Causal association between serum 25-hydroxyvitamin D levels and right ventricular structure and function: A Mendelian randomization study

BACKGROUND AND AIM

Deficient concentrations of vitamin D have been linked to several cardiovascular conditions, but the causal relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and right ventricular structure and function remains unclear. Mendelian randomization (MR) was employed to inspect this association.

METHODS AND RESULTS

Genetic instrumental variables associated with 25(OH)D levels were acquired from genome-wide association studies (GWAS) analyses. Summary statistics for right ventricular structure and function, including right ventricular end diastolic volume, right ventricular end systolic volume, right ventricular stroke volume, and right ventricular ejection fraction, were acquired from publicly available GWAS datasets. For the primary analysis, the inverse variance weighted (IVW) method was utilized in performing the MR analysis. Additionally, secondly analyses were conducted to estimate the robustness and consistency of the attained conclusions. The MR analysis did not reveal a considerable causal association between serum 25(OH)D levels and right ventricular end diastolic volume (β: 0.112, 95% confident interval [CI]: -0.006 to 0.230, p = 0.063), right ventricular end systolic volume (β: 0.102, 95% CI: -0.021 to 0.226, p = 0.105), right ventricular stroke volume (β: 0.095, 95% CI: -0.018 to 0.207, p = 0.099), or right ventricular ejection fraction (β: -0.005, 95% CI: -0.123 to 0.112, p = 0.928).

CONCLUSIONS

Our findings did not reveal any substantial evidence supporting a causal relationship between serum 25(OH)D levels and the structure and function of the right ventricle. These findings suggest that serum 25(OH)D levels may not directly influence right ventricular parameters assessed.

Association between basal metabolic rate and cardio-metabolic risk factors: Evidence from a Mendelian Randomization study

Background

Cardio-metabolic risk factors play a crucial role in the development of cardiovascular and metabolic diseases. Basal metabolic rate (BMR) is a fundamental physiological parameter that affects energy expenditure and might contribute to variations in these risk factors. However, the exact relationship between BMR and cardio-metabolic risk factors has remained unclear.

Methods

We employed Mendelian Randomization (MR) analysis to explore the association between BMR (N: 534,045) and various cardio-metabolic risk factors, including body mass index (BMI, N: 681,275), fasting glucose (N: 200,622), high-density lipoprotein (HDL) cholesterol (N = 403,943), low-density lipoprotein (LDL) cholesterol (N = 431,167), total cholesterol (N: 344,278), and triglycerides (N: 441,016), C-reactive protein (N: 436,939), waist circumference (N: 232,101), systolic blood pressure (N: 810,865), diastolic blood pressure (N: 810,865), glycated haemoglobin (N: 389,889), and N-terminal prohormone brain natriuretic peptide (N: 21,758). We leveraged genetic variants strongly associated with BMR as instrumental variables to investigate potential causal relationships, with the primary analysis using the Inverse Variance Weighted (IVW) method.

Results

Our MR analysis revealed compelling evidence of a causal link between BMR and specific cardio-metabolic risk factors. Specifically, genetically determined higher BMR was associated with an increased BMI (β = 0.7538, 95% confidence interval [CI]: 0.6418 to 0.8659, p < 0.001), lower levels of HDL cholesterol (β = -0.3293, 95% CI: 0.4474 to -0.2111, p < 0.001), higher levels of triglycerides (β = 0.1472, 95% CI: 0.0370 to 0.2574, p = 0.0088), waist circumference (β = 0.4416, 95% CI: 0.2949 to 0.5883, p < 0.001), and glycated haemoglobin (β = 0.1037, 95% CI: 0.0080 to 0.1995, p = 0.0377). However, we did not observe any significant association between BMR and fasting glucose, LDL cholesterol, total cholesterol, C-reactive protein, systolic blood pressure, diastolic blood pressure, or N-terminal prohormone brain natriuretic peptide (all p-values>0.05).

Conclusion

This MR study provides valuable insights into the relationship between BMR and cardio-metabolic risk factors. Understanding the causal links between BMR and these factors could have important implications for the development of targeted interventions and therapies.

Systolic blood pressure is associated with abnormal alterations in brain cortical structure: Evidence from a Mendelian randomization study

BACKGROUND

Hypertension has been recognized as a significant risk factor for cerebrovascular diseases and cognitive decline. However, the specific impact of hypertension, systolic/diastolic blood pressure, pulse pressure (PP) and mean arterial pressure (MAP) on brain cortical structure remains unclear. Mendelian randomization (MR) provides a robust approach to investigate the causal relationship between blood pressure components and brain cortical changes.

METHODS

In this MR study, data from large-scale genome-wide association studies for blood pressure components and neuroimaging were utilized to conduct our analyses. We leveraged genetic variants associated specifically with hypertension (122,620 cases and 332,683 controls), systolic (469,767 individuals), diastolic (490,469 individuals) blood pressure, PP (810,865 individuals) and MAP (over 1 million individuals) to evaluate their effects on brain cortex surficial area (51,665 individuals) and cortex thickness (51,665 individuals).

RESULTS

Our findings revealed a significant correlation between systolic blood pressure and abnormal reduction in brain cortex surficial area (β=-1330.69, 95% confident interval [CI]: -2655.35 to -6.02, p = 0.0489); however, no significant relationship was found between systolic blood pressure and brain cortex thickness (β=-0.0078, 95% CI: -0.0178 to 0.0022, p = 0.1287). Additionally, no significant associations were observed between hypertension (β=-200.05, p = 0.6884; β=-0.0051, p = 0.1179, respectively), diastolic blood pressure (β=-460.63, p = 0.5160; β=0.0047, p = 0.2448, respectively), PP (β=1041.84, p = 0.3725; β=-0.0112, p = 0.2212, respectively), MAP (β=-18.84, p = 0.8841; β=0.0002, p = 0.7654, respectively) and both brain cortex surficial area and brain cortex thickness.

CONCLUSION

Our MR study provides evidence supporting the hypothesis that systolic blood pressure, rather than diastolic blood pressure, PP or MAP, is associated with abnormal changes in brain cortical structure.

Elevated mean arterial pressure is associated with a lower risk of mortality in acute kidney injury patients receiving continuous renal replacement therapy

OBJECTIVE

maintenance of an appropriate mean arterial pressure (MAP) is important for critically ill patients. However, the association between MAP and prognosis in acute kidney injury (AKI) patients receiving continuous renal replacement therapy (CRRT) is thus far unclear.

