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Abstract Background Amplification of the ERBB2 (Her-2/neu) oncogene, which occurs in approximately 25% of breast carcinomas, is a known negative prognostic factor. Available data indicate that a variable number of nearby genes on chromosome 17q may be co-amplified or deleted, forming a continuous amplicon of variable size. In approximately 25% of these patients, the amplicon extends to the gene for topoisomerase II alpha (TOP2A), a target for anthracyclines. We sought to understand the significance of these associated genomic changes for breast cancer prognosis and predicting response to therapy. Methods and patients Archival tissue samples from 63 breast cancer patients with ERBB2 amplification, stages 0–IV, were previously analyzed with FISH probes for genes located near ERBB2. In the present study, the clinical outcome data were determined for all patients presenting at stages I–III for whom adequate clinical follow up was available. Results Four amplicon patterns (Classes) were identified. These were significantly associated with the clinical outcome, specifically, recurrence of breast cancer. The Amplicon class IV with deleted TOP2A had 67% (6/9) cases with recurrence, whereas the other three classes combined had only 12% (3/25) cases (p-value = 0.004) at the time of last follow-up. TOP2A deletion was also significantly associated with time to recurrence (p-value = 0.0002). After adjusting for age in Cox regression analysis, the association between TOP2A deletion and time to recurrence remains strongly significant (p-value = 0.002) whereas the association with survival is marginally significant (p-value = 0.06). Conclusion TOP2A deletion is associated with poor prognosis in ERBB2-amplified breast carcinomas. Clarification of the mechanism of this association will require additional study.

Opioids exert analgesic effects by agonizing opioid receptors and activating signaling pathways coupled to receptors such as G-protein and/or β-arrestin. Concomitant respiratory depression (RD) is a common clinical problem, and improvement of RD is usually achieved with specific antagonists such as naloxone; however, naloxone antagonizes opioid analgesia and may produce more unknown adverse effects. In recent years, researchers have used various methods to isolate opioid receptor-mediated analgesia and RD, with the aim of preserving opioid analgesia while attenuating RD. At present, the focus is mainly on the development of new opioids with weak respiratory inhibition or the use of non-opioid drugs to stimulate breathing. This review reports recent advances in novel opioid agents, such as mixed opioid receptor agonists, peripheral selective opioid receptor agonists, opioid receptor splice variant agonists, biased opioid receptor agonists, and allosteric modulators of opioid receptors, as well as in non-opioid agents, such as AMPA receptor modulators, 5-hydroxytryptamine receptor agonists, phosphodiesterase-4 inhibitors, and nicotinic acetylcholine receptor agonists., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Shima River catchment is of strategic importance to urban water supply in Dongjiang portable water source area. To investigate the hydro-chemical characteristics of Shima River, 39 river water samples were collected in February, June and November, 2012 to analyze the major ions (K+, Na+, Ca2+, Mg2+, Cl-, SO4(2-) , HCO3-) and nutritive salts (PO4(3-), NO3- and NH4+) and to discuss the temporal-spatial variation and controlling factors of hydro-chemical composition, relative sources identification of varied ions was performed as well. The results showed that the hydro-chemical composition exhibited significant differences in different periods. The average concentration of total dissolved solid ( TDS) and nutritive salts in different investigated periods followed the decreasing order of November > February > June. The dominant anion of Shima River was HCO3-, and Na+ + K+ were the major cations in February and November which were changed to Ca2+ in June, the hydro-chemical types were determined as HCO(3-)-Na+ and HCO(3-)- Ca2+ in dry (February and November) and rainy (June) seasons, respectively. Spatial variations of concentration of nutritive salts were mainly affected by the discharges of N- and P-containing waste water resulted from human activities. The ratio between N and P of water sample (R7) was 18.4:1 which boosted the "crazy growth" of phytoplankton and led to severe eutrophication. According to Gibbs distribution of water samples, dissolution of hydatogenic rocks was the primary factor to control the major cations of river water in dry season, however, the hydro-chemical composition was significantly affected by the combination of hydatogenic and carbonate rocks in rainy season. The deposition of sea-salts contributed less to chemical substances in river. Correlation analysis revealed that K+, Na+, Mg2+, Cl- and SO4(2-) were partly derived from the application of fertilizer and the discharge of industrial effluent; Waste water of poultry feeding and sanitary wastewater transported large quantities of NH(4+)-N, PO4(3-)-P and NO(3-)-N into the river.

