[Diagnostic performance of a novel Mycobacterium Tuberculosis specific T-Cell based assay for tuberculosis].

Objective: To evaluate the diagnosic performance of a novel Mycobacterium tuberculosis (MTB) specific T-cell based assay for tuberculosis, which targets the mRNA detection of interferon gamma-induced protein 10 (IP-10). Methods: Suspected tuberculosis patients were prospectively and consecutively recruited in Beijing Chest Hospital between March 2018 and November 2019, and individuals with lower risk of MTB infection were also recruited. IP-10.TB and T-SPOT.TB assays were simulataneously performed on peripheral blood samples. The diagnostic performance of IP-10.TB and T-SPOT.TB were analyzed using the receiver operating characteristic curve. Accordance of IP-10.TB and T-SPOT.TB was analyzed by Cohen's kappa test, while the correlation between the expression level of IP-10 mRNA in IP-10.TB test and the number of SFCs in T-SPOT.TB test were analyzed by Pearson correlation test. Results: A total of 235 patients with tuberculosis, 110 patients with other diseases and 153 individuals with lower risk of MTB infection were included in the final analysis. No significant difference was detected in the rate of indeterminate results between IP-10.TB assay (3/498, 0.60%) and T-SPOT.TB assay (6/498, 1.21%). The total sensitivity and specificity of IP-10.TB assay were 91.3% (95%CI 86.8%-94.6%) and 81.1% (95%CI 75.8%-85.7%). The specificity of IP-10.TB in individuals with lower risk of MTB infection was 98.0% (95%CI 94.4%-99.6%). The total sensitivity and specificity of T-SPOT.TB assay were 93.0% (95%CI 88.9%-96.0%) and 83.8% (95%CI 78.7%-88.1%). The specificity of T-SPOT.TB in individuals with lower risk of MTB infection was 100% (95%CI 97.6%-100.0%). No significant differences were detected in sensitivity and specificity between IP-10.TB and T-SPOT.TB assays (P>0.05). The positive coincidence rate of these 2 methods was 91.0% (95%CI 87.5%-94.5%), and the negative coincidence rate was 88.9% (95%CI 84.9%-92.9%) and the total coincidence rate was 90.0% (95%CI 87.3%-92.6%). The Cohen's kappa value was 0.80 (95%CI 0.75-0.85, P<0.001) between IP-10.TB and T-SPOT.TB assays. Conclusion: These results showed that the diagnostic performance of IP-10.TB was consistent with that in T-SPOT.TB, and this test could be a novel adjunctive tool for the diagnosis of tuberculosis.

[Impact of systolic blood pressure on outcome of patients with nonvalvular atrial fibrillation].

