[Efficacy analysis of laparoscopic sleeve gastrectomy in morbidly obese patients aged 10-21 years]

Objective: To investigate the efficacy of laparoscopic sleeve gastrectomy (LSG) in morbidly obese patients aged 10 to 21 years. Methods: We conducted a retrospective analysis of clinical data from 89 out of 200 patients who underwent LSG at the Gastrointestinal Surgery/Weight Loss Center of the First Affiliated Hospital of Jinan University between January 2015 and December 2020. The primary outcome measures were the completion rate of LSG, the incidence of perioperative complications, and weight-related indicators 3, 6, 12, and ≥24 months postoperatively. Additionally, we compared glucose metabolism, lipid metabolism, vitamin levels, liver function, and other relevant biochemical variables before and after surgery. Normally distributed continuous data are presented as x±s. Because the numbers of patients at each follow-up time point were not identical with the number of patients in the study cohort preoperatively, independent sample t-tests were used for intergroup comparisons. Non-normally distributed continuous data are presented as M(Q1, Q3), and Mann-Whitney U tests were used for intergroup comparisons. Results: Among the 89 patients, 35 were male (39.3%), the mean age was (18±2) years, and mean body mass index (BMI) 38.5±4.8 kg/m²; 37 of the patients having a BMI greater than 40 kg/m². Additionally, 63 patients (70.8%) had fatty livers, 34 (38.2%) hyperuricemia, 31(34.8%) sleep apnea syndrome, 20 (22.4%) gastroesophageal reflux, eight (8.9%) type 2 diabetes, and two (2.2%) hypertension. All 89 patients underwent LSG surgery successfully, with no conversions to open surgery. During the perioperative period, there were no cases of major bleeding, gastric leakage, or infections. Notable postoperative symptoms included nausea, vomiting, and pain, most of which improved by the second postoperative day. BMI values 3, 6, and 12 months postoperatively had decreased to 31.5±5.8 kg/m², 28.6±4.3 kg/m², and 26.3±4.4 kg/m², respectively. All of these BMI values differed significantly from preoperative values (all P<0.05). At 12 and ≥24 months postoperatively, the percentages of total weight loss were (31.3±9.3)% and (33.1±10.5)%, respectively, both differing significantly from 3 months postoperatively (20.5±5.1)% (all P<0.05). The percentages of excess weight loss at 12 and ≥24 months postoperatively were 91% (70%, 113%) and 95% (74%, 118%) , respectively, both differing significantly from the percentage of total weight loss 3 months postoperatively (56% [45%, 72%]) (both P<0.05). Alanine transaminase and aspartate transaminase serum concentrations decreased from preoperative values of 44.4 (25.5, 100.5) U/L and 29.0 (9.5, 48.0) U/L to 14.0 (10.8, 18.3) U/L and 13.0 (10.5, 17.3) U/L, respectively, ≥24 months postoperatively. Hemoglobin A1c decreased from 5.6 (5.3, 5.8)% preoperatively to ≥24 months postoperatively 5.3 (5.0, 5.4)%. High-density lipoprotein increased from 1.0 (0.9, 1.2) mmol/L preoperatively to 1.4 (1.1, 1.6) mmol/L ≥24 months postoperatively. Vitamin B12 decreased from 350.0 (256.8, 441.3) μg/L preoperative to 230.3(195.4, 263.9) μg/L ≥24 months postoperatively. All differed significantly from preoperative values (all P<0.05). Conclusion: LSG has favorable efficacy in morbidly obese patients aged 10 to 21 years. However, further confirmation is required through long-term, multicenter, randomized, controlled trials.

Decreased cyclic-AMP caused by ATP contributes to fosfomycin heteroresistance in avian Escherichia coli

BACKGROUND

Fosfomycin is an important broad-spectrum bactericidal antibiotic to treat multidrug-resistant bacteria infections. It is generally accepted that heteroresistant bacteria are an intermediate stage in the formation of drug resistance, but there are few studies on the formation mechanism underlying fosfomycin heteroresistance (FHR).

OBJECTIVES

To reveal the characteristics and formation mechanisms of FHR in Escherichia coli isolates obtained from chickens.

METHODS

We identified the FHR according to the population analysis profile (PAP) test and in vitro time-kill assay. Growth curves for FHR E. coli and their subpopulations were measured. Also, the subpopulations were repeatedly cultured in fosfomycin-free medium for 5-20 overnight incubation periods. The formation mechanisms of FHR in E. coli isolates were identified through accumulation assay, carbohydrate utilization testing, real-time relative quantitative PCR analysis, DNA sequencing, transcriptomic analysis, intracellular ATP and cAMP-level assessment.

RESULTS

Four of six E. coli strains were confirmed to show FHR, with a total of six subpopulations. The subpopulations restored phenotypic susceptibilities to fosfomycin within 5-20 overnight incubation sessions, but four of six subpopulations still maintained FHR characteristics. Differing from their parental isolates, the uptake of fosfomycin in the subpopulations through GlpT was reduced remarkably. Further studies identified that the low expression of glpT was due to the decrease of intracellular cAMP levels in the subpopulations, which was caused by the decreased ATP levels in cells.

CONCLUSIONS

Our findings revealed the formation mechanism of E. coli isolates showing FHR obtained from chicken in China and characterized the dynamic change traits in vitro of the subpopulations.

[Occurrence of gastric cancer after laparoscopic Roux-en-Y gastric bypass: a systematic review]

Laparoscopic Roux-en-Y gastric bypass (RYGB) is an important obesity surgery. The risk of remnant gastric cancer after RYGB for obesity is gaining growing attention from bariatric surgeons and patients with obesity. This systematic review included articles from major databases internationally and domestically that specifically described the remnant gastric cancer after RYGB intervention, a total of 21 cases was subsequently analyzed. The average median time from post-operative RYGB to diagnosis of gastric cancer was 11 years (1-28 years), the duration of gastric cancer symptoms lasted 7 days to 6 years, abdominal pain is the most common (71.4%), especially in the upper abdomen (33.3%), followed by nausea and vomiting (33.3%), over-weight loss (33.3%), and abdominal bloating (28.6%), etc. Neoplasm location was reported to occur in the antrum or the pre-pyloric region (71.4%), with adenocarcinoma being the most common tumor histology observed (71.4%), tumor stage III-IV as the most diagnosed, 38.1% of tumor were deemed to be unresectable, 52.4% of the patients performed subtotal gastrectomy and lymphadenectomy. In addition, a global article investigating the occurrence of esophageal gastric cancer after RYGB in 64 cases revealed the common preoperative medical history include smoking habits (37.5%), alcohol issues (14.0%), GERD (86.0%), presence with Barret esophagus (10.9%), patients that has other malignant tumor medical history (6.3%), first-degree relatives (6.3%), or other family members with gastric esophagus cancer family history. Although the incidence of gastric cancer after RYGB is rare, the increasing prevalence of gastric cancer development is one of great concern. A rise in clinical cases of patients treated with RYGB presents a target for future studies. Risk of gastric cancer after RYGB should be evaluated and considered in high-risk cases.

Performance of two rapid point of care SARS-COV-2 antibody assays against laboratory-based automated chemiluminescent immunoassays for SARS-COV-2 IG-G, IG-M and total antibodies

Introduction

We evaluated two SARS-CoV-2 antibody point-of-care tests (POCTs) (Abbott Panbio COVID-19 IgG/IgM and Roche SARS-CoV-2 Rapid Antibody tests) and compared the results to their respective chemiluminescent immunoassays (CLIAs) (Abbott Architect IgM, Architect IgG, Roche Cobas total antibody assays).

