Global microsatellite content distinguishes humans, primates, animals, and plants

Microsatellites are highly mutable, repetitive sequences commonly used as genetic markers, but they have never been studied en masse. Using a custom microarray to measure hybridization intensities of every possible repetitive nucleotide motif from 1-mers to 6-mers, we examined 25 genomes. Here, we show that global microsatellite content varies predictably by species, as measured by array hybridization signal intensities, correlating with established taxonomic relationships, and particular motifs are characteristic of one species versus another. For instance, hominid-specific microsatellite motifs were identified despite alignment of the human reference, Celera, and Venter genomic sequences indicating substantial variation (30-50%) among individuals. Differential microsatellite motifs were mainly associated with genes involved in developmental processes, whereas those found in intergenic regions exhibited no discernible pattern. This is the first description of a method for evaluating microsatellite content to classify individual genomes.

Prospective study of predictors of vitamin D status and survival in patients with colorectal cancer

BACKGROUND

In an earlier study, a 25-hydroxyvitamin D(3) (25(OH)D) score calculated from known predictors of vitamin D status significantly predicted plasma levels of 25(OH)D and the risk of colorectal cancer, but the influence of the 25(OH)D score on survival after diagnosis is unknown.

MATERIALS AND METHODS

We prospectively examined the influence of post-diagnosis predicted 25(OH)D levels on mortality among 1017 participants in the Nurses' Health Study and Health Professionals Follow-Up Study who were diagnosed with colorectal cancer from 1986 to 2004. Colorectal cancer-specific and overall mortality according to quintiles of predicted 25(OH)D levels were assessed. Cox proportional hazards models were used to calculate hazard ratios (HRs) adjusted for other risk factors of survival.

RESULTS

Higher predicted 25(OH)D levels were associated with a significant reduction in colorectal cancer-specific (P trend=0.02) and overall mortality (P trend=0.002). Compared with levels in the lowest quintile, participants with predicted 25(OH)D levels in the highest quintile had an adjusted HR of 0.50 (95% CI, 0.26-0.95) for cancer-specific mortality and 0.62 (95% CI, 0.42-0.93) for overall mortality.

CONCLUSION

Higher predicted 25(OH)D levels after a diagnosis of colorectal cancer may be associated with improved survival. Further study of the vitamin D pathway in colorectal cancer is warranted.

Haptic Processing of Facial Expressions of Emotion in 2D Raised-Line Drawings

Participants haptically (vs. visually) classified universal facial expressions of emotion (FEEs) depicted in simple 2D raised-line displays. Experiments 1 and 2 established that haptic classification was well above chance; face-inversion effects further indicated that the upright orientation was privileged. Experiment 2 added a third condition in which the normal configuration of the upright features was spatially scrambled. Results confirmed that configural processing played a critical role, since upright FEEs were classified more accurately and confidently than either scrambled or inverted FEEs, which did not differ. Because accuracy in both scrambled and inverted conditions was above chance, feature processing also played a role, as confirmed by commonalities across confusions for upright, inverted, and scrambled faces. Experiment 3 required participants to visually and haptically assign emotional valence (positive/negative) and magnitude to upright and inverted 2-D FEE displays. While emotional magnitude could be assigned using either modality, haptic presentation led to more variable valence judgments. We also documented a new face-inversion effect for emotional valence visually, but not haptically. These results suggest emotions can be interpreted from 2-D displays presented haptically as well as visually; however, emotional impact is judged more reliably by vision than by touch. Potential applications of this work are also considered.

