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1.
J Fish Biol ; 103(3): 741-746, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37088723

RESUMO

Examination of the holotype of Synodontis nigrita, the type specimens of both its (potential) junior synonyms, Synodontis fascipinna and Synodontis ornatus, and an additional 306 specimens, previously identified as S. nigrita, confirmed that the interorbital width is the most important diagnostic character to distinguish S. nigrita from its Nilo-Sudanic (N-S), and Upper and Lower Guinea ichthyofaunal province congeners. Results revealed that this species has a typical N-S distribution. In addition, the occurrence of Synodontis violaceus in the Cross River is not corroborated. Therefore, it should be considered a typical West African species.


Assuntos
Peixes-Gato , Animais , Sudão , Guiné , Rios
2.
Parasit Vectors ; 16(1): 48, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732829

RESUMO

BACKGROUND: Monogenean parasites have never been formally reported on fishes from the Lufira River Basin. In this context, we decided to record the monogenean parasite fauna of three cichlid species found in the Upper Lufira River Basin for the first time by inventorizing their diversity (species composition) and analysing their infection parameters (prevalence, mean intensity and abundance). METHODS: The African cichlid fishes Oreochromis mweruensis, Coptodon rendalli and Serranochromis macrocephalus were selected for the study, given their economic value and their abundance in the Upper Lufira River Basin. Monogeneans were isolated from the gills and stomach, mounted on glass slides with either Hoyer's medium or ammonium picrate-glycerin for identification under a stereomicroscope, based on morphological analysis of genital and haptoral hard parts. Indices of diversity and infections parameters were calculated. RESULTS: A total of 13 gill monogenean parasite species (Cichlidogyrus dossoui, C. halli, C. karibae, C. mbirizei, C. papernastrema, C. quaestio, C. sclerosus, C. tiberianus, C. tilapiae, C. zambezensis, Scutogyrus gravivaginus, S. cf. bailloni and Gyrodactylus nyanzae) and one stomach monogenean (Enterogyrus malmbergi) were identified. A species richness (S) of 10 for O. mweruensis, S = 6 for C. rendalli and S = 2 for S. macrocephalus was recorded. Five parasite species were reported to be common amongst O. mweruensis and C. rendalli. According to cichlid species, the most prevalent parasite species was C. halli (prevalence [P] = 80.9%) on O. mweruensis, C. dossoui (P = 92.9%) on C. rendalli and C. karibae and C. zambezensis (both P = 9.1%) on S. macrocephalus. The parasite species with the highest mean intensity (MI) were G. nyanzae (MI = 8.7) on O. mweruensis, C. papernastrema (MI = 17.1) on C. rendalli and C. karibae (MI = 15) on S. macrocephalus. The findings indicate new host ranges for five parasites species (C. quaestio, S. cf. bailloni, E. malmbergi on O. mweruensis, C. halli on C. rendalli and C. karibae on S. macrocephalus) as well as new geographical records for all of them as they are recorded for the first time in the Lufira River Basin. CONCLUSIONS: This study highlighted the richness of monogenean communities in the Upper Lufira River Basin and is a starting point for future helminthological studies, such as on the use of fish parasites as indicators of anthropogenic impacts.


Assuntos
Ciclídeos , Doenças dos Peixes , Parasitos , Trematódeos , Animais , Ciclídeos/parasitologia , Rios , República Democrática do Congo , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Brânquias/parasitologia
3.
Proc Natl Acad Sci U S A ; 119(32): e2205797119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914171

RESUMO

Narcolepsy type 1 (NT1), a disorder caused by hypocretin/orexin (HCRT) cell loss, is associated with human leukocyte antigen (HLA)-DQ0602 (98%) and T cell receptor (TCR) polymorphisms. Increased CD4+ T cell reactivity to HCRT, especially DQ0602-presented amidated C-terminal HCRT (HCRTNH2), has been reported, and homology with pHA273-287 flu antigens from pandemic 2009 H1N1, an established trigger of the disease, suggests molecular mimicry. In this work, we extended DQ0602 tetramer and dextramer data to 77 cases and 44 controls, replicating our prior finding and testing 709 TCRs in Jurkat 76 T cells for functional activation. We found that fewer TCRs isolated with HCRTNH2 (∼11%) versus pHA273-287 or NP17-31 antigens (∼50%) were activated by their ligand. Single-cell characterization did not reveal phenotype differences in influenza versus HCRTNH2-reactive T cells, and analysis of TCR CDR3αß sequences showed TCR clustering by responses to antigens but no cross-peptide class reactivity. Our results do not support the existence of molecular mimicry between HCRT and pHA273-287 or NP17-31.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Narcolepsia , Orexinas , Receptores de Antígenos de Linfócitos T , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana , Narcolepsia/imunologia , Narcolepsia/fisiopatologia , Orexinas/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Virais/imunologia
4.
Sci Rep ; 11(1): 7841, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837283

