What does the nature of the MECP2 mutation tell us about parental origin and recurrence risk in Rett syndrome?

The MECP2 mutations occurring in the severe neurological disorder Rett syndrome are predominantly de novo, with rare familial cases. The aims of this study were to provide a precise estimate of the parental origin of MECP2 mutations using a large Chinese sample and to assess whether parental origin varied by mutation type. The parental origin was paternal in 84/88 [95.5%, (95% confidence interval 88.77-98.75)] of sporadic Chinese cases. However, in a pooled sample including data from the literature the spectrum of mutations occurring on maternally and paternally derived chromosomes differed significantly. The excess we found of 'single base pair gains or losses' on maternally derived MECP2 gene alleles suggests that this mutational category is associated with an elevated risk of gonadal mosaicism, which has implications for genetic counseling.

Phosphorus release and uptake during start-up of a covered and non-aerated sequencing batch reactor with separate feeding of VFA and sulfate

This study explored a sulfur cycle-associated biological phosphorus (P) removal process in a covered and non-aerated sequencing batch reactor (SBR) fed with volatile fatty acid (VFA) and sulfate separately. During the 60-day start-up, both phosphate release and uptake rates increased, while poly-phosphate cyclically increased and decreased accordingly. The P-release and P-uptake rates were associated with VFA uptake and sulfate reduction. The average ratio of potassium to phosphate during the P-uptake and P-release was also determined to be 0.29-0.31 mol K/mol P, which is close to a reported value (0.33) for biological phosphorus removal. All this evidence confirmed there was biological P removal in this reactor, in which metabolism could be different from conventional biological P removal.

Eight polymorphic microsatellite markers for the spotted babylon, Babylonia areolata (Buccinidae)

The spotted babylon, Babylonia areolata, is one of the most extensively cultured marine mollusks in southeast Asia. Eight polymorphic microsatellite markers were developed for this species, from a microsatellite-enriched library. These markers, characterized in 32 individuals from a hatchery population, were polymorphic, with allele numbers ranging from 6 to 18 per locus, expected and observed heterozygosities ranging from 0.68 to 0.94 and 0.56 to 0.81, respectively. One locus (HUBA09) showed significant deviation from Hardy-Weinberg equilibrium, probably due to the presence of null alleles. These microsatellite loci should be useful for future population genetic studies and marker-assisted breeding in this species.

P1-13-04: Phase II Study of Topical Imiquimod and Abraxane for Treatment of Breast Cancer Cutaneous Metastases

Background: Breast cancer (BC) cutaneous lesions can present as local chest wall recurrence or isolated sites of metastatic disease. Current treatments with full thickness chest wall resection, radiation therapy and chemotherapy are not curative; and have significant morbidity and poor overall response rates. Combining local immunomodulation and systemic chemotherapy may be more effective in treating cutaneous disease. Topical imiquimod (IMQ), a TLR-7 agonist, has shown clinical activity against cutaneous metastasis. Pre-clinical studies have shown IMQ to stimulate Th1 cytokine secretion and up-regulate immune co-stimulatory molecules at the tumor site; resulting in augmented tumor specific T cell immunity and tumor growth inhibition. Use of paclitaxel in BC, has demonstrated immunostimulatory effects of increased serum IFN-γ and enhanced NK/LAK cell activity. Abraxane (albumin-bound paclitaxel) may be used in conjunction with IMQ as steroid pre-treatment is not required. We hypothesize the immune effects of Abraxane may synergize and augment the IMQ anti-tumor effects, resulting in greater clinical response. A phase II single-arm study of chemoimmunotherapy with topical IMQ and Abraxane was initiated to determine its safety and therapeutic efficacy; and examine its effect on augmenting endogenous tumor specific immunity and inducing tumor molecular alterations associated with inhibition of tumor growth and/or common pathways of BC immune escape.

