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941.
Daniela G Morato Florisneide R Barreto José U Braga Marcio S Natividade Maria da Concei??o N Costa Vanessa Morato Maria da Glória Lima Cruz Teixeira 《Memórias do Instituto Oswaldo Cruz》2015,110(4):528-533
Understanding the transmission dynamics of infectious diseases is important to allow
for improvements of control measures. To investigate the spatiotemporal pattern of an
epidemic dengue occurred at a medium-sized city in the Northeast Region of Brazil in
2009, we conducted an ecological study of the notified dengue cases georeferenced
according to epidemiological week (EW) and home address. Kernel density estimation
and space-time interaction were analysed using the Knox method. The evolution of the
epidemic was analysed using an animated projection technique. The dengue incidence
was 6.918.7/100,000 inhabitants; the peak of the epidemic occurred from 8 February-1
March, EWs 6-9 (828.7/100,000 inhabitants). There were cases throughout the city and
was identified space-time interaction. Three epicenters were responsible for
spreading the disease in an expansion and relocation diffusion pattern. If the health
services could detect in real time the epicenters and apply nimbly control measures,
may possibly reduce the magnitude of dengue epidemics. 相似文献
942.
Mariana Concei??o Souza Tatiana Almeida Padua Natalia Domingos Torres Maria Fernanda de Souza Costa Victor Facchinetti Claudia Regina Brand?o Gomes Marcus Vinícius Nora Souza Maria das Gra?as Henriques 《Memórias do Instituto Oswaldo Cruz》2015,110(4):560-565
A rapid decrease in parasitaemia remains the major goal for new antimalarial drugs
and thus, in vivo models must provide precise results concerning parasitaemia
modulation. Hydroxyethylamine comprise an important group of alkanolamine compounds
that exhibit pharmacological properties as proteases inhibitors that has already been
proposed as a new class of antimalarial drugs. Herein, it was tested the antimalarial
property of new nine different hydroxyethylamine derivatives using the green
fluorescent protein (GFP)-expressing Plasmodium berghei strain. By
comparing flow cytometry and microscopic analysis to evaluate parasitaemia
recrudescence, it was observed that flow cytometry was a more sensitive methodology.
The nine hydroxyethylamine derivatives were obtained by inserting one of the
following radical in the para position: H, 4Cl, 4-Br, 4-F, 4-CH3,
4-OCH3, 4-NO2, 4-NH2 and 3-Br. The antimalarial test showed that the compound that
received the methyl group (4-CH3) inhibited 70% of parasite growth. Our results
suggest that GFP-transfected P. berghei is a useful tool to study the recrudescence
of novel antimalarial drugs through parasitaemia examination by flow cytometry.
Furthermore, it was demonstrated that the insertion of a methyl group at the
para position of the sulfonamide ring appears to be critical for
the antimalarial activity of this class of compounds. 相似文献
943.
Daniela Ceccarelli Arlene Chen Nur A. Hasan Shah M. Rashed Anwar Huq Rita R. Colwell 《Applied and environmental microbiology》2015,81(6):1909-1918
Non-O1/non-O139 Vibrio cholerae inhabits estuarine and coastal waters globally, but its clinical significance has not been sufficiently investigated, despite the fact that it has been associated with septicemia and gastroenteritis. The emergence of virulent non-O1/non-O139 V. cholerae is consistent with the recognition of new pathogenic variants worldwide. Oyster, sediment, and water samples were collected during a vibrio surveillance program carried out from 2009 to 2012 in the Chesapeake Bay, Maryland. V. cholerae O1 was detected by a direct fluorescent-antibody (DFA) assay but was not successfully cultured, whereas 395 isolates of non-O1/non-O139 V. cholerae were confirmed by multiplex PCR and serology. Only a few of the non-O1/non-O139 V. cholerae isolates were resistant to ampicillin and/or penicillin. Most of the isolates were sensitive to all antibiotics tested, and 77 to 90% carried the El Tor variant hemolysin gene hlyAET, the actin cross-linking repeats in toxin gene rtxA, the hemagglutinin protease gene hap, and the type 6 secretion system. About 19 to 21% of the isolates carried the neuraminidase-encoding gene nanH and/or the heat-stable toxin (NAG-ST), and only 5% contained a type 3 secretion system. None of the non-O1/non-O139 V. cholerae isolates contained Vibrio pathogenicity island-associated genes. However, ctxA, ace, or zot was present in nine isolates. Fifty-five different genotypes showed up to 12 virulence factors, independent of the source of isolation, and represent the first report of both antibiotic susceptibility and virulence associated with non-O1/non-O139 V. cholerae from the Chesapeake Bay. Since these results confirm the presence of potentially pathogenic non-O1/non-O139 V. cholerae, monitoring for total V. cholerae, regardless of serotype, should be done within the context of public health. 相似文献
944.
