[Progress in the application of alveolar organoids in common lung diseases]

Organoids are tissue cultures formed by culturing cells in three-dimensional environments that simulate the physiological or pathological conditions of the human body. The cultivation of organoids is used to study the temporal and spatial transformation of cells during the development of tissues or organs, to investigate changes in cellular functions and inter-communications caused by various risk factors, and to discover potential therapeutic targets. This article provided an overview of the cultivation and identification methods of alveolar organoids, as well as the research progress in their application to common respiratory diseases such as pulmonary fibrosis, chronic obstructive pulmonary disease, viral pneumonia, and so on. The limitations and future applications of alveolar organoids are also analyzed and discussed.

[Five-year immunity persistence following immunization with haemophilus influenzae type b conjugate vaccine]

Objective: To evaluate the immunity persistence five years later after immunization with Haemophilus influenzae type b (Hib) conjugate vaccine in healthy infants/children aged 3 months to 5 years in China. Methods: The children were subjects who completed the whole-schedule immunization in the phase Ⅲ clinical trial in Lianshui county of Jiangsu povince was selected for the collection of blood samples at 5 years after vaccination from November to December, 2019. The enzyme-linked immunosorbent assay (ELISA) was used to detect Hib polyribosyl-ribitol-phosphate antibody (anti-Hib-PRP), and the long-term/short-term protection rate, geometric mean concentration (GMC) and geometric mean concentration increase fold (GMFI) of serum anti-Hib-PRP were calculated. Results: A total of 580 children were enrolled in this study, of which 158, 207 and 215 belonged to 3-5 month age group, 6-11 month age group and 1-5 year age group, respectively. The short-term (≥0.15 μg/ml)/long-term (≥1.0 μg/ml) protection rates of serum anti-PRP in the three groups after immunization were 89.24%, 90.34% and 98.60%, respectively; the GMC were 3.95 μg/ml, 3.11 μg/ml and 10.01 μg/ml respectively, and the GMFI were 29.04, 11.01 and 3.26 respectively. Conclusions: Hib conjugate vaccine can still have good immunogenicity after 5 years of primary immunization in healthy infants/children aged 3 months to 5 years in China.

Nomogram to predict haemorrhagic transformation after stroke thrombolysis: a combined brain imaging and clinical study

AIM

To construct a novel nomogram by integrating computed tomography perfusion (CTP) and clinical parameters for individualised prediction of haemorrhagic transformation (HT) in intravenous thrombolysis (IVT)-treated acute ischaemic stroke (AIS) patients.

METHODS

Anterior circulation AIS patients who underwent IVT at a single centre from January 2018 to June 2020 were reviewed retrospectively. The CTP parameters of two regions of interest (ROI), the entire perfusion lesion areas, and the infract core areas, were assessed. HT was documented by follow-up CT 24 ± 2 h after IVT. Multivariable logistic regression was conducted by including clinical variables and CTP parameters to identify the independent predictors of HT. A nomogram was developed based on the independent predictors. The discriminative value and calibration of the nomogram were tested by concordance indexes (C-indexes) and calibration plots. Internal validation was performed using fivefold cross-validation.

RESULTS

The nomogram was generated using the complete data from 341 patients. Seven variables were included in the final nomogram, including: the relative cerebral blood volume (rCBV), permeability surface (PS), and relative PS (rPS) in infract core areas, the relative time to maximum (rTmax) and rPS in entire perfusion lesion areas, the National Institutes of Health Stroke Scale (NIHSS), and atrial fibrillation (AF). The C-indexes were 0.815 and 0.817 for the nomogram and internal validation. The calibration plots showed excellent agreement.

CONCLUSION

This is the first study establishing a nomogram based on CTP and clinical parameters to predict HT after stroke thrombolysis.

[Utility of the type 3 portable monitor for the diagnosis of sleep disordered breathing in patients with stable heart failure]

Objective: To evaluate the utility of a type 3 portable monitor (PM) at home for the diagnosis of sleep disordered breathing (SDB) in patients with stable congestive heart failure (CHF). Methods: Seventy-six consecutive patients with CHF (61 males, 15 females, mean±standard deviation age (57.0±16.9) years) were enrolled from the sleep center of Peking university People's Hospital during January 2016 to January 2019, and underwent overnight, unattended home sleep apnea testing (HSAT) with a portable monitor followed by an overnight simultaneous polysomnogram (PSG) with in-laboratory portable monitor (in-lab PM) recording within one week. The consistency of apnea hypopnea index (AHI), obstructive sleep apnea index (OAI), central sleep apnea index (CAI) between HSAT and PSG as well as the in-lab PM and PSG were analyzed by Bland-Altman plot; the sensitivity and specificity of PM for the diagnosis of SDB in patients with CHF were evaluated. Results: The number of patients included in the final analysis were 65 in HSAT, 63 in in-lab PM and 65 in PSG. AHI [M(Q₁,Q₃)] was 26.1 (10.9,40.1) events/h by HSAT, 27.9 (11.3,43.2) events/h by in-lab PM, both were not different from AHI 29.0 (10.2,45.0) events/h by PSG (P>0.05). The AHI, OAI and CAI assessed by HSAT correlated significantly with those by PSG (r=0.892, 0.903, 0.831, P<0.05). Bland-Altman analysis of AHI, OAI, CAI by PSG versus HSAT showed a mean difference of 3.1 events/h, 0.8 events/h, 1.2 events/h; limits of consistency were -15.2 to 21.4 events/h, -9.7 to 11.3 events/h, -10.9 to 13.2 events/h, respectively. Based on a threshold of AHI ≥5 events/h, HSAT had 94.6% sensitivity, 75% specificity, compared to PSG. For detecting Cheyne-Stokes respiration (CSR), a sensitivity of 96.4%,a specificity of 97.2% were achieved, compared to PSG. Conclusion: Type 3 PM can be used to diagnose SDB in patients with CHF.

CLIC1 knockout inhibits invasion and migration of gastric cancer by upregulating AMOT-p130 expression

PURPOSE

To explore the regulatory relationship between Chloride intracellular channel 1 (CLIC1) and Angiomotin (AMOT)-p130, and reveal the role of AMOT-p130 in gastric cancer (GC).

METHODS

Immunohistochemistry was performed to analyze the expression of CLIC1 and AMOT-p130 in GC tissues and adjacent tissues. The expression of AMOT-p130 upon CLIC1 silencing was analyzed using RT-PCR, western blot, and immunofluorescence in GC cells. Transwell and wound-healing assays were performed to detect migration and invasion in GC cells. The changes in EMT-related proteins were detected using western blot.

RESULTS

Our study found that high CLIC1 expression was significantly associated with low AMOT-p130 expression in GC tissues. Silencing CLIC1 expression in MGC-803 cells (MGC-803 CLIC1 KO) and AGS cells (AGS CLIC1 KO) decreased the invasive and migratory abilities of tumor cells, which were induced by the upregulation of AMOT-p130. Subsequently, we demonstrated that AMOT-p130 inhibits the invasive and migratory abilities of GC cells by inhibiting epithelial-mesenchymal transition.

CONCLUSIONS

Our study suggests that AMOT-p130 could inhibit epithelial-mesenchymal transition in GC cells. CLIC1 may participate in the metastatic progression of GC by downregulating the expression of AMOT-p130.

[Influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV]

Objective: To explore influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV (PMTCT) in Guangxi Zhuang autonomous region, and provide evidence for the improvement PMTCT program. Methods: This retrospective case control study was conducted in 554 HIV negative infants aged 18 months whose HIV positive mothers had received PMTCT services reported through PMTCT system database from January 1, 2010 to December 31, 2017 and 1 109 healthy infants born in 2017, whose mothers were healthy, in Lingshan, Luzhai, and Hengxian counties, ranking top three counties with high HIV infection prevalence, in Guangxi. PMTCT data and physical development data such as height, weight and head circumference of children aged 18 months were collected. The physical dysplasia in the infants was defined as at least one of the three main indicators of height, weight and head circumference below the normal range. Results: The number of HIV-positive mother and their infants in the case group were 667 and 554 respectively, and the PMTCT rates were 91.15% (608/667) and 96.57% (535/554) respectively. HIV positive rate, mortality rate and mother to child transmission rate of the infants aged 18 months were 1.44% (8/554), 3.07% (17/554) and 1.91% (8/418) respectively, and the physical examination results of the infants aged 18 months showed that the physical dysplasia rate was 30.51% (169/554). Among the 1 109 infants in the control group, the physical dysplasia rate was 9.83% (109/1 109). The difference between the case group and the control group was significant (P<0.01). Conclusion: The PMTCT rates of HIV positive mother and their children were more than 90.00%, respectively. However, poor physical development rate of infants aged 18 months were more than 30.00%. The possible influence of PMTCT on physical development of the infants aged 18 months of HIV positive mother's needs to be further studied.

[Accuracy analysis of robotic assistant needle placement for trigeminal gasserian ganglion]

OBJECTIVE

To evaluate the accuracy and feasibility of a custom robot system guided by optical navigation for needle puncture on trigeminal gasserian ganglion.

METHODS

A synthetic human skull model was used, with plasticine placed around the skull base to imitate the human soft tissue. Cone beam CT (CBCT) scanning was performed before the operation. With image data transferred to the graphical user interface of the computer workstation, the oval foramen was selected as the target and the "skin entry point" was also determined by the surgeon on the surgical planning software. Thus the needle trajectory was eventually planned. The skull model was fixed firmly to the trial table with a head clamp and relative size of the trial table was the same as a standard operating table. Following point-based registration, the data were sent to the robot control unit. Only after the surgeon's confirmation, the needle was automatically inserted into the intended target by the robot guided by optical navigation. When the procedure was completed, the instantaneous data of the needle tip orientation acquired by navigation system was sent back to the computer workstation for accuracy verification by calculating the geometric distance between the needle tip and the planning target after matrix transformation. Subsequently, after the needle had been released, CBCT scanning was also acquired to make image fusion of the preoperative skull and the postoperative skull. The data of the needle tip orientation was acquired on the postoperative image and the accuracy was re-verified by calculating the geometric distance between the needle tip and the planning target after matrix transformation. IBM SPSS Statistics 20 was used for statistical analysis and the paired t-test was used to compare the differences in the accuracy measured by the intraoperative navigation and postoperative image fusion.

RESULTS

All 20 interventions were successfully located in oval foramen at the first needle insertion. The mean deviation of the needle tip was (0.56±0.07) mm (measured by the navigation system) and (1.49±0.14) mm (measured by the image fusion), respectively (P<0.001).

CONCLUSION

The experimental results show the robot system is efficient and reliable. The navigation accuracy is one of the most significant factors in robotic procedures.

[Evaluation of strain indexes and prognosis of patients with cardiac amyloidosis with preserved LVEF by three-dimensional speckle tracking imaging]

Objective: To evaluate the patients with Cardiac amyloidosis (CA) and Hypertrophic cardiomyopathy (HCM) by using the strain indexes of three-dimensional speckle tracking imaging(3D-STI) technique, and to evaluate the prognosis. Methods: A total of 32 patients with pathologically confirmed cardiac amyloidosis and 34 patients with hypertrophic cardiomyopathy and 16 normal controls were enrolled from the First Affiliated Hospital of Zhejiang University College of Medicine from June, 2013 to January, 2018.The color Doppler echocardiography and three-dimensional speckle tracking echocardiography were used to measure strain indexes of each group, and the Logistic regression equation was used to analyze the index differences.The cut-off values were analyzed using the Receiver Operating Characteristic (ROC), and Kaplan-Meier and Cox were used for survival regression analysis. Results: The globe radial strain (GRS) (16%±7% vs 23%±9%), left ventricular wall peak time difference (PSD) (52 ms±17 ms vs 77 ms±25 ms), Sokolow-Lyon index (20 mm±6 mm vs 34 mm±14 mm) were significantly different between cardiac amyloidosis group and hypertrophic cardiomyopathy group by 3D-STI, which had high sensitivity and specificity by Logistic regression analysis.The area under the ROC curve of GRS was 0.725, PSD was 0.812, Sokolow-Lyon index was 0.832.In addition, the area strain and atrial septal thickness were significant prognostic factors according to survival regression analysis. Conclusions: For the differential diagnosis of cardiac amyloidosis with preserved LVEF, unlike echocardiographic parameters, the 3D-STI strain indicators could be used to differentiate cardiac amyloidosis from hypertrophic cardiomyopathy, reflecting obvious diagnostic advantages.When combined with area strain and atrial septal thickness, 3D-STI strain indicators could be used to predict the survival prognosis, which are important in clinical practice.

[Accuracy analysis of robotic assistant needle placement for lateral skull base biopsy]

Objective: To evaluate the accuracy and feasibility of a custom robot system guided by navigation for lateral skull base tumor biopsy. Methods: Two cadaver heads were used, with iopamidol injected into different areas in the skull base and infratemporal region to imitate the tumor. Cone beam CT (CBCT) scanning was performed before operation. With image data transferred to the graphical user interface of the computer workstation, the "tumor" was segmented as the target. The needle trajectory was determined by selecting the skin entry point and the target point on the surgical planning software. Following point-based registration, the data was sent to the robot control unit. The needle was automatically inserted into the intended target by the robot guided by optical navigation. After the procedure was performed, the instantaneous data of needle tip position acquired by navigation system was sent back to the computer workstation for accuracy verification. Subsequently, after the needle was released, CBCT scanning was performed again, and the pre-and post-operative skull were superimposed. The position data of needle tip was acquired on the postoperative image and the accuracy was re-verified. The paired t-test was used to compare the differences in the accuracy calculated by intraoperative navigation and postoperative image fusion. The independent samples t-test was used to compare the accuracy between the cadavers. The Pearson correlation coefficients (r) was used to analyze correlation between the needle intervention accuracy and insertion depth. Results: All 20 interventions were successfully performed. The mean deviation of the needle tip was (0.67±0.28) mm (measured by the navigation system) and (3.19±0.39) mm (measured by image fusion) respectively (t=-23.238, P<0.001). The comparison of accuracy test showed no significant difference between the cadavers (t=-1.116, P=0.279). Pearson correlation coefficients (r=0.714, P<0.001) showed the close correlation between the needle intervention accuracy and insertion depth. The mean insertion depth was (5.14±0.21) cm. Conclusions: The experimental results show that the robot system is efficient and reliable. The navigation accuracy and the needle deflection are the most significant factors affecting robotic puncture procedures.

[Treatment of patients with different degree of acute respiratory distress syndrome caused by inhalation of white smoke]

