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141.
Pankaj Sharma Veena Mittal Mala Chhabra Roop Kumari Priyanka Singh Dipesh Bhattacharya Srinivas Venkatesh Arvind Rai 《中国病毒学》2015,30(6):464-469
<正>Dear Editor,Dengue infection is one of the emerging concerns for public health on a global scale.Over the past few years,dengue transmission has increased in the Americas,the western Pacific and southeast Asia.The magnitude,distribution,and clinical severity of dengue outbreaks have been an alarming signal in the southeast Asia region.Major outbreaks have been reported in countries in this 相似文献
142.
143.
Pierre Zalagile Akilimali Espérance Kashala-Abotnes Patou Masika Musumari Patrick Kalambayi Kayembe Thorkild Tylleskar Mala Ali Mapatano 《PloS one》2015,10(10)
Background
Anaemia is associated with adverse outcomes including early death in the first year of antiretroviral therapy (ART). This study reports on the factors associated with persistent anaemia among HIV-infected patients initiating ART in the Democratic Republic of Congo (DR Congo).Methods
We conducted a retrospective cohort study and analyzed data from patients receiving HIV care between January 2004 and December 2012 at two major hospitals in Goma, DR Congo. Haemoglobin concentrations of all patients on ART regimen were obtained prior to and within one year of ART initiation. A logistic regression model was used to identify the predictors of persistent anaemia after 12 months of ART.Results
Of 756 patients, 69% of patients were anaemic (IC95%: 65.7–72.3) at baseline. After 12 months of follow up, there was a 1.2 g/dl average increase of haemoglobin concentration (P < 0.001) with differences depending on the therapeutic regimen. Patients who received zidovudine (AZT) gained less than those who did not receive AZT (0.99 g/dl vs 1.33 g/dl; p< 0.001). Among 445 patient who had anaemia at the beginning, 33% (147/445) had the condition resolved. Among patients with anaemia at ART initiation, those who did not receive cotrimoxazole prophylaxis before starting ART(AOR 3.89; 95% CI 2.09–7.25; P < 0.001) and a AZT initial regimen (AOR 2.19; 95% CI 1.36–3.52; P < 0.001) were significantly at risk of persistent anaemia.Conclusions
More than two thirds of patients had anaemia at baseline. The AZT-containing regimen and absence of cotrimoxazole prophylaxis before starting ART were associated with persistent anaemia 12 months, after initiation of treatment. Considering the large proportion of patients with persistence of anaemia at 12 months, we suggest that it is necessary to conduct a large study to assess anaemia among HIV-infected patients in Goma. 相似文献144.
Z S Khlystova V V Mala?tsev I M Bogdanova E L Rabotnikova 《Biulleten' eksperimental'no? biologii i meditsiny》1985,100(12):727-729
Natural cytotoxic activity of cells from human fetal spleen, liver, bone marrow, appendix, tonsilar glands and thymus was investigated in 14-26-week-old embryos. The spleen and liver expressed powerful NK activity against K-562 target cells from a 22 week-old embryo. Thymocytes and cells from the appendix and tonsilar glands displayed but negligible cytotoxic activity. 相似文献
145.
The present article reports a low molecular weight aspartic protease inhibitor from a Streptomyces sp. MBR04 exhibiting a two-step inhibition mechanism against pepsin. The kinetic interactions revealed a reversible, competitive, slow-tight binding inhibition with an IC(50) and K(i) values of 4.5 nM and 4 nM respectively. The conformational changes induced upon inhibitor binding to pepsin was monitored by far and near UV analysis, demonstrated that the inhibitor binds to the active site and causes inactivation. Chemical modification of the inhibitor with WRK and TNBS abolished the antiproteolytic activity of the inhibitor. 相似文献
146.
Sophie Jegouic Marie-Line Joffret Claire Blanchard Franck B. Riquet Céline Perret Isabelle Pelletier Florence Colbere-Garapin Mala Rakoto-Andrianarivelo Francis Delpeyroux 《PLoS pathogens》2009,5(5)
Ten outbreaks of poliomyelitis caused by pathogenic circulating vaccine-derived polioviruses (cVDPVs) have recently been reported in different regions of the world. Two of these outbreaks occurred in Madagascar. Most cVDPVs were recombinants of mutated poliovaccine strains and other unidentified enteroviruses of species C. We previously reported that a type 2 cVDPV isolated during an outbreak in Madagascar was co-circulating with coxsackieviruses A17 (CA17) and that sequences in the 3′ half of the cVDPV and CA17 genomes were related. The goal of this study was to investigate whether these CA17 isolates can act as recombination partners of poliovirus and subsequently to evaluate the major effects of recombination events on the phenotype of the recombinants. We first cloned the infectious cDNA of a Madagascar CA17 isolate. We then generated recombinant constructs combining the genetic material of this CA17 isolate with that of the type 2 vaccine strain and that of the type 2 cVDPV. Our results showed that poliovirus/CA17 recombinants are viable. The recombinant in which the 3′ half of the vaccine strain genome had been replaced by that of the CA17 genome yielded larger plaques and was less temperature sensitive than its parental strains. The virus in which the 3′ portion of the cVDPV genome was replaced by the 3′ half of the CA17 genome was almost as neurovirulent as the cVDPV in transgenic mice expressing the poliovirus cellular receptor gene. The co-circulation in children and genetic recombination of viruses, differing in their pathogenicity for humans and in certain other biological properties such as receptor usage, can lead to the generation of pathogenic recombinants, thus constituting an interesting model of viral evolution and emergence. 相似文献
147.
