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451.
Harma Ellens Eric Mayhew Youcef M. Rustum 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,714(3):479-485
The effect of various doses of different types (reverse phase evaporation vesicles and small unilamellar vesicles) of intravenously injected liposomes on reticuloendothelial activity, as measured by the blood clearance rate of intravenously injected carbon, was investigated. Also the effect of pretreatment with reverse phase evaporation vesicles on blood clearance and tissue distribution of a second dose of similar vesicles was determined. For all concentrations used reverse phase evaporation vesicles caused reduction in reticuloendothelial activity at least up to 4 h after injection. 24 h after administration the rate of carbon clearance returned to the control level. On the contrary small unilamellar vesicles did not block reticuloendothelial activity. Pretreatment with reverse phase evaporation vesicles (250 μmol/kg) caused an increased blood level and a decreased hepatic uptake of a second dose of the vesicles, injected 1 h after the first dose. This seems to be due to a depression of reticuloendothelial activity and not to a depletion of opsonins. Pretreatment with small unilamellar vesicles (250 μmol/kg) had no significant influence on the tissue distribution of a second dose of vesicles. Our results clearly indicate that reverse phase evaporation vesicles cause a reversible depression of reticuloendothelial activity and this depression seems to be induced by a saturation of reticuloendothelial cells with liposomes. 相似文献
452.
453.
A study of nephron function in normal tropical residents using the creatinine and lithium clearances
S. K. Arthur A. K. Nyarko J. Y. Asaku A. Y. Akyeampong 《International journal of biometeorology》1997,41(1):40-43
The kidney bears the brunt of the demands of a tropical climate for water and electrolyte homeostasis. We hypothesised that
a tropical climate may cause adaptive changes in the entire organism leading to altered renal function in our subjects. Hence
renal function data for residents of a temperate climate may not be applic- able to tropical residents. We therefore sought
to elucidate renal function in subjects residing in a tropical climate. We used lithium clearance, C
Li, a non-invasive tool for assessing proximal tubular function in humans, and endogenous creatinine clearance, C
Cr, to estimate proximal tubular function and glomerular function, respectively, in our subjects. We did this in order to establish
whether or not nephron function in our subjects differs from that for residents of a temperate climate. Nineteen male and
12 female Ghanaian subjects aged between 15 and 48 years were studied. The estimated G
Cr
was 117.3±6.6 ml/min for male subjects and 97±6.4 ml/min for female subjects. C
Li was 20.3±1.6 ml/min for male and 19.1±0.4 ml/min for female subjects, respectively. The estimated absolute reabsorption rate
of fluid of proximal tubules was 97.0±6.0 ml/min for males and 78.1±6.0 ml/min for females. The percentage proximal fluid
reabsorption for male and female subjects was 81.2±1.4 and 79.5±1.6, respectively. The differences between male and female
values (mean±SEM) were not statistically significant. The data suggest that the proximal tubule in residents of a tropical
climate may reabsorb more fluid compared to that in residents of a temperate climate. Our values for proximal tubular reabsorption
are higher than those reported for residents of a temperature climate. Our estimate of glomerular filtration, however, is
similar to published data for Caucasians. The difference in proximal tubular function may reflect possible renal adaptation
to a hot, humid climate. We conclude that renal function of tropical residents differs from that of residents of a temperate
climate. This difference may be due to renal adaptation to the hot, tropical climate.
Received: 1 July 1996 / Revised: 22 December 1996 / Accepted: 8 January 1997 相似文献
454.
455.
《Journal of liposome research》2013,23(2):158-165
Background:?STEALTH® liposomal CKD-602 (S-CKD602), a camptothecin analog, is eliminated by the reticuloendothelial system (RES), which consists of cells, including monocytes. We evaluated the relationship between monocyte and absolute neutrophil counts (ANCs) in the blood and pharmacokinetic disposition of S-CKD602 and nonliposomal CKD-602 (NL-CKD602) in patients.Methods:?As part of a phase I study of S-CKD602 and phase I and II studies of NL-CKD602, the percent decreases in ANC and monocytes at their nadir were calculated. After S-CKD602, the amount of CKD-602 recovered in urine was measured.Results:?For S-CKD602 in patients <60 years, the percent decrease in ANC and monocytes were 43?±?31 and 58?±?26%, respectively (P?=?0.001). For S-CKD602 in patients ≥60, the percent decrease in ANC and monocytes were 41?±?31 and 45?±?36%, respectively (P?=?0.50). For NL-CKD602 (n?=?42), the percent decrease in ANC and monocytes were similar (P?>?0.05). For S-CKD602, the relationship between the percent decrease in monocytes and CKD-602 recovered in urine was stronger in patients <60 (R2?=?0.82), compared with patients ≥60 (R2?=?0.30).Conclusions:?Monocytes are more sensitive to S-CKD602, compared with neutrophils, and the increased sensitivity is related to the liposomal formulation, not CKD-602. These results suggest that monocytes engulf S-CKD602, which causes the release of CKD-602 from the liposome and toxicity to the monocytes, and that the effects are more prominent in patients <60. 相似文献
456.