MATERIALS AND METHODS

a total of 1,144 AKI patients who had received CRRT between January 2009 and September 2016 were enrolled and their MAP was measured at CRRT initiation. Patients were categorized into four groups (Quartile 1: MAP < 67.3 mmHg; Quartile 2: 67.3 ≤ MAP < 76.7 mmHg; Quartile 3: 76.7 ≤ MAP < 86.3 mmHg; Quartile 4: MAP ≥ 86.3 mmHg), and 28- and 90-day mortality rates were compared.

RESULTS

our results demonstrate that 204 (72.1%), 187 (63.4%), 174 (62.6%), and 145 (50.3%) deaths occurred in quartiles 1, 2, 3, and 4 within 28 days, respectively (p < 0.001). This trend also exists in 90-day mortality (Quartile 1: 81.3%; Quartile 2: 72.5%; Quartile 3: 72.3%; Quartile 4: 61.1%, p < 0.001). The Kaplan-Meier results indicate that higher MAP is associated with a reduction in 28- and 90-day mortality (both p < 0.001). After adjusting for potential confounders using Cox proportional hazard regression analysis, higher MAP was still associated with a decline in 28 - and 90-day mortality (both p < 0.001).

CONCLUSION

MAP is a valuable parameter for predicting mortality in AKI patients who are receiving CRRT.

Biomaterials / bioinks and extrusion bioprinting

Bioinks are formulations of biomaterials and living cells, sometimes with growth factors or other biomolecules, while extrusion bioprinting is an emerging technique to apply or deposit these bioinks or biomaterial solutions to create three-dimensional (3D) constructs with architectures and mechanical/biological properties that mimic those of native human tissue or organs. Printed constructs have found wide applications in tissue engineering for repairing or treating tissue/organ injuries, as well as in vitro tissue modelling for testing or validating newly developed therapeutics and vaccines prior to their use in humans. Successful printing of constructs and their subsequent applications rely on the properties of the formulated bioinks, including the rheological, mechanical, and biological properties, as well as the printing process. This article critically reviews the latest developments in bioinks and biomaterial solutions for extrusion bioprinting, focusing on bioink synthesis and characterization, as well as the influence of bioink properties on the printing process. Key issues and challenges are also discussed along with recommendations for future research.

[Clinical characteristics of recurrent appendicitis]

Objective: To analyze clinical characteristics of recurrent appendicitis. Methods: A retrospective cohort study was carried out. Clinical data of patients who underwent appendectomy due to acute appendicitis confirmed by pathology in the Affiliated Hospital of Qingdao University from January 2011 to December 2015 were analyzed retrospectively. Exclusion criteria: (1) age of less than 18 years;(2) chronic appendicitis; (3) periappendiceal abscess; (4) appendiceal mucocele or mucinous neoplasms; (5) appendiceal neuroendocrine tumors or cancers; (6) appendicitis during pregnancy; (7) concurrent AIDS, hematological disease, autoimmune disease, inflammatory bowel disease or advanced cancer; (8) other simultaneous surgery. A total of 373 patients were enrolled the study. These patients were divided into the recurrent group (133 cases) and the first episode group (240 cases) according to the previous history of antibiotic therapy for acute appendicitis. The prevalence of recurrent appendicitis was calculated, and the clinical characteristics were analyzed, including gender, age, comorbidities and preoperative CT images. Results: Of 373 patients, 209 were male and 164 were female, with a median age of 42 (18 to 88) years. Median recurrent time of the recurrent group was 4 (1 to 60) months. Compared to the first episode group, the recurrent group had higher proportion of age <50 years [71.4% (95/133) vs. 57.5% (138/240), χ(2)=7.081, P=0.008], higher proportion of concurrent diabetes [13.5% (18/133) vs. 5.4% (13/240), χ(2)=7.399, P=0.007], shorter onset time [(41.7±13.6) hours vs. (59.4±56.2) hours, t=-3.286, P=0.001], lower proportion of abdominal tension and rebound pain [57.9% (77/133) vs. 66.7% (160/240), χ(2)=5.065, P=0.024], lower score of modified Alvarado score [(5.6±1.9) point vs. (6.1±1.9) point, t=-2.417, P=0.016], lower WBC count [(10.5±4.6) ×10(9)/L vs. (11.5±4.5)×10(9)/L, t=-1.190, P=0.047], higher percentage of lymphocyte [(19.4±14.7)% vs. (16.1±13.3)%, t=2.069, P=0.039]. In the recurrent group, ratio of length of removed appendix ≥7 cm was higher as compared with the first episode group [44.4% (59/133) vs. 32.9% (79/240), χ(2)=4.808, P=0.028], while the ratio of complicated appendicitis was significantly lower [8.3% (11/133) vs. 22.9% (55/240), χ(2)=10.823, P=0.001]. CT images were available in 129 patients, intraluminal appendicoliths was found in 19 of 50 patients (38%) in the recurrent group, while in 16 of 79 patients (20.3%) in the first episode group, and there was statistically significant difference between the two groups (χ(2)=4.880, P=0.027). Conclusions: Clinical characteristics of recurrent acute appendicitis include age less than 50 years, concurrent diabetes, short onset time, less abdominal tension or rebound pain, low modified Alvarado score, low WBC count, high percentage of lymphocyte, appendix length longer than 7 cm, non-complicated appendicitis and intraluminal appendicoliths.