Percutaneous radiofrequency ablation of lung tumours: Results in first 100 consecutive patients

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Background: Treatment modalities for patients with primary and secondary lung malignancies who are not surgical candidates are limited. Radiofrequency ablation is a minimally invasive, lung sparing therapeutic alternative that may provide local disease control for these patients. The study reported our experience with first 100 consecutive patients who underwent radiofrequency ablation of their lung tumours. Methods: From November 2000 to December 2006, the clinical and treatment-related information regarding the 100 consecutive patients (58 males, mean age of 65 years) with 240 lung tumours treated by radiofrequency ablation were collected prospectively. Radiofrequency ablation was performed percutaneously under CT guidance with local anaethesiologic assistance and conscious sedation using a RITA Starbust XL electrode. The patients were hospitalized overnight and followed at one week, one month and then every three months with CT to evaluate treatment outcome and complications. Results: Five patients had primary lung carcinoma while the remaining patients had pulmonary metastases from extra-thoracic malignancies, with colorectal cancer being the most common primary site (68%), followed by renal cell carcinoma (8%) and uterine leiomyosarcoma (5%). The mean number of pulmonary lesions ablated was 2.4 per patient; the mean size of lesion ablated was 2.2 cm in diameter. Fifteen patients had second-time RFA; 4 patients underwent third- or fourth-time RFA for pulmonary recurrence. There was no post-procedural mortality and the overall morbidity rate was 42%. The most common complication was pneumothorax, which occurred in of 31% of procedures (n=39/127) with 20 (16%) requiring chest tube placement. After a median follow-up of 24 months (range 1 to 70 months), 72% of RFA treated lesions did not progress. The overall median disease-free interval was 13 months, with 1-, 3- and 5- year disease-free survival of 55%, 22% and 7% respectively. The overall median survival was 34 months with 1-, 3- and 5-year- survival of 85%, 49% and 33% respectively. Conclusions: Percutaneous radiofrequency ablation is an emerging therapy with promising results when surgical resection of pulmonary malignancy cannot be performed.

No significant financial relationships to disclose.

L-454,560, a potent and selective PDE4 inhibitor with in vivo efficacy in animal models of asthma and cognition

Type 4 phosphodiesterases (PDE4) inhibitors are emerging therapeutics in the treatment of a number of chronic disorders including asthma, chronic obstructive pulmonary disease (COPD) and cognitive disorders. This study delineates the preclinical profile of L-454,560, which is a potent, competitive and preferential inhibitor of PDE4A, 4B, and 4D with IC50 values of 1.6, 0.5 and 1.2 nM, respectively. In contrast to the exclusive binding of cilomilast and the preferential binding of roflumilast to the PDE4 holoenzyme state (Mg2+-bound form), L-454,560 binds to both the apo-(Mg2+-free) and holoenzyme states of PDE4. The intrinsic enzyme potency for PDE4 inhibition by L-454,560 also results in an effective blockade of LPS-induced TNFalpha formation in whole blood (IC50 = 161 nM) and is comparable to the human whole blood potency of roflumilast. The cytokine profile of inhibition of L-454,560 is mainly a Th1 profile with significant inhibition of IFNgamma and no detectable inhibition of IL-13 formation up to 1 microM. L-454,560 was also found to be efficacious in two models of airway hyper-reactivity, the ovalbumin (OVA) sensitized and challenged guinea pig and the ascaris sensitized sheep model. Furthermore, L-454560 was also effective in improving performance in the delayed matching to position (DMTP) version of the Morris watermaze, at a dose removed from that associated with potential emesis. Therefore, L-454,560 is a novel PDE4 inhibitor with an overall in vivo efficacy profile at least comparable to roflumilast and clearly superior to cilomilast.

Coenzyme Q10 in the treatment of hypertension: a meta-analysis of the clinical trials

Our objective was to review all published trials of coenzyme Q10 for hypertension, assess overall efficacy and consistency of therapeutic action and side effect incidence. Meta-analysis was performed in 12 clinical trials (362 patients) comprising three randomized controlled trials, one crossover study and eight open label studies. In the randomized controlled trials (n=120), systolic blood pressure in the treatment group was 167.7 (95% confidence interval, CI: 163.7-171.1) mm Hg before, and 151.1 (147.1-155.1) mm Hg after treatment, a decrease of 16.6 (12.6-20.6, P<0.001) mm Hg, with no significant change in the placebo group. Diastolic blood pressure in the treatment group was 103 (101-105) mm Hg before, and 94.8 (92.8-96.8) mm Hg after treatment, a decrease of 8.2 (6.2-10.2, P<0.001) mm Hg, with no significant change in the placebo group. In the crossover study (n=18), systolic blood pressure decreased by 11 mm Hg and diastolic blood pressure by 8 mm Hg (P<0.001) with no significant change with placebo. In the open label studies (n=214), mean systolic blood pressure was 162 (158.4-165.7) mm Hg before, and 148.6 (145-152.2) mm Hg after treatment, a decrease of 13.5 (9.8-17.1, P<0.001) mm Hg. Mean diastolic blood pressure was 97.1 (95.2-99.1) mm Hg before, and 86.8 (84.9-88.8) mm Hg after treatment, a decrease of 10.3 (8.4-12.3, P<0.001) mm Hg. We conclude that coenzyme Q10 has the potential in hypertensive patients to lower systolic blood pressure by up to 17 mm Hg and diastolic blood pressure by up to 10 mm Hg without significant side effects.

