. MTT assay was used to detect cell proliferation, and Transwell invasion assay to detect cell invasion ability, and the effect of transfected miR-124 agonist on the proliferation and invasive ability of gastric adenocarcinoma cells was evaluated. RT-qPCR results showed that miR-124 expression was significantly downregulated in gastric adenocarcinoma tumor tissues compared with paracancerous tissues. Compared with cells of normal human gastric epithelial cell line GES-1, the expression of miR-124 human gastric adenocarcinoma SGC-7901 cells was significantly downregulated. At 12 h, there was no significant difference in OD at 490 nm in the three groups (P>0.05). OD (490) in the three groups showed a gradual upward trend. After transfection, proliferation curves of the three groups showed an upward trend, proliferation rate of miR-124 group was significantly lower than that of NC and control groups (P<0.05). The number of invading cells in miR-124 group was significantly lower than that in NC group and control group, but there was no significant difference in the number of cell invasion between the NC and control groups. miR-124 can inhibit the proliferation and invasion of gastric adenocarcinoma cells. Downregulation of miR-124 expression in gastric adenocarcinoma may be closely related to the development of gastric adenocarcinoma.

9.
Mol Ther Nucleic Acids ; 19: 612-618, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31945724

RESUMO

Long non-coding RNAs (lncRNAs) are associated with a spectrum of biological processes such as gene regulation on transcriptional and post-transcriptional levels. The HOXA transcript at the distal tip (HOTTIP) lncRNA plays an important role in carcinogenesis; however, the underlying role of HOTTIP in colorectal carcinoma (CRC) remains unknown. The aim of the present study was to evaluate the expression and function of HOTTIP in CRC. In the present study, we analyzed HOTTIP expression levels of CRC patients in tumor and adjacent normal tissue by real-time quantitative PCR. Knockdown of HOTTIP by RNA interference was performed to explore its roles in cell proliferation, migration, and invasion. Our results found that HOTTIP was upregulated in human primary CRC tissues. Knockdown of HOTTIP inhibited CRC cell proliferation, migration, and invasion. Above all, knockdown of HOTTIP could represent a rational therapeutic strategy for CRC.

10.
Neuropharmacology ; 141: 126-138, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30170081

RESUMO

We have previously reported that the miR-181a/Prox1/Notch1 pathway mediates the effect of morphine on modulating lineage-specific differentiation of adult neural stem/progenitor cells (NSPCs) via a PKCε-dependent pathway, whereas fentanyl shows no such effect. However, the role of the PKCε/Prox1 pathway in mediating drug-associated contextual memory remains unknown. The current study investigated the effect of PKCε/Prox1 on morphine-induced inhibition of adult neurogenesis and drug-associated contextual memory in mice, while the effect of fentanyl was tested simultaneously. By using BrdU labeling, we were able to examine the lineages of differentiated NSPCs in adult DG. PKCε knockout blocked morphine's effects on inducing in vivo astrocyte-preferential differentiation of NSPCs, but did not alter NSPC lineages upon fentanyl treatment. Inhibited adult neurogenesis further resulted in prolonged extinction and enhanced reinstatement of morphine-induced CPP, as well as prolonged extinction of space reference memory indicated by the Morris water maze paradigm. However, after fentanyl administration, no significant changes were found between wild-type and PKCε knockout mice, during either CPP or water maze tasks. When the lentivirus encoding Nestin-promoter-controlled Prox1 cDNA was injected into hippocampi of wildtype and PKCε knockout adult mice to modulate PKCε/Prox1 activity, similar effects were discovered in adult mice injected with lentivirus encoding Prox1, and more dramatic effects were found in PKCε knockout mice with concurrent Prox1 overexpression. In conclusion, morphine mediates lineage-specific NSPC differentiation, inhibits adult neurogenesis and regulates contextual memory retention via the PKCε/Prox1 pathway, which are implicated in the eventual context-associated relapse.