Objective: To investigate the impact of different levels of systolic blood pressure on all-cause, cardiovascular and cerebrovascular mortality in patients with nonvalvular atrial fibrillation (AF). Methods: This is a prospective cohort study. Patients with AF or atrial flutter diagnosed by 12 lead electrocardiogram during physical examination of Kailuan Group employees from July 2006 to December 2017 or previously diagnosed with AF in an inpatient setting at a level 2A hospital or above were eligible for the study. Baseline clinical characteristics including age, gender, systolic blood pressure were collected. According to the level of systolic blood pressure, patients were divided into systolic blood pressure<120 mmHg (1 mmHg=0.133 kPa)group, 120 mmHg ≤ systolic blood pressure<140 mmHg group, and systolic blood pressure ≥140 mmHg group. The time of first diagnosis with AF was defined as the start of follow-up and the final follow-up ended at December 2018. Primary endpoint was all-cause death. Related information was obtained through the social security system or inpatient medical records. The cause of death was defined according to the International Classification of Diseases disease (ICD-10) codes by professional medical stuffs. Multifactorial Cox proportional risk model was used to analyze the relative risk ratios for the occurrence of death in different systolic blood pressure level groups. The relationship between systolic blood pressure levels and mortality in the patients with AF was analyzed by using natural spline function curves. Results: A total of 1 721 patients with AF were enrolled (average age=(67.0±9.0) years), patients were followed up for (6.3±3.8) years. 544 out of 1 721 patients with AF died during the follow-up period (31.61%). The cumulative incidence rate of all-cause mortality, cardiovascular and cerebrovascular death was 26.13%, 25.59%, 36.96% and 14.86%, 11.87%, 19.76% respectively in the systolic blood pressure<120 mmHg, 120 mmHg ≤ systolic blood pressure<140 mmHg and systolic blood pressure ≥140 mmHg groups. The cumulative incidence rate of all-cause, cardiovascular and cerebrovascular death was significantly higher in the group with systolic blood pressure ≥140 mmHg than in 120 mmHg ≤ systolic blood pressure<140 mmHg group (P<0.05). Compared with 120 mmHg ≤ systolic blood pressure<140 mmHg group, multivariable Cox proportional hazards regression models showed that the HRs (95%CI) for all-cause, cardiovascular and cerebrovascular death were 1.47 (1.20 to 1.79) and 1.69 (1.27 to 2.26) for the group with systolic blood pressure ≥ 140 mmHg (P<0.05). In contrast, the HRs (95%CI) for all-cause, cardiovascular and cerebrovascular death in the systolic blood pressure<120 mmHg group were 0.99 (0.73-1.35) and 1.24 (0.82-1.89), respectively, with no statistically significant differences between the two groups (P>0.05). The natural spline curve showed that there was a "U" relationship between systolic blood pressure levels and all cause death and cardiovascular and cerebrovascular death in this patient cohort. Systolic blood pressure greater than or less than 123 mmHg was associated with increased risk of death of AF patients in this cohort. Conclusion: Compared with systolic blood pressure<120 mmHg and systolic blood pressure≥140 mmHg group, the risk of all-cause and cardiovascular and cerebrovascular death is the lowest in AF patients with 120 mmHg ≤ systolic blood pressure<140 mmHg in this cohort.

A simple model for transit dosimetry based on a water equivalent EPID.

PURPOSE: The aim of this study was to demonstrate a new model for implementing a transit dosimetry system as a means of in vivo dose verification with a water equivalent electronic portal imaging device (WE-EPID) and a conventional treatment planning system (TPS). METHOD AND MATERIALS: A standard amorphous silicon (a-Si) EPID was modified to a WE-EPID configuration by replacing the metal-plate/phosphor screen situated above the photodiode detector with a 3 cm thick water equivalent plastic x ray converter material. A clinical TPS was used to calculate dose to the WE-EPID in its conventional EPID position behind the phantom/patient. The "extended phantom" concept was used to facilitate dose calculation at the EPID position, which is outside the CT field of view (FOV). The CT images were manipulated from 512 × 512 into 1024 × 1024 and padded pixels were assigned the density of air before importing to the TPS. The virtual WE-EPID was added as an RT structure of water density at the EPID plane. The accuracy of TPS dose calculations at the EPID plane in transit geometry was first evaluated for different field sizes and thickness of object in the beam by comparison with the dose measured using a 2D ion chamber array (ICA) and the WE-EPID. Following basic dose response tests, clinical fields including direct single fields (open and wedged) and modulated fields (integrated or control point by control point doses for VMAT) were measured for 6 MV photons with varying of solid water thickness or an anthropomorphic phantom present in beam. The EPID images were corrected for dark signal and pixel sensitivity and converted to dose using a single dose calibration factor. The 2D dose evaluation was conducted using 3%/3 and 2%/2 mm gamma-index criteria. RESULTS: The measured dose-response with the ICA and WE-EPID for all basic dose-response tests agreed with TPS dose calculations to within 1.5%. The maximum difference in dose profiles for the largest measured field size of 25 × 25 cm2 was 2.5%. Gamma evaluation showed at least 94% (3%/3 mm criteria) and 90% (2%/2 mm) agreement in both integrated and control-point doses for all clinical fields acquired by the WE-EPID and ICA when compared with TPS-calculated portal dose images. CONCLUSION: A new approach to transit dose verification has been demonstrated utilizing a water equivalent EPID and a commercial TPS. The accuracy of dose calculations at the EPID plane using a commercial TPS beam model was experimentally confirmed. The model proposed in this study provides an accurate method to directly verify doses delivered during treatment without the additional uncertainties inherent in modelling the complex dose-response of standard EPIDs.

