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.     

A correlated light and electron microscopic immunocytochemical study of cholinergic terminals and neurons in the rat amygdaloid body with special emphasis on the basolateral amygdaloid nucleus

The cholinergic innervation of the rat basolateral amygdaloid nucleus (BL) was determined by the immunocytochemical localization of the acetylcholine biosynthetic enzyme, choline acetyltransferase (ChAT). ChAT-immunoreactive (ChAT-IR) elements were observed throughout the BL in the form of fine puncta and varicose fibers. Electron microscopy revealed that the immunoreactive puncta represented small terminals (0.3-1.2 micron), most of which formed synaptic contacts with unlabeled dendritic shafts or spines. Less frequently, ChAT-IR terminals established synaptic contacts with large neuronal cell bodies, which had all the characteristics of projection neurons as defined on the basis of axonal projections to the ventral striatum. ChAT-IR terminals were sometimes seen to form synaptic contacts with small neuronal cell bodies, including those of ChAT-IR neurons. The ChAT-IR boutons contained pleomorphic clear vesicles of varying size, and the large majority of the synapses were of the symmetric type. Small ChAT-IR neurons were observed in all parts of the BL. Although the ChAT-IR cell bodies varied widely in shape from typical fusiform to round, most had a more or less oval shape with a major diameter of 10-14 micron. Most of the ChAT-IR neurons seemed to display a radial bipolar dendritic pattern, but multipolar cells were also observed. The ChAT-IR neurons contained an indented nucleus, which was often eccentrically located and surrounded by a thin or moderately thin rim of cytoplasm. The results obtained are discussed in relation to a quasi-cortical organization of the BL.     

Glomerular filtration rate in adults estimated from 123iodine-hippuran and 99mtechnetium-diethylenetriaminepenta-acetic acid gamma camera renography

Summary. In a retrospective study a close relationship was found between the rate constant for renal clearance of the radioactive indicator (λ_pk) and the glomerular filtration rate (GFR) measured by ⁵¹Cr-EDTA plasma clearance. The material comprised eighteen adult subjects submitted to ¹²³I-hippuran gamma camera renography (IHGR) and twenty-two adult subjects to ^99mTc-DTPA gamma camera renography (TDGR). The rate constant was calculated from a bi-exponential decomposition of the activity-time curve recorded within a small region of interest over the left ventricle. The total cleared renal fraction (TCRF) of the cardiac output with respect to the radioactive indicator has previously been shown to be closely related to GFR. A pooled estimate of GFR (GFR_p) was calculated from the stochastically independent estimates of GFR based on λ_pk and TCRF. The comparison of GFR_p with measured GFR was satisfactory and yielded substantially smaller standard deviations (SD) of GFR_p than estimates based on λ_pk and TCRF separately. The standard deviations of GFR_p were about 7 and 12 ml/min/1·73 m² in IHGR for GFR equal to 50 and 100 ml/min/1·73 m², respectively. The corresponding SD in TDGR were about 7 and 11 ml/min/1·73 m². These standard deviations are sufficiently small for many clinical purposes and the method requires no blood samples or urine collections.     

Androgen levels in pregnant women decrease with increasing maternal age

BACKGROUND: To investigate a possible effect of age on maternal androgen levels in uncomplicated pregnancies. METHODS: A study of 134 parous women with uncomplicated pregnancies was carried out at three university hospitals in Norway and Sweden. Maternal levels of androstenedione, dehydroepiandrosterone sulphate, testosterone and the free testosterone index were measured during weeks 17 and 33 of pregnancy. RESULTS: Maternal levels of androstenedione and testosterone had a negative association with maternal age in weeks 17 and 33 of pregnancy, while dehydroepiandrosterone sulphate and the free testosterone index were associated negatively in week 33 only. Adjustment for maternal parity, pre-pregnancy body mass index, smoking and fetal gender did not affect the results. CONCLUSIONS: Maternal androgen levels decrease with increasing maternal age. The cause and possible implication of this finding remain unknown.     

