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1.
Schuetz A Haule A Reither K Ngwenyama N Rachow A Meyerhans A Maboko L Koup RA Hoelscher M Geldmacher C 《PloS one》2011,6(11):e27284
The level of bacterial activity is only poorly defined during asymptomatic Mycobacterium tuberculosis (MTB) infection. The objective was to study the capacity of a new biomarker, the expression of the T cell maturation marker CD27 on MTB-specific CD4 T cells, to identify active tuberculosis (TB) disease in subjects from a MTB and HIV endemic region. The frequency and CD27 expression of circulating MTB-specific CD4 T cells was determined in 96 study participants after stimulation with purified protein derivative (PPD) using intracellular cytokine staining for IFNgamma (IFNγ). Subjects were then stratified by their TB and HIV status. Within PPD responders, a CD27− phenotype was associated with active TB in HIV− (p = 0.0003) and HIV+ (p = 0.057) subjects, respectively. In addition, loss of CD27 expression preceded development of active TB in one HIV seroconverter. Interestingly, in contrast to HIV− subjects, MTB-specific CD4 T cell populations from HIV+ TB-asymptomatic subjects were often dominated by CD27− cells. These data indicate that down-regulation of CD27 on MTB-specific CD4 T cell could be used as a biomarker of active TB, potentially preceding clinical TB disease. Furthermore, these data are consistent with the hypothesis that late, chronic HIV infection is frequently associated with increased mycobacterial activity in vivo. The analysis of T cell maturation and activation markers might thus be a useful tool to monitor TB disease progression. 相似文献
2.
João Paulo Rodrigues Martins Luiz Carlos de Almeida Rodrigues Lorenzo Toscano Conde Andreia Barcelos Passos Lima Gontijo Antelmo Ralph Falqueto 《Plant biosystems》2020,154(1):87-99
AbstractUnder in vitro culture conditions, plants may present physiological and anatomical disorders, which can interfere negatively after ex vitro transfer. The aim of this investigation was to analyze the impacts of natural ventilation and sucrose supply on the anatomy and physiology of Vriesea imperialis. Plants previously grown in vitro were transferred to culture medium containing 0, 15, 30 or 45?g L?1 sucrose. Three different culture container sealing systems were tested: lids with a green filter (81.35 gas exchanges per day), yellow filter (13.09 gas exchanges per day) or lids with a yellow filter covered with three layers of transparent polyvinylchloride (PVC) film (blocking fluent gas exchange). Sucrose concentrations influenced thickness, lignin and suberin deposition of exodermis cell wall. The modifications verified in leaves, such as higher density of stomata and trichome scales, showed that sucrose can induce osmotic stress in the plants. Photomixotrophic conditions, using containers with intermediate rate of gas exchange (yellow filter) and with 15–30?g L?1 sucrose, produced an improvement in the growth traits and did not induce anatomical and physiological disturbances. 相似文献
3.
Martins João Paulo Rodrigues Vasconcelos Leandro Lopes de Braga Priscila da Conceição de Souza Rossini Franciele Pereira Conde Lorenzo Toscano Rodrigues Luiz Carlos de Almeida Falqueto Antelmo Ralph Gontijo Andreia Barcelos Passos Lima 《Plant Cell, Tissue and Organ Culture》2020,143(2):303-318
Plant Cell, Tissue and Organ Culture (PCTOC) - Copper (Cu) is an essential metal and both its deficiency and excess has negative effects on the growth and physiology of plants. Some plant species... 相似文献
4.
Rossini Franciele Pereira Martins João Paulo Rodrigues Moreira Samuel Werner Conde Lorenzo Toscano Clairvil Evens Braga Priscila da Conceição de Souza Falqueto Antelmo Ralph Gontijo Andreia Barcelos Passos Lima 《Plant Cell, Tissue and Organ Culture》2022,150(1):223-236
Plant Cell, Tissue and Organ Culture (PCTOC) - Despite having the ability to bioaccumulate trace elements such as cadmium (Cd), many species also present morphophysiological disorders that can... 相似文献
5.
