Plant-Derived Exosomal MicroRNAs Shape the Gut Microbiota

The gut microbiota can be altered by dietary interventions to prevent and treat various diseases. However, the mechanisms by which food products modulate commensals remain largely unknown. We demonstrate that plant-derived exosome-like nanoparticles (ELNs) are taken up by the gut microbiota and contain RNAs that alter microbiome composition and host physiology. Ginger ELNs (GELNs) are preferentially taken up by Lactobacillaceae in a GELN lipid-dependent manner and contain microRNAs that target various genes in Lactobacillus rhamnosus (LGG). Among these, GELN mdo-miR7267-3p-mediated targeting of the LGG monooxygenase ycnE yields increased indole-3-carboxaldehyde (I3A). GELN-RNAs or I3A, a ligand for aryl hydrocarbon receptor, are sufficient to induce production of IL-22, which is linked to barrier function improvement. These functions of GELN-RNAs can ameliorate mouse colitis via IL-22-dependent mechanisms. These findings reveal how plant products and their effects on the microbiome may be used to target specific host processes to alleviate disease.

Significant human beta-cell turnover is limited to the first three decades of life as determined by in vivo thymidine analog incorporation and radiocarbon dating

AIMS

Diabetes mellitus results from an absolute or relative deficiency of insulin-producing pancreatic β-cells. The turnover rate of adult human β-cells remains unknown. We employed two techniques to examine adult human islet β-cell turnover and longevity in vivo.

METHODS

Subjects enrolled in National Institutes of Health clinical trials received thymidine analogs [iododeoxyuridine (IdU) or bromodeoxyuridine (BrdU)] 8 d to 4 yr prior to death. Archival autopsy samples from 10 patients (aged 17-74 yr) were employed to assess β-cell turnover by scoring nuclear analog labeling within insulin-staining cells. Human adult β-cell longevity was determined by estimating the cells' genomic DNA integration of atmospheric (14)C. DNA was purified from pancreatic islets isolated from cadaveric donors; whole islet prep DNA was obtained from a 15-yr-old donor, and purified β-cell DNA was obtained from two donors (ages 48 and 80 yr). (14)C levels were then determined using accelerator mass spectrometry. Cellular "birth date" was determined by comparing the subject's DNA (14)C content relative to a well-established (14)C atmospheric prevalence curve.

RESULTS

In the two subjects less than 20 yr of age, 1-2% of the β-cell nuclei costained for BrdU/IdU. No β-cell nuclei costained in the eight patients more than 30 yr old. Consistent with the BrdU/IdU turnover data, β-cell DNA (14)C content indicated that the "birth date" of cells occurred within the subject's first 30 yr of life.

CONCLUSIONS

Under typical circumstances, human β-cells and their cellular precursors are established by young adulthood.

Cancer imaging phenomics toolkit: quantitative imaging analytics for precision diagnostics and predictive modeling of clinical outcome

The growth of multiparametric imaging protocols has paved the way for quantitative imaging phenotypes that predict treatment response and clinical outcome, reflect underlying cancer molecular characteristics and spatiotemporal heterogeneity, and can guide personalized treatment planning. This growth has underlined the need for efficient quantitative analytics to derive high-dimensional imaging signatures of diagnostic and predictive value in this emerging era of integrated precision diagnostics. This paper presents cancer imaging phenomics toolkit (CaPTk), a new and dynamically growing software platform for analysis of radiographic images of cancer, currently focusing on brain, breast, and lung cancer. CaPTk leverages the value of quantitative imaging analytics along with machine learning to derive phenotypic imaging signatures, based on two-level functionality. First, image analysis algorithms are used to extract comprehensive panels of diverse and complementary features, such as multiparametric intensity histogram distributions, texture, shape, kinetics, connectomics, and spatial patterns. At the second level, these quantitative imaging signatures are fed into multivariate machine learning models to produce diagnostic, prognostic, and predictive biomarkers. Results from clinical studies in three areas are shown: (i) computational neuro-oncology of brain gliomas for precision diagnostics, prediction of outcome, and treatment planning; (ii) prediction of treatment response for breast and lung cancer, and (iii) risk assessment for breast cancer.

