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21.
This communication reports on the Mycetoma Research Centre of the University of Khartoum, Sudan experience on 6,792 patients seen during the period 1991–2014.The patients were predominately young (64% under 30 years old) males (76%). The majority (68%) were from the Sudan mycetoma belt and 28% were students. Madurella mycetomatis eumycetoma was the most common type (70%). In 66% of the patients the duration of the disease was less than five years, and 81% gave a history of sinuses discharging mostly black grains (78%). History of trauma at the mycetoma site was reported in 20%. Local pain was reported in 27% of the patients, and only 12% had a family history of mycetoma. The study showed that 57% of the patients had previous surgical excisions and recurrence, and only 4% received previous medical treatment for mycetoma. Other concomitant medical diseases were reported in 4% of the patients. The foot (76%) and hand (8%) were the most commonly affected sites. Less frequently affected sites were the leg and knee (7%), thigh (2%), buttock (2%) and arm and forearm (1%). Rare sites included the chest wall, head and neck, back, abdominal wall, perineum, oral cavity, tongue and eye. Multiple sites mycetoma was recorded in 135 (2%) of cases. At presentation, 37% of patients had massive lesions, 79% had sinuses, 8% had local hyper-hydrosis at the mycetoma lesion, 11% had regional lymphadenopathy, while 6% had dilated tortuous veins proximal to the mycetoma lesions. The diagnosis of mycetoma was established by combined imaging techniques and cytological, histopathological, serological tests and grain culture. Patients with actinomycetoma received a combination of antimicrobial agents, while eumycetoma patients received antifungal agents combined with various surgical excisions. Surgical excisions in the form of wide local excision, debridement or amputation were done in 807 patients, and of them 248 patients (30.7%) had postoperative recurrence. Different types of amputations were done in 120 patients (1.7%).  相似文献   
22.
Mycetoma is a unique neglected tropical disease which is endemic in what is known as the “mycetoma belt”. The disease has many devastating impacts on patients and communities in endemic area and is characterised by massive deformity, destruction and disability. Mycetoma is commonly seen in the foot and hand and less frequent in other parts of the body. Mycetoma of the head and neck is a rarity and is associated with high morbidity and even mortality if not treated early. In this communication we report on 49 patients with head and neck mycetoma followed up at the Mycetoma Research Centre in Khartoum. Most of the reported patients had actinomycetoma and the majority were young adult males from mycetoma endemic areas in the Sudan. Most of them were students, farmers and workers. Prior to presentation the majority had long disease duration and the cause was multifactorial. Advanced disease with massive lesion, deformity and disability was the common presentation. There was no obvious history of local trauma, familial tendency or other predisposing factor identified in this group of patients. MRI and CT scan were the most accurate diagnostic tools to determine the disease extent. The treatment outcome was rather poor and characterised by low cure rate, poor outcome and high follows-up dropout. Such a gloomy outcome calls for structured and objective health education programs.  相似文献   
23.
Cell-penetrating peptides (CPPs) have shown great potency for cargo delivery both in vitro and in vivo. Different biologically relevant molecules need to be delivered into appropriate cellular compartments in order to be active, for instance certain drugs/molecules, e.g. antisense oligonucleotides, peptides, and cytotoxic agents require delivery into the cytoplasm. Assessing uptake mechanisms of CPPs can help to develop novel and more potent cellular delivery vectors, especially in cases when reaching a specific intracellular target requires involvement of a specific internalization pathway. Here we measure the overall uptake kinetics, with emphasis on cytoplasmic delivery, of three cell-penetrating peptides M918, TP10 and pVec using a quenched fluorescence assay. We show that both the uptake levels and kinetic constants depend on the endocytosis inhibitors used in the experiments. In addition, in some cases only the internalization rate is affected by the endocytosis inhibitors while the total uptake level is not and vice versa, which emphasizes importance of kinetic studies when assessing the uptake mechanisms of CPPs. Also, there seems to be a correlation between lower total cellular uptake and higher first-order rate constants. Furthermore, this may indicate simultaneous involvement of different endocytic pathways with different efficacies in the internalization process, as hypothesized but not shown earlier in an uptake kinetics assay.  相似文献   
24.
