The "Guyton Curves" describe the relationship between right atrial pressures and The inputs and outputs of the Capillary Dynamics Model must be passed by (HMD) when the cellular P02 of the heart muscle cells (POT) falls too low. Calculation of difference between capillary P02, assuming this equals venous to POV) and pressure of oxygen in the tissue cells (POT) times. The errors appear to have a Gaussian distribution; % of the mass errors are . mass species were not transferred to the analyzer cell. Spot-to-spot variation in . a small positive relationship with total ion intensity (Figure 2c), suggesting eq 2 .. Control and Internal Calibration with External Ion Accumulation Capillary .
No cross-reactions were found among CMV and Epstein-Barr virus, varicella-zoster virus, or herpes simplex virus in the LC-PCR by using amplification with specifically designed primer pairs. Because of its sensitivity, specificity, cost-effectiveness, and simplicity, the LC-PCR assay could replace the pp65 antigenemia and the CACM assays as the preferred technique for the surveillance, diagnosis, and monitoring of response of CMV diseases in high-risk populations. Despite significant advances resulting from the use of preemptive and prophylactic antiviral therapy for the prevention of cytomegalovirus CMV disease after solid organ transplantation, CMV continues to cause morbidity and mortality in this setting 152930 The CMV pp65 antigenemia assay, a specific quantitative method developed in the early s, has been widely used for the diagnosis of CMV disease and monitoring of responses to antiviral therapy 36 However, this assay sometimes shows false-negative results due to a low-level expression of the pp65 antigen in white blood cells in a small number of patients with definite CMV disease 2022 The labor-intensive nature of the procedure, the requirement for immediate sample processing, and the subjective interpretation of slides place limitations on this assay as a routine diagnostic procedure 416 In addition, the clinical utility of these assays in assessing response to antiviral therapy is uncertain 7 The presence of mRNA pp67 indicates active viral replication, and its detection is a marker for active CMV infection 18 Nevertheless, this assay has less sensitivity than DNA amplification and antigenemia assays for detection of CMV infection.
The lower sensitivity of the assay may result in failure to detect or predict CMV disease in all patients This semiautomated PCR amplification system provides clinical laboratories with a standardized assay for detection and quantitation of CMV in plasma, featuring high sensitivity and specificity.
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However, some disadvantages, such as the cost, the narrow dynamic range of the assay and the time-consuming nature of the procedure, limit the use of CACM as a surveillance tool in high-risk populations 2226 Recently, a fluorescence-tagged, real-time quantitative PCR assay in a closed tube system has been introduced into research and diagnostic laboratories.
A few studies have demonstrated that real-time quantitative PCR is accurate, rapid, and cost-effective with high sensitivity and specificity for the determination of CMV DNA load 10111417222632 In the present study, we report our comparisons of critical parameters, such as sensitivity, specificity, dynamic range, required-time and cost of the LC-PCR, CACM, and pp65 antigenemia assays, running in parallel with the same clinical specimens.
The temporal pattern of number of neutrophils in Clock mutant mice was bimo- dal, whereas the pattern of lymphocytes was similar to that in wild-type mice Fig.
The Clock mutation reduced the numbers of total WBC, lymphocytes and neu- trophils during the light period Fig. In wild-type mice, plasma CS peaked at 9. In contrast, plasma CS levels in Clock mutant mice peaked at The peak CS levels were similar in the two genotypes.
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Figure 3A shows that the number of RBC peaked at 9. However, the amplitude was reduced and the acro- phase was significantly advanced to 4. The acrophase of HGB was Plasma EPO levels were slightly but significantly higher in Clock mutant Plasma EPO levels were not rhythmic in either genotype data not shown. Anatomical examination of Clock mutant mice revealed a swollen red spleen Fig.
The wet weight of the spleen per body weight of Clock mutants was about 1. Discussion The circadian rhythm in the number of circulating blood cells in mammals is highly regular and reproducible .
However, the complex nature of this regulation has pre- vented elucidation of the underlying mechanisms of circa- dian changes in circulating blood cells . The present study found that a homozygous mutation of the circadian clock gene, Clock, affects the circadian fluctuation of circu- lating WBC and RBC in mice. This finding suggests that Circadian variations in plasma corticosterone CS levels in Clock mutant miceFigure 2 Circadian variations in plasma corticosterone CS levels in Clock mutant mice.
Open and filled circles indi- cate values from wild-type and Clock mutant mice, respec- tively. Open and solid bars represent lights on and off, respectively. Circadian variations in peripheral circulatingleukocytes in Clock mutant miceFigure 1 Circadian variations in peripheral circulatingleukocytes in Clock mutant mice.
Open and filled circles, values from wild-type and Clock mutant mice, respectively.
Open and solid bars, lights on and off, respectively. Steroid hormones play important roles in generating the circadian rhythm of circulating blood cells . Patients with an adrenal insufficiency or with adrenal hyperplasia have low and high endogenous cortisol levels together with high and low lymphocyte counts, respectively [18,19]. Corticosteroids cause the efflux of some lym- phocytes from the vasculature and their retention in the lymphatic circulation .
