A comparative study of the estimation of calcium in serum

Five generally applied methods for the estimation of calcium in serum were compared as to their precision, accuracy, speed and productivity. The influence of storage at 4°C and ?20°C and of a number of possible interfering factors were also investigated.As a result the continuous flow method with acid dialysis according to H.J. Gitelman (Anal. Biochem., 18 (1967) 521) in the modification of Teehnicon appeared to meet these conditions the most.     

Quantitative determination of non-haem iron and ferritin iron in bone marrow using flameless atomic absorption spectrophotometry. A comparative study on the cytological and chemical determination of the bone marrow iron content

A method for non-haem iron analysis in bone marrow aspirates using graphite furnace atomic absorption spectrophotometry has been developed. Bone marrow aspirates were obtained from patients with various disorders. A good correlation is observed between chemical and cytological assessment of total non-haem iron in bone marrow. An intra-assay coefficient of variation of 9.0% was observed. The ferritin-iron concentration was also determined and a CVduplo of 11% was found. The ferritin iron concentration increased with an increasing total iron content until saturation of ferritin appeared to be reached at about 3 g ferritin per kg protein. It was concluded that the quantitative determination of bone marrow iron can be of value in the diagnosis and investigation of both hypo- and hyper-ferraemic disorders.     

A comparative study of manual methods for serum triglyeride estimation

A comparison is made of the accuracy, precision, and convenience of two manual serum triglyceride methodologies based on solid phase adsorption and liquid phase partition procedures. Both methods are accurate but the precision and convenience of the latter is far superior. The use of home made reagents reduces the cost of both substantially below that of any commercial alternative, including the popular enzymatic methods.     

The production of calcification in connective tissue and skeletal muscle using various chemical compounds.

The subcutaneous injection into mice of small quantities of lead salts resulted in calcification of the dorsal fascia. Other reputed calcergens failed to produce a similar reaction. However, the injection of Zn Cl2 and KMn O4 in high doses caused damage to, and subsequent calcification of the panniculus carnosus muscle.     

A comparative study of steroid concentrations in human adipose tissue and the peripheral circulation

Using radioimmunological methods, levels of cortisol, dehydroepiandrosterone, androstenedione, testosterone, oestrogens (oestradiol + oestrone), progesterone and 17 alpha-hydroxyprogesterone were determined in adipose tissue and peripheral blood obtained during surgical treatment of patients with non-endocrine diseases. The steroid content of human adipose tissue was observed to be extremely high relative to that in the general circulation, giving a tissue/serum ratio of 0.4 to 13.2. The concentration of steroids decreased in the following order: dehydroepiandrosterone greater than cortisol greater than androstenedione greater than progesterone greater than testosterone greater than 17 alpha-hydroxyprogesterone greater than oestradiol + oestrone. This sequence is different from that found in blood. When anthropometric variables were taken into consideration, the adipose tissue mass of severely obese subjects contained a steroid pool far greater than that in the total blood volume.     

Accumulation of iron oxide particles around liver metastases during MR imaging

The histologic nature of the bright ring (peritumoral edema) around some liver metastases on T2-weighted magnetic resonance (MR) images is controversial. In the case reported, particles of the iron oxide contrast agent AMI-25 are retained in the peritumoral zone of a colon cancer metastasis, causing the bright ring to disappear. The location of iron particles in resected specimens could be used systematically to study peritumoral edema.     

A comparative study and assessment of Doppler ultrasound spectral estimation techniques. Part I: Estimation methods

When compared to the classical Discrete Fourier Transform (DFT) or Fast Fourier Transform (FFT) approach, modern estimation methods offer the potential for achieving significant improvements in estimating the power density spectrum of Doppler ultrasound signals. Such improvements, for example, might enable minor flow disturbances to be detected, thereby improving the sensitivity in arterial disease assessment. Specifically, reduction in the variance and bias can be achieved, and this may enable disturbed flow to be detected in a more sensitive manner. The approach taken here, is to consider spectral estimation methods as a problem of fitting an assumed model to the Doppler signal. The models described assume that the signal is stationary. Since the Doppler signal is generally nonstationary, it is assumed that a short enough time window interval can be chosen over which the signal can be considered stationary. We shall review the various methods and when appropriate, relate them to the nature of the Doppler signal.     

A network pharmacology study on main chemical compounds from Hibiscus cannabinus L. leaves

Hibiscus cannabinus L. leaves (HCLLs) are considered a favorable source of natural antiobesity substances. However, actual bioactive compound(s) in it and their mechanism(s) against obesity have not been confirmed. Hence, network pharmacology was conducted to identify its key compounds and mechanism(s) against obesity. Compounds in HCLLs were identified through GC-MS analysis and screened by Lipinski''s rule. Genes related to the selected compounds and obesity were obtained from public databases, and overlapping genes between HCLL compound-related genes and obesity target genes were selected using a Venn diagram. The networking between selected compounds and overlapping genes was then constructed, visualized, and analyzed by RStudio. Finally, the binding affinity between compounds and genes was evaluated via molecular docking (MD). A total of 30 compounds in HCLLs were detected via GC-MS, and Lipinski''s rule accepted all compounds. The compound-related genes (570 genes) and obesity targeted genes (3028 genes) were identified, and between them, 64 overlapping genes were selected. Gene Set Enrichment Analysis (GSEA) displayed that the mechanisms of HCLLs against obesity were associated with 13 signaling pathways on 22 compounds in HCLLs. Superficially, AKT1, vitamin E, and RAS signaling pathways were noted as a hub gene, an uppermost bioactive compound, and a hub signaling pathway, respectively. However, the binding affinity of ligands and proteins on the RAS signaling pathway was very low; instead, the PPAR signalling pathway was evaluated with potent efficacy against obesity through MD. On the PPAR signaling pathway, α-amyrin was found as the most significant compound for the amelioration of obesity. α-Amyrin manifested the strongest binding affinity on six target proteins associated with the PPAR signaling pathway. Our study suggests that an auxiliary (PPAR) signaling pathway of HCLLs might intervene efficiently against obesity over the hub (RAS) signaling pathway.

