ABSTRACT
BACKGROUND: Salmonella pathogenicity island (SPI)-13 is conserved in many serovars of S. enterica, including S. Enteritidis, S. Typhimurium and S. Gallinarum. However, it is absent in typhoid serovars such as S. Typhi and Paratyphi A, which carry SPI-8 at the same genomic location. Because the interaction with macrophages is a critical step in Salmonella pathogenicity, in this study we investigated the role played by SPI-13 and SPI-8 in the interaction of S. Enteritidis and S. Typhi with cultured murine (RAW264.7) and human (THP-1) macrophages. RESULTS: Our results showed that SPI-13 was required for internalization of S. Enteritidis in murine but not human macrophages. On the other hand, SPI-8 was not required for the interaction of S. Typhi with human or murine macrophages. Of note, the presence of an intact copy of SPI-13 in a S. Typhi mutant carrying a deletion of SPI-8 did not improve its ability to be internalized by, or survive in human or murine macrophages. CONCLUSIONS: Altogether, our results point out to different roles for SPI-13 and SPI-8 during Salmonella infection. While SPI-13 contributes to the interaction of S. Enteritidis with murine macrophages, SPI-8 is not required in the interaction of S. Typhi with murine or human macrophages. We hypothesized that typhoid serovars have lost SPI-13 and maintained SPI-8 to improve their fitness during another phase of human infection.
Subject(s)
Humans , Animals , Mice , Salmonella enteritidis/genetics , Salmonella Infections/microbiology , Salmonella typhi/genetics , Genomic Islands/physiology , Macrophages/microbiology , Species Specificity , Cell Survival , Cells, Cultured , Polymerase Chain Reaction , Analysis of Variance , Genome, Bacterial , Bacterial Physiological Phenomena , Genomic Islands/genetics , Microbial Interactions/genetics , Serogroup , RAW 264.7 Cells , MuridaeABSTRACT
Objective PU.1 plays a key role in innate immune function in the alveolar macrophage.This study was to con-struct and identify recombinant adenovirus vectors carrying the human transcription factor PU.1 gene. Methods The recombinant shut-tle plasmid was obtained from the PU.1 gene ( SPI1) and eukaryotic expression vector that digested by restriction enzymes and connected by T4 DNA ligase.The target fragment SPI1-IRES-EGFP was amplified by PCR.The product was cloned into the intermediate pDONR221 and then recombined with the adenovirus backbone plasmid pAd/CMV/V5-DEST to form a recombinant adenovirus vector. The recombinant adenovirus vector was linearized by PacI and then transfected into human embryonic kidney (HEK293) cells to obtain the recombinant adenovirus pAD-SPI1-IRES-EGFP, which was then propagated in HEK293 cells, filtered and purified to obtain high-con-centration adenoviruses.The adenovirus titer was determined by TCID 50 assay.The PU.1 gene expression in the HEK293 cells was con-firmed by fluorescence microscopy and real-time qPCR. Results PCR amplification, restriction digestion and sequencing analysis showed the recombinant adenovirus carried the correct PU.1 gene.The final virus titer, calculated by TCID 50, was 8 ×1011 IU/mL. Green fluorescence was observed under the fluorescence microscope. Real-time qPCR confirmed that the expression of PU.1 mRNA was increased by 2189.93 folds. Conclusion The recombinant adenovirus vector carrying the PU.1 gene was constructed and obtained successfully, which could contribute to further studies of the influence of PU.1 overex-pression on the innate defense against Aspergillus fumigatus.
ABSTRACT
The anomalies of Sea Surface Temperature (SST) influence rainfall and therefore the regime of the rise and fall in the level of the rivers in the Amazon region. The aim of this study was to investigate the influence of the El Nino-Southern Oscillation (ENSO) on hydroclimatic variables and identify the existence of trends on these variables in the Curuá-Una hydroelectric reservoir in the West of the State of Pará. It was used 27 years of monthly precipitation and water flow data to identify possible trends using a non-parametric test (Mann Kendall, p<0.05), and the standardized precipitation index (SPI) was also calculated. The results indicate a positive tendency of the influence of the ENSO on hydroclimatic variables, although it was observed that the rainfall did not increase over the period of 1977 to 2004. The SPI indicates that extreme events of precipitation are related to El Nino and La Nina and that lower precipitation periods were more intense in the decades of the 80´s and 90's. The results show that El Nino events can directly affect the water balance at the micro-watershed of Curuá-Una, as was observed in 2015.
As anomalias da temperatura da superfície do mar (TSM) influenciam as chuvas e consequentemente o regime de subida e descida do nível dos rios na região amazônica. O objetivo deste estudo foi verificar a influência de eventos El Niño Oscilação Sul (ENSO) sobre algumas variáveis hidroclimáticas e identificar a existência de tendência sobre essas variáveis para o reservatório de Curuá-Una no oeste do Pará. Utilizaram-se 27 anos de dados mensais de precipitação e vazão para identificar possíveis tendências utilizando um teste não paramétrico (Mann Kendall, p<0.05) e calculado o índice de precipitação normalizado (SPI). Os resultados apresentam tendência positiva da influência do ENOS sobre as variáveis hidroclimáticas, embora não foi observado um aumento na precipitação para o período de 1977 a 2004. O índice de precipitação normalizado revela que os eventos extremos de seca e precipitação estão relacionados com eventos de El Niño e La Niña e que os eventos de baixa precipitação foram mais intensos nas décadas de 80 e 90. Os resultados revelam ainda que eventos de El Niño afetam diretamente o balanço hídrico da micro bacia do reservatório de Curuá-Una, como recentemente em 2015.
