iFLAS: positive-unlabeled learning facilitates full-length transcriptome-based identification and functional exploration of alternatively spliced isoforms in maize

The advent of full-length transcriptome sequencing technologies has accelerated the discovery of novel splicing isoforms. However, existing alternative splicing (AS) tools are either tailored for short-read RNA-Seq data or designed for human and animal studies. The disparities in AS patterns between plants and animals still pose a challenge to the reliable identification and functional exploration of novel isoforms in plants. Here, we developed integrated full-length alternative splicing analysis (iFLAS), a plant-optimized AS toolkit that introduced a semi-supervised machine learning method known as positive-unlabeled (PU) learning to accurately identify novel isoforms. iFLAS also enables the investigation of AS functions from various perspectives, such as differential AS, poly(A) tail length, and allele-specific AS (ASAS) analyses. By applying iFLAS to three full-length transcriptome sequencing datasets, we systematically identified and functionally characterized maize (Zea mays) AS patterns. We found intron retention not only introduces premature termination codons, resulting in lower expression levels of isoforms, but may also regulate the length of 3'UTR and poly(A) tail, thereby affecting the functional differentiation of isoforms. Moreover, we observed distinct ASAS patterns in two genes within heterosis offspring, highlighting their potential value in breeding. These results underscore the broad applicability of iFLAS in plant full-length transcriptome-based AS research.

Impact of Differential Rates of Disease Progression in Amyloid-Positive Early Alzheimer's Disease: Findings from a Longitudinal Cohort Analysis

BACKGROUND

There is limited literature regarding the impact of differential rates of disease progression on longitudinal outcomes in individuals with early Alzheimer's disease (AD) and confirmed brain amyloid pathology.

OBJECTIVES

To describe the underlying characteristics and long-term outcomes associated with different rates of disease progression among amyloid-positive individuals with early symptomatic AD.

DESIGN

Retrospective observational study.

SETTING

Data from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS) in the United States (06/2005-11/2021).

PARTICIPANTS

Individuals with a clinical assessment of mild cognitive impairment or dementia and Clinical Dementia Rating® Dementia Staging Instrument Sum of Boxes (CDR-SB) score 0.5-9.0 (inclusive; first visit defined as the index date) and confirmed amyloid positivity. Participants were stratified into No Progression (change ≤0), Slower Progression (0< change <2.0 points), Median Progression (2.0-point change), and Faster Progression (change >2.0 points) cohorts based on the observed distribution of changes in CDR-SB score between the index and first subsequent visit.

MEASUREMENTS

For each cohort, the functional and neuropsychiatric outcomes were described at index and each subsequent visit for up to five years, and least-square (LS) mean changes from baseline were estimated using linear mixed-effects models adjusting for baseline demographic and clinical characteristics.

RESULTS

Among 1,263 participants included in the analysis, the mean±standard deviation (SD) age at index was 72.7±9.7 years and 55.3% were males. Demographic characteristics and comorbidity profiles at index were similar across cohorts. However, at index, the Faster Progression (N=279) cohort had higher CDR-SB and Functional Assessment Questionnaire (FAQ) scores compared with the No Progression (N=474), Slower Progression (N=297), and Median Progression (N=213) cohorts. Adjusting for baseline characteristics, at year 5 after index the FAQ score increased by 23.6 points for Faster Progression cohort and 10.4, 15.8, and 19.2 points for the No, Slower, and Median Progression cohorts, respectively. The corresponding increases in Neuropsychiatric Inventory Questionnaire (NPI-Q) scores were 6.7 points for the Faster Progression cohort, and by 1.3, 3.1, and 8.3 points, for the No, Slower, and Median Progression cohorts, respectively.

CONCLUSIONS

Despite similar demographic and clinical profiles at baseline, amyloid-positive individuals with greater deterioration based on CDR-SB early in the AD trajectory continue to experience worse functional and behavioral outcomes over time than those with more gradual deterioration in this metric.

Potential Implications of Slowing Disease Progression in Amyloid-Positive Early Alzheimer's Disease: Estimates from Real-World Data

BACKGROUND

Emerging therapies have shown promising results for slowing the progression of Alzheimer's disease (AD). However, the potential impact of these therapies on real-world outcomes remains to be explored.

OBJECTIVE

To examine the impact of slowing AD progression on functional abilities and behavioral symptoms.

DESIGN

Retrospective observational study.

SETTING

Data from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS) in the United States (06/2005-11/2021, primary analysis) and the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (09/2005-03/2022, sensitivity analysis) were used.

PARTICIPANTS

Individuals with mild cognitive impairment (MCI) or mild dementia, Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) score 0.5-9.0 (inclusive; first visit defined as the index date), and confirmed amyloid positivity were identified in NACC. In ADNI, individuals with at least one clinical center visit with a clinical assessment of MCI or mild dementia and confirmed amyloid positivity were identified.

MEASUREMENTS

Hypothetical effects of slowing disease progression as assessed by CDR-SB on functional and behavioral outcomes including the Functional Activities Questionnaire (FAQ) score, Neuropsychiatric Inventory Questionnaire (NPI-Q) score, and the probability of complete dependence over five years were evaluated using multivariable regression among NACC participants, separately for the subgroups with MCI and mild dementia at baseline, respectively. For the ADNI sensitivity analysis, the hypothetical effects of slowing disease progression were evaluated for FAQ score using multivariable regression among the MCI participants only.

RESULTS

Compared with natural disease progression, slowing progression by 20% over five years for NACC participants with MCI and mild dementia, respectively, would result in 1.7-point (10.8%) and 1.6-point (12.9%) less deterioration based on FAQ; 0.5-point (20.3%) and 0.5-point (19.3%) less deterioration based on NPI-Q; 4.7 percentage-point (22.2%) and 10.1 percentage-point (21.6%) lower probability of complete dependence. Among ADNI participants, delaying disease progression by 20% or 30% over 4 years would avert deterioration based on FAQ of 1.1 points (20.4%) and 1.6 points (29.6%), respectively, compared to natural disease progression.

CONCLUSIONS

Slowing early AD progression could result in preservation of functional and behavioral attributes and functional autonomy for longer.

Causal relationship between Type 1 diabetes and osteoporosis and fracture occurrence: a two-sample Mendelian randomization analysis

We used two-sample Mendelian Randomization to reveal causal estimates of type 1 diabetes and bone. Type 1 diabetes was found to be a risk factor for bone metabolic health, although there was no clear evidence to support a genetic association between type 1 diabetes and osteoporosis and fracture risk.

