KCNJ11 Lys23Glu and TCF7L2 rs290487(C/T) polymorphisms affect therapeutic efficacy of repaglinide in Chinese patients with type 2 diabetes

This study showed that the polymorphisms KCNJ11 Lys23Glu and TCF7L2 rs290487(C/T) are associated with a heightened risk of developing type 2 diabetes mellitus (T2DM). We also explored the effects of these polymorphisms on the efficacy of repaglinide therapy in Chinese patients with T2DM. A total of 259 patients with T2DM and 188 healthy controls were genotyped. Forty patients with various genotypes were randomly selected to undergo an 8-week repaglinide treatment regimen. Patients with the G allele of the KCNJ11 Lys23Glu polymorphism showed higher levels of fasting plasma glucose (FPG) and postprandial plasma glucose (PPG) (P < 0.05). After repaglinide treatment, patients with the GA or AA genotype showed higher levels of FPG, PPG, and glycated hemoglobin (HbA(1c)) compared with patients with the GG genotype (P < 0.05). Patients with the C allele of TCF7L2 rs290487(C/T) had higher total cholesterol levels and lower body mass index (BMI) (P < 0.05). In patients with the TT genotype, the drug showed better efficacy with respect to levels of fasting insulin, triglycerides, and low-density lipoprotein cholesterol (LDL-c) than in patients with the CC or CT genotype (P < 0.05). The KCNJ11 and TCF7L2 polymorphisms were associated with repaglinide efficacy.

Phase modulation with micromachined resonant mirrors for low-coherence fiber-tip pressure sensors

This letter presents a simple phase modulation scheme for interrogation of low-coherence interferometry based fiber-tip pressure sensors to enable real-time monitoring and miniaturization of the entire sensor system. The key idea is to introduce a sinusoidal modulation signal and retrieve the sensing cavity length change using a simple algorithm, without resorting to any time information. In experiments, phase modulation has been achieved by using a silicon-micromachined tunable Fabry-Pérot interferometer, which is integrated with a light source and a photodiode onto a single chip. Compared with the conventional interrogation methods, this scheme possesses the merits of being less susceptible to disturbance, easy control and easy miniaturization, making it particularly suitable for sensing in constrained spaces and harsh environments.

Improved, low-cost methods for pancreatic islet purification in rats

OBJECTIVE

Density gradient separation of islets from exocrine tissue is usually performed using Ficoll. However, this reagent significantly increases the cost of isolation. The aim of the present study was to investigate the effects on islet preparations of purification methods using Lymphoprep and Iodixanol (OptiPrep) density gradients.

METHODS

Pancreata were procured from 46 Wistar rats, loaded with collagenase V (Sigma), and mechanically dissociated using standard procedures. After the digestion phase, the islets purified by 3 methods-Ficoll, Lymphoprep, and Iodixanol (OptiPrep)-were assessed for yields, purity, morphology, and in vitro function.

RESULT

We expressed the yields as islet equivalents (IEQ, diameter standardizing to 150 microm), showing no significant differences. Compared with the Ficoll group, the purity was significantly higher in the Lymphoprep (P = .005) and Iodixanol (OptiPrep) groups (P = .011). While the viability was >90% in all 3 groups, the viability in the Lymphoprep Group and OptiPrep groups was significantly higher than that of the Ficoll group (P < .001). In vitro islet function did not differ among the 3 experimental groups.

CONCLUSION

Lymphoprep and Iodixanol were as effective as Ficoll in terms of islet yield and in vitro function. High-purity and high-viability islet cells were obtained using improved Lymphoprep-based or Iodixanol (OptiPrep)-based density gradient methods, potential low-cost substitutes for Ficoll.