Method

200 pre-pandemic sera and 48 samples positive for various conditions (18 viral hepatitis, 18 dengue, 11 ANA and 1 dsDNA) were used as controls and to assess for cross-reactivity. Anonymised residual leftover sera positive for SARS-CoV-2 on RT-PCR were recruited as cases (n ​= ​133). The sensitivity/specificity/cross-reactivity/positive predictive value (PPV)/negative predictive value (NPV) of the POCTs were assessed. Concordance between the POCTs and chemiluminescent immunoassays (CLIAs) were analysed.

Results

Abbott/Roche POCT specificity was 98.7%/100% (95% CI 96.5–99.8/98.5–100) and sensitivity was 97.2%/97.2% (95% CI 85.5–99.9/85.5–99.9) in cases ≥14 days post-first positive RT-PCR (POS), PPV was 68.7%/100% (95% CI 41.3–87.2/94.7–100.0), and NPV was 97.4%/97.6% (95% CI 97.0–97.8/97.2–98.0). In cases ≥14 days POS, concordance of Abbott/Roche POCT and CLIAs was 97.2%/100% (35/36 and 36/36 results). The sensitivity of individual IgM-band results on both POCTs did not increase >95% even after 14 days POS (Abbott 2.78%, Roche 44.4%).

Conclusion

Both POCTs have good specificity, little cross-reactivity with other antibodies, and sensitivity >95% when used in subjects ≥14 days POS. Analysis of individual POCT IgG/IgM-bands did not provide any additional information. POCTs can substitute for CLIAs in cases ≥14 days POS. In low prevalence areas, POCTs would be especially useful when combined with antigen testing in an orthogonal format to increase the PPV of COVID-19 results.

•

The POCT IgM-band is negative in most cases of COVID-19.

•

There is little utility in examining the IgG-IgM bands individually.

•

Like CLIAs, the sensitivity of the POCTs is >95% 14 days after RT-PCR positivity.

•

Combining POCTs with another test orthogonally improves the PPV.

[The clinical application of blood routine and liver and kidney function test in COVID-19 disease prediction]

Objective: To explore the clinical application value of routine indicators such as blood routine and liver and kidney function in auxiliary diagnosis and prognosis of COVID-19 patients. Methods: SNK-q and other methods were used to retrospectively analyzed the differences of blood routine test, liver and kidney function and other inflammatory indexes of 30 patients with covid-19, 29 patients with other viral pneumonia, 35 patients with influenza A/B and 25 healthy persons from January 28 to February 14, 2020 in Xiangya Hospital of Central South University. Results: The neutrophils count increased gradually in COVID-19 group, influenza A/B group and other types of viral pneumonia group, and the difference between COVID-19 group and other viral pneumonia groups was statistically significant(H=-19.064,P<0.05); The lymphocyte count decreased gradually in the control group, influenza A/B group, other viral pneumonia group and COVID-19 group. In addition, DB, UA and GLU were also different among groups. Subgroup analysis showed that there were statistically significant differences in N(F=9.581,t=-0.152,P<0.05), N%(F=5.723,t=-0.600, P<0.05), NLR(F=4.773, t=-1.161, P<0.05), PCT(F=17.464, t=-1.477, P<0.05)and CRP(F=7.656, t=-1.973, P<0.05) between patients with lung involvement +-++ and patients with lung involvement +++-++++. There were statistically significant differences in NLR(F=63.931, t=-2.815, P<0.01), AST(F=15.704, t=-1.930, P<0.01), ALT(F=35.551, t=-2.199, P<0.01), LDH(F=7.715, t=-2.703, P<0.05) and GLU(F=6.306, t=-5.116, P<0.05) between the light+common subgroup and the heavy+critical subgroup of COVID-19 clinical classification. Correlation analysis showed that clinical stage and imaging credit period were significantly correlated with NLR (r=0.406, P=0.026; r=0.397, P=0.030), ALT (r=0.403, P=0.049; r=0.418, P=0.047), LDH (r=0.543, P<0.01; r=0.643, P<0.01) and GLU(r=0.750, P<0.01; r=0.471, P=0.042). A total of 5 principal components were extracted from all the included indicators, and the comprehensive information extraction rate was 82.86%. Indicators of a large load included Ur, PCT and CRP in PC1; ALT, AST and GLU in PC2; N%, L%, L and NLR in PC3. It indicated that the indicators of acute infection, liver function and blood routine had certein warning effect on disease surveillance. The results of ROC curve analysis showed that the combined detection of N+TB+Urea was the best practice to distinguish COVID-19 and other viral pneumonia, while the combined detection of N+L+UA was the most effective solution to make a distinction between COVID-19 and influenza A/B patients. In the aspect of disease evaluation, NL+LDH+GLU+ALT combined detection represent the best diagnostic performance to distinguish the clinical stage of light+common type and heavy+critical type, achieving the AUC (ROC) to 0.904, with the sensitivity 75% and the specificity 100% at the cut-off value of 0.477. Conclusion: In addition to etiology and imaging examination, doctors can also improve the routine laboratory tests such as blood routine test, liver and kidney function to assist diagnosis and disease prediction of patients with respiratory tract infection.

Performance of an automated chemiluminescence SARS-CoV-2 IG-G assay

INTRODUCTION

We describe our evaluation of the Abbott SARS-CoV-2 IgG assay on the Architect immunoassay analyser.

METHODS

We assessed assay precision, sensitivity, specificity, positive/negative predictive values (PPV/NPV), cross-reactivity (influenza/dengue/hepatitis B and C/rheumatoid factor/anti-nuclear/double-stranded DNA/syphilis) and sample throughput in samples from real-time polymerase chain reaction (RT-PCR) positive patients/healthcare workers (HCWs)/pre-pandemic samples. We compared the cut-off indexes (COIs) between all control samples (HCWs and pre-pandemic) to generate an optimised COI limit for reactivity.

RESULTS

The assay specificity was 99.8% (n = 980) and sensitivity was 45.9-96.7% (n = 279). When tested ≥ 14 days post-positive RT-PCR (POS), the PPV/NPV was 96.4%/99.8%. The difference between the COIs of HCWs/pre-pandemic samples was small (0.01, p < 0.0001). There was minimal cross-reactivity with other antibodies. A lower COI limit for reactivity (≥0.55, using the 99th percentile COI of our controls and ROC analysis) improved diagnostic sensitivity, especially at 0-6 days POS (45.9-55.8%), with a small decrease in specificity (98.9%). The assay throughput was 100 samples in 70 min.

CONCLUSION

The Abbott SARS-CoV-2 IgG assay shows excellent performance in patients ≥ 14 days POS. The difference between the COIs of HCWs and pre-pandemic samples was numerically small. A lower COI limit improves assay sensitivity with a slight decrease in specificity.

Thoughts on the effects of moxa smoke in the epidemic prevention

Through summarizing and analyzing the modern mechanism researches and controversial questions of moxibustion fumigation in the epidemic prevention, the thoughts on tackling the critical points are proposed in the paper, such as the recognition of moxa smoke in traditional Chinese medicine (TCM), the mechanism of moxa smoke in air disinfection and the characteristics of clinical application of moxa smoke so as to provide the references to the prevention and control of COVID-19 in TCM.

[Effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury]

Objective: To investigate the effect of low dose erythromycin on the proliferation of granulation tissue after tracheal injury. Methods: Forty-two rabbits were randomly divided into 7 groups (n=6 each), group A (saline control group), group B (penicillin group), group C (low dose erythromycin group), group D (low dose erythromycin and penicillin group), group E (budesonide group), group F (low dose erythromycin and budesonide group), group G (low dose erythromycin, penicillin and budesonide group). All rabbits received tracheotomy, and the tracheal mucosa was scraped with a nylon brush 20 times for tracheal stenosis model. Rabbits were treated with corresponding drugs from a week before operation to 9 days after operation. The serum concentrations of transforming growth factor - beta 1 (TGF-β(1)), vascular endothelial growth factor (VEGF), interleukin (IL) -6, IL-8 were determined and the tracheal specimens were harvested for measuring degree of stenosis on the 10th day after operation. Results: Serum concentrations of TGF-β(1) in group A, B, C, D, E, F and G were (17.6±1.3), (18.2±3.1), (13.0±1.1), (14.0±1.0), (21.0±6.1), (13.6± 3.5), (8.2±1.3) ng/L; VEGF were (88.1±4.1), (85.8±4.3), (58.1±6.3), (56.5±2.4), (87.8±2.8), (57.0±3.7), (34.3±6.7) ng/L; IL-6 were (67.8±4.0), (66.1±3.5), (54.1±4.8), (52.1±3.2), (64.6±4.9), (49.4±4.2), (35.9±3.7) ng/L; IL-8 were (112.8±5.2), (116.6±4.1), (88.0±6.2), (85.5±3.5), (114.4±4.6), (82.6±3.8), (55.9±6.0) ng/L, respectively. The serum concentrations of TGF-β(1), VEGF, IL-6 and IL-8 in group C, D, F and G were significantly lower than those in group A, B and E (all P<0.05). Compared with the other groups, the serum concentrations in group G were the lowest (all P<0.05). All 42 rabbits had tracheal stenosis with different degrees of proliferation of granulation tissue. The degree of tracheal stenosis in Group A, B, C, D, E, F and G were (53.3±4.4)%, (48.2±5.0)%, (24.3±4.4)%, (29.5±3.2)%, (47.8±6.5)%, (27.9±3.1)%, (15.6±2.0)%, respectively. The degree of tracheal stenosis in group C, D, F and G was significantly lower than that in group A, B and E, which had statistical differences (all P<0.05). Compared with the other groups, the degree of tracheal stenosis in group G was the lowest (all P<0.05). Conclusions: Low dose of erythromycin can effectively inhibit the proliferation of granulation tissue after tracheal injury in rabbits. And it has better effectiveness when combined with other antibiotics and hormone.

[The research on the application of uncut Roux-en-Y esophagojejunostomy in the digestive reconstruction after totally laparoscopic total gastrectomy]

Objective: To evaluate the safety and flexibility of uncut Roux-en-Y esophagojejunostomy in totally laparoscopic total gastrectomy (TLTG). Methods: Between July 2016 to November 2016, 15 patients received totally laparoscopic total gastrectomy plus uncut Roux-en-Y esophagojejunostomy in the Sir Run Run Shaw hospital. Clinical data of those patients, including operative indexes, post-operative indexes and fellow-up data, were analyzed respectively. Results: A total of 15 patients were enrolled in this study, ten were corpus carcinoma and five were esophagogastric junction carcinoma. The total operative time and anastomosis time was (25.0±4.3) min and (25.0±4.3) min, the blood loss during operation was (133.3±121.2) ml. All the operations were performed successfully, and no one was transferred to open surgery. All the patients were encouraged to off-bed activity at first day after surgery. The first time to flatus, the first time to liquid food intake and the length of stay in hospital were (4.1±0.8) days, (5.1±0.9) days and (9.3±1.6) days, respectively. The pathological staging of these patients was stage Ⅰb in 1 case, stage Ⅱa in 3 cases, stageⅡb in 2 cases, stage Ⅲb in 3 cases, stage Ⅲc in 6 cases. The lymph node harvest was (36.0±12.3). Cutting margins in all patients were negative. Pulmonary infection occurred in one patient postoperatively and recovered after antibiotic treatment. No death and severe complication was found. Liver metastasis occurred in one patient eight months after operation. One patient was found recurrence in anastomotic site. No Roux-en-Y stasis syndrome was found. Conclusions: Uncut Roux-en-Y esophagojejunostomy in TLTG is safe and flexible.

[Effect of febuxostat on epithelial-to-mesenchymal transition of kidney tubules, serum interleukin-6 and transforming growth factor β(1) in hyperuricemic rats]

Objective: To observe the effect of febuxostat on epithelial-to-mesenchymal transition (EMT) of kidney tubules and the levels of serum IL-6 nad transforming growth factor (TGF)β(1) in hyperuricemic rats. Methods: Forty male SD rats were divided into 4 groups: normal control group (NC group), oteracil potassium group (OP group), oteracil potassium with febuxostat group (OF group) and oteracil potassium with benzbromarone group (OB group). Each group had 10 rats and balanced in body weights. To induce hyperuricemia, rats were given oteracil potassium by gastric gavage once a day for eight weeks. Rats in OF group and OB group were given either febuxostat or benbromarone starting with oteracil potassium, and rats in NC group was given saline only. Blood samples were taken before, and at the end of 4 and 8 weeks of the treatments and serum uric acid, creatinine, blood usea nitrogen(BUN), IL-6 and TGFβ(1) contents were measured at each time point. Renal pathological changes were observed via HE and Masson staining, and the expression of α-SMA and E-cadherin were detected by immunohistochemistry. Results: Compared with those in NC group, the levels of serum uric acid, creatinine, BUN, IL-6 and TGFβ(1) in the another three groups were increased significantly (all P<0.01). However, the IL-6 and TGFβ(1) contents in OF group were much lower than those in OP group (P<0.01). HE and Masson staining showed that OF group had less damage and tubulointerstitial fibrosis than OP group and OB group (P<0.01). Moreover, the expression of α-SMA was significantly down-regulated (P<0.01) and that of E-cadherin was significantly up-regulated in OF group compared with those in OP group. Conclusion: Febuxostat treatment significantly inhibited EMT and reduced the levels of IL-6 and TGFβ(1) in hyperuricemia rats.

[Risk factors analysis of reversible posterior leukoencephalopathy syndrome in pre-eclampsia or eclampsia gravida]

Objective: To investigate the risk factors of reversible posterior leukoencephalopathy syndrome (RPLS) in pre-eclampsia or eclampsia gravida. Methods: This study was conducted in the Third Affiliated Hospital of Guangzhou Medical University between January 2013 and March 2016. A total of 100 patients who had no severe neurological diseases and were diagnosed pre-eclampsia or eclampsia, and underwent brain MRI were collected retrospectively. They were divided into 2 groups according to the MRI results, the RPLS group (n=49) and the non-RPLS group (n=51). The medical history, clinical symptoms and the results of laboratory examination were analyzed by the logistic regression, in order to explore the risk factors. Results: In single factor analysis, HELLP syndrome, pregnancy associated with other diseases, poor prenatal care, grade 3 hypertension, elevated systolic blood pressure or diastolic blood pressure, elevated WBC, aspartate transaminase (AST), alanine aminotransferase (ALT), uric acid (UA) and lactate dehydrogenase (LDH), decreased platelet (PLT), headache, visual changes, seizures and conscious disturbance were more frequent in the RPLS group than those in the non-RPLS group (all P<0.05). According to the multivariate logistic regression analysis, the elevated WBC (OR=1.291, 95% CI: 1.058-1.575, P=0.012), UA (OR=1.008, 95% CI: 1.001-1.016, P=0.032) and headache (OR=18.260, 95% CI: 3.562-93.607, P=0.000) were the independent risk factors. Conclusions: Maternal history, clinical symptoms and some laboratory examinations might help in the early diagnosis of RPLS in pre-eclampsia or eclampsia gravida. Headache, the elevation of WBC and UA were the most significant factors.