A new genus, Altihoratosphaga, is erected for species formerly assigned to Horatosphaga Schaum, 1853, and a new species is described. Four species are included in Altihoratosphaga: Altihoratosphaga nomima (Karsch, 1896), Altihoratosphaga montivaga ( Sjöstedt, 1909 ), Altihoratosphaga nou (Hemp, 2007) and Altihoratosphaga hanangensis sp. nov. All four species are restricted to Tanzanian localities, and, except for A. nomima, for which no ecological data are available, are confined to montane forest habitats. Data on ecology, acoustics, chromosomes, and molecular relationships are provided, as well as a key to Altihoratosphaga species. The present‐day distribution of Altihoratosphaga species suggests former migration events at times when wetter and colder climatic fluctuations favoured connections between montane forest communities, which today are isolated, enabling flightless taxa such as Altihoratosphaga and Monticolaria to spread. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 66–82.  相似文献   
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In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS) to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline environment. Results revealed that the addition of FYM (5–10 ton ha-1 ) in Cd-contaminated soil significantly increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1 ) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed that incorporation of FYM (5–10 ton ha-1 ) performed better to enhance wheat growth and yield by remediating Cd. Thus, the application of FYM (5–10 ton ha-1 ) reduced the toxicity induced by Cd to plants by declining its uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy alkaline polluted soil.  相似文献   
27.
Drought stress was imposed on two sets of Arabidopsis thaliana genotypes grown in sand under short‐day conditions and analysed for several shoot and root growth traits. The response to drought was assessed for quantitative trait locus (QTL) mapping in a genetically diverse set of Arabidopsis accessions using genome‐wide association (GWA) mapping, and conventional linkage analysis of a recombinant inbred line (RIL) population. Results showed significant genotype by environment interaction (G×E) for all traits in response to different watering regimes. For the RIL population, the observed G×E was reflected in 17 QTL by environment interactions (Q×E), while 17 additional QTLs were mapped not showing Q×E. GWA mapping identified 58 single nucleotide polymorphism (SNPs) associated with loci displaying Q×E and an additional 16 SNPs associated with loci not showing Q×E. Many candidate genes potentially underlying these loci were suggested. The genes for RPS3C and YLS7 were found to contain conserved amino acid differences when comparing Arabidopsis accessions with strongly contrasting drought response phenotypes, further supporting their candidacy. One of these candidate genes co‐located with a QTL mapped in the RIL population.  相似文献   
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29.
A review is presented of genetic strategies deployed in a 3-yr project on drought tolerance in barley. Data were collected on genetic, physiological and agronomic traits in non-irrigated and irrigated field trials in Egypt, Morocco and Tunisia. A wide range of barley germplasm (developed from African and European cultivars, adapted landraces and wild barleys) was tested, and positive traits were found in each gene pool. The contrasting environments of the three North African countries had major effects on plant/genotype performance. Genetic effects were also detected, as were genotype × environment interactions. A range of strategies were deployed to investigate the physiology and genetics of quantitative traits associated with field performance. Quantitative trait locus (QTL) analysis was performed using backcross lines, recombinant inbred lines and doubled haploid mapping populations. A detailed genetic map was generated in the Tadmor × (ER/Apm) recombinant inbred lines, an important mapping population specifically developed by ICARDA (Centre for Agricultural Research in Dry Areas) and CIMMYT (International Maize and Wheat Improvement Center) to study drought. Quantitative trait loci (QTLs) for grain yield and other important morphological and physiological traits were also identified in a population of doubled haploids derived from F2BCj plants from a cross between a cultivar and a wild barley accession. Significantly, the wild parental line was found to contribute a number of positive alleles for yield. Effects of major developmental genes could explain many of the responses observed. QTLs were found to cluster around major genes controlling flowering time (sghI), plant stature (sdwI and arie.GP) and ear type (vrsl), and it is highly likely that the associations represent pleiotropic effects. Some QTLs were associated with candidate genes such as dehydrins and rubisco activase. One of the most significant results was the identification and generation of material that out performed the best local standards in the three participating North African countries; the selected lines have now entered local breeding programmes. The strategies adopted provided information on physiological traits, genotypes and genetic markers that could be used for marker-assisted selection. Target QTLs and their associated genetic markers may be deployed in marker assisted selection programmes to match crop phenology to the field environment.  相似文献   
30.
Time-resolved absorption measurements of the formation and decay kinetics of the M (deprotonated) photocycle intermediate of bR purple membranes entrapped within a dried xerogel glass have been investigated. The dramatic change observed for the M state decay time is in contrast to the relatively insensitive half life reported for the M intermediate of the D96N mutant entrapped within a dried sol-gel glass. The decay kinetics of the M intermediate was observed to slow by a factor of almost 100 when the solvent was removed from the wet-gel to form the dry xerogel glass. Very long aging times for wet-gels resulted in highly biexponential M state decay kinetics. Upon drying, the M state formation rate initially decreased relative to that in solution before increasing in the dry xerogel to a formation rate nearly three times faster than in solution.  相似文献   
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