Seroprevalence of human T-lymphotropic virus, hepatitis C virus, and human immunodeficiency virus in Asian American potential bone marrow donors

BACKGROUND: Asian Americans are generally underrepresented both as volunteer blood and bone marrow donors. STUDY DESIGN AND METHODS: To investigate the risk of transfusion transmission of viruses that is associated with increasing participation by Asian American donors, antibodies to human T-lymphotropic virus (HTLV), hepatitis C, and human immunodeficiency virus in Asian American volunteers recruited as potential bone marrow donors were measured. A total of 1354 Asian Americans were enrolled in the study, of whom 54 percent were Chinese, 26 percent Japanese, 9 percent Filipino, 4 percent Korean, 3 percent Indian, and 5 percent of other Asian or mixed Asian and other ethnicity. The majority of the study population was aged 20 through 49 and of high socioeconomic status, as indicated by education and income. Viral antibodies were measured with both screening enzyme-linked immunosorbent assays and supplemental testing, and polymerase chain reaction was used to resolve discrepant HTLV results. RESULTS: Confirmed seroprevalence rates for HTLV were 0.15 percent with one manufacturer's Western blot and 0.3 percent with the other; however, no sample was positive for HTLV types I or II in polymerase chain reaction. Confirmed seroprevalence to hepatitis C virus was 0.5 percent. No subject was seropositive for human immunodeficiency virus. CONCLUSION: On the basis of the moderate size and high education level of this study population, it is concluded that Asian American volunteer bone marrow donors do not pose a greater risk for transmission of HTLV type I or II, human immunodeficiency virus, or hepatitis C virus than does the average American blood donor.     

Long-term use of antecubital veins for plasma exchange. The Canadian Cooperative Multiple Sclerosis Study Group

True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access.     

Ostomy bag management: comparative study of a new one-piece closed bag

The aim of this study was to compare the performance of a new one-piece closed ostomy bag, SenSura, to an already established bag with a focus on minimizing problems related to use of stoma bags for individuals with a colostomy. There were 68 Danish participants with a colostomy who tested each bag for 1 week in a randomized, open, comparative, crossover study. The SenSura bag was perceived more secure than the reference bag (p=0.0006). Crucial performance and safety parameters were rated significantly better for SenSura than for the reference bag. The high preference for SenSura (85%) reflected these results (p<0.0001). Individuals with a colostomy can expect a higher sense of security with the SenSura bag than with the reference bag. This may relate to good adhesion, tack, flexibility and effective filter performance. Future studies should examine the long-term effects of SenSura on peristomal skin conditions. To our knowledge, this is the first published comparative study of one-piece closed ostomy bags.     

Multicenter evaluation of a fully mechanized soluble transferrin receptor assay on the Hitachi and cobas integra analyzers. the determination of reference ranges.

Soluble transferrin receptor (sTfR) is reported to be a reliable marker for the diagnosis of iron deficiency, especially when iron metabolism is influenced by inflammatory disorders such as infection, chronic inflammation and cancer-related anemia. In the present multicenter study the analytical performance of a recently introduced, latex-enhanced immunoturbidimetric assay for the determination of soluble transferrin receptor (Tina quant [a] sTfR, Roche Diagnostics) on different fully mechanized analyzers such as Hitachi 917 and 911, and Cobas Integra 400 and 700 was evaluated. Within-run and between-run imprecision showed good results (CV<5% and <7%, respectively). The assay was found to be linear over a wide measuring range (0.4-35 mg/l). Endogenous substances did not interfere with the test results. Comparison of serum sTfR concentrations with those of heparinized plasma revealed good correlation (r>0.976). Method comparison with an existing fully mechanized method as well as with ELISA tests for sTfR showed very good correlation (r>0.987). Because of the lack of international standardization the results differed from each other up to 2.5-fold. The 95% of serum levels in healthy individuals ranged from 1.9 to 4.4 mg/l (n=427). However, the reference ranges should be reported in a sex-dependent manner, as 2.2-5.0 mg/l for men (n=211) and as 1.9-4.4 mg/l for premenopausal (n=216) and postmenopausal (n=45) women. The Tina quant [a] sTfR assay enables the precise, accurate, rapid and convenient determination of sTfR concentrations for routine clinical chemistry purposes.     

La nécrosectomie transgastrique

La nécrosectomie transgastrique semble être une alternative présentant peu de risques de traitement pour les patients gravement atteints. Cependant, il manque à ce jour, une analyse des risques du procédé sur un nombre suffisant de patients; il est urgent de procéder à des collectes de données multicentriques. Il s’agit de procédés endoscopiques complexes, qui nécessitent une grande expérience, et le traitement de chaque patient devrait être planifié de fa?on interdisciplinaire en collaboration avec le chirurgien. Ce procédé devrait par conséquent rester limité aux centres spécialisés.