CD36-dependent regulation of muscle FoxO1 and PDK4 in the PPAR delta/beta-mediated adaptation to metabolic stress

The transcription factor FoxO1 contributes to the metabolic adaptation to fasting by suppressing muscle oxidation of glucose, sparing it for glucose-dependent tissues. Previously, we reported that FoxO1 activation in C(2)C(12) muscle cells recruits the fatty acid translocase CD36 to the plasma membrane and increases fatty acid uptake and oxidation. This, together with FoxO1 induction of lipoprotein lipase, would promote the reliance on fatty acid utilization characteristic of the fasted muscle. Here, we show that CD36-mediated fatty acid uptake, in turn, up-regulates protein levels and activity of FoxO1 as well as its target PDK4, the negative regulator of glucose oxidation. Increased fatty acid flux or enforced CD36 expression in C(2)C(12) cells is sufficient to induce FoxO1 and PDK4, whereas CD36 knockdown has opposite effects. In vivo, CD36 loss blunts fasting induction of FoxO1 and PDK4 and the associated suppression of glucose oxidation. Importantly, CD36-dependent regulation of FoxO1 is mediated by the nuclear receptor PPARdelta/beta. Loss of PPARdelta/beta phenocopies CD36 deficiency in blunting fasting induction of muscle FoxO1 and PDK4 in vivo. Expression of PPARdelta/beta in C(2)C(12) cells, like that of CD36, robustly induces FoxO1 and suppresses glucose oxidation, whereas co-expression of a dominant negative PPARdelta/beta compromises FoxO1 induction. Finally, several PPRE sites were identified in the FoxO1 promoter, which was responsive to PPARdelta/beta. Agonists of PPARdelta/beta were sufficient to confer responsiveness and transactivate the heterologous FoxO1 promoter but not in the presence of dominant negative PPARdelta/beta. Taken together, our findings suggest that CD36-dependent FA activation of PPARdelta/beta results in the transcriptional regulation of FoxO1 as well as PDK4, recently shown to be a direct PPARdelta/beta target. FoxO1 in turn can regulate CD36, lipoprotein lipase, and PDK4, reinforcing the action of PPARdelta/beta to increase muscle reliance on FA. The findings could have implications in the chronic abnormalities of fatty acid metabolism associated with obesity and diabetes.

Gastrodin and p-hydroxybenzyl alcohol facilitate memory consolidation and retrieval, but not acquisition, on the passive avoidance task in rats

Gastrodin (GAS) and p-hydroxybenzyl alcohol (HBA) which is an aglycone of gastrodin, are active ingredients of Gastrodia elata Blume. In this study, we attempted to investigate the effects of acute administration of GAS and HBA on learning and memory processes such as acquisition, consolidation and retrieval, on the passive avoidance task in rats; piracetam was used as a positive control. Scopolamine, impairing learning acquisition, shortened the step-through latency in the retention test in rats. GAS and HBA did not prolong the step-through latency induced by scopolamine in the passive avoidance task, but piracetam could prolong the step-through latency induced by scopolamine. Cycloheximide, impairing memory consolidation, shortened the step-through latency in the retention test in rats. GAS at 50 mg/kg, HBA at 5 mg/kg and piracetam at 100 mg/kg could prolong the step-through latency induced by cycloheximide in the passive avoidance task. Apomorphine, impairing memory retrieval, shortened the step-through latency in the retention test in rats. GAS at 5 mg/kg, HBA at 1 mg/kg and piracetam at 300 mg/kg could prolong the step-through latency induced by apomorphine in the passive avoidance task. From the above results, we concluded that the facilitating effects of HBA on learning and memory are better than those of GAS. In conclusion, GAS and HBA can improve cycloheximide- and apomorphine-induced amnesia, but not scopolamine-induced acquisition impairment in rats. Thus, GAS and HBA can facilitate memory consolidation and retrieval, but not acquisition. The facilitating effects of GAS and HBA are different from those of piracetam.

Human oocyte maturation is dependent on LH-stimulated accumulation of the epidermal growth factor-like growth factor, amphiregulin

BACKGROUND

The LH surge promotes ovulation via activation of multiple signaling networks in the ovarian follicle. Studies in animal models have shown the importance of LH-induced activation of the epidermal growth factor (EGF)signaling network in critical peri-ovulatory events. We investigated the biological significance of regulatory mechanisms mediated by EGF-like growth factors during LH stimulation in humans.

METHODS

We characterized the EGF signaling network in mature human ovarian follicles using in vivo and in vitro approaches. Amphiregulin (AREG) levels were measured in 119 follicular fluid (FF) samples from IVF/ICSI patients. Biological activity of human FF was assessed using in vitro oocyte maturation, cumulus expansion and cell mitogenic assays.

