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21.
The isolation and structural elucidation of a new naphthylisoquinoline alkaloid, 8-O-methyldioncophyllinol B, from Triphyophyllum peltatum (Hutch. et Dalz.) Airy Shaw (Dioncophyllaceae) is described, together with the revised structures of other 'B-type' compounds previously misidentified as dioncophylline D, dioncophyllinol D, and 8-O-methyldioncophylline D. All of the presently described structures are 7,6'-coupled and thus have to be addressed as 'B-type' naphthylisoquinoline alkaloids. This is in contrast to the initially defined 'D-type' structures, which are 7,8'-coupled as confirmed by a total synthesis of dioncophylline D. Some of these natural and synthetic naphthylisoquinolines were found to display good in vitro antiplasmodial activities.  相似文献   
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Human brucellosis has reemerged as a serious public health threat to the Bedouin population of southern Israel in recent years. Little is known about its economic implications derived from elevated healthcare utilization (HCU). Our objective was to estimate the HCU costs associated with human brucellosis from the insurer perspective. A case-control retrospective study was conducted among Clalit Health Services (CHS) enrollees. Brucellosis cases were defined as individuals that were diagnosed with brucellosis at the Clinical Microbiology Laboratory of Soroka University Medical Center in the 2010–2012 period (n = 470). Control subjects were randomly selected and matched 1:3 by age, sex, clinic, and primary physician (n = 1,410). HCU data, demographic characteristics and comorbidities were obtained from CHS computerized database. Mean±SD age of the brucellosis cases was 26.6±17.6 years. 63% were male and 85% were Bedouins. No significant difference in Charlson comorbidity index was found between brucellosis cases and controls (0.41 vs. 0.45, respectively, P = 0.391). Before diagnosis (baseline), the average total annual HCU cost of brucellosis cases was slightly yet significantly higher than that of the control group ($439 vs. $382, P<0.05), however, no significant differences were found at baseline in the predominant components of HCU, i.e. hospitalizations, diagnostic procedures, and medications. At the year following diagnosis, the average total annual HCU costs of brucellosis cases was significantly higher than that of controls ($1,327 vs. $380, respectively, P<0.001). Most of the difference stems from 7.9 times higher hospitalization costs (p<0.001). Additional elevated costs were 3.6 times higher laboratory tests (P<0.001), 2.8 times higher emergency room visits (P<0.001), 1.8 times higher medication (P<0.001) and 1.3 times higher diagnostic procedures (P<0.001). We conclude that human brucellosis is associated with elevated HCU costs. Considering these results in cost-effective analyses may be crucial for both reducing health inequities and optimal allocation of health systems’ scarce resources.  相似文献   
24.

Background

The adhesion of Plasmodium falciparum parasitized red blood cell (PRBC) to human endothelial cells (EC) induces inflammatory processes, coagulation cascades, oxidative stress and apoptosis. These pathological processes are suspected to be responsible for the blood-brain-barrier and other organs' endothelial dysfunctions observed in fatal cases of malaria. Atorvastatin, a drug that belongs to the lowering cholesterol molecule family of statins, has been shown to ameliorate endothelial functions and is widely used in patients with cardiovascular disorders.

Methods

The effect of this compound on PRBC induced endothelial impairments was assessed using endothelial co-culture models.

Results

Atorvastatin pre-treatment of EC was found to reduce the expression of adhesion molecules and P. falciparum cytoadherence, to protect cells against PRBC-induced apoptosis and to enhance endothelial monolayer integrity during co-incubation with parasites.

