Statins for asymptomatic middle cerebral artery stenosis: The Regression of Cerebral Artery Stenosis study

BACKGROUND

The progression of cerebral atherosclerosis increases the risk of stroke and vascular events. Given the known benefits of statins in retarding coronary and carotid atherosclerosis progression, we studied the effects of statins on asymptomatic middle cerebral artery (MCA) stenosis progression.

METHODS

We conducted a randomized, double-blind, placebo-controlled study to evaluate the effects of simvastatin on the progression of MCA stenosis among stroke-free individuals who had mild to moderately elevated LDL cholesterol (3.0-5.0 mmol/l). Two hundred and twenty-seven subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The severity of MCA stenosis at baseline and at the end of the study was graded by MRA into normal, minimal (<10%), mild (10-49%), moderate (50-90%) and severe (>90%). The primary outcome was the change in grading of MCA stenosis over 2 years.

RESULTS

At the end of the study, the LDL cholesterol level decreased by 1.43 and 0.12 mmol/l for the active and placebo groups, respectively (p < 0.001). There was no significant difference in the proportion of patients having stable, progressive and regressive MCA stenosis between the placebo (72, 22 and 6%) and active groups (78.6, 15.5 and 5.8%). The all-cause mortality was significantly lower in the active group (n = 0) relative to the placebo group (n = 7, p = 0.014). Any clinical events were also lower in the active group (n = 5) than in the placebo group (n = 13, p = 0.052).

CONCLUSIONS

Simvastatin 20 mg daily had no apparent effect upon the evolution of asymptomatic MCA stenosis over 2 years.

Micro- and nanocubes of carbon with C8-like and blue luminescence

Micro- and nanocubes of carbon have been synthesized by laser ablation in liquid. The morphology and structure analyses indicated that these micro- and nanocubes are single crystals with a body-centered cubic structure with a lattice constant of 5.46 angstroms, which is so-called C 8-like structure, and they have a slightly truncated shape bounded mainly by (200) facets. A blue-purple luminescence at room temperature was observed in the cathodoluminescence spectrum of the synthesized single micro- and nanocube of carbon, which exhibited that this unique carbon nanomaterial is a new semiconductor with blue luminescence. The physical and chemical mechanisms of the synthesis of carbon micro- and nanocubes were pursued upon laser ablation in liquid.

Topotecan for ovarian cancer

BACKGROUND

Chemotherapeutic agents such as topotecan can be used to treat ovarian cancer. The effects of using topotecan as a therapeutic agent have not been previously been systematically reviewed.

OBJECTIVES

To systematically evaluate the effectiveness and safety of topotecan for the treatment of ovarian cancer.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), (Issue 4, 2006); Cochrane Gynaecological Cancer Review Group (CGCRG) Specialised Register (Cochrane Library Issue 4, 2006); MEDLINE (January 1990 to 27 July 2006); EMBASE (January 1990 to 27 July 2006); The European Organization for the Research and Treatment of Cancer (EORTC) database (to 1 August 2006); CBM (Chinese Biomedical Database) (January 1990 to 27 July 2006).

SELECTION CRITERIA

Randomised controlled trials (RCTs) which randomized patients with ovarian cancer to single or combined use of topotecan versus interventions without topotecan, or different remedies of topotecan.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted and analysed data.