Objective: To summarize the treatment experience of patients with different degree of acute respiratory distress syndrome (ARDS) caused by inhalation of white smoke from burning smoke bomb. Methods: A batch of 13 patients with different degree of ARDS caused by inhalation of white smoke from burning smoke bomb, including 2 patients complicated by pulmonary fibrosis at the late stage, were admitted to our unit in February 2016. Patients were divided into mild (9 cases), moderate (2 cases), and serious (2 cases) degree according to the ARDS Berlin diagnostic criteria. Patients with mild and moderate ARDS were conventionally treated with glucocorticoid. Patients with severe ARDS were sequentially treated with glucocorticoid and pirfenidone, and ventilator-assisted breathing, etc. were applied. The vital signs, arterial oxygenation index, changes of lung imaging, pulmonary ventilation function, general condition, and the other important organs/systems function were timely monitored according to the condition of patients. The above indexes were also monitored during the follow-up time of 10-15 months post injury. Data were processed with SPSS 18.0 statistical software. Results: (1) The symptoms of respiratory system of patients with mild and moderate ARDS almost disappeared after 3 days' treatment. Their arterial oxygenation index was decreased from post injury day 1 to 4, which almost recovered on post injury day 7 and completely recovered one month post injury. The symptoms of respiratory system of patients with severe ARDS almost disappeared at tranquillization condition 1-3 month (s) post injury. Their arterial oxygenation index was decreased from post injury day 3 to 21, which gradually recovered 1-3 month (s) post injury and was normal 15 months post injury. (2) Within 24 hours post injury, there was no obvious abnormality or only a little texture enlargement of lung in image of chest CT or X-rays of patients with mild and moderate ARDS. One patient with moderate ARDS had diffuse patchy and ground-glass like increased density shadow (pulmonary exudation for short) at post injury hour 96. Chest iconography of all patients with mild and moderate ARDS showed no abnormalities 10 months post injury. Both lungs of each of the two patients with severe ARDS showed obvious pulmonary exudation at post injury hours 45 and 75, respectively. One patient with severe ARDS showed no abnormality in chest image 10 months post injury, but there was still a small mesh-like increased density shadow in double lobes with slight adhesion of pleura in the other patient with severe ARDS 15 months post injury. (3) All patients showed severe restrictive hypoventilation when admitted to hospital. Pulmonary ventilation function of patients with mild and moderate ARDS recovered to normal one month post injury, and they could do exercises like running, etc. Pulmonary ventilation function of one patient with severe ARDS recovered to normal 6 months post injury, and the patient could do exercises like running, etc. The other patient with severe ARDS showed mild restrictive hypoventilation 15 months post injury and could do exercises like rapid walking, etc. (4) The condition of all mild and one moderate ARDS patients was better on post injury day 3, and they were transferred to the local hospital for subsequent treatment and left hospital on post injury day 21. One patient with moderate ARDS healed and left hospital on post injury day 29. Patients with severe ARDS healed and left hospital on post injury day 81. During the follow-up time of 10-15 months post injury, the other important organs/systems of all patients showed no abnormality, and there was no adverse reaction of glucocorticoid like osteoporosis, femoral head necrosis, or metabolic disorder. Two patients with severe ARDS did not have any adverse reaction of pirfenidone like liver function damage, photosensitivity, anorexia, or lethargy. Conclusions: Early enough and uninterrupted application of glucocorticoid can significantly reduce the ARDS of patients caused by inhalation of white smoke from burning smoke bomb. Sequential application of glucocorticoid and pirfenidone can effectively treat pulmonary fibrosis at the late stage.

[Analysis of related factors on effects of uterine artery embolization in the treatment of dysmenorrhea of adenomyosis and the construction and validation of prediction model]

Objective: To investigate the related factors on effects of uterine artery embolization(UAE)in the treatment of dysmenorrhea in patients with adenomyosis, and to construct and validate the efficacy prediction model. Methods: A total of 127 cases of adenomyosis patients with symptoms of dysmenorrhea in Guangzhou No.1 People's Hospital and Nanfang Hospital of Southern Medical University from June 1999 to December 2009 were reviewed. The evaluation standard was to improve the degree of dysmenorrhea, the related factors of efficacy were analysed. Combined with artificial neural network theory, the effect prediction model was constructed, and the effectiveness of the model was evaluated using receiver operating characteristic(ROC)curve, and the effectiveness of the cut-off point was calculated. The model was validated by 68 cases of patients with adenomyosis in the Nanfang Hospital from January 2010 to November 2014. Results: (1)In 127 cases of dysmenorrhea patients, UAE treatment was effective in 98 cases, effective rate was 77.2%(98/127).(2)Age was an independent predictor of effective UAE treatment(HR= 1.129, P=0.026); in the range of this study, the greater the age, the higher the UAE treatment efficiency.(3)The developing situation of ovary branches of uterine artery was an independent predictor of effective UAE treatment(HR=0.460, P=0.020), the efficiency of patients whose intraoperative bilateral uterine artery ovarian branch did not develop was 89.7%(35/39), the efficiency of patients whose unilateral uterine artery ovarian branch was developing was 84.1%(37/44)and the efficiency of patients whose bilateral uterine artery ovarian branch were developing was 59.1%(26/44).(4)Blood supply of adenomyosisis was an independent predictor of effective UAE treatment(HR=0.313, P=0.001). Type Ⅰ(bilateral predominated)patients, efficiency was 93.5%(43/46); type Ⅱ(bilateral balanced)patients, efficiency was 78.0%(39/50); type Ⅲ(unilateral predominated)patients, efficiency was 51.6%(16/31).(5)UAE for the treatment of adenomyosis efficacy of artificial neural network prediction model was constructed, the model's area under the ROC curve was 0.808, the optimal cut-off point was 0.669 13. Actual verification of the model, sensitivity was 96.5%, specificity was 81.8%, positive predictive value was 96.5% and negative predictive value was 81.8%, the total accuracy was 94.1%. Conclusions: (1)Age, the developing situation of ovary branches and blood supply of adenomyosis are the independent predictors of effective UAE treatment.(2)The artificial neural network prediction model is satisfied with the accuracy and the accuracy of prediction.

Sensitive and rapid detection of Pectobacterium atrosepticum by targeting the gyrB gene using a real-time loop-mediated isothermal amplification assay

This study reports the development of a real-time, loop-mediated isothermal amplification (RealAmp) assay for the detection of Pectobacterium atrosepticum (P. atrosepticum). A phylogenetic tree was constructed based on the gyrB gene of P. atrosepticum and related species. Pectobacterium atrosepticum from different sources can be clustered in the same branch with 100% support rate. The RealAmp primers targeting the gyrB gene of P. atrosepticum worked most efficiently at 61·0°C. Compared with 55 related bacterial strains, the eight P. atrosepticum strains displayed positive reaction in the RealAmp assay. The melting temperature (Tm) of P. atrosepticum amplified products was about 85·0°C. The detection limit of the RealAmp assay for the detection of P. atrosepticum in pure culture was approx. 3 CFU reaction(-1) . The detection limit of the RealAmp assay for the detection of P. atrosepticum in artificially contaminated samples was 22 CFU reaction(-1) . The detection rate of the RealAmp assay for the detection of potato tubers was 28·5-32·0% higher than that of the conventional PCR. In summary, a specific, sensitive and rapid RealAmp assay based on the gyrB gene of P. atrosepticum, which can be easily performed and real-time monitored, was established.

SIGNIFICANCE AND IMPACT OF THE STUDY

Potato blackleg caused by Pectobacterium atrosepticum (P. atrosepticum) which is mainly transmitted through the seed potato leads to the decline in potato production. To reduce yield loss, rapid detection of P. atrosepticum in seed potato remains essential. Based on the gyrB gene of P. atrosepticum, species-specific primers were designed. A real-time, loop-mediated isothermal amplification (RealAmp) assay was established for the detection of P. atrosepticum. The RealAmp assay is a specific, rapid and sensitive method for P. atrosepticum detection. Therefore, it provides an effective diagnosis of potato blackleg in both the growing and stored potato.

Chromosome 7 translocation breakpoints in male carriers: clinical features and implications for genetic counseling

Balanced reciprocal translocations are associated with reproductive failure. Some reciprocal translocation carriers exhibit azoospermia or oligozoospermia, and an association exists between these chromosomal abnormalities and recurrent abortion. Previous reports have indicated the involvement of chromosome 7 translocations in male infertility and recurrent miscarriage. A translocation breakpoint can occur within an important gene, interrupting its structure and leading to male infertility. However, clinical characteristics resulting from chromosome 7 translocation breakpoints have not been studied. Here, we report such breakpoints and their associated clinical features, to enable informed genetic counseling of carriers. Balanced reciprocal translocations were found in 1.57% of the tested patients. Among these 82 individuals, 14 (17.07%) carried a chromosome 7 translocation, of which, five presented with pregestational infertility and clinical manifestations of oligozoospermia or necrospermia, while nine presented with gestational infertility (i.e., were able to conceive, but often resulting in miscarriage). Breakpoints at 7q31 and 7q36 were associated with pregestational infertility, whereas those at 7p10, 7q21.2, 7q22, and 7q32 were connected to gestational infertility. However, the breakpoint at 7p15 was associated with both. Chromosome 7 translocation carriers with pregestational or gestational infertility should be counseled on chromosomal breakpoints and the various molecular technologies available for assisted reproduction.