Conclusions

These results might suggest a potential interest use of atorvastatin as a protective treatment to interfere with the pathophysiological cascades leading to severe malaria.
  相似文献   
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Although the substantial burdens of rotavirus and pneumococcal disease have motivated many countries to consider introducing the rotavirus vaccine (RV) and heptavalent pneumococcal conjugate vaccine (PCV-7) to their National Immunization Programs (EPIs), these new vaccines could affect the countries' vaccine supply chains (i.e., the series of steps required to get a vaccine from their manufacturers to patients). We developed detailed computational models of the Trang Province, Thailand, vaccine supply chain to simulate introducing various RV and PCV-7 vaccine presentations and their combinations. Our results showed that the volumes of these new vaccines in addition to current routine vaccines could meet and even exceed (1) the refrigerator space at the provincial district and sub-district levels and (2) the transport cold space at district and sub-district levels preventing other vaccines from being available to patients who arrive to be immunized. Besides the smallest RV presentation (17.1 cm3/dose), all other vaccine introduction scenarios required added storage capacity at the provincial level (range: 20 L-1151 L per month) for the three largest formulations, and district level (range: 1 L-124 L per month) across all introduction scenarios. Similarly, with the exception of the two smallest RV presentation (17.1 cm3/dose), added transport capacity was required at both district and sub-district levels. Added transport capacity required across introduction scenarios from the provincial to district levels ranged from 1 L-187 L, and district to sub-district levels ranged from 1 L-13 L per shipment. Finally, only the smallest RV vaccine presentation (17.1 cm3/dose) had no appreciable effect on vaccine availability at sub-districts. All other RV and PCV-7 vaccines were too large for the current supply chain to handle without modifications such as increasing storage or transport capacity. Introducing these new vaccines to Thailand could have dynamic effects on the availability of all vaccines that may not be initially apparent to decision-makers.  相似文献   
26.
Background: Endovascular angioplasty and stent placement is currently the most frequent treatment for iliac artery occlusive disease. However, despite a successful endovascular procedure, some patients do not experience symptomatic improvement and satisfaction with their care. This study seeks to identify patient-related factors associated with lack of symptomatic improvement after endovascular iliac artery treatment in male veterans.Methods: Retrospective review of patients treated with endovascular methods for iliac artery occlusive disease between January 2008 and July 2012 at VA Connecticut Healthcare System. Symptomatic improvement on the first post-operative visit was evaluated, with bilateral treatments counted separately.Results: Sixty-two patients had 91 iliac arteries treated with angioplasty and stent placement. Forty-seven (52 percent) legs had critical limb ischemia, and 77 (85 percent) had at least two-vessel distal runoff. Angiographic success was 100 percent. Patient-reported symptomatic improvement at the first post-operative visit was 55 percent (50/91). Lack of symptomatic improvement correlated with older age (OR 1.09 [1.03-1.17], p = 0.008), presence of critical limb ischemia (OR 3.03 [1.09-8.65], p = 0.034), and need for additional surgical intervention (OR 5.61 [1.65-17.36], p = 0.006). Survival, primary and secondary patency, and freedom from restenosis were comparable between patients who reported symptomatic improvement and those who did not.Conclusions: Despite angiographically successful revascularization, patients who are older or have critical limb ischemia who are treated with isolated endovascular iliac artery intervention are more likely to require additional interventions and less likely to experience symptomatic improvement. These patients may need more extensive infra-inguinal revascularization than isolated iliac angioplasty and stent placement, despite a preserved ankle-brachial index. Quality of life needs to be measured with formal instruments after iliac artery endovascular treatment, especially to determine long term outcomes.  相似文献   
27.
Ancistrocladus abbreviatus Airy Shaw (Ancistrocladaceae), a West African liana producing naphthylisoquinoline alkaloids, was successfully raised from seeds in vitro. Clonal propagation was best achieved growing nodal stem segments on 1/5 Linsmaier and Skoog medium with full strength organics and supplemented with 0.02 μM thidiazuron, 4.44 μM 6-benzylaminopurine and 0.05 μM 1-naphthaleneacetic acid. Detached axillary shoots were grown on Anderson's Rhododendron medium devoid of phytohormones and rooted within one month when dipped in 4.92 μM indole-3-butyric acid. Rooted plants became acclimatized to nonsterile greenhouse conditions. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
28.
The efficiency of different FinnishFrankia strains as symbionts onAlnus incana (L.) Moench was evaluated in inoculation experiments by measuring nitrogen fixation and biomass production. Since all available pure cultures ofFrankia are of the Sp type (sporangia not formed in nodules), but the dominant nodule endophyte ofA. incana in Finland is of the Sp+ type (sporangia formed in nodules), crushed nodules of thisFrankia type were included. The Sp pure cultures, whether originating fromA. incana orA. glutinosa, produced with one exception, similar biomass withA. incana. The highest biomass was produced with an American reference strain fromA. viridis crispa. Using Sp+ nodule homogenates fromA. incana as inoculum, the biomass production was only one third of that produced by Sp pure cultures from the same host. Hence, through selection of the endophyte it is possible to exert a considerable influence on the productivity ofAlnus incana.  相似文献   
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Host specificity between local Frankia strains and native alders [Alnus incana (L.) Moench and A. glutinosa (L.) Gaertn.] was evaluated in inoculation experiments. Pure cultures of Frankia , whether originating from A. incana or A. glutinosa , were infective and effective on both host species. These pure cultures were isolated from spore-negative (Sp) nodules. From spore-positive (Sp+) nodules no Frankia isolates were obtained. This strain type resisted all our isolation attempts and therefore crushed nodules had to be used for Sp+ type inoculations.
The Sp+ type Frankia populations differed in their host specificity. Sp+ nodules from A. glutinosa were effective on both alder species, but Sp+ nodules from A. incana induced effective nodules only on the original host; on A. glutinosa only small (1-3mm) prenodule-like structures were found. Such A. glutinosa plants died on N-free medium, thus showing that these nodules were ineffective. In the effective nodules the middle cortex was dominated by infected cells filled with vesicle clusters. In the ineffective nodules only a few cortical cells were infected and sporangia predominated in these cells. Surprisingly enough they also contained vesicle-like structures as demonstrated in electron micrographs.  相似文献   
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