MAIN RESULTS

Six studies including 1323 participants were eligible for this review (Gordon 2004a; Gore 2001a; Gore 2002; Hoskins 1998; Huinink 2004; Placido 2004) All studies, as reported, were identified as being of poor methodological quality. Topotecan had comparable effectiveness to prolong progression-free survival (PFS) compared with pegylated liposomal doxorubicin (PLD), (16.1 weeks versus 17.0 weeks; p = 0.095). Overall survival (OS) time was similar in participants using PLD compared with topotecan (56.7 weeks versus 60 weeks; p = 0.341). Topotecan was more hematologically toxic compared with paclitaxel or PLD, relative risks (RRs) of hematological events: ranged from 1.03 to 14.46 and 1.73 to 27.12 respectively. A 21-day cycle of topotecan was more toxic than a 42-day cycle (RRs of hematological and non-hematological events ranged from 1.03 to 8). Intravenous and oral topotecan had comparable toxicity. Topotecan delayed progression more effectively compared with paclitaxel (23.1 weeks versus 14 weeks, p = 0.0021). Participants were more likely to respond to topotecan on a 21-day cycle as opposed to a 42-day cycle (RR 7.23, 95% CI 0.94 to 55.36). Small tumor diameter, sensitivity to platinum-based chemotherapy was associated with better prognosis. Small sample size, methodological flaws and poor reporting of the included trials made measurement bias of the trials difficult to assess.

AUTHORS' CONCLUSIONS

Topotecan appears to have a similar level of effectiveness as paclitaxel and PLD, though with different patterns of side effects. Larger, well-designed RCTs are required in order to define an optimal regime.

Duodenal gastric metaplasia and Helicobacter pylori infection in patients with diffuse nodular duodenitis

Whether the regression of gastric metaplasia in the duodenum can be achieved after eradication of Helicobacter pylori is not clear. The aim of the present study was to investigate the relationship between H. pylori infection and gastric metaplasia in patients with endoscopic diffuse nodular duodenitis. Eighty-six patients with endoscopically confirmed nodular duodenitis and 40 control patients with normal duodenal appearance were investigated. The H. pylori-positive patients with duodenitis received anti-H. pylori triple therapy (20 mg omeprazole plus 250 mg clarithromycin and 400 mg metronidazole, all twice daily) for one week. A control endoscopy was performed 6 months after H. pylori treatment. The H. pylori-negative patients with duodenitis received 20 mg omeprazole once daily for 6 months and a control endoscopy was performed 2 weeks after treatment. The prevalence of H. pylori infection was 58.1%, and the prevalence of gastric metaplasia was 57.0%. Seventy-six patients underwent endoscopy again. No influence on the endoscopic appearance of nodular duodenitis was found after eradication of H. pylori or acid suppression therapy. However, gastric metaplasia significantly decreased and complete regression was achieved in 15/28 patients (53.6%) 6 months after eradication of H. pylori, accompanied by significant improvement of other histological alterations. Only mild chronic inflammation, but not gastric metaplasia, was found in the control group, none with H. pylori infection in the duodenal bulb. Therefore, H. pylori infection is related to the extent of gastric metaplasia in the duodenum, but not to the presence of diffuse nodular duodenitis.

Physical mechanism of blue-shift of UV luminescence of a single pencil-like ZnO nanowire

Cathodoluminescence spectroscopy is used to address the ultraviolet (UV) luminescence of a single pencil-like ZnO nanowire whose diameter gradually reduces from bottom to top in the range of 700-50 nm. It is found that the UV emission energy evidently shifts to the high energy with the ZnO nanowire's diameter decreasing and the blue-shift of 90 meV is observed when the nanowire diameter reduces to 50 from 700 nm. The physical mechanism of the UV blue-shift of the ZnO nanowire is attributed to the Burstein-Moss effect under the high carrier concentration.

Chinese medicinal herbs for influenza

BACKGROUND

Influenza is an acute respiratory communicable disease which, during epidemics, can cause high morbidity and mortality. Traditional Chinese medicinal herbs, often administered following a particular theory, may be a potential medicine of choice.

OBJECTIVES

To assess the effect of Chinese medicinal herbs in preventing and treating influenza, and to estimate the frequency of adverse effects.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2007), which includes the Cochrane Acute Respiratory Infections Review Group specialised register; MEDLINE (January 1966 to January 2007); EMBASE (January 1988 to January 2007); CBM (Chinese Biomedical Database) (January 1980 to January 2007); and the Chinese Cochrane Center's Controlled Trials Register (up to January 2007). We also searched Current Controlled Trials (www.controlled-trials.com) and the National Research Register (http://www.update-software.com/National/) for ongoing trials and reference lists of articles. For more information we telephoned and wrote to researchers in the field, as well as trial authors of studies evaluated in the review

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing traditional Chinese medicinal herbs with placebo, no treatment, or chemical drugs normally used in preventing and treating uncomplicated influenza patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality.