Subject(s)
Hydroelectric Power Plants (Environmental Health)/analysis , 34613 , 35198 , Rain Measurement , Droughts , Climate ChangeABSTRACT
HilA is a central regulator of Salmonella pathogenicity island 1 (SPI1), which is necessary for host invasion by Salmonella and induction of gastroenteritis. The iagB lies downstream of hilA and is thought to be co-transcribed with hilA, but iagB expression has not yet been analyzed directly. In this study, iagB expression in various mutant strains was measured to determine whether the expression pattern was similar to that of hilA. A β-galactosidase assay revealed that iagB expression was greater under shaking than standing culture condition. iagB expression was decreased in relA/spoT and ihfB mutants but not in luxS mutant, in line with previous reports on hilA expression. The hilA and iagB mRNA levels decreased by approximately 2-fold in arcA mutant grown aerobically and increased by approximately 10-fold in fnr mutant grown anaerobically. Although the fold changes in hilA and iagB mRNA level differed in hfq mutant strain, the patterns of time- and Hfq-dependent regulation were similar for both genes. Thus, iagB and hilA exhibited similar expression patterns in various mutational backgrounds and under different growth condition.
Subject(s)
Gastroenteritis , Genomic Islands , RNA, Messenger , Salmonella typhimurium , Salmonella , VirulenceABSTRACT
Anuradhapura district is one of the largest agricultural crop production areas in Sri Lanka. But it is often affected by droughts and droughts caused severe damage for agricultural industry. Thus it is very important to identify the drought characteristics (drought duration and drought severity) and their joint probability distribution to minimize the adverse effects of droughts. Drought characteristics were defined using 3-month standard precipitation index (SPI). It is calculated using monthly rainfall data from 1951 to 2007 in Anuradhapura. Occurrences of 46 drought events were indentified using the calculated SPI. Since dependency nature of the drought variables, copula based joint distribution was used to calculate the joint distribution. The joint distribution could be obtained by combining the marginal distributions using copula. Five copulas were examined and compared to find the best fitted copula to represent the joint distribution. The best marginal distributions were identified as the gamma distributions for drought durations and drought severity using AIC, BIC and Kolmogorov-Smirnov test. Frank copula was identified as the best copula based on AIC, BIC and Cramer-Von Mises statistics. The joint distribution was derived combining the gamma distributions using the Frank copula. The univariate and joint returns periods of droughts were calculated. A drought event occurred in 1974 was identified as a major drought event. Drought duration and severity in 1974 were 9 months and 10.95 respectively. Using the indentified univariate and multivariate return periods, drought risks could be minimized by preplanning and making decision against adverse effects.
ABSTRACT
Objective To explore feasibility and therapeutic effect of posterior decompression by vertebral body resection, interbody bone fusion and transpedicular screw internal fixation in treatment of severe rotational throracolumar fracture and dislocation. Methods From October 2007 to July 2008, nine patients with severe rotational throracolumar fracture and dislocation classified as AO C types under-went decompression by vertebral boby resection, intervertebral bone fusion and transpedicular screw inter-nal fixation via a posterior midline small incision. There were eight males and one female, at age range from 23 to 54 years. All patients involved levels at T_(11)-L_2. According to AO classification, there were three patients with type C1 bursting fractures with rotational dislocation, five with distraction fracture com-bined with rotational dislocation and one with rotational distraction shear fracture/dislocation. The preop-erative Frankel Grading was Grade A in three patients, Grade B in one, Grade C in four and Grade D in one. Postoperative neurological status, the correction and loss of dislocation and the location and union of bone graft were reviewed. Results All patients received successful operation, with operation time of 3.5-5.8 hours (mean 4.4 hours), blood loss of 1 200-3 500 ml (mean 1 800 ml). The follow- up period in nine patients was 3-12 months (mean seven months). Postoperative X-ray photographs showed that the dislocation in all patients was reduced, the spine curvature was recovered to normal and the intervertebral bone graft was well fixed. Three patients at Frankel Grade A had no improvement, one at Grade B was improved to Grade C. Of four patients at Grade C, three patients were improved to Grade D. The follow-up showed bony fusion in all patients, with no loosening, dislocation or breakage of the internal fixation or implants. Conclusions For severe rotational throracolumar fracture and dislocation, decompression, reduction, fusion and fixation are rather difficult, while sufficient posterior decompression by vertebral body resection, rigid interbody bone fusion and transpadicular screw internal fixation can be an effective alternative measure.
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Objective To design a holter, which can record ECG for long time. Methods SD(secure digital) card was adopted as mass storage medium. The preprocessed ECG signals were converted into digital data which were stored temporarily into SD card by the USB-2.0-spicified microcontroller CY7C68013A. Results SPI bus was introduced for data communication between the host and SD card. The LCD module was utilized to display the menu and states of the system. The data stored in SD card were transmitted to a PC via the USB, or read by a specified card reader.1 GB SD card could record for about one month. Conclusion The portable design of this device is convenient for outgoing.
ABSTRACT
The control system of radiating therapeutic instrument, powerful and reliable, is designed with the new chips of P89LPC669 and MAX669. Its hardware organization, system function and software framework are introduced in this paper.