CD8 T-cell recognition of multiple epitopes within specific Gag regions is associated with maintenance of a low steady-state viremia in human immunodeficiency virus type 1-seropositive patients
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Geldmacher C Currier JR Herrmann E Haule A Kuta E McCutchan F Njovu L Geis S Hoffmann O Maboko L Williamson C Birx D Meyerhans A Cox J Hoelscher M 《Journal of virology》2007,81(5):2440-2448
The importance of HLA class I-restricted CD8 T-cell responses in the control of human immunodeficiency virus (HIV) infection is generally accepted. While several studies have shown an association of certain HLA class I alleles with slower disease progression, it is not fully established whether this effect is mediated by HIV-specific CD8 T-cell responses restricted by these alleles. In order to study the influence of the HLA class I alleles on the HIV-specific CD8 T-cell response and on viral control, we have assessed HIV-specific epitope recognition, plasma viral load, and expression of HLA class I alleles in a cohort of HIV-seropositive bar workers. Possession of the HLA class I alleles B5801, B8101, and B0702 was associated with a low median viral load and simultaneously with a broader median recognition of Gag epitopes compared to all other HLA alleles (twofold increase) (P = 0.0035). We further found an inverse linear relationship between the number of Gag epitopes recognized and the plasma viral load (R = -0.36; P = 0.0016). Particularly, recognition of multiple epitopes within two regions of Gag (amino acids [aa] 1 to 75 and aa 248 to 500) was associated with the maintenance of a low steady-state viremia, even years after acute infection. 相似文献
6.
Jonathan Mnkai Thomas F. Marandu Jacklina Mhidze Agatha Urio Lucas Maganga Antelmo Haule Godfrey Kavishe Elizabeth Ntapara Nhamo Chiwerengo Petra Clowes Sacha Horn Maureen Mosoba Wilfred Lazarus Abdallah Ngenya Akili Kalinga Alex Debrah Friedrich Rieß Elmar Saathoff Christof Geldmacher Achim Hoerauf Michael Hoelscher Mkunde Chachage Inge Kroidl 《PLoS neglected tropical diseases》2022,16(7)
BackgroundLymphatic filariasis is a mosquito transmitted parasitic infection in tropical regions. Annual mass treatment with ivermectin and albendazole is used for transmission control of Wuchereria bancrofti, the infective agent of lymphatic filariasis in many African countries, including Tanzania.MethodologyIn a general population study in Southwest Tanzania, individuals were tested for circulating filarial antigen, an indicator of W. bancrofti adult worm burden in 2009 before mass drug administration commenced in that area. Seven annual rounds with ivermectin and albendazole were given between 2009 and 2015 with a population coverage of over 70%. Participants of the previous study took part in a follow-up activity in 2019 to measure the effect of this governmental activity.FindingsOne thousand two hundred and ninety nine inhabitants of Kyela district in Southwest Tanzania aged 14 to 65 years who had participated in the study activities in 2009 were revisited in 2010/11 and 2019. Among this group, the prevalence of lymphatic filariasis of the 14–65 years olds in 2009 was 35.1%. A follow-up evaluation in 2010/11 had shown a reduction to 27.7%. In 2019, after 7 years of annual treatment and an additional three years of surveillance, the prevalence had dropped to 1.7%, demonstrating successful treatment by the national control programme. Risk factors for W. bancrofti-infection were the occupation as farmer, male sex, and older age. Most infected individuals in the 2019 follow-up study already had a positive test for filarial antigen in 2009 and/or 2010/11.ConclusionsThis data supports the findings of the Tanzanian Neglected Tropical Disease Control Programme (NTDCP), who conducted Transmission Assessment Surveys and found an impressive reduction in the prevalence of LF in children. Our results complement this data by showing a similar decrease in prevalence of LF in the adult population in the same area. The elimination of LF seems achievable in the near future. 相似文献
7.
