Extended HLA profile of an inbred isolate: The Schmiedeleut Hutterites of South Dakota

HLA-A, -B, -C, -DR, and -DQ typings of the Schmiedeleut Hutterites of South Dakota were collected as part of an ongoing genetic-epidemiologic study of HLA and fertility. A total of 1,082 individuals, including 852 married adults representative of the reproductive population of this isolate, were characterized for five-locus HLA haplotypes. HLA-A1, A2, A3, and A24 accounted for 75% of observed HLA-A alleles and HLA-B27, B35, B51, and B62 accounted for 55% of observed HLA-B alleles. S-leut Hutterites are derived from 68 or fewer ancestors. However, only 48 ancestral HLA haplotypes were observed and nine of these accounted for over 52% of the observed haplotypes. Measures of two-locus linkage disequilibrium derived from these haplotypes indicated that one-third to half of the observed HLA-A/B, B/DR, and A/DR allele combinations exhibited highly statistically significant linkage disequilibrium. Allele and haplotype frequencies did not differ between males and females. Recombination rates of 0.004% and 0.005% between HLA-A and -C and between HLA-B and -DR, respectively, were observed. This HLA profile points out a paucity of HLA alleles and haplotypes in this population and marked linkage disequilibrium among the HLA alleles that are present. © Wiley-Liss, Inc.     

The G-protein-coupled receptor kinases beta ARK1 and beta ARK2 are widely distributed at synapses in rat brain.

The beta-adrenergic receptor kinase (beta ARK) phosphorylates the agonist-occupied beta-adrenergic receptor to promote rapid receptor uncoupling from Gs, thereby attenuating adenylyl cyclase activity. Beta ARK-mediated receptor desensitization may reflect a general molecular mechanism operative on many G-protein-coupled receptor systems and, particularly, synaptic neurotransmitter receptors. Two distinct cDNAs encoding beta ARK isozymes were isolated from rat brain and sequenced. The regional and cellular distributions of these two gene products, termed beta ARK1 and beta ARK2, were determined in brain by in situ hybridization and by immunohistochemistry at the light and electron microscopic levels. The beta ARK isozymes were found to be expressed primarily in neurons distributed throughout the CNS. Ultrastructurally, beta ARK1 and beta ARK2 immunoreactivities were present both in association with postsynaptic densities and, presynaptically, with axon terminals. The beta ARK isozymes have a regional and subcellular distribution consistent with a general role in the desensitization of synaptic receptors.     

Use of calcium alginate to pack abscess cavities: a controlled clinical trial.

Many conventional dressings are painful when removed, and may be detrimental to healing. In a pilot study ten consecutive abscesses, requiring incision and drainage, were packed with a calcium alginate dressing: this was well tolerated, its removal causing minimal pain. No adverse effects were attributable to its use. A controlled trial was therefore carried out to compare calcium alginate with the more traditional saline-soaked gauze for packing abscess cavities, following incision and drainage. Patients were randomized to receive either calcium alginate (16 patients) or gauze dressing (18 patients). At the first dressing change the patient marked on a linear analogue scale the pain experienced; the nurse noted similarly the ease of removal of the dressing. Calcium alginate was significantly less painful to remove after operation (P less than 0.01), and also easier to remove (P less than 0.01) than gauze dressings. If abscess cavities are packed after incision and drainage, calcium alginate appears to be an improvement on conventional dressings.     

Detection and partial purification of a potent mitogenic factor for human thyroid follicular cells.

Normal adult human thyroid follicular cells have an extremely limited proliferative capacity in vitro. No previously studied mitogen, including thyrotropin (TSH) or epidermal growth factor (EGF), has in our hands resulted in a significant improvement over the 3-4% nuclear [3H]thymidine pulse-labelling index (LI) obtainable with 10% fetal calf serum. Here we report the detection in the conditioned medium from a sub-clone of NIH3T3 fibroblasts of a mitogenic activity capable of increasing this response up to 10-fold, to an LI of over 20%, together with an even greater relative stimulation of mitotic activity. Preliminary characterisation has excluded EGF and TGF alpha, and demonstrated that the activity is bound reversibly by heparin-Sepharose, thus pointing to a member of the heparin-binding fibroblast- or hepatocyte-growth factor families. This material should have wide practical application in facilitating primary culture of follicular cells, and may reveal new mechanisms of stromal-epithelial interaction regulating normal and neoplastic thyroid growth in vivo.     

