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1.
Planta ; 260(4): 92, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261328

RESUMO

MAIN CONCLUSION: The Ustilaginoidea virens -rice pathosystem has been used as a model for flower-infecting fungal pathogens. The molecular biology of the interactions between U. virens and rice, with an emphasis on the attempt to get a deeper comprehension of the false smut fungus's genomes, proteome, host range, and pathogen biology, has been investigated. Meta-QTL analysis was performed to identify potential QTL hotspots for use in marker-assisted breeding. The Rice False Smut (RFS) caused by the fungus Ustilaginoidea virens currently threatens rice cultivators across the globe. RFS infects rice panicles, causing a significant reduction in grain yield. U. virens can also parasitize other hosts though they play only a minor role in its life cycle. Furthermore, because it produces mycotoxins in edible rice grains, it puts both humans and animals at risk of health problems. Although fungicides are used to control the disease, some fungicides have enabled the pathogen to develop resistance, making its management challenging. Several QTLs have been reported but stable gene(s) that confer RFS resistance have not been discovered yet. This review offers a comprehensive overview of the pathogen, its virulence mechanisms, the genome and proteome of U. virens, and its molecular interactions with rice. In addition, information has been compiled on reported resistance QTLs, facilitating the development of a consensus genetic map using meta-QTL analysis for identifying potential QTL hotspots. Finally, this review highlights current developments and trends in U. virens-rice pathosystem research while identifying opportunities for future investigations.


Assuntos
Interações Hospedeiro-Patógeno , Hypocreales , Oryza , Doenças das Plantas , Locos de Características Quantitativas , Oryza/microbiologia , Doenças das Plantas/microbiologia , Hypocreales/patogenicidade , Hypocreales/genética , Hypocreales/fisiologia , Virulência/genética , Locos de Características Quantitativas/genética , Resistência à Doença/genética , Genoma Fúngico
2.
Mol Biol Rep ; 51(1): 426, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498081

RESUMO

BACKGROUND: Drought stress is considered as one of the major production constraints in rice. RPHR-1005R is a restorer line (R-Line) with a popular, medium-slender grain type, and is the male parent of the popular Indian rice hybrid, DRR-H3. However, both the hybrid and its restorer are highly vulnerable to the drought stress, which limits the adoption of the hybrid. Therefore, the selection of the restorer line RPHR-1005R has been made with the objective of enhancing drought tolerance. METHODS AND RESULTS: In this study, we have introgressed a major QTL for grain yield under drought (qDTY 1.1) from Nagina22 through a marker-assisted backcross breeding (MABB) strategy. PCR based SSR markers linked to grain yield under drought (qDTY1.1 - RM431, RM11943), fertility restorer genes (Rf3-DRRM-Rf3-10, Rf4-RM6100) and wide compatibility (S5n allele) were deployed for foreground selection. At BC2F1, a single plant (RPHR6339-4-16-14) with target QTL in heterozygous condition and with the highest recurrent parent genome recovery (85.41%) and phenotypically like RPHR-1005R was identified and selfed to generate BC2F2. Fifty-eight homozygous lines were advanced to BC2F4 and six promising restorer lines and a hybrid combination (APMS6A/RPHR6339-4-16-14-3) were identified. CONCLUSIONS: In summary, the six improved restorer lines could be employed for developing heterotic hybrids possessing reproductive stage drought tolerance. The hybrid combination (APMS6A/RPHR6339-4-16-14-3) was estimated to ensure stable yields in drought-prone irrigated lowlands as well as in directly seeded aerobic and upland areas of India.


Assuntos
Resistência à Seca , Oryza , Oryza/genética , Melhoramento Genético , Melhoramento Vegetal , Reprodução , Grão Comestível/genética
3.
Planta ; 256(5): 87, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149531

