Detection of Atrial Fibrillation by Implanted Devices with Wireless Data Transmission Capability

Remote telemetry may facilitate the management of implantable devices. We tested the reliability of a new automatic, wireless home monitoring (HM) system that archives data every 24 hours. We retrospectively analyzed archival data from 276 consecutive pacing system implants to define temporal atrial fibrillation (AF) patterns and associated ventricular rate. An "AF day" was defined by a >20%/24 hour mode switch (MS) duration, irrespective of the MS number. Management decisions resulting from transmissions were noted. A pilot study confirmed that 89% of 22,356 transmissions were successful, of which >90% were received in <5 minutes. Data integrity was 100% preserved. Overall, AF developed in 29 patients (10.5%), representing a total of 645 AF days (mean = 22.2 ± 29.6 AF, median = 9 days), over 12 ± 2 months of monitoring. AF was infrequent (50% of 24 hours. Ventricular rates during 645 AF days in 29 patients averaged 95.1 ± 9.9 beats/min (median = 94 beats/min). Ventricular rates were >80 beats/min in 25 ± 30 AF days (median = 11 days). HM enabled rapid anticoagulation decisions. In recipients of implantable devices, automatic wireless telemetry with HM was efficient and reliable. Its application may overcome some current challenges in AF management by early notification and precise measurement of both AF burden and ventricular rate during AF.     

Proliferation of DU145 prostate cancer cells is inhibited by suppressing insulin-like growth factor binding protein-2

BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer.     

Immunogenicity study of low-dose administration of hepatitis B virus vaccine in newborn infants: A cost reduction trial

Different doses of hepatitis B virus vaccine—prepared by Korea Green Cross Corporation, were given to healthy infants born to HBsAg-negative mothers at birth, 1 and 6 months of age. A dose of 2 μg was administered intradermally in Group A and, in the three other groups, the vaccine was given intramuscularly (i.m.). An adequate follow-up observation was possible for 9 months after birth in 22, 25, 23 and 21 infants in Groups A, B, C and D, respecvely.
Group C (5 μg, i.m.) produced seroconversion most rapidly, showing the highest rate (96%) at 9 months of age. The lowest seroconversion rate (5%) was found at the age of 1 month in Group A subjects, but the rate increased to 91% after a booster dose was given at 6 months of age.
While it can be concluded that a 5 μg i.m. dose of vaccine at 0, 1 and 6 months of age is optimum for the immunization of infants in efficacy and economy, a 2 μg intradermal dose can also be considered as an immunogenic and economical regimen, though the immune response is slower and a special technique is required for immunization.     

Healthy communities: reflections on building alliances in Canada. A view from the middle

The author is currently working in the office of Health Promotion,Ministry of Health in British Columbia. For the past 17 yearsshe has worked in Health and Welfare Canada as an advocate forcitizen participation in developing health programs and policies. This article is based on her experience as an advocate and bureaucratin translating and mediating health promotion rhetoric intoaction. The Canadian Healthy Communities and Strengthening Communitiesprojects are used as examples in analyzing the opportunitiesand contradictions in building alliances.     

Chemical and enzymatic treatment of endothelin

Endothelin-1 (ET), the most potent vasoconstrictor yet discovered, is a peptide containirig 21 amino acids with two intrachain disulfide bridges. With the aim of obtaining two-chain derivatives, Et was submitted to chemical and enzymatic treatments. Reaction of ET with CNBr in 70% HCOOH gave, in addition to the expected [Hse⁷ lactone]-7,8-seco-ET and unreacted material, a by-product whose molecular weight was 25 m.u. greater than that of ET. When the reaction mixture, after lyophilisation, was immediately quenched with NH3-saturated dry MeOH, two products could be recovered in a 5:1 ratio, both obtained by nucleophilic attack of the homoserine lactone: the expected [Hse⁷-NH₂]-7,8-seco-ET and [Hse⁷]ET, resulting from competitive intramolecular reaction of the deprotonated α-amino group of the Asp⁸ residue. The Lys⁹-Glu¹⁰ bond turned out to be very resistant to enzymatic attack both by Lys-C-endopeptidase and trypsin. The 9,10-seco-ET derivative could be obtained by treatment with Lys-C-endopeptidase only by using a high enzyme/ET ratio and after a prolonged incubation time. Cleavage of the Lys⁹-Glu¹⁰ bond could not be achieved by treatment with trypsin, even with a high enzyme/substrate ratio. The main product was 13, 14-seco-ET, deriving from the action of chymotripsin (present as an impurity in the trypsin preparation) on Tyr¹³. The structure of these peptides was confirmed by amino-acid sequence analysis and fast atom bombardment mass spectrometry (FAB-MS). Nicking of the ET structure at different positions had different impact on the biological properties of the resulting derivatives. © Munksgaard 1995.     