Materials and Methods: Up to 15 BC patients with cutaneous lesions no longer amenable to standard therapy are enrolled and receive 3 treatment cycles. A treatment cycle consist of topical 5% IMQ to target lesions 4 days/week (wk.) and Abraxane 100 mg/m2 on Days 1, 8, 15 every 28 Days. Toxicity is evaluated per CTCAE v3.0 on Days 1, 8, 15 of each cycle and wks. 13, 16, 20, 24. Target lesion antitumor activity is assessed per modified WHO criteria (Complete response (CR); Partial response (PR); Stable disease (SD); Progressive disease (PD)) at baseline, wks. 4, 8, 12, 16, 20, 24. 2-mm target lesion skin biopsies are obtained pre-and post-treatment for histologic analysis and RT-PCR analysis of a 7 IFN-related gene signature associated with tumor inhibition. Immunity to HER2, IGFBP-2, TOPO-IIα, p53 and serum TGF-β levels are evaluated at baseline and wks. 12, 24 with IFN-γ ELISPOT and ELISA, respectively.

Results: 10 patients have been enrolled. Median (range) values include: age, 54 years (48-92), time from metastatic diagnosis, 134 months (58-728), prior chemotherapy regimens, 5 (2-10). 5/10 patients had received prior local therapy, e.g., radiation. 5/10, 4/10, and 2/10 patients had triple negative, HER2+ and ER+/PR+ tumors, respectively. In 5 patients completing 3 treatment cycles, overall response rate (ORR) = 100% (3 CR, 2 PR). In the 5 patients who completed 1–2 treatment cycles, ORR = 80% (2 PR, 2 SD, 1 PD). Treatment related toxicity is primarily grade I/II neutropenia, anemia; grade I skin toxicity. Immunologic analyses are ongoing and will be presented with completed clinical data on all patients.

Conclusions: Chemoimmunotherapy with topical IMQ and Abraxane is well-tolerated and shows excellent clinical efficacy in treating metastatic cutaneous lesions in heavily pretreated BC patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-13-04.

The increased expression of metabotropic glutamate receptor 5 in subventricular zone neural progenitor cells and enhanced neurogenesis in a rat model of intracerebral hemorrhage

The metabotropic glutamate receptor 5 (mGluR5) is closely relative to the proliferation, survival, and differentiation of neural progenitor cells (NPCs). This study primarily examined the mGluR5 expression of NPCs in subventricular zone (SVZ) and the effects of mGluR5 on neurogenesis to intracerebral hemorrhage (ICH) rat. The experiment was designated as the following: (1) The ICH model was established by collagenase infusion into the right striatum of the rats, and the brain tissue was collected to assess the expression of mGluR5 in SVZ NPCs. (2) The rat brains were sampled for immunostaining of doublecortin (DCX) and 5-bromo-2'-deoxyuridine (BrdU) to examine the effects of the (R,S)-2-chloro-5-hydroxyphenylglycine (CHPG) on neurogenesis. (3) Behavioral testing was carried out to evaluate the effects of CHPG on neurofunctional recovery. The results of Western blot analysis showed that mGluR5 levels in the ipsilateral SVZ increased as early as at 3 days after ICH, peaked at 14 days. The change of mGluR5 mRNA level in the ipsilateral SVZ was generally similar to the pattern of Western blot analysis. The immunostaining also demonstrated that some nestin-positive cells were co-expressed with mGluR5. The injection of CHPG into ipsilateral ventricle increased DCX levels both in the ipsilateral striatum (STR) and the peri-lesion area of the striatum (PLA). Meanwhile, a significant difference in behavioral score was presented at 28 days after ICH between the CHPG-treated rats and the vehicle-treated or the non-treated rats. Our results demonstrated for the first time that the increased expression of mGluR5 in SVZ NPCs occurred in ICH rat. The CHPG promoted the neurogenesis and improved neurofunctional symptom induced by ICH. These results suggested that the increased expression of mGluR5 on NPCs in SVZ may play an important role in neurogenesis in ICH rat.

Relationships of percent body fat and percent trunk fat with bone mineral density among Chinese, black, and white subjects

We examined ethnic difference in the association of body fat and trunk fat with bone mineral density (BMD) among Chinese, white, and black subjects. We found that, with greater body and trunk fat, both white and black subjects were more likely to have a low BMD than Chinese subjects.

INTRODUCTION

Ethnic differences in body fat, abdominal fat distribution, and BMD have been found in previous studies between Chinese and white subjects. However, the associations of body fat and abdominal fat distribution with BMD have not been studied, and whether the ethnic differences have an effect on these associations is unclear.