[Clinical characteristics and related factors of somatization symptoms in outpatients with psychiatric disorders of the department of cardiology in general hospitals]

Objective: To explore the clinical characteristics and related factors of somatization symptoms in outpatients with psychiatric disorders of the cardiology department in general hospital. Methods: Cross-sectional survey method was used in this study. From August 2017 to September 2018, 508 outpatients of our department with suspected mental disorders, who complained of physical discomfort and screened by the "Three Questions" method recommended by the Chinese Expert Consensus on Psychological Prescriptions of Cardiovascular Patients in 2014, were consecutively included. General Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire (PHQ-9), Patient Health Questionnaire-15 (PHQ-15) and self-made general demographic questionnaire (including age, sex, marital status, educational level, occupation, duration of disease, clinical diagnosis and the process of medical treatment for the main somatic symptoms in recent one year) were used to investigate these patients, under the assistance of unified training psychological consultants. The detection rate of anxiety and depression, the degree and distribution of somatization symptoms in outpatients with mental disorders were analyzed, and the related factors affecting the occurrence of somatization symptoms were screened by multivariate logistic regression. Results: The selected patients were (51.3±10.1) years old, of which 37.8% (192/508) were males and 62.2% (316/508) were females. The total detection rate of anxiety/depression was 86.8% (441/508), and the detection rate of somatization symptoms was 93.1% (473/508). The number of positive symptom items in PHQ-15 was 8.0±2.7, and the detection rate of anxiety/depression was 78.6% (372/473) in patients with somatization symptoms. There were significant differences in the proportion of women, the average number of outpatient visits and hospitalizations in the past one year, GAD-7 score and PHQ-9 score among the patients with mild, moderate and severe somatization symptoms (all P<0.05). PHQ-15 score was positively correlated with GAD-7 score (r=0.524 5, P<0.001) and PHQ-9 score (r=0.574 9, P<0.001) in patients with somatization symptoms. Stepwise logistic regression analysis showed that total scores of PHQ-9 (OR=8.020, 95%CI 3.470-18.930, P<0.001) and GAD-7 (OR=6.526, 95%CI 2.903-13.045, P<0.001) and female (OR=4.440, 95%CI 1.059-9.073, P=0.011) were related factors of somatizations. Conclusions: The incidence of somatization symptoms is high in patients with psychological disorders in outpatients of cardiology department in general hospital. Anxiety, depression and gender are the main related risk factors of somatization symptoms in this patient cohort. Degree of anxiety and depression increased in proportion to the severity of somatization symptoms. Anxiety, depression and female is related to somatization symptoms.

A modification and validation of quantitative morphometry classification system for osteoporotic vertebral compressive fractures in mainland Chinese

This study described a modified quantitative morphometry (mQM) system adapted to specific reference values for Mainland Chinese population. The mQM system is validated using the Genant Semiquantative system and is sensitive for detecting vertebral height changes and predicting cement leakage after percutaneous kyphoplasty (PKP) in patients with osteoporotic vertebral compressive fracture (OVCF).

INTRODUCTION

OVCF is a manifestation of osteoporosis. To improve clinical management of osteoporosis, the quantitative morphometry (QM) system has been widely used for the early diagnosis and precise classification of OVCF in developed countries. Here, we present an mQM system and validated its use in detecting OVCF in Mainland Chinese.

METHODS

Using our mQM system, the pre- and post-operative values of vertebral heights were measured and evaluated in 309 Mainland Chinese who received percutaneous kyphoplasty (PKP) as OVCF treatment. Measurements and classification of fractures from the mQM system were validated by comparing to values obtained by the Genant semiquantative (SQ) method. Moreover, we evaluated the sensitivity of the mQM system by its ability to detect restoration of vertebral heights and predict cement leakage after PKP.

RESULTS

The five classification of fractures, No deformity (ND), anterior wedge (AW), posterior wedge (PW), biconcavity (BC), and compression (CP), evaluated by the mQM method shared similar distribution characteristics compared to those obtained by the SQ method. In addition, mQM evaluation showed that the vertebra height of all fracture types showed significant restoration after PKP. The incidence of cement leakage was most common in CP (37.5%), followed by AW (31.6%), BC (26.5%), ND (23.7%), and PW (0.0%).

CONCLUSIONS

Our mQM system is suitable for classification of fractures, detection of vertebral height restoration, and correlation of cement leakage after PKP in Mainland Chinese population.

Advanced diffusion imaging for assessing normal white matter development in neonates and characterizing aberrant development in congenital heart disease

Background

Elucidating developmental trajectories of white matter (WM) microstructure is critically important for understanding normal development and regional vulnerabilities in several brain disorders. Diffusion Weighted Imaging (DWI) is currently the method of choice for in-vivo white matter assessment. A majority of neonatal studies use the standard Diffusion Tensor Imaging (DTI) model although more advanced models such as the Neurite Orientation Dispersion and Density Imaging (NODDI) model and the Gaussian Mixture Model (GMM) have been used in adult population. In this study, we compare the ability of these three diffusion models to detect regional white matter maturation in typically developing control (TDC) neonates and regional abnormalities in neonates with congenital heart disease (CHD).

Methods

Multiple b-value diffusion Magnetic Resonance Imaging (dMRI) data were acquired from TDC neonates (N = 16) at 38 to 47 gestational weeks (GW) and CHD neonates (N = 19) aged 37 weeks to 41 weeks. Measures calculated from the diffusion signal included not only Mean Diffusivity (MD) and Fractional Anisotropy (FA) derived from the standard DTI model, but also three advanced diffusion measures, namely, the fiber Orientation Dispersion Index (ODI), the isotropic volume fraction (Viso), and the intracellular volume fraction (Vic) derived from the NODDI model. Further, we used two novel measures from a non-parametric GMM, namely the Return-to-Origin Probability (RTOP) and Return-to-Axis Probability (RTAP), which are sensitive to axonal/cellular volume and density respectively. Using atlas-based registration, 22 white matter regions (6 projection, 4 association, and 1 callosal pathways bilaterally in each hemisphere) were selected and the mean value of all 7 measures were calculated in each region. These values were used as dependent variables, with GW as the independent variable in a linear regression model. Finally, we compared CHD and TDC groups on these measures in each ROI after removing age-related trends from both the groups.

Results

Linear analysis in the TDC population revealed significant correlations with GW (age) in 12 projection pathways for MD, Vic, RTAP, and 11 pathways for RTOP. Several association pathways were also significantly correlated with GW for MD, Vic, RTAP, and RTOP. The right callosal pathway was significantly correlated with GW for Vic. Consistent with the pathophysiology of altered development in CHD, diffusion measures demonstrated differences in the association pathways involved in language systems, namely the Uncinate Fasciculus (UF), the Inferior Fronto-occipital Fasciculus (IFOF), and the Superior Longitudinal Fasciculus (SLF). Overall, the group comparison between CHD and TDC revealed lower FA, Vic, RTAP, and RTOP for CHD bilaterally in the a) UF, b) Corpus Callosum (CC), and c) Superior Fronto-Occipital Fasciculus (SFOF). Moreover, FA was lower for CHD in the a) left SLF, b) bilateral Anterior Corona Radiata (ACR) and left Retrolenticular part of the Internal Capsule (RIC). Vic was also lower for CHD in the left Posterior Limb of the Internal Capsule (PLIC). ODI was higher for CHD in the left CC. RTAP was lower for CHD in the left IFOF, while RTOP was lower in CHD in the: a) left ACR, b) left IFOF and c) right Anterior Limb of the Internal Capsule (ALIC).