231 HISTOCOMPATIBLE PARTHENOGENETIC EMBRYONIC STEM CELLS

Organ or tissue transplantation is the preferred treatment for numerous diseases but is hindered by immunologic barriers. Genetically matched pluripotent embryonic stem cells generated via nuclear transfer (ntES cells) or parthenogenesis (pES cells) are possible sources of histocompatible cells and tissues. We have developed two ways of isolating pES cells that carry the full complement of major histocompatibility complex (MHC) antigens of the oocyte donors. One method entails activation of oocytes after blockade of karyokinesis in meiosis II, followed by selection of predominantly homozygous pES cells that have undergone recombination in their MHC antigen region to restore the heterozygous maternal MHC genotype (parthenote recombinant, or prES cells). The second method involves activation of immature oocytes after blockade of karyokinesis of meiosis I, followed by selection of predominantly heterozygous pES lines that retain the MHC genotype of the oocyte donor (parthenote clone recombinant, or pcrES cells). The cells are pluripotent by several criteria: teratoma formation, in vitro differentiation into hematopoietic elements, and high-level skin chimerism in blastocyst chimeras. Breeding of 8 founder females and examination of over 700 progeny failed to demonstrate germ line transmission of the pES cells. Injection of over 50 tetraploid embryos with these lines and embryo transfer have failed to support full gestational development. However, differentiated tissues from these pluripotent ES cells engraft when transplanted into genetically matched immunocompetent recipients, demonstrating that selected pES cells can serve as a source of histocompatible tissues for transplantation.

Phase I/II study of ABI-007 as first line chemotherapy in advanced non-small cell lung cancer (NSCLC)

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Background: ABI-007 is a 130-nm albumin-bound form of paclitaxel. This study was designed to determine (1) the MTD and DLTs of ABI-007 in patients with stage IV chemotherapy-naive NSCLC and (2) the efficacy and safety of ABI-007 at the MTD. Methods: Eligibility requirement included ECOG PS 0–1, adequate organ function and sensory neuropathy ≤ grade 1. No prior chemotherapy for metastatic disease was allowed. Prior EGFR TKI therapy was allowed. ABI-007 was administered on days 1, 8, and 15 every 28 days (IV over 30 min. without premedication). In the phase I portion, 3 dose levels were studied (100, 125 and 150 mg/m2) and in the phase 2 portion, 40 patients were treated at the MTD. Results: 50 patients received ABI-007; the median age was 70 yo and 76% of patients were ≥ 65 yo. No DLTs were observed at the 100 and 125 mg/m2 dose level. However at the 150 mg/m2 dose level 2/6 patients had a DLT (febrile neutropenia and sensory neuropathy, respectively) during cycle 1 such that the MTD was exceeded. The 125 mg/m2 dose level was identified as the MTD and expanded to 40 patients in the phase 2 portion of this study. Toxicity and efficacy data is presented for the phase 2 portion. Ten patients (25%) had received prior neoadjuvant or adjuvant chemotherapy and 5 (13%) had received prior gefitinib or erlotinib. Sensory neuropathy was the most frequent toxicity with grade 2 and 3 toxicity occurring in 8% and 15% of patients. Grade 2 and 3 fatigue was observed in 8% and 13% of patients. Grade 3 and 4 neutropenia occurred in 10% and 3% of patients with no febrile neutropenia observed. Response was assessed by RECIST. One CR and 14 PRs were observed for an overall response rate of 15/40 (38%). The median survival was 10.3 months. Conclusions: The MTD for ABI-007 administered over 30 min. on days 1, 8, and 15 every 28 days was 125 mg/m2. No hypersensitivity reactions were observed and no premedication was given. In the phase 2 portion, a 38% response rate and 10.3 month survival was observed. Non-hematologic toxicities were primarily sensory neuropathy and fatigue. Myelosuppression was minimal and no febrile neutropenia was observed. Further development of ABI-007 in NSCLC is warranted based on the encouraging single agent activity observed in this study.

