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51.
52.
The Opuntia (prickly pear) genus, an important horticultural crop in Mexico, is essentially a fruit crop with two variants: sweet (“tunas”) or acid (“xoconostles”) fruits; it is also a source of vegetables “nopalitos” or fodder for livestock, among other uses. Its taxonomical classification has been reported as complex, although few studies on the genetic structure of Mexican Opuntia are available, and genetic differences between the two types of fruits are unknown. Opuntia genotype identification and classification are still mainly based on morphological characters. In this study, the genetic diversity of Mexican Opuntia germplasm with agronomic and economic importance was revealed, using 88 accessions and 13 SSR markers, in an attempt to explore the genetic relationships among them. A total of 159 alleles were detected ranging from 7 to 23 per locus with an average of 12.2. The SSR markers generated unique fingerprints for each Opuntia accession confirming their usefulness for genetic analysis. The accessions’ grouping was defined by several complementary clustering methods, and the moderate incongruences between the different methods did not influence the overall clustering. DAPC and STRUCTURE analyses grouped the accessions into five groups, thus confirming the incorrect delimitation of species in this genus. The following species had no clear boundaries: Opuntia ficus-indica, Opuntia albicarpa, Opuntia megacantha, Opuntia streptacantha, Opuntia lasiacantha, and Opuntia hyptiacantha. However, Opuntia robusta was separated from the rest of the species. Opuntia joconostle and Opuntia matudae, which produce acid fruits, tended to differ from the others. Median-joining simulation classified all genotypes into a complex network, and both linear and reticular ties between Mexican Opuntia genotypes were revealed. The genetic distance revealed in the present study shows the importance of Mexican accessions for conservation and use in breeding programs.  相似文献   
53.
Haemorrhagic septicaemia caused by Pasteurella multocida is a major epizootic disease in cattle and buffaloes in developing countries with high morbidity and mortality rate. In the present study, a total of 88 P. multocida isolates were isolated from 256 nasopharyngeal swabs and lung tissues samples (34.4%) during the period from January, 2013 to March, 2014 from different governorates located in Egypt. Dead calves showed the highest percentage of P. multocida isolation followed by the emergency slaughtered calves, diseased calves then apparently healthy ones. These isolates were confirmed as P. multocida microscopically, biochemically by traditional tests and by API 20E commercial kit then by PCR. The percentages of positive serum samples using somatic antigen and micro-agglutination test at 1/1280 diluted serum were 10%, 54.49% and 0% in apparently healthy, diseased and emergency slaughtered samples, respectively whereas, the percentages using capsular antigen and indirect haemagglutination test were 40%, 60.89% and 60% in apparently healthy, diseased and emergency slaughtered samples, respectively. The ELISA showed the highest sensitivity for diagnosing P. multocida in apparently healthy, diseased and emergency slaughtered animals with percentages of 42%; 92.9% and 80%, respectively. The obtained results revealed that the ELISA using capsular antigen of P. multocida is a more sensitive and specific serological test for diagnosis of haemorrhagic septicaemia.  相似文献   
54.
IntroductionOral fluoroquinolones and tetracyclines are known to interact with divalent or trivalent cation-containing compounds (DTCCs) via chelation. The objective of this study is to describe the prevalence of these drug-drug interactions (DDIs) in an inpatient setting.MethodsA cross-sectional study of prospectively collected data were conducted at an academic tertiary care hospital. We included hospitalized adults who were receiving oral fluoroquinolones or tetracyclines with DTCCs in 2019. Our hospital uses electronic health records for medication ordering and handwritten medication administration records (MARs). The primary study outcome was the percentage of simultaneous administration of fluoroquinolones or tetracyclines with DTCCs, and the secondary outcome was the percentage of inappropriate separation time.ResultsAmong patients who received oral fluoroquinolones or tetracyclines, 47 patients (26.6%) were co-administered DTCCs and included in this study. Ciprofloxacin (n = 29; 61.7%) was the most commonly interacting antibiotic, followed by moxifloxacin (n = 12; 25.5%) and doxycycline (n = 6; 12.8%). The interacting DTCCs included iron-containing products and calcium-containing products, and half of the patients (n = 24; 51%) received DTCCs once daily. Most patients (n = 35; 74.5%) were found to receive oral fluoroquinolones or tetracyclines at the same time as DTCCs, while one (2.1%) received inappropriately separated DTCCs.ConclusionsDespite being a very known contraindicated DDI, the prevalence of simultaneous co-administration of oral fluoroquinolones or tetracyclines with polyvalent cations was extremely high in a hospital with handwritten MARs. Antimicrobial stewardship programs should target this DDI, and future studies should evaluate the impact of different practical solutions to this problem in different clinical settings.  相似文献   
55.
