Recognition of Dermabacter hominis, formerly CDC fermentative coryneform group 3 and group 5, as a potential human pathogen.

Thirty strains of fermentative coryneform-like bacteria designated CDC fermentative coryneform group 3 and coryneform group 5 were compared biochemically by cellular fatty acid analysis and by DNA relatedness with the type strain of Dermabacter hominis, ATCC 49369. DNA from 22 strains of both CDC groups showed 69 to 96% relatedness (hydroxyapatite method) to labeled DNA from ATCC 49369 and to DNA from CDC group 3 strain G4964, and the strains are considered to belong to D. hominis. The remaining eight strains were genetically but not phenotypically differentiable from D. hominis. They were genetically heterogeneous, but hybridization results indicated that they probably belong to the genus Dermabacter. Thirteen of the 22 D. hominis strains and all 8 of the other Dermabacter strains had been isolated from blood, which indicates the pathogenic potential of this species and genus.     

Integrin α3β1 can promote adhesion and spreading of metastatic breast carcinoma cells on the lymph node stroma

We have reported that metastatic human melanoma cells utilize the α_vβ₃ integrin to adhere to lymph node vitronectin (VN). In the present study, the adhesion of human and rat breast carcinoma cells to lymph node tissue was analyzed. We have previously shown a correlation between the metastatic potential of breast carcinoma cells and an RGD-mediated adhesion to cryostat sections of peripheral lymph nodes; this adhesion could be blocked by an antibody to the integrin β₁ subunit. Here, we show that the metastatic breast carcinoma cell were significantly more adherent to fibronectin (FN) expressed by lymph node-derived stromal cells than non-metastatic cells. Metastatic cells also spread more rapidly than non-metastatic cells on FN-coated substrates. Using a combination of immunofluorescence microscopy, immunoprecipitation and blocking assays with integrin-specific antibodies, we found (i) that expression of the α₃β₁ integrin on metastatic mammary carcinoma cells was specifically increased in comparison to non-metastatic cells and (ii) that the α₃β₁ receptor was involved in the increased adhesion of metastatic cells to lymph node FN and in cell spreading on FN-coated substrates. Our data also suggest that the α₅β₁ integrin, which is also expressed on the metastatic cells, did not contribute to this increase in adhesion. Our data implicate the α₃β₁ integrin in adhesion to lymph node stromal cell FN and suggest that metastatic cells of different tissue origins (e.g., melanoma and breast carcinoma) may utilize distinct integrin-ligand combinations to colonize the same target organ. © 1996 Wiley-Liss, Inc.     

Stroke in supplementary motor area mimicking functional disorder: a case report

Journal of Neurology - Supplementary motor area, the posterior third of the medial aspect of superior frontal gyrus, is known to be a heterogeneous area in function. It is involved in...     

Low risk of complications in patients with first-time acute uncomplicated diverticulitis

Purpose

First-time acute uncomplicated diverticulitis (AUD) has been considered to have an increased risk of complication, but the level of evidence is low. The aim of the present study was to evaluate the risk of complications in patients with first-time AUD and in patients with a history of diverticulitis.

Methods

This paper is a population-based retrospective study at Västmanland’s Hospital, Västerås, Sweden, where all patients were identified with a diagnosis of colonic diverticular disease ICD-10 K57.0–9 from January 2010 to December 2014. The records of all patients were surveyed and patients with a computed tomography (CT)-verified AUD were included. Complications defined as CT-verified abscess, perforation, colonic obstruction, fistula, or sepsis within 1 month from the diagnosis of AUD were registered.

Results

Of 809 patients with AUD, 642 (79%) had first-time AUD and 167 (21%) had a previous history of AUD with no differences in demographic or clinical characteristics. In total, 16 (2%) patients developed a complication within 1 month irrespective of whether they had a previous history of diverticulitis (P = 0.345). In the binary logistic regression analysis, first-time diverticulitis was not associated with increased risk of complications (OR 1.58; CI 0.52–4.81). The rate of antibiotic therapy was about 7–10% during the time period and outpatient management increased from 7% in 2010 to 61% in 2014.

Conclusions

The risk for development of complications is low in AUD with no difference between patients with first-time or recurrent diverticulitis. This result strengthens existing evidence on the benign disease course of AUD.

