Association between CYP2D6 *10 genotype and survival of breast cancer patients receiving tamoxifen treatment

BACKGROUND

Human cytochrome P450 2D6 (CYP2D6) genotype may affect the efficacy of tamoxifen treatment in Caucasian women with breast cancer. The most common polymorphism of CYP2D6 in Chinese women is variant 10 (188 C to T).

PATIENTS AND METHODS

Tamoxifen and 4-hydroxytamoxifen (4OHtam) were measured in the serum of 37 women with breast cancer who were receiving tamoxifen treatment. The association between CYP2D6 *10 genotype and survival was determined in a cohort of 293 women with breast cancer who received tamoxifen (n = 152) or who did not (n = 141).

RESULTS

The serum 4OHtam concentrations were significantly lower in women with the CYP2D6 *10 homozygous variant T/T genotype than in those with the homozygous wild-type C/C genotype (P = 0.04). Among tamoxifen-treated women, women with the T/T genotype had a significantly worse disease-free survival (DFS) than those with the C/C or C/T genotype, and the T/T genotype remained an independent prognostic factor of DFS in multivariate analysis (hazard ratio = 4.7; 95% confidence interval = 1.1-20.0; P = 0.04). Among women who did not receive tamoxifen, there was no significant association between CYP2D6 *10 genotype and survival.

CONCLUSION

In tamoxifen-treated patients, women with the CYP2D6 *10 T/T genotype have a lower 4OHtam level in the serum and a worse clinical outcome.

The interfacial structure and Young's modulus of peptide films having switchable mechanical properties

We report the structure and Young's modulus of switchable films formed by peptide self-assembly at the air-water interface. Peptide surfactant AM1 forms an interfacial film that can be switched, reversibly, from a high- to low-elasticity state, with rapid loss of emulsion and foam stability. Using neutron reflectometry, we find that the AM1 film comprises a thin (approx. 15A) layer of ordered peptide in both states, confirming that it is possible to drastically alter the mechanical properties of an interfacial ensemble without significantly altering its concentration or macromolecular organization. We also report the first experimentally determined Young's modulus of a peptide film self-assembled at the air-water interface (E=80MPa for AM1, switching to E<20MPa). These findings suggest a fundamental link between E and the macroscopic stability of peptide-containing foam. Finally, we report studies of a designed peptide surfactant, Lac21E, which we find forms a stronger switchable film than AM1 (E=335MPa switching to E<4MPa). In contrast to AM1, Lac21E switching is caused by peptide dissociation from the interface (i.e. by self-disassembly). This research confirms that small changes in molecular design can lead to similar macroscopic behaviour via surprisingly different mechanisms.

The role of pro-inflammatory factors in mediating the effects on the fetus of prenatal undernutrition: implications for schizophrenia

Exposure to prenatal undernutrition or malnutrition increases the risk of schizophrenia, although little is known about the mechanism. Pro-inflammatory factors are critical in brain development, and are believed to play an important role in neurodevelopmental disorders associated with prenatal exposure to infection, including schizophrenia. However it is not known whether pro-inflammatory factors also mediate the effects on the fetus of prenatal malnutrition or undernutrition. In this study, we established a new prenatal undernourished rat model induced by maternal exposure to a diet restricted to 50% of the low (6%) protein diet (RLP50). We observed the disappearance of maternal nest-building behavior in the RLP50 dams, increased levels of TNFA and IL6 in the placentas (P<0.001; P=0.879, respectively) and fetal livers (P<0.001; P<0.05, respectively), and a decrease in the fetal brains (P<0.05; P<0.01, respectively). Our results are similar to previous studies of maternal infection, which implies that a common pathway mediated by pro-inflammatory factors may contribute to the brain development, consequently increasing the risk of schizophrenia and other psychiatric diseases programmed by varied maternal adversities. We also provide a new prenatal undernourished model for researching prenatal problems, which differs from previous malnourished model in terms of the maternal behavior of dams and of observed pro-inflammatory factor levels in fetal tissues.