RESULTS

AREG is the most abundant EGF-like growth factor accumulating in the FF of mature follicles of hCG-stimulated patients. No AREG was detected before the LH surge or before hCG stimulation of granulosa cells in vitro, demonstrating that the accumulation of AREG requires gonadotrophin stimulation. Epiregulin and betacellulin mRNA were detected in both human mural and cumulus granulosa cells, although at significantly lower levels than AREG. FF from stimulated follicles causes cumulus expansion and oocyte maturation in a reconstitution assay. Immunodepletion of AREG abolishes the ability of FF to stimulate expansion (P < 0.0001) and oocyte maturation (P < 0.05), confirming the biological activity of AREG. Conversely, mitogenic activity of FF remained after depletion of AREG, indicating that other mitogens accumulate in FF. FF from follicles yielding an immature germinal vesicle oocyte or from an oocyte that develops into an aberrant embryo contains lower AREG levels than that from follicles yielding a healthy oocyte (P = 0.008).

CONCLUSIONS

EGF-like growth factors play a role in critical peri-ovulatory events in humans, and AREG accumulation is a useful marker of gonadotrophin stimulation and oocyte competence.

Anxiolytic effect of seed of Ziziphus jujuba in mouse models of anxiety

The aim of the present study was to investigate the ethanolic extract of Semen Ziziphi jujuba (SZJE) induced anxiolytic effect. The SZJE was orally administered to male ICR mice, at 0.5, 1.0 and 2. 0 g/kg, 30 min before the behavioral evaluation in the black and white test (BWT) and elevated plus maze (EPM). The SZJE at the dosage 0.5-2.0 g/kg increased the first time entry, total changes and times spent in the white chamber of the BWT. The SZJE at the dosage 0.5-1.0 g/kg increased the percentage of time-spent and the percentage of arm entries in the open arms of the EPM and decreased the percentage of time-spent and the percentage of arm entries in the closed arms of the EPM. Furthermore, the SZJE at the dosage of 1. 0 g/kg prolonged the hexobarbital-induced sleeping time in mice and decreased the locomotor activity in rats. These results suggested that SZJE possessed anxiolytic effect at lower dose and sedative effect at higher dose.

Thermodynamic and kinetic characterization of the binding of the TATA binding protein to the adenovirus E4 promoter

A thermodynamic analysis of the binding of the TATA binding protein (TBP) from Saccharomyces cerevisiae to the adenovirus E4 promoter was conducted using quantitative DNase I "footprint" titration techniques. These studies were conducted to provide a foundation for studies of TBP structure-function relations and its assembly into transcription preinitiation complexes. The binding of TBP to the E4 promoter is well described by the Langmuir binding polynomial, suggesting that no linked equilibria contribute to the binding reaction under the conditions examined. Van't Hoff analysis yielded a nonlinear dependence on temperature with the TBP-E4 promoter interaction displaying maximal affinity at 30 degrees C. An unusually negative value of the apparent standard heat capacity change, delta Cp degrees = -3.5 +/- 0.5 kcal/mol.K, was determined from these data. The dependence of the TBP-E4 promoter interaction on [KCl] indicates that 3.6 +/- 0.3 K+ ions are displaced upon complex formation. Within experimental error, no linkage of proton binding with the TBP-E4 promoter interaction is detectable between pH 5.9 and 8.7. Rates of association of TBP for the E4 promoter were obtained using a novel implementation of a quench-flow device and DNase I "footprinting" techniques. The value determined for the second-order rate constant at pH 7.4, 100 mM KCl, 5 mM MgCl2, 1 mM CaCl2, 30 degrees C (ka = 5.2 +/- 0.5) x 10(5) M-1 s-1) confirms the results obtained by Hawley and co-workers [Hoopes, B.C., LeBlanc, J.F., & Hawley, D.K. (1992) J. Biol. Chem. 267, 11539-11547] and extends them through TBP concentrations of 636 nM.(ABSTRACT TRUNCATED AT 250 WORDS)

Converting Escherichia coli RNA polymerase into an enhancer-responsive enzyme: role of an NH2-terminal leucine patch in sigma 54

The protein sigma 54 associates with Escherichia coli core RNA polymerase to form a holoenzyme that binds promoters but is inactive in the absence of enhancer activation. Here, mutants of sigma 54 enabled polymerases to transcribe without enhancer protein and adenosine triphosphate. The mutations are in leucines within the NH2-terminal glutamine-rich domain of sigma 54. Multiple leucine substitutions mimicked the effect of enhancer protein, which suggests that the enhancer protein functions to disrupt a leucine patch. The results indicate that sigma 54 acts both as an inhibitor of polymerase activity and as a receptor that interacts with enhancer protein to overcome this inhibition, and that these two activities jointly confer enhancer responsiveness.

