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171.
Tazeen Hasan Jafar Ngiap Chuan Tan Rupesh Madhukar Shirore John Carson Allen Eric Andrew Finkelstein Siew Wai Hwang Agnes Ying Leng Koong Peter Kirm Seng Moey Gary Chun-Yun Kang Chris Wan Teng Goh Reena Chandhini Subramanian Anandan Gerard Thiagarajah Chandrika Ramakrishnan Ching Wee Lim Jianying Liu for SingHypertension Study Group 《PLoS medicine》2022,19(6)
BackgroundDespite availability of clinical practice guidelines for hypertension management, blood pressure (BP) control remains sub-optimal (<30%) even in high-income countries. This study aims to assess the effectiveness of a potentially scalable multicomponent intervention integrated into primary care system compared to usual care on BP control.Methods and findingsA cluster-randomized controlled trial was conducted in 8 government clinics in Singapore. The trial enrolled 916 patients aged ≥40 years with uncontrolled hypertension (systolic BP (SBP) ≥140 mmHg or diastolic BP (DBP) ≥90 mmHg).Multicomponent intervention consisted of physician training in risk-based treatment of hypertension, subsidized losartan-HCTZ single-pill combination (SPC) medications, nurse training in motivational conversations (MCs), and telephone follow-ups. Usual care (controls) comprised of routine care in the clinics, no MC or telephone follow-ups, and no subsidy on SPCs. The primary outcome was mean SBP at 24 months’ post-baseline. Four clinics (447 patients) were randomized to intervention and 4 (469) to usual care. Patient enrolment commenced in January 2017, and follow-up was during December 2018 to September 2020. Analysis used intention-to-treat principles. The primary outcome was SBP at 24 months. BP at baseline, 12 and 24 months was modeled at the patient level in a likelihood-based, linear mixed model repeated measures analysis with treatment group, follow-up, treatment group × follow-up interaction as fixed effects, and random cluster (clinic) effects.A total of 766 (83.6%) patients completed 2-year follow-up. A total of 63 (14.1%) and 87 (18.6%) patients in intervention and in usual care, respectively, were lost to follow-up. At 24 months, the adjusted mean SBP was significantly lower in the intervention group compared to usual care (−3.3 mmHg; 95% CI: −6.34, −0.32; p = 0.03). The intervention led to higher BP control (odds ratio 1.51; 95% CI: 1.10, 2.09; p = 0.01), lower odds of high (>20%) 10-year cardiovascular risk score (OR 0.67; 95% CI: 0.47, 0.97; p = 0.03), and lower mean log albuminuria (−0.22; 95% CI: −0.41, −0.02; p = 0.03). Mean DBP, mortality rates, and serious adverse events including hospitalizations were not different between groups. The main limitation was no masking in the trial.ConclusionsA multicomponent intervention consisting of physicians trained in risk-based treatment, subsidized SPC medications, nurse-delivered motivational conversation, and telephone follow-ups improved BP control and lowered cardiovascular risk. Wide-scale implementation of a multicomponent intervention such as the one in our trial is likely to reduce hypertension-related morbidity and mortality globally.Trial registrationTrial Registration: Clinicaltrials.gov .Tazeen H Jafar and colleagues present findings from a cluster-randomized controlled trial conducted to evaluate the effectiveness of an intervention designed to manage hypertension. NCT02972619相似文献
172.
Characterization and expression of the plasmid-borne bedD gene from Pseudomonas putida ML2, which codes for a NAD+-dependent cis-benzene dihydrodiol dehydrogenase.
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The catabolic plasmid pHMT112 in Pseudomonas putida ML2 contains the bed gene cluster encoding benzene dioxygenase (bedC1C2BA) and a NAD+-dependent dehydrogenase (bedD) required to convert benzene into catechol. Analysis of the nucleotide sequence upstream of the benzene dioxygenase gene cluster (bedC1C2BA) revealed a 1,098-bp open reading frame (bedD) flanked by two 42-bp direct repeats, each containing a 14-bp sequence identical to the inverted repeat of IS26. In vitro translation analysis showed bedD to code for a polypeptide of ca. 39 kDa. Both the nucleotide and the deduced amino acid sequences show significant identity to sequences of glycerol dehydrogenases from Escherichia coli, Citrobacter freundii, and Bacillus stearothermophilus. A bedD mutant of P. putida ML2 in which the gene was disrupted by a kanamycin resistance cassette was unable to utilize benzene for growth. The bedD gene product was found to complement the todD mutation in P. putida 39/D, the latter defective in the analogous cis-toluene dihydrodiol dehydrogenase. The dehydrogenase encoded by bedD) was overexpressed in Escherichia coli and purified. It was found to utilize NAD+ as an electron acceptor and exhibited higher substrate specificity for cis-benzene dihydrodiol and 1,2-propanediol compared with glycerol. Such a medium-chain dehydrogenase is the first to be reported for a Pseudomonas species, and its association with an aromatic ring-hydroxylating dioxygenase is unique among bacterial species capable of metabolizing aromatic hydrocarbons. 相似文献
173.