MAIN RESULTS

Two studies involving 1012 participants were reviewed. The methodological quality of both studies was 'poor'. Included RCTs separately compared two medicinal herbs with two different antiviral drugs, precluding any pooling of results. 'Ganmao' capsules were found to be more effective than amantadine in decreasing influenza symptoms and speeding recovery in one study, (in which adverse reactions were mentioned in the amantadine group although no data were reported). There were no significant differences between 'E Shu You' and ribavirin in treating influenza, nor in the occurrence of adverse reaction.

AUTHORS' CONCLUSIONS

The present evidence is too weak to support or reject the use of Chinese medicinal herbs for preventing and treating influenza. More RCTs with good methodological quality, larger numbers of participants and clear reporting are needed in the future. We recommend that all the clinical trials registered in the Chinese Clinical Trial Register and Chinese journals join in the Joint Statement of Establishing Chinese Clinical Trial Registration and Publishing System.

Experimental change on dopaminergic neurons in striatum of Parkinson disease rats

BACKGROUND

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by selective and progressive demise of dopamine-containing neurons in the midbrain. In this study, we observe the expression of c-Jun in the striatum of rats with 6-hydroxydopamine (6-OHDA)-lesions after apomorphine (APO) intraperitoneal injection (ip) in substantia nigra compacta (SNc), and to study the mechanism of the rotations behavior.

DESIGN

The 6-OHDA was unilaterally injected into rat right SNC. The APO- induced abnormal rotations were investigated on the 1st, 4th, 7th, 14th, 21st days after lesion, respectively. Meanwhile dopaminergic degeneration and c-Jun expression were observed with microscope. Nissl's body staining and immunohistochemical method (ABC) were employed to study the changes of tyrosine hydroxylase (TH) and c-Jun in DA neurons.

RESULTS

We found that the number of dopaminergic neurons decreased gradually in the lesioned site and those neurons' electron-microscopic structure was severe damaged. There were over 75% of dopaminergic neurons lost, contralateral rotations over 7 turns per minute and c-Jun expressing in the ipsilateral striatum.

CONCLUSION

Dopaminergic neurons deletion may be linked to upregulation of c-Jun.

A TiO2/AC composite photocatalyst with high activity and easy separation prepared by a hydrothermal method

In the present work, a TiO2/activated carbon (AC) photocatalyst with high activity and easy separation was prepared using a hydrothermal method. Phenol, methyl orange (MO) and Cr(VI) were used as target pollutants to test the activity and decantability. SEM, XRD, FTIR, diffuse reflectance spectra (UV/DRS) and N2 adsorption isotherms were used to characterize the crystalline and electronic structure. Results show that the AC composite has a significant effect on the TiO2 activity. With suitable AC content, the TiO2/xAC catalysts prepared were much more active. The TiO2/5AC catalyst exhibited easy separation and less deactivation after several runs, and was less sensitive to pH changes. UV/DRS revealed that no electronic bandgap changes in TiO2 occurred on addition of the AC. SEM and XRD results suggest that better TiO2 distribution can be achieved when an optimal AC content is used. A Ti-O-C bond was formed and a slight conjugation effect appeared between the AC bulk and TiO2. The advantages of the obtained TiO2/5AC catalyst revealed its great practical potential in wastewater treatment.