High-level allogeneic chimerism achieved by prenatal tolerance induction and postnatal nonmyeloablative bone marrow transplantation

Clinical application of allogeneic bone marrow transplantation (BMT) has been limited by toxicity related to cytoreductive conditioning and immune response. In utero hematopoietic stem cell transplantation (IUHSCT) is a nonablative approach that achieves mixed chimerism and donor-specific tolerance but has been limited by minimal engraftment. We hypothesized that mixed chimerism achieved by IUHSCT could be enhanced after birth by nonmyeloablative total body irradiation (TBI) followed by same-donor BMT. To test this hypothesis, mixed chimerism was created by IUHSCT in a major histocompatibility complex-mismatched strain combination. After birth, chimeric animals received nonmyeloablative TBI followed by transplantation of donor congenic bone marrow cells. Our results show that: (1) low-level chimerism after IUHSCT can be enhanced to high-level chimerism by this strategy; (2) enhancement of chimerism is dependent on dose of TBI; (3) the mechanism of TBI enhancement is via a transient competitive advantage for nonirradiated hematopoietic stem cells; (4) engraftment observed in the tolerant, fully allogeneic IUHSC transplant recipient is equivalent to a congenic recipient; and (5) host-reactive donor lymphocytes are deleted with no evidence of graft-versus-host disease. This study supports the concept of prenatal tolerance induction to facilitate nonmyeloablative postnatal strategies for cellular therapy. If clinically applicable, such an approach could dramatically expand the application of IUHSCT.

The ameliorating effects of the cognitive-enhancing Chinese herbs on scopolamine-induced amnesia in rats

Ameliorating effects were investigated of the cognitive-enhancing Chinese herbs administered orally for 1 week-Panax ginseng (PG), Panax notoginseng (PNG), Dioscorea opposita (DO), Gastrodia elata (GE), Salvia miltiorrhiza (SM), Acorus gramineus (AG), Coptis chinensis (CC), Polygonum multiflorum (PM), Cyperus rotundus (CR) and Psoralea corylifolia (PC)-on the scopolamine (SCOP)-induced amnesia by using a passive avoidance task in rats. Of ten Chinese herbs, only PG, PNG, GE and CC prolonged the SCOP-shortened STL. These results revealed that PG, PNG GE and CC administered orally for 1 week improved the SCOP-induced learning and memory deficit in rats.

Pharmacokinetics of rifabutin

We investigated the pharmacokinetics of rifabutin in 15 male patients as part of a phase I trial of the treatment of early symptomatic human immunodeficiency virus infection. Six or more patients were studied at each of four different oral dosage levels: 300, 600, 900, and 1,200 mg/day. Twelve studies were also conducted with tracer doses of intravenous radiolabeled [14C]rifabutin. Blood and urine samples were collected for at least 72 h after the first (day 1) and last (day 28) doses of rifabutin and analyzed by high-pressure liquid chromatography. The plasma concentration data were best described by a two-compartment open model with a terminal half-life of 36 h. Rifabutin was rapidly absorbed, reaching a peak concentration about 2 to 3 h after an oral dose. Peak and trough concentrations for the 1,200-mg dose were 907 and 194 ng/ml, respectively. Total body clearance was 10 to 18 liters/h. Oral bioavailability was 12 to 20%. The drug was moderately bound to plasma proteins with a free fraction of 29 +/- 2% (mean +/- standard deviation). About 10% of an administered intravenous dose of rifabutin is excreted into the urine unchanged. Renal clearance was 1.5 +/- 0.2 liters/h. The volume of distribution was large (8 to 9 liters/kg), suggesting extensive distribution into the tissues. The area under the curve for the last dose was smaller than that of the first dose, suggesting possible induction of drug-metabolizing enzymes.