Objective: To evaluate the reliability and validity of musculoskeletal questionnaire., Methods: A self-administered modified musculoskeletal questionnaire was used to investigate 12 098 workers from eight occupations, i.e. coal mining, petroleum, metallurgical, mechanical manufacturing, chemical, garment and railroad transportation industries and education. The Cronbach's α coefficient, analysis of covariance and multiple logistic regression were used to assess the reliability and validity of musculoskeletal questionnaire., Results: The consistent test between total items of Musculoskeletal Questionnaire and each factor showed that the range of Cronbach's α was 0.52 ∼ 0.92, except from vibration factor, other Cronbach's α was more than 0.7. All 55 items of Musculoskeletal Questionnaire were subjected to factor analysis, and ten latent factors were identified, which explained 55.17% of the total variance. The potentially hazardous working conditions could be categorized into seven dimensions (force, dynamic load, static load, repetitive load, climate factors, vibration exposure and environmental ergonomic factor), which consisted with the theory model. The results of covariance analysis indicated that there were significant difference among 7 dimension indices in different jobs (P < 0.01)., Conclusion: The modified Musculoskeletal Questionnaire is a valid and reliable tool for measuring musculoskeletal workload.

Senescence-accelerated mouse prone 8 (SAMP8) has an early onset of senility and a shorter life span, providing with cognitive impairment. Contrasted with C57BL/6 mouse, which is most commonly used in the study of Parkinson's disease (PD), SAMP8 needs shorter period of breeding and might be good candidate for the investigation of cognitive impairment in PD. Studies had shown the increase of sensibility to 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) with aging in C57BL/6 mouse. However, the sensitivity of MPTP neurotoxicity depends on the strains of animal and the exact mechanisms of the progression of PD promoted by aging is lack of consensus. Here, we showed after MPTP injection, the spontaneous activity of both young (3-month-old) and old (6-month-old) SAMP8 decreased dramatically, and the old mice required longer recovery time. Immunohistochemical and immunoblot analysis revealed that old mice displayed significant reductions in the dopaminergic neuron numbers and tyrosine hydroxylase (TH) protein. Microglia protein (CD11b) in the striatum of old mice increased more pronouncedly than that in the young mice from 24 h to 3 days. Inducible nitric oxide synthase (iNOS) in the striatum remarkably increased, however, no discernible difference between the two groups was found. These results suggested that the sensibility to MPTP increased with aging in SAMP8. A greater increase of microglial activation in old mice may be a possible mechanism to explain how advancing age predisposes the dopamine system to parkinsonism. The MPTP-SAMP8 model will start a new consideration for the study of PD., (Copyright 2010 Elsevier B.V. All rights reserved.)

Interindividual variability of cytochrome P450 (CYP) 3A inhibition by grapefruit juice was investigated in relation to CYP3A5 and multidrug resistance gene (MDR) 1 genetic polymorphisms in Chinese Han, Uygur, and Kazakh healthy subjects. The measurement of urinary 6 beta-hydroxycortisol/cortisol ratio was used to evaluate CYP3A activity in vivo by high-performance liquid chromatography. CYP3A5*3 and MDR1 C1236T, G2677T/A, and C3435T polymorphisms were analyzed by polymerase chain reaction restriction fragment length polymorphism. After grapefruit juice intake, urinary ratios significantly decreased in 3 Chinese ethnic groups (P < .001). Kazakh had a larger decrease of urinary ratio compared to that of Han (P < .05), and the latter had similar decrease with Uygur. Furthermore, Chinese healthy subjects carrying CYP3A5*3/*3 and MDR1(1236-2677-3435) T-T-T/T-T-T genotypes were found to have the largest reduction of urinary ratio (mean, 61.4%; 95% confidence interval, 53.4%-69.5%), whereas *1/*3 subjects carrying MDR1(1236-2677-3435) C-G-C/C-G-C genotypes had the lowest reduction (mean, 25.9%; 95% confidence interval, 3.1%-48.8%; P < .01). In conclusion, both CYP3A5*3 and MDR1 variants influenced the extent of CYP3A inhibition by grapefruit juice in Chinese healthy subjects. The genetic variations influencing the CYP3A inhibitive phenotype might be helpful to explain the individual variability of grapefruit juice-drug interactions.