Computer-Assisted Design of an Implantable, Intrathoracic Artificial Lung

Abstract: A semiempirical mathematical model of convective oxygen transport is used to design a new, low pressure loss, implantable artificial lung that could be used as a bridge to lung transplantation in patients with advanced respiratory failure. The mass transfer and flow friction relations pertinent to the design of a cross–flow hollow fiber membrane lung are described. The artificial lung is designed to transfer over 200 ml/min of oxygen at blood flow rates up to 5 L/min. A compact design and a blood-side pressure loss of <15 mm Hg allows the device to be implanted in the left chest without the need for a prosthetic blood pump. Surgical implantation of the artificial lung would require the creation of inflow and outflow anastomoses. Oxygen would be supplied via an external source. Blood properties, operating conditions, and empirically determined mass transfer and flow properties are all specified and input into a computer program that numerically solves the design equations. Computer–generated values for the device frontal area, blood path length, and fiber surface area are thereby obtained. The use of this computer–assisted design minimizes the need for extensive trial–and–error testing of prototype devices. Results from in vitro tests of a prototype implantable lung indicate that the mathematical model we describe is an accurate and useful tool in the design of hollow fiber artificial lungs.     

Activation of mRNA expression of collagen,collagenase and its inhibitor on renal biopsy specimens in patients with IgA nephropathy

Summary: In situ hybridization of mRNA for collagen IV, collagen VI, stromelysin (MMP-3) and TIMP1 was examined in renal biopsy specimens from patients with IgA nephropathy (IgAN) or diabetic nephropathy with various degrees of tissue damage. The majority of cells in the glomeruli expressed these mRNA almost simultaneously, but a few cells demonstrated positive expression for only one of these probes. There was a parallel relationship between the degree of tissue damage and that of mRNA expressions of these probes in patients with IgAN, while patients with diabetic nephropathy showed a reverse relationship between these two parameters. It is concluded that patients with mesangial proliferative glomerulonephritis expressed mRNA for collagen collagenase and its inhibitor in the glomeruli in parallel with the progress of tissue damage. In contrast, glomerular samples from patients with diabetic nephropathy showed that there was an inverse relationship between tissue damage and expression of mRNA. It is concluded that expression of collagen, collagenase and its inhibitor parallels the progression of glomerular changes in IgAN, but such parallel expression was not observed in patients with diabetic nephropathy.     

经桡动脉冠状动脉介入治疗中5F与6F导引导管的对比研究

目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33～81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。     

Comparison of gene therapy strategies for treatment of liver diseases

Abstract   Liver-directed gene therapy can be aimed at replacing a missing gene product, overexpressing or ectopically expressing a gene product in the liver, generating proteins that are normally not produced in the liver (e.g. hormones, vaccines), down-regulating specific gene expression and targeted repair of genetic mutations. A common critical requirement for achieving these goals is the availability of efficient methods for transferring DNA and RNA into target organ in vivo . Both recombinant viruses and non-viral vectors are being explored for transferring nucleic acids to cells in vitro and in vivo . This review compares the characteristics of these vectors in the context of their potential application in liver-directed gene therapy for various inherited or acquired disorders.