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1.
Six species of the genus Eumonhystera, one of which is new to science, are described from bottom samples of Lake Tana and two associated rivers, River Abbay and R. Gelda, Ethiopia. E. geraerti n.sp. can be identified by being the only species in the genus that combines very posteriorly positioned vulva [V% = 68.2 ± 0.7 (67.3–69.3)] with very anteriorly positioned amphids (Amph-ABE/LRW = 0.8). The other five species encountered, E. dispar (Bastian, 1865) Andrássy, 1981, E. filiformis (Bastian, 1865) Andrássy, 1981, E. pseudobulbosa (von Daday, 1896) Andrássy, 1981, E. mwerazii (Meyl, 1957) Andrássy, 1981, and E. vulgaris (de Man, 1880), Andrássy, 1981, are described in detail. The identities of some of the already described populations of E. dispar, E. filiformis and E. vulgaris are questioned and clearer and better ways of defining each of these three species are suggested. A peritrophic-like membrane on the outer side of the brush-border of the intestine of E. mwerazii, a species reported here for the first time out of its type locality, is reported. Also, scanning electronmicrographs of sectioned and entire specimens of E. mwerazii are presented. All species are reported from Ethiopia for the first time. 相似文献
2.
A Mycobacterium leprae-specific gene encoding an immunologically recognized 45 kDa protein 总被引:1,自引:0,他引:1
Tobias F. Rinke de Wit Josephine E. Clark-Curtiss Feseha Abebe Arend H. J. Kolk Anneke A. M. Janson Miranda van Agterveld Jelle E. R. Thole 《Molecular microbiology》1993,10(4):829-838
By screening a Mycobacterium leprae lambda gt11 expression library with a serum from an Ethiopian lepromatous leprosy (LL) patient a clone was isolated (LL4) belonging to hybridization group III of a panel of previously isolated M. leprae clones. Members of this hybridization group encode a serologically recognized 45 kDa protein. The complete DNA sequences of the partially overlapping clones LL4 and L1 (hybridization group III) are presented and these revealed the presence of an open reading frame (ORF) predicting a protein with a molecular size of 42 448 Da. Southern hybridizations on total genomic DNA of M. Ieprae, Mycobacterium tuberculosis and eight atypical mycobacteria showed that the LL4 DNA fragment is specific for M. Ieprae DNA even under low-stringency conditions. The M. Ieprae specificity of LL4 DNA was further confirmed by the polymerase chain reaction using four different sets of primers. Western blotting analyses showed that the M. Ieprae 45 kDa protein is frequently recognized by antibodies from leprosy patients and that this recognition is specific since no antibodies could be detected in sera of tuberculosis patients. T-cell proliferation assays also demonstrated T-cell recognition by leprosy patients and healthy contacts of the M. Ieprae 45 kDa protein. The specificity of the LL4 DNA region and the 45 kDa antigen that is encoded by hybridization group III could provide unique tools for the development of M. Ieprae-specific immunological and DNA reagents. 相似文献
3.
Andrew J. Bladon Paul F. Donald Samuel E.I. Jones Nigel J. Collar Jarso Deng Galgalo Dadacha Yilma D. Abebe Rhys E. Green 《Ibis》2019,161(3):546-558
Climate may influence the distribution and abundance of a species through a number of demographic and ecological processes, but the proximate drivers of such responses are only recently being identified. The Ethiopian Bush‐crow Zavattariornis stresemanni is a starling‐like corvid that is restricted to a small region of southern Ethiopia. It is classified as Endangered in the IUCN Red List of globally threatened species. Previous work suggested that this range restriction is almost perfectly defined by a climate envelope that is cooler than surrounding areas, but the proximate mechanism remains unexplained. The heavily altered habitats which the species inhabits are widespread across Africa, and recent work has shown that the Bush‐crow is behaviourally adaptable and has a catholic diet. We assess whether its enigmatic distribution can be explained by behavioural responses to the higher temperatures that surround its current range. Using environmental niche models and field observations of thermally mediated behaviour, we compare the range restriction and behavioural thermoregulation of the Ethiopian Bush‐crow with those of two sympatric control species that are similar in size and ecology, but have much larger ranges that include hotter environments. White‐crowned Starling Lamprotornis albicapillus and Superb Starling L. superbus occupy similar habitats to the Ethiopian Bush‐crow and all three frequently forage together. We found that the Bush‐crow's range is limited primarily by temperature, with a secondary effect of dry season rainfall, whereas the ranges of the two starling species are better predicted by wet season rainfall alone. Bush‐crows exhibited panting behaviour and moved into the shade of trees at significantly lower ambient temperatures than did the starlings, and their food intake declined more steeply with increasing temperature. These results indicate that the limited geographical range of the Bush‐crow reflects an inability to cope with higher temperatures. This suggests that a species' response to climate change might not be easily predicted by its ecological generalism, and may represent an inherited debt from its evolutionary history. 相似文献
4.