Campylobacter jejuni is the most common zoonotic bacterium associated with human diarrhea, and chickens are considered to be one of the most important sources for human infection, with no effective prophylactic treatment available. We describe here a prophylactic strategy using chitosan-DNA intranasal immunization to induce specific immune responses. The chitosan used for intranasal administration is a natural mucus absorption enhancer, which results in transgenic DNA expression in chicken nasopharynx. Chickens immunized with chitosan-DNA nanoparticles, which carried a gene for the major structural protein FlaA, produced significantly increased levels of serum anti-Campylobacter jejuni IgG and intestinal mucosal antibody (IgA), compared to those treated with chitosan-DNA (pCAGGS). Chitosan-pCAGGS-flaA intranasal immunization induced reductions of bacterial expellation by 2-3 log(10) and 2 log(10) in large intestine and cecum of chickens, respectively, when administered with the isolated C. jejuni strain. This study demonstrated that intranasal delivery of chitosan-DNA vaccine successfully induced effective immune response and might be a promising vaccine candidate against C. jejuni infection.

Objective: To prepare a platinum microcoil coated with polymers and vascular endothelial growth factor (VEGF), and evaluate its surface characteristics and property of sustained VEGF release., Methods: The surface of the platinum microcoils (GDC) were modified by coating P(DLLA-co-TMC) copolymer and immobilizing heparin on the surface of GDC. VEGF was then loaded onto the surface of GDC and the controlled release of VEGF within GDC was achieved. The morphology was observed by scanning electron microscope, and the sustained release of VEGF was evaluated by enzyme-linked immunosorbent assay (ELISA)., Results: Platinum coils were prepared by successive deposition of P(DLLA-co-TMC) copolymer and anionic heparin, and VEGF was immobilized through affinity interaction with heparin. The accumulative release of VEGF increased obviously during the entire testing period without burst release., Conclusion: The use of P(DLLA-co-TMC) copolymer allows immobilization of VEGF on the platinum coils for controlled VEGF release, and improves the biological property of the coils.

CYP2C19 and CYP2E1 show great genetic differences between Orientals and Caucasians. The objective of this study was to investigate the genotype and allele distribution patterns of CYP2C19 and CYP2E1 polymorphisms among healthy participants in mainland Chinese Kazakh, Uygur and Han populations by the PCR-restriction fragment length polymorphism technique. The allele frequencies of CYP2C19 2, CYP2E1 5B and CYP2E1 6 were significantly lower in the Chinese Kazakh (15.4, 11.2 and 14.5%, respectively) (P<0.05) and Uygur (16.1, 12.1 and 18.8%) (P<0.05) populations than that in the Chinese Han population (28.8, 19.4 and 26.2%), but the frequencies of CYP2C19 3 were similar among the three populations (8.0, 9.4 and 7.2%). Frequencies of the three combined genotypes, one for predicted CYP2C19 poor metabolizers and two for predicted high levels of CYP2E1 transcription, were significantly lower in the Chinese Kazakh (7.5, 19.6 and 28.0%, respectively) (P<0.05, chi(2)-test) and Uygur (8.1, 22.8 and 33.6%) (P<0.05) populations compared with the Chinese Han population (16.5, 35.9 and 44.7%). The present research shows that frequencies of the functional single-nucleotide polymorphisms in the CYP2C19 and CYP2E1 genes vary in the Chinese Kazakh, Uygur and Han populations, suggesting that disease susceptibilities or drug responses associated with enzyme activities of CYP2C19 and CYP2E1 may differ in the diverse ethnic populations in mainland China.