[Table: see text]

SUV in pelvic lymph node is a significant prognostic factor in previously untreated squamous carcinoma of the uterine cervix

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Background: The aim of this prospective study was to identify prognostic factors (including 18F-fluorodeoxyglucose positron emission tomography [FDG-PET] parameters) in previously untreated squamous carcinoma of the uterine cervix with MRI- or CT-defined pelvic or para-aortic lymph node (PLN or PALN) metastasis. Methods: This study included pooled patients selected from two prospective studies who had untreated squamous cell cervical cancer and PLN or PALN metastasis (diagnostic score 3 or 4) by CT-MRI and additional FDG-PET scans were performed for primary staging. Recurrence-free and overall survivals (RFS and OS) were evaluated using the Kaplan-Meier method. Prognostic variables were assessed by the log-rank test and Cox proportional hazards regression method. Optimal cut-offs of standardized uptake value (SUV) in primary tumor, PLN and PALN were determined by receiver operating characteristic and area under the curve analysis. Results: A total of 70 patients were eligible for analysis. The follow-up time ranged 16–59 months (mean ± SD: 38 ± 18). In univariate analyses, FIGO stage ≥ III, PET defined bilateral PLN-positive, PET defined PLN-positive, PET defined PALN-positive and SUV cut-off of 3.04 at PLN and 4.18 at PALN were significant for RFS. FIGO stage ≥ III, SUV cut-offs of 2.94–3.15 at PLN and SUV cut-offs of 2.61–4.91 at PALN were significant for OS. Multivariate analysis showed only SUVmax cut-off of 3.04 at PLN was a significant adverse factors for RFS (RR: 10.1 95% CI 2.2–46.0; P = 0.003) and OS (RR: 11.7 95% CI 1.5–92.6; P = 0.019), while SUVmax cut-off of 4.18 at PALN (P = 0.062) was marginally significant for OS. Conclusions: SUVmax cut-off of 3.04 at PLN was a significant adverse factor for RFS and OS in previously untreated squamous carcinoma of the uterine cervix with MRI- or CT-defined PLN or PALN metastasis.

No significant financial relationships to disclose.

The effects of body weight on airway calibre

Increased wheeze and asthma diagnosis in obesity may be due to reduced lung volume with subsequent airway narrowing. Asthma (wheeze and airway hyperresponsiveness), functional residual capacity (FRC) and airway conductance (Gaw) were measured in 276 randomly selected subjects aged 28-30 yrs. Data were initially adjusted for smoking and asthma before examining relationships between weight and FRC (after adjustment for height), and between body mass index (BMI = weight.height(-2)) and Gaw (after adjustment for FRC) by multiple linear regression, separately for females and males. For males and females, BMI (+/-95% confidence interval) was 27.0+/-4.6 kg.m(-2) and 25.6+/-6.0 kg.m(-2) respectively, Gaw was 0.64+/-0.04 L.s(-1).cmH2O(-1) and 0.57+/-0.03 L.s(-1).cmH2O(-1), and FRC was 85.3+/-3.4 and 84.0+/-2.9% of predicted. Weight correlated independently with FRC in males and females. BMI correlated independently and inversely with Gaw in males, but only weakly in females. In conclusion, obesity is associated with reduced lung volume, which is linked with airway narrowing. However, in males, airway narrowing is greater than that due to reduced lung volume alone. The mechanisms causing airway narrowing and sex differences in obesity are unknown.