<i>Tropomodulin 1 (TMOD1)</i> is associated with lean meat growth and meat quality in the pig (Brief Report)

Abstract. Tropomodulin 1 (TMOD1) is a member of the tropomodulin family, which are highly conserved capping proteins of the pointed ends of the erythrocyte membrane and sarcomeric actin filaments. Tropomodulins are involved in the architecture of the sarcomere in muscle cells and the membrane skeleton in nonmuscle cells (COLUCCIO et al. 1994, GREGORIO et al. 1995). TMOD1 is predominantly expressed in vertebrate cardiac muscle and slow twitch muscle fibers, and it binds to one end of tropomyosin (TM) that plays important roles in regulating the function of actin filament (FISCHER et al. 2003, GUNNING et al. 2008). Here we identified a single nucleotide polymorphism (SNP) in the porcine TMOD1 gene and further analyzed the effects of this gene on the lean meat growth, meat quality and other related traits in pigs.

A phase II study of pemetrexed as second-line chemotherapy for the treatment of metastatic castrate-resistant prostate cancer (CRPC); Hoosier Oncology Group GU03-67

BACKGROUND

No standard therapy exists for post-docetaxel castrate-resistant prostate cancer (CRPC) patients. This trial aimed to determine the safety and efficacy of pemetrexed in post-docetaxel CRPC patients.

MATERIALS AND METHODS

CRPC patients with progression after docetaxel (Taxotere) therapy received pemetrexed (500 mg/m2) i.v. every 3 weeks. The primary end point was prostate-specific antigen (PSA) response. A pharmacogenetic analysis of the reduced folate carrier-1 gene (RFC1) G80A polymorphism was also carried out.

RESULTS

Forty-nine patients were enrolled: median age 68 years, median baseline PSA 72 ng/ml, and median Karnofsky performance status of 90. Grade 3 or 4 toxicity occurred in 20 (43%) and four patients (8%), respectively. Confirmed >50% PSA decline occurred in four patients (8%), stable PSA lasting at least 12 weeks in 10 patients (20%). A significant relationship was observed between time from prior docetaxel therapy and overall survival. Pharmacogenetic analyses of RFC1 G80A genotype frequencies showed no relationship between genotypes and clinical efficacy.

CONCLUSIONS

Pemetrexed treatment of CRPC patients after docetaxel therapy was associated with only modest clinical activity. Further investigation of pemetrexed as a single agent in a nonenriched CRPC population is unlikely to add significant clinical benefit over that seen with traditional second-line chemotherapy agents such as mitoxantrone.

Improving auscultatory blood pressure measurement with electronic and computer technology: the visual auscultation method

BACKGROUND

The auscultatory method is used as the reference standard in all prevalent protocols for validation of noninvasive blood pressure measuring devices, and a validation study is essentially based on the comparison between the device and observer measurements. Thus, the objectivity and accuracy of observer measurements are crucial to the validation result.

METHODS

To provide observers with more objective information about an auscultatory measurement so that sufficient information to make measurements with greater potential objectivity and accuracy can be available, a computerized data acquisition and analysis system has been developed. It cannot only acquire and store Korotkoff sound, cuff pressure, and oscillometric pulse signals, as well as the sphygmomanometer image, but it also can display the waveforms of the three signals and the sphygmomanometer video while playing the synchronous Korotkoff sounds. With this system, observers can make their measurements via the visual auscultation method, that is to say, by watching those waveforms, instead of the sphygmomanometer, while listening for synchronized Korotkoff sounds. The system was validated according to the International Protocol (IP).

RESULTS

The result showed that all the differences between system measurements by the visual auscultation method and observer measurements by the conventional auscultatory method were within 4 mm Hg.

CONCLUSIONS

The visual auscultation method achieved a high degree of accuracy, and human observers can be replaced by the system in the validation study of blood pressure measuring devices.

How well do questionnaires perform compared with physical examination in detecting flexural eczema? Findings from the International Study of Asthma and Allergies in Childhood (ISAAC) Phase Two

BACKGROUND

Questionnaires are widely used in epidemiological studies to measure eczema symptom prevalence, but there are concerns regarding their accuracy if used as a diagnostic tool.

