The intron 4c allele of the NOS3 gene is associated with ischemic stroke in African Americans

Background  

Ischemic stroke is the most common cause of disability in North America and in addition to the generally accepted risk factors, there is increasing evidence for the potential pathophysiological role of genes. One of these genes, the endothelial nitric oxide synthase gene (NOS3) has been reported as a genetic risk factor for ischemic stroke. To independently confirm and extend the results of these previous reports, we investigated this gene as a risk factor for stroke in an ethnically diverse study population.     

Identification of different states of hepatitis B virus infection with a quantitative PCR assay

The level of hepatitis B virus (HBV) DNA in serum reflects the replicative activity of HBV. To compare serum HBV DNA levels in different states of hepatitis B, 47 sera of patients with HBeAg-positive chronic hepatitis B, 4 sera of patients with HBeAg-negative chronic hepatitis B, 40 samples of patients after HBeAg seroconversion during alpha interferon treatment, 57 sera of inactive HBsAg carriers, and 42 sera of patients who had recovered from chronic hepatitis B more than 12 months prior to blood collection were checked for the presence of HBV DNA with the Amplicor HBV Monitor Test. In patients with HBeAg-positive chronic hepatitis B, the median of serum HBV DNA levels (8.3 x 10(8) copies/ml) was significantly higher than that for patients after HBeAg seroconversion (6.2 x 10(3) copies/ml) and than that for inactive HBsAg carriers (5.6 x 10(3) copies/ml). None of the patients who had recovered from hepatitis B had detectable HBV DNA in serum. Quantitative PCR proved to be a valuable tool for identification of different states of HBV infection. This technique was found to be a good method for determination of serum HBV DNA levels both for patients with HBeAg seroconversion and for inactive carriers who showed low viremia not detectable by conventional hybridization assays.     

Differential effects of simian immunodeficiency virus infection on immune inductive and effector sites in the rectal mucosa of rhesus macaques

The rectal mucosa, a region involved in human immunodeficiency virus/simian immunodeficiency virus (SIV) infection and transmission, contains immune inductive sites, rectal lymphoid nodules (RLN), and effector sites, the lamina propria (LP). This study was designed to evaluate cell populations involved in rectal mucosal immune function in both RLN and LP, by immunocytochemical analysis of rectal mucosa from 11 SIV-infected (2 to 21 months postinfection) and five naive rhesus macaques. In the rectum, as previously observed in other intestinal regions, CD4(+) cells were dramatically reduced in the LP of SIV-infected macaques, but high numbers of CD4(+) cells remained in RLN indicating maintenance of T cell help in inductive sites. Cells expressing the mucosal homing receptor alpha4beta7 were dramatically decreased in the RLN and LP of most SIV-infected macaques. The RLN of both naive and SIV-infected macaques contained high numbers of CD68 + MHC-II+ macrophages and cells expressing the co-stimulatory molecules B7-2 and CD40, as well as IgM + MHCII+ and IgM + CD40+ B cells, indicating maintenance of antigen presentation capacity. The LP of all three macaques SIV-infected for 2 months contained many B7-2+ cells, suggesting increased activation of antigen-presenting cells. LP of SIV-infected rectal mucosa contained increased numbers of IgM+ cells, confirming previous observations in small intestine and colon. The data suggest that antigen-presentation capacity is maintained in inductive sites of SIV-infected rectal mucosa, but immune effector functions may be altered.     

Angular displacement perception modulated by force background

We had recumbent subjects (n = 7) indicate the amplitude of imposed, passive yaw–axis body rotations in the 0, 1, and 1.8 g background force levels generated during parabolic flight maneuvers. The blindfolded subject, restrained in a cradle, aligned a gravity-neutral pointer with the subjective vertical while in an initial position and then tried to keep it aligned with the same external direction during a body rotation, lasting less than 1.5 s about the z-axis 30°, 60°, or 120° in amplitude. All the rotations were above semicircular threshold levels for eliciting perception of angular displacement under terrestrial test conditions. In 1 and 1.8 g test conditions, subjects were able to indicate both the subjective vertical and the amplitude of the body rotation reasonably accurately. By contrast in 0 g, when indicating the subjective vertical, they aligned the pointer with the body midline and kept it nearly aligned with their midline during the subsequent body tilts. They also reported feeling supine throughout the 0 g test periods. The attenuation of apparent self-displacement in 0 g is discussed in terms of (1) a possible failure of integration of semicircular canal velocity signals, (2) a contribution of somatosensory pressure and contact cues, and (3) gravicentric versus body-centric reference frames. The significance of the findings for predicting and preventing motion sickness and disorientation in orbital space flight and in rotating artificial gravity environments is discussed.     