Lack of association between the aryl hydrocarbon receptor rs2066853 polymorphism and breast cancer: A meta-analysis on Ahr polymorphism and breast cancer

Published data regarding the association between aryl hydrocarbon receptor (Ahr) rs2066853 polymorphism and the risk of breast cancer shows conflicting results. We performed a meta-analysis on 2999 patients and 3050 controls from three related case-control studies to estimate the association between Ahr rs2066853 polymorphism and the risk of breast cancer. The protocol was approved by the Institutional Animal Care and Use Committee (IACUC) at the University of Florida (America NIH Publication No. 86-231985 Revision). According to the three eligible populations, the odds ratios (ORs), 95% confidence intervals (CIs) on the risk of breast cancer for the genotypes GA vs GG, AA vs GG, and A vs G were 1.06 (0.81-1.40), 0.96 (0.81-1.13), and 1.02 (0.85-1.22), respectively. The OR (95%CI) for GA + AA vs GG was 1.05 (0.80-1.37). Furthermore, after multi-variates adjustment, the ORs (95%CIs) were 1.05 (0.80-1.38) for GA vs GG, and 0.92 (0.76-1.10) for AA vs GG. This meta-analysis suggests that Ahr (rs2066853) polymorphism would not modify the risk of breast cancer. However, further research should be conducted to provide more evidence.

Clinical significance and levels of blood brain natriuretic peptides in patients with persistent atrial fibrillation before and after catheter ablation

The aim of this study was to observe levels of blood brain natriuretic peptides (BNPs) in patients with persistent atrial fibril-lation (AF) before and after catheter ablation. Thirty-six patients with persistent AF (28 successful surgeries and eight recurrent cases) and 36 healthy controls with normal sinus rhythm were recruited for this study. BNP levels in the AF and control groups were measured before and after catheter ablation. BNP levels before surgery were significantly higher in the persistent AF group than in the control group (P < 0.01). The successful surgery group had distinctly lower BNP levels before ablation than the recurrent group (P < 0.01). In the recurrent group, BNP levels 2 h after ablation were significantly lower than those be-fore ablation (P < 0.01); these levels increased after AF recurrence (P < 0.01) and were comparable with those before ablation (P < 0.01). Logistic regression analysis indicated that the BNP level was an inde-pendent factor for and predictor of AF recurrence (P < 0.01). The BNP level in patients with persistent AF is clinically important in predicting and evaluating AF recurrence after ablation.

Label-free, real-time detection of the dynamic processes of protein degradation using oblique-incidence reflectivity difference method

Based on the requirements for studying the dynamic process of proteinase action substrates in life science, we selected six random proteins including 1L-10, SCGB2A2, CENPQ, GST, HK1, KLHL7, as well as five different concentrations of 1L-10 proteins of 1 mg/ml, 0.5 mg/ml, 0.25 mg/ml, 0.125 mg/ml, and 0.0625 mg/ml, and fabricated two types of substrate protein microarrays, respectively. We detected the dynamic processes of proteins degraded by proteinase K using oblique-incidence reflectivity difference (OIRD) method in a label-free and real-time manner. We obtained the relevant degradation velocities and the degradation time. The experimental results demonstrate that OIRD has the ability to study proteinase action substrates which is out of reach of label methods and is expected to offer opportunities to determine protease-substrate relationships on the systems biology level.

Association between a single nucleotide polymorphism of the XRCC1 gene and hepatocellular carcinoma susceptibility in the Chinese Han population

The human X-ray repair cross-complementing protein 1 (XRCC1) gene is a potentially gene determining hepatocellular carcinoma (HCC) susceptibility. The purpose of this study was to evaluate the association between XRCC1 and susceptibility to HCC. The association of XRCC1 polymorphisms with HCC susceptibility was investigated in 460 HCC patients and 463 controls using the created restriction site-polymerase chain reaction method. Our results indicate that the c.1471G>A variant could be detected and that the allele and genotype frequencies were statistically different between cases and controls. The AA genotype was strongly associated with increased HCC susceptibility as compared with the GG wild genotype (OR = 2.214, 95%CI = 1.493-3.283, χ(2) = 15.97, P < 0.0001). In addition, significantly increased HCC susceptibility was also found in a dominant and recessive model (P < 0.01). The allele A could contribute to HCC susceptibility compared with the G allele (OR = 1.480, 95%CI = 1.224-1.789, χ(2) = 16.44, P = 0.0001). Results from this study indicate that the XRCC1 c.1471G>A polymorphism is associated with HCC susceptibility in the Chinese Han population. Future studies on larger populations are essential to confirm this association.

Safety and efficacy of intracoronary tirofiban administration in patients with serious thrombus burden and ST-elevation myocardial infarction undergoing percutaneous coronary intervention

OBJECTIVE

This work aims to explore the safety and efficacy of intracoronary tirofiban administration in patients with serious thrombus burden and ST-elevation myocardial infarction (STEMI) undergoing emergency percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

A total of 104 patients with serious thrombus burden and acute STEMI were randomly divided into treatment (intracoronary tirofiban administration, 56 cases) and control (48 cases) groups. Comparison of coronary blood flow, ST-segment resolution (STR), duration of hospital stay, 30-day major adverse cardiac events (MACE) and complications such as hemorrhage was conducted.

RESULTS

In treatment group, the percentage of thrombolysis in myocardial infarction-3 (TIMI-3) flow in the infarct-related artery (IRA) increased (89.3% to 85.4, p < 0.05), blood flow in the IRA calculated with TIMI frame count method enhanced [(1.68 ± 0.23) ml/s to (1.42 ± 0.31) ml/s, p < 0.05], STR on electrocardiogram (ECG) enlarged [(64.3 ± 7.84)% to (48.6 ± 6.47)%, p < 0.05)] and the prevalence of MACE decreased (10.7% to 18.8%, p < 0.05), all of which were significantly different from those of control group, but no statistical difference in complications was observed between two groups (p > 0.05).

CONCLUSIONS

It was simple, safe and effective to perform intracoronary tirofiban administration in patients with serious thrombus burden and STEMI when undergoing emergency PCI.

Regulatory functions of docosahexaenoic acid on ion channels in rat ventricular myocytes

OBJECTIVE

The aim of this study was to study the regulatory functions of docosahexaenoic acid (DHA) on resting potential (RP), action potential duration (APD), delayed rectifier potassium current (Ik), and inwardly rectifier potassium current (Ik1) in rat ventricular myocytes, and analyze the related anti-arrhythmia mechanism.

MATERIALS AND METHODS

Rat ventricular myocytes were isolated by enzyme digestion method. RP, APD, Ik and Ik1 in individual ventricular myocytes were recorded by patch-clamp technique with whole-cell configuration. Effects of DHA with various concentrations (0, 20, 40, 60, 80, 100 and 120 mmol/L, respectively) on RP, AP, Ik and Ik1 were investigated.

RESULTS

There was no statistical difference of RP with different DHA concentrations (p > 0.05, n = 20), and the 25%, 50% and 90% of APD (APD25, APD50, and APD90) were gradually prolonged with increase of DHA concentration, respectively (p < 0.05, n = 20). IK gradually blocked and the I-V curve was downward shifted, according to increase of DHA concentration (p < 0.05, n = 20). The DHA half effect concentration (EC50) was 47.52 ± 2.32 µmol/L. With increasing DHA concentration, the steady-state inactivation curve shifted to left, and the recovery curve shifted to right. DHA had no significant effect on IK1 (p > 0.05, n = 20).

CONCLUSIONS

DHA has regulatory functions on RP, APD, Ik and Ik1 in rat ventricular myocytes, which may be one of the related antiarrhythmic mechanisms.