Heat shock proteins (HSPs) are upregulated in response to stress and play a protective function in refolding of cellular proteins.
In hypertension, the heart is a vital organ that requires examination and investigation, and primary induction of HSPs is
predominantly effected. Hypertension results from osmotic imbalance during renin-angiotensin cycle inefficiency. Osmotic stress
protein 94 (OSP94) is a stress protein induced upon osmotic imbalance. It is therefore necessary to analyze its precise role
in the hypertensive heart. We have first reported the cloning and expression of human heart OSP94 followed by an analysis
of gene sequence and protein homology. Directional cloning of OSP94 by PCR amplification yielded a 2.5 kb amplicon and was
cloned into pET-15b. Site-directed mutagenesis was essentially followed. mRNA expression levels were evaluated in correlation
with HSPs. Gene analysis indicated a 2520 bp sequence with an 838-amino acid protein complement. Protein homology revealed
highly conserved sequence similarity among mammalian sequences. Structural predictions of OSP94 protein were also investigated.
OSP94 is therefore recognized as a significant stress protein for investigations in hypertensive heart tissues and is a highly
conserved protein in the HSP110 subfamily.
Sequences deposited: EF 197155, NCBI GenBank Accession No. for OSP94 gene sequence; ABM 69040, NCBI GenPept Accession No.
for OSP94 protein sequence. 相似文献
148.
149.
A new, relatively simple method for determining the kinematic properties of jellyfish is presented. The bell movement of the
scyphomedusa (Aurelia sp.) during its pulsation cycle was analysed using computer-aided visualization. Sequences of video images of individual
Aurelia in a large aquarium were taken using a standard video camera. The images were then processed to obtain time series of the
relative positions of selected points on the surface of the medusa’s bell. The duration of the bell relaxation was longer
than that of the bell contraction, thereby confirming published results. In addition, the area of the exumbrellar surface
of Aurelia increased during bell relaxation by more than 1.3-times that of the exumbrellar surface area during the maximum contraction
of the bell. The volume change during the bell pulsation cycle was also measured using the same visualization method. Significant
changes, of up to 50%, in the subumbrellar cavity volume were revealed while, in contrast, the volume between the exumbrellar
and subumbrellar surfaces generally remained unchanged during the entire pulsation cycle of the bell. Comparison of the time
series of the exumbrellar surface area and of the subumbrellar cavity volume indicated that the change of volume takes place
before the change of the surface area of the bell.
Guest editors: K. A. Pitt & J. E. Purcell
Jellyfish Blooms: Causes, Consequences, and Recent Advances 相似文献
150.
Alkaline protease production by a newly isolated Bacillus species from laundry soil was studied for detergent biocompatibility. From its morphological and nucleotide sequence (about
1.5 kb) of its 16S rDNA it was identified as Bacillus species with similarity to Bacillus species Y (Gen Bank entry: ABO 55095), and close homology with Bacillus cohnii YN-2000 (Gen Bank entry: ABO23412). Partial purification of the enzyme by ammonium sulfate (50–70% saturation) yielded 8-fold
purity. Casein zymography and Sodium dodecylsulphate-Polyacrylamide gel electrophoresis (SDS-PAGE) of the partially purified
enzyme revealed two isozymes of molecular sizes approximately 66 kDa and 18 kDa, respectively. The enzyme was most active
at pH 12 and 50°C. At pH 12 the enzyme was stable for 5 h and retained 60% activity. The enzyme retained 44% activity at 50°C
up to 2 h. The protease showed good hydrolysis specificity with different substrates tested. The presence of Mn2+, Co2+ and ethylenediaminetetracetic acid (EDTA) showed profound increase in protease activity. The protease of Bacillus species Y showed excellent stability and compatibility with three locally available detergents (Kite, Tide and Aerial) up
to 3 h retaining almost 70–80% activity and 10–20% activity at room temperature (30°C) and 50°C, respectively, indicating
the potential role of this enzyme for detergent application. 相似文献