RESUMO

Type 1 narcolepsy is strongly (98%) associated with human leukocyte antigen (HLA) class II DQA1*01:02/DQB1*06:02 (DQ0602) and highly associated with T cell receptor (TCR) alpha locus polymorphism as well as other immune regulatory loci. Increased incidence of narcolepsy was detected following the 2009 H1N1 pandemic and linked to Pandemrix vaccination, strongly supporting that narcolepsy is an autoimmune disorder. Although recent results suggest CD4+ T cell reactivity to neuropeptide hypocretin/orexin and cross-reactive flu peptide is involved, identification of other autoantigens has remained elusive. Here we study whether autoimmunity directed against Regulatory Factor X4 (RFX4), a protein co-localized with hypocretin, is involved in some cases of narcolepsy. Studying human serum, we found that autoantibodies against RFX4 were rare. Using RFX4 peptides bound to DQ0602 tetramers, antigen RFX4-86, -95, and -60 specific human CD4+ T cells were detected in 4/10 patients and 2 unaffected siblings, but not in others. Following culture with each cognate peptide, enriched autoreactive TCRαß clones were isolated by single-cell sorting and TCR sequenced. Homologous clones bearing TRBV4-2 and recognizing RFX4-86 in patients and one twin control of patient were identified. These results suggest the involvement of RFX4 CD4+ T cell autoreactivity in some cases of narcolepsy, but also in healthy donors.


Assuntos
Doenças Autoimunes/imunologia , Autoimunidade , Linfócitos T CD4-Positivos/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Narcolepsia/imunologia , Fatores de Transcrição de Fator Regulador X/imunologia , Vacinação/métodos , Adolescente , Adulto , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/sangue , Autoantígenos/imunologia , Doenças Autoimunes/sangue , Estudos de Casos e Controles , Criança , Reações Cruzadas , Feminino , Células HEK293 , Humanos , Influenza Humana/virologia , Masculino , Narcolepsia/sangue , Orexinas/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Fatores de Transcrição de Fator Regulador X/genética , Transfecção , Adulto Jovem
5.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33737391

RESUMO

Kleine-Levin syndrome (KLS) is a rare disorder characterized by severe episodic hypersomnia, with cognitive impairment accompanied by apathy or disinhibition. Pathophysiology is unknown, although imaging studies indicate decreased activity in hypothalamic/thalamic areas during episodes. Familial occurrence is increased, and risk is associated with reports of a difficult birth. We conducted a worldwide case-control genome-wide association study in 673 KLS cases collected over 14 y, and ethnically matched 15,341 control individuals. We found a strong genome-wide significant association (rs71947865, Odds Ratio [OR] = 1.48, P = 8.6 × 10-9) within the 3'region of TRANK1 gene locus, previously associated with bipolar disorder and schizophrenia. Strikingly, KLS cases with rs71947865 variant had significantly increased reports of a difficult birth. As perinatal outcomes have dramatically improved over the last 40 y, we further stratified our sample by birth years and found that recent cases had a significantly reduced rs71947865 association. While the rs71947865 association did not replicate in the entire follow-up sample of 171 KLS cases, rs71947865 was significantly associated with KLS in the subset follow-up sample of 59 KLS cases who reported birth difficulties (OR = 1.54, P = 0.01). Genetic liability of KLS as explained by polygenic risk scores was increased (pseudo R2 = 0.15; P < 2.0 × 10-22 at P = 0.5 threshold) in the follow-up sample. Pathway analysis of genetic associations identified enrichment of circadian regulation pathway genes in KLS cases. Our results suggest links between KLS, circadian regulation, and bipolar disorder, and indicate that the TRANK1 polymorphisms in conjunction with reported birth difficulties may predispose to KLS.


