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Introduction: Procrastination is a maladaptive behavior that leads to failure of tasks, and a decrease in self-esteem and negative emotions; this behavior, however, becomes a habit. If procrastination becomes a habit, it will have a negative impact on your body and mind. Previous studies have divided participants by gender, age, etc., and relationships between procrastination and stress have been examined. However, a general relationship between procrastination and stress has not been clarified. This study examined the relationship between procrastination and stress through a questionnaire survey. Methods: This study also examined the effects of passive or active procrastination on stress responses through a survey on active procrastination tendency. In addition, surveys were conducted on Japanese and Chinese people, and their answers were analyzed and compared between them. Hypotheses in this study are as follows: there are relationships between the participants’ general procrastination tendency and stress responses (Hypothesis 1); participants with higher general procrastination tendency show higher stress responses than those with higher active procrastination tendency (Hypothesis 2). There are differences in relationships between procrastination tendencies and stress responses between Japanese and Chinese participants (Hypothesis 3). The results of the analysis have been discussed based on differences in cultural and social backgrounds. Results: These results showed a positive correlation between general procrastination and stress response in both Japanese and Chinese populations. Active procrastination was found to be positively correlated with stress response in Japanese and negatively correlated in Chinese. Conclusion: The results suggest that the relationship between procrastination and stress response is influenced by the subject's cultural background.

Two cadmium(II) complexes based on 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)benzoate with chemical formulas of [Cd2(ppb)4(H2O)2]·8H2O (1) and [Cd(Hppb)I2]n (2) (Hppb = 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)benzoic acid), have been synthesized. Both complexes are well characterized by IR, TGA and X-ray single-crystal as well as powder diffraction. Structural analyses reveal that 1 is a binuclear complex and 2 has one-dimensional polymers, respectively, in which they are expanded to three-dimensional supramolecular structures by hydrogen bonds. The Cd(II) coordinated environments in 1 are slightly distorted octahedral geometries, but central atoms in 2 display distorted square pyramidal geometries. There are obvious differences in ligation modes of the ppb− or Hppb ligands for both complexes. In 1, four ppb− ligands are divided into two groups, displaying µ1-kN, N′ and µ2-kN, N′: kO coordination modes. Two ppb− ligands act as two µ1,6-bridges linking the binuclear Cd(II) cations with a distance of 6.282(2) A. In 2 the neutral Hppb ligands exhibit a µ2-kN, N′: kO coordination mode, and connecting Cd(II) ions by µ1,6-bridges and forming an infinite 1D chain along b axis. Hirshfeld surfaces and fingerprint plots analyses indicate that weak interactions of C–H···π, π···π, O–H···O or O–H···I play important roles in crystal packings of 1 and 2. Luminescent measurements in solid-state show their different intensities in the luminescences of 1 and 2. A binuclear complex [Cd2(ppb)4(H2O)2]·8H2O (1) and a one-dimensional complex [Cd(Hppb)I2]n (2) were synthesized and characterized by X-ray crystal diffraction. Investigation of solid-state luminescence properties indicates the blue shifts of the emission λmax of complexes.

Based on a bifunctional 2-(pyridine-2-yl)-1H-4,5-imidazole-dicarboxylic acid ligand, a novel family of lanthanide coordination polymers with formulas [Ln(HPIDC)(C2O4)0.5(H2O)]n (Ln = La, 1; Ce, 2) and [Ln2(HPIDC)(C2O4)2(H2O)3]n·2nH2O (Ln = Pr, 3; Nd, 4; Sm, 5; Eu, 6; Gd, 7; Tb, 8; Dy, 9; Ho, 10; Er, 11), (H3PIDC = 2-(pyridine-2-yl)-1H-imidazole-4,5-dicarboxylic acid & H2C2O4 = oxalic acid) has been prepared under hydro-solvothermal conditions and characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, and thermogravimetric analysis. Notably, the ligands adopt the same μ3-kN,O:kO′,O′′:kO′′′ conformation in all compounds, which brings about two types of isostructural lanthanide coordination polymers. Namely, 1 and 2 crystallize in the monoclinic space group P21/n and are composed of [Ln2(COO)2] dinuclear subunits with networks having the symbol (63·82·10)2(63)2(8). Meanwhile, 3–11 crystallize in the monoclinic space group P21/c and are constructed with tetranuclear [Ln4(COO)4] subunits with networks having the symbol (103)2(104·122)(10)2. The photoluminescence measurement indicates that Eu(III) and Tb(III) coordination polymers show very strong reddish-orange and green emission bands with CIE chromaticity coordinates (0.612, 0.325) and (0.284, 0.523) and quantum yields of 54.3% & 34.7%, respectively. The magnetic properties of 3 and 7–11 are investigated, and the results indicate a ferromagnetic interaction between Gd(III) magnetic centers in complex 7 and antiferromagnetic interactions in other complexes.