Conclusion

In this study, all three methods revealed the expected changes in the WM regions during the early postnatal weeks; however, GMM outperformed DTI and NODDI as it showed significantly larger effect sizes while detecting differences between the TDC and CHD neonates. Future studies based on a larger sample are needed to confirm these results and to explore clinical correlates.

Prevalence of chronic kidney disease in patients with chronic hepatitis B: A cross-sectional survey

Renal safety is a major concern during long-term antiviral treatment for chronic hepatitis B (CHB). This study aimed to investigate the prevalence of chronic kidney disease (CKD) in patients with CHB that had been treated with antiviral therapy. This was a single-centre, cross-sectional study in a real-life cohort in which all patients received antiviral treatment. Serum creatinine-based equations from the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) were used to estimate the glomerular filtration rate (GFR). CKD was defined as an eGFR <60 mL/min/1.73 m² or a urinary albumin to creatinine ratio ≥ 3 mg/mmol (defined as albuminuria). Univariate and multivariate analyses were conducted to determine the risk factors of CKD. A total of 1985 patients were included in the analysis from February 2015 to December 2015. The mean age and median duration of antiviral treatment was 42.20 years and 17.05 months, respectively. The overall prevalence of CKD was 7.9% (157/1985), with 44 patients experiencing decreased renal function (eGFR less than 60 mL/min/1.73 m²) and 129 patients with albuminuria. Patients with cirrhosis had a higher prevalence of a decreased GFR (4.3% vs 1.6%, P<.001) and albuminuria (11.1% vs 5.2%, P<.001) than those without cirrhosis. In the multivariate analysis, hypertension (Odds Ratio [OR] 4.564, P<.001), diabetes mellitus (OR 2.688, P<.001) and cirrhosis (OR 1.918, P<.001) were independent factors associated with the presence of CKD. CKD was a clinically significant comorbidity in patients with CHB. Special attention should be paid to cirrhotic patients and patients with the metabolic syndrome.

Hypertension might be a risk factor for erectile dysfunction: a meta-analysis

The study aimed to evaluate whether hypertension was a risk factor for erectile dysfunction (ED). Databases including PubMed and Embase were retrieved to identify studies related to hypertension in ED patients. Odds ratio (OR) and 95% confidence interval (CI) were used as the effect size. Subgroup analyses stratified by total number of enrolled subjects and research regions were performed. Sensitivity analysis was performed by removing a single study at one time. Egger's test was used to evaluate the publication bias. Totally, 40 studies including 121,641 subjects were included in the meta-analysis. As a result, hypertension was closely related to ED (OR = 1.74, 95% CI, 0.63-0.80, p < .01). Subgroup analysis indicated hypertension was the risk factor for ED whatever the participants numbers. When stratified by different regions, hypertension was a risk factor for ED in Africa (OR = 3.35, 95% CI, 1.45-7.77, p < .01), Americas (OR = 1.97, 95% CI, 1.68-2.31, p < 0.01), Asia (OR = 1.46, 95% CI, 1.16-1.84, p < .01) and Europe (OR = 1.83, 95% CI, 1.34-2.49, p < .01), but not in Australia. Hypertension may be a potential risk factor for ED.

Inter-site and inter-scanner diffusion MRI data harmonization

We propose a novel method to harmonize diffusion MRI data acquired from multiple sites and scanners, which is imperative for joint analysis of the data to significantly increase sample size and statistical power of neuroimaging studies. Our method incorporates the following main novelties: i) we take into account the scanner-dependent spatial variability of the diffusion signal in different parts of the brain; ii) our method is independent of compartmental modeling of diffusion (e.g., tensor, and intra/extra cellular compartments) and the acquired signal itself is corrected for scanner related differences; and iii) inter-subject variability as measured by the coefficient of variation is maintained at each site. We represent the signal in a basis of spherical harmonics and compute several rotation invariant spherical harmonic features to estimate a region and tissue specific linear mapping between the signal from different sites (and scanners). We validate our method on diffusion data acquired from seven different sites (including two GE, three Philips, and two Siemens scanners) on a group of age-matched healthy subjects. Since the extracted rotation invariant spherical harmonic features depend on the accuracy of the brain parcellation provided by Freesurfer, we propose a feature based refinement of the original parcellation such that it better characterizes the anatomy and provides robust linear mappings to harmonize the dMRI data. We demonstrate the efficacy of our method by statistically comparing diffusion measures such as fractional anisotropy, mean diffusivity and generalized fractional anisotropy across multiple sites before and after data harmonization. We also show results using tract-based spatial statistics before and after harmonization for independent validation of the proposed methodology. Our experimental results demonstrate that, for nearly identical acquisition protocol across sites, scanner-specific differences can be accurately removed using the proposed method.

Bone marrow lesions, subchondral bone cysts and subchondral bone attrition are associated with histological synovitis in patients with end-stage knee osteoarthritis: a cross-sectional study

OBJECTIVE

The aim of this study was to examine the osteoarthritis (OA)-related structural changes associated with histological synovitis in end-stage knee OA patients.

METHODS

Forty end-stage knee OA patients (female: 88%, mean age: 71.8 y) were enrolled. All participants underwent 3.0-T MRI. The structural changes, such as cartilage morphology, subchondral bone marrow lesion (BML), subchondral bone cyst (SBC), subchondral bone attrition (SBA), osteophytes, meniscal lesion and synovitis, were scored using the whole-organ MRI scoring (WORMS) method. Synovial samples were obtained from five regions of interest (ROIs) of the knee joint during total joint replacement surgery. The associations between the histological synovitis score (HSS) and WORMS or the synovial expression levels of cyclooxygenase (COX)-2, interleukin (IL)-1β, IL-6 and transforming growth factor (TGF)-β were examined using Spearman's correlation coefficient.

RESULTS

Among the seven OA-related structural changes, the BML, SBC, SBA and synovitis were significantly associated with the HSS (r = 0.33, 0.35, 0.48 and 0.36, respectively), while other morphological changes were not. Although synovial COX-2, IL-1β or IL-6 expression levels were not associated with the HSS, the synovial TGF-β expression levels were associated with the HSS.