Anti-hepatitis B virus effects of wogonin isolated from Scutellaria baicalensis

By using an HBV-producing cell line (MS-G2) in vitro culture system, we found that wogonin isolated from Scutellaria baicalensis can suppress HBV surface antigen production (P < 0.001) without evidence of cytotoxicity. By assaying the endogenous HBV DNA polymerase activity, we found that both the relaxed circular and the linear forms of HBV DNA are significantly reduced in the wogonin-treated group. Wogonin deserves to be further evaluated for the treatment of human HBV infection.

Repeat pediatric visits to a general emergency department

STUDY OBJECTIVE

To determine the rate of repeat visits among children cared for in a general emergency department and associated demographic and clinical variables.

METHODS

We carried out a chart review of patients seen in the ED of a general hospital serving both inner-city and suburban populations. Our subjects were all children younger than 18 years seen in the study ED between July 1, 1992, and June 30, 1993 (N = 4,276).

RESULTS

We found 291 repeat visits (defined as a subsequent visit within 14 days) n 245 children. Among the 242 repeat visits for related complaints, 200 were unanticipated and most without a clear medical need. Mantel-Haenszel adjusted odds ratios (MHORs) showed a significantly increased risk of repeat visit with public insurance (controlled for age: MHOR, 2.57, and 95% confidence interval [CI], 1.93 to 3.43; controlled for race: MHOR, 2.70, and 95% CI, 1.99 to 3.66) and age younger than 2 years (controlled for insurance MHOR, 1.67, and 95% CI, 1.27 to 2.19; controlled for race: MHOR, 1.89, and 95% CI, 1.47 to 2.47.

CONCLUSION

Repeat visits were more likely for respiratory diagnoses and less likely for minor trauma. Both visits and repeat visits were more likely in patients from poorer census tracts than in those from equidistant, more affluent ones.

Evaluation of commercially available small RNASeq library preparation kits using low input RNA

Background

Evolving interest in comprehensively profiling the full range of small RNAs present in small tissue biopsies and in circulating biofluids, and how the profile differs with disease, has launched small RNA sequencing (RNASeq) into more frequent use. However, known biases associated with small RNASeq, compounded by low RNA inputs, have been both a significant concern and a hurdle to widespread adoption. As RNASeq is becoming a viable choice for the discovery of small RNAs in low input samples and more labs are employing it, there should be benchmark datasets to test and evaluate the performance of new sequencing protocols and operators. In a recent publication from the National Institute of Standards and Technology, Pine et al., 2018, the investigators used a commercially available set of three tissues and tested performance across labs and platforms.

Results

In this paper, we further tested the performance of low RNA input in three commonly used and commercially available RNASeq library preparation kits; NEB Next, NEXTFlex, and TruSeq small RNA library preparation. We evaluated the performance of the kits at two different sites, using three different tissues (brain, liver, and placenta) with high (1 μg) and low RNA (10 ng) input from tissue samples, or 5.0, 3.0, 2.0, 1.0, 0.5, and 0.2 ml starting volumes of plasma. As there has been a lack of robust validation platforms for differentially expressed miRNAs, we also compared low input RNASeq data with their expression profiles on three different platforms (Abcam Fireplex, HTG EdgeSeq, and Qiagen miRNome).

Conclusions

The concordance of RNASeq results on these three platforms was dependent on the RNA expression level; the higher the expression, the better the reproducibility. The results provide an extensive analysis of small RNASeq kit performance using low RNA input, and replication of these data on three downstream technologies.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4726-6) contains supplementary material, which is available to authorized users.

Antihypertensive effects of DL-tetrahydropalmatine: an active principle isolated from Corydalis

1. The effects of DL-tetrahydropalmatine (DL-THP) on cardio-vascular function and hypothalamic release of monoamines were assessed in rats under urethane anaesthesia. 2. Intravenous administration of DL-THP (1-10 mg/kg) produced hypotension, bradycardia, a decrease in hypothalamic serotonin and noradrenaline release and an increase in hypothalamic dopamine release in rats. 3. Intrahypothalamic administration of DOI (a serotonergic 5-HT2 receptor antagonist) or apomorphine (a dopamine D2-receptor agonist) produced the opposite effects and reversed DL-THP-induced hypotension and bradycardia. 4. The data suggest that DL-THP acts through the 5-HT2 and/or D2-receptor antagonism in the hypothalamus to induce hypotension and bradycardia in rats.