The minimum concentration of fibrinogen needed for platelet aggregation using ADP.

OBJECTIVE: Determine the minimum concentration of plasma fibrinogen needed to stimulate the aggregation of platelets, collected from normal subjects, using ADP. DESIGN: Platelet rich plasmas (300 x 10(9) platelets/L) were made and adjusted to final fibrinogen concentrations of 75, 19, 5, and 0 mg/dL using fibrinogen free serum. Each fibrinogen concentration in all twelve subjects was aggregated with ADP SETTING: Research laboratory in the Department of Clinical Laboratory Science at Saint Louis University. PARTICIPANTS: Twelve healthy volunteers of both genders, between the ages of 18 and 60 years who were not pregnant and weighed at least 110 pounds were included in the study. Subjects were excluded from the study if they had ingested aspirin within one week prior to blood collection. In addition, subjects with a history of bleeding disorders such as afibrinogenemia, hypofibrinogenemia, von Willebrand disease, and Bernand-Soulier disease were rejected from the study. MAIN OUTCOME MEASURES: Platelet aggregation tracings were analyzed for amplitude and compared across plasma fibrinogen concentrations. In addition, the type of curve (monophasic vs. biphasic), smoothness and aggregation stability were also noted. RESULTS: The results show that aggregation occurred with every dilution of fibrinogen tested and that the amplitude of the aggregation curves appears not to be dependent on plasma fibrinogen. CONCLUSIONS: The results indicate that platelets from healthy individuals previously exposed to normal fibrinogen levels will aggregate equally well in decreasing plasma fibrinogen concentrations and even in the absence of plasma fibrinogen using ADP as the aggregator.     

Cloning and expression of SLC1OA4,a putative organic anion transport protein

AIM:To determine if novel bile acid transporters may be expressed in human tissues.METHODS:SLC10A1 (NTCP) was used as a probe to search the NCBI database for homology to previously uncharacterized ESTs. The homology search identified an EST (termed SLC10A4) that shares sequence identity with SLC10A1 and SLC10A2 (ASBT). We performed Northern blot analysis and RT-PCR to determine the tissue distribution of SLC10A4. SLC10A4 was cloned in frame with an epitope tag and overexpressed in CHO cells to determine cellular localization and functional analysis of bile acid uptake.RESULTS:Northern analysis revealed that SLC 10A4 mRNA is ubiquitously expressed fn human tissues with the highest levels of mRNA expression in brain,placenta, and liver. In SLC10A4-transfected CHO cells,immunoblotting analysis and immunofluorescence staining demonstrated a 49-kDa protein that is expressed at the plasma membrane and intracellular compartments.Functional analysis of SLC10A4 showed no significant taurocholate uptake in the presence of sodium when compared to untransfected CHO cells.CONCLUSION:To date, we have shown that this protein has no capacity to transport taurocholate relative to SLC1041; however, given its ubiquitous tissue distribution, it may play a more active role in transporting other endogenous organic anions.     

Complications of the cardiopulmonary stress test in patients with depressed left ventricular systolic function.

BACKGROUND: The exercise test has a recognized lower risk of complications when used in the general population and in coronary artery diseased patients, but from a theoretical point of view should have a higher rate of complications when performed in patients with chronic heart failure (CHF). AIMS: To characterize and assess the type and incidence of complications during cardiopulmonary stress test (CPX) in patients with depressed left ventricular systolic function in comparison with a group of patients and individuals with normal function. METHODS: Retrospective analysis of the 334 consecutive CPX performed for risk stratification in 198 patients with a left ventricular ejection fraction below 40% (Group A) and 180 consecutive CPX performed in 78 subjects with normal function (Group B). The two groups were compared with respect to demographic data, CPX parameters and specific complications. Results: Major complications during the tests occurred only in 14 tests of Group A (4.2%, p = 0.012). Non-sustained ventricular tachycardia, <6 beats, occurred in 7 group A and 2 group B tests. The absence of coronary artery disease was the only independent predictor for complications. CONCLUSIONS: Major CPX complications occurred only in patients with impaired left ventricular systolic function. Heart failure patients showed a low probability (around 4%) for complications during CPX, significantly higher and more severe than the risk in the group of patients with normal ventricular function, allowing us to recommend that CPX in patients with heart failure should be performed in a hospital setting under the supervision of a physician with specific training.