We have performed an exhaustive retrospective study in all surgical wards (54 services in 35 hospitals) which usually carry out surgical treatment of hydatic cysts in the country, covering the period between January 2001 and December 2005, in order to determine the annual surgical incidence of human cystic hydatidosis in Tunisia. A total of 6249 surgical interventions were recorded during the period 2001-2005. The highest proportion was recorded in the hospitals of Tunis District (42.9%). The service of thoracic surgery from Ariana hospital occupies the first rank (95%). The yearly incidence rate varies between 11 and 13.6 per 100,000. Calculated over the 5 years period, the incidence rate is 63.2 per 100,000 inhabitants, which means an average yearly incidence rate of 12.6 per 100,000 [12.28-12.99]. Governorates of the North West and the Western Central regions of the country are the most endemic area with an average annual incidence rates varying between 19.2 and 33.9 per 100,000, which is at least once and half higher than the national level. After 30 years (1977-2005), the average annual incidence rate slightly dropped, from 15 to 12.6 per 100,000, proving that such zoonosis remains a problem of public health in Tunisia. In order, to control in more or less short term this heavy burden disease and public health expenditure, the only efficient way is the prevention of the diseases with a mass treatment campaign of dogs, principal host of the parasite.  相似文献   
56.
The Glucose-6-phosphate dehydrogenase (G6PI) deficiency is the most common enzymopathy worldwide. WHO had classified Tunisia among countries that are moderately affected by this affection. However, no mass-screening reflecting the real incidence was realized. The aim of this study is to determine the prevalence of this enzymopathy and its molecular basis in Tunisia. A total of 1102 neonates, born in CMNT center of Maternity and of Neonatology of Tunis during the going periods from April, 2005 till May, 2005 and from June, 2006 till September, 2006, have been enclosed in the study. The samplings included 953peripheral venous blood and 149 blood cordon. Among 1102 samplings, only 976 were of use to the screening. In our mass-screening, we consider all newborns that were born in the CMNT during the period of study and were included in the screening. A dosage of the enzymatic activity was realized using spectrophotometric method. G6PD electrophoresis and molecular study by PCR/RFLP were realized for the overdrawn newborn children. Among 976 screening neonates, 43 individuals (4.4%) were found to be G6PD deficient by quantitative enzyme assay. Newborn affected were distributed in 23 boys and 20 girls (sex ratio of 1.15). The electrophoretic mobility and the molecular biology were realized for the affected newborn. Molecular characterization of 30 G6PD deficient neonates revealed that the G6PD A- was the most common and was detected in 20 of 43 individuals (66.7%), followed by G6PD Mediterranean that was detected in 6 (13.3%). At least, 4 other unknown mutations were not able to be determined by PCR/RFLP (n=4). In conclusion G6PD deficiency is frequent in our country, justifying a systematic neonatal screening, to avoid the arisen of grave consequences of this affection. The African variant is the most frequent in our country followed by the Mediterranean one.  相似文献   
57.
Background: Helicobacter pylori (H. pylori) is a major cause of chronic gastritis. Statins have several pleotropic effects and their mechanisms of action could be related to anti‐inflammatory, antioxidants, and immunomodulatory effects. Aim: To determine whether statin therapy affects the severity of chronic gastritis. Materials and Methods: In a retrospective study, we evaluated 516 patients who underwent upper endoscopy. One‐hundred and ninety‐eight patients had chronic gastritis, The 198 patients with chronic gastritis were divided into two groups: group 1 comprised patients with a history of statin therapy and group 2 comprised patients with no history of statin therapy. Both groups were compared for age, gender, body mass index (BMI), underlying diseases, drug therapy, alcohol consumption, smoking and the serum levels of C‐reactive protein (CRP). The presence of H. pylori was determined by gastric biopsy and rapid urease test. The grade and severity of gastritis were assessed using the updated Sydney classification system in two gastric biopsy specimens that were taken from each participant in each group. Results: Of the 198 patients with chronic gastritis, 49% of the patients had mild gastritis and 51% had moderate to severe gastritis. From the results of a multiple logistic regression analysis after adjusting for confounding variables that included age, gender, and BMI, we found that elevated serum CRP levels (odds ratio (OR) 2.33; 95% confidence interval (CI) = 0.8–2.6, p = .02), H. pylori (OR 1.99; CI 0.14–2.4, p = .04), and the use of statin (OR 1.64; CI = 0.71–1.77, p = .05) independently predict the severity of chronic gastritis. Conclusion: Long‐standing statin therapy may reduce the severity of chronic gastritis. Mild increased CRP levels in absence of obvious source can predict the severity of chronic gastritis. Further researches are needed to assess the effect of statin in chronic gastritis.  相似文献   
58.