The mechanism through which corticosteroids cause such movements may involve the expression of cell adhesion molecules CAMs [21,22]. The expression levels of leukocytes including lymphocytes, neutrophils, and monocytes and of CAMs are highest when plasma cortisol concentrations are max- imal .
The present study found that the acro- phase of total WBC and lymphocytes numbers was delayed for few hours in accordance with that of plasma CS levels in Clock mutant mice.
We previously reported Swollen red spleens from Clock mutant miceFigure 4 Swollen red spleens from Clock mutant mice. A Spleens from wild-type and Clock mutant mice. Our present results suggested that circa- dian clock-regulated diurnal CS secretion from the adre- nal gland is involved in the effect of the Clock gene mutation on circadian changes in the numbers of periph- eral circulating WBC.
However, the present study identified a circadian CS rhythm in Clock mutant mice with a Jcl: ICR background under LD condi- tions, although the acrophase was delayed in mutant mice.
Mutant CLOCK protein might provoke gain- of-function effects in the mutant mice, because the Clock allele is truncated and causes a deletion of the transactiva- tion domain, which leaves DNA binding intact.
The phe- notypic differences such as CS rhythm, locomotor activity , and metabolism  between the Clock mutant mice with different backgrounds might reflect expression levels of the truncated CLOCK protein, which in the Jcl: ICR background would interfere less with circa- dian and other physiological processes.
On the other hand, a study of blood samples withdrawn over a period of 24 h has established a circadian rhythm in E-rosette-forming T cells in vitro that persists in 4-day- old cell cultures . This finding suggests that fluctua- tions in some lymphocyte subpopulations depend on a cellular circadian oscillator .
We revealed that many cir- cadian output genes, as well as those in the core circadian clock, are governed by CLOCK protein at the level of tran- scription . In the present study, the circadian rhythm of circulating neutrophils was a damped bimodal process in Clock mutant mice, although that of lymphocytes was only phase-delayed. Granulocytes emigrate from the bloodstream to tissues and cannot recirculate, whereas lymphocytes continuously recirculate from tissues through the lymph back to the blood.
We showed here that the circadian fluctuation of circulat- ing RBC is regulated not only by the consequence of phys- iological rhythms such as feeding and sleeping but also by the endogenous circadian clock. The acrophase of the diurnal RBC rhythm is near the light-dark transition in nocturnal mice.
The acrophase of circulating RBC in diur- nally active humans is also at the time of the light-dark transition . This resembles the expres- sion of circadian clock genes in the suprachiasmatic nucleus SCNwhich is the master circadian pacemaker that controls most of the physiological circadian rhythms of mammals.
The expression phase of clock genes Per1 and Per2 in the SCN is almost identical between rodents that are active during the night [9,10] and during the day . Thus, the SCN might tightly regulate the circa- dian phase of circulating RBC in mammals, whereas the phase of WBC seems to be affected by physiological rhythms such as those of feeding, locomotor activity and blood CS levels.
The amplitudes of RBC rhythms are very small and are of interest from a physiological viewpoint . Circulating RBC numbers are determined not only by their clearance from the peripheral circulation in the spleen and liver but also by their production in bone marrow.
Actually, circu- lating reticulocytes have a circadian rhythm, suggesting their circadian periodic release from the bone marrow . We also found that plasma levels of EPO were slightly but significantly increased in Clock mutant mice throughout the day.
Focal segmental glomerulosclerosis lagged behind the onset of rheumatoid arthritis by 7 years
Thus, the Clock mutation may affect the diurnal regulation of RBC production in the bone marrow. The mean cell volume MCV of erythrocytes in the present study did not appear to exhibit circadian rhyth- micity or to show genotypic differences. These results suggest that the availa- bility of erythropoietic iron remained intact in the Clock mutant mice.
The lifespan of circulating RBC produced in bone marrow is determined by their elimination from the spleen. Anatomical Journal of Circadian Rhythms4: Our results also indicated that the Clock mutation affects the circadian regulation of both blood CS levels and peripheral circulating blood cells, but that intact CLOCK is not essential to generate the rhythm.
Further elucida- tion of the functions of circadian clock genes should reveal the underlying mechanisms of circadian changes in mammalian immune functions. Competing interests The author s declare that they have no competing inter- ests. Authors' contributions KO and NO participated in data collection and drafted the manuscript. KK performed a circadian phase analysis.
MK discovered the swollen red spleens in Clock mutant mice. KS and SY helped with data collection. All authors read and approved the final version of the article.
Báo cáo y học: "Clock mutation affects circadian regulation of circulating blood cells" pot
The diurnal variation of blood leuco- cytes in normal and adrenalectomized mice. Haus E, Smolensky MH: Biologic rhythms in the immune sys- tem. Chronobiol Int Studies on the bioperiodic- ity of the immune response. Circadian rhythms of human T, B, and K cell traffic in the peripheral blood. J Immunol Studies of the bioperio- dicity of the immune response. Co-variations of murine T and B cells and a role of corticosteroid.