Assuntos
Citocinas/genética , Suscetibilidade a Doenças , Variação Genética , Síndrome de Kleine-Levin/complicações , Síndrome de Kleine-Levin/genética , Complicações do Trabalho de Parto/epidemiologia , Complicações do Trabalho de Parto/etiologia , Transtorno Bipolar/etiologia , Distúrbios do Sono por Sonolência Excessiva/etiologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Síndrome de Kleine-Levin/epidemiologia , Masculino , Razão de Chances , Polimorfismo Genético , Gravidez , Medição de Risco , Fatores de Risco
6.
Proc Natl Acad Sci U S A ; 115(52): E12323-E12332, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30541895

RESUMO

Type 1 narcolepsy (T1N) is caused by hypocretin/orexin (HCRT) neuronal loss. Association with the HLA DQB1*06:02/DQA1*01:02 (98% vs. 25%) heterodimer (DQ0602), T cell receptors (TCR) and other immune loci suggest autoimmunity but autoantigens are unknown. Onset is seasonal and associated with influenza A, notably pandemic 2009 H1N1 (pH1N1) infection and vaccination (Pandemrix). Peptides derived from HCRT and influenza A, including pH1N1, were screened for DQ0602 binding and presence of cognate DQ0602 tetramer-peptide-specific CD4+ T cells tested in 35 T1N cases and 22 DQ0602 controls. Higher reactivity to influenza pHA273-287 (pH1N1 specific), PR8 (H1N1 pre-2009 and H2N2)-specific NP17-31 and C-amidated but not native version of HCRT54-66 and HCRT86-97 (HCRTNH2) were observed in T1N. Single-cell TCR sequencing revealed sharing of CDR3ß TRBV4-2-CASSQETQGRNYGYTF in HCRTNH2 and pHA273-287-tetramers, suggesting molecular mimicry. This public CDR3ß uses TRBV4-2, a segment modulated by T1N-associated SNP rs1008599, suggesting causality. TCR-α/ß CDR3 motifs of HCRT54-66-NH2 and HCRT86-97-NH2 tetramers were extensively shared: notably public CDR3α, TRAV2-CAVETDSWGKLQF-TRAJ24, that uses TRAJ24, a chain modulated by T1N-associated SNPs rs1154155 and rs1483979. TCR-α/ß CDR3 sequences found in pHA273-287, NP17-31, and HCRTNH2 tetramer-positive CD4+ cells were also retrieved in single INF-γ-secreting CD4+ sorted cells stimulated with Pandemrix, independently confirming these results. Our results provide evidence for autoimmunity and molecular mimicry with flu antigens modulated by genetic components in the pathophysiology of T1N.


Assuntos
Narcolepsia/imunologia , Orexinas/imunologia , Orexinas/metabolismo , Adolescente , Adulto , Autoantígenos/metabolismo , Autoimunidade/imunologia , Linfócitos T CD4-Positivos/imunologia , Criança , Epitopos/imunologia , Feminino , Cadeias beta de HLA-DQ , Hemaglutininas , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Influenza Humana/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Mimetismo Molecular/imunologia , Orexinas/genética , Peptídeos/genética , Receptores de Antígenos de Linfócitos T/genética , Vacinação
7.
PLoS One ; 12(12): e0187305, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29220370

RESUMO

BACKGROUND: A recent publication suggested molecular mimicry of a nucleoprotein (NP) sequence from A/Puerto Rico/8/1934 (PR8) strain, the backbone used in the construction of the reassortant strain X-179A that was used in Pandemrix® vaccine, and reported on anti-hypocretin (HCRT) receptor 2 (anti-HCRTR2) autoantibodies in narcolepsy, mostly in post Pandemrix® narcolepsy cases (17 of 20 sera). In this study, we re-examined this hypothesis through mass spectrometry (MS) characterization of Pandemrix®, and two other pandemic H1N1 (pH1N1)-2009 vaccines, Arepanrix® and Focetria®, and analyzed anti-HCRTR2 autoantibodies in narcolepsy patients and controls using three independent strategies. METHODS: MS characterization of Pandemrix® (2 batches), Arepanrix® (4 batches) and Focetria® (1 batch) was conducted with mapping of NP 116I or 116M spectrogram. Two sets of narcolepsy cases and controls were used: 40 post Pandemrix® narcolepsy (PP-N) cases and 18 age-matched post Pandemrix® controls (PP-C), and 48 recent (≤6 months) early onset narcolepsy (EO-N) cases and 70 age-matched other controls (O-C). Anti-HCRTR2 autoantibodies were detected using three strategies: (1) Human embryonic kidney (HEK) 293T cells with transient expression of HCRTR2 were stained with human sera and then analyzed by flow cytometer; (2) In vitro translation of [35S]-radiolabelled HCRTR2 was incubated with human sera and immune complexes of autoantibody and [35S]-radiolabelled HCRTR2 were quantified using a radioligand-binding assay; (3) Optical density (OD) at 450 nm (OD450) of human serum immunoglobulin G (IgG) binding to HCRTR2 stably expressed in Chinese hamster ovary (CHO)-K1 cell line was measured using an in-cell enzyme-linked immunosorbent assay (ELISA). RESULTS: NP 116M mutations were predominantly present in all batches of Pandemrix®, Arepanrix® and Focetria®. The wild-type NP109-123 (ILYDKEEIRRIWRQA), a mimic to HCRTR234-45 (YDDEEFLRYLWR), was not found to bind to DQ0602. Three or four subjects were found positive for anti-HCRTR2 autoantibodies using two strategies or the third one, respectively. None of the post Pandemrix® narcolepsy cases (0 of 40 sera) was found positive with all three strategies. CONCLUSION: Anti-HCRTR2 autoantibody is not a significant biological feature of narcolepsy or of post Pandemrix® autoimmune responses.