Anne M. Estes David J. Hearn Emilie C. Snell-Rood Michele Feindler Karla Feeser Tselotie Abebe Julie C. Dunning Hotopp Armin P. Moczek 《PloS one》2013,8(11)
Insects feeding on plant sap, blood, and other nutritionally incomplete diets are typically associated with mutualistic bacteria that supplement missing nutrients. Herbivorous mammal dung contains more than 86% cellulose and lacks amino acids essential for insect development and reproduction. Yet one of the most ecologically necessary and evolutionarily successful groups of beetles, the dung beetles (Scarabaeinae) feeds primarily, or exclusively, on dung. These associations suggest that dung beetles may benefit from mutualistic bacteria that provide nutrients missing from dung. The nesting behaviors of the female parent and the feeding behaviors of the larvae suggest that a microbiome could be vertically transmitted from the parental female to her offspring through the brood ball. Using sterile rearing and a combination of molecular and culture-based techniques, we examine transmission of the microbiome in the bull-headed dung beetle, Onthophagus taurus. Beetles were reared on autoclaved dung and the microbiome was characterized across development. A ~1425 bp region of the 16S rRNA identified Pseudomonadaceae, Enterobacteriaceae, and Comamonadaceae as the most common bacterial families across all life stages and populations, including cultured isolates from the 3rd instar digestive system. Finer level phylotyping analyses based on lepA and gyrB amplicons of cultured isolates placed the isolates closest to Enterobacter cloacae, Providencia stuartii, Pusillimonas sp., Pedobacter heparinus, and Lysinibacillus sphaericus. Scanning electron micrographs of brood balls constructed from sterile dung reveals secretions and microbes only in the chamber the female prepares for the egg. The use of autoclaved dung for rearing, the presence of microbes in the brood ball and offspring, and identical 16S rRNA sequences in both parent and offspring suggests that the O. taurus female parent transmits specific microbiome members to her offspring through the brood chamber. The transmission of the dung beetle microbiome highlights the maintenance and likely importance of this newly-characterized bacterial community. 相似文献
5.
Background
Diabetes mellitus is becoming one of the major causes of premature adult mortality in developing countries. However, there is a very little documentation of the morbidity trend in such countries.Objective
To assess the ten-year trend of diabetes mellitus at Gondar University Teaching Referral Hospital, northwest Ethiopia.Methods
A hospital-based retrospective record review was done at the main referral hospital in northwest Ethiopia. Data were obtained from medical records of all registered diabetic patients in the Diabetic Follow up Clinic between 2000 and 2009. An Extended Mantel-Haenzel chi-square test for the linear trend was used to examine the trend over time.Result
Out of the total 354,524 patients who visited the Outpatient Department of the hospital during the study period, 1553 (4.4/1000) were diabetes patients, of which 50.1% was type 1 and 49.9% type 2 diabetes mellitus. The average increase in the proportion of both Type 1 and Type 2 diabetes mellitus cases between 2000 and 2009 was 125%. The mean (±SD) age for Type 1 diabetes mellitus was 29.1 (±12), and 53.5 (±12) for Type 2 diabetes. Overall 42.5% of the diabetes mellitus patients were female and 31.7% were rural residents. The mean body mass index for both type of diabetes mellitus increased from 15.9 to 18.3 kg for type 1 and from 23.8 to 24.6 for type 2 between 2000 and 2009, respectively.Conclusion
The number of diabetes mellitus cases seen at Gondar Referral Hospital is rising steadily. A comprehensive diabetes prevention, treatment, and care program is needed to improve the quality of life of the increasing diabetes mellitus cases in Ethiopia. 相似文献6.