Staphylococcus aureus virulence attenuation and immune clearance mediated by a phage lysin‐derived protein
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Hang Yang Jingjing Xu Wuyou Li Shujuan Wang Junhua Li Junping Yu Yuhong Li Hongping Wei 《The EMBO journal》2018,37(17)
New anti‐infective approaches are much needed to control multi‐drug‐resistant (MDR) pathogens, such as methicillin‐resistant Staphylococcus aureus (MRSA). Here, we found for the first time that a recombinant protein derived from the cell wall binding domain (CBD) of the bacteriophage lysin PlyV12, designated as V12CBD, could attenuate S. aureus virulence and enhance host immune defenses via multiple manners. After binding with V12CBD, S. aureus became less invasive to epithelial cells and more susceptible to macrophage killing. The expressions of multiple important virulence genes of S. aureus were reduced 2.4‐ to 23.4‐fold as response to V12CBD. More significantly, V12CBD could activate macrophages through NF‐κB pathway and enhance phagocytosis against S. aureus. As a result, good protections of the mice from MRSA infections were achieved in therapeutic and prophylactic models. These unique functions of V12CBD would render it a novel alternative molecule to control MDRS. aureus infections. 相似文献
457.
458.
Scott Lute Julie Kozaili Sarah Johnson Kazuya Kobayashi Daniel Strauss 《Biotechnology progress》2020,36(3):e2962
We designed small-scale virus filtration models to investigate the impact of the extended process times and dynamic product streams present in continuous manufacturing. Our data show that the Planova 20N and BioEX virus filters are capable of effectively removing bacteriophage PP7 (>4 log) when run continuously for up to 4 days. Additionally, both Planova 20N and BioEX filters were able to successfully process a mock elution peak of increased protein, salt, and bacteriophage concentrations with only an increase in filtration pressure observed during the higher protein concentration peak. These experiments demonstrated that small-scale viral clearance studies can be designed to model a continuous virus filtration step with specific process parameters. 相似文献
459.
Tim J. C. Anderson Jeff T. Williams Shalini Nair Daniel Sudimack Marion Barends Anchalee Jaidee Ric N. Price Fran?ois Nosten 《Proceedings. Biological sciences / The Royal Society》2010,277(1693):2531-2540
Malaria parasites vary in phenotypic traits of biomedical or biological interest such as growth rate, virulence, sex ratio and drug resistance, and there is considerable interest in identifying the genes that underlie this variation. An important first step is to determine trait heritability (H2). We evaluate two approaches to measuring H2 in natural parasite populations using relatedness inferred from genetic marker data. We collected single-clone Plasmodium falciparum infections from 185 patients from the Thailand–Burma border, monitored parasite clearance following treatment with artemisinin combination therapy (ACT), measured resistance to six antimalarial drugs and genotyped parasites using 335 microsatellites. We found strong relatedness structure. There were 27 groups of two to eight clonally identical (CI) parasites, and 74 per cent of parasites showed significant relatedness to one or more other parasites. Initially, we used matrices of allele sharing and variance components (VC) methods to estimate H2. Inhibitory concentrations (IC50) for six drugs showed significant H2 (0.24 to 0.79, p = 0.06 to 2.85 × 10−9), demonstrating that this study design has adequate power. However, a phenotype of current interest—parasite clearance following ACT—showed no detectable heritability (H2 = 0–0.09, ns) in this population. The existence of CI parasites allows the use of a simple ANOVA approach for quantifying H2, analogous to that used in human twin studies. This gave similar results to the VC method and requires considerably less genotyping information. We conclude (i) that H2 can be effectively measured in malaria parasite populations using minimal genotype data, allowing rational design of genome-wide association studies; and (ii) while drug response (IC50) shows significant H2, parasite clearance following ACT was not heritable in the population studied. 相似文献
460.
《Archives of animal nutrition》2013,67(5):293-301
Abstract This study was conducted to investigate the effect of dietary conjugated linoleic acids (CLA) on growth performance and immune responses in broiler chicks. A total of 240 day-old Arbor Acre male broiler chicks were randomly allotted into four dietary treatments with different inclusion levels of CLA (0, 2.5, 5.0 or 10.0 g/kg) for six weeks. Growth performance, peripheral blood lymphocyte (PBL) proliferation, lysozyme activity, phagocytic activity (carbon clearance) and serum antibody titers against Newcastle disease virus (NDV) vaccine were examined. There were no significant differences in growth performance among treatments (p > 0.05). Chicks fed CLA diets produced more lysozyme activity in serum than the control group at 2 and 6 weeks of age (p < 0.05). Dietary CLA enhanced the PBL proliferation in response to concanavalin A (ConA) at the age of 42 d (p < 0.05). Phagocytic ability was also affected by dietary CLA and chicks fed CLA diets had faster carbon clearance rate (p < 0.05), but antibody titers to NDV was not influenced by dietary CLA. The results of the study suggested that dietary CLA could enhance innate and cellular immune response in broiler chicks, and not affect the growth performance. 相似文献