RESUMO

MAIN CONCLUSION: Genomic selection and its importance in crop breeding. Integration of GS with new breeding tools and developing SOP for GS to achieve maximum genetic gain with low cost and time. The success of conventional breeding approaches is not sufficient to meet the demand of a growing population for nutritious food and other plant-based products. Whereas, marker assisted selection (MAS) is not efficient in capturing all the favorable alleles responsible for economic traits in the process of crop improvement. Genomic selection (GS) developed in livestock breeding and then adapted to plant breeding promised to overcome the drawbacks of MAS and significantly improve complicated traits controlled by gene/QTL with small effects. Large-scale deployment of GS in important crops, as well as simulation studies in a variety of contexts, addressed G × E interaction effects and non-additive effects, as well as lowering breeding costs and time. The current study provides a complete overview of genomic selection, its process, and importance in modern plant breeding, along with insights into its application. GS has been implemented in the improvement of complex traits including tolerance to biotic and abiotic stresses. Furthermore, this review hypothesises that using GS in conjunction with other crop improvement platforms accelerates the breeding process to increase genetic gain. The objective of this review is to highlight the development of an appropriate GS model, the global open source network for GS, and trans-disciplinary approaches for effective accelerated crop improvement. The current study focused on the application of data science, including machine learning and deep learning tools, to enhance the accuracy of prediction models. Present study emphasizes on developing plant breeding strategies centered on GS combined with routine conventional breeding principles by developing GS-SOP to achieve enhanced genetic gain.


Assuntos
Melhoramento Vegetal , Seleção Genética , Genoma de Planta/genética , Genômica , Fenótipo
4.
Sci Rep ; 14(1): 16458, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013915

RESUMO

Rice blast disease is the most devastating disease constraining crop productivity. Vertical resistance to blast disease is widely studied despite its instability. Clusters of genes or QTLs conferring blast resistance that offer durable horizontal resistance are important in resistance breeding. In this study, we aimed to refine the reported QTLs and identify stable meta-QTLs (MQTLs) associated with rice blast resistance. A total of 435 QTLs were used to project 71 MQTLs across all the rice chromosomes. As many as 199 putative rice blast resistance genes were identified within 53 MQTL regions. The genes included 48 characterized resistance gene analogs and related proteins, such as NBS-LRR type, LRR receptor-like kinase, NB-ARC domain, pathogenesis-related TF/ERF domain, elicitor-induced defense and proteins involved in defense signaling. MQTL regions with clusters of RGA were also identified. Fifteen highly significant MQTLs included 29 candidate genes and genes characterized for blast resistance, such as Piz, Nbs-Pi9, pi55-1, pi55-2, Pi3/Pi5-1, Pi3/Pi5-2, Pikh, Pi54, Pik/Pikm/Pikp, Pb1 and Pb2. Furthermore, the candidate genes (42) were associated with differential expression (in silico) in compatible and incompatible reactions upon disease infection. Moreover, nearly half of the genes within the MQTL regions were orthologous to those in O. sativa indica, Z. mays and A. thaliana, which confirmed their significance. The peak markers within three significant MQTLs differentiated blast-resistant and susceptible lines and serve as potential surrogates for the selection of blast-resistant lines. These MQTLs are potential candidates for durable and broad-spectrum rice blast resistance and could be utilized in blast resistance breeding.


Assuntos
Resistência à Doença , Redes Reguladoras de Genes , Oryza , Doenças das Plantas , Locos de Características Quantitativas , Oryza/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Cromossomos de Plantas/genética , Mapeamento Cromossômico , Genes de Plantas
5.
Nat Genet ; 34(1): 59-64, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12669066

RESUMO

Most eukaryotic cell types use a common program to regulate the process of cell division. During mitosis, successful partitioning of the genetic material depends on spatially coordinated chromosome movement and cell cleavage. Here we characterize a zebrafish mutant, retsina (ret), that exhibits an erythroid-specific defect in cell division with marked dyserythropoiesis similar to human congenital dyserythropoietic anemia. Erythroblasts from ret fish show binuclearity and undergo apoptosis due to a failure in the completion of chromosome segregation and cytokinesis. Through positional cloning, we show that the ret mutation is in a gene (slc4a1) encoding the anion exchanger 1 (also called band 3 and AE1), an erythroid-specific cytoskeletal protein. We further show an association between deficiency in Slc4a1 and mitotic defects in the mouse. Rescue experiments in ret zebrafish embryos expressing transgenic slc4a1 with a variety of mutations show that the requirement for band 3 in normal erythroid mitosis is mediated through its protein 4.1R-binding domains. Our report establishes an evolutionarily conserved role for band 3 in erythroid-specific cell division and illustrates the concept of cell-specific adaptation for mitosis.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/deficiência , Proteína 1 de Troca de Ânion do Eritrócito/genética , Eritropoese/genética , Mitose/genética , Mutação , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Sequência de Aminoácidos , Anemia Diseritropoética Congênita/genética , Animais , Animais Geneticamente Modificados , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Hibridização in Situ Fluorescente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Fenótipo , Peixe-Zebra/sangue
6.
J Indian Prosthodont Soc ; 13(2): 122-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24431721