     

Influences of history, geography, and religion on genetic structure: the Maronites in Lebanon

Cultural expansions, including of religions, frequently leave genetic traces of differentiation and in-migration. These expansions may be driven by complex doctrinal differentiation, together with major population migrations and gene flow. The aim of this study was to explore the genetic signature of the establishment of religious communities in a region where some of the most influential religions originated, using the Y chromosome as an informative male-lineage marker. A total of 3139 samples were analyzed, including 647 Lebanese and Iranian samples newly genotyped for 28 binary markers and 19 short tandem repeats on the non-recombinant segment of the Y chromosome. Genetic organization was identified by geography and religion across Lebanon in the context of surrounding populations important in the expansions of the major sects of Lebanon, including Italy, Turkey, the Balkans, Syria, and Iran by employing principal component analysis, multidimensional scaling, and AMOVA. Timing of population differentiations was estimated using BATWING, in comparison with dates of historical religious events to determine if these differentiations could be caused by religious conversion, or rather, whether religious conversion was facilitated within already differentiated populations. Our analysis shows that the great religions in Lebanon were adopted within already distinguishable communities. Once religious affiliations were established, subsequent genetic signatures of the older differentiations were reinforced. Post-establishment differentiations are most plausibly explained by migrations of peoples seeking refuge to avoid the turmoil of major historical events.     

A common variant in the CDKN2B gene on chromosome 9p21 protects against coronary artery disease in Americans of African ancestry

A 58 kb region on chromosome 9p21.3 has consistently shown strong association with coronary artery disease (CAD) in multiple genome-wide association studies in populations of European and East Asian ancestry. In this study, we sought to further characterize the role of genetic variants in 9p21.3 in African American individuals. Apparently healthy African American siblings (n = 548) of patients with documented CAD < 60 years of age were genotyped and followed for incident CAD for up to 17 years. Tests of association for 86 single-nucleotide polymorphisms (SNPs) across the 9p21.3 region in a generalized estimating equation logistic framework under an additive model adjusting for traditional risk factors, family, follow-up time and population stratification were performed. A single SNP within the CDKN2B gene met stringent criteria for statistical significance, including permutation-based evaluations. This variant, rs3217989, was common (minor allele (G) frequency 0.242), conveyed protection against CAD (odds ratio (OR) = 0.19, 95% confidence interval (CI): 0.07 to 0.50, P = 0.0008) and was replicated in a combined analysis of two additional case/control studies of prevalent CAD/MI in African Americans (n = 990, P = 0.024, OR = 0.779, 95% CI: 0.626-0.968). This is the first report of a CAD association signal in a population of African ancestry with a common variant within the CDKN2B gene, independent from previous findings in European and East Asian ancestry populations. The findings demonstrate a significant protective effect against incident CAD in African American siblings of persons with premature CAD, with replication in a combination of two additional African American cohorts.     

Modulation of polycaprolactone composite properties through incorporation of mixed phosphate glass formulations

Phosphate-based glasses (PGs) and their composites are of interest as bone repair and tissue engineering scaffolds due to the totally degradable nature of the materials. This study has investigated the effect of Si and Fe on the properties of PG particulate-filled polycaprolactone (PCL) matrix composites. Two glass compositions were investigated (mol.%): 50P₂O₅, 40CaO and 10SiO₂ or Fe₂O₃ (Si₁₀ and Fe₁₀, respectively). All composites contained 40 vol.% particulate filler, either Si₁₀, Fe₁₀, or a blend (40Si₁₀/0Fe₁₀, 30Si₁₀/10Fe₁₀, 20Si₁₀/20Fe₁₀, 10Si₁₀/30Fe₁₀ or 0Si₁₀/40Fe₁₀). Ion release, weight loss and composite mechanical properties were characterised as a function of time in deionised water (DW) and phosphate-buffered saline (PBS), respectively. The potential for calcium phosphate deposition was assessed in simulated body fluid (SBF). Calcium and phosphate ion release in DW increased in tandem with the rate of composite weight loss, which increased with Si₁₀ content. A Si₁₀ content dependent rate of pH reduction was observed in DW. After 56 days the PG in the 40Si₁₀/0Fe₁₀ composite was completely dissolved, whereas 67% of that in the 0Si₁₀/40Fe₁₀ composite remained. The initial flexural strength of 40Si₁₀/0Fe₁₀ composites was significantly lower when compared with the other materials. An increase in Si₁₀ content led to an increase in Young’s modulus and a concomitant decrease in flexural strain. It was found that the PCL molecular weight (M_w) decreased dramatically with increasing Si₁₀ content. FTIR analysis showed that Si incorporation into PG led to reaction with the PCL ester bonds, resulting in a reduction in PCL M_w when processed at elevated temperatures. Changes in mechanical properties with time in PBS were glass blend dependent and a more rapid rate of reduction was observed in higher Si₁₀ content composites. After 28 days in SBF surface deposited brushite was formed in 20Si₁₀/20Fe₁₀ PG containing composites. Thus, the properties of PCL–PG composites could be tailored by controlling the phosphate glass blend composition.