[Influence of Electroacupuncture Intervention on Glutamic Acid and Ca2+ Contents and Expression of NMDA Receptor Protein in Hippocampus in Vascular Dementia Rats]

OBJECTIVE

To observe the influence of electroacupuncture (EA) intervention on hippocampal glutamate (Glu) and Ca²⁺ contents, and expression of Glu-N-methyl-D-aspartic acid receptor(NMDAR) and the learning-memory ability in vascular dementia (VD) rats, so as to reveal its mechanisms underlying improvement of VD.

METHODS

SD rats were rando-mized into sham operation (sham) group (n=9), model group (n=11) and EA groups (n=10). The VD model was established by repeated bilateral common carotid arteries occlusion and reperfusion plus intraperitoneal injection of sodium nitroprusside. EA (2 Hz, 2 mA) was applied to "Baihui" (GV 20)-"Housanli" (ST 36) and "Geshu" (BL 17)-"Dazhui" (GV 14) for 10 min, once a day for 15 consecutive days. The neurological function was assessed by using stroke index (0-10 points) and neurological deficit scaling(0-10 points). The learning-memory ability was evaluated by using step-down tests. The contents of Glu and Ca²⁺ in the right hippocampal tissue were determined by using aspectrophotometer and the expression of NMDAR protein in the right hippocampus was detected by immunoblotting.

RESULTS

Compared with the sham group, the stroke index and neurological deficit scores, and the reaction latency and the error times of step-down tests, as well as the contents of Glu and Ca²⁺ and the expression level of NMDAR in the right hippocampus were significantly increased in the model group (P<0.05, P<0.01), while the step-through latency was considerably decreased (P<0.01), suggesting a neurological disorder and a cognitive decline. After EA intervention, the reaction latency and error times of step-down tests, the contents of Glu and Ca²⁺ and the expression level of NMDAR in the right hippocampus were significantly down-regulated, and the step-through latency was notably increased in comparison with the model group (P<0.01).

CONCLUSIONS

EA intervention is able to improve the cognitive ability of VD rats, which may be associated with its effects in reducing the excitatory neurotoxicity of hippocampal Glu-NMDAR and lowering cellular Ca²⁺ load to resist neuronal injury.

[Relationship and interaction between folate and expression of methyl-CpG-binding protein 2 in cervical cancerization]

OBJECTIVE

To explore the interaction between folate and the expression of methyl-CpG-binding protein 2(MeCP2)in cervical cancerization.

METHODS

Forty one patients diagnosed with cervical squamous cell carcinoma(SCC), 71 patients diagnosed with cervical intraepithelial neoplasm(CIN1, n=34; CIN2 +, n=37)and 61 women with normal cervix(NC)were recruited in this study. Microbiological assay was conducted to detect the levels of serum folate and RBC folate, Western blot assay and real-time PCR were performed to detect the expression levels of MeCP2 protein and mRNA, respectively. The data were analyzed by Kruskal-Wallis H test, χ(2) test, trend χ(2) test and Spearman correlation with SPSS statistical software(version 20.0), and the interaction were evaluated by using generalized multifactor dimensionality reduction(GMDR)model.

RESULTS

The levels of serum folate(H=44.71, P<0.001; trend χ(2)=24.48, P<0.001)and RBC folate(H=5.28, P<0.001; trend χ(2)=3.83, P<0.05)decreased gradually along with the severity of cervical lesions. There was a positive correlation between serum folate level and RBC folate level(r=0.270, P< 0.001). The expression levels of MeCP2 protein(H=33.72, P<0.001; trend χ(2)=14.74, P<0.001)and mRNA(H=19.50, P<0.001; trend χ(2)=10.74, P<0.001)increased gradually along with the severity of cervical lesions. There were negative correlation between folate level and the expression level of MeCP2 protein(serum folate: r=-0.226, P=0.003; RBC folate: r=-0.164, P=0.004). Moreover, the results by GMDR model revealed there were interaction among serum folate deficiency, RBC folate deficiency, MeCP2 protein high expression and MeCP2 mRNA high expression in SCC and CIN2 + patients.

CONCLUSION

Folate deficiency and high expression of MeCP2 gene might increase the risk of cervical cancer and its precancerous lesions through interaction among serum folate deficiency, RBC folate deficiency, MeCP2 protein high expression and mRNA high expression in the progression of cervical cancerization.

Verification and evaluation of grain QTLs using RILs from TD70 x Kasalath in rice

Grain size is an important trait that directly influences the yield of rice. Validation and evaluation of grain genes is important in rice genetic studies and for breeding. In a population of 240 recombinant inbred lines (RILs) derived from a cross between an extra-large grain japonica variety TD70 and a small grain indica variety Kasalath, we mapped 19 QTLs controlling grain traits. These QTLs included six cloned grain genes, namely, GW2, GS3, qSW5, qGL3, GS5, and GW8. All of the alleles with the optimal effects on grain size came from TD70, the variety with extra-large grains. To verify these gene loci, we cloned and sequenced GW2, GS3, GW5 (qSW5), qGL3, GS5, GW8, and TGW6 in TD70 and Kasalath, and found several functional polymorphisms in the sequences of the genes. New functional markers for the cloned genes were designed to identify parents and RILs. The contributions of these polymorphisms to the improvement in rice grain size traits were evaluated. Our results indicate that at least six functional polymorphisms have additive effects on grain shape and that one non-functional polymorphism in TGW6 affects grain shape in TD70. The newly designed markers will be useful in further studies to identify functional grain genes. Our findings provide insight into the control of grain size in rice, and they will be of value for improving rice grain yield.

[Effect of electroacupuncture intervention at different time-points of post-modeling on hippocampal monoamine neurotransmitter levels in mice with vascular dementia]

OBJECTIVE

To observe the effect of electrocupuncture (EA) intervention at different time-points of post-modeling on behavior and hippocampal monoamine neurotransmitter noradrenalin (NE), dopamine (DA) and 5-hydroxytrypamine (5-HT) contents in vascular dementia (VD) mice, so as to study its mechanism underlying improvement of VD.

METHODS

A total of 60 Kunming mice were randomized into sham-operation control (n = 20), VD model (n = 20), EA-day (D)-1 (EA treatment was given from the 1st day on after modeling, n = 10), EA-D-3 (EA was given from the 3rd day on after modeling, n = 10) groups. VD model was established by occlusion of the bilateral cervical common arteries and reperfusion. EA (2 Hz/80 Hz) was applied to "Baihui" (GV 20), "Dazhui" (GV 14),"Zusanli" (ST 36) and "Geshu"(BL 17) for 10 min, once daily for 15 days. Hippocampal NE, DA and 5-HT contents were assayed by fluorospectrophotometry. The mouse's learning-memory ability was assessed by step-down tests.

RESULTS

In comparison with the sham-operation control group, the learning-memory ability (marked increase of reaction time and error times, decrease of step-down latency) was apparently lowered in the model group (P < 0.01). The hippocampal NE, DA and 5-HT contents were significantly lower in the model group than in the sham-operation group (P < 0.01). Compared with the model group, the mice's learning-memory ability (marked decrease of reaction time and error times, increase of step-down latency) was significantly increased in EA intervention groups (P < 0.01), and hippocampal NE, DA and 5-HT levels were significantly increased (P < 0.01), and the effect of EA-D-3 group was obviously better than that of the EA-D-1 group (P < 0.05, P < 0.01).

CONCLUSION

EA can improve the VD mice's learning-memory ability, which is closely related to its effects in up-regulating hippocampal NE, DA and 5-HT contents, and the effect of later EA intervention after modeling is better.

[Effect of mild moxibustion on macrophage number and collagen expression of raw surface tissue in chronic refractory skin ulcer rats]

OBJECTIVE

To observe the effect of mild moxibustion on the number of macrophages and contents of collagen I and III in the raw surface tissue in chronic skin ulcer rats so as to study its mechanism underlying promoting scar formation.