CONCLUSION

The presence of BML, SBC and SBA was associated with histological synovitis in end-stage knee OA patients.

Does vitamin K2 play a role in the prevention and treatment of osteoporosis for postmenopausal women: a meta-analysis of randomized controlled trials

To identify the role of vitamin K2 for the prevention and treatment of osteoporosis in postmenopausal women, we conducted this meta-analysis of 19 randomized controlled trials. Our results showed that vitamin K2 might play a role in maintaining the bone mineral density and in reducing the incidence of fractures for postmenopausal women with osteoporosis.

INTRODUCTION

Vitamin K2 has been revealed to be effective in the prevention and treatment of osteoporosis in Japan, which was not confirmed in western countries. Thus, we conduct this meta-analysis to verify the hypothesis that vitamin K2 plays a role in the prevention and treatment of osteoporosis for postmenopausal women.

METHODS

We searched the Cochrane Library, Pub Med, EMBASE, and ISI web of knowledge (until December 1, 2013) and reference lists of eligible articles. A meta-analysis of all-including randomized controlled trials was then performed.

RESULTS

Nineteen randomized controlled trials encompassing 6759 participants have met the inclusion criteria. Subgroup analysis of postmenopausal women with osteoporosis revealed a significant improvement of vertebral BMD for both medium-term and long-term results favoring vitamin K2 group (p < 0.00001 and p = 0.0005). However, no significant difference in BMD changes was revealed for the non-osteoporosis subgroup analysis. As for the incidence of fractures, pooled analysis of the seven related studies demonstrated no significant difference in the incidence of fractures favoring vitamin K2 (RR = 0.63, p = 0.08). However, sensitivity analysis by rejecting the study inducing heterogeneity demonstrated a significant difference in the incidence of fractures favoring vitamin K2 (RR = 0.50, p = 0.0005). Significant differences were found in undercarboxylated osteocalcin reduction and osteocalcin increment. The result of adverse reaction analysis showed that vitamin K2 group seemed to have a higher adverse reaction rate (RR = 1.22, p = 0.06).

CONCLUSIONS

This meta-analysis seemed to support the hypothesis that vitamin K2 plays kind of a role in the maintenance and improvement of vertebral BMD and the prevention of fractures in postmenopausal women with osteoporosis. The reduction of undercarboxylated osteocalcin and increment of osteocalcin may have some relation to the process of bone mineralization. However, the effect of vitamin K2 for postmenopausal women without osteoporosis had not been identified. Further high-quality RCTs with large sample size are needed to confirm the role of vitamin K2 in osteoporosis for postmenopausal women.

Clinicopathological Features of Solitary Fibrous Tumours in the Extremities: Four Case Reports and a Literature Review

This paper reports on the clinicopathological features of four patients with solitary fibrous tumours arising from the extremities and presents a review of the relevant literature. The patients consisted of three women and one man, with a mean age of 47.8 years. Standard pre-operative work-up data were examined, including: history, clinical examination, plain radiography, computed tomography scans of the lesion and chest, magnetic resonance imaging, angiography, technetium-99m bone scan, thallium-201 scintigraphy and routine laboratory tests. Immunohisto chemical staining was performed for CD34, Bcl-2 protein, vimentin, S-100 protein, desmin and smooth muscle actin, and pathological material was reviewed for the presence of histologically malignant components. Immunohistochemically, all of the tumours were diffusely positive for CD34. Clinical and radiological findings of solitary fibrous tumours affecting the extremities are reminiscent of those of aggressive or malignant soft tissue tumours. Pathological and immunohistochemical studies are important in making the correct diagnosis.

Genetic Polymorphisms of MTHFR and Aberrant Promoter Hypermethylation of the RASSF1A Gene in Bladder Cancer Risk in a Chinese Population

Epidemiological studies have shown that folate deficiency increases the risk of cancer by affecting DNA repair and methylation. Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism. In this study, it was hypothesized that MTHFR (C677T and A1298C) polymorphisms would be associated with bladder cancer and also with hypermethylation of the promoter of the Ras association domain family 1A (RASSF1A) gene. This hospital-based, case-control study of 312 bladder cancer patients and 325 cancer-free controls found that individuals carrying the MTHFR 677TT genotype had a 2.00-fold increased risk of bladder cancer compared with those carrying the 677CC genotype. None of the MTHFR A1298C polymorphisms alone were associated with bladder cancer, but the combined haplotype 677TT/1298AA was associated with a 2.27-fold increased risk compared with haplotype 677CC/1298AA. There was no association between MTHFR gene variants and methylation status of the RASSF1A gene in the 45 bladder cancer patients in whom this was studied. It is concluded that the MTHFR 677TT genotype and the TTAA haplotype may increase the risk of bladder cancer.

A randomised clinical trial of transnasal endoscopy versus fluoroscopy for the placement of nasojejunal feeding tubes in patients with severe acute pancreatitis

OBJECTIVES

To compare transnasal endoscopy with fluoroscopy for the placement of nasojejunal feeding tubes (NJTs) in patients with severe acute pancreatitis.

METHODS

100 patients were randomised to receive NJTs by transnasal endoscopy or fluoroscopy. Successful placement was confirmed by abdominal radiograph.

RESULTS

The success rate was 96% using transnasal endoscopy and 94% using fluoroscopy (p>0.05). The mean (SEM) time to perform a successful procedure was 12.7 (5.1) min for transnasal endoscopy and 7.9 (5.9) min for fluoroscopy (p<0.05). No complications were reported using fluoroscopy, whereas there was one case of tachypnoea and four cases of abdominal distension related to transnasal endoscopy (p<0.05). For transnasal endoscopy, the mean (SEM) visual analogue scale comfort score was 3.2 (1.3) before, 8.7 (1.5) during, and 3.6 (1.3) after a successful procedure. The corresponding values for fluoroscopy were 3.1 (1.2), 5.4 (1.6) and 3.7 (1.4). The difference in scores during the procedure was significant (p<0.05).

CONCLUSIONS

Transnasal endoscopic and fluoroscopic placement of NJTs can safely and accurately be performed in patients with severe acute pancreatitis. The results of this study show no significant difference in success and complication rates between the two procedures. However, the procedure time for fluoroscopic placement was shorter than for transnasal endoscopic placement, and patients experienced less discomfort.