INTRODUCTION

Based on the random assignment of gametes at conception, Mendelian randomization (MR) analysis simulates randomized controlled trials in an observational setting. Therefore, we used MR to assess the association causality of type 1 diabetes (T1D) with fractures and osteoporosis.

METHODS

From a genome-wide association meta-analysis, independent single nucleotide polymorphisms closely associated with T1D were selected as instrumental variables. Data on fracture and osteoporosis were obtained from the FinnGen Consortium. We performed a two-sample MR analysis, using inverse-variance weighted (IVW) as the primary analysis method, to assess possible causal associations between T1D and bone risk. The results were verified by MR-Egger regression and median weighted method (WME). MR-PRESSO and MR-Egger intercepts were used to evaluate the horizontal pleiotropy of instrumental variables, and the Q-test and "leave-one-out" methods were used to test the heterogeneity of MR results.

RESULTS

IVW (OR=1.040, 95% CI=0.974-1.109, P=0.238), MR-Egger regression (OR=1.077, 95% CI=0.921-1.260, P=0.372) and WME (OR=1.021, 95% CI=0.935-1.114, P=0.643) all showed that there was no causal relationship between T1D and osteoporosis, but the direction was consistent. The indicative significance of IVW results in T1D and forearm fractures (OR=1.062, 95% CI=1.010-1.117, P=0.020), but the results are not robust enough. There was no causal effect in femur, lumbar and pelvis, or shoulder and upper arm fractures.

CONCLUSIONS

After MR analysis, although T1D may be a risk factor for bone health, we do not have sufficient evidence to support a causal effect of T1D on osteoporosis and fractures at a genetically predicted level. More cases need to be included for analysis.

Hysteroscopic myomectomy with the IBS® Intrauterine Bigatti Shaver: A Retrospective Comparative Analysis of the impact of rotational speed and aspiration flow rate

Background: Myoma removal remains a challenge hysteroscopically including for the “IBS®” Intrauterine Bigatti Shaver technique. Objective: To evaluate whether the Intrauterine IBS® instrument settings and the myoma size and type are prognostic factors for the complete removal of submucous myomas using this technology. Materials and methods: This study was conducted at the San Giuseppe University Teaching Hospital Milan, Italy; Ospedale Centrale di Bolzano - Azienda Ospedaliera del Sud Tirolo Bolzano, Italy (Group A) and the Sino European Life Expert Centre-Shanghai Jiao Tong University School of Medicine Affiliated Renji Hospital, Shanghai, China (Group B). In Group A: surgeries were performed between June 2009 and January 2018 on 107 women using an IBS device set to a rotational speed of 2,500 rpm and an aspiration flow rate of 250ml/min. In Group B: surgeries were performed between July 2019 and March 2021 on 84 women with the instrument setting to a rotational speed of 1,500 rpm and aspiration flow rate of 500 ml/min. Further subgroup analysis was performed based on fibroid size:<3 cm and 3-5 cm. Both Groups A and B were similar in terms of patient age, parity, symptoms, myoma type and size. Submucous myomas were classified according to the European Society for Gynaecological Endoscopy classification. All patients underwent a myomectomy with the IBS® under general anaesthesia. The conventional 22 Fr. Bipolar Resectoscope was used in cases requiring conversion to the resection technique. All surgeries were planned, performed and followed by the same surgeon in both institutions. Main outcome measures: Complete resection rates, total operation time, resection time and used fluid volume. Results: Complete resection with the IBS® Shaver was seen in 93/107 (86.91%) in Group A versus 83/84 (98.8 %) in Group B (P=0.0021). Five patients (5.8%) in Subgroup A1 (<3 cm) and nine patients (42.9%) in Subgroup A2 (3cm~5cm) could not be finished with the IBS (P<0.001, RR=2.439), while in Group B only one case (8.3%) in Subgroup B2 (3cm~5cm) underwent a conversion to bipolar resectoscope (Group A: 14/107=13.08% vs. Group B: 1/84=1.19%, P=0.0024). For <3cm myomas (subgroup A1 versus B1) there was a statistically significant difference in terms of resection time (7.75±6.363 vs. 17.28±12.19, P<0.001), operation time (17.81 ± 8.18 vs. 28.19 ±17.614, P<0.001) and total amount of fluid used (3365.63 ± 2212.319 ml vs. 5800.00 ± 8422.878 ml, P<0.05) in favour of Subgroup B1. For larger myomas, a statistical difference was only observed for the total operative time (51.00±14.298 min vs. 30.50±12.122 min, P=0.003). Conclusion: For hysteroscopic myomectomy using the IBS®, 1,500rpm rotational speed and 500ml/min aspiration flow rate are recommended as these settings result in more complete resections compared to the conventional settings. In addition, these settings are associated with a reduction in total operating time. What is new? Reducing the rotational speed rate from 2500 rpm to 1500 rpm and increasing the aspiration flow rate from 250 ml/min to 500 ml/min improve complete resection rates and reduce operating times.

Safety and tolerance of Lacticaseibacillus paracasei N1115 in caesarean-born young children: a randomised, placebo-controlled trial

The administration of probiotics may help to improve dysbiosis and related health problems in children delivered by caesarean section. However, the effects are strain specific, and safety combined tolerance are considered a priority. The aim of this study was to evaluate the safety and tolerance of Lacticaseibacillus paracasei N1115 in caesarean-born children aged 6-24 months via a randomised, placebo-controlled intervention study. In total, 101 children were included and randomised to receive either a sachet of L. paracasei N1115 (2×1010 cfu/g, 2 g/day) or placebo (maltodextrin, 2 g/day) per day for 12 weeks. Anthropometric parameters were measured by trained nurses, and defecation characteristics, gastrointestinal symptoms, (serious) adverse events ((s)AEs), crying patterns and lifestyle behaviours were recorded by parents or guardians. Neurocognitive development was assessed by the Ages and Stages Questionnaires-3 (ASQ-3) before and after the intervention. The only difference between groups regarding defecation characteristics was a significant treatment × time effect on stool frequency (P=0.007), as the number of defecations was significantly higher in the probiotic group (around 1.2-1.3 times/day) than in the placebo group (around 1.0 times/day) in the later intervention period (P=0.035 at week 9; P=0.048 at week 10; P=0.026 at week 12). The use of L. paracasei N1115 also reduced the incidence rate of constipation (Incidence rate ratio (IRR): 0.120; 95% confidence interval (CI): 0.015, 0.967; P=0.046) and abdominal pain (IRR: 0.562; 95% CI: 0.358, 0.882; P=0.012). Changes in anthropometric parameters, including weight, height and head circumference, did not differ significantly between groups, nor did measures of crying, sleep, outdoor activity, temper, appetite or the ASQ-3 scores. No adverse events associated with consumption of the probiotic were reported. Thus, the administration of L. paracasei N1115 is safe and well-tolerated in caesarean-born children aged 6-24 months. Furthermore, it may ameliorate gastrointestinal function to some extent.