METHODS

Eighty male SD rats were randomly divided into normal (n = 8), model (n = 24), TDP (n = 24) and moxibustion (n = 24) groups. Chronic refractory skin ulcer was established by making an open wound at the back and local intramuscular injection of hydrocortisone sodium succinate. For rats of the TDP and moxibustion groups, TDP irradiation or mild moxibustion was applied to the raw surface, bilateral "Shenshu" (BL 23) and "Zusanli" (ST 36) for 15 min, once daily for 7, 10 and 14 days, respectively. The number of macrophages in the raw surface tissue was counted under light microscope after H. E. staining and col- lagen I and III expressions of the raw surface tissue were detected by immunohistochemistry.

RESULTS

In comparison with the normal group, the numbers of macrophages in the raw surface tissue were increased significantly in the model group on day 7, 10 and 14 (P < 0.05); while compared with the model group, the numbers of macrophages were increased further obviously in the moxibustion group on day 7 and 10 and in the TDP group on day 10 after the treatment (P < 0.05). Compared with the model group, the numbers of macrophages in both TDP and moxibustion groups were down-regulated obviously (P < 0. 05). In regard to collagen I and III expression of the raw surface tissue, compared with the normal group, the collagen I protein expression level was down-regulated markedly in the model group on the 7th day (P < 0.01); whereas in comparison with the model group, the expression levels of collagen I and III were increased considerably in the TDP and moxibustion groups on day 7 and 14 after the treatment (P < 0.05, P < 0.01). The ratios of collagen I/III expression were remarkably higher in the model group than in the normal group on day 7 and 14 (P < 0.05), and significantly lower in the TDP group on day 7 and 14 and in the moxibustion group on day 14 than in the model group (P < 0.05, P < 0.01). The effects of moxibustion were obviously superior to those of TDP in up-regulating macrophage number on day 10, up-regulating collagen I and III expressions on day 14, and down-regulating macrophage number on day 14 after the treatment (P < 0.05, P < 0.01). No significant differences were found between the TDP and moxibustion groups in up-regulating macrophage number, and collagen I and III protein expressions, and in down-regulating the ratios of collagen I/III expression on day 7 after the treatment (P > 0.05).

CONCLUSION

Mild moxibustion can regulate the number of macrophages and strengthen the expression of collagen proteins in the raw surface tissue in the chronic skin ulcer rats, which may contribute to its effect in promoting wound healing and reducing scar formation.

[Effect of electroacupuncture on lipid metabolism in male and female obesity rats]

OBJECTIVE

To investigate the influence of electroacupuncture (EA) on lipid metabolism in both sexes of obesity model rats.

METHODS

A total of 30 male and 30 female SD rats were randomized into normal control, model and EA groups respectively, with 10 rats in each group. EA (2 Hz, 1-2 mA) was applied to the ipsilateral "Zusanli" (ST 36)-"Sanyin-jiao"(SP 6) and bilateral "Fenglong" (ST 40) for 30 min, once daily for 28 days. In addition,"Quchi" (LI 11),"Zhongwan" (CV 12) and "Guanyuan" (CV 4) were punctured with filiform needles and stimulated by manipulating the needle for 1 min, separately. Obesity model was duplicated by subcutaneous injection of 15% glutamic sodium (0.2 mL/10 g) once daily for 5 days and by feeding the animal with high fat forage for 36 days. Lee's index was calculated, and plasma triglyeride (TG) concentration detected by glycerol-phosphoric acid oxidase-peroxydase method, total cholesterol (TC) detected by cholesterol oxidase method, and plasma low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) contents were assayed by one-step method, respectively.

RESULTS

In both male and female rats, compared to their own normal groups, the Lee's index, plasma TG, TC and LDL-C contents were increased significantly and plasma HDL-C contents decreased obviously in the model groups (P<0.01), while compared to their own model groups, the Lee's index, plasma TG, TC and LDL-C levels in the EA groups were down-regulated considerably and plasma HDL-C contents up-regulated remarkably after the treatment (P<0.01, P<0.05). The efficacies of the EA intervention were obviously better in reducing Lee's index for male rats, and in down-regulating plasma TG and TC contents in female rats (P<0.05). No significant differences were found between male and female rats in EA intervention for plasma LDL-C and HDL-C levels.

CONCLUSION

EA intervention can effectively regulate obesity rats' Lee's index and plasma TG, TC, LDL-C and HDL-C levels. The effects are different in male and female rats.

Placebo-controlled trial of transdermal estrogen therapy alone in postmenopausal women: effects on arterial compliance and endothelial function

BACKGROUND

The cardiovascular effects of hormone replacement therapy (HRT) are controversial. Improvement in vascular function, potentially mediated, at least in part, via improvements in lipid profiles, is a proposed mechanism of estrogen action; however, there are few controlled human trials. We have studied the effects of HRT, independent of changes in lipid profile, with transdermal estrogen therapy, focusing on blood pressure, lipid profiles and vascular function, encompassing both biomechanical arterial properties (systemic arterial compliance and pulse wave velocity) and endothelial function (flow-mediated vasodilatation).

METHODS

In this 2-year, double-blind, placebo-controlled, cross-over study, 34 healthy postmenopausal women were randomized to transdermal estrogen alone (Menorest, 50 micrograms) or placebo. After withdrawals, 25 women completed measurements at baseline, 6 weeks, 6 months and 12 months during both treatment phases.

RESULTS

Transdermal estrogen did not improve blood pressure, lipid profiles or arterial function, compared with placebo.

CONCLUSION

From this randomized, controlled trial, it appears that transdermal estrogen alone, in healthy postmenopausal women, does not improve lipid profiles or a spectrum of indices of arterial function, compared with placebo. These results would suggest that there might not be a beneficial effect of transdermal HRT on the vasculature in postmenopausal women.

Gender differences in the timing of arterial wave reflection beyond differences in body height

OBJECTIVES

The timing of arterial wave reflection affects the shape of the arterial waveform and thus is a major determinant of pulse pressure. This study assessed differences in wave reflection between genders beyond the effect of body height.

METHODS

From 1123 elderly (aged 71 +/- 5 years) currently untreated hypertensives, we selected 104 pairs of men and women with identical body height (average 164 +/- 4 cm). All subjects underwent echocardiography, including measurement of aortic arch expansion, automated blood pressure measurements, measurement of ascending aortic blood flow and simultaneous carotid artery tonometry.

RESULTS

Women had higher pulse (80 +/- 17 versus 74 +/- 17 mmHg, P < 0.05) and lower diastolic pressure (79 +/- 11 versus 82 +/- 10 mmHg, P < 0.05). Whilst heart rate was similar, women had a longer time to the systolic peak (210 +/- 28 versus 199 +/- 34 ms, P < 0.01) and a longer ejection time (304 +/- 21 versus 299 +/- 25 ms, P < 0.001). Wave reflection occurred earlier in women (time between maxima 116 +/- 55 versus 132 +/- 47 ms, P < 0.05) and augmentation index was higher (36 +/- 11 versus 28 +/- 12%, P < 0.001). Aortic diameter was smaller in women and the aortic arch was stiffer (median Ep 386 versus 302 kN/m2, P < 0.05). Hence, systemic arterial compliance was less in women (0.8 +/- 0.2 versus 1.0 +/- 0.3 ml/mmHg).

CONCLUSIONS

We conclude that elderly hypertensive men and women have a different timing of both left ventricular ejection and arterial wave reflection when both genders are matched for body height. Women have smaller and stiffer blood vessels resulting in an earlier return of the reflected wave, which is likely due to an increased pulse wave velocity in women.

