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1.
Persoonia ; 51: 229-256, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38665984

RESUMEN

Species in Diaporthe have broad host ranges and cosmopolitan geographic distributions, occurring as endophytes, saprobes and plant pathogens. Previous studies have indicated that many Diaporthe species are associated with Citrus. To further determine the diversity of Diaporthe species associated with citrus diseases in China, we conducted extensive surveys in major citrus-producing areas from 2017-2020. Diseased tissues were collected from leaves, fruits, twigs, branches and trunks showing a range of symptoms including melanose, dieback, gummosis, wood decay and canker. Based on phylogenetic comparisons of DNA sequences of the internal transcribed spacer regions (ITS), calmodulin (cal), histone H3 (his3), translation elongation factor 1-alpha (tef1) and beta-tubulin (tub2), 393 isolates from 10 provinces were identified as belonging to 36 species of Diaporthe, including 32 known species, namely D. apiculata, D. biconispora, D. biguttulata, D. caryae, D. citri, D. citriasiana, D. compacta, D. discoidispora, D. endophytica, D. eres, D. fusicola, D. fulvicolor, D. guangxiensis, D. hongkongensis, D. hubeiensis, D. limonicola, D. litchii, D. novem, D. passifloricola, D. penetriteum, D. pescicola, D. pometiae, D. sackstonii, D. sennicola, D. sojae, D. spinosa, D. subclavata, D. tectonae, D. tibetensis, D. unshiuensis, D. velutina and D. xishuangbanica, and four new species, namely D. gammata, D. jishouensis, D. ruiliensis and D. sexualispora. Among the 32 known species, 14 are reported for the first time on Citrus, and two are newly reported from China. Among the 36 species, D. citri was the dominant species as exemplified by its high frequency of isolation and virulence. Pathogenicity tests indicated that most Diaporthe species obtained in this study were weakly aggressive or non-pathogenic to the tested citrus varieties. Only D. citri produced the longest lesion lengths on citrus shoots and induced melanose on citrus leaves. These results further demonstrated that a rich diversity of Diaporthe species occupy Citrus, but only a few species are harmful and D. citri is the main pathogen for Citrus in China. The present study provides a basis from which targeted monitoring, prevention and control measures can be developed. Citation: Xiao XE, Liu YD, Zheng F, et al. 2023. High species diversity in Diaporthe associated with citrus diseases in China. Persoonia 51: 229-256. doi: 10.3767/persoonia.2023.51.06.

