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1.
Pediatr Blood Cancer ; 70(1): e30067, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36250986

RESUMO

Unstable gamma globin variants can cause transient neonatal hemolytic anemia. We have identified a novel variant in a newborn who presented with jaundice and anemia requiring phototherapy and red blood cell transfusion. The patient was found to be heterozygous for the mutation HGB2:c.290T>C, p.Leu97Pro, which we have termed hemoglobin (Hb) Wareham. This substitution is expected to generate an unstable hemoglobin with increased oxygen affinity based on the homologous mutation previously described in the beta globin gene, which is termed as Hb Debrousse. The patient fully recovered by 9 months of age as expected with the transition from fetal to adult hemoglobin.


Assuntos
Anemia Hemolítica , Hemoglobinas Anormais , gama-Globinas , Humanos , Recém-Nascido , Anemia Hemolítica/genética , Globinas beta/genética , gama-Globinas/genética , Hemoglobinas Anormais/genética , Heterozigoto , Mutação , Lactente
2.
Environ Sci Pollut Res Int ; 29(46): 69472-69490, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35567684

RESUMO

Accurate estimations of municipal solid waste (MSW) generation are vital to effective MSW management systems. While various single-point estimation approaches have been developed, the non-linearity and multiple site-specific influencing factors associated with MSW management systems make it challenging to forecast MSW generation quantities precisely. To address these concerns, this study developed a two-stage modeling and scenario analysis procedure for MSW generation and taking Shanghai as a test case demonstrated its viability. In the first stage, nine influencing factors were selected, and a hybrid novel forecasting model based on a long short-term memory neural network and an improved particle swarm optimization (IPSO-LSTM) was proposed for the forecasting of the MSW generation quantities, after which actual Shanghai data from 1980 to 2019 were used to test the performance. In the second stage, the future influencing variable values in different scenarios were predicted using an improved grey model, after which the predicted Shanghai MSW generation quantities from 2025 to 2035 were evaluated under various scenarios. It was found that (1) the proposed IPSO-LSTM had higher accuracy than the benchmark models; (2) the MSW generation quantities are expected to respectively increase to 9.971, 9.684, and 9.090 million tons by 2025 and 11.402, 11.285, and 10.240 by 2035 under the low, benchmark, and high scenarios; and (3) the MSW generation differences between the high and medium scenarios were decreasing.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , China , Cidades , Memória de Curto Prazo , Redes Neurais de Computação , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Gerenciamento de Resíduos/métodos
4.
Molecules ; 26(23)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34885762

RESUMO

The long-acting parenteral formulation of the HIV integrase inhibitor cabotegravir (GSK744) is currently being developed to prevent HIV infections, benefiting from infrequent dosing and high efficacy. The crystal structure can affect the bioavailability and efficacy of cabotegravir. However, the stability determination of crystal structures of GSK744 have remained a challenge. Here, we introduced an ab initio protocol to determine the stability of the crystal structures of pharmaceutical molecules, which were obtained from crystal structure prediction process starting from the molecular diagram. Using GSK744 as a case study, the ab initio predicted that Gibbs free energy provides reliable further refinement of the predicted crystal structures and presents its capability for becoming a crystal stability determination approach in the future. The proposed work can assist in the comprehensive screening of pharmaceutical design and can provide structural predictions and stability evaluation for pharmaceutical crystals.


Assuntos
Dicetopiperazinas/química , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/química , HIV-1/efeitos dos fármacos , Piridonas/química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/uso terapêutico , Cristalografia por Raios X , Dicetopiperazinas/uso terapêutico , Infecções por HIV/genética , Infecções por HIV/virologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , HIV-1/ultraestrutura , Humanos , Piridonas/uso terapêutico , Teoria Quântica
5.
Sci Rep ; 11(1): 7076, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782489

RESUMO

With the rapid growth of energy demand and the depletion of existing energy resources, the new materials with superior performances, low costs and environmental friendliness for energy production and storage are explored. Di-p-tolyl disulfide (p-Tol2S2) is a typical lubricating material, which has been applied in the field of energy storage. The conformational properties and phase transformations of p-Tol2S2 have been studied by pioneers, but their polymorphs and the polymorphism induced crystal structure changes require further analysis. In this study, we perform the crystal structural screening, prediction and optimization of p-Tol2S2 crystal with quantum mechanical calculations, i.e., density functional theory (DFT) and second-order Møller-Plesset perturbation (MP2) methods. A series of crystal structures with different molecular arrangements are generated based on the crystal structure screening. As compared to long-established lattice energy calculation, we take an advantage of using more accurate technique, which is Gibbs free energy calculation. It considers the effects of entropy and temperature to predict the crystal structures and energy landscape. By comparing the Gibbs free energies between predicted and experimental structures, we found that phase α is the most stable structure for p-Tol2S2 crystal at ambient temperature and standard atmospheric pressure. Furthermore, we provide an efficient method to discriminate different polymorphs that are otherwise difficult to be identified based on the Raman/IR spectra. The proposed work enable us to evaluate the quality of various crystal polymorphs rapidly.