Marek??ywicki Joanna?Gracz Wojciech?Kar?owski Tomasz?Twardowski Agata?TyczewskaEmail author 《Acta Physiologiae Plantarum》2015,37(12):265
Glyphosate is a systemic, nonselective and most widely used herbicide in the world. The introduction of glyphosate-resistant crops in the mid-1990s resulted in a dramatic increase in the use of glyphosate herbicide making it most widely used herbicide in the world. The average maize yield loss in the field caused by pests is around 20 % but in many regions it is much higher. It is now clear that glyphosate causes broader range of physiological alterations than previously assumed and some plants gain higher level of resistance to glyphosate without the need to use genetic engineering methods. To understand the mechanisms of such heightened resistance we must first know the processes mediating the plants’ death in response to glyphosate treatment. Here, we show that 12 miRNAs, belonging to miR167, miR396, miR159, miR156, miR169, miR444 and miR827 families, are significantly upregulated, and one, miR166, downregulated following glyphosate treatment. These miRNAs have been previously shown to be involved in abiotic stress responses and implicated in senescence. Strikingly, two of the induced miRNAs, miR444 and miR827, have been shown to regulate phosphate transport pathways, which seem to be common for Pi and glyphosate uptake. 相似文献
945.
Alexandre Bureau Margaret M. Parker Ingo Ruczinski Margaret A. Taub Mary L. Marazita Jeffrey C. Murray Elisabeth Mangold Markus M. Noethen Kirsten U. Ludwig Jacqueline B. Hetmanski Joan E. Bailey-Wilson Cheryl D. Cropp Qing Li Silke Szymczak Hasan Albacha-Hejazi Khalid Alqosayer L. Leigh Field Yah-Huei Wu-Chou Kimberly F. Doheny Hua Ling Alan F. Scott Terri H. Beaty 《Genetics》2014,197(3):1039-1044
A dozen genes/regions have been confirmed as genetic risk factors for oral clefts in human association and linkage studies, and animal models argue even more genes may be involved. Genomic sequencing studies should identify specific causal variants and may reveal additional genes as influencing risk to oral clefts, which have a complex and heterogeneous etiology. We conducted a whole exome sequencing (WES) study to search for potentially causal variants using affected relatives drawn from multiplex cleft families. Two or three affected second, third, and higher degree relatives from 55 multiplex families were sequenced. We examined rare single nucleotide variants (SNVs) shared by affected relatives in 348 recognized candidate genes. Exact probabilities that affected relatives would share these rare variants were calculated, given pedigree structures, and corrected for the number of variants tested. Five novel and potentially damaging SNVs shared by affected distant relatives were found and confirmed by Sanger sequencing. One damaging SNV in CDH1, shared by three affected second cousins from a single family, attained statistical significance (P = 0.02 after correcting for multiple tests). Family-based designs such as the one used in this WES study offer important advantages for identifying genes likely to be causing complex and heterogeneous disorders. 相似文献
946.