Activated carbon with excellent chromium(VI) adsorption performance prepared by acid-base surface modification

In the present work, activated carbon (AC) with excellent Cr(VI) adsorption performance especially at low concentrations was prepared by an acid-base surface modification method. Raw activated carbon (AC(0)) was first oxidized in boiling HNO(3) (AC(1)), then treated with a mixture of NaOH and NaCl (AC(2)). Batch equilibrium and continuous column adsorption were conducted to evaluate the adsorption performance. Boehm titration, elemental analysis, and N(2)/77K adsorption isotherm methods were used to characterize the surface properties and pore structure of modified ACs. The results revealed that the modified AC exhibited excellent Cr(VI) adsorption performance in terms of adsorption capacity and adsorption rate: AC(2)>AC(1)>AC(0). Modification caused S(BET) to decrease and the total number of surface oxygen acidic groups to increase. HNO(3) oxidization produced positive acid groups, and subsequently NaOH treatment replaced H(+) of surface acid groups by Na(+), and the acidity of AC decreased. The main cause of higher Cr(VI) adsorption capacity and rate for AC(2) was the presence of more oxygen surface acidic groups and suitable surface acidity. HNO(3)-NaOH modification shows potential for the preparation of high quality AC for the effective removal of low concentrations of Cr(VI).

[Effects of antiviral effects of agents and prognosis of chronic hepatitis B.]

BACKGROUND

To analyze the effects of difference antiviral agents and the effects of the treatments on long-term prognosis.

METHODS

Retrospective research method was applied.

RESULTS

About 40% of the patients were treated with interferon or lamivudine. After the treatment, in lamivudine group, the negative rate of HBV DNA was the highest. In the interferon group, the sero conversion rates of HBeAg/HBeAb were 22.9%. In the antiviral treatment patients, the disease progression and the occurrence of cirrhosis and liver cancer were much lower than those of the control groups. The mortality of cirrhosis and liver cancer in the HBeAg/HBeAb sero converted group was much lower than that of the group without HBeAg/HBeAb sero conversion groups (P less than 0.05).

CONCLUSION

The antiviral effects of interferon and lamivudine were better than those of the other drug groups. The antiviral drugs could relieve the disease progression and reduce the mortality of cirrhosis and liver cancer.

Development of a multifunctional and efficient conjugal plasmid for use in Streptomyces spp

A plasmid, pGB112, has recently been developed to transfer DNA from Escherichia coli to Streptomyces spp via conjugation. This technique made use of (A) E. coli replicon, (B) ampicillin (amp) resistance gene for selection in E. coli and thiostrepton (tsr) resistance gene for selection in Streptomyces, (C) a fragment of SCP2* replicon, (D) a 2.6 kb fragment of tra-cassette which consists of pIJ101 transfer gene (tra) and two ermE promoters, (E) a 0.8 kb fragment of oriT of (IncP) RK2. The results showed that this plasmid was able to transfer plasmid DNA from E. coli to Streptomyces coelicolor via conjugation, and that it could also transfer DNA between Streptomyces strains. Since this plasmid has both pBR322 and SCP2* replicons, it may provide a novel and useful method for genetic operation in E. coli and Streptomyces.

Structural identification of bitespiramycin metabolites in rat: a single oral dose study

Bitespiramycin is a macrolide antibiotic consisting of a mixture of some nine spiramycin ester derivatives. It has a similar spectrum of antibiotic activity to that of spiramycin but has superior pharmacokinetic properties. In this study, a rapid and facile LC/ESI-MSn method was applied to study the metabolism of bitespiramycin in rat following a single oral dose (80 mg kg-1). Concentrations of parent drug constituents and metabolites were determined in plasma, urine, feces and bile. Concentrations of parent drug constituents and metabolites in plasma were very low. In urine, feces and bile, parent drug constituents and 38 metabolites were identified on the basis of their chromatographic and mass spectrometric properties. The identity of 17 metabolites was confirmed by comparison with reference substances. The principal metabolites were the corresponding spiramycins formed by hydrolysis of the 4''-(3-methylbutanoate) groups. Other important metabolic pathways were: hydrolytic loss of the forosamine and mycarose sugars; aldehyde reduction; cysteine conjugation of the aldehyde group; and hydrolysis of the lactone ring. Products formed by lactone ring opening were found only in urine, and those formed by aldehyde reduction were found only in feces. Aldehyde reduction and hydrolytic loss of forosamine represent novel biotransformation pathways for spiramycin derivatives.