Cartilage is a relatively simple connective tissue that plays a variety of roles in the human body, including joint support and protection, load bearing of the intervertebral discs, joint lubrication, formation of the external structure of the ears and nose and support of the trachea. The maintenance of cartilage homeostasis is therefore crucial. Cartilage-related diseases are difficult to diagnose and treat because their molecular and pathological mechanisms are not fully understood. Melatonin, which has a wide range of physiological effects, is an endocrine hormone mainly secreted by the pineal gland. Its biological effects include its antioxidant, antiaging, analgesic, and hypnotic effects and its ability to stabilize the circadian rhythm. In recent years, research on cartilage homeostasis and melatonin has been increasing, and melatonin has gradually been used in the treatment of cartilage-related diseases. Therefore, this article will briefly review the role of melatonin in cartilage homeostasis, including its anti-inflammatory effects and effects in protecting cartilage from damage by other factors and promoting chondrocyte growth and the expression of cartilage-related genes. Based on the above, the current status and future developmental direction of melatonin in the treatment of cartilage-related diseases are also discussed, demonstrating the broad prospects of melatonin in maintaining cartilage homeostasis and treating cartilage injury-related diseases.

To investigate the effect of Mn on antioxidant status and on the expressions of heat shock proteins/factors in tissues of laying broiler breeders subjected to heat challenge, we used a completely randomised design (n 6) with a factorial arrangement of 2 environmental temperatures (normal, 21±1°C, and high, 32±1°C)×3 dietary Mn treatments (a Mn-unsupplemented basal diet (CON), or a basal diet supplemented with 120 mg Mn/kg diet, either as inorganic Mn sulphate (iMn) or as organic Mn proteinate (oMn)). There were no interactions (P>0·10) between environmental temperature and dietary Mn in any of the measured indices. High temperature decreased (PP=0·07) to decrease Cu Zn superoxide dismutase (CuZnSOD) activity in the liver and heart. However, an increased Mn superoxide dismutase (MnSOD) activity (P·05) and a slight increase in malondialdehyde level (P=0·06) were detected in breast muscle. Up-regulated (PHSF1) and HSF3 mRNA and heat shock protein 70 (HSP70) mRNA and protein were found in all three tissues. Broiler breeders fed either iMn or oMn had higher tissue Mn content (PPPPHSP70 mRNA and protein levels compared with those fed CON. Broiler breeders fed oMn had higher (PHSF1 and HSF3 expressions in the tissues of laying broiler breeders. Furthermore, dietary supplementation with Mn in either source may enhance the heart’s antioxidant ability and inhibit the expression of HSP70 in breast muscle. Finally, the organic Mn appears to be more available than inorganic Mn for bone in laying broiler breeders regardless of environmental temperatures.

This experiment was conducted to evaluate the effects of Acremonium terricola culture (CAT) on growth performance, antioxidant status and immune responses of weaned calves. Twenty-four weaned female Holstein calves of the same age and with a similar genetic background were randomly assigned to one of two treatments for a 40 day feeding period. Treatments consisted of feed supplemented with (1) nothing (i.e., the control group) or (2) 50 mg CAT/kg of body weight (BW). Feed, fecal and blood samples were collected on days 0, 20 and 40. The seventh day after weaning was defined as Day 0. The results demonstrated that CAT supplementation increased body weight, feed efficiency and average daily weight gain compared to the control group. Supplementation with 50 mg of CAT/kg of BW significantly increased concentrations of immunoglobulins A, M, and G, interleukin-4, as well as the ratio of soluble CD 4 /soluble CD 8 , activities of total antioxidant capacity, glutathione peroxidase and total superoxide dismutase in plasma. In contrast, CAT supplementation resulted in a significant reduction in the concentrations of interleukin-1, interleukin-6, tumour necrosis factor – alpha, cortisol and malondialdehyde in plasma. These results suggested that supplementation with 50 mg of CAT/kg of BW may enhance growth performance and antioxidant and immune functions in weaned calves.