Neuroprotective effects of enriched environment (EE) have been well established. Recent study suggests that exposure to EE can protect dopaminergic neurons against MPTP-induced Parkinsonism. After 64 female SAMP8 mice were reared in EE and standard environment (SE) for 3 months, the effects of EE and SE were compared on behavioural change, tyrosine hydroxylase (TH) immunoreaction positive neuron and dopaminetransporter (DAT) expression in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-treated SAMP8. EE mice showed decreased spontaneous activity compared with SE mice. But EE+MPTP mice showed less decreased spontaneous activity compared with SE+MPTP mice. Otherwise, EE mice showed increased percentage of entries into the open arms and percentage of time spent in the open arms. Furthermore, EE mice demonstrated reduced neurotoxicity, with less decreased TH mRNA and protein expression in Substantia Nigra (SN) after MPTP administration compared with SE mice. SE mice showed a 53.77% loss of TH-positive neurons, whereas EE mice only showed a 42.28% loss. Moreover, EE mice showed decreased DAT mRNA and protein expression compared with SE mice. These data demonstrate that EE can protect dopaminergic neurons against MPTP-induced neuronal damage, which suggest that the probability of developing Parkinson's disease (PD) may be related to life environment.

Specifying the chemical environment of cells is a well-established method of controlling cellular behaviors. In this study, poly(ethylene terephthalate) (PET) film was selected as a typical biomaterial to detect the effects of chemical modifications on material surface in controlling cell behaviors. Natural biopolymer chitosan and its biocompatible derivative, O-carboxymethylchitosan (OCMCS) were surface immobilized on PET, respectively, via argon plasma followed by graft copolymerization with acrylic acid (AAc), which was exploited to covalently couple PET with chitosan (CS) and OCMCS molecules. Smooth muscle cells (SMCs) displayed a surface-dependent cell spreading and cytoskeletal organization. The cells spread with a more pronounced elongated spindle shape, smaller cell area, and lower cell shape index (CSI) on OCMCS-modified PET surface than on PET, or the PAA and chitosan-immobilized PET surfaces after 24 h of culture. Cell-culture viability after 5 days showed that all the modified materials possessed good cell proliferation. Our results suggest that cell adhesion, morphology, and growth can be mediated not only by varying the functional groups, electric charge, and wettability of PET surface but also by the specific biological recognition elicited from the biomaterials. These findings strongly support the concept that the microenvironment significantly influences cell behavior, highlighting the importance of environmental material biochemistry in cell-based tissue engineering schemes.

It was found that in buffer solution of pH 7.0, the addition of sodium dodecyl sulfate (SDS) to the solution of phenothiazine drugs, such as chlorpromazine, promethazine and trifluoperazine, showed a remarkable enhancement of their fluorescence intensity. A further study proved that the phenothiazine drugs can be determined by fluorophotometric method in micellar system. Under optimal conditions, there was a good linear relationship between fluorescence intensity and phenothiazine compounds concentration, and the detection limit of 3.0 x 10(-8) M chlorpromazine, 3.0 x 10(-8) M promethazine and 1.5 x 10(-8) M trifluoperazine (S/N=3) were also obtained. This method has been used to determine phenothiazine drugs in tablets with satisfactory results.

The poor mechanical strength and vasoactivity of current small-diameter tissue engineered blood vessels (TEBVs) remain unsolved problems. Given the plasticity of smooth muscle cells (SMCs), 1 of the main limitations of current scaffolding techniques is the difficulty in controlling SMC phenotype shifts in vitro. A synthetic phenotype allows the cells to rapidly proliferate and produce extracellular matrix (ECM), whereas a shift to contractile phenotype with organized ECM ultimately provides a functional blood vessel. In this study, 3D deep (65 microm) and wide microchannels separated by high-aspect ratio (8) microwalls were successfully ultraviolet (UV) microembossed using a liquid UV polymerizable biodegradable macromer (poly(epsilon-caprolactone-r-L-lactide-r-glycolide) diacrylate) and the in vitro guidance effects of varying channel width (40-160 microm) on SMCs were verified. The results show that SMCs cultured in the wider microchannels (80-160 microm wide) switch from fibroblast morphology and random orientation to spindle-shaped morphology, and align along the direction of the microchannel nearing confluence achieved with similar cell density to unpatterned film. Further, an enhanced expression of smooth muscle alpha-actin of SMCs grown on micropatterns was found nearing confluence, which demonstrates a phenotype shift to a more contractile phenotype. These films are flexible and can be folded into tubular and lamellar structures for tissue engineering of small-diameter TEBVs as well as other organs such as esophagus or intestine. These results suggest that these micropatterned synthetic biodegradable scaffolds may be useful for guiding SMCs to grow into functional, small-diameter vascular grafts.