Optimal control landscapes for quantum observables

The optimal control of quantum systems provides the means to achieve the best outcome from redirecting dynamical behavior. Quantum systems for optimal control are characterized by an evolving density matrix and a Hermitian operator associated with the observable of interest. The optimal control landscape is the observable as a functional of the control field. The features of interest over this control landscape consist of the extremum values and their topological character. For controllable finite dimensional quantum systems with no constraints placed on the controls, it is shown that there is only a finite number of distinct values for the extrema, dependent on the spectral degeneracy of the initial and target density matrices. The consequences of these findings for the practical discovery of effective quantum controls in the laboratory is discussed.

DNA sequence-specific recognition by the Saccharomyces cerevisiae "TATA" binding protein: promoter-dependent differences in the thermodynamics and kinetics of binding

The equilibrium binding and association kinetics of the Saccharomyces cerevisiae TATA Binding Protein (TBP) to the E4 and Major Late promoters of adenovirus (TATATATA and TATAAAAG, respectively), have been directly compared by quantitative DNase I titration and quench-flow "footprinting". The equilibrium binding of TBP to both promoters is described by the equilibrium TBP + DNA"TATA" left and right arrow TBP-DNA"TATA". The salt dependence of TBP binding to both promoters is identical within experimental error while the temperature dependence differs significantly. The observed rate of association follows simple second-order kinetics over the TBP concentration ranges investigated. The salt and temperature dependencies of the second-order association rate constants for TBP binding the two promoters reflect the dependencies determined by equilibrium binding. The TBP-E4 promoter interaction is entropically driven at low temperature and enthalpically driven at high temperature while the TBP-Major Late promoter reaction is entropically driven over virtually the entire temperature range investigated. These data suggest that the reaction mechanisms of TBP-promoter interactions are TATA sequence-specific and provide for differential regulation of promoters as a function of environmental variables.

Comparison of the DNA association kinetics of the Lac repressor tetramer, its dimeric mutant LacIadi, and the native dimeric Gal repressor

The rates of association of the tetrameric Lac repressor (LacI), dimeric LacIadi (a deletion mutant of LacI), and the native dimeric Gal repressor (GalR) to DNA restriction fragments containing a single specific site were investigated using a quench-flow DNase I "footprinting" technique. The dimeric proteins, LacIadi and GalR, and tetrameric LacI possess one and two DNA binding sites, respectively. The nanomolar protein concentrations used in these studies ensured that the state of oligomerization of each protein was predominantly either dimeric or tetrameric, respectively. The bimolecular association rate constants (ka) determined for the LacI tetramer exceed those of the dimeric proteins. The values of ka obtained for LacI, LacIadi, and GalR display different dependences on [KCl]. For LacIadi and GalR, they diminish as [KCl] increases from 25 mM to 200 mM, approaching rates predicted for three-dimensional diffusion. In contrast, the ka values determined for the tetrameric LacI remain constant up to 300 mM [KCl], the highest salt concentration that could be investigated by quench-flow footprinting. The enhanced rate of association of the tetramer relative to the dimeric proteins can be modeled by enhanced "sliding" (Berg, O. G., Winter, R. B., and von Hippel, P. H. (1981) Biochemistry 20, 6929-6948) of the LacI tetramer relative to the LacIadi dimer or a combination of enhanced sliding and the superimposition of "direct transfer" mediated by the bidentate DNA interactions of the tetramer.

Effects of Gastrodia elata and its active constituents on scopolamine-induced amnesia in rats

The effects of the rhizome of Gastrodia elata Blume (Orchidaceae) (abbreviated as GE) and its active constituents on learning and memory by using the one-trial passive avoidance task were studied in rats. At the 1.0 g/kg dose administered for one week, the methanol extract of GE significantly prolonged the shortened step-through latency induced by scopolamine in the passive avoidance task. Furthermore, at the 50.0 mg/kg dose administered for one week, the ethyl acetate and n-butanol fractions of the methanol extract prolonged the shortened step-through latency induced by scopolamine in rats. Gastrodin, isolated from the n-butanol fraction of the methanol extract, and p-hydroxybenzyl alcohol, isolated from the ethyl acetate fraction of the methanol extract, also significantly prolonged the shortened step-through latency induced by scopolamine on the passive avoidance task. These results suggested that gastrodin and p-hydroxybenzyl alcohol may be the active constituents of GE.