Coordination polymers are a thriving class of functional solid-state materials and there have been noticeable efforts and progress toward designing periodic functional structures with desired geometrical attributes and chemical properties for targeted applications. Self-assembly of metal ions and organic ligands is one of the most efficient and widely utilized methods for the construction of CPs under hydro(solvo)thermal conditions. 2-(Pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate (HPIDC2−) has been proven to be an excellent multidentate ligand due to its multiple deprotonation and coordination modes. Crystals of poly[aquabis[μ3-5-carboxy-2-(pyridin-3-yl)-1H-imidazole-4-carboxylato-κ5N1,O5:N3,O4:N2]copper(II)dicopper(I)], [CuIICuI2(C10H5N3O4)2(H2O)]n, (I), were obtained from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylic acid (H3PIDC) and copper(II) chloride under hydrothermal conditions. The asymmetric unit consists of one independent CuIIion, two CuIions, two HPIDC2−ligands and one coordinated water molecule. The CuIIcentre displays a square-pyramidal geometry (CuN2O3), with twoN,O-chelating HPIDC2−ligands occupying the basal plane in atransgeometry and one O atom from a coordinated water molecule in the axial position. The CuIatoms adopt three-coordinated Y-shaped coordinations. In each [CuN2O] unit, deprotonated HPIDC2−acts as anN,O-chelating ligand, and a symmetry-equivalent HPIDC2−ligand acts as an N-atom donorviathe pyridine group. The HPIDC2−ligands in the polymer serve as T-shaped 3-connectors and adopt a μ3-κ2N,O:κ2N′,O′:κN′′-coordination mode, linking one CuIIand two CuIcations. The Cu cations are arranged in one-dimensional –Cu1–Cu2–Cu3– chains along the [001] direction. Further crosslinking of these chains by HPIDC2−ligands along thebaxis in a –Cu2–HPIDC2−–Cu3–HPIDC2−–Cu1– sequence results in a two-dimensional polymer in the (100) plane. The resulting (2,3)-connected net has a (123)2(12)3topology. Powder X-ray diffraction confirmed the phase purity for (I), and susceptibilty measurements indicated a very weak ferromagnetic behaviour. A thermogravimetric analysis shows the loss of the apical aqua ligand before decomposition of the title compound.

An experiment was carried out to investigate the relative bioavailability of tribasic zinc (Zn) sulfate relative to Zn sulfate for broilers fed a conventional corn-soybean meal diet. A total of 504 1-d-old Arbor Acres commercial male chicks were randomly assigned by body weight of birds to one of seven treatments involving a 2×3 factorial arrangement with three levels of added Zn (30, 60, or 90 mg of Zn kg−1) and two Zn sources (tribasic Zn sulfate and Zn sulfate) plus a control with no added Zn for an experimental phase of 14 d. Plasma Zn, tibia ash Zn, pancreas Zn, and pancreas metallothionein (MT) messenger RNA (mRNA) were analyzed at 6 or 14 d of age post-hatching. The results showed that plasma Zn, tibia ash Zn, pancreas Zn, and pancreas MT mRNA increased linearly (P

Rationale: Langerhans cell histiocytosis (LCH) involves mainly the skin and bone and rarely the thyroid. Meanwhile, papillary thyroid carcinoma (PTC) is the most common subtype of thyroid cancer. Both LCH and PTC could make the thyroid enlarged and hypermetabolic. The coincidence of these 2 events in a patient is rare, and this paper aimed to report such case. Patient concerns: A 40-year-old man presented with polyuria and polydipsia for 5 years. The symptoms had been relieved well by drug therapy for >4 years, until the drugs could not control the symptoms anymore and an extensively enlarged thyroid gland was noticed. Diagnoses: Thyroid ultrasound showed a nodule with microcalcification in the upper right lobe, positron emission tomography/computer tomography scan demonstrated thyroid hypermetabolism, and fine needle aspiration (FNA) revealed PTC. Right lobectomy of the thyroid and cervical lymph node biopsy verified the diagnosis “LCH of the thyroid complicated by PTC.” Interventions: The ultrasound-guided FNA biopsy was performed prior to right lobectomy of the thyroid and cervical lymph node biopsy. Postoperative histopathological examination confirmed the diagnosis, after which the patient received adjuvant chemotherapy. Outcomes: After 5 cycles of adjuvant chemotherapy, the patient had been followed up for 2 years. LCH was controlled satisfactorily and there was no significant sign of recurrence or metastasis of PTC. Lessons: LCH of the thyroid complicated by PTC is rare. Thyroid involvement should always be considered in the differential diagnosis of LCH patients. Surgery for PTC followed by chemotherapy for LCH may be the suitable treatment.