Intrauterine Bigatti Shaver (IBS ® ) successful placental remnants removal, after caesarean section for a cervical pregnancy with placenta accreta

Placenta accreta located in a caesarean section scar is difficult to remove. The Intrauterine Bigatti Shaver (IBS®) has already been proven to be effective in placental remnant removal. Our case report highlights that the IBS® is also a safe method to remove placental remnants attached to a previous caesarean section scar performed for a cervical pregnancy and associated with placenta accreta.

Role of local treatment in primary breast B-cell non-Hodgkin's lymphoma: a propensity score matching-based analysis from SEER database

OBJECTIVE

Primary breast lymphoma (PBL) has been defined as disease localized to breast with or without ipsilateral axillary nodal involvement. Primary breast B-cell non-Hodgkin's lymphoma is rare to be diagnosed clinically. The role of surgery and radiotherapy (RT) as local treatment is unclear. The aim of this study was to evaluate the prognostic factors and investigate the effect of local treatment in patients with primary breast B-cell non-Hodgkin's lymphoma.

MATERIALS AND METHODS

We identified patients with primary breast B-cell non-Hodgkin's lymphoma diagnosed between 1998 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed to reduce possible bias between groups. The overall survival (OS) and disease-specific survival (DSS) were calculated using the Kaplan-Meier method. Multivariate Cox regression analysis was used to identify independent prognostic factors.

RESULTS

Altogether 956 patients with primary breast B-cell non-Hodgkin's lymphoma were included. Most patients were white women over the age of 60. The most common histological type was diffuse large B cell lymphoma (DLBCL), and most patients present with stage I disease. Furthermore, old age (>60 years), DLBCL histology and stage IIE disease were the statistically significant factors associated with worse OS and DSS. Surgery did not improve survival of patients, and surgery combined with RT did not achieve a better prognosis than RT alone. RT was associated with better survival in patients with stage IE DLBCL, but patients with stage IE MZL and FL and stage IIE primary breast B-cell non-Hodgkin's lymphoma could not benefit from RT.

CONCLUSIONS

In local treatment, surgery offered no survival benefit for patients with primary breast B-cell non-Hodgkin's lymphoma, while RT is an effective choice because it can improve both OS and DSS in the stage IE DLBCL subgroup.

[Relationship between nutrients intake during pregnancy and the glycemic control effect in pregnant women with gestational diabetes mellitus]

OBJECTIVE

To explore the relationship between nutrients intake during pregnancy and the glycemic control effect in pregnant women with gestational diabetes mellitus (GDM).

METHODS

Pregnant women for 25-35 gestational weeks who underwent prenatal examination and completed GDM diagnostic test in two third-class hospitals in Beijing from October 2015 to October 2017 were recruited to participate in the cohort study, and were investigated at enrollment, 2 weeks after enrollment, and delivery. The cross-sectional survey data 2 weeks after enrollment was used for this study. Among them, dietary survey used the 24 h dietary records to collect the food intake of the subjects for the past day, and the intake of energy, macronutrients and micronutrients, was calculated according to the Chinese Food Composition Table. Using the data of fasting blood glucose (FBG) collected by clinical information system and referring to the Chinese Guidelines for the Diagnosis and Treatment of Pregnancy Diabetes (2014), the GDM patients with FBG ≤5.3 mmol/L were divided into the well-control group, those with FBG >5.3 mmol/L were divided into poorly-control group, and pregnant women with normal glucose tolerance were consi-dered as the normal group. Binary Logistic regression was used to analyze the association between the nutrients intake and glycemic control effect in pregnant women with GDM.

RESULTS

A total of 227 pregnant women were enrolled, including 104 GDM patients and 123 normal pregnancy women. Among them, 76 subjects in the well-control group (73.1%, 76/104) and 28 subjects in the poorly-control group (26.9%, 28/104). Compared with the well-control group and the normal group, the protein intake and its energy ratio of the poorly-control group were significantly higher, while carbohydrate energy ratio was significantly lower. In terms of micronutrients, there was no significant difference between the well-control group and the poorly-control group. After adjusting for age, gestational age and physical activity level, with the well-control group as the control group, binary Logistic regression model showed that higher protein energy ratio was positively correlated with poorly glycemic control effect in pregnant women with GDM (OR=6.12, 95%CI: 1.44-25.98), while higher carbohydrate energy ratio was negatively correlated with poorly glycemic control (OR=0.54, 95%CI: 0.32-0.91).

CONCLUSION

Reduced protein intake and increased carbohydrate intake were associated with better glycemic control in pregnant women with GDM. It is suggested that GDM patients should adjust their dietary pattern further to achieve good glycemic control effect.

Recurrent Extra-gastrointestinal Stromal Tumor of the Vagina: A Case Report and Review of the Literature

Gastrointestinal tumors are uncommonly found outside the gastrointestinal tract, and extremely rare in the vaginal wall. In this case report, a 39-year-old female, she was finally diagnosed with an extra gastrointestinal stromal tumor (EGIST) when she presented with a recurrent vaginal tumor, while misdiagnosed after the first surgery. She had definitive surgical clearance and was taking targeted drug therapy with no sign of recurrence after follow-up for 13 months. Immunohistochemistry and cytogenetic's remain the most definitive method to diagnose EGISTs. Surgical resection and postoperative adjuvant targeted therapy are the optimum treatment options.

Catheter ablation in adults with congenital heart disease: a 15-year perspective from a tertiary center

Background

With the growing population of adults with congenital heart disease (ACHD), the number of catheter ablation procedures is expected to increase over time.

Purpose

We aimed to describe temporal trends in volume and outcomes of catheter ablation procedures in ACHD patients in a large tertiary center.

Methods

Retrospective observational study including all consecutive ACHD patients undergoing catheter ablation in a tertiary reference center over a 15-year period. Acute procedural success rate (including complete success in case of non-inducibility of any arrhythmia at the end of the procedure) as well as freedom from recurrence at 12 months were analyzed.