Assuntos
Autoanticorpos/sangue , Narcolepsia/sangue , Receptores de Orexina/imunologia , Adolescente , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Células HEK293 , Humanos , Masculino , Espectrometria de Massas
8.
Transfusion ; 56(12): 3101-3111, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27696441

RESUMO

BACKGROUND: The aim of this study was to assess the cost effectiveness of introducing individual-donation nucleic acid testing (ID-NAT), in addition to serologic tests, compared with the exclusive use of serologic tests for the identification of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) I and II among blood donors in Zimbabwe. STUDY DESIGN AND METHODS: The costs, health consequences, and cost effectiveness of adding ID-NAT to serologic tests, compared with serologic testing alone, were estimated from a health care perspective using a decision-analytic model. RESULTS: The introduction of ID-NAT in addition to serologic tests would lower the risk of HBV, HCV, and HIV transmission to 46.9, 0.3, and 2.7 per 100,000 donations, respectively. ID-NAT would prevent an estimated 25, 6, and 9 HBV, HCV, and HIV transfusion-transmitted infections per 100,000 donations, respectively. The introduction of this intervention would result in an estimated 212 quality-adjusted life-years (QALYs) gained. The incremental cost-effectiveness ratio is estimated at US$17,774/QALY, a value far more than three times the gross national income per capita for Zimbabwe. CONCLUSION: Although the introduction of NAT could further improve the safety of the blood supply, current evidence suggests that it cannot be considered cost effective. Reducing the test costs for NAT through efficient donor recruitment, negotiating the price of reagents, and the efficient use of technology will improve cost effectiveness.


Assuntos
Doadores de Sangue , Segurança do Sangue/economia , Análise Custo-Benefício , HIV/isolamento & purificação , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Programas de Rastreamento/economia , Segurança do Sangue/métodos , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Hepatite B/prevenção & controle , Hepatite B/transmissão , Hepatite C/prevenção & controle , Hepatite C/transmissão , Humanos , Programas de Rastreamento/métodos , Técnicas de Amplificação de Ácido Nucleico/economia , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Sorológicos/economia , Testes Sorológicos/métodos , Zimbábue
9.
Transfusion ; 56(6 Pt 2): 1520-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26801952

RESUMO

BACKGROUND: Various models for estimating the residual risk (RR) of transmission of infections by blood transfusion have been published mainly based on data from high-income countries. However, to obtain the data required for such an assessment remains challenging for most developing settings. The National Blood Service Zimbabwe (NBSZ) adapted a published incidence-window period (IWP) model, which has less demanding data requirements. In this study we assess the impact of various definitions of blood donor subpopulations and models on RR estimates. We compared the outcomes of two published models and an adapted NBSZ model. STUDY DESIGN AND METHODS: The Schreiber IWP model (Model 1), an amended version (Model 2), and an adapted NBSZ model (Model 3) were applied. Variably the three models include prevalence, incidence, preseroconversion intervals, mean lifetime risk, and person-years at risk. Annual mean RR estimates and 95% confidence intervals for each of the three models for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) were determined using NBSZ blood donor data from 2002 through 2011. RESULTS: The annual mean RR estimates for Models 1 through 3 were 1 in 6542, 5805, and 6418, respectively for HIV; 1 in 1978, 2027, and 1628 for HBV; and 1 in 9588, 15,126, and 7750, for HCV. CONCLUSIONS: The adapted NBSZ model provided comparable results to the published methods and these highlight the high occurrence of HBV in Zimbabwe. The adapted NBSZ model could be used as an alternative to estimate RRs when in settings where two repeat donations are not available.