2.
Zhonghua Nei Ke Za Zhi ; 61(6): 664-672, 2022 Jun 01.
Artículo en Chino | MEDLINE | ID: mdl-35673747

RESUMEN

Objective: To study the different factors affecting platelet production post transplantation of hematopoietic stem cells (HSCs) isolated from different sources in order to explore novel options for treating platelet depletion following HSCs transplantation. Methods: HSCs and their downstream derivatives including myeloid and lymphoid cells (i.e., collective of mononuclear cells (MNCs)), were isolated from E14.5 fetal liver (FL) and bone marrow (BM) of 8-week-old mice by Ficoll separation technique. These cells were subsequently transplanted into the tibia bone marrow cavity of recipient mice post lethal myeloablative treatment in order to construct the FL-MNCs and BM-MNCs transplantation mouse model. Routine blood indices were examined in these recipient mice. The chimeric rate of donor cells in recipient peripheral blood cells were determined by flow cytometry. Different groups of cells involved in platelet reconstruction were analyzed. CD41+megakaryocytes were sorted from fetal liver or bone marrow using magnetic beads, which were then induced to differentiate into platelets in an in vitro assay. Quantitative RT-PCR was used to detect the expression of platelet-related genes in CD41+megakaryocytes from the two sources. Results: Both the FL-MNCs and the BM-MNCs transplantation groups resumed normal hematopoiesis at the 4th week after transplantation, and the blood cells of the recipient mice were largely replaced by the donor cells. Compared with the mice transplanted with BM-MNCs, the platelet level of mice transplanted with FL-MNCs recovered faster and were maintained at a higher level. At week 4, the PLT level of the FL-MNCs group was (1.45±0.37)×1012/L, and of the BM-MNCs group was (1.22±0.24)×1012/L, P<0.05. The FL-MNCs contain a higher proportion of hematopoietic stem cells (Lin-Sca-1+c-Kit+)(7.60%±1.40%) compared to the BM-MNCs (1.10%±0.46%), P<0.01; the proportion of the megakaryocyte progenitor cells (Lin-Sca-1-c-Kit+CD41+CD150+) and mature megakaryocyte cells (CD41+CD42b+), also differ significantly between the FL-MNCs (3.05%±0.22%, 1.60%±0.06%, respectively) and the BM-MNCs (0.15%±0.02%, 0.87%±0.11%, respectively) groups, both P<0.01. In vitro functional studies showed that FL-MNCs-CD41+megakaryocytes could produce proplatelet-like cells more quickly after induction, with proplatelet-like cells formation on day 3 and significant platelet-like particle formation on day 5, in contrast to bone marrow-derived BM-MNCs-CD41+megakaryocytes that failed to form proplatelet-like cell on day 5. In addition, FL-MNCs-CD41+cells expressed higher levels of platelet-related genes, Mpl (3.25-fold), Fog1 (3-fold), and Gata1 (1.5-fold) (P<0.05). Conclusion: Compared with the BM-MNCs group, the FL-MNCs transplantation group appears to have a more efficient platelet implantation effect in the HSCs transplantation recipient in vivo, as well as a higher platelet differentiation rate in vitro. This might be related to a higher proportion of megakaryocytes and higher expression levels of genes such as Mpl, Fog1, and Gata1 that could be important for platelet formation in FL-MNCs-CD41+cells. Further exploration of the specific functions of these genes and the characteristics of the different proportions of the donor cells will provide valuable clues for the future treatment of platelets reconstitution after HSCs transplantation clinically.


Asunto(s)
Plaquetas , Megacariocitos , Animales , Células de la Médula Ósea , Análisis Factorial , Hematopoyesis , Humanos , Hígado , Megacariocitos/metabolismo , Ratones , Ratones Endogámicos C57BL
3.
Poult Sci ; 99(10): 5149-5157, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32988554

RESUMEN

Improvac has been tentatively used to immune-castrate roosters. The aim of this study was to investigate whether Improvac affected skeletal muscle development in chickens. The muscle fiber type and size and the expression levels of genes related to muscle development in pectoral and thigh muscles were examined at 5, 9, and 14 wk of age in the control, early, late, and early + late Improvac-treated groups. Immunocastration with Improvac affected the development of thigh muscles and the expression of MYH1B, MSTN, and SM. The cross-sectional area in the early group was significantly larger than in the control group at the 14th week (P < 0.01). At the fifth week, the expression levels of MYH1B, MYOD, and MSTN in the early group were significantly higher than those in the control group (P < 0.05), and at the ninth week, the expression level of SM1 in the control group was significantly lower than that in early and late groups (P < 0.05). Immunocastration did not affect pectoral muscle development or the expression of genes related to muscle development.


Asunto(s)
Pollos , Desarrollo de Músculos , Músculo Esquelético , Orquiectomía , Animales , Pollos/crecimiento & desarrollo , Masculino , Desarrollo de Músculos/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Orquiectomía/veterinaria , Músculos Pectorales/efectos de los fármacos
4.
Poult Sci ; 98(11): 6034-6045, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31041439

RESUMEN

Immunocastration (vaccination against Gonadotropin-releasing hormone (GnRH)) has been regarded as a friendly substitution to physical castration in animals. To date, a few studies have reported the use of Improvac for immunocastration in boar and one study in broiler chickens; however, there is an apparent dearth of scientific evidence regarding the application of Improvac for immunocastration in birds. In the present study, we evaluated the effects of Improvac-based immunocastration on testosterone levels and spermatogenesis in broiler chickens and the effects of Improvac on the expression of genes related to testosterone biosynthesis and metabolism as well as spermatogenesis. The birds were randomly divided into 4 groups (n = 30 each): Control group (non-immunized), Early group (immunized with Improvac at week 3), Late group (immunized with Improvac at week 6), and Early + Late group (immunized with Improvac at weeks 3 and 6). Immunization with Improvac significantly improved the average daily gain compared to the Control group. Of note, following Improvac vaccination, the reproductive efficiency was significantly decreased in male broiler chickens. Furthermore, parameters such as the serum testosterone concentration, spermatogenesis, and the expression levels of genes related to testosterone metabolism (Cyp17A1, Cyp19, HSD3B1, and HSD17B3) and spermatogenesis (Cyclin A1 and Cyclin A2) were significantly reduced in the immunized groups compared to the Control group. Taken together, these findings reveal that immunization against GnRH can be achieved, at least partially, in male broiler chickens. The results of our study also support the hypothesis of using Improvac as an alternative solution to caponization, with considerably improved animal welfare.