Results

From November 2004 to November 2019, 302 catheter ablations in 221 ACHD patients (43.6±15.0 years, 58.9% males) were performed. The annual number of catheter ablation increased progressively from 4 to 60 by year (p&lt;0.001). Intra-atrial reentrant tachycardia/focal atrial tachycardia was the most common targeted arrhythmia (n=217, 71.9%). Over the study period, acute procedural success rate increased from 45.0% to 93.3% (p&lt;0.001), including complete acute procedural success from 45.0% to 88.1% (p&lt;0.001) (Figure 1). The use of irrigated catheters (30.0% to 94.8%, p&lt;0.001), 3D-mapping systems (60.0% to 96.3%, p&lt;0.001), contact force catheters (0.0% to 91.9%, &lt;0.001), and high-density mapping (0.0% to 71.9%, p&lt;0.01) increased significantly. Use of irrigated catheters (OR=3.96, 95% CI: 1.79–8.55), 3D-mapping system (OR=3.55, 95% CI: 1.62–7.55), contact force catheters (OR=3.46, 95% CI: 1.71–7.25), and high-density mapping (OR=3.85, 95% CI: 1.60–7.26) were associated with acute procedural success. The rate of freedom from any recurrence at 12 months increased from 29.4% to 66.2% (p=0.001). Seven (2.3%) non-fatal complications occurred.

Conclusions

The number of catheter ablation procedures in ACHD patients has considerably increased over the last 15 years. Advances in ablative technologies appear to be associated with a low rate of complications and a significant improvement in acute and midterm outcomes.

Evolution of acute procedural success

Funding Acknowledgement

Type of funding source: None

Prognostic value and association of systemic inflammation for patients with stage IV gastric cancer

OBJECTIVE

The present study is aimed at investigating the prognostic value and association of systemic inflammation (neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and lymphocyte-to-monocytes ratio) for patients with stage IV gastric cancer.

METHODS

In this retrospective study, patients with stage IV gastric cancer between January 2008 and December 2017 were included. A summary was performed on clinicopathological characteristics and a multivariate cox regression analysis was performed to identify the prognostic factors.

RESULTS

304 patients with stage IV gastric cancer were included in the study. On multivariate analysis, the systemic chemotherapy (p < .001), the jaundice (p = .004), the high neutrophil-to-lym- phocyte ratio (p = .005) and the high platelet-to-lymphocyte ratio (p = .041) were independent prognostic factors for patients with stage IV gastric cancer.

CONCLUSION

As systemic inflammation response markers, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are significantly associated with OS for stage IV gastric cancer patients. Systemic chemotherapy shows a clear overall survival benefit in patients with stage IV gastric cancer and Jaundice indicates poor overall survival.

MiR-425 involves in the development and progression of renal cell carcinoma by inhibiting E2F6

OBJECTIVE

To investigate the effect of miR-425 on the proliferation and apoptosis of clear cell renal carcinoma (ccRCA) cells, and to explore the underlying mechanism.

PATIENTS AND METHODS

A total of 80 pairs of human clear cell renal carcinoma (ccRCA) and cancer-adjacent normal tissue samples were collected in this study. Human ccRCA cell line (786-O) and normal human kidney cell line (HK-2) were used in cellular research. The expression level of miR-425 was detected in ccRCA tissues and cells, respectively. Target genes of miR-425 were predicted by bioinformatics and verified by luciferase reporter gene assay. Moreover, the role of miR-425 in regulating E2F6 as well as its effect on the proliferation and apoptosis of ccRCA cells were detected.

RESULTS

Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) results showed that the expression of miR-425 was significantly decreased in ccRCA tissues and cells. The proliferation ability and cell cycle of 786-O cells were significantly inhibited after miR-425 overexpression. The percentage of cells in G0/G1 phase was remarkably increased, while the percentage of cells in S and G2/M phases was significantly decreased. Besides, the number of apoptotic cells was significantly increased in the miR-425 intervention group. On-line target gene prediction software indicated that E2F6 was the potential downstream target gene of miR-425. RT-PCR, Western blotting and luciferase reporter gene assay demonstrated that the expression of E2F6 was negatively regulated by miR-425. In addition, subsequent experiments showed that the up-regulation of E2F6 could suppress the inhibitory effect of miR-425 on the proliferation and apoptosis of ccRCA cells.

CONCLUSIONS

Our research demonstrated the inhibitory function of miR-425 in ccRCA. Therefore, the miR-425/E2F6 axis was expected to be one of the targets of ccRCA targeted therapy.

Discovery of potential biomarkers for osteoporosis using LC-MS/MS metabolomic methods

Our study focused on the associations of metabolites with BMD and osteoporosis, finding that several metabolites are associated with BMD, and metabolites combined with bone turnover markers tend to be more sensitive in distinguishing osteoporosis in both males and postmenopausal females, which might be meaningful for the early diagnosis of osteoporosis.

INTRODUCTION

Our study aimed to evaluate the association of metabolites with bone, trying to find new metabolic markers that are distinguishing for low bone mineral density (BMD).

METHODS

Our study recruited 320 participants, including 138 males and 182 postmenopausal females from the Shanghai area. Bone turnover markers (BTMs), including osteocalcin, PINP and β-CTX, and other biochemical traits were tested. BMD values of the lumber spine (L1-4), femoral neck and total hip were determined using dual-energy X-ray absorptiometry and the serum metabolome profiles including 221 metabolites from five groups (acylcarnitines, amino acids, biogenic amines, glycerophospholipids, sphingolipids and hexose) were assessed by mass spectrometry.

RESULTS

No visual separation in the metabolic profiles between different BMD groups was observed in principal component analysis (PCA) or partial least squares discriminant analysis (PLS-DA) models. We compared metabolites in three groups with different BMD levels in males and postmenopausal females separately and further filtering these metabolites via random forest-based feature selection, a commonly applied machine learning algorithm which could select the features with the greatest impact on osteoporosis, then metabolites with the highest importance (≥ 5%) (5 in males and 9 in postmenopausal females) were selected to construct better models for osteoporosis classification. After adding these selected metabolites to the model, the area under the curve (AUC) of receiver operating characteristic (ROC) curves increased significantly (BTMs: AUC 0.729, 95% CI 0.647-0.802, p < 0.0001, model 1: AUC = 0.828, 95% CI 0.754-0.888, p < 0.0001; model 1 versus model of BTMs: p = 0.0158) compared to the AUC of the BTM-only model in males. Similar results were also observed in postmenopausal females (BTMs: AUC = 0.638, 95% CI 0.562-0.708, p = 0.0025; model 2: AUC = 0.741, 95% CI 0.669-0.803, p < 0.0001; model 1 versus model of BTMs: p = 0.0182).