Assuntos
Doadores de Sangue/provisão & distribuição , Modelos Teóricos , Reação Transfusional , Viroses/transmissão , Adolescente , Feminino , Infecções por HIV/transmissão , Infecções por HIV/virologia , Hepatite B/transmissão , Hepatite B/virologia , Hepatite C/transmissão , Hepatite C/virologia , Humanos , Masculino , Medição de Risco , Viroses/virologia , Adulto Jovem , Zimbábue/epidemiologia
10.
Transfusion ; 56(3): 628-36, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26598799

RESUMO

BACKGROUND: There is lack of published data on the costs of blood and blood transfusion in sub-Saharan Africa. This study aimed to assess the unit costs of producing blood in Zimbabwe using an activity-based costing (ABC) method. STUDY DESIGN AND METHODS: A management accounting approach, based on the ABC method, was used to develop a cost model for blood. The production of blood was broken down into recruitment, collection, testing, processing, and storage plus distribution. Data for the year 2013 were collected retrospectively from budgets, financial and expenditure reports, databases, and interviews with transfusion personnel and managers. All direct and indirect costs, in 2013 US$, were allocated, accordingly, to the activities of blood acquisition. RESULTS: The total cost of producing safe blood in Zimbabwe for the year 2013 was US$8.6 million. Variable costs accounted for 51.2% of the total cost of production. The unit production costs for red blood cells (RBCs) were US$15.94 for recruitment, US$34.62 for collection, US$17.88 for testing, US$11.49 for processing, and US$3.06 for storage plus distribution. The overall cost of production of one unit of whole blood was US$118.42 and RBCs was US$130.94 constituting 12.4 and 13.7% of the country's annual GDP per capita. CONCLUSIONS: The high unit cost of producing blood relative to the annual GDP per capita demonstrates that acquiring safe blood is a burden on the health care sector in Zimbabwe. Introducing additional safety measures, such as nucleic acid amplification testing and pathogen reduction technology, although desirable, will further increase this burden.


Assuntos
Transfusão de Sangue/economia , Humanos , Zimbábue
11.
Blood Transfus ; 13(4): 600-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26192782

RESUMO

BACKGROUND: There are limited published data on the characteristics of blood transfusion recipients in sub-Saharan Africa. This study describes the demographic characteristics of blood transfusion recipients and patterns of blood and blood component use in Zimbabwe. MATERIALS AND METHODS: Data on the characteristics of the blood transfusion recipients (age, sex, blood group), blood components received (type, quantity), discharge diagnoses and outcomes following transfusion (discharge status, duration of stay in hospital), were retrospectively collected from four major hospitals for the period from January 1, 2012 to December 31, 2012. Diagnoses were grouped into broad categories according to the disease headings of the International Classification of Diseases (ICD-10). Surgical procedures were grouped into broad categories according to organ system using ICD-9. RESULTS: Most of the 1,793 transfusion recipients studied were female (63.2%) and in the reproductive age group, i.e. 15-49 years (65.3%). The median age of the recipients was 33 years (range, 0-93). The majority of these recipients (n=1,642; 91.6%) received a red blood cell transfusion. The majority of the patients were diagnosed with conditions related to pregnancy and childbirth (22.3%), and diseases of blood and blood-forming organs (17.7%). The median time spent in hospital was 8 days (range, 0-214) and in-hospital mortality was 15.4%. DISCUSSION: Our sample of blood transfusion recipients were fairly young and most of them received red blood cell transfusions. The majority of patients in the reproductive age group received blood transfusions for pregnancy and childbirth-related diagnoses.


Assuntos
Transfusão de Sangue , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Doenças Hematológicas/epidemiologia , Doenças Hematológicas/terapia , Mortalidade Hospitalar , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Classificação Internacional de Doenças , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Alta do Paciente/estatística & dados numéricos , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/terapia , Estudos Retrospectivos , Distribuição por Sexo , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Resultado do Tratamento , Adulto Jovem , Zimbábue/epidemiologia
12.
Mol Cancer ; 14: 67, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25889182