Corticosteroids for preventing postherpetic neuralgia

BACKGROUND

Postherpetic neuralgia is a common serious complication of herpes zoster. Corticosteroids are anti-inflammatory and might be beneficial.

OBJECTIVES

To examine the efficacy of corticosteroids in preventing postherpetic neuralgia.

SEARCH STRATEGY

Search for randomised or quasi-randomised controlled trials for corticosteroids for preventing postherpetic neuralgia in MEDLINE (1950 to 2006), EMBASE (1980 to 2006), LILACS (1982 to 2005), the Chinese Biomedical Retrieval System (1978 to 2006) and the Cochrane Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 3, 2006). Date of most recent search: September 2006.

SELECTION CRITERIA

Types of studies: quasi-randomised or randomised controlled trials.

TYPES OF PARTICIPANTS

people of all ages with herpes zoster of all degrees of severity within seven days after onset. Types of interventions: all kinds of corticosteroids given by oral, intramuscular or intravenous routes during the acute stage (starting within one week of onset of the rash) compared with no treatment or placebo, but not with other treatments. We also included trials which compared corticosteroids plus routine treatment with placebo plus routine treatment. Types of outcome measures: Primary: the presence of postherpetic neuralgia six months after the onset of the acute herpetic rash. Secondary: pain severity measured by a validated visual analogue scale or numerical descriptive scale after three, six and 12 months; quality of life measured with the short form 36 questionnaire after six months; adverse events during or within two weeks after stopping treatment.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent reviewers.

MAIN RESULTS

Five trials were included with altogether 787 participants. All were randomised, double-blind, placebo-controlled parallel group studies. Our primary outcome measure was the presence of postherpetic neuralgia six months after the onset of the acute herpetic rash. There was no significant difference between the corticosteroid and control groups for the primary outcome (RR 1.27, 95% CI 0.20 to 7.97). There was also no significant difference between the corticosteroid plus antiviral agents and placebo plus antiviral agents groups for the primary outcome (RR 0.90, 95% CI 0.40 to 2.03). No included trials evaluated pain severity with a validated visual analogue scale or numerical descriptive scale and also no trials measured quality of life with the Short Form 36 questionnaire. Adverse events during or within two weeks after stopping treatment were reported by all five included trials, but after meta-analysis, there was no significant difference in any serious adverse event (death, acute cardiac insufficiency, rash dissemination, bacterial pneumonia or haematemesis) or non serious adverse event (dizziness, nausea, vomiting, hypertension or hyperglycaemia).

AUTHORS' CONCLUSIONS

There was insufficient evidence to conclude that corticosteroids are safe or effective in the prevention of postherpetic neuralgia. More randomised controlled trials with a greater number of participants are needed to determine reliably whether there is real benefit (or harm) from the use of corticosteroid therapy to prevent postherpetic neuralgia. Future trials should measure function and quality of life.

[Reversal of multidrug resistance of gastric cancer cells by down-regulation of CIAPIN1 with CIAPIN1 siRNA]

The overexpression of a new cytokine-induced apoptosis inhibitor 1 (CIAPIN1) gene has been shown previously to promote a multidrug resistant phenotype in gastric cancer cells through the upregulation of MDR1 and MRP1. In the present study, we constructed the siRNA eukaryotic expression vectors of CIAPIN1 and transfected them into SGC7901/VCR cells to examine whether the down regulation of CIAPIN1 increased cell sensitivity towards chemotherapeutic drugs. After transfection, the expression of CIAPIN1 was dramatically decreased in CIAPIN1 siRNA transfectants compared with that in parental cells and empty vector control cells. The down-regulation of CIAPIN1 significantly enhanced the sensitivity of SGC7901/VCR cells to vincristine (VCR), adriamycin (ADR) and etoposide (VP-16), but not to 5-fluorouracil (5-FU) and cisplatin (CDDP). Cell capacity to efflux adriamycin decreased markedly in CIAPIN1 siRNA transfectants, and correlation between CIAPIN1 down regulation and decreased MDR1 transcriptional activity were observed. CIAPIN1 siRNA could significantly down regulate the expression of Bcl-2, and up-regulate the expression of Bax, but not alter the expression of PTEN in gastric cancer cells. These observations suggested that the siRNA constructs of CIAPIN1 we obtained could effectively down-regulate the expression of CIAPIN1 and reverse the resistant phenotype of gastric cancer cells. The further study of the biological functions of CIAPIN1 may be helpful for understanding the mechanisms of multidrug resistance of gastric cancer and developing possible strategies to treat gastric cancer.