CONCLUSION

Metabolites combined with traditional BTMs tend to better markers for distinguishing osteoporosis in both males and postmenopausal females than BTMs alone.

Transgenic characterization of two silkworm tissue-specific promoters in the haemocyte plasmatocyte cells

Haemocytes play crucial roles in insect metabolism, metamorphosis, and innate immunity. As a model of lepidopteran insects, the silkworm is a useful model to study the functions of both haematopoiesis and haemocytes. Tissue-specific promoters are excellent tools for genetic manipulation and are widely used in fundamental biological research. Herein, two haemocyte-specific genes, Integrin β2 and Integrin β3, were confirmed. Promoter activities of Integrin β2 and Integrin β3 were evaluated by genetic manipulation. Quantitative real-time PCR and western blotting suggested that both promoters can drive enhanced green fluorescent protein (EGFP) specifically expressed in haemocytes. Further evidence clearly demonstrated that the transgenic silkworm exhibited a high level of EGFP signal in plasmatocytes, but not in other detected haemocyte types. Moreover, EGFP fluorescence signals were observed in the haematopoietic organ of both transgenic strains. Thus, two promoters that enable plasmatocytes to express genes of interest were confirmed in our study. It is expected that the results of this study will facilitate advances in our understanding of insect haematopoiesis and immunity in the silkworm, Bombyx mori.

Association of Spicy Food Consumption Frequency with Serum Lipid Profiles in Older People in China

OBJECTIVES

There has been recent interest in spicy foods and their bioactive ingredients for cardiovascular health. This study aims to explore relationship between spicy food consumption frequency and serum lipid profiles in a cross-sectional sample of older Chinese from China Health and Nutrition Survey (CHNS).

METHODS

A total of 1549 participant aged 65 years and above from CHNS 2009 were included in the analysis. Information on spicy food consumption was obtained using a questionnaire survey and 24h dietary recalls over three consecutive days combined with weighted food inventory. Fasting blood samples were analyzed for total cholesterol (TC), triglycerides, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (apoA1) and apolipoprotein B (apoB). Correlations between spicy food consumption frequency and serum lipid profiles were evaluated by multivariate linear regression models.

RESULTS

The result shows a significant positive association between frequency of spicy food consumption estimated by the frequency question and daily spicy food intake calculated from 24h recall. After adjustment for potential lifestyle and dietary confounding factors, men with higher frequency of spicy food consumption showed higher apoA1 level, and lower ratio of LDL-C/apoB (p for trend <0.05). For female, frequency of spicy food consumption was significantly associated with TC, LDL-C, apoB, LDL-C/HDL-C, and apoB/apoA1 in an inverse manner, and positively correlated with apoA1 level (p for trend <0.05).

CONCLUSION

In this study with Chinese aged 65y and above, increased spicy food consumption frequency may favorably associated with some risk factors for cardiovascular diseases.

Serum fatty acid patterns in patients with schizophrenia: a targeted metabonomics study

Previous studies have indicated that schizophrenia is linked to abnormal lipid metabolism. Free fatty acids (FFAs) in peripheral blood can reflect the status of lipid metabolism in human body. The purpose of this study was to scan the FFA pattern and elucidate the characteristics of lipid metabolic abnormality in schizophrenia patients. One hundred and ten patients with schizophrenia (SCZs) and 109 healthy controls (HCs) were included in the study and divided into a discovery set and a validation set. Forty-seven serum FFAs were detected by UPLC-QTOF-MS and 39 of them were absolutely quantified by establishing standard curves. Monounsaturated fatty acids (MUFAs) and ω-6 polyunsaturated fatty acids (ω-6 PUFAs) were significantly increased in SCZs compared with HCs. Desaturation from saturated fatty acids to MUFAs and β-oxidation were enhanced, as estimated by the ratios of products to precursors. These results suggest that lipolysis and β-oxidation are upregulated in SCZ, presumably resulting from insufficient brain energy supply.

A Case-Control Study to Determine the Prognostic Features of Salivary Epithelial Cells in Periodontitis

Periodontitis-a biofilm-induced immunoinflammatory pathology-often progresses gradually, exhibiting periodic bursts and resolution. Exfoliating oral epithelial cells act as reservoirs for key periodontal pathogens, facilitating reinfection or infection of new sites. Since saliva is a rich source of oral epithelial cells, we hypothesized that the microbial and functional profile of salivary epithelial cells (SECs) will reflect the in situ host response and disease severity. We used a case-control study design. Unstimulated whole saliva was collected from 20 chronic periodontitis patients and 20 healthy controls in accordance with the institutional review board. The isolated SECs were assessed for viability by trypan blue exclusion. Gram-stained SECs were analyzed by ImageJ, and Gram stain index (GSI) per SEC was calculated. Equal numbers of SECs from each sample were exposed to 2 periodontal pathogens- Porphyromonas gingivalis and Fusobacterium nucleatum-in biofilm or planktonic formulations at varying proportions. Cytokines in culture supernatants were assessed by ELISA (enzyme-linked immunosorbent assay). Additionally, soluble Toll-like receptor 2 (sTLR-2)-a pattern recognition receptor capable of binding microbial ligands associated with periodontitis-was measured in clarified saliva by ELISA. An increased number of SECs, a higher GSI/SEC, and a lower sTLR-2 were observed in periodontitis saliva as compared with healthy saliva. SECs from periodontitis saliva secreted higher amounts of interleukin 8 in response to P. gingivalis, and the presence of F. nucleatum dampened the response. Nonsurgical periodontal treatment improved clinical parameters, reduced the number of SECs, decreased GSI/SEC, and increased sTLR-2 in clarified saliva. In conclusion, our data suggest that SECs can provide a phenotypically distinct individualized resource for assessing epithelial response to pathogens in the course of periodontal disease. Furthermore, correlation between the sTLR-2 and GSI/SEC suggests that the expression profile of epithelial and soluble Toll-like receptor could provide an indirect measure of periodontal disease-associated dysbiosis. Knowledge Transfer Statement: The results of this study can be used for prognostic evaluation of chronic periodontitis in response to therapy and provide an opportunity for early identification of poor responders. A chip-based simple test incorporating the identified salivary epithelial cell characteristics can be developed and validated for future clinical applications, especially for monitoring patients with increased susceptibility for refractory and/or recurrent periodontitis.

First Measurement of Electron Neutrino Appearance in NOvA

We report results from the first search for ν_{μ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.99±0.11(syst) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of 1.07±0.14(syst). The 3.3σ excess of events observed in the primary analysis disfavors 0.1π<δ_{CP}<0.5π in the inverted mass hierarchy at the 90% C.L.

