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The relationship of temporal variability to spatial analyses is discussed. This involves the utilization of a combined spectral and multivariate methodologies on water samples from ground-water overlain by glacial deposits. Most of the spatial variations that occurred among sample locations and attributes during the early summer of 1990 were attributed to three factors.

Metabolism plays a key role in the maintenance of normal hematopoietic stem cells (HSCs) and in the development of leukemia. A better understanding of the metabolic characteristics and dependencies of pre-leukemic cells could help identify potential therapeutic targets to prevent leukemic transformation. As AML1-ETO, one of the most frequent fusion proteins in acute myeloid leukemia that is encoded by a RUNX1::RUNX1T1 fusion gene, is capable of generating pre-leukemic clones, here we used a conditional Runx1::Runx1t1 knock-in mouse model to evaluate pre-leukemic cell metabolism. AML1-ETO expression resulted in impaired hematopoietic reconstitution and increased self-renewal ability. Oxidative phosphorylation and glycolysis decreased significantly in these pre-leukemic cells accompanied by increased HSC quiescence and reduced cell cycling. Furthermore, HSCs expressing AML1-ETO exhibited an increased requirement for fatty acids through metabolic flux. Dietary lipid deprivation or loss of the fatty acid transporter FATP3 by targeted deletion using CRISPR/Cas9 partially restored differentiation. These findings reveal the unique metabolic profile of pre-leukemic cells and propose FATP3 as a potential target for disrupting leukemogenesis.

This study was conducted to explore whether cholecystokinin-B/gastrin receptor (CCKBRwt) gene and its alternative splicing variant (CCKBRi4sv) are expressed in human gastric carcinomas cell line and tissues, and to find out their relationship with the development and progression of human gastric carcinoma. The mRNA expression levels of CCKBRwt and CCKBRi4sv were detected in 30 human gastric carcinomas and normal tissues adjacent to cancer, 10 gastritis specimens, 2 autopsied normal stomach specimens as well as in a gastric carcinoma cell line SGC-7901 cells. The results revealed that the transcripts of CCKBRwt and CCKBRi4sv were observed in all of the human gastric specimens tested, but only CCKBRwt was expressed in gastric cancer cell line SGC-7901 cells. The expression levels of the two receptors were not correlated with the differentiation and metastases of gastric cancers. From the results, we infer that human gastric tissues simultaneously express CCKBRwt and CCKBRi4sv, and CCKBRi4sv may have unknown physiological functions in gastric epithelial cells.

Objective: To investigate the effects of human gastric chorionic gonadotropin (hCG) on the growth of human gastric adenocarcinoma cells., Methods: MTT reduction assay was used to determine the cell growth and survival rates., Results: Within the concentration range of 10(-11)-10(-6) mol/L, hCG could slightly stimulate the growth of gastric cancer cells but in a obvious time-dependent manner., Conclusion: hCG has slightly stimulatory effect on the proliferation gastric adenocarcinoma cells, suggestion that hCG may possibly play a role in regulation the tumorigenesis of gastric cancer.

Objective: To evaluate the effect of insulin and it's receptor on the kidney of rabbit with acute ischemic/reperfusion injury., Methods: Twenty three Japanese white rabbits were allocated randomly into the control group, ischemic/reperfusion group(IR group), and insulin treatment group(Ins-IR group). The IR group received clamping for 1 h followed by 2 h or 48 h of reperfusion. In the Ins-IR group, insulin injection (Ins 3U/kg, glucose 1.5 g/kg, K+ 4 mg/kg, Mg2+ 1.7 mg/kg) was administered intravenously twice a day for two days, whereas only normal saline in equal amount was given to the IR group and control group. At 2 h or 48 h after reperfusion, glucose and insulin in serum were determined. Rough plasma of renal tissue was prepared by repeated centrifugation. Insulin receptor in renal tissue was analyzed by radiologand binding assay. The binding data were calculated according to Scatchard using the ligand program. Statistical significance was analyzed with the paired t-test., Results: The level of blood glucose increased after 2 h reperfusion in three groups, but the level in IR group increased much higher than those in control and Ins-IR groups(P < 0.05). The level of serum insulin of IR group after 2 h reperfusion was significantly higher than that of control (P < 0.05). Scatchard analysis showed curvilinear profiles, indicating that there are two classes of receptors with different affinity or the presence of a single class of receptors with a negative cooperative hormone-receptor interaction. Data analyzed by a two-site model showed that the values of Bmax1 (high affinity site), Bmax2 (low affinity site) and Kd1, Kd2 after 2 h reperfusion were significantly lower than those of control (P < 0.05). In IR-Ins group, only Bmax2 decreased (P < 0.05, compared with control). 48 h after IR there was no difference in Bmax1, Kd1 between the 3 groups, but Bmax2 of IR-Ins group was still lower than that of control (P < 0.001) and IR group (P < 0.05). The Kd2 of IR group increased (P < 0.05 compared with control and IR-Ins group)., Conclusion: The results indicate that the effect of intrinsic insulin decreases during renal ischemic/reperfusion. The extrinsic insulin can protect renal tissue through its high affinity receptor. There exits down-regulation of low affinity receptor but none of high affinity receptor during insulin treatment.

