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101.
Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels
of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining
serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited
the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium
were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had
significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those
in non-pregnant women (P < 0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P < 0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant
women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective
of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium,
and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative
pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P < 0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant
women, respectively. Only 25.9% of the pregnant women and 44.7% of the non-pregnant women were not deficient in any of the
micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants
the need for strategies on prevention and control of the deficiencies. 相似文献
102.
Diets of the African Civet Civettictis civetta (Schreber, 1778) in selected coffee forest habitat,south‐western Ethiopia 下载免费PDF全文
Tadesse Habtamu Afework Bekele Raya Ahmed Tsegaye Gadisa Belay Birlie Taye Tolemariam Berhanu Belay 《African Journal of Ecology》2017,55(4):573-579
Feeding ecology of the African civet, Civettictis civetta (Schreber, 1778), was studied in selected coffee forest habitat for two seasons between December 2012 and October 2013. The study was conducted in Limu Seka district, south‐west Ethiopia. Faecal analysis was employed to assess the diet spectrum, seasonal abundance and relative importance of food items. Over 55 different food items were identified from the analysis of 387 scat samples collected during the dry and wet seasons. In the coffee forest habitat, African civets showed omnivorous feeding habit with plant‐to‐animal diet biomass ratio of 1 : 1.36. A slight diet specialization was observed during the wet season (BA = 0.46) favouring animal prey. However, during the dry season, they showed generalist feeding habit (BA = 0.87) with more plant biomass in their diet. With over 64% occurrence and 14.4% biomass, coffee berries significantly contributed to the civets dry season plant diets. The excreted coffee beans, after civets ingested ripe coffee berries, are the tastiest product used by farmers for consumption and market. Seasonal collection of civet coffee from coffee forest floor economically supports the farmers while increasing the importance of civets in the habitat and hence contributing for its conservation. 相似文献
103.
104.
Martin?MühlingEmail author Amha?Belay Brian?A.?Whitton 《Journal of applied phycology》2005,17(2):129-135
Thirty-five clonal, axenic Arthrospira strains were screened for their ability to grow heterotrophically on six carbon sources (20 mM). Glucose (34 strains) and fructose (24 strains) were the only substrates permitting growth in the dark. In some assays, however, not every replicate grew and, in at least one strain (D867), repeat assays over 2 years on material maintained in the light indicated that the ability to use fructose in the dark had become lost. Four further strains from other culture collections were compared, because they are presumed duplicates of three of the main set of strains; in at least three cases the duplicates of a pair differed in their ability to use fructose in the dark. In another comparison, where straight and helical morphotypes of the same strain could be compared, two of the four straight morphotypes (including one duplicate strain) grew with glucose in the dark, whereas none of the helical morphotypes did so. It is suggested that genetic drift has led to losses in the ability to grow heterotrophically in some strains.Ten of the main set of strains were tested for their ability to grow photoheterotrophically with four of the carbon sources (glucose, maltose, fructose, sucrose). All grew with glucose and maltose, but none with fructose or sucrose, in spite of the fact that eight (of this subset) grew with fructose in the dark. Sucrose led to most of a culture lysing, but often with short fragments of trichome surviving and subsequently giving rise to a normal culture. All the surviving cells in the transitory stage showed the presence of large intrathylakoidal granules, which had disappeared by the time that the culture had returned to a healthy state. Bleaching and recovery were more rapid at 70 than 10 μmol photon m−2 s−1. The presence of DCMU prevented this recovery. There was no bleaching when an inoculum of the recovered material was subcultured to medium with sucrose. 相似文献
105.
Supplementation of minimal medium inoculated with bacterial cultures with norepinephrine, epinephrine, dopamine, or isoproterenol resulted in marked increases in growth compared to controls. Norepinephrine and dopamine had the greatest enhancing effects on growth of cultures of Pseudomonas aeruginosa and Klebsiella pneumoniae, while epinephrine and isoproterenol also enhanced growth to a lesser extent. The growth of Escherichia coli in the presence of norepinephrine was greater than growth in the presence of the three other neurochemicals used in the study. Growth of Staphylococcus aureus was also enhanced in the presence of norepinephrine, but not to the same degree as was the growth of gram negative bacteria. Addition of culture supernatants from E. coli cultures that had been grown in the presence of norepinephrine was able to enhance the growth of K. pneumoniae. Addition of the culture supernatant fluid culture from E. coli cultures that had been grown in the presence of norepinephrine did not enhance growth of P. aeruginosa or S. aureus. Culture supernatant fluids from bacteria other than E. coli grown in the presence of norepinephrine were not able to enhance the growth of any bacteria tested. The results suggest that catecholamines can enhance growth of pathogenic bacteria, which may contribute to development of pathogenesis; however, there is no uniform effect of catecholamines on bacterial growth. 相似文献
106.
Spatial analysis of cell death and Hsp70 induction in brain, thymus, and bone marrow of the hyperthermic rat 下载免费PDF全文
Heat shock response and programmed cell death are cellular reactions to stressful stimuli. Previous studies have not correlated these responses in vivo at the spatial level in mammalian tissues. This study uses a dual procedure involving immunocytochemistry for Hsp70 localization and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end-labeling (TUNEL) assay for cell death to correlate the pattern of stress-inducible Hsp70 and cell death at the cellular level. After whole-body hyperthermia in the rat, an increase in Hsp70-positive cells and TUNEL-positive cells was noted in brain, thymus, and bone marrow. However, 2 populations of cells were apparent in the tissues examined, those inducing Hsp70 and those triggered into programmed cell death. Cells that were both Hsp70 positive and TUNEL positive were rarely detected. In tissues of the intact mammal, cells that induce Hsp70 after whole-body hyperthermia were not triggered into programmed cell death. 相似文献
107.