Kelemework Adane Mark Spigt Semaw Ferede Tsehaye Asmelash Markos Abebe Geert-Jan Dinant 《PloS one》2016,11(2)
Introduction
Prison settings have been often identified as important but neglected reservoirs for TB. This study was designed to determine the prevalence of undiagnosed pulmonary TB and assess the potential risk factors for such TB cases in prisons of the Tigray region.Method
A cross-sectional study was conducted between August 2013 and February 2014 in nine prisons. A standardized symptom-based questionnaire was initially used to identify presumptive TB cases. From each, three consecutive sputum samples were collected for acid-fast bacilli (AFB) microscopy and culture. Blood samples were collected from consented participants for HIV testing.Result
Out of 809 presumptive TB cases with culture result, 4.0% (95% CI: 2.65–5.35) were confirmed to have undiagnosed TB. The overall estimated point prevalence of undiagnosed TB was found to be 505/100,000 prisoners (95% CI: 360–640). Together with the 27 patients who were already on treatment, the overall estimated point prevalence of TB would be 793/100,000 prisoners (95% CI: 610–970), about four times higher than in the general population. The ratio of active to passive case detection was 1.18:1. The prevalence of HIV was 4.4% (36/809) among presumptive TB cases and 6.3% (2/32) among undiagnosed TB cases. In a multivariate logistic regression analysis, chewing Khat (adjusted OR = 2.81; 95% CI: 1.02–7.75) and having had a close contact with a TB patient (adjusted OR = 2.18; 95% CI: 1.05–4.51) were found to be predictors of undiagnosed TB among presumptive TB cases.Conclusions
This study revealed that at least half of symptomatic pulmonary TB cases in Northern Ethiopian prisons remain undiagnosed and hence untreated. The prevalence of undiagnosed TB in the study prisons was more than two folds higher than in the general population of Tigray. This may indicate the need for more investment and commitment to improving TB case detection in the study prisons. 相似文献7.
Marie J. Zwetsloot Johannes Lehmann Taryn Bauerle Steven Vanek Rachel Hestrin Abebe Nigussie 《Plant and Soil》2016,408(1-2):95-105
Aims
The objectives of this study were to evaluate (1) the fertilizer potential of bone char, (2) the effects of wood biochar on plant-available phosphorus (P), and (3) the role of root-mycorrhizae-biochar interactions in plant P acquisition from a P-fixing soil.Methods
Incubation and pot experiments were conducted with a P-fixing soil and maize with or without root hairs and arbuscular mycorrhizae (AM) inoculation. Olsen-, resin-P and plant P accumulation were used to estimate P availability from bone char, co-pyrolyzed bone char-wood biochar, and separate bone char and wood biochar additions produced at 60, 350 and 750 °C, and Triple Superphosphate (TSP).Results
Maize inoculated with AM showed similar P accumulation when fertilized with either 750 °C bone char or TSP. Pyrolyzing bone did not increase extractable P in soil in comparison to unpyrolyzed bone, apart from a 67 % increase in resin-extractable P after additions of bone char pyrolyzed at 350 °C. Despite greater Olsen-P extractability, co-pyrolysis of bone with wood reduced maize P uptake. Wood biochars reduced resin-P from bone char by 14–26 %, whereas oven-dried wood increased resin-P by 23 %.Conclusions
Bone char is an effective P fertilizer, especially if root-AM interactions are simultaneously considered. Biochar influences plant access to soil P and requires careful management to improve P availability.8.