Assuntos
Extinção Psicológica/efeitos dos fármacos , Proteínas de Homeodomínio/metabolismo , Memória/efeitos dos fármacos , Morfina/farmacologia , Neurogênese/efeitos dos fármacos , Proteína Quinase C-épsilon/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Condicionamento Psicológico/efeitos dos fármacos , Giro Denteado/metabolismo , Fentanila/farmacologia , Vetores Genéticos/administração & dosagem , Proteínas de Homeodomínio/genética , Lentivirus/genética , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Knockout , Microinjeções , Morfina/antagonistas & inibidores , Células-Tronco Neurais/citologia , Proteína Quinase C-épsilon/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética
11.
Int J Med Sci ; 15(10): 1014-1024, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013443

RESUMO

Autophagy is a catabolic process to maintain intracellular homeostasis via removal of cytoplasmic macromolecules and damaged cellular organelles through lysosome-mediated degradation. Trehalose is often regarded as an autophagy inducer, but we reported previously that it could prevent ischemic insults-induced autophagic death in neurons. Thus, we further investigated in this study whether trehalose could protect human dopaminergic SH-SY5Y cells against H2O2-induced lethal autophagy. We found pretreatment with trehalose not only prevented H2O2-induced death in SH-SY5Y cells, but also reversed H2O2-induced upregulation of LC3II, Beclin1 and ATG5 and downregulation of p62. Then, we proved that either autophagy inhibitor 3MA or genetic knockdown of ATG5 prevented H2O2-triggered death in SH-SY5Y cells. These indicated that trehalose could inhibit H2O2-induced autophagic death in SH-SY5Y cells. Further, we found that trehalose inhibited H2O2-induced AMPK activation and endoplasmic reticulum (ER) stress. Moreover, inhibition of AMPK activation with compound C or alleviation of ER stress with chemical chaperone 4-PBA obviously attenuated H2O2-induced changes in autophagy-related proteins. Notably, we found that trehalose inhibited H2O2-induced increase of intracellular ROS and reduction in the activities of CAT and SOD. Consistently, our data revealed as well that mitigation of intracellular ROS levels with antioxidant NAC markedly attenuated H2O2-induced AMPK activation and ER stress. Therefore, we demonstrated in this study that trehalose prevented H2O2-induced autophagic death in SH-SY5Y cells via mitigation of ROS-dependent endoplasmic reticulum stress and AMPK activation.


Assuntos
Apoptose , Autofagia , Estresse do Retículo Endoplasmático , Trealose/fisiologia , Animais , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/toxicidade , Neuroblastoma/patologia , Espécies Reativas de Oxigênio
12.
Medicine (Baltimore) ; 96(40): e8205, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28984772

RESUMO

To report and compare 2 modified approaches for the active removal of silicone oil (ROSO) with a 23-gauge transconjunctival vitrectomy system.This prospective single blinded study was conducted from January 2015 to December 2016. Eighty-nine eyes of 86 patients who underwent silicone oil removal were enrolled. Patients were randomly divided into either group A or B. In group A, the fluid-air exchange tube was connected to a 1 mL syringe with the plunger removed and the tip was dilated with a hemostat so that it fit into the cap of the 23-gauge cannula to form a seal for oil drainage. In group B, the tip of the syringe was closely attached to the cap of the 23-gauge cannula by a tube adaptor, which was salvaged from a used silicone oil inject and aspirate pack and sterilized. Main outcome measures were time required for silicone oil removal, silicone oil residual, intraoperative and postoperative complications including hypotony, bleeding, and retinal redetachment.The mean time required was 6.08 ±â€Š0.31 minutes and 6.11 ±â€Š0.31 minutes for groups A and B, respectively. No silicone oil residual, severe hypotony, recurrence of retinal detachment, or impairment of visual acuity were observed in either group. Conjunctival injection and hyperemia were slightly more severe in group A, but spontaneously resolved in 2 to 3 days.Both methods described in this paper were demonstrated to be safe, effective, and cost-effective for the ROSO. The syringe dilation method caused more severe conjuntival irritation, thus we suggest using the tube adaptor method for hospitals equipped with cold sterilization equipment.