Circumcision and human papillomavirus infection in men: a site-specific comparison

BACKGROUND

Lack of circumcision has been identified as a risk factor for male genital human papillomavirus (HPV) infection, although this association has not been consistently supported.

METHODS

Specimens for HPV testing were collected from a cohort of 379 (primarily heterosexual) adult males. HPV prevalence in the glans penis and coronal sulcus, penile shaft, scrotum, semen, and urine was compared by circumcision status.

RESULTS

Overall, HPV DNA prevalence ranged from 6% in semen to 52% in the penile shaft. The prevalence of any HPV infection in the glans/corona was significantly higher in uncircumcised men (46%) than in circumcised men (29%) (odds ratio [OR], 1.96 [95% confidence interval (CI), 1.02-3.75], adjusted for demographic characteristics and sexual history). Uncircumcised men also had an increased risk of oncogenic HPV infection (adjusted OR, 2.51 [95% CI, 1.11-5.69]) and infection with multiple HPV types (adjusted OR, 3.56 [95% CI, 1.50-8.50]). Among uncircumcised men, HPV prevalence in the foreskin (44%) was comparable to that in the glans/corona, and type-specific positivity was observed between the 2 sites (kappa=0.52).

CONCLUSIONS

Uncircumcised men have an increased risk of HPV infection, including with oncogenic HPV, specifically localized to the glans/corona, possibly because of its proximity to the foreskin, which may be particularly vulnerable to infection.

Effects of different chemotherapy regimens and tamoxifen for HER2 over-expressed breast cancer adjuvant therapy

11048

Background: To evaluate effects of different adjuvant chemotherapy regimens and TAM in HER-2-overexpressed breast cancer patients. Methods: To study 1625 primary breast cancer cases after operation from 2002.7 to 2005.11 given adjuvant chemotherapy ,600 cases given CMF, 600 cases given CEF, and 425 cases given T-regimen (anthracyclines follow taxanes),1090 HR+ cases given tamoxifen. HER-2 expression were measured by immunohistochemistry (IHC). Median follow-up time is 42 months. Results: (1)3yr DFS of HER-2 over-expression is inferior to HER-2 negative ones in CMF group(p<0.05), no difference between HER-2- overexpressed and HER-2-negative group treated with either CEF or taxanes-based regimen (p>0.05). Subgroup analysis suggested: patients treated with CMF, 3yr DFS of HER-2 over-expression is inferior to HER-2-negative ones in node-positive subgroup, but no difference in node-negative ones; HER-2 expression has no influence on effects of CEF or T-regimen in node-positive or node-negative subgroup. (2) 425 HER-2 over-expressed patients(183 cases given CMF , 121 cases given CEF , and 121 cases given T-regimen): compared to CMF, anthracyclines and taxanes are more effective, but no difference between anthracyclines and T-regimen. (3) 235 patients with HER-2 over- expression and node-postive (72 cases given CMF , 68 cases given CEF, and 95 cases given T-regimen):, anthracyclines and taxanes are more effective than CMF, but no difference between anthracyclines and T-regimen. (4)3yr DFS is 91.23% in HER-2 over-expressed group and 93.42% in HER-2-negative group (p=0.04) with TAM. HER-2 over-expressed patients are resistant to TAM. (5) Subgroup analysis suggested that: 3yr DFS is 88.67% with HER-2 over-expression and 92.20% with HER-2-negative in postmenopausal node-positive subgroup(p=0.0069), postmenopausal patients with HER-2 over-expression and node-positve are resistant to TAM; no difference in either premenopausal or postmenopausal node-negative subgroup (p>0.05). Conclusions: No difference between Anthracyclines based and T-regimens for HER2 over-expressed patients with node-positive for 3yr DFS.Postmenopausal ER+/PR+ patients with HER2 over- expression are resistant to Tamoxifen endocrine therapy.

No significant financial relationships to disclose.

Preliminary analysis of biomarkers in plasma by SELDI to predict the response to EGFR tyrosine kinase inhibitors (TKIs) in NSCLC patients

7189

Background: The identification of NSCLC patients who are most likely to respond to EGFR tyrosine kinase inhibitors (TKIs) have been investigated intensively. Although screenings for EGFR mutation and gene copy number are promising, these tests are not yet widely available. New predictor markers are urgently needed. The objective of this study was to identify proteomic markers in plasma to predict benefits for patients treated with EGFR TKIs. Methods: Proteomic spectra derived from plasma samples from EGFR TKIs-responsive patients and non-responsive patients were generated by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). These proteomic spectra (WCX2 chips, Ciphergen Biosystems, Inc.) were then analyzed by comparing protein profiles in different response groups (PR Vs PD, training set). Another group of patients treaded with EGFR TKIs will be serving as testing set to validate the result of training set. Results: Totally, fifty-four advanced NSCLC patients were included in this study. All patients were treated with single agent of gefitinib or erlotinib. Twenty-nine patients were included in training set of this study. All were suitable for response evaluation. Ten patients (34.5%) were PR, 8 (27.6%) were SD, and 11 (37.9%) were progressive disease (PD). Total six significant protein peaks were significant (m/z 4288, 4595, 9191, 9349, 9397, and 9563) between PR group and PD group (table). Another twenty-five patients were included for testing set. Analyzing of testing set is still going on. Table shows PR and PD patients’ plasma comparison on WCX2 chips. Conclusions: This preliminary “training” set of spectra that uses SELDI-TOF MS technology found that six protein peaks seemed to be very important biomarkers to predict the response to gefitinib. Prospective tests to confirm these proteins and peptides will be present at this meeting. These results are promising for identifying new biomarkers of EGFR TKIs with SELDI.

[Table: see text]

No significant financial relationships to disclose.

Comparison of physician- and self-collected genital specimens for detection of human papillomavirus in men

There is currently no consensus regarding the most appropriate methods of sampling for the detection of genital human papillomavirus (HPV) in men. We employed a recently developed collection method involving abrasion and moistened swabbing of the genital skin surface for the detection of HPV in a cohort of 136 university-affiliated males in Hawaii. Genital specimens collected by physicians using this method were compared with self-collected specimens from the same individuals obtained 24 h later. Self-collected specimens yielded a greater proportion of sufficient specimens than physician-collected specimens. HPV detection was comparable in physician- and self-collected specimens; detection was highest in the penile shaft (51.2% and 51.5%, respectively, P = 0.96), followed by the scrotum (41.2% and 46.2%, P = 0.43), the glans/coronal sulcus (31.9% and 33.1%, P = 0.84), and the foreskin (33.3% and 28.6%, P = 0.74). Site-specific agreement in HPV detection between paired physician- and self-collected samples ranged from 67.2% (kappa = 0.34) for the penile shaft to 95.0% (kappa = 0.89) for the foreskin. There was a high degree of concordance in HPV genotypes in HPV-positive pairs. The most common type was HPV type 84, which comprised approximately 15% of the specimens. The emery paper-swab method offers an efficient sampling method for genital HPV DNA detection in men that could be used both within and outside of the clinical setting.