Mehmet Bozkurt Ataman Hasan Hüseyin Dönmez Nurcan Dönmez Emrah Sur Mustafa Numan Bucak Kenan Çoyan 《Theriogenology》2014
The aim of this study was to determine the effect of aflatoxin (AF) on spermatologic, biochemical, and testis parameters in rams, and the protective efficiency of esterified glucomannan (EG) co-administered with AF. Thirty-two Merino rams (12–14 months old) were used. The experimental design consisted of four dietary treatments. The control group was fed commercial feed. The AF group was fed with commercial feed plus 250 μg/d of total AF. The EG group received commercial feed plus 2 g/d of EG. The AF + EG group was given commercial feed plus 250 μg/d of total AF and 2 g/d of EG. There were treatment, time, and treatment-by-time interaction effects on sperm motility, abnormal spermatozoa, damaged acrosome, and dead spermatozoa (P < 0.01). The percentage of motile sperm was lower and the percentages of abnormal sperm, sperm with damaged acrosomes, and dead sperm were greater in the AF group than in the control, AF+EG, and EG groups, as from week 3 until the end of week 12 (P < 0.05). As from week 3, hyaluronidase activity in the seminal plasma increased significantly in the AF group, compared with the control. The co-administration of AF+EG was found to be effective in preventing the increase in hyaluronidase activity. As week 4, malondialdehyde (MDA) levels were significantly higher in the AF group compared with the control. The combined administration of AF+EG was found to be effective in lowering the MDA levels, increased by AF, to the levels measured in the control (P < 0.05). Although glutathione (GSH) levels were determined to have significantly decreased in the AF group in comparison to the control, it was observed that, in the group co-administered with AF and EG, particularly after week 7, the GSH levels, which had decreased owing to AF, were largely ameliorated (P < 0.05). In conclusion, AF adversely affected spermatologic, biochemical, and testis parameters, and the combined administration of EG with AF reversibly eliminated these adverse effects in rams. 相似文献
947.
The present study on carp Catla catla is the first attempt to search for a relationship between the concentrations of melatonin, oxidative status, and oocyte dynamics in the ovary of any fish. We measured the levels of melatonin, different antioxidative agents, and the marker of intracellular stress along with the profiles of different developmental stages of oocyte in the ovary of adult carp during four distinct phases in an annual reproductive cycle. Ovarian melatonin titers displayed significant seasonal variations with a peak during spawning and nadir during post-spawning, and thereby underlined its proximity to the course of ovarian development. A significant positive correlation was found between the ovarian levels of melatonin and the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione transferase (GST), although each of them showed a negative correlation with the level of malondialdehyde (MDA)—a faithful indicator of intracellular stress. However, ovarian melatonin titers did not exhibit any correlation with the levels of reduced glutathione (GSH) and the activity of glutathione peroxidase (GPx). Collectively, our findings suggest that melatonin measured in carp ovary may be associated with an enhanced activity/level of selective antioxidative agents for reduction in oxidative stress to augment ovarian functions during the spawning. 相似文献
948.
M. Umer Farooq Awan Murtaza Hasan Javed Iqbal Runhong Lei Wang Fu Lee Ma Hong Hong Qing Yulin Deng 《Molecular biology reports》2014,41(9):5729-5734
Reactive oxygen species (ROS) are produced due to oxidative stress which has wide range of affiliation with different diseases including cancer, heart failure, diabetes and neurodegenerative diseases like Alzheimer’s disease, Parkinson’s disease, ischemic and hemorrhagic diseases. This study shows the involvement of BNIP3 in the amplification of metabolic pathways related to cellular quality control and cellular self defence mechanism in the form of autophagy. We used conventional methods to induce autophagy by treating the cells with H2O2. MTT assay was performed to observe the cellular viability in stressed condition. MDC staining was carried out for detection of autophagosomes formation which confirmed the autophagy. Furthermore, expression of BNIP3 was validated by western blot analysis with LC3 antibody. From these results it is clear that BNIP3 plays a key role in defence mechanism by removing the misfolded proteins through autophagy. These results enhance the practical application of BNIP3 in neuroblastoma cells and are helpful in reducing the chances of neurodegenerative diseases. Although, the exact mode of action is still unknown but these findings unveil a molecular mechanism for the role of autophagy in cell death and provide insight into complex relationship between ROS and non-apoptotic programmed cell death. 相似文献
949.