Assuntos
Drenagem/instrumentação , Descolamento Retiniano/cirurgia , Óleos de Silicone , Vitrectomia/instrumentação , Cânula , Túnica Conjuntiva/cirurgia , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Método Simples-Cego , Seringas , Resultado do Tratamento , Vitrectomia/métodos
13.
J Pharm Biomed Anal ; 108: 56-60, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25710903

RESUMO

Pseudolaric acid B (PAB), which is the main biologically active diterpene acid of Pseudolarix kaempferi, has presented anti-fungal, anti-tumor, anti-fertility, and anti-tubulin activities. In this study, a sensitive and selective liquid chromatography tandem mass spectrometry (LC-MS/MS) method with multiple-reaction monitoring mode was employed for quantification of PAB in rat plasma. The calibration curve was linear over the range of 0.86-288 ng/mL with correlation coefficient (r) greater than 0.995 for PAB, and the lower limit of quantification was 0.86 ng/mL in rat plasma. The accuracy of PAB was between -9.1% and 7.0% relative error, and precision ranged from 1.2 to 10.6% relative standard deviation. This method was successfully applied to the pharmacokinetic studies of PAB in Sprague-Dawley rats. After single intravenous administration of 2.0, 4.0, and 8.0mg/kg PAB to rats, the t1/2 were (16.1 ± 5.6), (30.0 ± 13.7), and (27.4 ± 5.3)min, respectively. The pharmacokinetics (C(2min), AUC) of PAB within the used dosage range were in accordance with linear pharmacokinetic characteristics.


Assuntos
Cromatografia Líquida/métodos , Diterpenos/farmacocinética , Pinaceae/química , Espectrometria de Massas em Tandem/métodos , Administração Intravenosa , Animais , Área Sob a Curva , Calibragem , Diterpenos/administração & dosagem , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Meia-Vida , Limite de Detecção , Masculino , Casca de Planta , Raízes de Plantas , Ratos , Ratos Sprague-Dawley
14.
Peptides ; 59: 89-93, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25038511

RESUMO

The present study was designed to assess the usefulness of measuring plasma levels of copeptin (a peptide co-released with the hypothalamic stress hormone vasopressin) as a biomarker for the severity of carbon monoxide (CO) poisoning and for predicting delayed neurological sequelae (DNS). Seventy-two patients with CO poisoning and 72 sex and age matched healthy individuals were recruited. Plasma copeptin levels were measured on admission from CO poisoning patients and for healthy individuals at study entry by using a sandwich immunoassay. The CO poisoning patients were divided into two groups according to severity (unconscious and conscious) and occurrence of DNS. The mean plasma copeptin levels (52.5±18.5 pmol/L) in the unconscious group were significantly higher than in the conscious group (26.3±12.7 pmol/L) (P<0.001). Plasma copeptin levels of more than 39.0 pmol/L detected CO poisoning with severe neurological symptoms e.g. unconsciousness (sensitivity 84.6% and specificity 81.4%). The plasma copeptin levels were higher in patients with DNS compared to patients without DNS (52.2±20.6 pmol/L vs. 27.9±14.8 pmol/L, P<0.001). Plasma copeptin levels higher than 40.5 pmol/L predicted the development of DNS (sensitivity 77.8%, specificity 82.1%). Plasma copeptin levels were identified as an independent predictor for intoxication severity [odds ratio (OR) 1.261, 95% confidence interval (CI) 1.112-1.638, P=0.002] and DNS (OR 1.313, 95% CI 1.106-1.859, P=0.001). Thus, plasma copeptin levels independently related to intoxication severity and were identified as a novel biomarker for predicting DNS after acute CO poisoning.


Assuntos
Intoxicação por Monóxido de Carbono/sangue , Glicopeptídeos/sangue , Doenças do Sistema Nervoso/sangue , Doença Aguda , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Índice de Gravidade de Doença
15.
Sci Rep ; 4: 4208, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24572610

RESUMO

In this study, 111 Cryptosporidium parvum IId isolates from several species of animals in China, Sweden, and Egypt were subtyped by multilocus sequence typing (MLST). One to eleven subtypes were detected at each of the 12 microsatellite, minisatellite, and single nucleotide polymorphism (SNP) loci, forming 25 MLST subtypes. Host-adaptation and significant geographical segregation were both observed in the MLST subtypes. A clonal population structure was seen in C. parvum IId isolates from China and Sweden. Three ancestral lineages and the same RPGR sequence were shared by these isolates examined. Therefore, the present genetic observations including the higher nucleotide diversity of C. parvum IId GP60 sequences in Western Asia, as well as the unique distribution of IId subtypes (almost exclusively found in Asia, Europe, and Egypt) and in combination with the domestication history of cattle, sheep, and goats, indicated that C. parvum IId subtypes were probably dispersed from Western Asia to other geographical regions. More population genetic structure studies involving various C. parvum subtype families using high-resolution tools are needed to better elucidate the origin and dissemination of C. parvum in the world.