RESUMO

With the advent of newer indirect composite resin materials for crown and bridge prosthesis, it has become imperative to evaluate their strength to serve as long term replacements as a substitute to metal ceramic restorations. This study aimed to evaluate and compare the flexural bond strength of three composite resin veneering material to metal, cured by different methods. Specimen were fabricated with pattern resin by duplicating it with machined metal die and divided into three groups. Three composite resin materials were used in this study. Group (A) received Adoro, Group (B) received Targis and Group (C) received Tescera. The bond strength of all specimens was tested with Lloyd's universal testing machine under three point loading. The highest values for fracture resistance were displayed by light, heat and pressure cured composites followed by composites cured using a temperature of 104 °C and composites with curing temperature of 95 °C. The results indicate that there is a significant difference between the three groups, with the Tescera group specimens exhibiting the highest flexural bond strength. Of the other two groups, Adoro group exhibited higher flexural bond strength than Targis group. The results of this study suggest that Tescera group with curing temperature of 130 °C and pressure of 80 Psi, cured with metal halide unit exhibited the highest flexural bond strength when compared to Adoro and Targis groups.

7.
Int J Pharm ; 644: 123339, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37611853

RESUMO

VO(IV) complex is little toxic and highly effective than vanadium salts. A vanadyl metal complex from 8-formyl-7-hydroxy-4-methyl coumarin derivative has been synthesized and functionalized with copper nanoparticles. The Spectrochemical studies such as UV, FTIR, 1NMR and ESR spectra were recorded to characterize the ligand(CUAP), Vanadyl complex[VO(CUAP)SO4] and nano Cu-VO(IV)complex efficiently. The structural studies of vanadyl complex confirmed that the ligand coordinate with metal through nitrogen atom of azomethine, carbonyl oxygen and phenolic oxygen. ESR spectrum of vanadyl complex revealed the covalent nature. XRD pattern of nano Cu-VO(IV) complex indicated the crystalline nature and the average particle size was 20.91 nm. SEM image of nano Cu-VO(IV) complex showed that the nano particles accumulated to form spherical shaped particles. The particle size obtained from Transmission Electron Microscopy of nano functionalized metal complex is âˆ¼ 20 nm. It is closely matched to the particle size calculated from XRD results. Fluorescence of vanadyl complex and nano Cu-VO(IV) complex exhibit the emission from 270 to 900 nm range with significant fluorescence at âˆ¼ 750 nm. The DNA cleavage of all the compounds was evaluated using Agarose gel electrophoresis technique and showed greater cleavage of vanadyl complex. The anticancer activity of compounds was carried out against two cancer cell lines viz Human Breast Cancer Cell line (MCF-7) and Human Leukemia Cancer Cell Line(K-562). Oxovanadium complex exhibited good anticancer activities than ligand and nano-functionalized complex. The antidiabetic activities of vanadyl and nano functionalized complexes were studied against α-Amylase and ß-Glucosidase inhibition assay. In this study vanadyl complex showed higher inhibition activity on α-Amylase compared with standard Acarbose. The bioimaging of nano-functionalized metal complex showed high fluorescent properties. The molecular docking study of ligand and vanadyl complex showed greater docking results with CDK2 receptor.


Assuntos
Complexos de Coordenação , Hipoglicemiantes , Humanos , Clivagem do DNA , Ligantes , Simulação de Acoplamento Molecular , Vanadatos/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia
8.
J Appl Genet ; 63(2): 185-197, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34841470