Low genetic diversity and local adaptive divergence of Dracaena cambodiana (Liliaceae) populations associated with historical population bottlenecks and natural selection: an endangered long-lived tree endemic to Hainan Island, China

Historical population bottlenecks and natural selection have important effects on the current genetic diversity and structure of long-lived trees. Dracaena cambodiana is an endangered, long-lived tree endemic to Hainan Island, China. Our field investigations showed that only 10 populations remain on Hainan Island and that almost all have been seriously isolated and grow in distinct habitats. A considerable amount of genetic variation at the species level, but little variation at the population level, and a high level of genetic differentiation among the populations with limited gene flow in D. cambodiana were detected using inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) analyses. No significant correlation was found between genetic diversity and actual population size, as the genetic diversities were similar regardless of population size. The Mantel test revealed that there was no correlation between genetic and geographic distances among the 10 populations. The UPGMA, PCoA and Bayesian analyses showed that local adaptive divergence has occurred among the D. cambodiana populations, which was further supported by habitat-private fragments. We suggest that the current genetic diversity and population differentiation of D. cambodiana resulted from historical population bottlenecks and natural selection followed by historical isolation. However, the lack of natural regeneration of D. cambodiana indicates that former local adaptations with low genetic diversity may have been genetically weak and are unable to adapt to the current ecological environments.

Serum Levels of Calcitonin Gene-Related Peptide and Substance P are Decreased in Patients with Diabetes Mellitus and Coronary Artery Disease

OBJECTIVE: This study evaluated serum levels of the neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP) in coronary artery disease (CAD) patients with and without a history of diabetes mellitus (DM). METHODS: Patients undergoing coronary angiography for suspected myocardial ischaemia were divided into four groups depending on their clinical status: control group (no CAD or DM; n = 44), DM group (DM without CAD; n = 46), CAD group (stable CAD without DM; n = 44) and DM + CAD group (stable CAD with DM; n = 50). Serum levels of CGRP and SP were determined using radioimmunoassays. RESULTS: CGRP and SP levels in the DM and CAD groups were significantly lower than in the control group. The lowest levels of CGRP and SP were observed in the DM + CAD group. There were no significant differences in CGRP and SP levels between the DM group and the CAD group. CONCLUSION: CGRP and SP may have a role in the pathogenesis of CAD in patients with diabetes.

Up-Regulation of CXC Chemokine Receptor 4 Expression in Chronic Atrial Fibrillation Patients with Mitral Valve Disease May Be Attenuated by Renin–Angiotensin System Blockers

This study characterized CXC chemokine receptor 4 (CXCR4) expression in patients with mitral valve disease and chronic atrial fibrillation (AF). Forty-eight patients with chronic AF formed two groups based on whether they were treated with or without renin–angiotensin system (RAS) blockers (AF + RAS group; n = 25, or AF – RAS group; n = 23). The controls comprised 17 mitral valve disease patients with sinus rhythm (SR group). CXCR4 mRNA and protein levels in the left atria were significantly higher in the AF – RAS and AF + RAS groups than in the SR group. CXCR4 expression was significantly lower in the AF + RAS group than the AF – RAS group. More CD34+ cells expressed CXCR4 in the AF – RAS and AF + RAS groups than in the SR group. Angiotensin II, collagen I and left atrial diameter significantly positively correlated with CXCR4 expression in the AF – RAS group. These results suggest that CXCR4 expression is up-regulated in chronic AF patients with mitral valve disease, is associated with atrial remodelling, and that these effects are attenuated by RAS blockers.

Management of intestinal failure in the pediatric critical care setting

Intestinal failure (IF) is a complex, chronic illness, of increasing importance in the pediatric critical care setting. We can expect an increase in pediatric IF given an increase in the survivors of extreme prematurity and complex congenital heart disease. Overall priorities for management of this condition include surgical and medical strategies to promote intestinal adaptation and to reduce complications, particularly related to malnutrition, liver disease and sepsis. In this review the authors propose that the optimal care for children with IF are multidisciplinary teams abreast of the newest strategies for intestinal rehabilitation. Early listing for intestinal transplantation for children at greatest risk of long-term parenteral nutrition dependency and its life threatening complications is appropriate.

Selective Growth of Vertical-aligned ZnO Nanorod Arrays on Si Substrate by Catalyst-free Thermal Evaporation

By thermal evaporation of pure ZnO powders, high-density vertical-aligned ZnO nanorod arrays with diameter ranged in 80–250 nm were successfully synthesized on Si substrates covered with ZnO seed layers. It was revealed that the morphology, orientation, crystal, and optical quality of the ZnO nanorod arrays highly depend on the crystal quality of ZnO seed layers, which was confirmed by the characterizations of field-emission scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and photoluminescence measurements. For ZnO seed layer with wurtzite structure, the ZnO nanorods grew exactly normal to the substrate with perfect wurtzite structure, strong near-band-edge emission, and neglectable deep-level emission. The nanorods synthesized on the polycrystalline ZnO seed layer presented random orientation, wide diameter, and weak deep-level emission. This article provides a C-free and Au-free method for large-scale synthesis of vertical-aligned ZnO nanorod arrays by controlling the crystal quality of the seed layer.

Angiogenic CXC chemokine expression during differentiation of human mesenchymal stem cells towards the osteoblastic lineage

The potential role of ELR(+) CXC chemokines in early events in bone repair was studied using human mesenchymal stem cells (hMSCs). Inflammation, which occurs in the initial phase of tissue healing in general, is critical to bone repair. Release of cytokines from infiltrating immune cells and injured bone can lead to recruitment of MSCs to the region of repair. CXC chemokines bearing the Glu-Leu-Arg (ELR) motif are also released by inflammatory cells and serve as angiogenic factors stimulating chemotaxis and proliferation of endothelial cells. hMSCs, induced to differentiate with osteogenic medium (OGM) containing ascorbate, beta-glycerophosphate (beta-GP), and dexamethasone (DEX), showed an increase in mRNA and protein secretion of the ELR(+) CXC chemokines CXCL8 and CXCL1. CXCL8 mRNA half-life studies reveal an increase in mRNA stability upon OGM stimulation. Increased expression and secretion is a result of DEX in OGM and is dose-dependent. Inhibition of the glucocorticoid receptor with mifepristone only partially inhibits DEX-stimulated CXCL8 expression indicating both glucocorticoid receptor dependent and independent pathways. Treatment with signal transduction inhibitors demonstrate that this expression is due to activation of the ERK and p38 mitogen-activated protein kinase (MAPK) pathways and is mediated through the G(alphai)-coupled receptors. Angiogenesis assays demonstrate that OGM-stimulated conditioned media containing secreted CXCL8 and CXCL1 can induce angiogenesis of human microvascular endothelial cells in an in vitro Matrigel assay.

Endothelium-independent vasorelaxant effect of puerarin on rat thoracic aorta

To investigate the vasorelaxant effect of puerarin, tension was recorded from rat thoracic aortic rings. Puerarin completely relaxed the contractions induced by phenylephrine (PE) in a concentration-dependent manner in endothelium-intact and endothelium-denuded rat aorta, while had no effect on those preconstricted by a high concentration of potassium chloride (60 mM). Also, puerarin had no effects on the transient contraction elicited by PE or caffeine in Ca2+- free medium. The relaxant effect of puerarin was significantly inhibited by pretreatment of endothelium-denuded aorta with potassium channel antagonists tetraethylammonium and 4-aminopyridine, but not glibenclamide. These results indicate that puerarin induces an endothelium-independent relaxation in rat aortic rings. The mechanisms may involve the reduction in Ca2+ influx through the non-voltage-sensitive calcium channels and the activation of the potassium channels (voltage-activated K+ channels and large conductance Ca2+ -activated K+ channels, but not ATP-sensitive K+ channels).

[Expression of total RNA and amplification of myocardial troponin gene during monitoring viral cardiomyocyte injury.]

BACKGROUND

To investigate the value of circulating cTnI-mRNA detection for monitoring myocardial injury development and prognosis.

METHODS

Viral myocardial injury models in BALB/c mice were created by intraperitoneal inoculation with Coxsackievirus B3 (CVB3,1x108 TCID50) for inducing myocardial injury. The total RNAs were extracted and cTnI-mRNA in mice cardiac tissues and circulating blood were amplified by RT-PCR during mice myocardial injury.