Hasan Caglar Ugur Mehmet Taspinar Seda Ilgaz Fatma Sert Hande Canpinar Juan A. Rey Javier S. Castresana Asuman Sunguroglu 《Molecular biology reports》2014,41(2):697-703
The treatment of anaplastic astrocytoma (AA) is controversial. New chemotherapeutic approaches are needed for AA treatment. Temozolomide (TMZ) is one of the chemotherapeutic drugs for the treatment of AA. The cytotoxic effects of TMZ can be removed by the MGMT (O(6)-methylguanine-DNA methyltransferase) enzyme. Then, chemotherapeutic resistance to TMZ occurs. MGMT inhibition by MGMT inactivators (such as lomeguatrib) is an important anticancer therapeutic approach to circumvent TMZ resistance. We aim to investigate the effect of TMZ–lomeguatrib combination on MGMT expression and TMZ sensitivity of SW1783 and GOS-3 AA cell lines. The sensitivity of SW1783 and GOS-3 cell lines to TMZ and to the combination of TMZ and lomeguatrib was determined by a cytotoxicity assay. MGMT methylation was detected by MS-PCR. MGMT and p53 expression were investigated by real-time PCR after drug treatment, and the proportion of apoptotic cells was analyzed by flow cytometry. When the combination of TMZ–lomeguatrib (50 μM) was used in AA cell lines, IC50 values were reduced compared to only using TMZ. MGMT expression was decreased, p53 expression was increased, and the proportion of apoptotic cells was induced in both cell lines. The lomeguatrib–TMZ combination did not have any effect on the cell cycle and caused apoptosis by increasing p53 expression and decreasing MGMT expression. Our study is a pilot study investigating a new therapeutic approach for AA treatment, but further research is needed. 相似文献
950.
Anti-inflammatuar and anti-oxidative effects of Nigella sativa L.: 18FDG-PET imaging of inflammation
Emre Entok Mehmet Cengiz Ustuner Cansu Ozbayer Neslihan Tekin Fahrettin Akyuz Berat Yangi Hulyam Kurt Irfan Degirmenci Hasan Veysi Gunes 《Molecular biology reports》2014,41(5):2827-2834
Inflammation has an important role in many diseases such as cystic fibrosis, allergies and cancer. The free radicals produced during inflammation, can induce gene mutations and posttranslational modifications of cancer related proteins. Nigella sativa L. (N. sativa) is herbaceous plant and commonly used as a natural food. It has many pharmacological effects including antibacterial, antifungal, antitumor, analgesic, antipyretic activity. The aim of this study was to investigate the anti-inflammatuar and anti-oxidant activity of N. sativa in acute inflammation. Thus we used the experimental lipopolysaccharides (LPS)-induced model. Intraperitoneal LPS 1 mg/kg was administered to groups. N. sativa (500 mg/kg) and essential oil (5 ml/kg) were given orally to treatment groups, after 24-h of intraperitoneal LPS-injection. To determine the lung inflammation, 18F-fluoro-deoxy-d-glucose (0.8 ml/kg) was administrated under the anesthesia before the 1 h of PET-scanning. After the FDG-PET, samples were collected. Lung and liver 18F-FDG-uptake was calculated. Serum AST, ALT, LDH and hcCRP levels were determined and liver, lung and erythrocyte SOD, MDA and CAT levels were measured. Liver and lung NO and DNA fragmentation levels were determined. MDA levels were decreased in treated inflammation groups whereas increased in untreated inflammation group. SOD and CAT activities in untreated inflammation group were significantly lower. According to the control group, increased AST and ALT levels were found in untreated inflammation group. 18F-FDG uptake of inflammation groups were increased when compare the control group. We found increased 18F-FDG uptake, DNA fragmentation and NO levels in LPS-induced inflammation groups. We conclude that, in LPS-induced inflammation, N. sativa have therapeutic and anti-oxidant effects. 相似文献