7.
Se Pu ; 37(5): 547-550, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31070339

RESUMO

A method to determine fatty alkyl dimethyl tertiary amines by gas chromatography (GC) was set up using HP-INNOWax capillary column, hydrogen flame ionization detector (FID) and temperature programming. The linearities were all excellent in the range of 0.005-1.0 g/L with the correlation coefficients being above 0.9996. The limits of detection (LODs, S/N=3) of the method were between 0.001 g/L and 0.002 g/L, and the limits of quantification (LOQs, S/N=10) were between 0.003 g/L and 0.005 g/L. The recoveries ranged between 90% and 130% with relative standard deviations of 1.3%-6.9% (n=6). The proposed method has the advantages of wide linear range, higher recovery, and selectivity, which was suitable for the quantitative analysis of fatty alkyl dimethyl tertiary amines and monitoring process control in industrial production. The method was faster and more accurate than titration, and also precluded the need for pre-column derivatization and determination by liquid chromatography-tandem mass spectrometry.

8.
Blood ; 133(21): 2255-2262, 2019 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-30704988

RESUMO

The thalassemias are compelling targets for therapeutic genome editing in part because monoallelic correction of a subset of hematopoietic stem cells (HSCs) would be sufficient for enduring disease amelioration. A primary challenge is the development of efficient repair strategies that are effective in HSCs. Here, we demonstrate that allelic disruption of aberrant splice sites, one of the major classes of thalassemia mutations, is a robust approach to restore gene function. We target the IVS1-110G>A mutation using Cas9 ribonucleoprotein (RNP) and the IVS2-654C>T mutation by Cas12a/Cpf1 RNP in primary CD34+ hematopoietic stem and progenitor cells (HSPCs) from ß-thalassemia patients. Each of these nuclease complexes achieves high efficiency and penetrance of therapeutic edits. Erythroid progeny of edited patient HSPCs show reversal of aberrant splicing and restoration of ß-globin expression. This strategy could enable correction of a substantial fraction of transfusion-dependent ß-thalassemia genotypes with currently available gene-editing technology.


Assuntos
Edição de Genes , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas , Sítios de Splice de RNA , Splicing de RNA , Globinas beta , Talassemia beta , Sistemas CRISPR-Cas , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Mutação Puntual , Globinas beta/biossíntese , Globinas beta/genética , Talassemia beta/genética , Talassemia beta/metabolismo , Talassemia beta/terapia
9.
J Pediatr Hematol Oncol ; 40(3): e145-e147, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29309373

RESUMO

ß thalassemia is characterized by a deficient production of functional ß-globin chains and a relative excess of α-globin chains. An extremely diverse clinical spectrum-asymptomatic to transfusion-dependent-is primarily due to homozygosity or compound heterozygosity for the very large number of ß-thalassemia-causing mutations, along with interacting mutations that affect the α-globin and γ-globin genes and their expression. We report a case of a 16-month-old boy who was initially diagnosed with iron deficiency anemia until he was later found to be homozygous for a severe ß-thalassemia genotype with a mild hematologic phenotype. This was likely as a result of his ability to produce high levels of fetal hemoglobin.


Assuntos
Talassemia beta , Anemia/genética , Hemoglobina Fetal/biossíntese , Genótipo , Homozigoto , Humanos , Lactente , Masculino , Mutação , Fenótipo , Talassemia beta/complicações , Talassemia beta/genética
11.
Blood Cells Mol Dis ; 69: 1-9, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29227829