In this paper, the interaction between human serum album (HSA) and minocycline (MNC) in physiological solution had been studied by fluorescence spectroscopy, UV spectrum and FT-IR spectroscopy. The inner filter effect was corrected. The results indicated that the fluorescence quenching of HSA was primarily due to static quenching, and thermodynamic parameters exhibited hydrogen bond and van der Waals force played the major role in stabilizing HSA-MNC complex. Through site marker competitive experiments had been assigned to possess the high-affinity binding site for MNC in subdomain IIA of HSA. Binding constant was obtained to be 1.64×106L·mol-1(298K) and 1.16×104L·mol-1(310K), the number of binding sites were both 1. The alternations of HSA secondary structure, such as α-helix and β-sheet were quantitatively calculated from FT-IR.

The Full decoration residential comply with the developed economic and improved residents' living standards. On the basis comparing the decorate between China and western countries, The full decoration residential should take systematic design and pay attention to the decorate strategy.

The content characteristics, pollution evaluation and source identification of 6 heavy Metals (Cd, Pb, Cr, As, Cu and Zn) in filtered water and 9 heavy Metals (Cd, Pb, Cr, Ni, Cu, V, Co, Zn and Mn) in suspended particles from 10 sampling sites such as Zhaojunfuqiao (S1) and Baotoufuqiao (S2), etc. from Gansu, Ningxia and Inner Mongolia sections of the Yellow River in 2012 Wet Season were studied to understand the condition of the heavy metal pollution in Gansu, Ningxia and Inner Mongolia Sections of the Yellow River by using high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). Multivariate geochemical approaches and statistical analysis were also exploited for assessing the level of heavy metals in filtered water and suspended particles from studied area. The results showed that in filtering water, only the concentrations of Cr exceeded the standard value of Environmental Quality Standard for Surface Water (GB3838-2002) and were the highest (74.8-94.7 μg x L(-1)) among all elements in 10 sampling sites; Single factor pollution index (I(i)) results suggested that the water quality in all sampling sites were contaminated by both Cr and total nitrogen (TN), with the exception of TN in Baotoufuqiao (S2); Integrated Nemerow pollution index (I) indicated that the I values in all sampling sites were between 1-2 (light pollution), which implied that the water quality in Gansu, Ningxia and Inner Mongolia sections, especially downstream sections (S1-S6) of the Yellow River wasn't an ideal source for drinking and using in aquaculture any more. In suspended particles, concentrations of heavy metals were relatively higher than their soil background values in 10 sampling sites, except Ni in S10 (34.7 μg x L(-1)). Index of geo-accumulation (I(geo)) indicated that the I(geo) values of Pb, Cr, Ni, Cu, V, Co, Zn and Mn in all sampling sites were less than 1 (unpolluted or unpolluted-moderately polluted), respectively, while I(geo)Cd were the highest in 10 sampling sites among all heavy metals and with the moderately to strong contamination in Zhaojunfuqiao (S1), Baotoufuqiao (S2), Wuhai (S5) and Dongdagouruhuanghekou (S8). The results of this paper would help to supply reliable experimental data for researching of distribution, migration and effective protection of heavy metals in study area.

So far, many investigations had been made on the concentration and species distribution of heavy metals in aquatic environments. However, there are only a few studies on heavy metals in upper reaches of the Yellow River, especially in Gansu, Ningxia and Inner Mongolia sections. We have literatures related to the Yellow River, in this work, we remarkably discussed about the contents, speciation and potential risks of Cd, Pb, Cr, V, Co, Ni, Cu, and Zn in surface sediments from 12 sampling sites in Gansu, Ningxia, and Inner Mongolia sections of the Yellow River of China in 2011 year wet season by high resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) and sequential extraction procedure of BCR method. The results indicated that the metals contents were arranged as CrVZnCuNiPbCoCd in all sites. Comparing with the background value of soil in local section, Cd showed the highest level at S5 (1.30 μg x g(-1)), which was almost 13 times higher than the background value (0.103 μg x g(-1)). Pollution assessment indicated that Cd presented a strong polluted status with the geo-accumulation index (I(geo)) value of 3.08 at S5, moderately to strong polluted status with the I(geo) ranged from 2.02 to 2.90 in Inner Mongolia section (S1-S4). Moreover, enrichment factor (EF) showed that all heavy metals in these sediments have been influenced by anthropogenic activities. According to potential ecological risk index (RI), S5 and S3 demonstrated high ecologic risk of heavy metals, while other sampling sites showed moderately ecological risk. The results of BCR exhibited that Cd was the most available metal, followed by Co and Ni, while V and Cr were unavailable in the sediments. Risk assessment code (RAC) exhibited high risk for Cd at S1-S4 and very high risk at S5, while medium risk for Ni and Co at all sites. The results and conclusions may be important information and therefore of interest to the relevant departments of the governments.