Prospective randomized comparison of 1-day versus 3-day application of topical levofloxacin in eliminating conjunctival flora

PURPOSE

To compare efficacy of a 1-day versus 3-day application of topical levofloxacin in reducing ocular surface bacteria.

METHODS

In this prospective randomized controlled trial, 100 volunteer patients (50 per group) were assigned to receive topical 0.5% levofloxacin four times daily for 1 day or 3 days. Conjunctival cultures were obtained prior to (T0) and after the application of antibiotics (T1). Additionally, all patients received topical levofloxacin at 5-minute intervals for three applications (T2), followed by two drops of topical 5% povidone-iodine (T3). Conjunctival cultures were obtained at timepoints T2 and T3.

RESULTS

A 1-day application of topical levofloxacin significantly reduced (p = 0.0004) the number of eyes with positive conjunctival cultures from 41 eyes (82%) to 23 eyes (46%). Similarly, a 3-day application significantly reduced (p = 0.0001) the positive culture rate from 37 eyes (74%) to 17 eyes (34%). Two drops of povidone-iodine further reduced the positive culture rate for both groups to 20% (10 eyes for each group). There was no significant difference in positive culture rate between the 1-day and 3-day groups at T0 (p = 0.4689), T1 (p = 0.3074), T2 (p = 0.6706), or T3 (p = 1.000).

CONCLUSIONS

The application of topical 0.5% levofloxacin for 1 or 3 days significantly reduced the number of eyes with positive conjunctival cultures. The addition of 5% povidone-iodine further eliminated bacteria from the conjunctiva. The application of levofloxacin for 1 day appears to be as effective as a 3-day application.

Modeling of substrate degradation and oxygen consumption in waste composting processes

A multi-component modeling system was developed to simulate substrate degradation and oxygen consumption in waste composting processes. Levels of soluble substrate (Ss), insoluble substrate (Si), active biomass (X), inert material, moisture, temperature, and oxygen concentration were considered as state variables. The relationships among these variables were also incorporated within the modeling framework. Three conversion reactions, including growth of aerobic biomass, decay of aerobic biomass, and solubilisation of insoluble substrate, were considered in the simulation system. The modeling inputs included temperature, moisture, oxygen concentration, and initial conditions of the state variables, while the outputs included oxygen uptake accumulation (OUA), oxygen uptake rate (OUR), Ss, Si, and X for representing the substrate degradation and oxygen consumption status. The effectiveness of the developed model was demonstrated through its application to a case study in a 30L vessel over 200h. Through verification-based composting experiments, it was shown that the modeling solutions were consistent with the experimental results with an acceptable accuracy level. Sensitivity analyses of the model showed that an increased maximum microbial growth rate would result in raised OUA, OUR, Ss, and X levels; a decreased biomass decay rate constant would help enhance the composting process. Moreover, variations in the maximum growth rate would affect the composting process more significantly than those of the biomass decay rate constant.