New approach of monitoring changes in chlorophyll a fluorescence of single guard cells and protoplasts in response to physiological stimuli 总被引:4,自引:0,他引:4
A new type of microfluorometer was applied to assess photosynthesis at the single-cell level by chlorophyll fluorescence using the saturation pulse method. A microscopy–pulse amplitude modulation (PAM) chlorophyll fluorometer was combined with a Zeiss Axiovert 25 inverted epifluorescence microscope for high-resolution measurements on single mesophyll and guard cells and the respective protoplasts. Available information includes effective quantum yield of photosystem II, relative electron transport rate and energization of the thylakoid membrane due to the transthylakoidal proton gradient. Dark–light induction curves of guard cell (GCPs) and mesophyll cell protoplasts (MCPs) displayed very similar characteristics, indicating similar functional organization of thylakoid membranes in both types of chloroplasts. Light response curves, however, revealed much earlier saturation of photosynthetic electron flow in GCPs than in MCPs. Under anaerobiosis, photosynthetic electron flow and membrane energization were severely suppressed. A similar effect was observed in guard cells when epidermal peels were incubated with the fungal toxin fusicoccin which activates the plasma membrane H+-ATPase and causes irreversible opening of stomata. The drop in electron transport rate was prevented by blocking ATP consumption of the H+ pump or by glucose addition. These results show that chlorophyll fluorescence quenching analysis allows profound insights into stomatal physiology. 相似文献
174.
Rice blast, caused by the pathogen Magnaporthe oryzae, is a serious hindrance to rice production and has emerged as an important model for the characterization of molecular mechanisms relevant to pathogenic development in plants. Similar to other pathogenic fungi, conidiation plays a central role in initiation of M.oryzae infection and spread over a large area. However, relatively little is known regarding the molecular mechanisms that underlie conidiation in M. oryzae. To better characterize these mechanisms, we identified a conidiation-defective mutant, ATMT0225B6 (MoCDC15(T-DNA)), in which a T-DNA insertion disrupted a gene that encodes a homolog of fission yeast cdc15, and generated a second strain containing a disruption in the same allele (ΔMoCDC15(T-DNA)). The cdc15 gene has been shown to act as a coordinator of the cell cycle in yeast. Functional analysis of the MoCDC15(T-DNA) and ΔMoCDC15(T-DNA) mutants revealed that MoCDC15 is required for conidiation, preinfection development and pathogenicity in M. oryzae. Conidia from these mutants were viable, but failed to adhere to hydrophobic surface, a crucial step required for subsequent pathogenic development. All phenotypic defects observed in mutants were rescued in a strain complemented with wild type MoCDC15. Together, these data indicate that MoCDC15 functions as a coordinator of several biological processes important for pathogenic development in M. oryzae. 相似文献
175.
176.
Lipid droplets (LDs) were once viewed as simple, inert lipid micelles. However, they are now known to be organelles with a rich proteome involved in a myriad of cellular processes. LDs are heterogeneous in nature with different sizes and compositions of phospholipids, neutral lipids and proteins. This review takes a focused look at the roles of proteins involved in the regulation of LD formation, expansion, and morphology. The related proteins are summarized such as the fat-specific protein (Fsp27), fat storage-inducing trans- membrane (FIT) proteins, seipin and ADP-ribosylation factor 1-coat protein complex I (Arf-COPI). Finally, we present important challenges in LD biology for a deeper understanding of this dynamic organelle to be achieved. 相似文献
177.