Impact of physical and physiological factors on arterial function

1. Arterial function measurements are increasingly used as surrogate markers of cardiovascular disease and it is important to define which non-pathological factors may influence these measurements. 2. The present study examined the influence of gender, height, body mass index (BMI), waist : hip ratio, heart rate and arterial pressure on pulse wave velocity (PWV), systemic arterial compliance (SAC) and central pressure augmentation index (AI) in 285 normal subjects, 98 males and 187 females, aged 50-82 years. 3. There were significant gender differences in PWV (higher in men), SAC (higher in men) and central pressure AI (lower in men). 4. Both SAC and AI were correlated with height in men and women and height largely accounted for gender differences. 5. Systemic arterial compliance was positively, whereas AI was negatively, correlated with BMI. 6. Both PWV and AI were significantly correlated with heart rate and central pulse pressure. 7. These findings may have implications for cardiovascular disorders. Reduced central arterial compliance and increased central pressure augmentation are potential mediators for the increased cardiovascular risk of short stature. A slow heart rate may contribute to increased central arterial pressure with potentially adverse consequences in older subjects.

A placebo-controlled trial of long-term oral combined continuous hormone replacement therapy in postmenopausal women: effects on arterial compliance and endothelial function

OBJECTIVE

To study the effects of long-term combined continuous oral hormone replacement therapy (HRT) on vascular function in healthy postmenopausal women.

BACKGROUND

The cardiovascular effects of HRT are controversial. Improvement in vascular function is a proposed mechanism of oestrogen action but there are no long-term controlled human trials in this area. In this study, we examined the effects of HRT on lipid profiles and vascular function, encompassing both biomechanical arterial properties [systemic arterial compliance (SAC) and pulse wave velocity (PWV)] and endothelial function [flow-mediated vasodilation (FMD)].

METHODS

In this 2-year, double-blind, placebo-controlled study, 59 healthy postmenopausal women were randomized to oral combined continuous oestrogen and progesterone [Kliogest, oestradiol (2 mg), norethisterone (1 mg)] or placebo, with end-points measured at baseline, 6 weeks and after 6,12 and 24 months of treatment.

RESULTS

Oral combined HRT reduced lipoprotein a [Lp(a)], although other lipid benefits were not observed. There were no significant changes in SAC, PWV or FMD with oral combined HRT, compared to placebo.

CONCLUSION

In this long-term, randomized placebo-controlled trial, oral continuous HRT with combined oestradiol and norethisterone in healthy postmenopausal women did not improve a spectrum of indices of arterial function compared to placebo. These results suggest that HRT might not be of cardiovascular benefit in postmenopausal women.

Dietary soy has both beneficial and potentially adverse cardiovascular effects: a placebo-controlled study in men and postmenopausal women

To address the cardiovascular effects of dietary soy containing phytoestrogens, we measured blood pressure (BP), lipids, vascular function (systemic arterial compliance and pulse wave velocity), and endothelial function (flow-mediated vasodilation) in a randomized, double-blind trial. Two hundred thirteen healthy subjects (108 men and 105 postmenopausal women), 50-75 yr old, received either soy protein isolate (40 g soy protein, 118 mg isoflavones) or casein placebo for 3 months. There were 34 withdrawals (16%), with 179 subjects (96 men and 83 women) completing the protocol. After intervention in the soy group, compared with casein placebo, urinary phytoestrogens increased, accompanied by a significant fall in BP reflected by the BP model (P < 0.01) encompassing mean change (+/-SEM) in systolic (-7.5 +/- 1.2 vs. -3.6 +/- 1.1 mm Hg, P < 0.05), diastolic (-4.3 +/- 0.8 vs. -1.9 +/- 0.7 mm Hg, P < 0.05), and mean BP (-5.5 +/- 1 vs. -0.9 +/- 1 mm Hg, P < 0.008). In the lipid model, soy induced greater changes, compared with placebo (P < 0.001). On individual analysis, significant contributors included a reduction in the low- to high-density lipoprotein ratio (-0.33 +/- 0.1 vs. 0.04 +/- 0.1 mmol/L, P < 0.05) and triglycerides (-0.2 +/- 0.05 vs. -0.01 +/- 0.05 mol/L, P < 0.05) and an increase in Lp(a) lipoprotein (+/- 95% confidence interval) [42 (range, 17-67) vs. 4 (range, -22-31) mg/L, P < 0.05], whereas total, low-density lipoprotein, and high-density lipoprotein cholesterol improved in both groups; but no treatment effect was demonstrated. The arterial functional model demonstrated no difference between groups; although again, overall function improved in both groups. On individual analysis, peripheral PWV (reflecting peripheral vascular resistance) improved with soy (P < 0.01), whereas flow-mediated vasodilation (reflecting endothelial function) declined (in males only), compared with casein placebo (P < 0.02). No effect of treatment on the hypothalamic-pituitary-gonadal axis was noted in males or females. In normotensive men and postmenopausal women, soy improved BP and lipids but, overall, did not improve vascular function. Potential adverse effects were noted, with a decline in endothelial function (in males only) and an increase in Lp(a). Further research in hypertensive and hyperlipidemic populations is needed.

The effects of soy protein containing phytoestrogens on menopausal symptoms in postmenopausal women

OBJECTIVE

To analyze the impact of soy protein dietary supplements containing phytoestrogens on menopausal symptoms in healthy postmenopausal women.

METHODS

A double-blind, placebo-controlled trial was conducted in 94 healthy postmenopausal women aged 50-75 years, with 44 randomized to soy supplements containing 118 mg of isoflavones (daidzein, genistein, glycitein and their respective glycosides), and 50 to an identically presented casein placebo. A validated questionnaire on menopausal symptoms was administered at baseline and at 3 months of treatment. Compliance was assessed by high-performance liquid chromatography assay of urinary phytoestrogens. Statistical analysis was completed using non-parametric statistical methods and multivariate analysis.

RESULTS

At baseline 80% of women recruited were experiencing menopausal symptoms, although symptom severity was mild. Those consuming phytoestrogen supplements had 13- and 17-fold increases in urinary excretion of genistein and daidzein, respectively, with no change in the placebo group. Active soy supplements did not significantly alter either individual symptoms or specific symptom category scores when compared to placebo. Within-group comparisons revealed that the active group reported a significant improvement in vaginal dryness (p = 0.01), libido (p = 0.009), facial hair (p = 0.04) and dry skin (p = 0.027). However, similarly, those on placebo reported an improvement in libido (p = 0.015), facial hair (p = 0.014) and dry skin (p = 0.011) but not vaginal dryness.

CONCLUSIONS

In this group of 94 older postmenopausal women with a high frequency of mild menopausal symptoms, 3 months of soy supplements containing phytoestrogens did not provide symptomatic relief compared with placebo.

Carotid artery intima-medial thickness is increased in chronic renal failure

1. Chronic renal failure (CRF) is associated with rapidly progressive atherosclerotic vascular disease. In the present study, carotid arterial intima-medial thickness (IMT) was assessed in a large cohort of patients with CRF and matched controls and related to risk factors. 2. A total of 159 subjects with CRF (serum creatinine > or =0.40 mmol/L) aged > 50 years (mean (+/-SD) 63.8+/-7.7 years) and 159 healthy controls matched for age, sex and smoking status were studied. 3. The IMT was determined using B-mode ultrasound measurements of the far wall of both common carotid arteries and presented as the mean IMT. Fasting plasma homocysteine (tHcy) was measured in the CRF group. 4. Intima-medial thickness was significantly greater in CRF patients than controls (0.89+/-0.17 vs 0.73+/-0.13 mm, respectively) after matching for age, sex and smoking status. Heart rate and pulse pressure were also significantly increased. The tHcy was increased two-fold in the CRF group (27.7+/-11.3 micromol/L; normal < 13.0 micromol/L) and did not correlate with carotid IMT. 5. Compared with controls after adjusting for traditional risk factors, patients with CRF exhibit significantly increased IMT.