OBJECTIVES

To compare the performance of a validated eczema symptom questionnaire and a standardized skin examination protocol employed in the second phase of the International Study of Asthma and Allergies in Childhood (ISAAC).

METHODS

A total of 30,358 schoolchildren aged 8-12 years from 18 countries were examined for flexural eczema. Parents also completed an eczema symptom questionnaire. We compared prevalence estimates at the population level based on the questionnaire vs. physical examination. We also compared the skin examination and the ISAAC questionnaire in making a diagnosis of flexural eczema.

RESULTS

The point prevalences for flexural eczema at centre level based on a single examination were lower than the questionnaire-based 12-month period prevalences (mean centre prevalence 3.9% vs. 9.4%). Correlation between prevalences of both outcome measures was high (r = 0.77, P < 0.001). At the individual level, questionnaire-derived symptoms of 'persistent flexural eczema in the past 12 months' missed < 10% of cases of flexural eczema detected on physical examination. However, between 33% and 100% of questionnaire-based symptoms of 'persistent flexural eczema in the past 12 months' were not confirmed on examination.

CONCLUSIONS

ISAAC questionnaire-derived symptom prevalences are sufficiently precise for comparisons between populations. Where diagnostic precision at the individual level is important, questionnaires should be validated and potentially modified in those populations beforehand, or a standardized skin examination protocol should be used.

Preoperative cetuximab and radiation (XRT) for patients (pts) with surgically resectable esophageal and gastroesophageal junction (GEJ) carcinomas: A pilot study from the Hoosier Oncology Group and the University of Texas Southwestern

4557

Background: Pre-operative chemoradiotherapy (CRT) followed by surgical resection is a standard treatment option for pts with resectable esophageal or GE junction (GEJ) carcinomas (CA). Cetuximab, when combined with XRT is effective treatment for locally advanced cancers of the head and neck. We conducted this study to evaluate this regimen in pts with esophageal and GEJ CA. Methods: This is a single arm, open label pilot study combining cetuximab with XRT for pts with resectable esophageal and GEJ CA. The primary objective is to determine the pathologic complete response rate (pCR) (null hypothesis: p=0.20; alternative hypothesis: p=0.35) and determine the feasibility and toxicity of this regimen when given prior to esophagectomy. Key eligibility criteria are: squamous cell (SC)or adenoCA of the esophagus or GEJ, ECOG PS 0–2, clinical stage II -IVa, and eligible for esophagectomy. Pts received a loading dose of cetuximab at 400mg/m2 2 weeks prior to XRT, then weekly at 250 mg/m2 starting one week prior to XRT until completion of 50.4 Gy XRT. After satisfactory recovery, pts had esophagectomy. Results: Patient characteristics (n=40): median age 65 years (range, 54–82); 92% male; PS 0/1 63%/32%; esophageal/GEJ 65%/35%; adenoCA/SC 78%/22%; 36 pts have completed cetuximab and radiation and 26 pts have undergone esophagectomy. Of the 26 pts that have undergone esophagectomy, 13 obtained a pCR. 5/13 SC had pCR and 8/13 adenoCA had pCR. 10 pts did not undergo surgery for various reasons including disease progression (n=7), AE unrelated to treatment (n=2), and personal decision to forgo esophagectomy (n=1). 4 patients are still completing cetuximab/XRT. The most common G3 adverse event was rash (56%). Other G3 toxicities were infrequent and included dysphagia (6%), infection (6%), and GI bleed (3%). There have been no treatment or surgery related deaths. Conclusions: Cetuximab and XRT results in pCR's in pts with esophageal and GEJ CA (rate of pCR 13/36), including patients with either SC or adenoCA histologies. G3/4 toxicities, including dysphagia were generally uncommon. Further study of this combination prior to esophagectomy is warranted.