In order to identify the phlebotomine sandfly populations in Tunisian leishmaniosis foci, an entomological survey was carried out through three entomological seasons (2002-2003-2004) in 19 visceral and cutaneous leishmaniosis areas, located in six bioclimatic zones. Sandfly collections were based on light and sticky traps placed around human leishmaniosis cases. 8,722 phlebotomine sandflies belonging to 12 species were collected. The dominance of subgenus Larroussius species in northern foci, Phlebotomus papatasi in south-western foci and their co-dominance in the centre of the country is in accordance with the distribution of Leishmania infantum and L. major in Tunisia. The low density found in the historical zoonotic cutaneous leishmaniosis focus of Metlaoui in the south-west may indicate the high competence of the local populations. Studied phlebotomine settlements have showed a low specific diversity in most of the studied sites. In L. infantum areas, the dominant species were respectively: P. perfiliewi in the cutaneous leishmaniosis site of the humid bioclimatic stage, P. perniciosus in the cutaneous and visceral leishmaniosis foci of semi-arid and arid bioclimatic stages and P. longicuspis in the visceral leishmaniosis focus of saharan bioclimate. In the zoonotic cutaneous leishmaniosis foci, P. papatasi was a dominant species. In the well-known south-eastern foci of cutaneous leishmaniosis due to L. killicki, P. sergenti was a dominant species with P. perniciosus. In the central emerging foci of L. killicki, P. perniciosus was a dominant species in some sites whereas it was very rare in others. In these sites, the subgenus Paraphlebotomus was always present with a higher abundance of P. alexandri than P. sergenti.  相似文献   
59.
The aerial parts of Centaurea grisebachii ssp. grisebachii, a Greek endemic species belonging to section Acrolophus (Cass.) DC., were investigated for the occurrence of sesquiterpene lactones. The eudesmanolide, 4-epi-malacitenolide was the major compound. In addition to the sesquiterpene lactones, five flavonoid aglycons, two lignans, one nor-isoprenoid and one sterol were found.  相似文献   
60.
Hepcidin, a liver‐expressed antimicrobial peptide, has been demonstrated to act as an iron regulatory hormone as well as to exert a wide spectrum of antimicrobial activity. The aim of this work was the expression, as secreted peptide, purification, and characterization of a new recombinant polyHis‐tagged camel hepcidin (HepcD‐His) in yeast Pichia pastoris . The use of this eukaryotic expression system, for the production of HepcD‐His, having 6 histidine residues at its C terminus, was simpler and more efficient compared with the use of the prokaryotic system Escherichia  coli . Indeed, a single purification step was required to isolate the soluble hepcidin with purity estimated more that 94% and a yield of 2.8 against 0.2 mg/L for the E coli system. Matrix‐assisted laser desorption/ionization time‐of‐flight (TOF)/TOF mass spectrometry of the purified HepcD‐His showed 2 major peaks at m /z 4524.64 and 4634.56 corresponding to camel hepcidin with 39 and 40 amino acids. Evaluation of disulfide bond connectivity with the Ellman method showed an absence of free thiol groups, testifying that the 8 cysteine residues in the peptide are displayed, forming 4 disulfide bridges. Circular dichroism spectroscopy showed that camel hepcidin structure was significantly modified at high temperature of 90°C and returns to its original structure when incubation temperature drops back to 20°C. Interestingly, this peptide showed also a greater bactericidal activity, at low concentration of 9.5μM, against E coli , than the synthetic analog DH3. Thus, the production, at a large scale, of the recombinant camel hepcidin, HepcD‐His, may be helpful for future therapeutic applications including bacterial infection diseases.  相似文献   
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