Objective: To determine the relationship between double-contrast manifestation and 5'-nucleotidase (5'-NT) of gastric carcinoma., Methods: Serum specimens were taken from 41 cases with gastric carcinoma documented by double-contrast visualization and pathology. 5'-NT activity was determined by spectrophotometry. 40 healthy subjects were recruited and studied as normal controls., Results: The serum level of 5'-NT(1.14 u/ml) in gastric carcinoma group was lower than that of control group (2.60 u/ml) (P < 0.05). Anatomically, it was found that the 5'-NT level of gastric carcinoma gradually increased as the sites of the tumor lined up from the orifice (0.98 u/ml) to the antrum (1.28 u/ml) via the body (1.20 u/ml). 5'-NT of the ulcerative type (0.96 u/ml) was lower than that of the fungating type (1.12 u/ml) or the infiltrating type (1.40 u/ml). 5'-NT(1.53 u/ml) of stage IV gastric carcinoma was higher than that of stage 1 (0.83 u/ml), stage I (0.98 u/ml) and stage III (1.03 u/ml) (P < 0.05)., Conclusion: The change of 5'-NT from gastric carcinoma was correlated with the site, type or stage shown on the double-contrast images of the tumor.

Objectives: To improve the accuracy and precision of the determination of bilirubin, especially direct bilirubin (DB), and the standardization of that as well., Methods: Purified conjugated bilirubin (Bc) and ditaurobilirubin(DTB) and their diazo products were subjected to absorption spectrum analysis. The diazo reaction characters of their calibration solutions were compared by the method of Doumas J-G(TB & DB)., Results: Bc, DTB and their azopigments were found to have the similar absorption spectra with the same lambda max. Their TB standard curves almost superposed together all over. Although the slopes of their DB standard curves were not markedly different ((YBc = 0.00366X + 0.00933, rBc2 = 0.9977, P < 0.01; YDTB = 0.00391X + 0.00023, rDTB2 = 0.9987, P < 0.01; Pb1-b2 > 0.05, n1 = n2 = 5), the DB value measured for Bc differed from that for DTB(n = 5, P < 0.05). In addition, the calibrators made from Bc based different matrices, such as HSA, BSA and human serum, were significantly different in DB/Bc, but no difference was seen among the concentrations. Furthermore, the DB values determined for DTB or Bc increased linearly with the corresponding concentrations, respectively, with no difference between the slopes (YBc = 0.8300XBc + 1.9463, rBc2 = 0.9977, P < 0.01; YDTB = 0.8853XDTB-0.0251, rDTB2 = 0.9986, P < 0.01; n1 = n2 = 5, Pb1-b2 > 0.05)., Conclusions: The results demonstrate that the diazo reaction characters of Bc are identified with those of DTB. However, under the condition of DB, Bc reacts differently from DTB. This study also indicates that as a calibrator of DB based human serum, Bc has the similar constant effect of HCl as serum samples do, so it is a more reliable calibrator to eliminate the matrix effects.

Objective: To investigate the effects of CCK8 on protein kinase C activity in rat cerebral cortex., Methods: The cerebral cortex neurocytes were isolated and used as a model. The effects of CCK8, L-364, 718 and L-365, 260 on PKC activities were detected by using a non-radioactive method., Results: CCK8 caused a detectable increase in PKC activity at 10(-11) mol/L, and a peak increase of PKC activity was observed at 10(-5) mol/L (about 4.5 U/mg protein). PKC activity was increased in dose-dependent manner by CCK8(10(-11)-10(-6) mol/L). The CCKB-selective receptor antagonist L-365, 260 with a higher efficiency, and the CCKA-selective receptor antagonist L-364, 718 with a lower efficiency were able to block a maximal effect of CCK8-induced PKC activation., Conclusions: CCK8 may regulate PKC activities in rat cerebral cortex through CCKB receptor.