Determination of levodopa methyl ester and its metabolites in rat serum by CZE with amperometric detection

A reliable and reproducible method, capillary zone electrophoresis with amperometric detection (CZE-AD), has been developed for separation and quantification of levodopa methyl ester (LDME) and its biotransformation products levodopa (L-DOPA) and dopamine (DA) in rat serum. A carbon-disk electrode was used as working electrode. The optimum conditions for CZE detection were 50 mmol L(-1) phosphate solution at pH 7.0 as running buffer, 17 kV as separation voltage, 1.0 V (vs Ag/AgCl, 3.0 mol L(-1)) as detection potential, and sample injection for 8 s at 17 kV. The linear ranges were from 2.4 x 10(-2) to 2.2 microg mL(-1) for LDME, 2.9 x 10(-1) to 49.5 microg mL(-1) for L-DOPA, and 1.4 x 10(-2) to 1.5 microg mL(-1) for DA with correlation coefficients of 0.9997, 0.9994, and 0.9999, respectively. The detection limits for LDME, L-DOPA, and DA were 14.6, 98.0, and 9.7 ng mL(-1), respectively. Recoveries were 80.3% for LDME, 93.5% for L-DOPA, and 86.5% for DA. This method was applied to serum samples after intravenous injection of LDME and L-DOPA to rats.

Spontaneous Dissecting Aneurysm of Middle Cerebral Artery: A Case Report with Review of the Literature

We report a case of a dissecting aneurysm of the middle cerebral artery (MCA) and its treatment strategies. A 50-year-old male patient presented with occipital and neck pain for 2 days. CT scan revealed subarachnoid hemorrhage (SAH) in the region of the right sylvian fissure. A left carotid angiogram showed a dissecting aneurysm of the left MCA (M1). He was treated surgically by a pterional trans-sylvian approach. Clipping was done along with additional reinforcement by wrapping to completely obliterate the neck of the aneurysm. On reviewing the literature, we think that dissecting aneurysms seem to be one of the important causes of SAH and cerebral infarction of unverified origin. If an MCA dissecting aneurysm is identified, especially located in the proximal portion, surgical treatment must be considered. These patients merit a close follow-up.

[Evaluation on the cytotoxicity of Gallium alloy by MTT-assay]

OBJECTIVE

To test the cytotoxicity of Gallium alloy, a new mercury-free dental restorative material.

METHODS

L-929 mouse fibroblasts were used to detect the cell relative proliferation rate of Gallium alloy and high-copper amalgam by MTT-assay.

RESULTS

The results indecated that the relative growth rate induced by Gallium alloy was high (93.0% +/- 4.9% 2ds, 102.0% +/- 3.5% 4ds, 107.2% +/- 4.2% 7ds), and the cytotoxicity of Gallium alloy was 0 grade according to the Test Standard of Shanghai Medical Biomaterial, meaning Gallium alloy had no significant cytotoxicity and the relative growth rate of Gallium alloy was higher than that of high-copper amalgam. The high-copper amalgam showed medium cytotoxicity.

CONCLUSION

Gallium alloy has no significant cytotoxicity.

[Cytocompatible evaluation for skin reproducing membrane of medical fibroin]

This study was intended to evaluate the cytocompatibility of skin reproducing membrane of medical fibroin. Cell growth rate test and hemolysis test were conducted to investigate the cytotoxicity and hemolysis reaction for skin reproducing membrane. The results showed there was no obvious cytotoxicity for this kind of membrance. The hemolysis rate was 1.15%. In conclusion, skin reproducing membrane is a material of good cytocompatibility.

[Quality evaluation of indigowoad root and leaf by chemical pattern recognition]

27 samples of indigowoad root and 5 samples of indigowoad leaf from different species and in different habital were collected. The chemical constituents were analyzed by HPLC, and ten original chemical features as a whole obtained. Meanwhile, extrinsic bacteriostasis experiments were carried out for each of the 32 samples. Canonical correlation analysis was applied to the intercorrelation between the chemical and the pharmacologic data, and five chemical features were found to be the effective constituents. In the end, the 32 samples were divided into five classes by the fuzzy clustering technique ISODATA(interachive self-organizing data analysis technique A).

[Molecular cytogenetics study in a case with unbalanced chromosome translocation]

OBJECTIVE

To analyze the chromosome structural aberration in a case of unbalanced chromosome translocation by fluorescence in situ hybridization technique.

METHODS

The 1,18 whole chromosome specific painting probe were used to confirm chromosome abnormality suggested by high resolution G-banding examination.

RESULTS

An unbalanced translocation t(1;18)(q42;q22) was detected in the patient, which caused partial trisomy of 1q42-qter and partial monosomy of 18q22-qter.

CONCLUSION

The identified translocation suggested a potential site for congenital heart disease.

[Study on biocompatibility of skin reproductive membrane]

OBJECTIVE

To study the biocompatibility of skin reproductive membrane.

METHODS

According to ISO's standards, the extractions of the skin reproductive membrane were prepared, and the acute systematic toxicity test, primary skin irritant test, cytotoxicity test, gene expression of type I collagen and fibronectin were detected to evaluate the biocompatibility of skin reproductive membrane.

RESULTS

All of those tests showed negative results.

CONCLUSION

The skin reproductive membrane has excellent biocompatibility in the level of the systematic, cellular and molecular biology.

Nucleotide sequences of the mouse globin beta gene cDNAs in a wild derived new haplotype Hbb(w1)

Haplotypes of the beta-globin gene complex (Hbb) in laboratory mice have been defined as d, p, and s. We previously found a new haplotype w1 in wild mice collected from northwestern China. This study analyzed the nucleotide sequences of b1 and b2-globin gene cDNAs of both the p and w1 haplotypes, in comparison with those of the d haplotype. In Hbb-b1 cDNA, six base substitutions were found between the d and w1 haplotypes and also between p and w1, but none existed between d and p. In Hbb-b2 cDNA, three base substitutions were found between the d and w1 haplotypes and also between d and p, but none between p and w1. This result indicated that the Hbb gene complex of the p haplotype carries b1(d) and b2(w1) genes and is probably a recombinant between d and w1 haplotypes. The hemoglobin containing the W1 phenotype showed oxygen-binding properties identical with those of the hemoglobins containing D and P phenotypes.