[Association between the cardiovascular health score and new-onset atrial fibrillation].

OBJECTIVE: To observe the association between the cardiovascular health score and new-onset atrial fibrillation. METHODS: A total of 95 026 participants who participated the health examination between July 2006 and October 2007 at Kailuan group and without history of atrial fibrillation were selected as the observation cohort. The second, the third and the fourth health examination were performed between July 2008 to October 2009, July 2010 to October 2011, July 2012 to October 2013, respectively.A total of 85 028 participants were included in the final analysis after excluding participants who had new-onset valvular atrial fibrillation and participants lost to follow-up. The participants were divided into 4 subgroups by cardiovascular health score at baseline according to the definition of AHA and cardiovascular health scoring system, namely group of 0-6 points (n=11 103), 7-8 points (n=24 487), 9-10 points (n=32 556), and 11-14 points (n=16 882). The incidence of atrial fibrillation in each subgroup was observed, and the association between cardiovascular health score and risk of new-onset atrial fibrillation was analyzed using multiple Cox regression analysis. RESULTS: A total of 254 participants developed atrial fibrillation during the median of (5.6±1.4) years follow-up. The total incidence of new-onset atrial fibrillation was 0.53/1 000 person-year. The incidence of atrial fibrillation was 0.69/1 000 person-year, 0.60/1 000 person-year, 0.56/1 000 person-year, and 0.30/1 000 person-year, respectively in 0-6 points, 7-8 points, 9-10 points, and 11-14 points subgroups, respectively(P<0.01). After adjustment of age, gender, education level, income, drink, history of myocardial infarction, history of stroke, serum uric acid and C reactive protein level, multiple Cox regression analysis showed that one health score point increase was related to 8% reduction of new onset atrial fibrillation(HR=0.92, 95%CI 0.86-0.99, P<0.05). Compared with the group of 0-6 points group, the risk of atrial fibrillation in the group of 11-14 points group was reduced by 49% (HR=0.51, 95%CI 0.31-0.83, P<0.01). CONCLUSION: The risk of new-onset atrial fibrillation is reduced in proportion to increase of cardiovascular health score. Clinical Trail Registry: Chinese Clinical Trail Registry, ChiCTR-TNRC-11001489.

[Impact of combined systolic blood pressure and body mass index on the risk of new-onset atrial fibrillation].

OBJECTIVE: To observe the impact of combined systolic blood pressure and body mass index (BMI) on the risk of new-onset atrial fibrillation. METHODS: The participants who participated the health examination between July 2006 and October 2007 at Kailuan medical group and had no history of atrial fibrillation were selected as the observation cohort.The second, the third and the fourth health examination were conducted between July 2008 and October 2009, July 2010 and October 2011, July 2012 and October 2013, respectively.The participants were stratified by 3 systolic blood pressure levels (≤120, 120-140, ≥140 mmHg (1 mmHg=0.133 kPa))×3 BMI levels (≤24, 24-28, ≥28 kg/m(2)) at baseline.The combined effect of systolic blood pressure and BMI on the risk of new-onset atrial fibrillation was analyzed by multiple Cox regression analysis. RESULTS: A total of 99 206 participants were recruited and 88 715 participants were included in the final analysis after excluding participants who had new-onset valvular atrial fibrillation or lost to follow-up.A total of 265 participants developed atrial fibrillation during the 5.6 years follow-up.The incidence of atrial fibrillation increased with the BMI and systolic blood pressure, the incidence of new onset of atrial fibrillation was significantly higher in the group with systolic blood pressure≥140 mmHg and BMI≥28 kg/m(2) than the group with systolic blood pressure≤120 mmHg and BMI≤24 kg/m(2)(1.15/1 000 person-year vs. 0.25/1 000 person-year). Multiple Cox regression analysis showed that participants in the group with systolic blood pressure≥140 mmHg and BMI≥28 kg/m(2) carried 2.08 (95%CI 1.18-3.67) times higher risk for atrial fibrillation than the group with systolic blood pressure≤120 mmHg and BMI≤24 kg/m(2) after adjustment for age, gender and other confounders at baseline. CONCLUSION: Participants with systolic blood pressure≥140 mmHg and BMI≥28 kg/m(2) are at high risk for new onset of atrial fibrillation.