RESUMO

The HBS1L-MYB intergenic region (chr6q23) regulates erythroid cell proliferation, maturation, and fetal hemoglobin (HbF) expression. An enhancer element within this locus, highlighted by a 3-bp deletion polymorphism (rs66650371), is known to interact with the promoter of the neighboring gene, MYB, to increase its expression, thereby regulating HbF production. RNA polymerase II binding and a 50-bp transcript from this enhancer region reported in ENCODE datasets suggested the presence of a long noncoding RNA (lncRNA). We characterized a novel 1283bp transcript (HMI-LNCRNA; chr6:135,096,362-135,097,644; hg38) that was transcribed from the enhancer region of MYB. Within erythroid cells, HMI-LNCRNA was almost exclusively present in nucleus, and was much less abundant than the mRNA for MYB. HMI-LNCRNA expression was significantly higher in erythroblasts derived from cultured adult peripheral blood CD34+ cells which expressed more HBB, compared to erythroblasts from cultured cord blood CD34+ cells which expressed much more HBG. Down-regulation of HMI-LNCRNA in HUDEP-2 cells, which expressed mostly HBB, significantly upregulated HBG expression both at the mRNA (200-fold) and protein levels, and promoted erythroid maturation. No change was found in the expression of BCL11A and other key transcription factors known to modulate HBG expression. HMI-LNCRNA plays an important role in regulating HBG expression, and its downregulation can result in a significant increase in HbF. HMI-LNCRNA might be a potential therapeutic target for HbF induction treatment in sickle cell disease and ß-thalassemia.


Assuntos
Cromossomos Humanos Par 6 , DNA Intergênico/genética , Hemoglobina Fetal/genética , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica , Genes myb , RNA Longo não Codificante , Sequência de Bases , Diferenciação Celular , Linhagem Celular , Eritroblastos/metabolismo , Células Eritroides/metabolismo , Técnicas de Silenciamento de Genes , Células-Tronco Hematopoéticas/metabolismo , Humanos , Locos de Características Quantitativas
12.
Artigo em Inglês | MEDLINE | ID: mdl-28704955

RESUMO

Accurate PM2.5 concentration forecasting is crucial for protecting public health and atmospheric environment. However, the intermittent and unstable nature of PM2.5 concentration series makes its forecasting become a very difficult task. In order to improve the forecast accuracy of PM2.5 concentration, this paper proposes a hybrid model based on wavelet transform (WT), variational mode decomposition (VMD) and back propagation (BP) neural network optimized by differential evolution (DE) algorithm. Firstly, WT is employed to disassemble the PM2.5 concentration series into a number of subsets with different frequencies. Secondly, VMD is applied to decompose each subset into a set of variational modes (VMs). Thirdly, DE-BP model is utilized to forecast all the VMs. Fourthly, the forecast value of each subset is obtained through aggregating the forecast results of all the VMs obtained from VMD decomposition of this subset. Finally, the final forecast series of PM2.5 concentration is obtained by adding up the forecast values of all subsets. Two PM2.5 concentration series collected from Wuhan and Tianjin, respectively, located in China are used to test the effectiveness of the proposed model. The results demonstrate that the proposed model outperforms all the other considered models in this paper.


Assuntos
Poluentes Atmosféricos/análise , Modelos Teóricos , Material Particulado/análise , Algoritmos , China , Previsões , Humanos
13.
Hemoglobin ; 41(1): 50-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28395541

RESUMO

Hemoglobin (Hb) is the protein responsible for oxygen transportation. It is a tetrameric protein comprising two α- and two ß-globin subunits. In the literature, a large number of mutations in the α- and ß-globin genes have been documented. Among these mutations, Hb Presbyterian (HBB: c.327 C>G), is a naturally occurring mutant exerting low oxygen affinity. The C to G exchange (AAC>AAG) at codon 108 of the ß-globin gene results in the substitution of asparagine by lysine. Here, we document the identification of HBB: c.327 C>G in a 6-year-old female patient and her father from Nicaragua and Cuba, respectively. The presence of the abnormal Hb was confirmed by cellulose acetate electrophoresis, high performance liquid chromatography (HPLC) and genomic DNA sequencing. The ß-globin gene sequences for both, father and daughter, disclosed the heterozygous mutation at codon 108 to be Hb Presbyterian or HBB: c.327 C>G. The mutant Hb was previously reported in four families from North America, Germany, Japan and Spain, respectively. This is the fifth family carrying HBB: c.327 C>G described to date and the first report from Latin America.