Renal Function in De Novo Liver Transplant Recipients Receiving Different Prolonged-Release Tacrolimus Regimens-The DIAMOND Study

DIAMOND: multicenter, 24-week, randomized trial investigating the effect of different once-daily, prolonged-release tacrolimus dosing regimens on renal function after de novo liver transplantation. Arm 1: prolonged-release tacrolimus (initial dose 0.2mg/kg/day); Arm 2: prolonged-release tacrolimus (0.15-0.175mg/kg/day) plus basiliximab; Arm 3: prolonged-release tacrolimus (0.2mg/kg/day delayed until Day 5) plus basiliximab. All patients received MMF plus a bolus of corticosteroid (no maintenance steroids).

PRIMARY ENDPOINT

eGFR (MDRD4) at Week 24. Secondary endpoints: composite efficacy failure, BCAR and AEs. Baseline characteristics were comparable. Tacrolimus trough levels were readily achieved posttransplant; initially lower in Arm 2 versus 1 with delayed initiation in Arm 3. eGFR (MDRD4) was higher in Arms 2 and 3 versus 1 (p = 0.001, p = 0.047). Kaplan-Meier estimates of composite efficacy failure-free survival were 72.0%, 77.6%, 73.9% in Arms 1-3. BCAR incidence was significantly lower in Arm 2 versus 1 and 3 (p = 0.016, p = 0.039). AEs were comparable. Prolonged-release tacrolimus (0.15-0.175mg/kg/day) immediately posttransplant plus basiliximab and MMF (without maintenance corticosteroids) was associated with lower tacrolimus exposure, and significantly reduced renal function impairment and BCAR incidence versus prolonged-release tacrolimus (0.2mg/kg/day) administered immediately posttransplant. Delayed higher-dose prolonged-release tacrolimus initiation significantly reduced renal function impairment compared with immediate posttransplant administration, but BCAR incidence was comparable.

mTORC1/2 targeted by n-3 polyunsaturated fatty acids in the prevention of mammary tumorigenesis and tumor progression

Although epidemiological and preclinical studies have shown the preventative effects of n-3 polyunsaturated fatty acids (PUFAs) on breast cancer, inconsistencies still remain in the data and the underlying mechanisms remain unclear. In this study, we identified mammalian target of rapamycin (mTOR) signaling, which plays an essential role in cell proliferation and breast tumorigenesis, as a target of n-3 PUFAs. In breast cancer cell lines, n-3 PUFAs rapidly and efficiently suppress both mTOR complex 1 (mTORC1) and mTORC2 and their downstream signaling, and subsequently inhibit cell proliferation and angiogenesis while promoting apoptosis. Further study indicates that stabilization of the mTOR-raptor complex by n-3 PUFAs may contribute to their inhibitory effect on mTORC1. Importantly, four complementary and well-controlled animal models were utilized to identify the role and molecular target of n-3 PUFAs in the prevention of breast carcinogenesis and progression, namely: (1) chemically induced mammary tumor rats with a high dietary intake of n-3 PUFAs; (2) nude mice implanted with mammary tumor cell lines stably expressing fat-1, a desaturase that catalyzes the conversion of n-6 to n-3 PUFAs and produces n-3 PUFAs endogenously; (3) fat-1 transgenic severe combined immune deficiency mice implanted with breast tumor cells; and (4) the fat-1 transgenic mouse mammary tumor virus-polyoma virus middle T oncogene double-hybrid mice, a model of aggressive breast cancer. In summary, dietary and endogenous n-3 PUFAs abrogate the activity of mTORC1/2 pathways in vitro and in vivo and prevent breast carcinogenesis, tumor growth and metastasis. Taken together, our findings convincingly clarify the causal relationship between n-3 PUFAs and breast cancer prevention and establish mTORC1/2 as a target of n-3 PUFAs.

Asymmetric dimethylarginine attenuates serum starvation-induced apoptosis via suppression of the Fas (APO-1/CD95)/JNK (SAPK) pathway

Asymmetric dimethylarginine (ADMA) is synthesized by protein arginine methyltransferases during methylation of protein arginine residues and released into blood upon proteolysis. Higher concentrations of ADMA in blood have been observed in patients with metabolic diseases and certain cancers. However, the role of ADMA in colon cancer has not been well investigated. ADMA serum levels in human patients diagnosed with colon cancer were found to be higher than those present in healthy subjects. ADMA treatment of LoVo cells, a human colon adenocarcinoma cell line, attenuated serum starvation-induced apoptosis and suppressed the activation of the Fas (APO-1/CD95)/JNK (SAPK) (c-Jun N terminal protein kinase/stress-activated protein kinase)pathway. ADMA also suppressed the activation of JNK triggered by death receptor ligand anti-Fas mAb and exogenous C₂-ceramide. Moreover, we demonstrated that ADMA pretreatment protected LoVo cells from doxorubicin hydrochloride-induced cell death and activation of the Fas/JNK pathway. In summary, our results suggest that the elevated ADMA in colon cancer patients may contribute to the blocking of apoptosis of cancer cells in response to stress and chemotherapy.

The expression of 11β-HSDs, GR, and H6PDH in subcutaneous adipose tissue from polycystic ovary syndrome subjects

The aim of the work was to investigate the expression of 11β-hydroxysteroid dehydrogenase (11β-HSD) type 1 and 2, hexose-6-phosphate dehydrogenase (H6PDH), and glucocorticoids receptor (GR) mRNA in subcutaneous adipose tissue (SAT) from obese women with or without polycystic ovary syndrome (PCOS), and the association between their expression and the adipocytokines' concentration. Sixteen women with PCOS (group P) and 18 age- and BMI-matched control women (group C) were enrolled for the study. Subcutaneous adipose tissue was collected from the abdomen. The genes' expression was detected by real-time PCR, and the adipocytokines' concentration was measured by ELISA. Peripheral insulin sensitivity was assessed by homeostatic assessment model of insulin resistance (HOMA-IR). β-cell function was assessed by homeostasis model assessment of β-cell function (HOMA-IS). The expression of 11β-HSD1 mRNA was significantly higher in PCOS subjects (p<0.05) than controls; there was no difference for the expression of 11β-HSD2, GR, and H6PDH mRNA between the 2 groups. The stepwise multiple linear regression analysis showed that the mRNA level of 11β-HSD1 was positively correlated to the concentration of the serum tumor necrosis factor-alpha (TNF-α). Expression of 11β-HSD1 mRNA was increased in the SAT from the women with PCOS, which may contribute to the increased local active glucocorticoids (cortisol), and subsequently affects the secretion of the local adipose tissue.

