Radionuclide-anesthetic flow study: a new technique for the study of regional anesthesia

A new technique to study the dynamics of in vivo distribution of regional anesthetics is described. Five hundred microcuries of technetium-99m diethylenetriaminepentaacetic acid (DTPA) added to the anesthetic in a syringe prior to injection allows both dynamic and static imaging to assess the initial distribution of the injected anesthetic. Superimposed bone scans or transmission scans help delineate anatomy. The radionuclide-anesthetic flow study is a simple, safe technique to investigate both the spread of regional anesthetics and the factors that affect it.     

Femoral capital osteonecrosis: MR finding of diffuse marrow abnormalities without focal lesions

Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head.     

Iron, ascorbate and copper status of Sowetan Blacks with calcific chronic pancreatitis

Vitamin C can be used to overcome oxidative stress and ease pain in chronic pancreatitis. But its use is deprecated in conditions of tissue iron overload, because its bioactive form, ascorbate, can accelerate free-radical reactions that are driven by transition metals. We measured iron, ascorbate and copper in Sowetan Blacks (RSA) with chronic pancreatitis, obtaining serum/plasma from 14 consecutive patients and 15 controls. Compared with data from corresponding groups in Manchester, African samples had less ascorbate (p < 0.0001), but more caeruloplasmin (p < 0.0001). African and British controls had comparable iron and iron-binding capacity. Plasma from African patients had less ascorbate than that from African controls (p < 0.005) and in six samples, ferritin exceeded 300 micrograms/l (677 pmol/l). Low- molecular-mass iron or copper, capable of participating in free radical reactions, was not detected. British patients, had similar caeruloplasmin levels to African patients but higher ascorbate levels. There is no evidence of iron overload in our African samples. Outwardly healthy controls from Soweto have elevated levels of caeruloplasmin, possibly to compensate for dietary deficiency of ascorbate. Persistent oxidative stress is a unifying feature of chronic pancreatitis, but its degree is higher in African than British patients. Supplements of vitamin C should be safe in Blacks of southern Africa.      

Vertebral Fracture Risk in Diabetic Elderly Men: The MrOS Study

Type 2 diabetes (T2DM) is associated with a significant increase in risk of nonvertebral fractures, but information on risk of vertebral fractures (VFs) in subjects with T2DM, particularly among men, is lacking. Furthermore, it is not known whether spine bone mineral density (BMD) can predict the risk of VF in T2DM. We sought to examine the effect of diabetes status on prevalent and incident vertebral fracture, and to estimate the effect of lumbar spine BMD (areal and volumetric) as a risk factor for prevalent and incident morphometric vertebral fracture in T2DM (n = 875) and nondiabetic men (n = 4679). We used data from the Osteoporotic Fractures in Men (MrOS) Study, which enrolled men aged ≥65 years. Lumbar spine areal BMD (aBMD) was measured with dual‐energy X‐ray absorptiometry (DXA), and volumetric BMD (vBMD) by quantitative computed tomography (QCT). Prevalence (7.0% versus 7.7%) and incidence (4.4% versus 4.5%) of VFs were not higher in T2DM versus nondiabetic men. The risk of prevalent (OR, 1.05; 95% CI, 0.78 to 1.40) or incident vertebral‐fracture (OR, 1.28; 95% CI, 0.81 to 2.00) was not higher in T2DM versus nondiabetic men in models adjusted for age, clinic site, race, BMI, and aBMD. Higher spine aBMD was associated with lower risk of prevalent VF in T2DM (OR, 0.55; 95% CI, 0.48 to 0.63) and nondiabetic men (OR, 0.66; 95% CI, 0.5 to 0.88) (p for interaction = 0.24) and of incident VF in T2DM (OR, 0.50; 95% CI, 0.41 to 0.60) and nondiabetic men (OR, 0.54; 95% CI, 0.33 to 0.88) (p for interaction = 0.77). Results were similar for vBMD. In conclusion, T2DM was not associated with higher prevalent or incident VF in older men, even after adjustment for BMI and BMD. Higher spine aBMD and vBMD are associated with lower prevalence and incidence of VF in T2DM as well as nondiabetic men. © 2017 American Society for Bone and Mineral Research.     

自体造血干细胞的体外净化

目的:综合分析自体造血干细胞体外净化的方法。资料来源:应用计算机检索Medline 1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“purging,HSCT”,并限定文章语言种类为English。同时计算机检索CNKI数据库1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“体外净化,PUVA”,并限定文章语言种类为中文。资料选择:对相关资料进行整理,选取同一领域、不同方面的文献,以近期发表或权威杂志的文章优先。资料提炼:共检索到42篇有关自体造血干细胞体外净化方法的文献,其中24篇文章符合要求。排除18篇,其中15篇系重复同一研究,3篇为Meta分析。资料综合:自体造血干细胞的体外净化方法很多,如物理方法、生物学方法、药物方法、免疫净化、基因净化等。每种净化方法都有其各自的优势和不足,如淋巴系统疾病可以采用免疫净化;慢性粒细胞白血病患者可考虑反义技术;大多数患者则均可以考虑药物净化的方法。结论:针对不同的疾病,可以选择不同的净化方法,还可以将几种净化方法联合起来,其效果和方法的改进也在不断的研究探索中。     

Reduction in transmission of hepatitis C after the introduction of a heat-treatment step in the production of C1-inhibitor concentrate

BACKGROUND: The transmission of viral infections via protein concentrates made from a large pool of plasma depends on the selection of donors, fractionation process, and virucidal methods. To date, no data are available on the infectivity risk of plasma concentrates of the inhibitor of the first component of complement (C1-INH). STUDY DESIGN AND METHODS: The prevalence of blood-borne viral infections and levels of transaminases were evaluated in patients treated with a large- pool plasma concentrate of the inhibitor of C1-INH before and after the introduction of virucidal methods. The study included 85 patients with hereditary angioedema and 4 with acquired angioedema. The patients were divided into three groups: 1) 48 untreated patients; 2) 22 patients treated with non-virus-inactivated C1-INH concentrates; and 3) 19 patients treated with virus-inactivated concentrates. Serum samples obtained at various times after the infusion of concentrate were assayed for alanine amino-transferase and tested for hepatitis B surface antigen and antibodies to hepatitis C virus (anti-HCV) and human immunodeficiency virus (anti-HIV); anti-HCV-negative subjects exposed to the concentrate were also tested for HCV RNA. RESULTS: Prevalences of HCV infection and elevated alanine aminotransferase are significantly lower in patients treated with virus-inactivated concentrates than in those exposed to non-virus-inactivated concentrates. No patients were anti-HIV positive. CONCLUSION: This study suggests that C1-INH concentrates transmitted HCV, but that the virucidal methods adopted are effective in reducing the infectivity.     

Polyethylene glycol versus low-ionic-strength solution in pretransfusion testing: a blinded comparison study

BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies.