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Single-crystal structures of the best high-temperature trichromatic blue azo dye C.I. Disperse Blue 148 and its diazonium component 3-amino-5-nitro-[2,1]- benzisothiazole are described herein. C.I. Disperse Blue 148 exhibits an essentially coplanar molecular structure and a dimeric packing mode between adjacent phenyl and benzisothiazole rings. Particularly, PXRD measurement reveals the existence of a new crystalline form of C.I. Disperse Blue 148 having the highest melting point and the best thermal stability, which is obviously different from all the known α, β, and γ forms. A one-phase recrystallization method, which can guarantee the complete transformation, is used to prepare the new crystalline form instead of the conventional heating of an aqueous suspension of α form. Furthermore, TGA–DSC and pH titration experiments have been carried out to reveal the thermal and pH stabilities of this heterocyclic dye. To our knowledge, this is the first structural example on benzisothiazole involved azo dyes.

Mucolipidosis II alpha/beta (ML II alpha/beta; I-cell disease) is a rare, inherited, metabolic disease and has often been clinically misdiagnosed. ML II alpha/beta results from a deficiency of the enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-PT), which causes the lysosomal enzymes to accumulate in plasma. We identified two new Chinese patients with ML II alpha/beta by lysosomal enzyme assay. Using targeted next-generation sequencing genetic analysis, we located two homozygous nonsense mutations in the GNPTAB gene, c.1071G>A (p.W357X) and c.1090C>T (p.R364X). These results were confirmed by Sanger sequencing. To our knowledge, the c.1071G>A mutation has not been previously reported. Our findings add to the number of reported cases of this rare illness and to the GNPTAB pathogenic mutation database. This work also demonstrates the application of lysosomal enzyme assay and targeted next-generation sequencing for the genetic screening analysis and diagnosis of ML II alpha/beta.

Three pairs of heterocyclic azo dyes and their corresponding Schiff bases were prepared by diazotization and Schiff-base condensation reactions between substituted 2-aminobenzothiazoles and either 3-(diethylamino)phenol or 3,5-dichloro-2-hydroxybenzaldehyde in order to obtain some high performance Disperse Red dyes and compare the structural and spectral differences between the azo dyes and Schiff bases. All azo dyes and Schiff bases in this work have the same benzothiazole/phenol skeleton but different substituent group in the phenyl ring. X-ray single-crystal diffraction analyses of selected compounds reveal that they have a similar planar conformation between the benzothiazole and phenol units but dissimilar dimeric crystal packing. Electronic spectra of the dyes demonstrate that the presence of N N and C N double bond chromophore units as well as substituent effects of different auxochrome groups in the benzothiazole backbone leads to significant alterations of bathochromic and hypsochromic shifts despite only slight differences in their molecular structures.

Magnetic Cu2+-chelated silica particles using polyacrylamide as a metal-chelating ligand was developed and used for the immobilization of laccase by coordination. The effect of pH and temperature on the enzymatic property of immobilized laccase and its catalytic capacity for pentachlorophenol (PCP) degradation were evaluated systemically. Compared with free laccase, the immobilized laccase showed improved acid adaptability and thermal stability. The immobilized laccase prepared in this work exhibited a good catalytic capacity for PCP removal from aqueous solutions.

The insulin-like growth factor-1 (IGF-1) plays an important role in the regulation of reproductive function. In the present study, we examined the effects of caloric restriction (CR) on the reproductive lifespan in rats and investigated the potential role of IGF-1. After 10 weeks of treatment, we determined the distribution of the ovarian follicles at various stages and measured the plasma level of IGF-1, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrogen (ESG). Our results show that IGF-1 level was decreased after CR and correlated with the decrease in the levels of LH, FSH and ESG. Moreover, a higher percentage of primordial follicles and surviving follicles was observed in CR rats than in control rats (P

The transport properties of C14 monocyclic ring sandwiched between two Al(1 0 0) electrodes are investigated by first-principle calculations. The variation of the equilibrium conductance as the function of the separation distance between the molecule and the electrodes is studied. C14 monocyclic ring shows metallic behavior according to the calculated equilibrium conductance. Electron transmission occurs through the lowest unoccupied molecular orbital (LUMO). With gate-voltage applied, it is found that the positive and negative gate-voltages can bring very different effect on the variation of equilibrium conductance. We also calculate the effects of adsorbing other atoms on the carbon ring such as oxygen and sulfur atoms. The results indicate that adsorption of this kind of electron-accepting impurity will decrease the conductance of the system.