Diagnosis of latent tuberculosis by ELISPOT assay and tuberculin skin test.

OBJECTIVE: To determine the prevalence of latent tuberculosis infection (LTBI) in college students. PATIENTS AND METHODS: Four hundred and twenty newly admitted college students were enrolled. The Enzyme-Linked ImmunoSpot assay (ELISPOT) was used. Overall, 171 students with ELISPOT assay+/TST+ were monitored for three years to detect active TB disease. RESULTS: The overall positive rate of ELISPOT assay was 40.7% among TST+ students. The ELISPOT positive rates were 36.9%, 45.4%, and 64.3% in groups of TST induration of 10-14mm, 15-20mm, and ≥20mm, respectively, with a significant difference (χ(2)=10.136, P<0.01) but no significant difference between BCG scar and no scar (41.2% vs. 38.8%; P>0.05). None of the 171 untreated students contracted active TB within the three-year monitoring period. CONCLUSION: The LTBI rate might be overestimated by TST compared with interferon-γ release assays. On the basis of a close monitoring, few students developed active TB despite a positive result to the TST and ELISPOT assay.

Selective termination in discordant twin pregnancy with early onset preeclampsia: case report.

OBJECTIVE: To study the effectiveness of selective termination for discordant twins in treating early onset preeclampsia. MATERIALS AND METHODS: After literature review, ethical review, and discussion with the couple, one patient with early onset preeclampsia complicated with a lethal condition in one twin, was performed selective termination by intracardiac injection of potassium chloride at 27 weeks' and four days' gestation in an effort to reverse preeclampsia and prolong the pregnancy. RESULTS: The clinical manifestation of preeclampsia was alleviated in this patient. At 29 weeks, the stillborn fetus was delivered because of spontaneous preterm labor. A live birth was achieved five days later. All procedures allowed continuation of the pregnancy for an additional two weeks and one day of the remaining fetus. CONCLUSION: Selective termination may be an option for treating early onset preeclampsia in discordant twins, instead of termination of whole pregnancy.

Oxidative stress markers in intrahepatic cholestasis of pregnancy: a prospective controlled study.

OBJECTIVE: Intrahepatic cholestasis of pregnancy (ICP), characterized by skin pruritus and elevation of serum aminotransferase activity and bile acid concentration in the mother, is one of the most common liver disorders in pregnancy. It was proved that ICP might lead to fetal distress by triggering oxidative damage. Total bile acids (TBA) are an established marker for assessment of the severity of ICP. The aim of this study was to explore associations of TBA levels with levels of the oxidative stress markers 8-epimer of prostaglandin F2alpha (8-iso-PGF2α), superoxide dismutase (SOD) and glutathione peroxidase (Gpx) in ICP. PATIENTS AND METHODS: Maternal plasma levels of 8-iso-PGF2α, SOD and Gpx were examined in ICP patients (n=40) and normal pregnancy controls (n=47) using an enzyme-linked immunosorbent assay (ELISA) analysis. RESULTS: Plasma levels of 8-iso-PGF2α and Gpx were significantly lower in ICP patients than in controls (p = 0.006 and 0.002, respectively), while no significant difference was observed in SOD levels between the two groups. Levels of 8-iso-PGF2α and TBA were negatively correlated (r = -0.277, p = 0.01, Spearman's correlation coefficient). CONCLUSIONS: The clinical severity of ICP is closely related to the degree of lipid peroxidation, and the natural antioxidant system might fail to work effectively in the presence of lipid peroxidation damage in ICP.