Asunto(s)
Pollos/fisiología , Hormona Liberadora de Gonadotropina/administración & dosificación , Orquiectomía/veterinaria , Espermatogénesis/efectos de los fármacos , Vacunas/administración & dosificación , Animales , Pollos/crecimiento & desarrollo , Masculino , Orquiectomía/métodos , Distribución Aleatoria , Testosterona/sangre , Vacunación/veterinaria
5.
Eur Rev Med Pharmacol Sci ; 22(22): 7826-7831, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30536327

RESUMEN

OBJECTIVE: To investigate the function of microRNA-7-5p in human mesenchymal stem cells (hMSCs) and its underlying potential mechanism in osteogenic differentiation. PATIENTS AND METHODS: Expression levels of osteogenic genes (ALP, RUNX2), microRNA-7-5p and CMKLR1 in hMSCs were detected by quantitative real time-polymerase chain reaction (qRT-PCR). After transfection of microRNA-7-5p mimics or inhibitor, the effect of microRNA-7-5p on osteogenic differentiation of hMSCs was detected by Alizarin red staining, ALP activity determination and Western blot, respectively. The potential target gene of microRNA-7-5p was predicted online and further verified by luciferase reporter gene assay. Rescue experiments were conducted to explore whether the effect of microRNA-7-5p on osteogenic differentiation of hMSCs could be reversed by CMKLR1. RESULTS: Expression levels of ALP, RUNX2 and microRNA-7-5p were gradually elevated with the prolongation of osteogenic differentiation, whereas CMKLR1 was reduced. Overexpression of microRNA-7-5p increased levels of ALP and RUNX2. The amount of calcified nodules was increased after microRNA-7-5p overexpression. CMKLR1 was the target gene of microRNA-7-5p. The effect of microRNA-7-5p on osteogenic differentiation of hMSCs could be reversed by CMKLR1. CONCLUSIONS: MicroRNA-7-5p promotes osteogenic differentiation of hMSCs via targeting CMKLR1.


Asunto(s)
Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteogénesis/genética , Receptores de Quimiocina/metabolismo , Diferenciación Celular/genética , Humanos , Transfección
6.
Environ Sci Pollut Res Int ; 21(22): 13017-26, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24994107

RESUMEN

The aim of this study was to evaluate the effects of plant roots (Typha angustifolia roots) on the hydraulic performance during the clogging process from the perspective of time and space distributions in mesocosm vertical flow-constructed wetlands with coarse sand matrix. For this purpose, a pair of lab-scale experiments was conducted to compare planted and unplanted systems by measuring the effective porosity and hydraulic conductivity of the substrate within different operation periods. Furthermore, the flow pattern of the clogging process in the planted and unplanted wetland systems were evaluated by their hydraulic performance (e.g., mean residence time, short circuiting, volumetric efficiency, number of continuously stirred tank reactors, and hydraulic efficiency factor) in salt tracer experiments. The results showed that the flow conditions would change in different clogging stages, which indicated that plants played different roles related to time and space. In the early clogging stages, plant roots restricted the flow of water, while in the middle and later clogging stages, especially the later stage, growing roots opened new pore spaces in the substrate. The roots played an important role in affecting the hydraulic performance in the upper layer (0-30 cm) where the sand matrix had a larger root volume fraction. Finally, the causes of the controversy over plant roots' effects on clogging were discussed. The results helped further understand the effects of plant roots on hydraulic performance during the clogging process.