A simple and effective method of biomacromolecule immobilization on biomaterial surface for direct tuning of biophysical parameters such as the initial cell deformation rate, degree of cell spreading and adhesion kinetics is important for tissue engineering. The photochemical immobilization of azide-chitosan (Az-CS) on poly (lactide-co-glycolide) acid (PLGA) is applied here. Chitosan immobilization on PLGA through the photoactive azide group further facilitates subsequent grafting of other biocompatible biomacromolecules like gelatin (Gel) through the active amine groups on CS. This study quantitatively compares the 3T3 fibroblast adhesion dynamics on three PLGA surfaces (Gel-CS-PLGA, CS-PLGA and unmodified PLGA surfaces) using Confocal-Reflectance Interference Contrast Microscopy (C-RICM) together with phase contrast imaging. CS-PLGA and Gel-CS-PLGA surfaces developed were confirmed by X-ray photoelectron spectroscopy, atomic force microscopy and water contact angle and cell adhesion contact dynamics measurements. The cell adhesion was strongest on the Gel-CS-PLGA surface and lowest on unmodified PLGA. The steady state adhesion energy attained by the cells on gelatin modified PLGA surface is determined as 4.0 x 10(-8) J/m(2), which is about 400 times higher than that on PLGA surface (1.1 x 10(-10) J/m(2)). Significantly increased cell adhesion with Gel-CS-PLGA is postulated to result in increased cell spreading. Our integrated biophysical method can quantify the transient contact dynamics and is sufficiently accurate to discriminate even between Gel and CS modified surfaces.

Foldable hydrogel films with micropatterns measuring 480 microm by 45 microm by 54 microm by 2 cm (width of microchannel by width of microwall by height of wall by length of pattern) were made by UV embossing of a block copolymer of polycaprolactone (PCL) and poly(ethylene glycol) (PEG), specifically PCL-b-PEG-b-PCL-diacrylate (DA), with a polydimethylsiloxane mold. The mold was treated with Ar/CF(4) plasma to simultaneously promote microchannel filling and demolding, and the glass substrate was modified with 3-(trimethoxysilyl) propyl acrylate to promote hydrogel adhesion to avoid delamination of the gel during demolding. The micropatterned hydrogel film was detached from the glass substrate by freeze-drying. As the films were demolded, the microstructured pattern was well replicated in the hydrogel. The gel pattern dimensions shrank with freeze-drying and increased with water swelling, but under both conditions, the gel micropattern morphology was perfectly preserved. PCL-b-PEG-b-PCL-DA hydrogel was found to have good biocompatibility compared with PEGDA hydrogel. A micropattern with a smaller microchannel width of 50 microm was also made. Micropatterned foldable and biocompatible hydrogel films have potential applications in the construction of tissue-engineering scaffolds.

O-carboxylmethylchitosan (OCMCS), a chitosan derivative, has emerged as a strong polymeric biomembrane perturbant. In this study, the interaction between OCMCS and dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was examined with cross-polarization microscopy, differential scanning calorimetry (DSC) and the surface pressure-area isotherms techniques. Cross-polarized light images showed that OCMCS induced the fusion of small DPPC multilamellar vesicles (MLV) to form large lamellar structures. From DSC measurement, the highest degree of fusion was found at the optimum OCMCS concentrations between 0.0625 and 0.2 mg/ml which are orders of magnitude lower than those required for similar reductions with unmodified chitosan as perturbant. At these concentrations, the association of DPPC and OCMCS enhances the fusion of DPPC vesicles. Surface pressure-area isotherms of DPPC monolayer in the presence of OCMCS imply interactions between OCMCS and DPPC in neutral condition. In comparison with chitosan, OCMCS proved to be a more effective membrane perturbant not only in neutral but also in acidic and basic conditions. The physical driving forces for OCMCS-induced perturbation of DPPC bilayer in neutral conditions are mainly hydrogen bonding and hydrophobic interactions. In acidic or basic conditions, the physical driving forces are dominated by the electrostatic interactions. The strong OCMCS-DPPC interaction will potentially increase the effectiveness of OCMCS for gene or drug delivery.