High risk factors of atrial fibrillation in type 2 diabetes: results from the Chinese Kailuan study.

BACKGROUND: The pathophysiological mechanisms for atrial fibrillation (AF) vulnerability in diabetic patients are largely unclear. AIM: To investigate the high risk factors of AF in Chinese Kailuan diabetes. DESIGN: A retrospective review of AF in Chinese Kailuan diabetes. METHODS: Research and statistic analysis on the clinical data of 9050 diabetic patients from Kailuan Coal Mine Group Corporation who participated in a health survey from July 2006 to October 2007. RESULTS: Sixty diabetic patients (50 males and 10 females) were diagnosed with AF during the health checkup, with a prevalence of 0.66% (0.67% in males and 0.62% in females). Univariate analysis showed that patients with AF were older and had higher levels of serum uric acid (UA), pulse pressure, serum c-reactive protein and anti-hypertensive medication usage, but lower levels of fasting blood glucose and triglycerides (TG). Multivariate analysis indicated that older age (OR = 1.09; 95% CI: 1.06-1.12), increased UA (OR = 1.01; 95% CI: 1.00-1.01) and decreased TG (OR = 0.71; 95% CI: 0.55-0.92) were independent predictive factors of AF after adjusting for other variables. After gender stratification, age and UA remained as independent predictive factors of AF in both male and female patients. However, TG had an independent inverse association with AF in male patients only. CONCLUSIONS: Age and UA are independent predictive factors of AF in both male and female diabetic patients. TG is inversely correlated with AF in male diabetic patients only.

Inadequate values from an interferon-gamma release assay for smear-negative tuberculosis in a high-burden setting.

OBJECTIVE: To examine the usefulness of an interferon-gamma release assay (IGRA) for the diagnosis of smear-negative tuberculosis (TB) in China. DESIGN: A total of 624 patients with presumed pulmonary TB were enrolled prospectively and categorised as smear-negative TB, smear-positive TB or no TB. All patients were tested using T-SPOT.TB. RESULTS: Both the smear-negative and smear-positive TB groups had significantly more spot-forming cells (SFCs) than the no TB group (all P < 0.001), while the smear-negative group had fewer SFCs than the smear-positive TB group (P < 0.001). The specificity of T-SPOT.TB was 60.4% (95%CI 53.4-67.1). The sensitivities of T-SPOT.TB in the smear-negative and smear-positive TB groups were respectively 81.4% (95%CI 75.7-86.0) and 93.2% (95%CI 87.6-96.4). The sensitivity in the smear-negative TB group was much lower than that in the smear-positive TB (P < 0.05). CONCLUSIONS: The sensitivity of T-SPOT.TB was lower due the paucibacillary nature of the samples, and the specificity was lower due to the high prevalence of latent tuberculous infection in the smear-negative TB patients. The T-SPOT.TB test should only be used as a supplementary test and not as a single test to rule in or rule out smear-negative TB.

Molecular regulation of organic anion transporting polypeptide 1A2 (OATP1A2)by taurocholic acid in Bewo Cells.