[A comparative study on cytocompatibility of medical PVA and intelligent PVA-g-NIPAAm hydrogels]

"Intelligent" Polymers which resonse with large property changes to small physical or chemical stimuli are attracting more and more attention in the field of medical science. One trend in the area is to modify some conventional medical polymers to form intelligent biomaterials. This investigation was designed to evaluate and compare in vitro cytocompatibility of PVA hydrogel, which could be used as a kind of solid support with good biomcompatibility, and PVA-g-NIPAAm, which was produced by irradiation grafting of NIPAAm onto the said PVA hydrogel support. Cytotoxicity test was carried out with a modified Cell Relative Growth Rate test (RGR test). On the day 2, day 4 and day 7, the RGRs of the PVA hydrogel were 82%, 90% and 102% respectively while the RGRs of the PVA-g-NIPAAm were 77%, 86% and 100%. The grades of the cytotoxicity of the PVA and PVA-g-NIPAAm hydrogels were 0, so they had no cytotoxicity as judged by our tests. After 24 hours, cells in direct contact with the two kinds of samples were observed morphologically through the Olympus inverted microscope and had a normal development. The conclusion suggests that irradiation grafting is a good way to modify conventional medical polymers to produce intelligent biomaterials.

Histopathologic changes seen in esophagectomy specimens from the high-risk region of Linxian, China: potential clues to an etiologic exposure?

Esophageal cancer is one of the most fatal cancers worldwide and is characterized by great variation in rates among different populations. Linxian, a county in Henan Province, located in north-central China, has one of the highest rates of esophageal squamous cell carcinoma in the world. Most squamous cell carcinomas in low-risk populations are attributable to alcohol and tobacco consumption, but the causative agents in high-risk populations are less clear. The prevention and treatment of esophageal cancer in high-risk regions, such as Linxian, are limited by our inability to identify these agent(s). During a preliminary histological review, the authors noticed characteristic findings in the arteries, nerves, and lymph nodes of esophagectomy specimens from Linxian and wondered whether these findings might offer clues to the cause of squamous cell carcinoma (eg, polycyclic aromatic hydrocarbon exposure) in the Linxian population. The purpose of this study was to report these previously undescribed histopathologic changes and to compare their presence and severity with those found in esophageal squamous cell carcinomas and adenocarcinomas from a lower-risk population in the United States. Forty esophagectomies were reviewed, including 13 squamous cell carcinomas from Linxian and 21 squamous cell carcinomas and six adenocarcinomas from the United States. The presence and severity of arteriosclerosis and myxoid degeneration of nerves and the presence of anthracosis in periesophageal lymph nodes were recorded. The prevalence and severity of these findings in the three groups of esophagectomies were compared. The esophageal squamous cell carcinomas from Linxian, China, had a higher prevalence of arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes than the squamous cell carcinomas from the United States (Wilcoxon test, P < .04 for all comparisons). There were also significant differences in the prevalence of arteriosclerotic vessels and anthracotic lymph nodes between the esophageal squamous cell carcinomas from Linxian and the adenocarcinomas from the United States. Arteriosclerosis and the myxoid degeneration were significantly more severe in the esophageal squamous cell carcinomas from Linxian than in the esophageal squamous cell carcinomas or adenocarcinomas from the United States (Mantel trend test, P < .006 for all comparisons). Arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes can be seen in association with esophageal squamous cell carcinomas from the high-risk region of Linxian, China. These changes appear to be more prevalent and severe than those seen in association with esophageal squamous cell carcinomas or adenocarcinomas from a low-risk population in the United States. These characteristic changes may be causatively significant and may represent histological evidence of high-level environmental exposure to polycyclic aromatic hydrocarbons.

[Treatment of breast cancer with ipsilateral supraclavicular node metastases]

During 1954-1977, among 2803 cases of breast cancer 99 (3.5%) had ipsilateral supraclavicular node mestastases. The results of treatment are reported, based on follow-up for more than 10 years. According to the treatment modality, the patients were divided into 4 groups: I. surgery with postoperative adjuvant chemotherapy and radiation therapy; II. radiation and chemotherapy; III. chemotherapy; IV. no treatment. In group I, surgical procedures consisted of segmental mastectomy in 6; simple mastectomy in 7; modified radical mastectomy in 16; standard radical mastectomy in 12, and extended radical mastectomy in 3. The over-all five-year survival rate was 9%. It was 18% (8/44) in group I, but only 5% (1/21) in group II. None survived for 5 years in group III and group IV. The results seem to indicate that more aggressive multi-modality treatment of breast cancer with ipsilateral supraclavicular lymph node metastases is indicated to expect better survival.

In vivo imaging of the interior of Tradescantia zebrina leaves by optical cross-correlation interferometry

Using optical correlation interferometry, a novel method for plant sciences, we in imaged in vivo the z-direction, perpendicular to the leaf surface, through Tradescantia zebrina leaves. Non-invasively we determined number of major cell layers, followed the time sequence of decrease in cell z-axis after exposure of tissues to high salt, and observed disruption of cells caused by freezing and thawing.

Inositol 1,4,5-trisphosphate arm of the phosphatidylinositide signal transduction pathway in the rat cerebellum during aging

To determine whether the intracellular calcium-mobilizing second messenger, inositol 1,4,5-trisphosphate (InsP3) and its receptor (InsP3R) display age-dependent coordinate regulation, InsP3 content and [3H]InsP3-binding characteristics were investigated in cerebellar particulate membranes prepared from male Fischer 344 rats at 3, 12 and 25 months of age. Cerebellar InsP3 content was significantly increased in 25-month-old rats compared with 3-month-old animals. Cerebellar InsP3R densities were significantly reduced at 12 and 25 months of age but InsP3-binding affinity was significantly decreased only in the 25-month-old animals. The present data strongly suggest that modulation of the phosphoinositide second messenger system may contribute to impaired neuronal responsiveness associated with the aging process in the cerebellum.