Assuntos
Cryptosporidium parvum/classificação , Cryptosporidium parvum/genética , China , Cryptosporidium parvum/isolamento & purificação , Egito , Genes de Protozoários , Variação Genética , Genética Populacional , Desequilíbrio de Ligação , Repetições Minissatélites , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , Suécia
16.
Biomed Chromatogr ; 27(12): 1754-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23843078

RESUMO

A sensitive and rapid LC-MS/MS method was developed and validated for the determination of kadsurenone in rat plasma using lysionotin as the internal standard (IS). The analytes were extracted from rat plasma with acetonitrile and separated on a SB-C18 column (50 × 2.1 mm, i.d.; 1.8 µm) at 30 °C. Elution was achieved with a mobile phase consisting of methanol-water-formic acid (65:35:0.1, v/v/v) at a flow rate of 0.30 mL/min. Detection and quantification for analytes were performed by mass spectrometry in the multiple reaction monitoring mode with positive electrospray ionization m/z at 357.1 → 178.1 for kadsurenone, and m/z 345.1 → 315.1 for IS. Calibration curves were linear over a concentration range of 4.88-1464 ng/mL with a lower limit of quantification of 4.88 ng/mL. The intra- and inter-day accuracies and precisions were <8.9%. The LC-MS/MS assay was successfully applied for oral pharmacokinetic evaluation of kadsurenone using the rat as an animal model.


Assuntos
Benzofuranos/sangue , Cromatografia Líquida/métodos , Lignanas/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Benzofuranos/química , Benzofuranos/farmacocinética , Análise dos Mínimos Quadrados , Lignanas/química , Lignanas/farmacocinética , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
PLoS One ; 7(8): e43782, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22937094

RESUMO

In this study, nine C. muris and 43 C. andersoni isolates from various animals in China were subtyped by a multilocus sequence typing (MLST) tool. DNA sequence analyses showed the presence of 1-2 subtypes of C. muris and 2-6 subtypes of C. andersoni at each of the four loci (MS1, MS2, MS3, and MS16), nine of which represented new subtypes. Altogether, two C. muris and 10 C. andersoni MLST subtypes were detected. Linkage disequilibrium analysis indicated although the overall population structure of the two parasites was clonal, the Chinese C. andersoni in cattle has an epidemic structure. Three and two clusters were produced in the C. muris and C. andersoni populations by Structure 2.3.3 analysis, with Chinese C. muris and C. andersoni substructures differing from other countries. Thus, this study suggested the prevalence of C. andersoni in China is not attributed to the introduction of dairy cattle. More studies involving more genetic loci and systematic sampling are needed to better elucidate the population genetic structure of C. muris and C. andersoni in the world and the genetic basis for the difference in host specificity among the two most common gastric parasites.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/veterinária , Cryptosporidium/genética , DNA de Protozoário/genética , Doenças dos Ovinos/parasitologia , Animais , Sequência de Bases , Bovinos , Cricetinae , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Dados de Sequência Molecular , Análise de Sequência de DNA , Ovinos , Struthioniformes
18.
J Clin Microbiol ; 49(3): 1077-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21177898

RESUMO

To estimate the prevalence and public health significance of cryptosporidiosis in preweaned calves in China, 801 fecal samples from eight farms in seven areas in Henan Province were examined for Cryptosporidium oocysts. The overall infection rate of Cryptosporidium was 21.5%, with the farm in Xinxiang having the highest prevalence (40%). No significant difference in infection rates was observed between seasons. Cryptosporidium spp. were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of the small subunit (SSU) rRNA gene and DNA sequencing of the 60-kDa glycoprotein (gp60) gene. The SSU rRNA-based PCR identified four Cryptosporidium species, including Cryptosporidium parvum (54/172), C. bovis (65/172), C. ryanae (19/172), and C. andersoni (12/172), and the occurrence of infections with mixed species (22/172). The earliest detection of C. bovis was in calves of 1 week of age, showing that the prepatent period was shorter than the previously stated 10 to 12 days. Infections with C. parvum peaked in summer, whereas C. bovis dominated in autumn and winter. There was no apparent difference in the age of cattle infected with either C. parvum or C. bovis. Sequencing analysis of the gp60 gene showed all 67 C. parvum samples belonged to subtype IIdA19G1. These findings suggested that the transmission of Cryptosporidium spp. in preweaned calves in Henan, China, appeared to be different from other areas both at genotype and subtype levels. Further molecular epidemiologic studies (including samples from both calves and humans) are needed to elucidate the transmission dynamics and public significance of C. parvum in cattle in China.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/transmissão , Criptosporidiose/veterinária , Cryptosporidium/classificação , Cryptosporidium/isolamento & purificação , Animais , Bovinos , China , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fezes/parasitologia , Genes de RNAr , Epidemiologia Molecular , Dados de Sequência Molecular , Tipagem Molecular , Polimorfismo de Fragmento de Restrição , Prevalência , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Estações do Ano , Análise de Sequência de DNA
19.
Parasitol Int ; 60(1): 1-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20884374

