Structural variations of rice starch affected by constant power microwave treatment.

Although lots of work has reported the structural variations of starch in microwave treatment, most of them are detected in the environment with non-constant microwave power and inhomogeneous heating, and the results are always in poor repeatability. In this study, the equipment with constant microwave power (CPM) and homogeneous heating was designed. And the phase transition of multi-scale structure of rice starch (30% moisture content) caused by CPM treatments with two heating modes, namely rapid microwave heating (RWH) and slow microwave heating (SWH) were investigated systematically. SEM results showed that the surface of starch granules after CPM treatment were rough and broken, and the damage caused by RWH was more distinct than that by SWH. SAXS, XRD and 13C NMR results revealed that the CPM treatment decreased the degree of crystallinity and content of double helices of starch. Moreover, the influence of RWH on the variation of starch granules was greater than that of SWH, which can be attributed to the intensive friction and collision as well as the rapid evaporation of water in RWH treatment. Specifically, it exhibited greater destruction on the linkage of starch and the internal crystalline region in RWH treatment than SWH treatment, thereby resulting in more obvious damages on the lamellar and morphological structure of rice starch. In conclusion, CPM equipment has improved the problems of uneven heating and poor experimental repeatability. After CPM treated starch, the molecular structure of starch was destroyed, which provides a useful method to modify properties of starch.

[Attenuated total reflection-fourier transform infrared spectroscopic study of dried shark fin products].

Sixty-four pieces of shark fin dried products (including real, fake and artificial shark fin products) and real products coated with gelatin were rapidly and nondestructively analyzed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The characteristic of IR spectrograms among the above four kinds of samples were systematically studied and comparied, the results showed that the spectrograms of the same kind of samples were repeatable, and different kinds of shark fin products presented significant differences in the spectrograms, which mainly manifested as the specific absorption peaks of amido bonds in protein (1650, 1544 cm(-1)) and skeletal vibration in polysaccharide (1050 cm(-1)). The spectrograms of real shark fins were characterized by the strong absorption peaks of protein characteristic amide I and II absorbent (1650, 1544 cm(-1)) and relatively weak C--O--C vibration absorbent (1050 cm(-1)) owing to the high content of protein and relatively low level of polysaccharide. For fake shark fin products that were molded form by mixing together with the offcut of shark, collagen and other substances, the introduction of non-protein materials leaded to the weaker amido bonds absorbent than real products along with a 30 cm(-1) blue shift of amide I absorbent. Opposite to the real sample, the relatively strong absorption peak of polysaccharide (approximately 1047 cm(-1)) and barely existed amide absorbent were the key features of the spectrogram of artificial samples, which was synthersized by polysaccharide like sodium alginate. Real samples coated with gelatin, the peak strength of protein and polysaccharide were decreased simultaneously when the data collection was taken at the surface of sample, while the spectrogram presented no significant difference to real samples when the data was collected in the section. The results above indicated that by analyzing the characteristic of IR spectrograms and the value range of Apro/Apol collected by ATR-FTIR method could perform the undamaged and rapid identification for shark fins.

[Association between single nucleotide polymorphisms in Wnk1 gene and ischemic stroke in Chinese Han population].