RESUMO

BACKGROUND: Gα13 (GNA13) is the α subunit of a heterotrimeric G protein that mediates signaling through specific G protein-coupled receptors (GPCRs). Our recent study showed that control of GNA13 expression by specific microRNAs (miRNAs or miRs) is important for prostate cancer cell invasion. However, little is known about the control of GNA13 expression in breast cancers. This project was carried out to determine (i) whether enhanced GNA13 expression is important for breast cancer cell invasion, and (ii) if so, the mechanism of deregulation of GNA13 expression in breast cancers. METHODS: To determine the probable miRNAs regulating GNA13, online miRNA target prediction tool Targetscan and Luciferase assays with GNA13-3'-UTR were used. Effect of miRNAs on GNA13 mRNA, protein and invasion was studied using RT-PCR, western blotting and in vitro Boyden chamber assay respectively. Cell proliferation was done using MTT assays. RESULTS: Overexpression of GNA13 in MCF-10a cells induced invasion, whereas knockdown of GNA13 expression in MDA-MB-231 cells inhibited invasion. Expression analysis of miRNAs predicted to bind the 3'-UTR of GNA13 revealed that miR-31 exhibited an inverse correlation to GNA13 protein expression in breast cancer cells. Ectopic expression of miR-31 in MDA-MB-231 cells significantly reduced GNA13 mRNA and protein levels, as well as GNA13-3'-UTR-reporter activity. Conversely, blocking miR-31 activity in MCF-10a cells induced GNA13 mRNA, protein and 3'-UTR reporter activity. Further, expression of miR-31 significantly inhibited MDA-MB-231 cell invasion, and this effect was partly rescued by ectopic expression of GNA13 in these cells. Examination of 48 human breast cancer tissues revealed that GNA13 mRNA levels were inversely correlated to miR-31 levels. CONCLUSIONS: These data provide strong evidence that GNA13 expression in breast cancer cells is regulated by post-transcriptional mechanisms involving miR-31. Additionally our data shows that miR-31 regulates breast cancer cell invasion partially via targeting GNA13 expression in breast cancer cells. Loss of miR-31 expression and increased GNA13 expression could be used as biomarkers of breast cancer progression.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , Regiões 3' não Traduzidas/genética , Fator 6 Ativador da Transcrição , Biomarcadores Tumorais/genética , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Invasividade Neoplásica/patologia , Processamento Pós-Transcricional do RNA/genética , RNA Mensageiro/genética
14.
Acta Crystallogr D Biol Crystallogr ; 69(Pt 10): 2017-26, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24100320

RESUMO

The first crystal structure of a barwin-like protein, named carwin, has been determined at high resolution by single-wavelength anomalous diffraction (SAD) phasing using the six intrinsic S atoms present in the protein. The barwin-like protein was purified from Carica papaya latex and crystallized in the orthorhombic space group P212121. Using in-house Cu Kα X-ray radiation, 16 cumulative diffraction data sets were acquired to increase the signal-to-noise level and thereby the anomalous scattering signal. A sequence-database search on the papaya genome identified two carwin isoforms of 122 residues in length, both containing six S atoms that yield an estimated Bijvoet ratio of 0.93% at 1.54 Šwavelength. A systematic analysis of data quality and redundancy was performed to assess the capacity to locate the S atoms and to phase the data. It was observed that the crystal decay was low during data collection and that successful S-SAD phasing could be obtained with a relatively low data multiplicity of about 7. Using a synchrotron source, high-resolution data (1 Å) were collected from two different crystal forms of the papaya latex carwin. The refined structures showed a central ß-barrel of six strands surrounded by several α-helices and loops. The ß-barrel of carwin appears to be a common structural module that is shared within several other unrelated proteins. Finally, the possible biological function of the protein is discussed.


Assuntos
Carica/química , Proteínas de Plantas/química , Enxofre/química , Difração de Raios X/métodos , Sequência de Aminoácidos , Carica/genética , Cristalização/métodos , Cristalografia por Raios X , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Estrutura Secundária de Proteína , Espalhamento de Radiação , Alinhamento de Sequência , Xamoterol/química
15.
Chem Biodivers ; 10(2): 224-32, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23418169

RESUMO

A chemical investigation of the Glyphaea brevis leaves and of the Monodora myristica fruits led to the identification of thirteen compounds, seven linear long-chain aliphatic compounds, 1, 2, 4, 6, and 9-11, three steroids, 3a, 3b, and 7, two triterpenes, 5a and 5b, and one polyol, 8. The compounds 2 and 8, previously mentioned in the literature, are here characterized by their complete (1)H- and (13)C-NMR assignments. This is the first report of a full NMR assignment for linear fatty acid esters of aliphatic primary alcohols and for meso-erythritol. Compound 5b and 8 were isolated for the first time from plant extracts of the Tiliaceae family, and compounds 9-11 from the Annonaceae plant family. Our results constitute the basis for further chemotaxonomic studies on the two species.