Role of fungi in freshwater ecosystems 总被引:7,自引:0,他引:7
Michelle K.M. Wong Teik-Khiang Goh I. John Hodgkiss Kevin D. Hyde V. Mala Ranghoo Clement K.M. Tsui Wai-Hong Ho Wilson S.W. Wong Tsz-Kit Yuen 《Biodiversity and Conservation》1998,7(9):1187-1206
There are more than 600 species of freshwater fungi with a greater number known from temperate, as compared to tropical, regions. Three main groups can be considered which include Ingoldian fungi, aquatic ascomycetes and non-Ingoldian hyphomycetes, chytrids and, oomycetes. The fungi occurring in lentic habitats mostly differ from those occurring in lotic habitats. Although there is no comprehensive work dealing with the biogeography of all groups of freshwater fungi, their distribution probably follows that of Ingoldian fungi, which are either cosmopolitan, restricted to pantemperate or pantropical regions, or in a few cases, have a restricted distribution. Freshwater fungi are thought to have evolved from terrestrial ancestors. Many species are clearly adapted to life in freshwater as their propagules have specialised aquatic dispersal abilities. Freshwater fungi are involved in the decay of wood and leafy material and also cause diseases of plants and animals. These areas are briefly reviewed. Gaps in our knowledge of freshwater fungi are discussed and areas in need of research are suggested. 相似文献
178.
A gas chromatographic method for the separation and quantitation of the 20 protein amino acids is described using N-methyl-N(tert.-butyldimethylsilyl)trifluoroacetamide, with 1% tert.-butyldimethylchlorosilane as catalyst, to prepare the tert.-butyldimethylsilyl amino acid derivatives. Alkylsilylation of amino acids proceeds at 140 degrees C in 20 min. The derivatives formed in the one-step reaction are used directly for gas-liquid chromatographic analysis, using a flame-ionization detector, without prior isolation or purification. Complete separation and quantitation of all protein amino acids are readily achieved using a 15-m DB-5 capillary column. Strict linearity extends from less than 15 to about 100 ng for all amino acids except Arg, which has a linear range from 50 to 300 ng. The limits of detection, however, range from one to several hundred nanograms. The method was used to analyze the free amino acid pool in carnation petals. 相似文献
179.
Enhancement of transient gene expression by fed-batch culture of HEK 293 EBNA1 cells in suspension 总被引:1,自引:0,他引:1
Enhanced green fluorescence protein (GFP) and erythropoietin (EPO) were used as reporters to assess and improve transient
gene expression in HEK 293 EBNA1 cells. The production of EPO only lasted 3 days and reached 18.1 mg/l in suspension cultures
in 1 l batch bioreactors. However, GFP expression examined in well-plate experiments persisted for 12 days in transfected
cells but decreased rapidly within the next 15 days. These results suggest that the retaining of a plasmid in cells may not
be a limiting factor for protein expression in large-scale transient transfection. To improve cell maintenance and protein
expression, a fed-batch culture was performed using an enriched medium, a mixture of equal volumes of 293 SFM II medium and
a 5 × amino acid solution prepared based on DMEM/F12 medium formula. EPO reached 33.6 mg/l, representing 86% increase over
that of the batch culture. Moreover, the total amount of EPO produced was increased by 165% in view of the volume increase
in the fed-batch culture. The serum-free medium used in this work enables cells growing well and transfection without medium
change. Thus, the process reported here is simple and easy to scale up. 相似文献
180.
Bon Marie-Claude Bonal Damien Goh Doreen K. Monteuuis Olivier 《Plant Cell, Tissue and Organ Culture》1998,53(3):171-177
The influence of five different macronutrient formulations and various growth regulators on micropropagation of single node
explants from Acacia mangium and Paraserianthes falcataria seedlings was examined after 4 weeks and 8 weeks in vitro. The
experiment was repeated 4 months later. On media lacking growth regulators, growth and development were significantly influenced
by the different macronutrient solutions tested, although morphogenic responses could vary according to the species. For instance,
P. falcataria displayed a greater ability for adventitious rooting than A. mangium. Overall, Knop macronutrient solution induced
the weakest responses. Explant responsiveness was significantly influenced by the addition of 2.2 or 4.4 μM 6-benzyladenine
combined with either 1.4 or 2.3 μM kinetin, 1.5 or 2.5 μM indolebutyric acid or 1.6 or 2.7 μM naphthaleneacetic acid. The
various combinations of growth regulators tested were shown to inhibit the rooting ability of the explants, while stimulating
the production of basal shoots for both species, and of axillary shoots only for A. mangium. In such experimental conditions,
A. mangium displayed overall a greater potential for micropropagation than P. falcataria.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献