[Table: see text]

Erlotinib and bevacizumab in chemotherapy-naive performance status 2 patients with advanced non-small cell lung cancer

e19082

Background: Poor performance status is a negative prognostic variable for survival and a risk for increased toxicities with standard chemotherapy. A phase 2 study combining erlotinib (E) and bevacizumab (B) demonstrated encouraging efficacy in the treatment of recurrent NSCLC with acceptable toxicity. We, therefore, tested this regimen in untreated PS 2 patients with advanced NSCLC. Methods: Single-arm phase 2 trial in treatment-naïve patients with advanced non-squamous NSCLC and either a PS of 2 or age >75. Only patients eligible for bevacizumab per label were allowed onto study. Patients received E 150 mg orally daily and B 15 mg/kg IV on day 1 every 21 days for up to 6 cycles. The primary end-point was the rate of non progressive disease at 4 months (alternative hypothesis P>60%). Other end-points included overall survival, progression free survival (PFS), toxicity evaluations and patient-reported PS (PRPS) measures. Results: 25 patients were enrolled. Patient characteristics: 56% female, median age 77 years (range: 52–90); 88% stage IV; 92% were PS 2; 20% were never or remote smokers (> 30 years) The PRPS was 1, 2, 3 in 32%, 52%, 8% respectively with data on 2 patients missing. The rate of non-progression at 4 months was 40%; overall best response: 5% PR, 40% SD, 50% PD and 5% unevaluable; median PFS 2.6 months, 95% CI (1.3–5.1); MST 5.8 months, 95% CI (3.8- 8.7). 2 patients had G3 rash. G3 diarrhea, G3 hemorrhage, G3 proteinuria, G3 duodenal ulcer and G3 pneumonitis each developed in one patient. Conclusions: E + B is an active regimen with an acceptable toxicity profile; however, this study did not meet its’ primary endpoint. Further study of this combination will not be pursued in the Hoosier Oncology Group for this patient population.

[Table: see text]

Translational proof of mechanism (PoM) for sorafenib with bevacizumab: Endpoint analysis and clinical activity

3574

Background: We hypothesized that molecular targeting of tumor and its microenvironment with rational combination therapy would yield improved outcome. Bevacizumab (B) is a monocolonal antibody to vascular endothelial growth factor (VEGFF) and sorafenib (S) is a small molecule inhibitor of the VEGF receptor-2 and RAF-kinase.We have previously reported that S 200mg bid with B 5mg/kg q2wk resulted in partial responses and prolonged disease stabilization (ovarian cancers, renal cell cancer, leiomyosarcoma). Serial tumor biopsies were obtained for translational proof of mechanism analysis. Methods: Percutaneous core biopsies of metastatic sites were obtained at baseline, after 2wk of S (group A) or B (group B), and at 6wks (2 wk into S+B combination therapy). Tissue was used for: lysate array (TLA) proteomic analysis of signaling proteins, IHC for CD31, VEGF, and Ki67, Raf/Ras mutation, and SNP analysis. Results: 18 sets of 3 biopsies were obtained, assessed for morphologic response (MR; decrease to <60% viable tumor seen), and processed for TLA and IHC. 11 pts had morphologic response including all 4 PR and 6/12 SD pts. Greater reduction in change in phospho(p)-ERK was seen at 2wk in group A pts (starting with sorafenib only) (p = 0.003). 9/11 MR pts had inhibition of ERK or AKT activation (p < 0.03). OvCa pts were more likely to have reduction in bRaf (p = 0.02). Pts in group B (starting with bevacizumab only) had lower microvessel density as measured by CD31 IHC (p = 0.05) at 2 wks; there was also a trend to lower VEGF expression by IHC in that group.These effects were muted at time 3, after combination treatment. No relationships to clinical outcomes were found, every pt had at least 1SNP in >1 tested gene; there were no Ras mutations and 1 V600KRaf mutation . Conclusions: These exploratory results demonstrate proof of mechanism in the tumor and its microenvironment for the combination of S and B. Randomization of initial exposure for the first 4 wks allowed interrogation of the role of the independent agents; the Raf/ERK axis was inhibited by S treatment first and there was reduction in tissue angiogenesis markers with B first. The molecularly targeted combination of sorafenib and bevacizumab is biologically active and on target. Phase II studies in multiple tumor types are ongoing.