Assuntos
Annonaceae/química , Ácidos Graxos/análise , Malvaceae/química , Esteroides/análise , Triterpenos/análise , Annonaceae/classificação , Frutas/química , Espectroscopia de Ressonância Magnética , Malvaceae/classificação , Folhas de Planta/química
16.
J Biol Chem ; 288(11): 7986-7995, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23329838

RESUMO

G protein-coupled receptors (GPCRs) and their ligands have been implicated in progression and metastasis of several cancers. GPCRs signal through heterotrimeric G proteins, and among the different types of G proteins, GNA12/13 have been most closely linked to tumor progression. In this study, we explored the role of GNA13 in prostate cancer cell invasion and the mechanism of up-regulation of GNA13 in these cells. An initial screen for GNA13 protein expression showed that GNA13 is highly expressed in the most aggressive cancer cell lines. Knockdown of GNA13 in highly invasive PC3 cells revealed that these cells depend on GNA13 expression for their invasion, migration, and Rho activation. As mRNA levels in these cells did not correlate with protein levels, we assessed the potential involvement of micro-RNAs (miRNAs) in post-transcriptional control of GNA13 expression. Expression analysis of miRNAs predicted to bind the 3'-UTR of GNA13 revealed that miR-182 and miR-141/200a showed an inverse correlation to the protein expression in LnCAP and PC3 cells. Ectopic expression of miR-182 and miR-141/200a in PC3 cells significantly reduced protein levels, GNA13-3'-UTR reporter activity and in vitro invasion of these cells. This effect was blocked by restoration of GNA13 expression in these cells. Importantly, inhibition of miR-182 and miR-141/200a in LnCAP cells using specific miRNA inhibitors elevated the expression of GNA13 and enhanced invasion of these cells. These data provide strong evidence that GNA13 is an important mediator of prostate cancer cell invasion, and that miR-182 and miR-200 family members regulate its expression post-transcriptionally.


Assuntos
Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Quimiocina CXCL12/metabolismo , Colágeno/química , Combinação de Medicamentos , Células HEK293 , Humanos , Laminina/química , Ligantes , Masculino , Mutagênese Sítio-Dirigida , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Proteoglicanas/química , Processamento Pós-Transcricional do RNA
17.
Phytochemistry ; 83: 95-103, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22963707

RESUMO

Three compounds, ficusamide (1), ficusoside (2) and elasticoside (3), were isolated from the bark of aerial roots of Ficus elastica (Moraceae), together with nine known compounds, including four triterpenes, three steroids and two aliphatic linear alcohols. The chemical structures of the three compounds were established by extensive 1D and 2D NMR spectroscopy, mass spectrometry and by comparison with published data. The growth inhibitory effect of the crude extract and isolated compounds was evaluated against several microorganisms and fungi. The cytotoxicity against human cancer cell lines was also assessed. Ficusamide (1) displayed a moderate in vitro growth inhibitory activity against the human A549 lung cancer cell line and a strong activity against Staphylococcus saprophyticus, while elasticoside (3) showed a potent activity on Enterococcus faecalis.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Moraceae/química , Saponinas/farmacologia , Staphylococcus saprophyticus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Conformação Molecular , Componentes Aéreos da Planta/química , Raízes de Plantas/química , Saponinas/química , Saponinas/isolamento & purificação , Relação Estrutura-Atividade
18.
Int J Qual Health Care ; 24(6): 626-33, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22833617

RESUMO

QUALITY PROBLEM OR ISSUE: Patient identification in a teaching hospital in Malawi. Initial assessment 34% of hospital staff recalled a misidentification event in the preceding year; less than 10% of staff described the use of unique patient identifiers other than name when taking blood samples and 98% of laboratory requests included no identifiers other than name. CHOICE OF SOLUTION: Hospital identification guidelines based on WHO guidelines to introduce identification wristbands; encourage routine use of an identifier in addition to name on laboratory requests and improve bedside identification procedures. IMPLEMENTATION: Provision of wristbands, educational materials, workshops and distribution of written materials to promote the new guidelines with regular monitoring. EVALUATION: At 5 months 65% of in-patients wore wristbands compliant with WHO identification guidelines and 55% of cross-match forms used a second identifier. Only 10% of non-cross-match forms had a second identifier. The use of recommended bedside identification procedures was rarely observed. Guidelines were welcomed by both staff and patients; identification wristbands were found useful in difficult identification situations. Lack of time, staffing and unimportance of procedures were given as reasons for not following guidelines. LESSONS LEARNED: Identification procedures can be rapidly introduced in a developing world context in a manner acceptable to patients and staff. Tangible tools such as wristbands appeared easier to implement than changing practice by education. Recommendations for wider implementation include increased engagement of patients in addition to healthcare and management staff; use of rejection criteria for inadequately labeled samples; generating further evidence about the prevalence, type and consequences of patient misidentification events.


