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Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor.  相似文献   
3.
Three isoforms of human tau protein were compared for their abilities to induce microtubule assembly. The three isoforms, tau 3 (tau containing three microtubule-binding domains), tau 4 (tau containing four microtubule-binding domains) and tau 4L (tau containing four microtubule binding domains plus a 58-amino-acid insert near the N-terminus) were expressed in E. coli and purified using ammonium sulfate precipitation, ion exchange, and size exclusion chromatography. All three isoforms induced microtubule assembly at micromolar concentrations and showed similar critical concentrations for assembly of 0.4-0.45 microM. However, tau 4 induced microtubule formation at a rate five- to tenfold faster than either tau 3 or tau 4L. The rate of microtubule elongation seen with tau 4 was twofold greater than with tau 3 or tau 4L, suggesting that the faster rate of microtubule assembly seen with tau 4 was due, at least in part, to faster elongation. Tau 4 induced a greater number of microtubules to form at steady state than did tau 3 or tau 4L. The microtubules generated with each tau isoform had similar steady-state length distributions and were equally susceptible to cold-induced disassembly. These results indicate that the additional microtubule-binding domain in tau 4 enhances microtubule assembly, while the 58-amino-acid insert negates the stimulatory effect of the fourth microtubule-binding domain.  相似文献   
4.
OBJECTIVE: Accelerated re-endothelialisation may inhibit the development of restenosis. Basic Fibroblast Growth Factor (bFGF) plays a key role for early proliferative activity in the artery following injury. Therefore, this study was devised to examine the effect of photodynamic therapy (PDT) on post-injury re-endothelialisation in vivo, and bFGF-mRNA expression in endothelial cells (EC) in vitro. MATERIALS AND METHODS: Rat carotid arteries were balloon-injured prior to PDT. Arteries were analysed after 1, 3, 5, 14 and 30 days. Morphometric measurements were undertaken following injection of 0.5% Evans Blue which stains non-endothelialised surfaces only. To identify EC, immunohistochemistry (CD-31) was performed. Proliferation was assessed by fluorescence cell counting. PCR quantification of bFGF-mRNA expression and proliferation were assessed in bovine aortic EC which were plated on isolated, PDT-treated EC-derived extracellular matrix at (12), 24, 48 (72 h). RESULTS: Three days following PDT, arteries displayed significantly increased endothelial lining (p = 0.02), which was more pronounced at 5 (p = 0.03) and 14 days (p = 0.02). At 30 days no relevant differences between PDT and control were noted. EC proliferation on PDT-treated matrix was significantly increased at 24, 48, and 72 h (p = 0.0004), whereas bFGF-mRNA expression was significantly increased at 24 h only (p = 0.007). CONCLUSION: Post-injury PDT appears to accelerate re-endothelialisation. Expression of bFGF-mRNA, however, although increased shortly after PDT, may not be responsible for a constant stimulation of EC proliferation.  相似文献   
5.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved.  相似文献   
6.
A combined LC/RIA procedure is described for the selective determination of dexamethasone (DEX) and its prodrug dexamethasone-21-isonicotinate (DIN) in plasma. The low affinity of the employed dexamethasone antiserum for DIN (cross-reactivity less than 0.5%) allowed the direct determination of DEX in plasma extracts. For the determination of DIN, both substances of interest were separated by LC, the DIN containing fraction was collected, hydrolysed and the generated DEX was consequently assayed by radioimmunoassay. The assay detection limits were 0.1 ng ml-1 for DEX and 0.75 ng ml-1 for DIN. For both substances, inter- and intra-day variabilities (RSDs) were 6 and 12%, respectively.  相似文献   
7.
The prevalence of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) is underestimated and its diagnosis is costly and restricted to specialised sleep laboratories. The frequency component of interbeat interval increment (III) has been proposed as a simple and inexpensive diagnostic tool in OSAHS. In a set of 150 patients with clinically suspected sleep-related breathing disorder, the actual predictive accuracy of the power spectral density of the III of the very low frequencies (%VLFI) was analysed by comparing with the apnoea/hypopnoea index (AHI), as assessed by synchronised polysomnography. OSAHS was defined in 100 patients according to an AHI>or=15 events.h(-1). Receiver operator characteristic curves built for %VLFI confirmed that this variable was able to separate OSAHS positive from OSAHS negative with statistical significance. Using an appropriate threshold (>4%), %VLFI demonstrated a positive predictive value of 80%. Misclassification of false-positive subjects occurred when the patient presented significant sleep discontinuity and sleep fragmentation (sleep fragmentation index>or=50 events.h(-1)) related to insomnia or periodic limb movements. A power spectral density of the interbeat interval increment of very low frequencies>4% allowed correct classification of obstructive sleep apnoea/hypopnoea syndrome when the clinical history suggested sleep-related breathing disorders and when moderate-to-severe cases are considered. Higher power spectral density of the interbeat interval increment of very low frequencies may also indicate disrupted sleep in the absence of clear clinical symptoms of sleep apnoea/hypopnoea syndrome.  相似文献   
8.
We measured somatosensory evoked magnetic fields during median nerve stimulation in 6 normal subjects. We applied multiple dipole models to study the spatiotemporal structure of early somatosensory evoked magnetic fields (SEFs), as well as the number, 3-dimensional location and time activity of their underlying neuronal sources. Two dipole sources were necessary to model the first 40 msec of SEFs explaining 85% of the data variance. Source 1 was located deeper than source 2, showed primarily a tangential orientation, and accounted for a larger part of the variance; source 2 showed no consistent orientation across subjects. Both sources showed biphasic time activities corresponding to the previously described N20-P30 and P25-N35 components. Spatiotemporal modeling could identify sources which could not be modeled consistently above noise by single moving dipoles (P25 component), revealed small latency differences of the two sources in some subjects suggesting parallel activation of these sources, and allowed separation of sources overlapping considerably both in space and time. We conclude that spatiotemporal modeling of SEFs may be useful to study functional anatomy of human sensorimotor cortex non-invasively.  相似文献   
9.
Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells.  相似文献   
10.
The temporal courses of dipeptidyl peptidase IV gamma-glutamyltransferase and alanine aminopeptidase were followed over 70 days in the morning urine of 15 healthy persons. Subsequent to basic statistical analysis a two-step procedure was performed, including spectral analysis and the fit of a cosine function by non-linear regression. The excretion of the 3 enzymes followed an infradian biorhythm with a mean period length of 10.04 for dipeptidyl peptidase IV, 13.34 for gamma-glutamyltransferase and 10.17 for alanine aminopeptidase. In addition to the basic rhythmic process described by the fitted cosine functions, in most of the enzyme patterns steap peaks of very high excretory activity appeared which was verified in repeated measurements. These infradian biorhythms with changes in the range of 100% and more, as well as their interindividual variations, have to be considered in assessing the excretion of enzymes.  相似文献   
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