Assuntos
Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Hemoglobinas Anormais/genética , Mutação , Globinas beta/genética , Adulto , Alelos , Criança , Códon , Análise Mutacional de DNA , Feminino , Genótipo , Hemoglobinopatias/sangue , Humanos , Masculino , Nicarágua , Fenótipo
14.
Stem Cell Reports ; 8(4): 1076-1085, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28111279

RESUMO

Sickle cell anemia affects millions of people worldwide and is an emerging global health burden. As part of a large NIH-funded NextGen Consortium, we generated a diverse, comprehensive, and fully characterized library of sickle-cell-disease-specific induced pluripotent stem cells (iPSCs) from patients of different ethnicities, ß-globin gene (HBB) haplotypes, and fetal hemoglobin (HbF) levels. iPSCs stand to revolutionize the way we study human development, model disease, and perhaps eventually, treat patients. Here, we describe this unique resource for the study of sickle cell disease, including novel haplotype-specific polymorphisms that affect disease severity, as well as for the development of patient-specific therapeutics for this phenotypically diverse disorder. As a complement to this library, and as proof of principle for future cell- and gene-based therapies, we also designed and employed CRISPR/Cas gene editing tools to correct the sickle hemoglobin (HbS) mutation.


Assuntos
Anemia Falciforme/genética , Anemia Falciforme/terapia , Sistemas CRISPR-Cas , Terapia Genética , Hemoglobina Falciforme/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Globinas beta/genética , Adolescente , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/etnologia , Sequência de Bases , Linhagem Celular , Células Cultivadas , Criança , Pré-Escolar , Células Eritroides/citologia , Células Eritroides/metabolismo , Feminino , Hemoglobina Fetal/análise , Terapia Genética/métodos , Haplótipos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Polimorfismo Genético , Transcriptoma , Adulto Jovem
15.
Sci Total Environ ; 580: 719-733, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27989476

RESUMO

The randomness, non-stationarity and irregularity of air quality index (AQI) series bring the difficulty of AQI forecasting. To enhance forecast accuracy, a novel hybrid forecasting model combining two-phase decomposition technique and extreme learning machine (ELM) optimized by differential evolution (DE) algorithm is developed for AQI forecasting in this paper. In phase I, the complementary ensemble empirical mode decomposition (CEEMD) is utilized to decompose the AQI series into a set of intrinsic mode functions (IMFs) with different frequencies; in phase II, in order to further handle the high frequency IMFs which will increase the forecast difficulty, variational mode decomposition (VMD) is employed to decompose the high frequency IMFs into a number of variational modes (VMs). Then, the ELM model optimized by DE algorithm is applied to forecast all the IMFs and VMs. Finally, the forecast value of each high frequency IMF is obtained through adding up the forecast results of all corresponding VMs, and the forecast series of AQI is obtained by aggregating the forecast results of all IMFs. To verify and validate the proposed model, two daily AQI series from July 1, 2014 to June 30, 2016 collected from Beijing and Shanghai located in China are taken as the test cases to conduct the empirical study. The experimental results show that the proposed hybrid model based on two-phase decomposition technique is remarkably superior to all other considered models for its higher forecast accuracy.

16.
Am J Hematol ; 91(11): 1118-1122, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27501013

RESUMO

Fetal hemoglobin (HbF) levels are higher in the Arab-Indian (AI) ß-globin gene haplotype of sickle cell anemia compared with African-origin haplotypes. To study genetic elements that effect HbF expression in the AI haplotype we completed whole genome sequencing in 14 Saudi AI haplotype sickle hemoglobin homozygotes-seven selected for low HbF (8.2% ± 1.3%) and seven selected for high HbF (23.5% ± 2.6%). An intronic single nucleotide polymorphism (SNP) in ANTXR1, an anthrax toxin receptor (chromosome 2p13), was associated with HbF. These results were replicated in two independent Saudi AI haplotype cohorts of 120 and 139 patients, but not in 76 Saudi Benin haplotype, 894 African origin haplotype and 44 AI haplotype patients of Indian origin, suggesting that this association is effective only in the Saudi AI haplotype background. ANTXR1 variants explained 10% of the HbF variability compared with 8% for BCL11A. These two genes had independent, additive effects on HbF and together explained about 15% of HbF variability in Saudi AI sickle cell anemia patients. ANTXR1 was expressed at mRNA and protein levels in erythroid progenitors derived from induced pluripotent stem cells (iPSCs) and CD34+ cells. As CD34+ cells matured and their HbF decreased ANTXR1 expression increased; as iPSCs differentiated and their HbF increased, ANTXR1 expression decreased. Along with elements in cis to the HbF genes, ANTXR1 contributes to the variation in HbF in Saudi AI haplotype sickle cell anemia and is the first gene in trans to HBB that is associated with HbF only in carriers of the Saudi AI haplotype. Am. J. Hematol. 91:1118-1122, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Anemia Falciforme/genética , Hemoglobina Fetal/genética , Haplótipos , Adolescente , Adulto , Árabes/genética , Proteínas de Transporte/genética , Criança , Pré-Escolar , Feminino , Expressão Gênica , Humanos , Masculino , Proteínas dos Microfilamentos , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/genética , Proteínas Repressoras , População Branca/genética , Adulto Jovem , Globinas beta/genética
18.
Ann N Y Acad Sci ; 1368(1): 49-55, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27123947