RESUMO

Late wilt disease (LWD) caused by Harpophora maydis (Samra, Sabet and Hing) is emerging as major production constraint in maize across the world. As a prelude to develop maize hybrid resistance to LWD, genetic basis of resistance was investigated. Two F2:3 mapping populations (derived from CV156670 × 414-33 (P-1) and CV156670 × CV143587 (P-2)) were challenged with LWD at two locations (Kallinayakanahalli and Muppadighatta) during 2017 post-rainy season. A wider range of LWD scores was observed at both locations in both the populations. LWD response was influenced by significant genotype × location interaction. Six and 56 F2:3 progeny families showed resistance level better than resistant parent. A total of 150 and 199 polymorphic single nucleotide polymorphism markers were used to genotype P-1 and P-2, respectively. Inclusive composite interval mapping was performed to detect significant Quantitative Trait Loci (QTL), QTL × QTL, QTL × location interaction effects. Three major and four minor QTL controlling LWD resistance were detected on chromosome-1. The position and effect of the QTL varied with the location. Significant di-QTL interactions involving QTL (with significant and/or non-significant effects) located within and between all the ten chromosomes were detected. Five of the seven detected QTL showed significant QTL × location interaction. Though two major QTL (q-lw-1.5 and q-lw-1.6) with lower Q×L interaction effects could be considered as stable, their phenotypic variance is not large enough to deploy them in Marker Assisted Selection (MAS). However, these QTL are of paramount importance in accumulating positive alleles for LWD resistance breeding.


Assuntos
Ascomicetos , Resistência à Doença , Doenças das Plantas , Zea mays , Ascomicetos/patogenicidade , Mapeamento Cromossômico , Resistência à Doença/genética , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Locos de Características Quantitativas , Zea mays/genética , Zea mays/microbiologia
9.
Sci Rep ; 12(1): 13832, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35974066

RESUMO

Quantitative trait loci (QTL) for rice grain weight identified using bi-parental populations in various environments were found inconsistent and have a modest role in marker assisted breeding and map-based cloning programs. Thus, the identification of a consistent consensus QTL region across populations is critical to deploy in marker aided breeding programs. Using the QTL meta-analysis technique, we collated rice grain weight QTL information from numerous studies done across populations and in diverse environments to find constitutive QTL for grain weight. Using information from 114 original QTL in meta-analysis, we discovered three significant Meta-QTL (MQTL) for grain weight on chromosome 3. According to gene ontology, these three MQTL have 179 genes, 25 of which have roles in developmental functions. Amino acid sequence BLAST of these genes indicated their orthologue conservation among core cereals with similar functions. MQTL3.1 includes the OsAPX1, PDIL, SAUR, and OsASN1 genes, which are involved in grain development and have been discovered to play a key role in asparagine biosynthesis and metabolism, which is crucial for source-sink regulation. Five potential candidate genes were identified and their expression analysis indicated a significant role in early grain development. The gene sequence information retrieved from the 3 K rice genome project revealed the deletion of six bases coding for serine and alanine in the last exon of OsASN1 led to an interruption in the synthesis of α-helix of the protein, which negatively affected the asparagine biosynthesis pathway in the low grain weight genotypes. Further, the MQTL3.1 was validated using linked marker RM7197 on a set of genotypes with extreme phenotypes. MQTL that have been identified and validated in our study have significant scope in MAS breeding and map-based cloning programs for improving rice grain weight.


Assuntos
Oryza , Locos de Características Quantitativas , Asparagina/genética , Grão Comestível/genética , Estudos de Associação Genética , Oryza/genética , Fenótipo , Melhoramento Vegetal
10.
J Appl Genet ; 62(4): 571-583, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34247322

RESUMO

As a prelude to exploit DNA methylation-induced variation, we hypothesized the existence of substantial natural DNA methylation variation and its association with economically important traits in dolichos bean, and tested it using amplified methylation polymorphism-polymerase chain reaction (AMP-PCR) assay. DNA methylation patterns such as internal, external, full and non-methylation were amplified in a set of 64 genotypes using 26 customized randomly amplified polymorphic DNA (RAPD) primers containing 5'CCGG3' sequence. The 64 genotypes included 60 germplasm accessions (GA), two advanced breeding lines (ABLs) and two released varieties. The ABLs and released varieties are referred to as improved germplasm accessions (IGA) in this study. The association of DNA methylation patterns with economically important traits such as days to 50% flowering, raceme length, fresh pods plant-1, fresh pod yield plant-1 and 100-fresh seed weight was explored. At least 50 genotypes were polymorphic for DNA methylation patterns at 10 loci generated by seven of the 26 RAPD primers. The GA and IGA differed significantly for total, full and external methylation and the frequency of methylation was higher in GA compared to that in IGA. The genotypes with external methylation produced longer racemes than those with full, internal and non-methylation in that order at polymorphic RAPD-11-242 locus. High pod yielding genotypes had significantly lower frequency of full methylation than low yielding ones. On the contrary, the genotypes that produced heavier fresh seeds harboured higher frequencies of total and externally methylated loci than those that produced lighter fresh seeds.


