Flexible tantalum stents implanted in aortas and iliac arteries: effects in normal canines

Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study.     

Chondromalacia patellae: assessment with MR imaging

Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.     

丹参酮ⅡA对神经祖细胞系C17．2的保护作用

目的:了解丹参酮ⅡA对神经祖细胞系C17.2的保护作用,探讨其可能的作用机制。方法:本实验于2005年起在广州血液中心器官移植配型中心实验室进行。C17.2祖细胞系由澳大利亚新南威尔士大学解剖教研室David Walsh博士惠赠。将C17.2细胞以1×109L-1的密度接种,用含10%胎牛血清IMDM,37℃、体积分数为0.05CO2、饱和湿度的CO2培养箱培养,接近融合的C17.2细胞用含0.1mmol/LEDTA的胰酶室温消化,按1∶3的比例传代。C17.2细胞以5×107L-1的密度接种于96孔板或25cm2的培养瓶中,用含10%胎牛血清IMDM培养过夜后,加入含4g/L AAPH(水溶性偶氮引发剂2,2'-偶氮二(2-脒基丙烷)二盐酸盐)无血清的IMDM培养基培养建立神经细胞凋亡模型。C17.2细胞以5×103/孔的密度接种于96孔板中,用含10%胎牛血清IMDM培养过夜后,加入含4g/LAAPH无血清的IMDM培养基培养。对照组不加入丹参酮ⅡA,实验组分别加入0.02,0.05,0.1,0.2mg/L丹参酮ⅡA培养8h,噻唑蓝法检测细胞活性:细胞活性的相对值=(实验组吸光度值/对照组吸光度值)×100%,流式细胞仪检测细胞凋亡。结果:①AAPH处理8h后,C17.2细胞被过氧化损害,大多数细胞失去正常的形态,细胞呈圆形,脱落。加入丹参酮ⅡA后,细胞形态基本保持正常,少数细胞呈圆形。②C17.2细胞在IMDM的培养液中,细胞数量是含4g/L AAPH无血清的IMDM培养基条件下的2.5～3倍。浓度为0.02,0.05,0.1mg/L的丹参酮ⅡA对C17.2细胞有保护作用,质量浓度大于0.2mg/L丹参酮ⅡA对C17.2细胞保护作用降低。③AAPH作用前大部分C17.2细胞的线粒体完整,有少量的早期凋亡细胞和凋亡细胞,AAPH作用后凋亡细胞总数、凋亡细胞明显增加。丹参酮ⅡA处理组可以明显减少早期凋亡细胞。结论:在体外丹参酮ⅡA对神经细胞具有抗凋亡的作用,可以保护神经细胞。     

Consensus of microbiology reporting of ear swab results to primary care clinicians in patients with otitis externa

Otitis externa is a ubiquitous inflammatory disease; although it arises most commonly from an infection, there is no consensus in the UK for the reporting of ear swab culture results. This study aims to review current microbiology laboratory reporting of ear swab specimens to primary care and reach an evidence-based consensus for a reporting policy. Fifty consecutive ear swab reports were reviewed from each of 12 laboratories in the South West region to determine and discuss reporting practice. The Health Protection Agency (HPA) GP Microbiology Laboratory Use Group reviewed the underlying evidence and worked towards a consensus of expert microbiology opinion for laboratory reporting of ear swab results using a modified version of the Delphi technique. A total of 487 reports from primary care were reviewed (54% female; 46% male). Cultures most commonly yielded Pseudomonas species (36%), Staphylococcus species (21%), Streptococcus species (15%) and fungi (11%). Five reporting policies were agreed: Policy 1: Common pathogens such as group A beta-haemolytic streptococci, Streptococcus pneumoniae, Staphylococcus aureus - Always reported by name with antibiotic susceptibilities. Policy 2: Pseudomonas species - Always reported, but antibiotic susceptibilities only reported in severe disease. Policy 3: Aspergillus, Candida, coliforms and Proteus species, as well as non-group A streptococci and anaerobes - Only reported if moderate numbers of colonies and it is the predominant organism present; if appropriate report antibiotic susceptibilities. Policy 4: Coagulase-negative staphylococci, diphtheroids and enterococci - Not reported by name; generic terms used and antibiotic susceptibilities not reported. Policy 5: When antibiotic susceptibilities reported these must include susceptibility to a topical antibiotic. It is suggested that laboratories should consider adopting this evidence-based reporting consensus for ear swab culture results from primary care patients with otitis externa.     