Multi-station turntable, widely used in industrial automation field, has become an indispensable device in the automation assembly line. The positioning accuracy of traditional mechanical turntable is largely affected by the machining accuracy of Geneva wheel, Ratchet and Cam. The positioning accuracy level has a crucial influence on processing and assembly accuracy, and production efficiency. This paper presents a measuring method to measure positioning accuracy by eddy current sensor. To achieve the positioning accuracy the writer measures the distance between the probe and the measuring block in the circumferential tangent direction. When the turntable turns to a station, the sensor probe is manually adjusted to align it with the measuring block. In this way, the positioning accuracy can be measured conveniently and directly.

The ubiquitin E3 ligase CUL4A plays important roles in diverse cellular processes including carcinogenesis and proliferation. It has been reported that the expression of CUL4A can be induced by hypoxic-ischemic injury. However, the effect of elevated expression of CUL4A on hypoxia-reoxygenation injury is currently unclear. In this study, human CUL4A (hCUL4A) was expressed in rat pheochromocytoma (PC12) cells using adenoviral vector-mediated gene transfer, and the effects of hCUL4A expression on hypoxia-reoxygenation injury were investigated. In PC12 cells subjected to hypoxia and reoxygenation, we found that hCUL4A suppresses apoptosis and DNA damage by regulating apoptosis-related proteins and cell cycle regulators (Bcl-2, caspase-3, p53 and p27); consequently, hCUL4A promotes cell survival. Taken together, our results reveal the beneficial effects of hCUL4A in PC12 cells upon hypoxia-reoxygenation injury.

BACKGROUND: Biofoam composites were prepared using short sisal fibers as reinforcement and acrylated epoxidized soybean oil as matrix, aiming at replacing traditional unsaturated polyester foams in structural applications. The compressive properties of the composites were examined as a function of fiber loading, fiber length and foam density. RESULTS: The foam composite with 10 phr (parts per hundred of base resin by weight) sisal fiber possessed properties similar to those of commercial unsaturated polyester foams. A study of the failure mechanism revealed that debonding between fiber and matrix was a key issue responsible for catastrophic damage of the composites. According to this finding, surface pre-treatment of the sisal using an alkali or silane coupling agent was carried out. This brought about positive effects on interfacial interaction and compressive strength of the composites, as desired. Also, soil burial tests proved that the foam composites could be biodegraded, and the incorporated sisal fibers accelerated the biodegradation of the composites. CONCLUSION: This work shows the feasibility of making rigid biofoams from natural resources, which could be potential candidates for structural foams. Copyright © 2009 Society of Chemical Industry

The mechanisms and tendency of freckle formation in industrial scale ESR ingots were studied bythermodynamic calculation, thermo-physical property calculation, metallographic observation, and compositionanalysis. The macrostructure and compositions of the freckle regions in a low alloy ultrahigh strength ESR steelingot were investigated to clarify the freckle formation mechanism. Combining the results with compositionanalysis and thermodynamic calculation, it can be concluded that the compositions of freckles correspondto that of liquid with a liquid fraction of 0.24 to 0.41, and the freckles were caused by the upward solute-richliquid flow which initiate at the lower part of mushy zone. The relative Rayleigh number (Ra), a freckle criterionconsidering the effect of a tilted solidification front, was adopted to evaluate the freckle formation tendencyin the industrial scale ESR ingots. The calculated results of Ra numbers of different locations are in goodagreement with the actual distribution of the freckles in the ingot.