RESUMO

Dairy industry plays an important role in the agricultural economy of China. To estimate the prevalence and public health significance of cryptosporidiosis in post-weaned and adult dairy cattle in China, during four consecutive years (from 2006 to 2009), a total of 1315 fecal samples from 22 dairy cattle farms in ten prefectures in Henan Province were examined for the presence of Cryptosporidium oocysts. The overall prevalence of Cryptosporidium was 7.9%, with the highest infection rate (11.3%) in 3 to 11-month-old calves and the lowest infection rate (1.0%) in >2-year-old cows (p<0.01). Cryptosporidium-positive samples (n=104) were analyzed by PCR-restriction fragment length polymorphism (RFLP) analysis of the small subunit (SSU) rRNA gene, and 25 representative samples were further analyzed by DNA sequencing of the PCR products. Cryptosporidium bovis and Cryptosporidium andersoni were identified. C. andersoni (84/104) was the predominant species and was found in all age groups, whereas C. bovis (20/104) was only detected in 3 to 11-month-old calves. Thus, C. andersoni appears to be the dominant species in weaned dairy calves and heifers in China, in contrast with its common occurrence in adult cattle in other parts of the world.


Assuntos
Bovinos/parasitologia , Criptosporidiose/epidemiologia , Criptosporidiose/veterinária , Cryptosporidium/isolamento & purificação , Fatores Etários , Animais , China/epidemiologia , Cryptosporidium/genética , DNA de Protozoário/análise , Fezes/parasitologia , Genótipo , Oocistos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Prevalência , Análise de Sequência de DNA , Desmame
20.
Appl Environ Microbiol ; 75(24): 7692-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19820152

RESUMO

To understand the prevalence of Cryptosporidium infection in rodents in China and to assess the potential role of rodents as a source for human cryptosporidiosis, 723 specimens from 18 rodent species were collected from four provinces of China and examined between August 2007 and December 2008 by microscopy after using Sheather's sugar flotation and modified acid-fast staining. Cryptosporidium oocysts were detected in 83 specimens, with an overall prevalence of 11.5%. Phodopus sungorus, Phodopus campbelli, and Rattus tanezumi were new reported hosts of Cryptosporidium. The genotypes and subtypes of Cryptosporidium strains in microscopy-positive specimens were further identified by PCR and sequence analysis of the small subunit rRNA and the 60-kDa glycoprotein (gp60) genes. In addition to Cryptosporidium parvum, C. muris, C. andersoni, C. wrairi, ferret genotype, and mouse genotype I, four new Cryptosporidium genotypes were identified, including the hamster genotype, chipmunk genotype III, and rat genotypes II and III. Mixed Cryptosporidium species/genotypes were found in 10.8% of Cryptosporidium-positive specimens. Sequence analysis of the gp60 gene showed that C. parvum strains in pet Siberian chipmunks and hamsters were all of the subtype IIdA15G1, which was found previously in a human isolate in The Netherlands and lambs in Spain. The gp60 sequences of C. wrairi and the Cryptosporidium ferret genotype and mouse genotype I were also obtained. These findings suggest that pet rodents may be potential reservoirs of zoonotic Cryptosporidium species and subtypes.


Assuntos
Criptosporidiose/veterinária , Cryptosporidium/classificação , Cryptosporidium/isolamento & purificação , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/microbiologia , Animais , Animais Domésticos , Bovinos , China/epidemiologia , Cricetinae , Criptosporidiose/epidemiologia , Criptosporidiose/microbiologia , Cryptosporidium/genética , Humanos , Camundongos , Dados de Sequência Molecular , Filogenia , Ratos , Roedores
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