Health care financing policy for hospitalized pediatric patients

Prospective hospital payment systems using the federal Medicare DRG payment model are changing hospital reimbursement. Currently, many states have adopted diagnosis related group (DRG) prospective "all payer systems" using the federal model. All payer systems, whereby Medicaid, Blue Cross, and other commercial insurers pay by the DRG mode, prevent cost shifting between payers. New York state has used an all payer system since Jan 1, 1988. This study simulated DRG all payer methods for a large sample (N = 16,084) of pediatric patients for a three-year period using the New York DRG all payer reimbursement system now in effect. Medicaid pediatric patients had (adjusted for DRG weight index) a longer hospital stay and greater total hospital cost compared with pediatric patients from Blue Cross and other commercial payers. Medicaid pediatric patients also had a greater severity of illness compared with patients from Blue Cross and other payers. Pediatric patients in all payment groups (ie, Medicaid, Blue Cross, and other commercial insurers) generated financial risk under the DRG all payer scheme. Medicaid pediatric patients generated the greatest financial risk, however. These data suggest that state and private payers may be under-reimbursing for the care of the hospitalized pediatric patient using the DRG prospective hospital payment scheme. Health care financing policy for pediatric patients may limit both access and quality of care.     

Nitinol micro-forceps for retrieval of intravascular objects: first in vitro experiences

RATIONALE AND OBJECTIVE: With the progress of interventional procedures the need for retrieval of iatrogenic materials increases. Here we introduce a new nitinol micro-forceps for retrieval of intravascular objects and report our first in-vitro experiences. MATERIALS AND METHODS: In a tube model simulating arterial anatomy a total of eight endovascular coils were removed from the "carotid artery" using a "trans-femoral" approach. Additionally, the withdrawal of grasped coils through vascular sheaths of F-5, F-6, F-8, F-12 was observed (n = 4/seize). RESULTS: Seven of 8 coils were successfully grasped. Loss of one coil occurred during retrieval. Withdrawal of coils through a vascular sheath was possible only when the coil was grasped at one of its ends. DISCUSSION: The nitinol micro-forceps proved to be a potential tool in endovascular retrieval of foreign objects especially in small caliber vessels. However, further technical modifications are necessary to improve maneuverability and grasping strength.     

Endovascular gamma irradiation of femoropopliteal de novo stenoses immediately after PTA: interim results of prospective randomized controlled trial

PURPOSE: To report an interim analysis of whether centered endovascular irradiation with the iridium 192 ((192)Ir) source immediately after percutaneous transluminal angioplasty (PTA) of de novo femoropopliteal stenoses lowers the restenosis rate. MATERIALS AND METHODS: Thirty patients undergoing PTA to treat femoropopliteal stenoses were randomized for prophylaxis against restenosis with centered endovascular irradiation with a (192)Ir source (a dose of 14 Gy 2 mm deep to the vessel wall, irradiation group) or no irradiation (control group). Angiographic follow-up was available for 22 patients at 6 months (irradiation group, n = 10) and 12 patients at 12 months (irradiation group, n = 6). Duplex sonography, treadmill testing, and interviews were performed the day before and the day after PTA and after 1, 3, 6, 9, and 12 months. Results of angiography, duplex sonography, treadmill testing, and interviews were evaluated with a t test and multivariate analysis of variance (clinical characteristics, chi(2) test). RESULTS: Baseline characteristics were comparable in the two groups. Interim analysis of the 6-month follow-up data revealed a trend toward a significantly lower restenosis rate in the irradiation group. The change in the degree of stenosis compared with that after PTA was -14.7% +/- 20.8 (mean +/- SD) in the irradiation group versus 37.7% +/- 27.3 in the control group (P =.001) and became even more marked at 12 months (-9.5% +/- 34.5 vs 45.5% +/- 40.7 [P =.03], respectively). The follow-up results of treadmill testing and interviews showed a nonsignificant benefit for the irradiation group. One thromboembolic complication occurred during irradiation. No side effects were observed during follow-up. CONCLUSION: Endovascular irradiation with a centered (192)Ir source immediately after PTA of de novo femoropopliteal stenoses reduces the restenosis rate.