Miftahudin Ross K Ma XF Mahmoud AA Layton J Milla MA Chikmawati T Ramalingam J Feril O Pathan MS Momirovic GS Kim S Chema K Fang P Haule L Struxness H Birkes J Yaghoubian C Skinner R McAllister J Nguyen V Qi LL Echalier B Gill BS Linkiewicz AM Dubcovsky J Akhunov ED Dvorák J Dilbirligi M Gill KS Peng JH Lapitan NL Bermudez-Kandianis CE Sorrells ME Hossain KG Kalavacharla V Kianian SF Lazo GR Chao S Anderson OD Gonzalez-Hernandez J Conley EJ Anderson JA Choi DW Fenton RD Close TJ McGuire PE 《Genetics》2004,168(2):651-663
A total of 1918 loci, detected by the hybridization of 938 expressed sequence tag unigenes (ESTs) from 26 Triticeae cDNA libraries, were mapped to wheat (Triticum aestivum L.) homoeologous group 4 chromosomes using a set of deletion, ditelosomic, and nulli-tetrasomic lines. The 1918 EST loci were not distributed uniformly among the three group 4 chromosomes; 41, 28, and 31% mapped to chromosomes 4A, 4B, and 4D, respectively. This pattern is in contrast to the cumulative results of EST mapping in all homoeologous groups, as reported elsewhere, that found the highest proportion of loci mapped to the B genome. Sixty-five percent of these 1918 loci mapped to the long arms of homoeologous group 4 chromosomes, while 35% mapped to the short arms. The distal regions of chromosome arms showed higher numbers of loci than the proximal regions, with the exception of 4DL. This study confirmed the complex structure of chromosome 4A that contains two reciprocal translocations and two inversions, previously identified. An additional inversion in the centromeric region of 4A was revealed. A consensus map for homoeologous group 4 was developed from 119 ESTs unique to group 4. Forty-nine percent of these ESTs were found to be homoeologous to sequences on rice chromosome 3, 12% had matches with sequences on other rice chromosomes, and 39% had no matches with rice sequences at all. Limited homology (only 26 of the 119 consensus ESTs) was found between wheat ESTs on homoeologous group 4 and the Arabidopsis genome. Forty-two percent of the homoeologous group 4 ESTs could be classified into functional categories on the basis of blastX searches against all protein databases. 相似文献
8.
Martins João Paulo Rodrigues de Almeida Rodrigues Luiz Carlos Santos Elizangela Rodrigues Gontijo Andreia Barcelos Passos Lima Falqueto Antelmo Ralph 《In vitro cellular & developmental biology. Plant》2020,56(3):350-361
In Vitro Cellular & Developmental Biology - Plant - In vitro culture conditions have a major impact on the physiology and anatomy of micropropagated plants. Sucrose plays a very important role... 相似文献
9.
Waldesse?Stoch?Rosa Jo?o?Paulo?Rodrigues?MartinsEmail author Elizangela?Santos?Rodrigues Luiz?Carlos?de?Almeida Rodrigues Andreia?Barcelos?Passos?Lima?Gontijo Antelmo?Ralph?Falqueto 《Plant Cell, Tissue and Organ Culture》2018,133(3):339-350
During the in vitro multiplication phase, the employment of cytokinins may be necessary to induce side shoots of many plant species. However, the mechanism by which cytokinins influence the physiology of plants in vitro is not well understood. Therefore, the objective of this study was to assess the influence of two cytokinins in function of concentration on the o photosynthetic apparatus performance and the stomatal functionality of Aechmea blanchetiana during in vitro multiplication. Plants previously established in vitro were transferred to MS culture media supplemented with 6-benzylaminopurine (BAP) or 6-furfurylaminopurine (kinetin—KIN) at concentration of 0, 5, 10, 15 or 20 µM. After 60 days of exposure to the plant growth regulators, the multiplication rate, photosynthetic apparatus performance and stomatal functionality were assessed. The use of KIN did not induce the formation of microshoots. On the other hand, the shoot number increased with rising BAP concentration. There was a reduction of the maximum fluorescence (Fm) and maximum quantum yield (φP0) as a function of concentration of cytokinins. The most pronounced decrease was observed in the microshoots grown with KIN. The increase in concentration of cytokinins induced greater absorption flux (ABS/RC), trapping flux (TR0/RC) and dissipation flux (DI0/RC) of energy per reaction center. The stomatal functionality declined with rising cytokinin concentration. The use of KIN is not recommended for in vitro multiplication of this species. The use of BAP at low concentrations assures a multiplication rate with lower degree of disorders in the photosynthetic apparatus of the formed microshoots. 相似文献
10.
Inge Kroidl Elmar Saathoff Lucas Maganga Petra Clowes Leonard Maboko Achim Hoerauf Williams H. Makunde Antelmo Haule Prisca Mviombo Bettina Pitter Neema Mgeni Joseph Mabuye Dickens Kowuor Upendo Mwingira Mwelecele N. Malecela Thomas L?scher Michael Hoelscher 《PLoS neglected tropical diseases》2016,10(8)