Potential metabolite markers of schizophrenia

Schizophrenia is a severe mental disorder that affects 0.5-1% of the population worldwide. Current diagnostic methods are based on psychiatric interviews, which are subjective in nature. The lack of disease biomarkers to support objective laboratory tests has been a long-standing bottleneck in the clinical diagnosis and evaluation of schizophrenia. Here we report a global metabolic profiling study involving 112 schizophrenic patients and 110 healthy subjects, who were divided into a training set and a test set, designed to identify metabolite markers. A panel of serum markers consisting of glycerate, eicosenoic acid, β-hydroxybutyrate, pyruvate and cystine was identified as an effective diagnostic tool, achieving an area under the receiver operating characteristic curve (AUC) of 0.945 in the training samples (62 patients and 62 controls) and 0.895 in the test samples (50 patients and 48 controls). Furthermore, a composite panel by the addition of urine β-hydroxybutyrate to the serum panel achieved a more satisfactory accuracy, which reached an AUC of 1 in both the training set and the test set. Multiple fatty acids and ketone bodies were found significantly (P<0.01) elevated in both the serum and urine of patients, suggesting an upregulated fatty acid catabolism, presumably resulting from an insufficiency of glucose supply in the brains of schizophrenia patients.

Clinical utility of serum matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 concentrations in the assessment of liver fibrosis due to chronic hepatitis B

OBJECTIVE

To explore the relationships between serum concentrations of tissue inhibitor of metalloproteinase-2 (TIMP-2) and matrix metalloproteinase-2 (MMP-2), and severity of liver fibrosis in chronic hepatitis B.

METHODS

A total of 101 patients with hepatitis B and 54 healthy control subjects were consecutively enrolled. Serum MMP-2 and TIMP-2 were quantified by enzyme-linked immunosorbent assay.

RESULTS

Serum MMP-2 concentrations in patients with stage F2 - F4 fibrosis were significantly higher than in patients with stage F0 - F1 fibrosis and control subjects, but no significant difference was found between patients with stage F0 - F1 fibrosis and control subjects. Significant differences in serum TIMP-2 concentrations were found between patients with stages F2 - F4 and F0 - F1 fibrosis, and between stages F0 - F1 fibrosis and healthy control subjects. Areas under the receiver operating characteristic curves of serum TIMP-2 and MMP-2 for predicting clinically significant fibrosis (stage F2 - F4) were 0.899 and 0.770, respectively.

CONCLUSION

Serum TIMP-2 and MMP-2 assessment may represent a valuable noninvasive diagnostic test for liver fibrosis in hepatitis B.

Mechanisms of smooth muscle responses to inflammation

BACKGROUND

Inflammation-induced changes in smooth muscle may be the consequence of changes in the properties of smooth muscle itself, in the control by nerves and hormones, in the microenvironment, or in the balance of constitutive or induced mediators. A general concept is that the specific characteristics and effects of inflammation can be linked to the nature of the infiltrate and the associated mediators, which are dictated predominantly by the immune environment. Inflammatory mediators may regulate smooth muscle function by directly acting on smooth muscle cells or, indirectly, through stimulation of the release of mediators from other cells. In addition, smooth muscle is not a passive bystander during inflammation and our knowledge of molecular signaling pathways that control smooth muscle function, and the contribution of the immune mechanisms to smooth muscle homeostasis, has expanded greatly in the last decade. Recent studies also demonstrated the relevance of extracellular proteases, of endogenous or exogenous origin, redox imbalance, or epigenetic mechanisms, to gastrointestinal dismotility and inflammation in the context of functional and organic disorders.

PURPOSE

In this review we discuss the various types of inflammation and the established and emerging mechansims of inflammation-induced changes in smooth muscle morphology and function.

Preoperative transcatheter arterial chemoembolization (TACE) and chemotherapy for hepatic colorectal metastases: Impact on hepatic histology and postoperative outcome

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Background: The objective was to evaluate the effect of preoperative administration of TACE and chemotherapy on hepatic injury and on postoperative outcome in patients with colorectal liver metastases (CRM) Methods: Seventy seven patients underwent hepatic resection for CRM between January 1999 and December 2007 were evaluated. Pathologic review of the non-tumorous liver was performed using established criteria for steatosis, steatohepatitis, and sinusoidal dilation. The effect of two different treatment and hepatotoxicity on postoperative outcome was analyzed. Results: 40 patients (51.9%) received no preoperative treatment, where 27 patients (35.0%) received preoperative chemotherapy, 10 patients (12.9%) performed TACE before resection. The median duration of TACE group was 4.5 months (range, 1–6 months), where the median duration of chemotherapy group was 5 cycles (range, 2–9 cycles). Chemotherapy regimen consisted of oxalipaltin plus FU (29.9%), or irinotecan plus FU (5.2%). On pathologic analysis, 36 patients (46.7%) had steatosis, 24 (31.1%) had sinusoidal dilation, and 8 (10.3%) had steatohepatitis. TACE was associated with steatosis, steatohepatosis and postoperative complication, when compared with no chemotherapy (all p<0.05).Among chemotherapy group,Oxaliplatin was associated with steatohepatitis compared with no preoperative treatment (13.0% v 0%, respectively; p<0.05). Irinotecan was associated with steatohepatitis compared with no preoperative treatment (50% v 0%, respectively; p=0.0006). Patients with preoperative chemotherapy had increased steatohepatitis compared with no treatment group (18.5% v 0%, respectively, p=0.0008), the postoperative morbility rate in preoperative chemotherapy (25.9%) was double that of the no-chemotherapy (12.5%), but this difference was not statistically significant (p=0.20). Preoperative chemotherapy was also not associated with 90-day mortality. Conclusions: Preoperative TACE treatment may cause pathological liver injury, and increase postoperative morbility after hepatic surgery. The standard preoperative chemotherapy regimen with Oxaliplatin or Irinotecan may increase steatohepatis.

No significant financial relationships to disclose.

Identification of a Novel Valosin-Containing Protein Polymorphism in Late-Onset Alzheimer’s Disease

BACKGROUND/AIMS

Recently, mutations in the valosin-containing protein gene (VCP) were found to be causative for a rare form of dementia [Watts GDJ, et al.: Nat Genet 2004;36:377-381]. This gene lies within a region on the genome that has been linked to late onset Alzheimer's disease (LOAD) [Myers A, et al.: Am J Med Genet 2002;114:233-242]. In this study, we investigated whether variation within VCP could account for the LOAD linkage peak on chromosome 9.