Downregulation of mu opioid receptor by RNA interference in the ventral tegmental area reduces ethanol consumption in mice

Pharmacological and genetic studies have implicated the mu opioid receptor (MOR) in the regulation of ethanol intake in animal models and humans. Non-specific antagonists of opioid receptors have been shown to affect ethanol consumption when infused directly into the ventral tegmental area (VTA) of rats. However, administration of MOR-selective antagonists into the VTA has yielded mixed results. We used RNA interference (RNAi) to specifically decrease levels of MOR messenger RNA in the VTA of mice and examined the effect on ethanol consumption in a two-bottle choice paradigm. Mice were injected in the VTA with lentivirus expressing either a small hairpin RNA (shRNA) targeting MOR or a control shRNA. One week after virus injection, mice were examined for ethanol consumption in a two-bottle choice experiment with increasing concentrations of ethanol over the course of 1 month. Expression of an shRNA targeting MOR in the VTA led to a significant reduction in ethanol consumption. These results strengthen the hypothesis that MOR in the VTA is one of the key brain substrates mediating alcohol consumption. The RNAi combined with lentiviral delivery can be used successfully in brain to effect a sustained reduction in expression of specific genes for behavioral analysis.

Acupuncture for Bell's palsy

BACKGROUND

Bell's palsy or idiopathic facial palsy is an acute facial paralysis due to inflammation of the facial nerve. A number of studies published in China have suggested acupuncture is beneficial for facial palsy.

OBJECTIVES

The objective of this review was to examine the efficacy of acupuncture in hastening recovery and reducing long-term morbidity from Bell's palsy.

SEARCH STRATEGY

We searched the Cochrane Neuromuscular Disease Group Trials Register, MEDLINE (January 1966 to April 2006), EMBASE (January 1980 to April 2006), LILACS (from January 1982 to April 2006) and the Chinese Biomedical Retrieval System (January 1978 to April 2006) for randomised controlled trials using 'Bell's palsy' and its synonyms, 'idiopathic facial paralysis' or 'facial palsy' as well as search terms including 'acupuncture'. Chinese journals in which we thought we might find randomised controlled trials or controlled clinical trials relevant to our study were handsearched. We reviewed the bibliographies of the randomised trials and contacted the authors and known experts in the field to identify additional published or unpublished data.

SELECTION CRITERIA

We included all randomised or quasi-randomised controlled trials involving acupuncture in the treatment of Bell's palsy irrespective of any language restrictions.

DATA COLLECTION AND ANALYSIS

Two review authors identified potential articles from the literature search and extracted data independently using a data extraction form. The assessment of methodological quality included allocation concealment, patient blinding, differences at baseline of the experimental groups and completeness of follow-up. Two review authors assessed quality independently. All disagreements were resolved by discussion between the review authors.

MAIN RESULTS

Six studies including a total of 537 participants met the inclusion criteria. Five of them used acupuncture while another one used acupuncture combined with drugs. No trials reported on the outcomes specified for this review. Harmful side effects were not reported in any of the trials. Flaws in study design or reporting (particularly uncertain allocation concealment and substantial loss to follow-up) and clinical differences between trials prevented conclusions about the efficacy of acupuncture.

AUTHORS' CONCLUSIONS

The quality of the included trials was inadequate to allow any conclusion about the efficacy of acupuncture. More research with high quality trials is needed.

Enhanced nitric oxide-mediated chemoreceptor inhibition and altered cyclic GMP signaling in rat carotid body following chronic hypoxia

Multiple studies have shown that chronic hypoxia (CH) elicits a time-dependent upregulation of carotid body chemoreceptor sensitivity in mammals. In the present study, we demonstrate that enhanced excitation is accompanied by a parallel increase of nitric oxide (NO)-dependent inhibition, which acts via a CH-induced modification of the normal mechanism in O(2)-sensitive type I cells. The NO synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), elicits a progressively larger increase in carotid sinus nerve (CSN) chemoreceptor activity following incremental increases in CH exposure lasting 1-16 days. The inhibitory effect of the NO donor, S-nitroso-N-acetyl-penicillamine (SNAP), on CSN activity is enhanced following CH. However, the activation of soluble guanylate cyclase (sGC) by SNAP, assessed via production of cGMP, is impaired, along with decreased expression of sGC mRNA transcript. Inhibition of hypoxia-evoked Ca(2+) responses by SNAP is mediated via a cGMP/protein kinase G (PKG)-dependent mechanism in normal type I cells that is sensitive to the PKG inhibitor KT-5823, but following CH, inhibitory responses are minimally sensitive to PKG inhibition. The data are consistent with the hypothesis that CH hampers cGMP-mediated inhibition of type I cells in favor of an alternative mechanism.