Hibiscus cannabinus L. leaves (HCLLs) are considered a favorable source of natural antiobesity substances.     

Erythropoiesis, iron stores and tissue iron exchange in man.

1. The exchange of iron between plasma and erythroid and non-erythroid tissues was measured in 14 normal subjects, 17 iron-deficient patients, nine patients with primary idiopathic haemochromatosis and in 13 patients with haemolytic disorders. 2. The two main factors determining tissue iron turnover were shown to be the level of iron stores and the erythropoietic activity of the bone marrow.     

A comparative study on estradiol receptor assays in human breast cancer tissue

Standard dextran-coated charcoal assays for measuring the estrogen receptor content in human breast cancer tissue are compared. A single-point assay, using the estrogen antagonist nafoxidine as competitive inhibitor, showed good qualitative agreement with a three-point Scatchard plot assay, using radio-inert estrogen to assess the non-specific binding. Based on statistically evaluated dividing points, 116 (66.3%) of the 175 analysed primary tumor specimens were positive in the single-point assay compared to 121 (69.1%) in the Scatchard plot assay. Use of the additional dissociation constants in the evaluation of the Scatchard plot assay data gives a complete qualitative agreement between the two assays. We conclude that, in spite of the lack of specific controls inherent in the Scatchard plot assay, the single-point assay using diethylstilbestrol instead of nafoxidine is equally useful, especially if biopsy specimens are too small to provide the larger number of aliquots necessary for multiple steroid receptor analyses. Factors affecting the quantitative differences between the two assays are discussed.     

7.0T MRI对离体乳腺癌组织浸润范围判定的病理对照研究

目的评估MRI技术判定乳腺癌肿瘤边界的准确性,验证MRI技术在手术前判断乳腺癌浸润范围的价值。材料与方法新鲜乳腺离体标本17个,离体后迅速行MR扫描及病理检查,在7.0 T MR成像仪上采集乳腺癌离体样本的MR T1WI、T2WI和扩散加权成像(DWI)。通过Vnmr J 4.0计算出表观扩散系数像(ADC)及各向异性分数像(FA)。在Vnmr J 4.0软件上对DWI、ADC和FA图通过手工勾绘病变范围,并计算病变面积。在显微镜下标记病理切片的病变范围,通过Photoshop软件计算病变面积,最后比较上述图像的病变范围与病理染色切片的病变范围差异。结果在送检的乳腺癌标本中,经病理证实14例为乳腺浸润性导管癌,2例为乳头状癌,1例为黏液腺癌。结合不同序列的MRI可观察到乳腺肿瘤边缘的浸润范围。经过spss19.0软件分析,发现MR DWI、ADC及FA像的病变面积与病理标本浸润范围具有显著的相关性;DWI平均面积[(4.32±1.28)cm2]与病理平均面积[(3.81±1.12)cm2]比较,r=0.966,P0.01;ADC平均面积[(4.68±1.43)cm2]与病理平均面积[(3.81±1.12)cm2]比较,r=0.976,P0.01;FA平均面积[(4.74±1.53)cm2]与病理平均面积[(3.81±1.12)cm2]比较,r=0.964,P0.01)。结论 7.0 T MRI ADC图和FA图在评估肿瘤浸润范围具有更明显的价值,病变面积与病理结果有很高的相关性,可为乳腺癌术前病变范围评估提供重要的参考信息。     

Injection of iron compounds followed by induction of the stress response causes tissue injury and apoptosis

To determine whether iron-laden tissue subsequently stimulated to produce the stress ("heat shock") response-sustained injury, hindlimbs of male ND4 mice were injected with iron salts, hemin, or hemoglobin. The stress response was induced with sodium arsenite or with heat. Ulcers appeared at the injection site. Tissues were analyzed by three distinct techniques-electron microscopy, TUNEL stain, and agarose gel electrophoresis of low molecular weight DNA-which collectively suggest that the tissue injury is, at least in part, the consequence of accelerated apoptosis. The data suggest that the toxicity of free iron is amplified by induction of the stress (heat shock) response to signal a programmed response. This model and mechanism may have implications in pathological processes ranging from the cutaneous wounds of venous stasis disease to the tissue failure of multiple organ dysfunction.     

Accumulation of hyaluronan and tissue edema in experimental myocardial infarction.

Experimental myocardial infarction was induced in rats. The myocardial accumulation of hyaluronan (HA) and water during the development of infarction was measured. The extractable HA content of the infarcted area increased progressively from day 1 and on day 3 reached a threefold increase compared with the HA amounts in myocardium of sham operated controls. The relative water content of infarcted areas also increased progressively reaching a maximum value by day 3 and was strongly correlated with the HA accumulation. Affinity histochemistry visualized a thin rim of HA in the endoperimysium in healthy myocardium. By day 2 an interstitial edema with inflammatory cells was apparent. The widened endoperimysium stained extensively for HA. By its water-binding ability, interstitial accumulation of HA will contribute to the interstitial edema in infarcted myocardial tissue. An interstitial edema is likely to influence the electromechanical characteristics of the myocardium and facilitate reentry phenomena due to a loss of contact between muscle cells. The edema also induces an increased extracellular pressure and an altered myocardial wall compliance that might impair myocardial microcirculation. The findings are relevant to an understanding of the beneficial effect of hyaluronidase treatment in limiting cellular damage during myocardial ischemia.