Postmenopausal hormone replacement therapy increases coagulation activity and fibrinolysis

Hormone replacement therapy (HRT) appears to be cardioprotective in postmenopausal women; however, concerns exist over its thrombogenic effects. To address the effects of combined HRT on coagulation and fibrinolysis, we have measured circulating markers of these processes in a double-blind placebo-controlled trial. Forty-two healthy postmenopausal women aged 50 to 75 years received continuous combined HRT with 2 mg estradiol+1 mg norethisterone or placebo for 6 weeks. Hormone profiles were measured at baseline, and lipid and hemostatic parameters were measured at baseline and after 6 weeks of therapy. Baseline characteristics were similar in the 2 groups. With change from baseline the main outcome measure, HRT increased the markers of coagulation (prothrombin fragments 1+2, 0.20+/-0.06 versus 0.06+/-0.04 nmol/L, P=0.0005; soluble fibrin, 2.3+/-0.4 versus 0.25+/-0.3 microgram/mL, P=0.0004), reduced plasma fibrinolytic inhibitory activity (plasminogen activator inhibitor-1, -0.67+/-0.16 versus 0.24+/-0.21 U/mL, P=0.002), and increased fibrinolysis (D-dimer, 24+/-12 versus -6+/-8 ng/mL, P=0.04) compared with placebo. Increases in soluble fibrin and D-dimer were positively correlated (r=0.59, P=0.02), but changes in plasminogen activator inhibitor-1 and D-dimer were unrelated. Although baseline hemostatic and lipid parameters were correlated, there were no associations between changes in hemostatic markers and lipids after treatment. Short-term oral combined continuous HRT (estradiol and norethisterone) increased thrombin and fibrin generation, reduced plasma fibrinolytic inhibitory activity, and increased fibrinolysis. Enhanced fibrinolysis was related to increased fibrin generation but not reduced plasma fibrinolytic inhibitory activity. Coagulation activation may partly explain the increases in venous thrombosis and cardiovascular events reported with the use of combined HRT.

Hormone replacement therapy in postmenopausal women protects against smoking-induced changes in vascular structure and function

OBJECTIVES

The purpose of this study was to investigate the role of hormone replacement therapy (HRT) in postmenopausal women who smoke.

BACKGROUND

Hormone replacement therapy appears to afford cardiovascular protection in postmenopausal women; however, in high risk individuals, specifically smokers, this has not been adequately studied. This question was addressed in a cross-sectional study of arterial structure, function and plasma lipids in postmenopausal smokers and nonsmokers.

METHODS

Vascular ultrasound was performed in two age-matched groups of postmenopausal women, 70 on HRT (35 smokers) and 70 control subjects not on HRT (35 smokers). Indexes of arterial structure (carotid intima-media thickness [IMT]) and vascular function (systemic arterial compliance [SAC]) and lipid profiles were measured.

RESULTS

Participant characteristics were similar in the two groups. Smokers on HRT, compared with smoking control subjects, had lower cholesterol (6.0+/-0.2 vs. 6.8+/-0.3 mmol/liter, p = 0.03) and more favorable mean values for IMT (0.64+/-0.02 vs. 0.74+/-0.03 mm, p = 0.007) and SAC (0.41+/-0.03 vs. 0.32+/-0.03 U/mm Hg, p = 0.03). Nonsmokers on HRT compared with nonsmoking control subjects had lower total cholesterol (5.7+/-0.2 vs. 6.5+/-0.2 mmol/liter, p = 0.02) and low density lipoprotein cholesterol (3.4+/-0.2 vs. 4.4+/-0.3 mmol/liter, p = 0.01). Mean IMT and SAC values in nonsmokers on HRT and control subjects were not significantly different. Multiple regression demonstrated significant correlation between HRT status and both IMT and SAC, in smokers and in those with increased cholesterol. In nonsmokers and those with lower cholesterol, HRT status was not significantly correlated with vascular parameters.

CONCLUSIONS

In postmenopausal women who smoke there may be a beneficial effect of long-term estrogen therapy on indexes of arterial structure and function as surrogate markers of cardiovascular disease. Long-term controlled studies are needed to confirm these findings.

Effects of heart rate on arterial compliance in men

1. Arterial compliance is a major determinant of left ventricular afterload. In keeping with earlier experimental data obtained in isolated arterial segments, it has recently been shown in the rat that arterial compliance decreases with an increase in heart rate (HR) induced by atrial pacing. 2. To elucidate the potential relevance of this effect in humans, we investigated nine male volunteers (age 20-30 years; mean 26 years). Systemic arterial compliance (SAC) was measured with the diastolic area method and carotid-to-femoral and femoral-to-dorsalis pedis pulse wave velocities (PWV) were measured to determine regional changes in compliance. Heart rate was first lowered with intravenous metoprolol to 56 +/- 2 b.p.m. and then increased by transoesophageal atrial pacing to 80 and 100 b.p.m. 3. Increasing HR from 56 +/- 2 to 80 b.p.m. by pacing increased mean arterial pressure (MAP) from 78 +/- 2 to 98 +/- 1 mmHg (P < 0.001) and then to 102 +/- 2 mmHg (P = NS). Systemic arterial compliance fell from 0.48 +/- 0.06 to 0.33 +/- 0.04 arbitrary compliance units (ACU; P < 0.01), carotid-to-femoral PWV increased from 6.1 +/- 0.3 to 6.8 +/- 0.4 m/s (P < 0.001) and femoral-to-dorsalis pedis PWV increased from 8.9 +/- 0.4 to 10.1 +/- 0.5 m/s (P < 0.001). Pacing at 100 b.p.m did not change MAP, but did lead to a further decrease in SAC (to 0.24 +/- 0.03 ACU; P < 0.05) and further increases in carotid-to-femoral (7.3 +/- 0.4 m/s; P = NS) and femoral-to-dorsalis pedis PWV (11.3 +/- 0.4 m/s; P < 0.001). 4. We conclude that systemic, central and peripheral compliances decrease in vivo with an increase in HR induced by atrial pacing.

Non-invasive measurements of arterial structure and function: repeatability, interrelationships and trial sample size

1. Repeatability of measurements of arterial compliance and flow-mediated dilation of the brachial artery has been infrequently reported, despite increasing use in interventional and risk-factor modification studies. Furthermore, little is known about the interrelationships of the various indices. The purposes of this study were to determine the repeatability and interrelationships of a range of arterial indices.2. Fifty healthy volunteers, 20 men and 30 women, aged 20-70 (mean 46.5) years, were studied on two occasions, using an identical protocol, at a mean interval of 2.5 weeks. Tonometry, ultrasound and Doppler technique were used to measure the following: carotid wall intima-media thickness (IMT), total systemic artery compliance (SAC), arterial pulse wave velocity [PWV aorto-femoral (A-F), and femoral-dorsalis pedis (F-D)], carotid distensibility coefficient (DC) and carotid augmentation index (AI). Brachial flow-mediated dilation was measured in 30 subjects with analysis of diameter change for 4 min post ischaemia.3. There were no systematic differences over the observed range of measurements for any of the reported parameters. Coefficients of variation were as follows: IMT 2.8%, SAC 9.2%, PWV(A-F) 3.2%, PWV(F-D) 5.0%, DC 10.0%, AI 1.3%. Brachial flow-mediated dilation curves were not different between visits; changes were maximum 60-s post ischaemia. All indices of arterial compliance were significantly correlated with age. The three different indices of central arterial compliance [SAC, PWV(A-F) and AI] were significantly correlated with carotid intima-media thickness.4. Under controlled experimental conditions there was good repeatability of measurements of indices between sessions of both intrinsic and functional arterial mechanical properties (central and carotid arterial compliance, intima-media thickness and brachial flow-mediated dilation). Sample size tables for clinical trials using these indices are presented.