RESUMO

Most ß-thalassemia carriers have mild anemia, low mean corpuscular volume and mean corpuscular hemoglobin, and elevated hemoglobin α2 (HbA2 ). However, there is considerable variability resulting from coinheritance with α- and/or δ-globin gene mutations, dominant inheritance of ß-thalassemia mutations, highly unstable variant globin chains, large deletions removing part or all of the ß-globin gene cluster, loss of heterozygosity of the ß-globin gene cluster during development, or concomitant erythroid enzyme or membrane protein abnormalities. Recognition of the specific abnormality and correct diagnosis can allay anxiety and unnecessary investigation, help formulate treatment programs, and deliver appropriate genetic and family counseling.


Assuntos
Heterozigoto , Fenótipo , Talassemia beta/genética , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/genética , Animais , Hemoglobina A2/genética , Humanos , Talassemia beta/diagnóstico , Talassemia beta/epidemiologia
19.
Br J Haematol ; 172(6): 958-65, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26771086

RESUMO

Two 21-year old dizygotic twin men of Iraqi descent were homozygous for HBB codon 8, deletion of two nucleotides (-AA) frame-shift ß(0) -thalassaemia mutation (FSC8; HBB:c25_26delAA). Both were clinically well, had splenomegaly, and were never transfused. They had mild microcytic anaemia (Hb 120-130 g/l) and 98% of their haemoglobin was fetal haemoglobin (HbF). Both were carriers of Hph α-thalassaemia mutation. On the three major HbF quantitative trait loci (QTL), the twins were homozygous for G>A HBG2 Xmn1 site at single nucleotide polymorphism (SNP) rs7482144, homozygous for 3-bp deletion HBS1L-MYB intergenic polymorphism (HMIP) at rs66650371, and heterozygous for the A>C BCL11A intron 2 polymorphism at rs766432. These findings were compared with those found in 22 other FSC8 homozygote patients: four presented with thalassaemia intermedia phenotype, and 18 were transfusion dependent. The inheritance of homozygosity for HMIP 3-bp deletion at rs66650371 and heterozygosity for Hph α-thalassaemia mutation was found in the twins and not found in any of the other 22 patients. Further studies are needed to uncover likely additional genetic variants that could contribute to the exceptionally high HbF levels and mild phenotype in these twins.


Assuntos
Doenças em Gêmeos/genética , Mutação da Fase de Leitura , Talassemia beta/genética , Proteínas de Transporte/genética , Feminino , Hemoglobina Fetal/análise , Hemoglobina Fetal/genética , Genes myb , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Proteínas Repressoras , Gêmeos Dizigóticos/genética , Adulto Jovem
20.
Hemoglobin ; 40(1): 64-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26372199

RESUMO

Hereditary persistence of fetal hemoglobin (HPFH) can be caused by point mutations in the γ-globin gene promoters. We report three rare cases: a child compound heterozygous for Hb S (HBB: c.20A > T) and HPFH with a novel point mutation in the (A)γ-globin gene promoter who had 42.0% Hb S, 17.0% Hb A and 38.0% Hb F; a man with Hb SC (HBB: c.19G > A) disease and a point mutation in the (G)γ-globin gene promoter who had 54.0% Hb S, 18.0% Hb C and 25.0% Hb F; a child heterozygous for Hb S and HPFH due to mutations in both the (A)γ- and (G)γ-globin gene promoters in cis [(G)γ(A)γ(ß(+)) HPFH], with 67.0% Hb A, 6.5% Hb S and 25.0% Hb F.


Assuntos
Hemoglobina Fetal/genética , Doença da Hemoglobina SC/genética , Hemoglobina Falciforme/genética , Mutação Puntual , Traço Falciforme/genética , gama-Globinas/genética , Adulto , Feminino , Hemoglobina C/genética , Heterozigoto , Humanos , Lactente , Masculino , Regiões Promotoras Genéticas
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