Assuntos
Dolichos , Metilação de DNA , Variação Genética , Melhoramento Vegetal , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico
11.
J Clin Diagn Res ; 11(7): ED27-ED28, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28892916

RESUMO

Malignant pilomatricoma is an extremely rare tumour arising from the hair follicle. About 80 known cases are reported in literature till date. Presented herewith are two cases of malignant pilomatricoma, occurring in young female patients, each with a different clinical presentation and outcome. It is important to be aware of this entity as malignant pilomatricoma, though, initially locally aggressive, can recur if incompletely excised and also can metastasize to lungs, bones and lymph nodes.

12.
J Nat Sci Biol Med ; 6(2): 449-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26283850

RESUMO

Mandibular deviation is multifactorial defect and its severity is based on the extent of osseous and soft tissue involvement, degree of tongue impaired, the loss of sensory and motor innervations, the type of wound closure, the presence of remaining natural teeth and finally the first initiation of prosthetic treatment. We describe a case of prosthetic management of a maxillary partially edentulous patient with hemimandibulectomy who reported after 4 years of postsurgical cancer therapy. A simple maxillary guided hollow inclined plane with twin occlusion acrylic prosthesis was fabricated as a functional training device to correct mandibular deviation, restore maxillomandibular relation and occlusal approximation. The patient was able to functionally achieve good maxillomandibular occlusal approximation with guidance therapy combined with physiotherapy in 2 weeks. A 6 months follow-up revealed patient satisfactory appreciation by understanding the limitations of overall prosthetic rehabilitation.

13.
Eur J Haematol ; 78(1): 72-81, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17042771

RESUMO

OBJECTIVES: The effects of prolonged macrophage depletion on haematological parameters were investigated in aged rats and compared with those in young ones. METHODS: Four weekly i.v. injections of dichloromethylene diphosphonate-containing liposomes (Cl2MDP-CL) were employed to achieve a prolonged depletion of bone marrow (BM) and spleen macrophages. The number of BM macrophages was then assessed by flow cytometry, whereas the spleen clearance function was judged by the elimination of oxidised red blood cells (RBC). Haematological parameters and signs of RBC ageing (reduced MCV, increased density and augmented 4.1a/4.1b membrane protein ratio) were determined. Finally, the recovery from phlebotomy-induced acute anaemia was investigated. RESULTS: Following the Cl2MDP-CL treatment, in comparison with young rats, the aged animals showed: (i) reduced numbers of BM macrophages; (ii) greater impairment of spleen clearance function; (iii) similar anaemic condition and signs of RBC ageing; (iv) greater increase in white blood cell (WBC) numbers (mainly neutrophils). In addition, whereas aged control rats showed a recovery from phlebotomy-induced acute anaemia which was similar to that of the untreated young animals, in the aged-treated rats, a significantly diminished/delayed restoration of RBC, Hb and reticulocyte to normal values was observed, accompanied by a significantly higher increase in WBC numbers than in the other groups of animals. CONCLUSION: Haematological abnormalities because of Cl2MDP-CL-induced macrophage depletion are potentiated in aged rats in which the BM regenerative potential of the erythroid lineage as well as the clearance function of the spleen appear compromised. Thus, in aged rats, macrophage dysfunction is likely to interfere with erythroid homeostasis particularly during haemopoietic stress.


Assuntos
Envelhecimento/patologia , Células Precursoras Eritroides/patologia , Macrófagos/patologia , Fatores Etários , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Contagem de Células , Difosfonatos/administração & dosagem , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Células Precursoras Eritroides/efeitos dos fármacos , Eritropoese/efeitos dos fármacos , Citometria de Fluxo , Injeções Intravenosas , Leucócitos/efeitos dos fármacos , Leucócitos/patologia , Macrófagos/efeitos dos fármacos , Metano/administração & dosagem , Flebotomia/efeitos adversos , Ratos , Ratos Wistar , Sensibilidade e Especificidade , Baço/efeitos dos fármacos , Baço/patologia
14.
Br J Haematol ; 131(4): 431-46, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16281933

RESUMO

The congenital dyserythropoietic anaemias (CDAs) are a heterogeneous group of diseases in which the anaemia is predominantly caused by dyserythropoiesis and marked ineffective erythropoiesis; three major (types I, II and III) and several minor subgroups have been identified. Additional information on the natural history of these conditions, the beneficial role of splenectomy in CDA type II and efficacy of interferon-alpha in type I have recently been reported. A disease gene has been localised to a chromosomal segment in the three major types and in CDA type I, a disease gene has been identified (CDANI). Mutations have been detected in both familial and sporadic cases but the predicted protein structure gives few clues as to its function. In both type I and II, there are cases unlinked to the identified localisations, suggesting genetic heterogeneity.