RESULTS

In virus infected mice, the mRNA abundance for cTnI was up-regulated in heart and circulating blood and associated with salient myocardial histopathologic features, including myocardial swelling, inflammatory cell infiltration, pyknosis, karyorrhexis, karyolysis, denaturalization, necrosis, and calcification. The cTnI-mRNA form infected mice heart and circulating cardiac myocytes were analyzed by RT-PCR, the amplified gene fragments were found in all heart tissues. The incidence of cTnI-mRNA was 0, 0, 0, 16.7%, 40.0%, 71.4%, 83.3% and 87.5% in the controls, the 3rd, 6th, 9th, 12th, 15th, 18th,and 21st day in circulating bloods from the infected mice, respectively.

CONCLUSION

The present data suggest that cTnI-mRNA expression is up-regulated and released into blood on viral myocardial injury, and detection of circulating cTnI-mRNA is a sensitive genetic marker for monitoring myocardial injury development and prognosis.

Homocysteine accelerates senescence and reduces proliferation of endothelial progenitor cells

Our previous studies showed that homocysteine (Hcy) reduces endothelial progenitor cell (EPC) numbers and impairs functional activity. However, the mechanisms by which Hcy reduces EPCs numbers and activity remain to be determined. Recent studies have demonstrated that reduced EPCs numbers and activity was associated with EPCs senescence which involved telomerase activity. Therefore, we investigated whether Hcy accelerates the onset of EPCs senescence through telomerase inactivation, leading to cellular dysfunction. EPCs were isolated from peripheral blood and characterized. After ex vivo cultivation, EPCs became senescent as determined by acidic beta-galactosidase staining. Hcy dose-dependently accelerated the onset of EPCs senescence in culture. Moreover, Hcy decreased proliferation of EPCs as assessed by BrdU incorporation assay and colony-forming capacity. To get further insights into the underlying mechanisms of these effects induced by Hcy, we measured telomerase activity and determined the phosphorylation of Akt by using western blot. Hcy significantly diminished telomerase activity and Akt phosphorylation. Taken together, the results of the present study demonstrated that Hcy accelerated the onset of EPCs senescence, leading to cellular dysfunction. The effect of Hcy might be dependent on telomerase inactivation, and Akt dephosphorylation also appeared to play a major role. In addition, atorvastatin had a preventative effect against Hcy-induced EPCs senescence.

SSCP-SNP in pearl millet--a new marker system for comparative genetics

A considerable array of genomic resources are in place in pearl millet, and marker-aided selection is already in use in the public breeding programme at ICRISAT. This paper describes experiments to extend these publicly available resources to a single nucleotide polymorphism (SNP)-based marker system. A new marker system, single-strand conformational polymorphism (SSCP)-SNP, was developed using annotated rice genomic sequences to initially predict the intron-exon borders in millet expressed sequence tags (ESTs) and then to design primers that would amplify across the introns. An adequate supply of millet ESTs was available for us to identify 299 homologues of single-copy rice genes in which the intron positions could be precisely predicted. PCR primers were then designed to amplify approximately 500-bp genomic fragments containing introns. Analysis of these fragments on SSCP gels revealed considerable polymorphism. A detailed DNA sequence analysis of variation at four of the SSCP-SNP loci over a panel of eight inbred genotypes showed complex patterns of variation, with about one SNP or indel (insertion-deletion) every 59 bp in the introns, but considerably fewer in the exons. About two-thirds of the variation was derived from SNPs and one-third from indels. Most haplotypes were detected by SSCP. As a marker system, SSCP-SNP has lower development costs than simple sequence repeats (SSRs), because much of the work is in silico, and similar deployment costs and through-put potential. The rates of polymorphism were lower but useable, with a mean PIC of 0.49 relative to 0.72 for SSRs in our eight inbred genotype panel screen. The major advantage of the system is in comparative applications. Syntenic information can be used to target SSCP-SNP markers to specific chromosomal regions or, conversely, SSCP-SNP markers can be used to unravel detailed syntenic relationships in specific parts of the genome. Finally, a preliminary analysis showed that the millet SSCP-SNP primers amplified in other cereals with a success rate of about 50%. There is also considerable potential to promote SSCP-SNP to a COS (conserved orthologous set) marker system for application across species by more specifically designing primers to precisely match the model genome sequence.

KC chemokine expression by TGF-beta in C3H10T1/2 cells induced towards osteoblasts

The effects of TGF-beta on expression of the platelet-derived growth factor-induced KC protein were explored in mouse mesenchymal C3H10T1/2 and pre-osteoblastic MC3T3-E1 cells to identify a potential role for TGF-beta in expression of angiogenic cytokines during osteogenic differentiation. KC is a member of the CXC chemokine family with homology to human IL-8, a potent neutrophilic chemotactic cytokine. TGF-beta treatment results in increased KC mRNA and protein secretion in C3H10T1/2 induced towards the osteoblastic lineage with all-trans-retinoic acid. This is due to up-regulated transcription rather than enhanced mRNA stability. No induction of KC expression was seen in untreated C3H10T1/2 or MC3T3-E1 upon TGF-beta stimulation. Use of the translational inhibitor cycloheximide results in mRNA "superinduction" suggesting other factors are involved that normally function to down-regulate KC expression. TGF-beta-stimulated conditioned media were a potent chemostimulant for human microvascular endothelial cells (HMEC-1). This activity could be inhibited by pre-incubation with anti-KC neutralizing antibodies.

Effects of homocysteine on number and activity of endothelial progenitor cells from peripheral blood

The aim of this study is to investigate whether homocysteine (Hcy) has influences on endothelial progenitor cells (EPCs) number and activity. Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 d cultured, attached cells were stimulated with Hcy (to make a series of final concentrations: 10, 50, 100 and 200 micromol/l) or vehicle control for the respective time points (6, 12, 24 and 48 h). EPCs were characterized as adherent cells double positive for DiLDL uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating those on fibronectin-coated dishes, and then adherent cells were counted. Incubation of isolated human MNCs with Hcy dose and time dependently decreased the number of EPCs, maximum at 200 micromol/l, 24 h (approximately 50% reduction, P < 0.01). In addition, Hcy dose and time dependently impaired EPC proliferative, migratory, adhesive and in vitro vasculogenesis capacity. In conclusion, hyperHcy may induce the reduction of EPCs with decreased functional activity.

Attempt to adsorb N-nitrosamines in solution by use of zeolites

The strong adsorption of zeolite for N-nitrosamines in solution was first revealed by use of adsorption, and temperature programmed surface reaction (TPSR) techniques. N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) as well as N-nitrosohexamethyleneimine (NHMI) can be adsorbed on zeolite Y, ZSM-5 and A in the solution of methylene chloride or water, which will be helpful for removal of the N-nitrosamines pollution in environmental protection. The equilibrium data were fitted to Freundlich-type isotherms, but the adsorption capacity of zeolites mainly depended on their pore size, surface area and acid-basic properties. Molecular size of adsorbate and solute-solvent interaction also strongly affected the adsorption of N-nitrosamines on zeolite in solution. The extraordinary adsorption properties of NaA zeolite for N-nitrosamines in aqueous solution is first reported and discussed.

Stealth polycyanoacrylate nanoparticles as tumor necrosis factor-alpha carriers: pharmacokinetics and anti-tumor effects

The objective of this study was to investigate the pharmacokinetics and in vivo anti-tumor effect of recombinant human tumor necrosis factor-alpha (rHuTNF-alpha) encapsulated in poly(methoxypolyethyleneglycol cyanoacrylate-co-n-hexadecyl cyanoacrylate) (PEG-PHDCA) nanoparticles. Our experimental results showed that PEG-PHDCA nanoparticles could extend the half-life of rHuTNF-alpha to 7.42 h and obviously change the protein biodistribution in tissues, and in particular, increase accumulation of rHuTNF-alpha in tumor. Compared with PHDCA nanoparticles and free rHuTNF-alpha, PEG-PHDCA nanoparticles loaded with rHuTNF-alpha showed higher antitumor potency at the same dose, which might be related to its higher accumulation in tumor tissues and longer plasma circulation time. Therefore, PEG-PHDCA nanoparticles could be an effective carrier for rHuTNF-alpha.