Asunto(s)
Raíces de Plantas/fisiología , Biodegradación Ambiental , Hidrodinámica , Porosidad , Typhaceae/fisiología , Eliminación de Residuos Líquidos/métodos , Purificación del Agua , Humedales
7.
J Int Med Res ; 38(6): 2153-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21227021

RESUMEN

The aim of this study was to explore the impact of depression mood disorder on the incidence of adverse drug reactions of anticancer drugs in cancer patients. The Hamilton Depression Scale 17 was used to evaluate the depression mood disorder level in 73 cancer patients before chemotherapy. Pharmacists monitored adverse drug reactions during the chemotherapy period. The relationship between depression mood disorder level and the incidence of adverse drug reactions was analysed. The frequency and extent of total adverse drug reactions were not related to depression mood disorder level. The frequency and extent of subjectively experienced adverse drug reactions such as anorexia, nausea and fatigue were related to depression mood disorder level. In conclusion, psychological support and intervention should be provided to cancer patients in order to improve patient adherence and cancer chemotherapy effectiveness, and to decrease the incidence of adverse drug reactions.


Asunto(s)
Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Trastorno Depresivo/complicaciones , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Adulto , Sistemas de Registro de Reacción Adversa a Medicamentos , Anciano , Trastorno Depresivo/etiología , Trastorno Depresivo/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Adulto Joven
8.
Theriogenology ; 56(4): 545-56, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11572436

RESUMEN

The production of valuable pharmaceutical proteins using transgenic animals as bioreactors has become one of the goals of biotechnology. However, the efficiency of producing transgenic animals by means of pronuclear microinjection is low. This may be attributed in part to the low integration rate of foreign DNA. Therefore, a large number of recipients are required to produce transgenic animals. We recently developed a transgenic procedure that combined the techniques of goat oocyte in vitro maturation (IVM), in vitro fertilization (IVF), microinjection, preimplantation selection of the transgenic embryos with nested PCR and transferring the transgenic embryos into the recipient goat uterus to produce transgenic goats. Thirty-seven transgenic embryos determined by nested PCR were transferred to thirty-two recipient goats. In the end, four live-born kids were produced. As predicted, all the live kids were transgenic as identified by PCR as well as Southern blot hybridization, The integration rate was 100% (4/4) which was completely in accordance with the results of embryo preimplantation detection. The results showed a significant decrease in the number of recipients required as only 8 recipients (32/4) were needed to obtain one live transgenic goat. We suggest that the transgenic system described herein may provide an improved way to efficiently produce transgenic goats on a large scale.


Asunto(s)
Animales Modificados Genéticamente/embriología , Transferencia de Embrión/veterinaria , Fertilización In Vitro/veterinaria , Cabras/embriología , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/fisiología , Animales Recién Nacidos , ADN/química , ADN/genética , Factor IX/biosíntesis , Femenino , Fertilización In Vitro/métodos , Cabras/genética , Cabras/fisiología , Masculino , Oocitos/fisiología , Reacción en Cadena de la Polimerasa , Embarazo
9.
Br J Haematol ; 111(1): 351-8, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11091224

RESUMEN

The antisense fragment targeting the aberrant splice sites of the beta-thalassaemia allele, IVS-2-654 C-->T (beta654), pretranscript was cloned into the mammalian expression vector, pcDNA3. The recombinant construct, pCMVA, was then used to repair the defective splicing of the beta654 mutant pretranscript in cultured beta654 erythroid cells by the lipofectin-mediated DNA transfection method. The total RNA was extracted at given time points after transfection and the effect of antisense RNA was studied by reverse transcription polymerase chain reaction (RT-PCR)-mediated mRNA quantitative assay, as well as globin chain microbiosynthesis. The antisense fragment transcribed from pCMVA effectively improved the beta654 splicing pattern in cultured erythroid cells. The level of correctly spliced transcript increased from 0.19 (day 0 after transfection) to 0.58 (day 8) in beta654/beta654 homozygous erythroid cells, and from 0.45 (day 0) to 0.83 (day 8) in beta654/betaA heterozygous erythroid cells, as determined by the ratio of normally spliced beta-globin transcript over total beta-globin transcript. Correspondingly, the ratios of globin chain biosynthesis (beta/alpha) increased from 0.16 (day 0) to 0.52 (day 8) in beta654/beta654 erythroid cells, and from 0.39 (day 0) to 0.84 (day 8) in beta654/betaA erythroid cells. Antisense RNA had no significant effect on the splicing pattern in betaA/betaA erythroid cells. The splicing pattern in transfected cells with pCMVA showed significant changes compared with that in untransfected cells and that in transfected cells with the control antisense fragment (human SRY gene sequence). In addition, we did not observe side-effects on cytological features after the introduction of pCMVA. All these results indicated that the antisense RNA transcribed from the mammalian expression vector pCMVA could efficiently and specifically suppress the aberrant splicing pattern of beta654 mutant pretranscript and restore the correct splicing pathway in vivo, leading to the improvement of globin chain biosynthesis in thalassaemic cells.