OBJECTIVE: To investigate the association between single nucleotide polymorphisms (SNPs) in Wnk1 gene and ischemic stroke in Chinese Han population. METHODS: A hospital-based case-control study was carried out. The ischemic stroke group included 294 Chinese Han subjects, who were admitted with non-fatal ischemic stroke in departments of neurology of 5 hospitals in Xinjiang during January 2008 through December 2009. Control group included 314 age and sex-matched Han subjects without an inquired history of stroke, hospitalized in departments of surgery of these 5 hospitals. Ten tagging SNPs (tSNPs) of the Wnk1 gene were genotyped, and the association between these tSNPs and ischemic stroke were evaluated. The tSNPs (rs3858703, rs11611246, rs7305065, rs1990021, rs34408667, rs12309274, rs1012729, rs956868, rs12828016 and rs953361) were determined by the Multiplex SNaPshot platform. The data were analyzed by using t-test, Ξ2-test and logistic regression. Linkage disequilibrium and haplotype were analyzed by Haploview software. RESULTS: The rates of alcohol drinking, hypertension ,diabetes and hyperlipidemia in ischemic stroke group were higher than those in control group (37.1% vs 21.0%, 62.9% vs 36.6%, 18.0% vs 6.1% and 36.4% vs 17.5%, respectively, all P<0.01). No significant difference in smoking rate was found between two groups. The genotyping loss rates of all sites were less than 1%. All the tSNPs were examined by Hardy-Weinberg equilibrium test except rs34408667. tSNP rs11611246 in the 4th intron of the Wnk1 gene was significantly associated with ischemic stroke. The distribution frequency of T allele in cases was significantly lower than that in male controls (30.3% vs 35.7%, P =0.046). When the samples were further stratified according to gender, rs11611246 was found to be associated with a reduced risk of ischemic stroke in male cases than in controls. GT and TT genotype frequencies were 43.3% and 7.2% in male cases, 43.1% and 15.2% in male controls, respectively (P=0.038). The T allele was associated with a reduced risk of ischemic stroke, with a per-allele OR of 0.702(95%CI:0.517-0.953, P=0.023) in male cases than in male controls. The significance remained after adjusting the covariates of age (P=0.022), or the covariates of age, BMI, cigarette smoking, alcohol drinking, hypertension, diabetes and hyperlipidemia (P=0.008). No association between other 9 tSNPs and ischemic stroke was noted in Chinese Han subjects. CONCLUSION: The polymorphism of rs11611246 on the 4th intron of Wnk1 gene is associated with a reduced risk of ischemic stroke in Chinese Han population and the T allele might be a protective factor for ischemic stroke in male Chinese Hans.

Primary intracranial and spinal hydatidosis: a retrospective study of 21 cases.

OBJECTIVE: To analyse the epidemiological characteristics, clinical symptoms, radiological aspects, treatments, and outcomes of primary central nervous system (CNS) hydatidosis and compare our results with those observed for secondary intracranial hydatidosis. PATIENTS AND METHODS: We retrospectively reviewed 21 cases of primary CNS hydatid cysts operated on at the First Affiliated Hospital of Xinjiang Medical University between 1996 and 2010. RESULTS: Of the 21 primary cases, the vast majority were intracranial hydatidosis patients (20 cases, 95·24%). Only one patient had spinal hydatidosis. Unlike previously published reports, we found that intracranial hydatid cysts were more common in adults (80·96%) than in children (19·04%), with a slight male predominance (M/F = 1·1). All symptoms, including vomiting, nausea, and focal neurological signs, resulted from the increased intracranial pressure, which was closely associated with the cyst location. For the spinal hydatidosis patient, the primary symptom of back pain was indicative of spinal cord compression syndrome. All cysts in the 21 primary cases were pathologically similar. The recurrence percentage was 28% over 12 years. Two patients with multiple intracranial hydatid cysts died due to foramen magnum herniation. CONCLUSION: Despite imaging and therapeutic advances, CNS hydatidosis remains difficult to treat, and severe complications and the high incidence of recurrence result in unsatisfactory outcomes.

[Preparation and biological characteristics of a new doxorubicin-gelatin-microspheres for hepatic artery embolization].

OBJECTIVE: To prepare a new doxorubicin-gelatin-microspheres (DR-GMs) suitable for hepatic artery chemoembolization. METHODS: Oxidized dextran and glutaraldehyde were used respectively as crosslinking agent for preparing DR-GMs. Orthogonal design was employed to optimize the preparation of the oxidized dextran cross-linked GMs. The morphology, swelling, and in vitro and in vivo degrading were compared between the two groups of microspheres, both with 60% degree of cross-linking. RESULTS: The granulometers of both groups of microspheres fitted for hepatic artery embolization. The roundness of the microspheres (observed with scanning electron microscope) crosslinked by oxidized-dextran was better than those crosslinked by glutaraldehyde. The microspheres crosslinked by oxidized-dextran had an average diameter of (78.2 +/- 8.1) microm, and a narrow size distribution (76.4 +/- 3.2)%, which ranged from 50 to 125 microm. The drug content rate and encapsulation rate of the microspheres crosslinked by oxidized-dextran were (87.5 +/- 0.9)% and (12.2 +/- 1.1)% respectively, higher than those crosslinked by glutaraldehyde (P < 0.01). The cumulative release rate of doxorubicin from the microspheres crosslinked by oxidized-dextran in 12 hours was 83.2%, lower than that from the microspheres crosslinked by glutaraldehyde (P < 0.01). The in vitro and in vivo studies found that the duration of degradation of the microspheres crosslinked by oxidized-dextran appeared longer than those crosslinked by glutaraldehyde. CONCLUSION: Oxidized-dextran is a better crosslinking agent for preparing DR-GMs, because it has more advantages over glutaraldehyde as for hepatic artery chemoembolization.