PEGylated recombinant human tumor necrosis factor alpha: pharmacokinetics and anti-tumor effects

The aim of the present work was to investigate and assess the merit of PEGylated recombinant human tumor necrosis factor-alpha (rHuTNF-alpha) following our previous work. The rHuTNF-alpha was modified using activated polyethylene glycol (PEG), N-succinimidyl succinnate monomethoxy polyethylene glycol (SS-PEG). The pharmacokinetics and anti-tumor effect were investigated. The experimental results showed that PEGylated rHuTNF-alpha could obviously alter in vivo behavioral characteristics of rHuTNF-alpha. Among the synthesized PEG-rHuTNF-alphas with different PEG molecules, PEG20000-rHuTNF-alpha demonstrated the longest circulating half-life (24.8 h) which was about 50 times longer than that of rHuTNF-alpha (28.8 min). In addition, there was much more PEG20000-rHuTNF-alpha distributed into tumor tissues than other PEG-rHuTNF-alphas or rHuTNF-alpha with time, and PEG20000-rHuTNF-alpha also showed the highest anti-tumor potency. These results indicated that PEG20000-rHuTNF-alpha was a useful long circulating molecule with selective localization in tumor tissues and enhanced anti-tumor activity of rHuTNF-alpha.

Insulin and insulin-like growth factor-I promotes angiotensinogen production and growth in vascular smooth muscle cells

BACKGROUND

Circulating insulin and insulin-like growth factor-I (IGF-I) levels are increased in patients with hypertension and insulin resistance. Since both hormones are known to have cell growth-promoting effects, they may contribute to the progression of vascular hypertrophy in patients with insulin resistance. Insulin-mediated activation of the vascular renin-angiotensin system (RAS) stimulates growth in cultured rat vascular smooth muscle cells (VSMC).

OBJECTIVE

In order to evaluate the role of IGF-I-mediated activation of components of the tissue RAS, we examined the effect of IGF-I receptor stimulation on cell proliferation, and production of angiotensinogen in cultured VSMC.

STUDY DESIGN

Aortic VSMC were derived from male Sprague-Dawley rats. IGF-I and insulin-mediated DNA synthesis were estimated by 3H-thymidine uptake (3H-TdR) with or without the angiotensin I converting enzyme inhibitor, captopril. Moreover, angiotensinogen released by the cells to the culture medium was determined by radioimmunoassay with or without the anti-IGF-I receptor antibody alphaIR3 or captopril.

RESULTS

Both IGF-I and insulin increased 3H-TdR uptake by cultured rat VSMC (P < 0.05). Captopril blocked IGF-I and insulin-mediated 3H-TdR uptake (-34.4 +/- 1.9% and -32.7 +/- 1.8%, P < 0.05, respectively). IGF-I increased the angiotensinogen level in the medium by 30.6 +/- 2.9% (P < 0.01). Insulin also stimulated angiotensinogen synthesis by 26.3 +/- 2.2% (P < 0.01). Captopril and alphaIR3 significantly suppressed angiotensinogen production stimulated by both IGF-I and insulin.

CONCLUSIONS

These results indicate that IGF-I as well as insulin stimulates angiotensinogen production and growth in VSMC. Thus, both hormones may independently play a role in progression of the vascular hypertrophy and atherosclerosis in patients with hypertension and insulin resistance through activation of the tissue RAS.

Prenatal heroin exposure. Effects on development, acoustic startle response, and locomotion in weanling rats

The purpose of this study was to investigate the effects of prenatal heroin exposure on the offspring in postnatal behavioral development. Pregnant Sprague-Dawley rats were injected daily (s.c.) with 10mg/kg of heroin from gestational day 8 to 20. The control dam received saline injections and the pair-fed dam received saline and was yoked to a weight-matched heroin-treated dam. Litters were culled to eight to ten pups and weighed at postnatal day (PND) 1, 8, 15, and 22. Acoustic prepulse inhibition and habituation were parameters used for evaluating the sensorimotor gating and simple form of learning respectively. Locomotor activity and rearing were assessed using the photobeam activity system. All behavioral tests were performed on the offspring at PND 21 to 23. Results showed that heroin treatment significantly reduced maternal food intake, water consumption, and weight gain. Both heroin-exposed and pair-fed groups showed a marked reduction in birth weight in both male and female pups when compared with controls; however the postnatal weight gain in heroin-exposed pups was significantly lower than the pair-fed group by 3 weeks postnatally, particularly in the female pups. These female pups also showed a significant increase in ambulation and rearing when compared to the pair-fed pups. The habituation rate in both types of behavioral tests was also decreased in these female pups as compared to control and pair-fed groups. The present study indicated that prenatal heroin exposure could result in a marked retardation of postnatal development and learning. These effects are sex related.

Preparation of biodegradable microspheres of testosterone with poly(D,L-lactide-co-glycolide) and test of drug release in vitro

Biodegradable microspheres formulation of testosterone (T) can be used as a new physiological approach for androgen replacement in hypogonadal men. In this study, poly(D,L-lactide-co-glycolide) (PLGA) microspheres containing T were prepared by a solvent-evaporation/solvent-diffusion process and the drug release tests of the microspheres were carried out in vitro. T/PLGA microspheres with good yield, desired size and satisfied drug loading were obtained. A significant testosterone sustained release was shown in the drug release tests in vitro. Since PLGA microspheres preparations are normally sterilized by colbat-60 irradiation, the effects of 25 kGy colbat-60 irradiation on physicochemical properties and in vitro drug release profile of T/PLGA microsphere were investigated. The results showed that the irradiation didn't have any effects on the physicochemical properties of T. Though about one-third decrease in molecular weight of PLGA was caused by the irradiation, no significant changes were observed on the drug release profile in vitro.

The unvalidity of Kohlrausch' regulating function for Svensson's isoelectric focusing and stationary electrolysis at steady state

Kohlrausch' regulating function is of important significance in the field of electrophoresis. In this paper, the relative regulating function is defined from Kohlrausch' regulating function. The relative values, including the limited values, of the regulating function for the stationary electrolysis of salt, on which the classic isoelectric focusing (IEF) is based, are computed and compared with the computer program of the QBASIC written by us. The results directly demonstrate that, (1) in a few cases the regulating function is valid for the stationary electrolysis and IEF, whereas (2) the function is, in most of cases, not valid for the stationary electrolysis and IEF at steady-state. Those findings may be useful for the studies on the relationships between Kohlrausch' regulating function and IEF and for the classification of numerous electrophoretic techniques.

Mechanism of hexosamine-induced insulin resistance in transgenic mice overexpressing glutamine:fructose-6-phosphate amidotransferase: decreased glucose transporter GLUT4 translocation and reversal by treatment with thiazolidinedione

Hexosamines have been hypothesized to mediate aspects of glucose sensing and toxic effects of hyperglycemia. For example, insulin resistance results when the rate-limiting enzyme for hexosamine synthesis, glutamine:fructose-6-phosphate amidotransferase (GFA), is overexpressed in muscle and adipose tissue of transgenic mice. The glucose infusion rates required to maintain euglycemia at insulin infusion rates of 0.5, 2, 15, and 20 mU/kg x min were 39-90% lower in such transgenic mice, compared with their control littermates (P < or = 0.01). No differences were observed in hepatic glucose output, serum insulin levels, or muscle ATP levels. Uptake of 2-deoxyglucose, measured under conditions of hyperinsulinemia, was significantly lower in transgenic hindlimb muscle, compared with controls (85.9 +/- 17.8 vs. 166.8 +/- 15.1 pmol deoxyglucose/g x min). The decrease in glucose uptake by transgenic muscle was associated with a disruption in the translocation of the insulin-stimulated glucose transporter GLUT4. Fractionation of muscle membranes on a discontinuous sucrose gradient revealed that insulin stimulation of control muscle led to a 28.8% increase in GLUT4 content in the 25% fraction and a 61.2% decrease in the 35% fraction. In transgenic muscle, the insulin-stimulated shifts in GLUT4 distribution were inhibited by over 70%. Treatment of the transgenic animals with the thiazolidinedione troglitazone completely reversed the defect in glucose disposal without changing GFA activity or the levels of uridine 5'-diphosphate-N-acetylglucosamine. Overexpression of GFA in skeletal muscle thus leads to defects in glucose transport similar to those seen in type 2 diabetes. These data support the hypothesis that excess glucose metabolism through the hexosamine pathway may be responsible for the diminished insulin sensitivity and defective glucose uptake that are seen with hyperglycemia.