To characterize the mechanisms of action of taurocholic acid(TCA) and farnesoid X receptor(FXR) on organic anion transporting polypeptide 1A2(OATP1A2) expression in placental Bewo cell line. Quantitative real-time PCR and Western blots were used to detect OATP1A2 in Bewo cells cultured with TCA and pcDNA3.1(+)-hFXR transfected Bewo cells after incubation with 2 mM TCA for 48 hours. TCA(0.02 mM) induced the mRNA and protein expression of OATP1A2 by 3 and 1.6 fold (p<0.05), respectively, while 0.2 and 2 mM TCA induced mRNA and protein expression by 1.5 and 1.3 fold, respectively. The concentration of TCA was negatively correlated with OATP1A2 gene expression (P<0.05). In pcDNA3.1(+)-hFXR transfected Bewo cells with 2 mM TCA demonstrated a 2-3 fold increase in OATP1A2 over controls (P<0.05). TCA is one of the regulation factors for OATP1A2 in the Bewo cell line. A low dose of TCA can induce fetal membrane expression of OATP1A2. This may present a physiological or compensatory mechanism of the placenta, while the high dose of TCA may produce a pathological or pathogenic mechanism. Farnesoid X receptor may act in synergy with TCA to increase the expression of OATP1A2. This may be a treatment strategy for fetal cholestasis.

NOD1 expression elicited by iE-DAP in first trimester human trophoblast cells and its potential role in infection-associated inflammation.

OBJECTIVES: The underlying mechanisms of protective immunity of placental trophoblast cells against bacterial infection remain largely unknown. NOD1 are intracellular pattern recognition receptors that are activated by bacterial peptides and mediate innate immunity. This study aimed to investigate the expression and function of NOD1 in first trimester trophoblast cells, and evaluate the potential role of trophoblast cells in infection-associated inflammation. STUDY DESIGN: Human extravillous trophoblast cell line HTR8 cells were stimulated with various concentrations of iE-DAP for various periods of time. NOD1 expression was detected by immunofluorescence, and the changes in NOD1 and RICK mRNA and protein in H8 cells were determined by real-time polymerase chain reaction and Western blot analysis. The concentrations of interleukin (IL)-8 and IL-6 secreted by H8 cells were examined by enzyme-linked immunosorbent assay. NF-κB transcription activity and P65 expression were detected by electrophoretic mobility shift assay and Western blot analysis. RESULTS: H8 cells expressed NOD1, and the effects of iE-DAP on NOD1 were dose- and time-dependent. The concentration of IL-8 increased gradually with increasing concentration of iE-DAP, and the levels of IL-8 and IL-6 were associated with the duration of exposure to iE-DAP. The dose of iE-DAP was significantly associated with expression of RICK and P65, and stimulation of H8 cells by iE-DAP altered NF-κB transcription activity. CONCLUSIONS: NOD1 may have a role in mediating infection-associated inflammation. Once iE-DAP is recognized by NOD1, the inflammatory response may be induced via NOD1-RICK-NF-κB-mediated pathways.

The molecular mechanism of microRNA-145 to suppress invasion-metastasis cascade in gastric cancer.

Invasion and metastasis are the major features of malignant tumors that are responsible for 90% of cancer-related deaths. Recently, microRNAs have been discovered to have a role in suppressing tumor metastasis. This study's aim was to clarify the roles of miR-145 in gastric carcinomas and its underlying molecular mechanism in regulating tumor metastasis. Here, we demonstrate a stepwise downregulation of miR-145 level in nontumorous gastric mucosa, primary gastric cancers and their secondary metastases. In vitro analysis of miR-145's ectopic expression and loss-of-function suggests that it suppresses gastric cancer cell migration and invasion. In vivo spontaneous metastasis and experimental metastasis assay further confirm its function in suppressing the invasion-metastasis cascade, including impairing local invasion and inhibiting hematogenous metastasis in gastric cancers. Furthermore, we identified a novel mechanism of miR-145 to suppress metastasis. N-cadherin (CDH2) was proved to be a direct target of miR-145, using luciferase assay and western blot. Re-expressing N-cadherin in miR-145-transfected cells reverses their migration and invasion defects. Although not a direct target of miR-145, matrix metallopeptidase 9 (MMP9), but not MMP2, was also significantly decreased in miR-145-expressing cells. We suggest that miR-145 suppresses tumor metastasis by inhibiting N-cadherin protein translation, and then indirectly downregulates its downstream effector MMP9.

Design and synthesis of potent and selective inhibitors of integrin VLA-4.