Asunto(s)
Células Precursoras Eritroides , Terapia Genética/métodos , Empalme del ARN , ARN sin Sentido , Transfección/métodos , Talasemia beta/terapia , Adulto , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Talasemia beta/genética
10.
Yi Chuan Xue Bao ; 27(7): 573-9, 2000.
Artículo en Chino | MEDLINE | ID: mdl-11051717

RESUMEN

The mammary gland expression vector (pcDNA 3.1-GCALBm) containing the full-length sequence of human serum albumin (hALB) cDNA and intron 1 as well as the goat beta-casien gene promoter and 5' up-stream regulatory sequence was constructed. The vector was micro-injected into bovine IVF eggs. The embryos were in vitro cultured to the late stage of morulae, and then few embryo cells were aspirated for the implantation detection of target gene integration and SRY DNA sequence using nested-PCR. Afterwards, ten integrated embryos were selected to transfer into eight recipients and three were pregnant. The pregnant rate was 37.5%(3/8). However, two were miscarried in mid-trimester but one was pregnant at term to deliver a male transgenic cattle integrated with hALB mini-gene. The transgenic efficiency was 12.5% (1/8).


Asunto(s)
Bovinos/genética , Fertilización In Vitro , Transferencia de Gen Horizontal , Albúmina Sérica/genética , Animales , Animales Modificados Genéticamente , Femenino , Humanos , Masculino , Técnicas de Cultivo de Órganos , Embarazo
11.
Acta Haematol ; 102(1): 1-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10473880

RESUMEN

Increased levels of hemoglobin A(2) (HbA(2)) are present in most beta-thalassemia carriers. The mechanism of this effect is not understood, although the increase may result from transcriptional and posttranscriptional changes. In the present study, we quantitate delta-globin mRNA levels in peripheral-blood-enriched reticulocytes and characterize the variation of delta-mRNA levels in 30 beta-thalassemia heterozygotes who individually carry one of the four common Chinese beta-thalassemia alleles [codons 41/42 (-TTCT); codon 17 (A-->T); IVS-II-654 (C-->T); -28 (A-->G)]. A sensitive and quantitative competitive reverse-transcriptase polymerase chain reaction method was developed and used to assess the absolute amounts of delta-mRNA transcripts in these peripheral erythroid cells. The results showed a large increase in delta-mRNA amounts in all the carriers examined (72.3 +/- 9.0 amol/microg RNA) as compared with those in 12 controls (1.2 +/- 0.2 amol/ microg RNA). There was a direct correlation between the delta-mRNA levels and types of beta-thalassemia alleles; generally, the delta-mRNA levels are higher in heterozygotes for beta(0)-thalassemia mutations than beta(+)-thalassemia mutations. The delta-mRNA levels correlated inversely with hemoglobin and red cell indices but directly with HbA(2) levels in heterozygotes of each of the group of beta-thalassemia mutations. These results suggest that a greater impairment in beta-globin gene expression results in increased transcription of delta-globin gene and in a higher level of HbA(2).


Asunto(s)
Pueblo Asiatico/genética , Tamización de Portadores Genéticos , Globinas/genética , ARN Mensajero/metabolismo , Talasemia beta/genética , Niño , Codón , Humanos , Modelos Lineales , Mutación , Reticulocitos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Hemoglobin ; 23(1): 57-67, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10081986