METHODS

We sequenced 188 individuals from the set of sibling pairs we had used to obtain the linkage results for chromosome 9 to look for novel polymorphisms that could explain the linkage signal. Any variant that was found was then typed in 2 additional sets of neuropathologically confirmed samples to look for associations with Alzheimer's disease.

RESULTS

We found 2 variants when we sequenced VCP. One was a novel rare variant (R92H) and the other is already reported within the publicly available databases (rs10972300). Neither explained the chromosome 9 linkage signal for LOAD.

CONCLUSIONS

We have found a novel rare variant within the VCP gene, but we did not find a variant that could explain the linkage signal for LOAD on chromosome 9.

Durable clinical responses in patients (pts) with ovarian carcinoma treated on a phase II trial of autologous dendritic cells (DC) pulsed with MUC1

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Background: Mucin 1 (MUC1) is a glycoprotein highly expressed by ovarian carcinoma and is thus a potential antigen for immunotherapy. Following successful phase I results (Loveland et al. Clin Can Res 2006; 12:869), using DC pulsed with mannan-MUC1 fusion protein (DC-MFP), we report a phase II trial in similarly treated pts with ovarian carcinoma. Methods: Eligibility: incurable disease; age = 18 yrs; PS 0–2; no autoimmune disorders; rising CA125 levels (= 25% in 1 mth, confirmed). The primary endpoint was CA125 response (major = 50%, minor = 25%, each confirmed at = 4 wk) or stabilisation (= 3 mths). PBMC were collected by leukapheresis, cultured with IL-4 and GM-CSF to generate DC, and pulsed with MFP on d5. DC were reinjected on d6 as 8 i.d. injections (each 5x106), given 4-weekly × 3, then 10- weekly to 12 mths. Excess cells were cryopreserved for subsequent injections. Results: 28 pts were recruited, with all evaluable for toxicity and 21 for efficacy (received = 3 vaccinations). Characteristics were: serous histology 24 (86%) pts; median age 58 yrs (34–78); PS 0–1 27 (96%) pts; prior systemic therapy (all pts platinum-treated) 1 line 5 pts, 2 line 4 pts, 3 line 10 pts, = 4 lines 9 pts. Leukapheresis was generally required only 6-monthly. Following ex vivo culture, the proportion of CD86+ cells ranged from 40 - 85%. There was no grade = 3 therapy-related toxicity. Of 21 pts, 4 (19%) showed CA125 response or stabilisation. 2 pts had major response: 1 pt with 4 previous lines of systemic therapy (DC-MFP response duration 12+ mths) and 1 pt treated second line (duration 14 mths). One pt had stable disease of 7 mths duration which included 10 wks classified as minor response and one pt, treated fifth-line, had stable disease for 5 mths. An additional pt, treated fourth-line, had >25% CA125 reduction which was not confirmed by repeat CA125. CT scan results were generally concordant with CA125 status. No relationship was seen between clinical benefit and HLA type. 88% of tumours were MUC1+ on IHC. Conclusions: Study treatment was well tolerated and acceptable to pts. There was clear evidence of clinical benefit, including pts who were heavily pre-treated. This approach warrants further study in ovarian carcinoma. Supported by grants from PrimaBiomed Ltd.

No significant financial relationships to disclose.

Folate status and risk of colorectal polyps in African Americans

Dietary folate status appears to influence risk for colorectal cancer possibly by alterations in DNA methylation and nucleotide precursor pools. Polymorphisms (677C-->T and 1298A-->C) in methylenetetrahydrofolate reductase (MTHFR), a key enzyme in folate metabolism, determines enzyme activity. The frequency of polymorphisms in the gene varies extensively in different populations. We sought to determine the association between folate status, folate metabolism, DNA methylation, tobacco, alcohol consumption, and the risk of colorectal adenomas in African Americans. Among 58 patients who underwent a clinically indicated colonoscopy, 23 patients with histology confirmed colorectal polyps and 35 patients without were recruited for a case-control study. Blood samples were collected from fasting patients for determination of serum and red blood cell (RBC) folate, homocysteine, vitamin B(12), and methylation status. Polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) technique was performed to identify the MTHFR 677 C-->T polymorphism and specific PCR was used to analyze adenomatous polyposis coli (APC) gene-promoter sequence methylation. Among 23 cases, 49 polyps (adenomatous, n = 41 and hyperplastic, n= 8) were identified. Twenty-eight (57%) of the polyps were on the left side and 21 (42%) were on the right side of the colon. There was no association between the presence of colon polyps and levels of folate (serum, RBC), vitamin B(12), or homocysteine. Forty-eight individuals (84%) were homozygous for 677 CC. Of these individuals, 18 (37.5%) had >/=1 colorectal polyps, whereas 30 (62.5%) had no polyps. Nine individuals were heterozygous for 677 CT, and 4 (44%) of these individuals had colon polyps. Eighty-eight percent of the APC gene-promoter sequences tested using peripheral blood DNA from patients were unmethylated. Among the individuals who showed APC methylation, 66% had polyps; 33% were polyp free using their blood DNA. There was highly significant association between smoking and alcohol consumption with the presence of a colon polyp (P= .0006 and P= .05, respectively). In conclusion, the lack of the 677 TT may be a significant risk factor for colon neoplasm in the African-American population. Smoking and alcohol consumption were found to be risk factors for colon polyps. APC gene-promoter sequence methylation found in peripheral blood may be an indicator of risk for polyp formation and an important screening tool.

Scanning probe technology in metalloprotein and biomolecular electronics

The interfacing of man-made electronic components with specifically-folded biomacromolecules lies central not only to the development of sensory interfaces and potential new molecular-scale devices, but also enables us to analyse processes of great biological importance in a refined and controllable manner. Recent advances in both available technology, most notably optical and scanning probes in nature, and our understanding of suitable methodologies, have led us to the point where the characteristics of single biological molecules can be interrogated with good levels of reproducibility. We review here the application of scanning probe microscopy to the analysis of and experimentation on biological redox systems. Within this paper the tunnel transport characteristics, as assayed by both scanning tunnelling microscopy (STM) and conducting probe atomic force microscopy (AFM), of single metalloproteins are discussed. In a specific case study the electron transfer characteristics of the blue copper metalloprotein, azurin, are reported. The modulation of these properties under the influence of calibratable compressional force has also been examined in some detail. Work such as this enables one to reproducibly establish the conductance, barrier height, environmental sensitivity and electromechanical properties of these molecules.