Quantification of MPTP-induced dopaminergic neurodegeneration in the mouse substantia nigra by laser capture microdissection

The neurotoxin MPTP is widely used to cause damage to the dopaminergic system in rodents and non-human primates to model various aspects of Parkinson's disease. In mice, depletion of striatal dopamine is the commonly used endpoint to assess neuronal damage. However, it has proved technically challenging to quantify dopaminergic cell bodies as an index of neuronal integrity. To meet this challenge, we applied laser pressure catapult microdissection (LCM) of the substantia nigra in combination with quantitative Western blot to provide an index of dopamine neurodegeneration in mice treated with MPTP. Seven days following initiation of MPTP treatment, striatal dopamine depletion was maximal and there was histological evidence of neuronal degeneration in the substantia nigra. To index the integrity of dopamine cell bodies, tyrosine hydroxylase (TH) and beta-actin were quantified by Western blot in LCM extracts. In untreated mice, TH was detected in LCM extracts of substantia nigra but was undetectable in equivalently sized extracts of cortex from the same animals. In MPTP-treated mice, there was a significant 70% reduction in TH relative to beta-actin in LCM extracts as compared to vehicle-injected controls. This reduction corresponded to decreases in striatal dopamine and loss of immunocytochemically detected TH but not beta-actin in the substantia nigra (SN). Thus, this method provides a quantitative means to measure dopamine neuron toxicity in the substantia nigra and, as such has potential application in evaluating regimens that may be neuroprotective or neurorestorative for dopaminergic neurons.     

Modulation of ischaemic contracture in mouse hearts: a 'supraphysiological' response to adenosine

While inhibition of ischaemic contracture was one of the first documented cardioprotective actions of exogenously applied adenosine, it is not known whether this is a normal function of endogenous adenosine generated during ischaemic stress. Additionally, the relevance of delayed contracture to postischaemic outcome is unclear. We tested the ability of endogenous versus exogenous adenosine to modify contracture (and postischaemic outcomes) in C57/Bl6 mouse hearts. During ischaemia, untreated hearts developed peak contracture (PC) of 85 +/- 5 mmHg at 8.9 +/- 0.8 min, with time to reach 20 mmHg (time to onset of contracture; TOC) of 4.4 +/- 0.3 min. Adenosine (50 microm) delayed TOC to 6.7 +/- 0.6 min, as did pretreatment with 10 microm 2-chloroadenosine (7.2 +/- 0.5 min) or 50 nm of A(1) adenosine receptor (AR) agonist N(6)-cyclohexyladenosine (CHA) (6.7 +/- 0.3 min), but not A(2A)AR or A(3)AR agonists (20 nm 2-[4-(2-carboxyethyl) phenethylamino]-5' N-methylcarboxamidoadenosine (CGS21680) or 150 nm 2-chloro-N(6)-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (Cl-IB-MECA), respectively). Adenosinergic contracture inhibition was eliminated by A(1)AR gene knockout (KO), mimicked by A(1)AR overexpression, and was associated with preservation of myocardial [ATP]. This adenosine-mediated inhibition of contracture was, however, only evident after prolonged (10 or 15 min) and not brief (3 min) pretreatment. Ischaemic contracture was also insensitive to endogenously generated adenosine, since A(1)AR KO, and non-selective and A(1)AR-selective antagonists (50 microm 8-sulphophenyltheophylline and 150 nm 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX), respectively), all failed to alter intrinsic contracture development. Finally, delayed contracture with A(1)AR agonism/overexpression or ischaemic 2,3-butanedione monoxime (BDM; 5 microm to target Ca(2+) cross-bridge formation) was linked to enhanced postischaemic outcomes. In summary, adenosinergic inhibition of contracture is solely A(1)AR mediated; the response is 'supraphysiological', evident only with significant periods of pre-ischaemic AR agonism (or increased A(1)AR density); and ischaemic contracture appears insensitive to locally generated adenosine, potentially owing to the rapidity of contracture development versus the finite time necessary for expression of AR-mediated cardioprotection.     