RESUMEN

Hb G-Coushatta [beta22(B4)Glu-->Ala] is found in geographically separated ethnic groups. Commonest along the Silk Road region of China but also present in the North American Coushatta, we sought to determine whether this variant had a unicentric or multicentric origin. We examined the haplotype of the beta-globin gene cluster in two Chinese families and in five Louisiana Coushatta heterozygous for this mutation. Chinese and Louisiana Coushatta had different haplotypes associated with the identical Hb G mutation. These haplotypes were defined by the presence of a HindIII restriction site in the Agamma-globin gene and AvaII restriction site in the beta-globin gene in Chinese subjects and their absence in the Louisiana Coushatta. We found a CAC at codon beta2 (beta-globin gene framework 1 or 2) linked to the Hb G-Coushatta gene in Chinese, and a CAT (framework 3) in Louisiana Coushatta, indicating different beta-globin gene frameworks. Both the Hb G-Coushatta mutation (GAA-->GCA) and the codon 2 CAC-->CAT polymorphism are normal delta-globin gene sequences, suggesting the possibility of gene conversion. We conclude that Hb G-Coushatta had at least two independent origins. This could be due to separate mutations at codon beta22 in Chinese and Louisiana Coushatta, a mutation at this codon and a beta-->delta conversion, or two beta-->delta gene conversion events.


Asunto(s)
Hemoglobinas Anormales/genética , China , Femenino , Globinas/genética , Haplotipos , Humanos , Louisiana , Masculino , Familia de Multigenes , Mutación , Linaje
13.
Hematopathol Mol Hematol ; 10(1-2): 63-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8792148

RESUMEN

Hemophilia A is an X-linked bleeding disorder caused by deleterious mutations in the factor VIII gene. An inversion caused by introchromosomal homologous recombination between the A gene located in intron 22 of the factor VIII gene and one of the two telomeric A genes has been recently described as the common cause of about 50% of cases of severe hemophilia A. The rearrangement can be readily detected by a Southern blotting procedure. We report use of this procedure to detect rearrangements in 106 unrelated Chinese hemophilia A cases. In 49.3% of the patients with severe disease an inversion was found, but no inversion was detected in any of the patients with moderate or mild disease. The majority of inversions (91.4%) involved the most distal A gene; in a minority (8.6%) the more proximal A gene was involved. These results indicate that intron 22 inversion is the most important molecular defect causing Chinese hemophilia A and that analysis for intron 22 inversion may be the first-line test in the molecular diagnosis of severe hemophilia A.


Asunto(s)
Pueblo Asiatico/genética , Inversión Cromosómica , Factor VIII/genética , Pruebas Genéticas/métodos , Hemofilia A/diagnóstico , Southern Blotting , China , Reordenamiento Génico , Hemofilia A/genética , Humanos , Masculino
14.
Hematology ; 1(3): 253-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-27406620

RESUMEN

Combining allele-specific amplification (ASPCR) with multiplex PCR, we developed a new approach-multiplex allele-specific amplification (MASPCR) to detect five common types of ß-thalassemia mutations (CD 41-42(-4bp), CD 17 A→T, CD 71-72 (+ A), -28 A→ G and IVS-2-654 C→ T) which account for approximately 80% of all ß-thalassemia alleles in Chinese individuals. Using this technique, prenatal diagnoses were performed for ten pregnancies at risk for ß-thalassemia. All the results were confirmed by PCR/ASO probe hybridization or DNA sequencing. This study suggests that this method is a simple, accurate approach that may further improve the prevention programs for ß-thalassemia that have already dramatically lowered the birth rate of affected children in some parts of the world.

16.
Br J Haematol ; 90(3): 557-63, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7646994

RESUMEN

The beta-thalassaemias represent a heterogenous group of diseases resulting from decreased erythroid beta-globin mRNA expression and imbalanced alpha/beta-globin chain synthesis which are manifest clinically by ineffective erythropoiesis and excessive haemolysis. Increasing levels of haemoglobin F (HbF) by pharmacological agents has been proposed to ameliorate the severity of the disease by improving the balance in globin chain synthesis. Hydroxyurea (HU), as an effective agent with low toxicity for activating gamma-globin gene, has been shown to enhance HbF synthesis in experimental animals and in patients with sickle cell anaemia. However, previous trials of HU in beta-thalassaemia patients are ambiguous, with a small number having increased HbF synthesis. In a recent study of HU effects in Chinese beta-thalassaemia patients we unexpectedly found that two unrelated patients with beta-thalassaemia intermedia demonstrated an improvement in the effectiveness of erythropoiesis reflected by an increase in haemoglobin concentration (from 4.1 to 6.3 g/dl, patient 1; from 6.5 to 9.7 g/dl, patient 2) and in red cell volume (from 68 to 104 fl, patient 1; from 68 to 85 fl, patient 2) after a period of excess of 300d of low-dosage HU treatment. These effects, however, appear to be due to increased beta-globin biosynthesis, because the percentage of HbF decreased in each patient as total Hb increased. This was reflected by changes in the beta/alpha ratio (from 0.301 to 0.581, patient 1; from 0.348 to 0.487, patient 2) with minimal changes in gamma-globin biosynthesis. We conclude that in addition to its known effects in stimulating gamma-globin production, hydroxyurea may have a more general role in augmenting globin synthesis, including beta-globin in some thalassaemia intermedia patients who maintain the capacity to express normal beta-globin chains.