The synthesis and identification of a novel series of inhibitors of integrin VLA-4 are described. Their in vitro activity and selectivity against closely related integrins are also presented.

Comparative in vivo approaches for selective adenovirus-mediated gene delivery to the placenta.

Gene delivery to the placenta is one potential way of specifically modifying placental biological processes and fetal development. The aim of this study was to determine the most efficient and least invasive route of placental adenovirus delivery. The feasibility of adenovirus-mediated gene transfer to the rat placenta was addressed by maternal intravenous or direct intraplacental injection of adenoviral vectors expressing the glucose transporter GLUT3, a noncirculating integral membrane protein. Both routes led to transgene expression in the placenta. However, direct intraplacental delivery on day 14 of gestation yielded a higher transduction efficiency than maternal intravenous administration, and markedly reduced transgene expression in maternal liver. Most importantly, the amount of the GLUT3 transgene and the adenovirus itself in fetal tissues was only 1 to 3% of that found in the placenta. These results indicate that the nature of the transgene and the route of adenovirus administration are key parameters in selective placental somatic gene transfer. This novel strategy may prove useful for modifying a placental function without altering the fetal genome.

[Methodology of DNA fingerprinting and its application in identification of M. tuberculosis].

OBJECTIVE: To explore methodology of DNA fingerprinting technique and its application in identification of strains of M. tuberculosis. METHODS: This research was based on different copy numbers and location of chromosome DNA IS6110 in M. tuberculosis genome. After DNA of M. tuberculosis were cut by endonuclease PvuII, the products were transferred to nylon membrane, then detected and hybridized by enhanced chemiluminescent (ECL) labeling techniques. RESULTS: Fifty clinical isolates from different TB patients had unidentical DNA fingerprinting patterns. DNA fingerprinting patterns showed a great difference from sputum and pus specimens of the same patient. H(37) R(v) ofloxacin resistant and sensitive strains had an identical DNA fingerprinting pattern. CONCLUSIONS: Identification of M. tuberculosis strains is feasible by DNA fingerprinting technique.

Unexpected expression of glucose transporter 4 in villous stromal cells of human placenta.

Glucose transporter 4 (GLUT4) protein expression was characterized in human and rodent term placentas. A 50-kDa protein was detected, by immunoblotting, in term human placenta at levels averaging 25% of those found in white adipose tissue. It was also present, albeit at lower levels, in mouse and rat placentas. The specificity of the 50-kDa signal was established by using skeletal muscle and placental tissues obtained from GLUT4-null mice as controls. Indirect immunohistochemistry, performed in human placentas, showed that intravillous stromal cells were conspicuously labeled by GLUT4 and revealed colocalization of GLUT4 transporters with insulin receptors. This study provides the first evidence that the insulin-responsive GLUT4 glucose transporter is present in human and rodent hemochorial placentas. Placental GLUT4 gene and protein levels were not modified in human pregnancy complicated by insulin-dependent diabetes mellitus. The significance of the high level of GLUT4 protein in human placenta remains to be elucidated, because, so far, this organ was not considered to be insulin-sensitive, with regard to glucose transport.

Production of fertile transgenic peanut (Arachis hypogaea L.) plants using Agrobacterium tumefaciens.

Fertile transgenic plants of peanut (Arachis hypogaea L. cv. New Mexico Valencia A) were produced using an Agrobacterium-mediated transformation system. Leaf section explants were inoculated with A. tumefaciens strain EHA105 harboring the binary vector pBI121 containing the genes for ß-glucuronidase (GUS) and neomycin phosphotransferase II (NPTII). Approximately 10% of the shoots regenerated on selection medium were GUS-positive. Five independent transformation events resulted in the production of 52 fertile transgenic peanut plants. On average, 240 d were required between seed germination for explant preparation and the production of mature t1 seed by T0 plants. Molecular analysis of transgenic plants confirmed the stable integration of the transgenes into the peanut genome. GUS expression segregated in a 3∶1 Mendelian ratio in most T1 generation plants.