We present first-principles studies on the transport properties of oligomers, polyphenyl dithiol, PP( n )DTs, sandwiched between two Al(1 0 0) electrodes. The variation of the current–voltage curve for PP(2)DT in different tilt angles is investigated systematically. The results indicate that PP(2)DT can be functioned as a molecular switch controlled by molecular conformation. We also study the variation of the equilibrium conductance and current–voltage properties of PP( n )DT as a function of n .

A chimeric plasminogen activator, GPRP-u-PA (144-411), consisting of the Gly-Pro-Arg-Pro tetrapeptide fused to the N-terminal of a truncated urokinase-type plasminogen activator (comprising Leu 144 through Leu 411), was produced by expression of the corresponding chimeric cDNA in Escherichia coli cells. After renaturation, the chimera was purified to homogeneity with specific amidolytic activity of 100,000 IU/mg protein. The chimera showed 6-fold greater affinity for fibrin clots than native low molecular weight urokinase (LUK) and 1.5-fold greater affinity than a chemical conjugate, GPRP-LUK, generating via coupling Gly-Pro-Arg-Pro tetrapeptide to native low molecular weight urokinase. The chimera had 2 to 3 fold greater fibrinolytic potency than native LUK in vitro. Fibrinogen had no influence on fibrinolysis of the chimera. The chimera consumed much less fibrinogen than native LUK.

Head-up tilt testing has gained acceptance as a tool for assessing susceptibility to neurally mediated syncopal syndromes (e.g., vasovagal syncope), and is currently being evaluated as a means of testing therapeutic interventions in these conditions. To assess reproducibility of head-up tilt testing and thereby assess the potential of such testing for immediate evaluation of a planned treatment, findings during 2 sequential 80 ° headup tilt tests were compared in 23 patients (age range 6.5 to 74 years) undergoing evaluation of syncope of unknown origin. Upright tilt was performed initially in the absence of drugs, and repeated if necessary during pharmacologic provocation by means of isoproterenol infusions of 1 and 3 μg/min (tilt 1). End points were syncope, maximal tolerated isoproterenol dose, or a tilt duration of 10 minutes. The second tilt test (tilt 2) was conducted after approximately 30 minutes of supine rest using the maximal provocative conditions used in tilt 1. Fifteen of 23 patients (65%) developed syncope in either tilt l or 2, while 8 of 23 (35%) remained asymptomatic. Tilt testing results were concordant (i.e., positive in both tests, or negative in both tests) in 20 of 23 (87%) patients. Concordance was, however, less among tilt-positive patients (12 of 15, 80%) since 3 patients were tilt-positive in tilt 1 only. In the 15 tiltpositive patients, heart rates, systolic and diastolic blood pressures at time of maximal tilt provocation were similar for both tilts (heart rate 1, 67 ± 27; 2, 82 ± 34 beats/min; systolk blood pressure 1: 50 ± 11 mm Hg; 2, 60 ± 21 mm Hg [p = not significant (NS)]; diastolic Wood pressure 1, 27 ± 12 mm Hg; 2, 33 ± 18 mm Hg [p = NS]). Furthermore, time from tilt onset to syncope did not differ in tilt 1 and 2. Among the 15 patients who were tilt-positive in tilt 1, the procedure was tolerated for 3.7 ± 2.1 minutes during the first test compared with 4.5 ± 3.2 minutes in the second test (p = NS). The outcomes were even closer if only patients developing syncope during both tests are considered (tilt 1, 3.7 ± 2.1 minutes vs tilt 2, 3.1 ± 1.8 minutes). Similarly, in the 8 tilt-test negative patients, minimal recorded systolic blood pressure and diastolic blood pressure did not differ in the 2 tests. Thus, upright tilt testing appears to exhibit a relatively high degree of reproducibility when a second study is performed on the same day. Consequently, 2 sequential tilt tests may be useful for assessing the immediate effect of therapeutic interventions on susceptibility to neurally mediated hypotension-bradycardia syndrome.