Asunto(s)
Globinas/biosíntesis , Hidroxiurea/uso terapéutico , Talasemia beta/tratamiento farmacológico , Femenino , Hemoglobinas/análisis , Humanos , Hidroxiurea/efectos adversos , Recuento de Leucocitos , Masculino , Recuento de Plaquetas , Recuento de Reticulocitos , Talasemia beta/metabolismo
17.
Br J Haematol ; 88(3): 541-6, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7819066

RESUMEN

IVS-2-654 C-->T is a common Chinese beta-thalassaemia mutation. Previous studies report that this mutation resulted in the formation of an abnormally spliced mRNA and the absence of detectable normal beta-globin mRNA, hence the mutation was considered to cause beta o-thalassaemia. We recently used the method of PCR amplified cDNA copies of circulating erythroid cell mRNA to analyse the mutant gene transcripts and found that this IVS-2-654 mutation does not abolish normal RNA processing entirely, but that a significant amount (over 15%) of normally processed beta-globin mRNA is produced. Microglobin chain biosynthetic analysis using the HPLC method showed that beta-globin chain was also present in the blood of patients with IVS-2-654 C-->T mutation. Accordingly, this mutant allele leads to a beta (+)-thalassaemia. Further, the methodology described in this paper provides a new approach towards the detection of RNA transcripts of beta-thalassaemia alleles as well as the study of gene expression in beta-thalassaemia and other genetic diseases.


Asunto(s)
Globinas/genética , Mutación , Talasemia beta/genética , Alelos , Secuencia de Bases , Preescolar , Cromatografía Líquida de Alta Presión , Eritrocitos/fisiología , Expresión Génica , Humanos , Linfocitos/fisiología , Masculino , Datos de Secuencia Molecular , ARN Mensajero/análisis
18.
Sci China B ; 37(11): 1350-9, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7865126

RESUMEN

A newly developed method of RT-PCR/competitive PCR for measuring the relative and absolute content of globin mRNAs as well as micro-globin chain biosynthetic assay have been used to study the alterations of globin gene expressions in the patients with beta-thalassemia pre- and post-hydroxyurea (HU) treatment. It was found for the first time that HU had the effect of enhancing beta-globin gene expression in some patients. Two cases with beta-thalassemia who were subjected to HU treatment for over two years showed a marked increase in beta-globin mRNA level and beta-globin chain synthesis, resulting in more effective erythropoiesis and the alleviation of clinical symptoms.


Asunto(s)
Globinas/genética , Hidroxiurea/uso terapéutico , ARN Mensajero/metabolismo , Talasemia beta/tratamiento farmacológico , Adulto , Niño , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Hemoglobinas/metabolismo , Humanos , Hidroxiurea/farmacología , Masculino , Persona de Mediana Edad , Talasemia beta/genética
19.
Sci China B ; 37(2): 170-6, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8068189

RESUMEN

This study analyses the bovine SRY DNA sequence by direct sequencing procedure, followed by the designation of the PCR primers specific for bovine SRY. Using PCR amplification of bovine SRY gene, the embryo sex was determined. The results of the embryo sex identification were confirmed after the embryo transfer and pregnancies.


Asunto(s)
ADN/genética , Análisis para Determinación del Sexo , Cromosoma Y , Animales , Secuencia de Bases , Bovinos , Transferencia de Embrión , Femenino , Masculino , Reacción en Cadena de la Polimerasa
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