Assuntos
Administração Hospitalar/métodos , Sistemas de Identificação de Pacientes/métodos , Guias de Prática Clínica como Assunto , Qualidade da Assistência à Saúde/organização & administração , Fidelidade a Diretrizes , Humanos , Capacitação em Serviço , Malaui
19.
J Ethnopharmacol ; 128(2): 476-81, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20093175

RESUMO

AIM OF THE STUDY: Seven extracts and eight compounds from four selected Cameroonian medicinal plants, Solanecio mannii Hook f. (Asteraceae), Monodora myristica Dunal (Annonaceae), Albizia gummifera (J.F. Gmel) C.A. Smith (Fabaceae/Mimosoideae) and Glyphaea brevis (Spreng) Monachino (Tiliaceae), traditionally used for the treatment of hepatitis, parasites and other infectious diseases, were tested in vitro for their antimicrobial activity against Gram-positive (5 species) and Gram-negative (4 species) bacteria species and pathogenic yeasts (2 Candida species), to establish whether or not they have antimicrobial activity and to validate scientifically their use in traditional medicine. MATERIALS AND METHODS: The agar disc diffusion and the microbroth dilution methods were used to determine the zone of inhibition between the edge of the filter paper and the edge of the inhibition area (IZ) and the minimal inhibitory concentration (MIC) respectively. RESULTS: The most active extracts against Candida albicans and Candida krusei were respectively the cyclohexane extract from the fruits of Monodora myristica and the ethyl acetate extract from the stem bark of Albizia gummifera (MIC=6.3 microg/ml for both extracts). The lowest MIC value (1.6 microg/ml) for purified compounds was obtained on Candida albicans with a mixture of linear aliphatic primary alcohols (n-C24H50O to n-C30H62O), with n-hexacosanol (1b) as major compound and mixture of fatty acid esters of diunsaturated linear 1,2-diols (6). CONCLUSION: These results afford ground informations for the potential use of the crude extracts of these species as well as of some of the isolated compounds in bacterial and fungal infections.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Micoses/tratamento farmacológico , Plantas Medicinais/química , Leveduras/efeitos dos fármacos , Albizzia , Annonaceae , Anti-Infecciosos/isolamento & purificação , Camarões , Candida/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Formas de Dosagem , Álcoois Graxos/química , Medicina Tradicional , Testes de Sensibilidade Microbiana/métodos , Tiliaceae
20.
Biologicals ; 38(1): 78-80, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20079663

RESUMO

Blood Transfusion Safety is dependent on effectively organised and managed blood services, which have adequate financial resources, skilled manpower, appropriate infrastructure and quality management systems in place. 80% of the world's population has access to 20% of the supply blood products, of which little is consistently safe. HIV highlighted the importance of blood safety. The lack of effective blood services in low human development index (LHDI), developing countries, has lead to international funding and capacity building for more than three decades. The initial strategies focused on providing HIV testing reagents to prevention transmission, however this only addresses one part of blood safety. Blood safety is not only dependent on preventing HIV transmission. In many populations there are other infectious agents, which have a higher prevalence. Ensuring the correct blood is provided to the patient depends on: well managed services with effective leadership and adequate budgets; capacity building and retention of skilled experienced staff; availability of laboratory equipment, correctly maintained; blood cold chain systems; procedures for tendering, purchasing and ensuring an unbroken supply of reagents and consumables; and quality management systems. Barriers for simplified effective tendering, procurement and contracting require urgent attention and coordination of all funding organisations to ensure an unbroken supply of reagents.


Assuntos
Armazenamento de Sangue/métodos , Bancos de Sangue/economia , Transfusão de Sangue/normas , Qualidade de Produtos para o Consumidor/normas , Manutenção/economia , Bancos de Sangue/legislação & jurisprudência , Bancos de Sangue/organização & administração , Transfusão de Sangue/instrumentação , Transfusão de Sangue/legislação & jurisprudência , Transfusão de Sangue/métodos , Qualidade de Produtos para o Consumidor/legislação & jurisprudência , Países em Desenvolvimento/economia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Manutenção/legislação & jurisprudência , Manutenção/métodos , Garantia da Qualidade dos Cuidados de Saúde/legislação & jurisprudência , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Gestão da Segurança/economia , Gestão da Segurança/legislação & jurisprudência , Gestão da Segurança/normas
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