Quantum optimal control: Hessian analysis of the control landscape

Seeking an effective quantum control entails searching over a landscape defined as the objective as a functional of the control field. This paper considers the problem of driving a state-to-state transition in a finite level quantum system, and analyzes the local topology of the landscape of the final transition probability in terms of the variables specifying the control field. Numerical calculation of the eigenvalues of the Hessian of the transition probability with respect to the control field variables reveals systematic structure in the spectra reflecting the existence of a generic and simple control landscape topology. An illustration shows that the number of nonzero Hessian eigenvalues is determined by the number of quantum states in the system. The Hessian eigenvectors associated with its nonzero eigenvalues are shown to give insight into the cooperative roles of the control variables. The practical consequences of these findings for quantum control are discussed.

Effects of palmatine on isometric force and intracellular calcium levels of arterial smooth muscle

The effects of palmatine on isometric force and intracellular free calcium levels ([Ca2+]i) were determined in isolated rat arterial strips. Palmatine dose-dependently relaxed the contractile responses stimulated by phenylephrine (PE) in aortic strips. In contrast, it only partially relaxed aortic strips contracted by 51 mM KCl. Pretreatment with palmatine shifted the dose-response curves of PE both rightwards and downwards in a dose-dependent manner. When Ca2+-free solution and re-addition of Ca2+ were applied to assess PE-induced phasic and tonic contractions, palmatine was found to be effective in inhibiting both contractions. The effects of palmatine on intracellular calcium levels were measured with the bioluminescent calcium indicator aequorin in rat tail artery strips. Palmatine caused a concomitant, dose-dependent decrease in PE-activated isometric force and [Ca2+]i, resulting in small changes in the [Ca2+]i-force relationship. These results suggest that vasodilatory effect of palmatine was mediated by reducing [Ca2+]i as well as affecting [Ca2+]i sensitivity of the contractile apparatus. Palmatine-induced [Ca2+]i decreases appeared to involve decreases in both Ca2+ release from intracellular stores and Ca2+ influx through calcium channels.

Analysis of trinucleotide repeats in different SCA loci in spinocerebellar ataxia patients and in normal population of Taiwan

OBJECTIVE

To identify various subtypes of spinocerebellar ataxias (SCAs) among autosomal dominant cerebellar ataxia (ADCA) patients referred to our research center, SCA1, SCA2, SCA3/MJD (Machado-Joseph disease), SCA6, SCA7, SCA8 and SCA12 loci were assessed for expansion of trinucleotide repeats.

PATIENTS AND METHODS

A total of 211 ADCA patients, including 202 patients with dominantly inherited ataxia from 81 Taiwanese families and nine patients with sporadic ataxia, were included in this study and subjected to polymerase chain reaction (PCR) analysis. The amplified products of all loci were analyzed on both 3% agarose gels and 6% denaturing urea-polyacrylamide gels. PCR-based Southern blots were also applied for the detection of SCA7 locus.

RESULTS

The SCA1 mutation was detected in six affected individuals from one family (1.2%) with expanded alleles of 50-53 CAG repeats. Fourteen individuals from nine families (11%) had a CAG trinucleotide repeat expansion at the SCA2 locus, while affected SCA2 alleles have 34-49 CAG repeats. The SCA3/MJD CAG trinucleotide repeat expansion in 60 affected individuals from 26 families (32%) was expanded to 71-85 CAG repeats. As for the SCA7 locus, there were two affected individuals from one family (1.2%) possessed 41 and 100 CAG repeats, respectively. However, we did not detect expansion in the SCA6, SCA8 and SCA12 loci in any patient.

CONCLUSIONS

The SCA3/MJD CAG expansion was the most frequent mutation among the SCA patients. The relative prevalence of SCA3/MJD in Taiwan was higher than that of SCA2, SCA1 and SCA7.

Effect of long-term administration of berberine on scopolamine-induced amnesia in rats

The effect of berberine (BER) on scopolamine (SCOP)-induced amnesia was investigated in a step-through passive avoidance task in rats. It was observed that BER at the doses of 0.1 and 0.5 g/kg after 7-day or 14-day administration significantly improved SCOP-induced amnesia. The anti-amnesic effect of BER after 14-day administration on the SCOP-induced amnesia was significantly augmented by physostigmine or neostigmine, and completely reversed by scopolamine N-methylbromide. These results suggest that the antiamnesic effect of BER after 14-day administration may be related to the increase in the peripheral and central cholinergic neuronal system activity.