METHODS

We evaluated 1,147 subjects aged ≥ 18 years (805 Chinese, 193 whites, and 149 blacks). Percent body fat (%BF), percent trunk fat (%TF), and total and regional BMD including that of head, arm, leg, trunk, rib, spine, and pelvis were measured by dual-energy X-ray absorptiometry. Linear regression models were developed to test the association of ethnicity, %BF, and interaction between ethnicity and %BF with BMD. The models were repeated again, replacing %BF with %TF.

RESULTS

Chinese subjects showed lower BMD in total and most regions compared with black and white subjects; however, these differences were eliminated between Chinese and whites within both sexes and between Chinese and black men when age, weight, height, and %BF were added. %BF and %TF were negatively associated with most regional body BMD. The interactions between %BF, %TF, and ethnicity were found in most regional body BMD among Chinese, white, and black subjects for both men and women.

CONCLUSION

Both %BF and %TF have negative associations with BMD. With greater accumulation of %BF and %TF, both white and black subjects may experience a higher risk of low BMD than Chinese subjects.

Increment of 30-min post-challenge plasma glucose is associated with urine albumin excretion in men with normal glucose regulation

AIMS

The overwhelming majority of subjects with normal glucose regulation have the highest plasma glucose concentration at 30 minutes during oral glucose tolerance. We aimed to examine the association between increment of 30-min post-challenge glucose and albuminuria in participants with normal glucose regulation.

METHODS

A population-based cross-sectional study was conducted in six communities in Shanghai between 2007 and 2008. A total of 3508 subjects with normal glucose regulation had complete data and were enrolled into the analysis. Among the selected subjects, only 1525 individuals (581 men, 944 women) were examined for their serum insulin levels. We assessed post-challenge blood glucose and insulin at 0, 30 and 120 min, urinary albumin and creatinine. The 30-min post-challenge glucose increment (Δ) was calculated as 30-min post-challenge glucose minus fasting plasma glucose, and albumin/creatinine ratio was used to reflect urinary albumin excretion.

RESULTS

Multivariable logistic regression analysis revealed that the Δ30-min post-challenge glucose was independently associated with increased albumin/creatinine ratio in men with normal glucose regulation (OR = 1.08, P = 0.025), but not in women. Furthermore, multivariable linear regression analysis revealed that early-phase glucose disposition index was the main factor responsible for Δ30-min post-challenge glucose and explained 14-20% of the variance of Δ30-min post-challenge glucose in the two subgroups (P < 0.05). Notably, men had higher Δ30-min post-challenge glucose and lower early-phase glucose disposition index than women (all P < 0.001).

CONCLUSIONS

The 30-min post-challenge plasma glucose increment is associated with urine albumin excretion in men with normal glucose regulation.

Vertex-deleted subgraphs and regular factors from regular graph

Let k, m, and r be three integers such that 2≤k≤m≤r. Let G be a 2r-regular, 2m-edge-connected graph of odd order. We obtain some sufficient conditions for G-v to contain a k-factor for all v∈V(G).

Simvastatin exerts favourable effects on neointimal formation in a mouse model of vein graft

BACKGROUND

Simvastatin inhibits human saphenous vein neointima formation in human saphenous vein organ cultures. However, it is not known if simvastatin actually inhibits vein graft intima hyperplasia in vivo, and the underlying mechanisms behind that. In this study, we used a murine vein graft model to address these issues.

METHODS AND RESULTS

Vein grafting was performed among C57BL/6 J mice treated with low-dose (2 mg kg(-1)) or high-dose (20 mg kg(-1)) simvastatin or vehicle subcutaneously 72 h before and then daily after surgery. As compared to the vehicle, simvastatin dose-dependently significantly inhibited vein graft intima hyperplasia 4 weeks after surgeries. Immunohistochemistry studies suggested that vein graft neointima was mainly composed of vascular smooth muscle cells (VSMCs), and the rate of proliferating cell nuclear antigen (PCNA)-positive cells in the intima of vein grafts was significantly lower in simvastatin-treated groups than in control group. We isolated VSMC from mouse vena cava, simvastatin significantly reduced VSMC proliferation, and platelet-derived growth factor (PDGF)-induced VSMC migration in a dose-dependent manner.

CONCLUSION

Simvastatin inhibits neointima formation of mouse vein graft under normocholesterolaemic condition in vivo, the mechanisms might be associated with inhibitory effects of simvastatin on VSMC proliferation and migration.