Chitosan and O-carboxymethylchitosan (OCMCS) have been proved to have biocompatibility and have been extensively researched in the field of biomaterials. In this study, Confocal-reflectance interference contrast microscopy (C-RICM) in conjunction with phase contrast imaging was used to investigate the adhesion contact dynamics of 3T3 fibroblasts on chitoan and OCMCS surface-modified silica coverslips. The C-RICM results demonstrate that the weak cell contact forms on OCMCS surface while a much stronger contact area forms on the chitosan surface. 3T3 fibroblasts are found to spread randomly with spindlelike morphology on the chitosan surface, while they exhibit elongated morphology and align on the OCMCS surface. It is believed that fibroblast behaviors such as migration, spreading with an elongated morphology, and alignment on the OCMCS surface are correlated with the weak cell contact. The mechanisms to form cell adhesion contact on chitosan and OCMCS were discussed.

Chitosan-modified biodegradable hydrogels were prepared by UV irradiation of solutions in mild aqueous acidic media of poly(caprolactone)-co-poly(ethylene glycol)-co-poly(caprolactone) diacrylate (PCL-PEG-PCL-DA) and chitosan. Hydrogels obtained were characterized using FT-IR, DSC, TGA and XPS. FT-IR, TGA and DSC revealed the semi-interpenetrating polymer network structure formed in the hydrogel. Though the water swelling degree of these chitosan-modified hydrogels was substantial in the range of 322-539%, it was found that fibroblasts could still attach, spread and grow on them; this is in contrast to the commonly investigated PEG-diacrylate hydrogel. The MTT assay demonstrated that cells could grow better on 3 or 6% chitosan-modified hydrogel than unmodified PCL-PEG-PCL-DA hydrogels or low-content (1%) chitosan-modified PCL-PEG-PCL-DA hydrogel. Increased chitosan content resulted in increased cell interaction and also decreased water swelling, both of which results in increased cell attachment and spread.

Immobilization of the anticoagulative or antithrombogenic biomolecule has been considered as one of the important methods to improve the blood compatibility of artificial biomaterials. In this study, a novel immobilization reaction scheme was utilized to incorporate O-butyrylchitosan (OBCS) onto the activated glass surface with an aim to develop an anticoagulative substrate. Activation of the glass surface was carried out by silanization and then OBCS was grafted to the silanized surface via a radiation grafting technique. The OBCS-grafted glass surfaces were characterized by electron spectroscopy for chemical analysis (ESCA) and atomic force microscopy (AFM). The blood compatibility of the OBCS-grafted glass was evaluated by platelet rich plasma (PRP) contacting experiments and protein adsorption experiments in vitro. These results have demonstrated that the surface with immobilized OBCS shows much less platelet adhesive and fibrinogen adsorption compared to the control surface. Therefore, the novel reaction scheme proposed here is very promising for future development of an anticoagulative glass substrate.

For use in micro-patterned scaffolds in tissue engineering, novel diacrylated triblock macromers (PLA-b-PCL-b-PLA, PGA-b-PCL-b-PGA and PCL-b-PEO-b-PCL) were synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR) and gel permeation chromatography (GPC). All diacrylated polymers were designed as triblock copolymers and involved biodegradable blocks of relatively non-polar epsilon-caprolactone (CL) and polar monomers such as glycolide (GA), lactide (LA) or ethylene oxide (EO). All triblock polymers were prepared in molecular weights of a few kilo daltons via the anionic ring-opening polymerization (ROP) of the corresponding lactide, glycolide or caprolactone using stannous octoate [Sn(Oct)(2)] as catalyst. The polymers had low polydispersity indices, ranging from 1.23 to 1.56. Biodegradable polymeric networks were prepared with conversions of 72-84% via photopolymerization of the triblock diacrylated polymers with 2,2-dimethoxy-2-phenylacetophenone (DMPA) as photoinitiator. PLA-b-PCL-b-PLA copolymers crumbled easily and were not suitable for micro-patterning. PGA-b-PCL-b-PGA copolymers had higher water contact angles than PCL-b-PEO-b-PCL and were also cytocompatible with Fibroblasts 3T3.