E. coli and S. cerevisiae were encapsulated within alginate/cellulose sulphate–CaCl 2 /poly(methylene-co-guanidine) (SA/CS–CaCl 2 /PMCG) capsules. Although PMCG inhibited strongly the growth of E. coli and S. cerevisiae in free cultivation, PMCG coated capsules had no negative effects on the growth of free E. coli and S. cerevisiae or on the consumption of glucose in the cultivation of S. cerevisiae . If commercial PMCG agent was pre-treated by the method specified in this paper, E. coli and S cerevisiae immobilised in the SA/CS–CaCl 2 /PMCG capsules grew almost as normally as in free cultivation. Thus, PMCG was shown to be a suitable membrane material for microorganism encapsulation after it was purified under appropriate conditions.

Levofloxacin (LVFX) is widely used in clinical treatment due to it has a broad spectrum of in vitro activity against Gram-positive and Gram-negative bacteria. Human serum albumin (HSA) is the most abundant protein in plasma and constitutes approximately half of the protein founds in human blood. And more than 90% of the drugs used in people are bound to HSA. So it is commonly used for the investigation of drug-serum albumin interaction because the binding will significantly influence the absorption, distribution, metabolism excretion, stability and toxicity of the drugs. Therefore, detailed investigating the interaction of LVFX with HSA is very important to understand the pharmacokinetic behavior of the LVFX. In this paper, the interaction of LVFX and HSA has been studied fluorescence, UV, Fourier transform infrared (FT-IR) and molecular modeling method. The results indicated that LVFX induced the intrinsic fluorescence quenching of HSA though a static quenching procedure, and the effective binding constants (K(a)) were calculated to be 9.44 x 10(4) L x mol(-1) (294 K) and 2.74 x 10(4) L x mol(-1) (310 K) by used of the Stern-Volmer equation. According to the Vant's Hoff equation, the reaction was characterized by negative enthalpy (deltaH = -59.00 kJ x mol(-1)) and negative entropy (delta S = - 105.38 J x mol(-1) x K(-1)), indicated that the predominant forces in the LVFX-HSA complex were hydrogen bonding and van der Waals forces. By displacement measurements, the specific binding of LVFX in the vicinity of Site I of HSA was clarified. The binding distance of 3.66 nm between Trp214 and HSA was obtained by the Förster theory on resonance energy transfer. Furthermore, the binding details between LVFX and HSA were further confirmed by molecular docking studies, which were consistent with the experimental results. The alternations of protein secondary structure were calculated from FT-IR spectra. Upon formation of LVFX-HSA complexes, the amount of alpha-helical structures were decrease, but the numbers of beta-sheet structures, beta-turn structures and random structures were increase, respectively. This result indicated that LVFX induced unfolding of the polypeptides of HSA.

To study the transformation of Astragaloside IV in bidirectional solid fermenting of Astragalus membranaceus var. mongholicus.The chemical components of pre and post-fermenting were comparatively analyzed by techniques of HPLC, column chromatography and spectral identification. Antioxidant effect of transformational product on vascular endothelial cells was researched.In fermenting of Astragalus membranaceus, Astragaloside IV was transformed into 6-O-beta-D-glucoside cycloastragenol, which had significant antioxidant effect.Biotransformation of Astragaloside IV in Astragalus membranaceus was occurred after bidirectional solid fermenting with Ganoderma lucidum, and the biotransformation could enhance effect.

To investigate the impact of the drug resistance on the radioresistance in human pancreatic cancer cell lines.Three drug resistant pancreatic cancer cell sublines induced by fluorouracil (5-FU), adriamycin (ADM) and gemcitabine respectively, SW1990/FU, SW1990/ADM and SW1990/Gz, were tested for the cell cycle and radio-sensitivity with flow cytometry and clonogenic assay.Compared with SW1990, the cell cycle assay indicated higher G(0)/G(1) period percentage in SW1990/FU and SW1990/Gz, but the G(2)/M period percentage decreased; SW1990/FU had the same while SW1990/Gz had lower S period percentage. SW1990/ADM almost had a similar cell cycle with SW1990. Clonogenic assay showed both SW1990/FU and SW1990/Gz had greater survival fraction (SF(2)) than SW1990, but SW1990/ADM had seemingly similar SF(2) as SW1990.Drug resistant pancreatic cancer cell lines have reduced G(2)/M period percentage and increased radioresistance.