Clinical multimorbidity and physical function in older adults: a record and health status linkage study in general practice

BACKGROUND: Multiple chronic conditions occurring in the same individual are associated with adverse health outcomes. In family practice, individuals are seen who, over time, may experience many different symptoms, illnesses and chronic diseases. Measures for defining multimorbidity, which incorporate the diverse range of health problems seen in population-based family practice, remain to be developed. We have investigated whether routinely collected consultation data could be used as the basis for a simple classification of multimorbidity that reflects an individual's overall health status. METHODS: Morbidity consultation data for 9,439 English patients aged 50 years and over in an 18-month time period were linked to their self-reported physical health status measured by Short-Form 12 at the end point. Associations between physical function and all-cause multimorbidity counts were estimated relative to single morbidity only, and between physical function and morbidity severity (185 morbidities categorized on four ordinal scales of severity) relative to persons who had not consulted about any of the 185. RESULTS: In the 18-month period, 19% had consulted for a single morbidity and 23% for six or more (a high multimorbidity count). An estimated 24% of poor physical function in the family practice consulting population may be attributable to high multimorbidity. There was an increasing strength of association between poor physical function and increasing severity of multimorbidity on all four severity scales. Estimated associations (adjusted odds ratios) of the most severe morbidity categories with poor physical function were, for each of the four scales, respectively, 5.6 for chronicity [95% confidence interval (CI) 4.4-7.1], 7.0 for time course (4.5-10.6) and 3.6 for health care use (2.0-6.6) and for patient impact (6.7; 5.2-8.8). CONCLUSIONS: Multimorbidity defined by using routinely collected family practice consultation data and classified by count and by severity was associated with poorer physical function. This approach offers the potential for systematic use of routine records to classify multimorbidity and to identify groups with high likelihood of poor physical status for needs assessment and targeted intervention.     

Virtual colonoscopy with magnetic resonance imaging: In vitro evaluation of a new concept

BACKGROUND & AIMS: Screening for colonic polyps is desirable. A new concept based on cross-sectional and endoscopic analysis of a magnetic resonance (MR) data set is presented. METHODS: Ex vivo autopsy colonic specimens, containing artificially placed polyps, were obtained and filled with a gadolinium-containing solution. Forty-four thin-section MR images were obtained in a 1.5-T MR scanner in 28 seconds. A three- dimensional endoscopic fly-through of these images was rendered. Fly- throughs and two-dimensional cross-sectional images were analyzed by two observers for the presence of polyps. RESULTS: The average sensitivity and specificity for the detection of polyps based on three- dimensional endoscopic MR colon imaging were 87% and 96%, respectively. Analysis of cross-sectional images showed an overall sensitivity and specificity of merely 57% and 84%, respectively. The difference in the interpretation of three-dimensional MR colonoscopy and two-dimensional cross-sections was statistically significant (P < 0.001). With three- dimensional MR colonoscopy, overall sensitivity for detection of polyps measuring < or =5 mm in length and diameter was 70%; for larger polyps, it increased to 95% (P < 0.01). CONCLUSIONS: The feasibility of an MR- based endoluminal assessment of the colon is shown. Minimal invasiveness, lack of radiation exposure, and high in vitro diagnostic accuracy warrant further investigation of this novel concept. (Gastroenterology 1997 Jun;112(6):1863-70)