Direct in vivo injection of 131I-GMS and its distribution and excretion in rabbit.

AIM: To explore the distribution and metabolism of (131)I-gelatin microspheres ((131)I-GMSs) in rabbits after direct injection into rabbits' livers. METHODS: Twenty-eight healthy New Zealand rabbits were divided into seven groups, with four rabbits per group. Each rabbit's hepatic lobes were directly injected with 41.336 +/- 5.106 MBq (131)I-GMSs. Each day after (131)I-GMSs administration, 4 rabbits were randomly selected, and 250 microL of serum was collected for gamma count. Hepatic and thyroid functions were tested on days 1, 4, 8, 16, 24, 32, 48 and 64 after (131)I-GMSs administration. Single-photon emission computed tomography (SPECT) was taken for each group on days 0, 1, 4, 8, 16, 24, 32, 48, 64 after (131)I-GMSs administration. A group of rabbits were sacrificed respectively on days 1, 4, 16, 24, 32, 48, 64 after (131)I-GMSs administration. Their livers were taken out for histological examination. RESULTS: After (131)I-GMSs administration, the nuclide was collected in the hepatic area with microspheres. The radiation could be detected on day 48 after (131)I-GMSs administration, and radiography could be seen in thyroid areas in SPECT on days 4, 8, 16 and 24. One day after (131)I-GMSs administration, the liver function was damaged but recovered 4 d later. Eight days after (131)I-GMSs administration, the levels of free triiodothyronine and free thyroxin were reduced, which restored to normal levels on day 16. Histological examination showed that the microspheres were degraded to different degrees at 24, 32 and 48 d after (131)I-GMSs administration. The surrounding parts of injection points were in fibrous sheathing. No microspheres were detected in histological examination on day 64 after (131)I-GMSs administration. CONCLUSION: Direct in vivo injection of (131)I-GMSs is safe in rabbits. It may be a promising method for treatment of malignant tumors.

Proapoptotic and pronecrosis effect of different truncated hepatitis C virus core proteins.

OBJECTIVE: To study the roles of different truncated hepatitis C virus (HCV) core proteins (CORE) in the pathogenesis of HCV persistent infection and hepatocellular carcinoma (HCC) and to assess intracellular localization in transiently transfected cells. METHODS: Seven truncated GFP (green fluorescent protein)-CORE fusion protein expression plasmids were constructed, which contained HCV CORE sequences derived from tumor tissues (BT) and non-tumor tissues (BNT) from one patient infected with HCV. Amino acid (aa) lengths were BT: 1-172 aa, 1-126 aa, 1-58 aa, 59-126 aa, 127-172 aa; BNT: 1-172 aa and C191: 1-172 aa respectively. Subcellular localization of CORE-GFP was analyzed by con-focal laser scanning microscope. Apoptosis and necrosis were quantified by flow cytometry. RESULTS: Different truncated CORE-GFP localized mainly in the cytoplasm, but nuclear staining was also observed. HCV CORE could induce apoptosis and necrosis, and different truncated COREs could induce cell apoptosis and necrosis at different levels. Among the same length 1-172 aa of BT, BNT and C191, the cell apoptosis and necrosis percentage of BT is highest, and C191 is the lowest (BT>BNT>C191). To the different fragment COREs of BT, N-terminal of CORE induced apoptosis and necrosis higher, compared with that of C-terminal (1-172 aa>1-126 aa>1-58 aa>127-172 aa>59-126 aa). CONCLUSION: These results suggest HCV CORE could induce apoptosis and necrosis of cells, which might play an important role in the pathogenesis of HCV persistent infection and HCC and the different CORE domains of different HCV quasi-species might have some difference in their pathogenesis.