To establish a 5-fluorouracil (5-FU)-resistant pancreatic adenocarcinoma (PAC) cell strain, and to investigate its biological characteristics.The PAC cell strain SW1990 was selected into a multidrug-resistant cell strain stepwise with 5-FU, one of the most common drugs used in PAC chemotherapy, for 12 months and subsequently named SW1990/FU. The cell strain was characterized in terms of morphology, biology, and cross-resistance to adriamycin(ADM), mitomycin-C (MMC), and gemcitabine. BHLB/c-m nude mice tumor growth and CEA and CA19-9 levels were analyzed. In addition, karyotyping and FACS analysis were performed in SW1990/FU and SW1990.The SW1990/FU cell strain was 132.7 times more resistant to 5-FU than the parental SW1990 cells, and exhibited cross-resistance to other agents. Compared to the parental cells, SW1990/FU cells exhibited a smaller growth rate, delayed cell-doubling time, and specific changes in chromosomes 18. Tumor diameters in multidrug resistance and parental cells inoculated in in vivo experiments were (1.5 +/- 0.30) cm and (0.8 +/- 0.15) cm, respectively.Morphological adaptation and intracellular changes can be induced by drug challenge in PAC cells. SW1990/FU may be used as an experimental system for the search to overcome drug resistance and to elucidate possible mechanisms of acquired drug resistance in human pancreatic cancer.

The results are conflicting in detecting P-glycoprotein (P-gp) in pancreatic cancer. The aim of this study was to detect the expression of multidrug resistant gene 1 (MDR1) in pancreatic cancer cell lines.MDR1 mRNA and P-gp were detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical assay (IHC) in three pancreatic cancer cell lines SW1990, CAPAN-1 and P3. P-gp functions were evaluated through the rhodamine extrusion test.Two of the three cell lines expressed MDR1 positively at different levels. The rhodamine extrusion test showed that the percentage of positive cells in MDR(+) cells was significantly lower than that in MDR1(-) cells. The results of IHC, RT-PCR and the rhodamine extrusion test were consistent with each other.All of these methods are reliable in the detection of MDR1 in pancreatic cancer tissue, thus providing a guide for clinical chemotherapy of pancreatic cancer.

A novel multi-components microcapsule--SA/CS-CaCl2/PMCG system was introduced. The effects of PMCG and SA/CS-CaCl2/PMCG microcapsules on the growth of free E. coli and Saccharomyces cerevisiae were studied respectively. In addition, the growth of immobilized E. coli and Saccharomyces cerevisiae were also investigated. The results showed that: Just like other synthetic polycations, PMCG above certain concentration (0.5%) strongly inhibited the growth of free E. coli and Saccharomyces cerevisiae, but SA/CS-CaCl2/PMCG microcapsules almost had no effects on their growth and on the consumption of glucose concentration by Saccharomyces cerevisiae. What's more, immobilized E. coli and Saccharomyces cerevisiae grew almost as normally as free cultivation. As a whole, SA/CS-CaCl2/PMCG microcapsules had good biocompatiability and can be used as a new immobilization system.

One of the major limitations of curative resection in the patients with pancreatic cancer is local tumor extension to the major vessels surrounding pancreas. Therefore the assessment of the involvement of major arteries surrounding pancreas by tumor before operation is very important for the judgement of respectability of pancreatic carcinoma. This study was designed to assess the clinical value of contrast-enhanced CT(CECT) and selective angiography (SAG) in predicting the unresectability of patients with pancreatic cancer.From Aug 7, 1996 to Aug 12, 2000, 67 patients with pancreatic ductal adenocarcinoma proved pathologically were retrospectively analyzed. Of these patients, 31 and 54 patients were treated with CECT and SAG, respectively. The involvement of major vessels surrounding pancreas in CECT and SAG were assessed by operator according to specific criterias, which were compared with finding in operation. Finally, the accuracy of the method was assessed.Among 31 cases who were treated with CECT, 13 were judged unresectable by CECT; and 12 were found unresectable during operation, with predict value of 91%. Among 54 cases who were treated with SAG, 28 were judged unresectable by SAG; and 23 were found unresectable during operation, with predict value of 82%. The sensitivity, specificity, and predict value of CECT and SAG were 60%, 91%, 92%, and 77%, 79%, 82%, respectively. The sensitivity, specificity, and predict value of CECT combined with SAG were 91%, 100%, 100%, respectively.Enhanced CT and SAG are useful in assessing the unresectability of pancreatic carcinoma, the combination of two ways can improve the sensitivity, specificity and predict value.