Reproducibility of arterial compliance and carotid wall thickness measurements in normal subjects

1. Non-invasive techniques to measure indices of arterial function and wall thickness are frequently used as surrogate markers of cardiovascular disease. Reproducibility of measurements of arterial compliance has been infrequently reported and little is known about the interrelationships of the various indices in vivo. 2. The present study was designed to assess reproducibility and interrelationships of indices of systemic arterial compliance, pulse wave velocity, carotid compliance and intima-media thickness (IMT). 3. Fifty healthy volunteers (20 male and 30 female: aged 20-70 years, mean 46.5 years), participated in the present study. Each subject was studied on two occasions by the same investigators, using an identical protocol at an interval of 1-5 weeks (mean 2.5 weeks) without lifestyle change. 4. There were no significant differences between visits for any recorded general data, except resting blood pressure, which was lower on the second occasion. There were no systematic differences within each pair over the range of measurements for any of the variables. Bland-Altman plots of repeatability of changes in indices showed that the mean values between visits were not significantly different. All indices of central arterial compliance were significantly related to age and IMT. 5. Thus, under controlled experimental conditions, there was satisfactory repeatability of measurements of indices of both intrinsic and functional arterial mechanical properties (central and carotid arterial compliance and IMT). This type of information will permit the construction of sample size tables for clinical trials using these indices. 6. Central arterial compliance may be an important determinant of IMT.

Age-related deterioration in arterial structure and function in postmenopausal women: impact of hormone replacement therapy

Epidemiological evidence suggests that hormone replacement therapy (HRT) reduces morbidity and mortality from cardiovascular diseases in postmenopausal women. In this study, indices of arterial function [total systemic arterial compliance (SAC) and carotid arterial distensibility coefficient (DC)], structure [carotid intima-media thickness (IMT)], and lipid profiles were compared in postmenopausal women on long-term HRT and aged-matched controls. One hundred nine women aged 44 to 77 years taking HRT and an age-matched group of 108 female controls were entered into the study. The two groups were similar for body mass index, smoking status, exercise level, alcohol intake, and blood pressure. Fasting cholesterol, low density lipoprotein, and lipoprotein(a) were reduced and high density lipoprotein increased in the HRT group. IMT increased with age; SAC and DC were reduced with age in both groups. The HRT group had a higher mean SAC (0.42+/-0.02 versus 0.34+/-0.02 U/mm Hg, P=0.0001) and a lower mean IMT (0.67+/-0.01 versus 0.74+/-0.02 mm, P=0.006) than did controls. Subgroup analysis for estrogen versus estrogen plus progestin revealed no differences for SAC and IMT; DC, however, was greater in estrogen-only users. Smokers on HRT had a higher mean SAC (0.41+/-0.02 versus 0.31+/-0.01 U/mm Hg, P=0.008) and a lower IMT (0.65+/-0.02 versus 0.75+/-0.03 mm, P=0.002) than did smokers not taking such therapy. A protective effect of long-term estrogen therapy on age-related changes in arterial structure and function in postmenopausal women was evident in smokers and nonsmokers alike. Progestin appeared to counteract the effects of estrogen on carotid compliance only. Long-term controlled trials are needed to determine the significance of these findings.

Effects of oestrogen and progesterone on age-related changes in arteries of postmenopausal women

1. Hormone replacement therapy (HRT) with oestrogen or oestrogen plus progestin may have different effects on arterial structure and function. To examine this question, carotid artery intima-medial thickness (IMT) and indices of systemic and carotid arterial compliance were measured in groups of older men, postmenopausal women not on HRT (non-HRT) and those women on long-term HRT with oestrogen alone (HRT-E) or oestrogen plus progestin (HRT-EP). 2. Sixty men, 90 postmenopausal women taking HRT and 91 not taking HRT participated in the study. The groups were similar for age, body mass index, numbers of smokers, physical activity, alcohol intake and blood pressure. 3. Plasma total cholesterol was reduced and high-density lipoprotein-cholesterol was increased in the HRT group compared with the non-HRT group; low-density lipoprotein-cholesterol, triglyceride and lipoprotein (a) values were similar in these two groups. Results for HRT-E and HRT-EP subgroups were similar. 4. Carotid IMT was significantly reduced in the HRT group compared with men and non-HRT groups. Results for HRT-E and HRT-EP subgroups were similar. 5. Mean systemic arterial compliance (SAC) was significantly greater in men than in women and was related to age; SAC was higher in both HRT-E and HRT-EP groups compared with the non-HRT group. Indices of carotid stiffness were similar in men and in non-HRT groups. The HRT-EP group showed increased carotid stiffness compared with the HRT-E group. 6. There is an apparent protective effect of long-term oestrogen therapy on carotid IMT and age-related changes in arterial stiffness. Progestin does not alter the IMT effects but may adversely influence arterial stiffness.

Arterial compliance in obese subjects is improved with dietary plant n-3 fatty acid from flaxseed oil despite increased LDL oxidizability

The compliance or elasticity of the arterial system, an important index of circulatory function, diminishes with increasing cardiovascular risk. Conversely, systemic arterial compliance improves through eating of fish and fish oil. We therefore tested the value of high intake of alpha-linolenic acid, the plant precursor of fish fatty acids. Fifteen obese people with markers for insulin resistance ate in turn four diets of 4 weeks each; saturated/high fat (SHF), alpha-linolenic acid/low fat (ALF), oleic/low fat (OLF), and SHF. Daily intake of alpha-linolenic acid was 20 g from margarine products based on flax oil. Systemic arterial compliance was calculated from aortic flow velocity and aortic root driving pressure. Plasma lipids, glucose tolerance, and in vitro LDL oxidizability were also measured. Systemic arterial compliance during the first and last SHF periods was 0.42 +/- 0.12 (mean +/- SD) and 0.56 +/- 0.21 units based on milliliters per millimeter of mercury. It rose significantly to 0.78 +/- 0.28 (P < .0001) with ALF; systemic arterial compliance with OLF was 0.62 +/- 0.19, lower than with ALF (P < .05). Mean arterial pressures and results of oral glucose tolerance tests were similar during ALF, OLF, and second SHF; total cholesterol levels were also not significantly different. However, insulin sensitivity and HDL cholesterol diminished and LDL oxidizability increased with ALF. The marked rise in arterial compliance at least with alpha-linolenic acid reflected rapid functional improvement in the systemic arterial circulation despite a rise in LDL oxidizability. Dietary n-3 fatty acids in flax oil thus confer a novel approach to improving arterial function.

Influences of solvent on group transfer potentials and biochemical recognition of carbohydrates. Anomalous solvation of the anomeric hydroxyl group

When carbohydrates in aqueous solution combine with biological receptors, their interactions with the binding site take the place of previous interactions with solvent water. Free energies of binding can therefore be considered to depend on free energies of solvation of the interacting partners before and after complexation. Because carbohydrates contain so many polar substituents, their overall preferences for aqueous surroundings are overwhelming, so that they do not yield readily to analysis of their solvation properties. We therefore decided to eliminate most of the secondary hydroxyl groups and to compare the distribution properties of simple sugar analogs based on tetrahydropyran. The results suggest that compounds containing an anomeric hydroxyl group are less strongly solvated than expected from the properties of simple alcohols. Group transfer potentials of O- and N-glycosides, lactones, and acylals are substantially affected by differences in free energy of solvation between reactants and products. In contrast, equilibria of ring chain tautomerism and covalent hydration of aldoses are almost completely insensitive to the polarity of their surroundings.