Smith CM Belay T Stauffer C Stary P Kubeckova I Starkey S 《Journal of economic entomology》2004,97(3):1112-1117
The Russian wheat aphid, Diuraphis noxia (Mordvilko), is a serious worldwide pest of wheat and barley. Russian wheat aphid populations from Hungary, Russia, and Syria have previously been identified as virulent to D. noxia (Dn) 4, the gene in all Russian wheat aphid-resistant cultivars produced in Colorado. However, the virulence of Russian wheat aphid populations from central Europe, North Africa, and South America to existing Dn genes has not been assessed. Experiments with plants containing several different Dn genes demonstrated that populations from Chile, the Czech Republic, and Ethiopia are also virulent to Dn4. The Czech population was also virulent to plants containing the Dnx gene in wheat plant introduction PI220127. The Ethiopian population was also virulent to plants containing the Dny gene in the Russian wheat aphid-resistant 'Stanton' produced in Kansas. The Chilean and Ethiopian populations were unaffected by the antibiosis resistance in Dn4 plants. There were significantly more nymphs of the Chilean population on plants of Dn4 than on Dn6 plants at both 18 and 23 d postinfestation, and the Ethiopian population attained a significantly greater weight on Dn4 plants than on plants containing Dn5 or Dn6. These newly characterized virulent Russian wheat aphid populations pose a distinct threat to existing or proposed wheat cultivars possessing Dn4. 相似文献
108.
M. V. Mina F. N. Shkil K. F. Dzerzhinskii Belay Abdissa A. N. Mironovsky D. V. Kapitanova 《Journal of Ichthyology》2012,52(11):821-837
Results of a long-time (2005?C2011) experiment in crossing and rearing the large African barbs from Lake Tana (Ethiopia) are presented. One may conclude that progeny from homonomic crossings of large-mouthed barbs acquire diagnostic traits of their parental morphotype at different age. Some males originated from different crossings reached sexual maturity before acquiring diagnostic traits of a certain morphotype. Siblings from both homonomic and heteronomic crossings living in the same conditions considerably differed both in external and in skull characters. Differences both in external and skull characters between some siblings originated from a homonomic crossing that lived in a pond and those that lived in aquaria were equivalent to the differences between moiphotypes. 相似文献
109.
Ha YS Lee HY An GI Kim J Kwak W Lee EJ Lee SM Lee BH Kim IS Belay T Lee W Ahn BC Lee J Yoo J 《Bioorganic & medicinal chemistry》2012,20(14):4330-4335
Bladder cancer is the second most common cancer of the urinary tract, however the invasive cystoscopy is still the standard technique for diagnosis and surveillance of bladder cancer. Herein, we radiolabel bladder cancer specific peptide with radioactive iodine ((131/124)I) and evaluate its potential as a new radiopharmaceutical for the non-invasive diagnosis of bladder cancer. A 9-mer bladder cancer specific peptide (BP) was conjugated with tyrosine and cyclized by disulfide bond formation to give Y-BP, which was further radioiodinated to give [(131/124)I]Y-BP in good radiochemical yield. The biodistribution data showed the high selectivity of [(124)I]Y-BP in HT1376 human bladder cancer xenograft models with a tumor-to-muscle ratio of 6.2. This tumor targeting was not observed in control B16F10 melanoma tumor models. In microPET studies, while the control scrambled peptide, [(124)I]Y-sBP, did not accumulate in either the bladder cancer or melanoma, [(124)I]Y-BP showed high tumor uptake only in animals with HT1376 bladder cancer cells. Furthermore, [(124)I]Y-BP showed superior bladder cancer uptake even compared to most commonly used cancer imaging tracer, [(18)F]FDG. The experimental results suggest the potential of [(124)I]Y-BP as a new radiopharmaceutical for the non-invasive diagnosis of bladder cancer with high binding affinity and selectivity. 相似文献
110.
Dagimawie Tadesse Alemseged Abdissa Mekidim Mekonnen Tariku Belay Asrat Hailu 《PLoS neglected tropical diseases》2021,15(8)
BackgroundVisceral leishmaniasis is a disease caused by disseminated Leishmania donovani infection which affects almost half a million people annually. Most of the patients are reported from the Indian sub-continent, Eastern Africa and Brazil. In this study, we aimed to determine the levels of antibodies and cytokines in visceral leishmaniasis patients and to examine associations of parasitemia with the clinical states of patients. A prospective study was carried out, enrolling a total of 48 active VL patients who were evaluated before, during different time points and, three months after treatment. Serum cytokine concentrations, antibody levels, parasitemia, laboratory (hematologic and biochemical) measurements, and clinical parameters were assessed.ResultsCounts of WBC and platelets, and measurements of hemoglobin (Hb) increased during treatment (P ≤ 0.05). Elevated levels of circulating IL-10, IFN-γ, and TGF-β1 were measured before treatment. The observed increase in serum IL-10 remarkably declined within 7 days after the start of treatment. Anti-leishmanial antibody index (AI) was high in all VL patients irrespective of spleen aspirate parasite grade before treatment and at different times during treatment. However, a significant (P ≤ 0.05) decrease of AI was observed 120 days post-treatment. IL-2 serum levels were below the detection limit at all sampling points.ConclusionsThe present results suggest that IL-10, IFN-γ, and TGF-β1 can be used as markers of active visceral leishmaniasis. In addition, measuring circulating cytokines concentrations, particularly IL-10, in combination with other clinical evaluations, could be used as criteria for the cure. The observation that a high serum concentration of IFN-gamma at baseline was associated with low parasitemia deserves further investigations. 相似文献