Comparison of subcooled liquid vapor pressures of polychlorinated dibenzo-p-dioxins and dibenzofurans predicted by QSPR and GC-RI methods

Subcooled liquid vapor pressures (P(L)) are of great importance for assessing the persistent behavior of organic pollutants. As P(L) cannot be determined by direct experiments, it is of interest to develop and evaluate various predictive methods. In the current study, gas chromatography retention index (GC-RI) and quantitative structure-property relationship (QSPR) methods were used to develop predictive models for P(L) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The model development was based on P(L) values converted from consistent experimental solid vapor pressures (P(S)). The P(L) values predicted by the two methods are highly consistent with each other, and in-between sets of values predicted by others. Since the QSPR method can be regarded as independent of experiments, and can be used to interpret intermolecular interactions that govern the magnitude of P(L), it may be superior to the GC-RI method.

Analysis of Energy Level Structure and Excited-State Dynamics in a Sm3+ Complex with Soft-Donor Ligands: Sm(Et2Dtc)3(bipy)

Using both laser-excited fluorescence and optical absorption methods, we have determined 57 crystal-field (CF) energy levels of Sm 3+ in crystals of Sm(Et2Dtc)3(bipy). The analysis of the energy levels is based on a model Hamiltonian consisting of both free-ion and CF terms. The CF modeling of the experimental energy levels yielded physically reasonable Hamiltonian parameters with a final rms deviation of 17.3 cm(-1). In comparison with Sm 3+ in other hosts, the CF splitting of Sm 3+ in the lattice of Sm(Et2Dtc)3(bipy) is rather weak. The observed fluorescence decay of the 4G(5/2) manifold is single-exponential, with a lifetime of 24.5 mus, indicating only one site of Sm3+ in the lattice. According to the Judd-Ofelt theory, values of three intensity parameters were obtained (Omega(2,4,6) = 1.57, 2.65, and 3.65, in units of 10(-20) cm(-1)). The calculated branching ratios for transitions from the 4G(5/2) manifold are in agreement with experimental values. The calculated radiative lifetime of the 4G(5/2) manifold is 3.24 ms, and the corresponding fluorescence quantum efficiency is only 0.75%. Efficient multiphonon relaxation processes induced by the localized high-frequency vibrational modes in the bipyridyl group may lead to the extremely low quantum efficiency observed. The thermal line broadening and shifts of the 4G(5/2)(1) --> 6F(1/2) transition were observed and fitted very well by the McCumber-Sturge equations with an assumption of Raman phonon scattering processes as the leading relaxation mechanism. The Debye temperature for this crystal is predicted to be 350 K.

Up-regulation of macrophage migration inhibitory factor in infants with acute neonatal necrotizing enterocolitis

AIMS

To investigate the role of macrophage migration inhibitory factor (MIF) and its downstream cytokine cascade in necrotizing enterocolitis (NEC).

METHODS AND RESULTS

The expression of MIF mRNA and protein in NEC guts was assayed by in situ hybridization and immunohistochemistry, respectively. Concentrations of MIF, interleukin (IL)-6 and IL-8 in the serum and in the supernatant of macrophage cultures were examined by ELISA. Increased expression of MIF mRNA and protein was observed in the NEC guts, mainly in the infiltrating macrophages in the mucosa and submucosal layers. Up-regulation of MIF was associated with the accumulation of macrophages and T cells. In addition, serum levels of MIF, IL-6 and IL-8 in NEC patients during the acute stage of the disease were significantly increased. The expression of MIF decreased both locally and systemically after the disease was resolved. MIF was also found to increase the secretion of IL-6 and IL-8 by macrophages isolated from healthy individuals in vitro in NEC.

CONCLUSIONS

MIF acts by stimulating macrophage production of IL-6 and IL-8. This further aggravates the inflammatory process by increasing the infiltration of neutrophils and activating inflammatory cells. The results of this study suggest that MIF plays an important role in the pathogenesis of NEC and may serve as a target for therapeutic intervention in NEC.