A novel DFNA5 mutation, IVS8+4 A>G, in the splice donor site of intron 8 causes late-onset non-syndromic hearing loss in a Chinese family

We report here the clinical, genetic, and molecular characteristics of a large Chinese family exhibiting non-syndromic, late-onset autosomal dominant sensorineural hearing loss. Clinical evaluation revealed variable phenotypes of hearing loss in terms of severity and age-at-onset of disease in these subjects. Genome-wide linkage analysis mapped the disease gene to the DFNA5 locus with a maximum two-point log odds score of 5.39 at [theta] = 0 for marker D7S2457. DNA sequencing of DFNA5 revealed a novel heterozygous IVS8+4 A>G substitution in the splice donor site of intron 8. Reverse transcriptase-polymerase chain reaction (RT-PCR) showed skipping of exon 8 in the mutant transcript. This mutation faithfully cosegregated with hearing loss in the family. In addition, the mutation was absent in 100 unrelated control DNA samples of Chinese origin. The IVS8+4 A>G mutation is predicted to create a shift in the reading frame and introduce a stop codon at position 372, thereby resulting in a prematurely truncated DFNA5 protein. Up to date, a total of four mutations in DFNA5 have been reported to lead to hearing impairment, all of them result in skipping of exon 8 at the mRNA level. Our findings provide further support for the hypothesis that DFNA5-associated hearing loss is caused by a very specific gain-of-function mutation.

Antibody-targeted vaccines

The specificity and high affinity binding of antibodies provides these molecules with ideal properties for delivering a payload to target cells. This concept has been commercialized for cancer therapies using toxin- or radionucleotide-conjugated antibodies that are designed to selectively deliver cytotoxic molecules to cancer cells. Exploiting the same effective characteristics of antibodies, antibody-targeted vaccines (ATV) are designed to deliver disease-specific antigens to professional antigen-presenting cells (APCs), thus enabling the host's immune system to recognize and eliminate malignant or infected cells through adaptive immunity. The concept of ATVs has been in development for many years, and recently has entered clinical trials. Early studies with ATVs focused on the ability to induce humoral immunity in the absence of adjuvants. More recently, ATVs targeted to C-type lectin receptors have been exploited for induction of potent helper and cytolytic T-cell responses. To maximize their stimulatory capacity, the ATVs are being evaluated with a variety of adjuvants or other immunostimulatory agents. In the absence of co-administered immunostimulatory signals, APC-targeting can induce antigen-specific tolerance and, thus, may also be exploited in developing specific treatments for autoimmune and allergic diseases, or for preventing transplant rejection. The successful clinical application of this new class of antibody-based products will clearly depend on using appropriate combinations with other strategies that influence the immune system.

Pregnancy and perinatal health in Inner Mongolia, China, 1996-1999

OBJECTIVE

To obtain descriptive measures of maternal and perinatal health in the Ba Men Region of Inner Mongolia, China.

METHODS

Data collected from the Examination Chart for Pregnant Women for approximately 22,000 pregnancies in a three-county area of Inner Mongolia, China from December 1, 1996 through December 31, 1999 were analyzed for maternal, perinatal, and neonatal outcomes.

RESULTS

Compared to selected developing countries, a higher percentage of women (99%) in this region received at least one prenatal care visit. This region was also characterized by a low percentage of low birthweight (<2.5 kg) infants (1%) and neonatal mortality rate (5 deaths per 1000 live births).

CONCLUSIONS

Maternal and neonatal health outcomes in this region of Inner Mongolia were better than those in selected developing countries.