Objective: This article reports a population genetic study on six short tandem repeat(STR) loci, D7S820, D19S253, D12S391, D5S818, D16S539 and D8S1179, in a sample of unrelated Chinese Han individuals(n=122-173) living in Hebei province., Methods: DNA extraction from blood samples (200 in number) and multiplex amplification of the above six loci were carried out. Using denaturing polyacrylamide gel electrophoresis and silver stain, the authors investigated the distribution of allele frequencies of the six loci in Han population in Hebei province., Results: The STR polymorphisms at all of the six loci were observed in Chinese Han population in Hebei province. The observed heterozygosities of D7S820, D19S253, D12S391, D5S818, D16S539 and D8S1179 were 0.828, 0.757, 0.769, 0.837, 0.785 and 0.852, respectively. The measured values of the power of discrimination (PD) were 0.914, 0.919, 0.940, 0.909, 0.917, 0.944; of the mean exclusion chance(MEC) 0.618, 0.740, 0.801, 0.557, 0.655, 0.696 and of the polymorphism information content (PIC) in Chinese 0.771, 0.760, 0.762, 0.708, 0.776 and 0.794, respectively., Conclusion: The genotype distributions of the six STR were in accordance with Hardy-Weinberg equilibrium. The numerical values of the PD and MEC are relatively high in Hebei province, and thus can be of significant application in population genetics and forensic medicine.

Novel silica-butyrylchitosan hybrid biomaterials were produced by a sol-gel technique, using butyrylchitosan as the organic species incorporated into the silicon alkoxide (TEOS) based network. 3-acryloxypropyl trimethoxysilane (MPTMS) was used effectively to combine the organic and inorganic species to form uniform hybrid biomaterials. All the samples made were in the form of thin, flexible films with transparent clarity. The blood-clotting and platelet adhesion assay confirmed that these hybrid biomaterials displayed potential good blood compatibility.

The chitosan/PHEA-blended hydrogels were prepared from PHEA and chitosan in various blend ratios. The water contents of the hydrogels were in the range of 50%-80% (wt). The attachment and growth of fibroblast cells(L929) on the hydrogels were studied. The results indicated the PHEA content in hydrogels has great effect on cell attachment but has little effect on the growth of L929 cells.

Objective: To discuss the approaches of tissue engineered blood vessels (TEBV) reconstruction., Methods: The recent literatures about TEBV were widely reviewed. We summarized various types of biomaterials served as scaffold for TEBV and evaluated the construction model of TEBV. And the biological properties of some TEBV were compared., Results: Although the final model of construction of TEBV was not clear, reports in the last two years had shown several important advances in this exciting field., Conclusion: Mimicry of some or all of the properties of three layers of natural healthy blood vessels has been the strategy of all TEBV approaches.

A clinical trial was conducted in order to evaluate the therapeutic effect and side effects of low-dose all-trans retinoic acid (ATRA) in the treatment of acute promyelocytic leukemia (APL). First of all, we compared the pharmacokinetic features in normal individuals with a single oral dose of ATRA at 15 mg/m2 and 45 mg/m2, respectively. The results showed that maximal plasma concentration with oral ATRA at 15 mg/m2 was high enough (10(-6) mol/L) to induce APL cell differentiation. Based on these results, 27 cases of de novo APL patients were treated with oral ATRA at a dose of 15-20 mg/m2/day and 24 of the 26 (92%) evaluable cases achieved clinical complete remission (CR) after 13 to 67 dyas of ATRA treatment. No patient experienced retinoic acid syndrome (RAS) and DIC. The Cmax with a single dose of ATRA on day 1 of treatment and immediately after obtaining of CR with ATRA in three cases demonstrated similar values in one patient and an about 2 fold decrease in two patients. Moreover comparison with a relatively well-matched previous group of 20 APL patients treated with high-dose ATRA showed that low-dose ATRA is as effective as high-dose in treating APL patients and may provide the advantages of decrease of the degree of hyperleukocytosis and side effects.