Effects of solvent polarity on the absorption and fluorescence spectra of chlorogenic acid and caffeic acid compounds: determination of the dipole moments
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The effects of solvent polarity on absorption and fluorescence spectra of biologically active compounds (chlorogenic acid (CGA) and caffeic acids (CA)) have been investigated. In both spectra pronounced solvatochromic effects were observed with shift of emission peaks larger than the corresponding UV‐vis electronic absorption spectra. From solvatochromic theory the ground and excited‐state dipole moments were determined experimentally and theoretically. The differences between the excited and ground state dipole moment determined by Bakhshiev, Kawski–Chamma–Viallet and Reichardt equations are quite similar. The ground and excited‐state dipole moments were determined by theoretical quantum chemical calculation using density function theory (DFT) method (Gaussian 09) and were also similar to the experimental results. The HOMO‐LUMO energy band gaps for CGA and CFA were calculated and found to be 4.1119 and 1.8732 eV respectively. The results also indicated the CGA molecule is more stable than that of CFA. It was also observed that in both compounds the excited state possesses a higher dipole moment than that of the ground state. This confirms that the excited state of the hydroxycinnamic compounds is more polarized than that of the ground state and therefore is more sensitive to the solvent. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
Previous work with model transgenic plants has demonstrated that cellular accumulation of mannitol can alleviate abiotic stress. Here, we show that ectopic expression of the mtlD gene for the biosynthesis of mannitol in wheat improves tolerance to water stress and salinity. Wheat (Triticum aestivum L. cv Bobwhite) was transformed with the mtlD gene of Escherichia coli. Tolerance to water stress and salinity was evaluated using calli and T(2) plants transformed with (+mtlD) or without (-mtlD) mtlD. Calli were exposed to -1.0 MPa of polyethylene glycol 8,000 or 100 mM NaCl. T(2) plants were stressed by withholding water or by adding 150 mM NaCl to the nutrient medium. Fresh weight of -mtlD calli was reduced by 40% in the presence of polyethylene glycol and 37% under NaCl stress. Growth of +mtlD calli was not affected by stress. In -mtlD plants, fresh weight, dry weight, plant height, and flag leaf length were reduced by 70%, 56%, 40%, and 45% compared with 40%, 8%, 18%, and 29%, respectively, in +mtlD plants. Salt stress reduced shoot fresh weight, dry weight, plant height, and flag leaf length by 77%, 73%, 25%, and 36% in -mtlD plants, respectively, compared with 50%, 30%, 12%, and 20% in +mtlD plants. However, the amount of mannitol accumulated in the callus and mature fifth leaf (1.7-3.7 micromol g(-1) fresh weight in the callus and 0.6-2.0 micromol g(-1) fresh weight in the leaf) was too small to protect against stress through osmotic adjustment. We conclude that the improved growth performance of mannitol-accumulating calli and mature leaves was due to other stress-protective functions of mannitol, although this study cannot rule out possible osmotic effects in growing regions of the plant. 相似文献
10.
昆虫嗅觉相关蛋白及嗅觉识别机理研究概述 总被引:1,自引:0,他引:1
嗅觉是昆虫产生行为的基础之一,在长期进化的过程中昆虫形成了复杂的嗅觉系统,完成这一过程,需要有多种与嗅觉相关的蛋白参与,包括气味结合蛋白、化学感受蛋白、气味受体和感觉神经元膜蛋白等。了解昆虫感受外界信息的嗅觉机制可以帮助我们更好地理解昆虫识别配偶、天敌及寻找食物来源、产卵场地等行为特征,为进一步调控昆虫的行为、防控害虫侵袭、保护和利用有益昆虫奠定基础。本文综述了昆虫嗅觉相关的几类重要蛋白的生化特性和生理功能,并对昆虫气味分子的识别机制、气味分子在昆虫体内运输机制的最新研究进展进行了概述。 相似文献