Towards rice genome scanning by map-based AFLP fingerprinting

Map-based DNA fingerprinting with AFLP markers provides a fast method for scanning the rice genome. Three hundred AFLP markers identified with ten primer combinations were mapped in two rice populations. The genetic maps were aligned and almost full coverage of the rice genome was obtained. The transferability of AFLP markers between indica x japonica and indica x indica crosses was tested. The chromosomes were divided into DNA Fingerprint Linkage Blocks (DFLBs) defined by specific AFLP markers. Using these blocks, the degree of similarity or divergence within specific chromosome regions was calculated for nine varieties. Applications of map-based fingerprinting for biodiversity studies and maker-assisted selection are discussed.

Erythropoietin upregulates angiotensin receptors in cultured rat vascular smooth muscle cells

OBJECTIVE

Plasma renin is not elevated in recombinant human erythropoietin (rhEPO)-induced hypertension but angiotensin converting enzyme inhibitors reduce blood pressure in both human and animal studies. Since rhEPO elevates renin and angiotensinogen messenger RNAs in angiotensin II target tissues such as the aorta, we explored the actions of rhEPO on renin-angiotensin system-related gene transcription of cultured rat vascular smooth muscle cells.

DESIGN AND METHODS

To separate direct actions of rhEPO from those mediated secondarily by potential activation of the renin-angiotensin system, vascular smooth muscle cells were cultured with rhEPO and enalapril to inhibit the angiotensin converting enzyme and losartan to inhibit angiotensin II type 1 receptors.

RESULTS

Vascular smooth muscle cells cultured with rhEPO (6-8 units/ml) demonstrated elevations (40-120%) in messenger RNAs of the renin-angiotensin system (renin, angiotensinogen, angiotensin receptor types 1 and 2) and increased levels of several messenger RNAs known to respond to angiotensin II (transforming growth factor-beta, insulin-like growth factor-II, epidermal growth factor, c-fos and platelet-derived growth factor). In contrast, cells cultured in the presence of rhEPO and enalapril or losartan showed elevations of messenger RNA for only the two types of angiotensin II receptor. This increase was higher than that obtained when cells were cultured with rhEPO or either antagonist alone. The increase in specific binding of angiotensin II to cells cultured in the presence of rhEPO and enalapril or rhEPO and losartan paralleled the changes in receptor messenger RNA.

CONCLUSIONS

rhEPO exerts its primary action on vascular smooth muscle cells via an increase in angiotensin receptor messenger RNA, resulting in a parallel increase in angiotensin II receptor expression. We suggest that increased receptor expression secondarily mediates the expression of other renin-angiotensin system messenger RNAs, which leads to angiotensin II-responsive gene transcription. The elevation in angiotensin II receptors, as observed in response to rhEPO, may provide a mechanism by which other forms of renin-dependent hypertension are initiated.

Insulin-mediated growth in aortic smooth muscle and the vascular renin-angiotensin system

Insulin has been shown to directly affect blood vessel tone and to promote vascular hypertrophy, but the mechanism of these actions remains uncertain. Because angiotensin I (Ang I)-converting enzyme inhibitors have been shown to improve insulin action and to impede the progression of vascular hypertrophy in hypertensive animal models, it is possible that the vascular properties of insulin may be mediated through the tissue renin-angiotensin system (RAS). To evaluate this relationship, we first investigated the effect of insulin on components of the RAS using cultured rat vascular smooth muscle cells (VSMCs). Insulin treatment (1000 microU/mL) markedly increased angiotensinogen mRNA expression and angiotensinogen production. We next investigated the role of the RAS in insulin-mediated cell proliferation, using [3H]thymidine uptake. Studies were done both with insulin alone and in the presence of captopril (1x10(-7) to 10(-5) mol/L) and losartan (1x10(-9) to 10(-7) mol/L). [3H]Thymidine uptake was increased significantly by 1000 microU/mL insulin, and this stimulation was reduced by 1x10(-6) mol/L captopril (-38.8%, P<0.05) and by 1x10(-8) mol/L losartan (-37. 5%, P<0.05). Further studies showed that the degree of insulin-mediated [3H]thymidine uptake in VSMCs could be duplicated by 4x10(-10) mol/L Ang II. Losartan reduced the effects of both Ang II and insulin on [3H]thymidine uptake by about 40% to 45% of baseline (P<0.05). Captopril reduced insulin-mediated [3H]thymidine uptake but did not affect Ang II-mediated [3H]thymidine uptake. In summary, insulin induced significant stimulation of angiotensinogen expression and production and stimulated growth similar to that seen with Ang II in cultured rat VSMCs. Inhibition of Ang II production or its binding to the Ang II type 1 (AT1) receptor inhibited insulin-mediated growth in a fashion similar to that seen with inhibition of Ang II-mediated growth. Thus, insulin can modulate the vascular RAS, and the effect of insulin on vascular growth may be via direct effects on angiotensinogen expression and translation operative through both the AT1 receptor and the conversion of Ang I to Ang II.

Evidence for defects in the trafficking and translocation of GLUT4 glucose transporters in skeletal muscle as a cause of human insulin resistance

Insulin resistance is instrumental in the pathogenesis of type 2 diabetes mellitus and the Insulin Resistance Syndrome. While insulin resistance involves decreased glucose transport activity in skeletal muscle, its molecular basis is unknown. Since muscle GLUT4 glucose transporter levels are normal in type 2 diabetes, we have tested the hypothesis that insulin resistance is due to impaired translocation of intracellular GLUT4 to sarcolemma. Both insulin-sensitive and insulin-resistant nondiabetic subgroups were studied, in addition to type 2 diabetic patients. Biopsies were obtained from basal and insulin-stimulated muscle, and membranes were subfractionated on discontinuous sucrose density gradients to equilibrium or under nonequilibrium conditions after a shortened centrifugation time. In equilibrium fractions from basal muscle, GLUT4 was decreased by 25-29% in both 25 and 28% sucrose density fractions and increased twofold in both the 32% sucrose fraction and bottom pellet in diabetics compared with insulin-sensitive controls, without any differences in membrane markers (phospholemman, phosphalamban, dihydropyridine-binding complex alpha-1 subunit). Thus, insulin resistance was associated with redistribution of GLUT4 to denser membrane vesicles. No effects of insulin stimulation on GLUT4 localization were observed. In non-equilibrium fractions, insulin led to small GLUT4 decrements in the 25 and 28% sucrose fractions and increased GLUT4 in the 32% sucrose fraction by 2.8-fold over basal in insulin-sensitive but only by 1.5-fold in both insulin-resistant and diabetic subgroups. The GLUT4 increments in the 32% sucrose fraction were correlated with maximal in vivo glucose disposal rates (r = +0.51, P = 0.026), and, therefore, represented GLUT4 recruitment to sarcolemma or a quantitative marker for this process. Similar to GLUT4, the insulin-regulated aminopeptidase (vp165) was redistributed to a dense membrane compartment and did not translocate in response to insulin in insulin-resistant subgroups. In conclusion, insulin alters the subcellular localization of GLUT4 vesicles in human muscle, and this effect is impaired equally in insulin-resistant subjects with and without diabetes. This translocation defect is associated with abnormal accumulation of GLUT4 in a dense membrane compartment demonstrable in basal muscle. We have previously observed a similar pattern of defects causing insulin resistance in human adipocytes. Based on these data, we propose that human insulin resistance involves a defect in GLUT4 traffic and targeting leading to accumulation in a dense membrane compartment from which insulin is unable to recruit GLUT4 to the cell surface.