Assuntos
Anemia Diseritropoética Congênita/diagnóstico , Anemia Diseritropoética Congênita/sangue , Anemia Diseritropoética Congênita/genética , Anemia Diseritropoética Congênita/terapia , Medula Óssea/patologia , Diagnóstico Diferencial , Glicoproteínas/genética , Humanos , Mutação , Proteínas Nucleares
15.
Eur J Haematol ; 75(5): 406-16, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16191091

RESUMO

OBJECTIVES: To investigate whether macrophage-depleted rats may serve as a model for studying red blood cell (RBC) aging. METHODS: Rats were macrophage-depleted by 4 weekly injections of dichloromethylene diphosphonate-containing liposomes (Cl2MDP-CL). The macrophage content of spleens and bone marrows (BMs) was investigated by immunohistochemistry and light microscopy and by flow cytometry, respectively, after staining with macrophage-specific monoclonal antibodies. In addition, the ultrastructure of residual BM macrophages and their ability to phagocytose zymosan was studied. BM was also studied for apoptosis (by the TUNEL reaction) and for erythroid progenitor cell content. Furthermore, RBC indices, morphology, life span (by 51Cr labeling) and aging features (MCV, density, 4.1a/4.1b membrane protein ratio, anti-spectrin IgG binding, microvesiculation) were investigated. Serum TNF-alpha, iron, total iron-binding capacity (TIBC) and ferritin were also determined. RESULTS: Prolonged treatment with Cl2MDP-CL caused an almost complete depletion of macrophages in the spleen and a 58% reduction of those in the BM; the residual BM macrophages were activated as judged by their ultrastructure and phagocytic capacity in vitro. These alterations were accompanied by an increase in RBC life span and age-related RBC changes, as well as by mild anemia associated with a reduced reticulocyte count, reduced BM erythroid progenitors, increased numbers of apoptotic cells in the BM, low serum iron, high TIBC and increased serum TNF-alpha levels. CONCLUSIONS: Rats subjected to prolonged macrophage depletion showed an increased prevalence of senescent RBC in the circulation due to their impaired clearance by macrophages. Hence, these animals provide a model system in which mechanisms of RBC aging can be delineated. They also showed impaired erythropoiesis, presumably related to a reduction in BM macrophages and increased production of proinflammatory cytokines by residual activated marrow macrophages and other cells.


Assuntos
Ácido Clodrônico/administração & dosagem , Envelhecimento Eritrocítico/efeitos dos fármacos , Eritropoese/efeitos dos fármacos , Macrófagos/fisiologia , Animais , Apoptose , Células da Medula Óssea/citologia , Ácido Clodrônico/toxicidade , Contagem de Eritrócitos , Índices de Eritrócitos , Células Precursoras Eritroides/citologia , Lipossomos , Ativação de Macrófagos/fisiologia , Macrófagos/efeitos dos fármacos , Fagocitose/fisiologia , Ratos , Ratos Wistar , Baço/citologia
16.
J Nutr ; 134(12): 3319-26, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15570032

RESUMO

A well-planned vegetarian diet has been stated to be adequate during pregnancy. The aim of the present study was to compare serum vitamin B-12 and homocysteine concentrations in pregnant women (n = 109) consuming vegetarian and Western diets and to evaluate the adequacy of current dietary reference intakes of vitamin B-12 for these women. Pregnant women adhering to vegetarian diets for at least 3 y, with subgroups of ovo-lacto vegetarians (OLVs; n = 27), low-meat eaters (LME, n = 43), and women eating an average Western diet (control group, n = 39), were recruited. Dietary vitamin B-12 intake, serum vitamin B-12, and plasma total homocysteine (tHcy) concentrations were measured in wk 9-12, 20-22, and 36-38 of pregnancy. During pregnancy serum vitamin B-12 concentrations of ovo-lacto vegetarians (P < 0.001) and low-meat eaters (P = 0.050) were lower than those of the control group. We observed the combination of low serum vitamin B-12 concentrations and elevated plasma tHcy in 22% of ovo-lacto vegetarians, in 10% of low-meat eaters, and in 3% of controls (P = 0.003). In OLVs, serum vitamin B-12 predicted 60% of the plasma tHcy variation (P < 0.001), but in LMEs and controls only <10% (NS). Serum vitamin B-12 concentrations increased and plasma tHcy decreased sharply with increasing dietary intake of vitamin B-12 toward a cutoff point of 3 mug/d. Pregnant women consuming a long-term predominantly vegetarian diet have an increased risk of vitamin B-12 deficiency. Current recommended dietary intakes urgently need reevaluation.