No significant financial relationships to disclose.

Ventricular dilation and elevated aqueductal pulsations in a new experimental model of communicating hydrocephalus

In communicating hydrocephalus (CH), explanations for the symptoms and clear-cut effective treatments remain elusive. Pulsatile flow through the cerebral aqueduct is often significantly elevated, but a clear link between abnormal pulsations and ventriculomegaly has yet to be identified. We sought to demonstrate measurement of pulsatile aqueductal flow of CSF in the rat, and to characterize the temporal changes in CSF pulsations in a new model of CH. Hydrocephalus was induced by injection of kaolin into the basal cisterns of adult rats (n = 18). Ventricular volume and aqueductal pulsations were measured on a 9.4 T MRI over a one month period. Half of the animals developed ventricular dilation, with increased ventricular volume and pulsations as early as one day post-induction, and marked chronic elevations compared to intact controls (volume: 130.15 +/- 83.21 microl vs. 15.52 +/- 2.00 microl; pulsations: 114.51 nl +/- 106.29 vs. 0.72 +/- 0.13 nl). Similar to the clinical presentation, the relationship between ventricular size and pulsations was quite variable. However, the pulsation time-course revealed two distinct sub-types of hydrocephalic animals: those with markedly elevated pulsations which persisted over time, and those with mildly elevated pulsations which returned to near normal levels after one week. These groups were associated with severe and mild ventriculomegaly respectively. Thus, aqueductal flow can be measured in the rat using high-field MRI and basal cistern-induced CH is associated with an immediate change in CSF pulsatility. At the same time, our results highlight the complex nature of aqueductal pulsation and its relationship to ventricular dilation.

Complete genome sequence of Nariva virus, a rodent paramyxovirus

Nariva virus (NarPV) was isolated from forest rodents (Zygodontomys b. brevicauda) in eastern Trinidad in the early 1960s. Initial classification within the family Paramyxoviridae was based mainly on morphological observations including the structure of nucleocapsids and virion surface projections. Here, we report the characterization of the complete genome sequence of NarPV. The genome is 15,276 nucleotides in length, conforming to the rule-of-six, and has a genome organization typical of most members of the family, with six transcriptional units in the order 3′-N–P-M-F–H-L-5′. The gene junctions contain highly conserved gene start and stop signals and a tri-nucleotide intergenic sequence present in most members of the subfamily Paramyxovirinae. Sequence comparison studies indicate that NarPV is most closely related to Mossman virus, which was isolated from wild rats (Rattus leucopus) in Queensland, Australia, in 1970. This study confirmed the classification of NarPV as a member of the subfamily Paramyxovirinae and established the close genome organization and sequence relationship between the two rodent paramyxoviruses isolated almost a decade apart and from two locations separated by more than 15,000 km.

Linkage mapping of five genes on SSC12 in a Berkshire × Yorkshire cross (Brief report)

Abstract. three-generation family of pig was generated by an intercross between animals of two Berkshire grand sires and nine Yorkshire grand dams (BY), and a total of 525 F2 offspring were produced. The initial genome scan analysis identified suggestive quantitative trait loci (QTL) for fat traits on chromosome 12 (SSC12) (MALEK et al., 2001). Animals that were homozygous for Berkshire alleles had relatively less back fat than those with Yorkshire alleles, and heterozygotes were fattest for these QTL. The objective of this study was to further characterize these SSC12 QTL by mapping five additional genes (PSME3, GRB7, MAC30, RPS6KB1 and TAX1BP3) in the BY family and see if they were associated with fatness traits.