Useful indicators for performing renal biopsy in adult patients with isolated microscopic haematuria

Among adult patients with isolated microscopic haematuria (IMH) which is defined as persistent microscopic haematuria but without proteinura, hypertension, renal insufficiency, urinary tract infection or structural abnormality of the urinary tract, some patients have chronic glomerulonephritis (CGN), in whom early diagnosis by renal biopsy is beneficial to timely intervention. Nevertheless, a considerable number of patients with optimistic prognosis [e.g. thin basement membrane nephropathy (TBMN)] undergo invasive and needless renal biopsy. Indicators for weighing the necessity of renal biopsy would be clinically significant. To investigate the value of urinary albumin/creatinine ratio (UACR), serum IgA level, serum C3 level and serum IgA to C3 ratio in predicting the necessity of renal biopsy for adult patients with IMH, 216 patients were studied retrospectively. Patients were divided into: (CGN group, n=137), (TBMN group, n=56) and normal biopsy (normal group, n=23). Of all patients, 131 (61%) evidenced microalbuminuria (UACR=30-299 mg/g) and 85 (39%) had normoalbuminuria (UACR<30 mg/g). The mean value of UACR in CGN group was higher (96+/-17 mg/g) compared with that in TBMN (20+/-4 mg/g, p<0.01) or normal (18+/-3 mg/g, p<0.01) group. The mean values of serum IgA and serum IgA/C3 ratio in patients with IgA nephropathy (IgAN) were significantly higher than those with non-IgAN (380+/-103:217+/-99 mg/dl, p<0.01; 4.5+/-1.2 : 2.4+/-0.9, p<0.01). The odds ratio for distinguishing IgAN from non-IgAN was significantly correlated with serum IgA level and serum IgA to C3 ratio. For adult patients with IMH, UACR, serum IgA level and serum IgA to C3 ratio are non-invasive markers for predicting the necessity of renal biopsy.

Control of mesothelin-expressing ovarian cancer using adoptive transfer of mesothelin peptide-specific CD8+ T cells

Cancer immunotherapy targeting mesothelin represents a potentially plausible approach for the control of ovarian cancer as most ovarian cancers express high levels of mesothelin. In the current study, we created a mesothelin-positive luciferase-expressing ovarian cancer model, MOSEC/luc. This luciferase-expressing tumor model allowed us to quantitate tumor distribution and tumor load in tumor-challenged mice using a non-invasive bioluminescence imaging system. In addition, we identified an H-2D(b)-restricted mesothelin peptide-specific cytotoxic T-lymphocyte (CTL) epitope (amino acid (aa) 406-414) that was endogenously processed and presented by MOSEC/luc tumor cells. We showed that adoptive transfer of mesothelin peptide (aa406-414)-specific CD8(+) T cells led to the control of MOSEC/luc tumor cells. The MOSEC/luc tumor model and the newly identified H-2D(b)-restricted murine mesothelin-specific CTL epitope (aa406-414) will be very useful for the development of immunotherapy for ovarian cancer as well as for the development of quantitative CD8(+) T cell-mediated immunological assays.

Glomerulus-specific mRNA transcripts and proteins identified through kidney expressed sequence tag database analysis

The kidney glomerulus plays a crucial role in blood filtration but the molecular composition and physiology of the glomerulus is not well understood. We previously constructed and large-scale sequenced four mouse glomerular expressed sequence tag (EST) libraries from newborn and adult mouse glomeruli. Here, we compared glomerular EST profiles with whole kidney EST profiles, thereby identifying 497 transcripts corresponding to UniGene clusters that were glomerulus-enriched, that is expressed more abundantly in glomeruli than in whole kidney. These include several known protein-coding glomerulus-specific transcripts critical for glomerulus development and function, but also a large number of gene transcripts, which have not previously been shown to be expressed in the glomerulus, or implicated in glomerular functions. We used in situ hybridization to demonstrate glomerulus-specific RNA expression for six novel glomerular genes and the public Human Protein Atlas to verify glomerular protein expression for another two. The higher mRNA abundance for the eight genes in glomeruli compared with whole kidney was also verified by Taqman quantitative polymerase chain reaction. We surmise that the further characterization of these genes and proteins will increase our understanding of glomerular development and physiology.