Assuntos
Dieta Vegetariana/efeitos adversos , Complicações na Gravidez/sangue , Gravidez/sangue , Deficiência de Vitamina B 12/sangue , Vitamina B 12/sangue , Adulto , Animais , Ovos , Feminino , Humanos , Leite
17.
J Pediatr Hematol Oncol ; 24(6): 503-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12218603

RESUMO

The authors attempted to assess the utility of interferon alpha2b treatment in a Polynesian girl with a relatively severe form of congenital dyserythropoietic anemia, type 1. The diagnosis was established using routine hematologic and biochemical tests, light and electron microscopy, and electrophoresis of red cell membrane proteins. Response to the treatment was monitored using the blood count and reticulocyte count. The patient was age 14 when interferon treatment was started. Previously, she had been partially dependent on transfusions, and gallstones and iron overload had developed. The dose of interferon alpha2b was initially 3 x 10 units three times a week for 1 year and 3 x 10 units twice a week thereafter. On this treatment, hemoglobin and reticulocytes increased and transfusions became unnecessary. In keeping with a few previous reports, interferon alpha2b proved to be effective in congenital dyserythropoietic anemia, type 1. The patient became transfusion-independent. More cases need to be studied to optimize the dosage of interferon alpha2b and determine how long the treatment can be tolerated.


Assuntos
Anemia Diseritropoética Congênita/tratamento farmacológico , Interferon-alfa/uso terapêutico , Anemia Diseritropoética Congênita/etnologia , Anemia Diseritropoética Congênita/patologia , Transfusão de Sangue , Eritroblastos/ultraestrutura , Feminino , Hemoglobinas/análise , Humanos , Lactente , Recém-Nascido , Interferon alfa-2 , Masculino , Linhagem , Polinésia/epidemiologia , Proteínas Recombinantes , Contagem de Reticulócitos
18.
Clin Chem ; 48(6 Pt 1): 928-33, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12029010

RESUMO

BACKGROUND: Because reference values for vitamin B(12) concentrations and vitamin B(12)-binding capacities for pregnant women have not been established, the reference values for nonpregnant women are often applied to assess vitamin B(12) status. The aim of the present study was to describe ranges of biochemical indices of vitamin B(12) status, including red blood cell (RBC) vitamin B(12), saturated and unsaturated cobalamin-binding proteins, and binding capacities in all trimesters of uncomplicated pregnancy. METHODS: A total of 39 healthy pregnant women with long-term daily intake of vitamin B(12) >2.6 microg/day and uncomplicated pregnancies participated in the study throughout their pregnancies. RBCs and serum vitamin B(12), holo-haptocorrin, unsaturated cobalamin-binding proteins, unsaturated and total vitamin B(12)-binding capacities, total homocysteine (tHcy), and RBC count were assessed in weeks 9-12, 20-22, and 36-38 of gestation. RESULTS: Significant changes in vitamin B(12) status occurred in the course of pregnancy. Serum vitamin B(12) concentrations and percentage of saturation of vitamin B(12)-binding proteins decreased steadily throughout pregnancy. In the third trimester, 35% of the participants had serum vitamin B(12) concentrations <150 pmol/L and 68.6% had <15% saturation of total vitamin B(12)-binding capacities, but no women had RBC vitamin B(12) concentrations <148 pmol/L. However, the decrease in these indices was not associated with reduced hemoglobin concentrations or RBC count or with increased tHcy concentrations. CONCLUSIONS: Our findings suggest that the reference values for vitamin B(12) status in nonpregnant women may not be applicable to pregnant women.


Assuntos
Gravidez/metabolismo , Transcobalaminas/metabolismo , Vitamina B 12/metabolismo , Dieta , Eritrócitos/metabolismo , Feminino , Humanos , Estudos Prospectivos , Valores de Referência , Vitamina B 12/administração & dosagem
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