Stress concentration in adhesively bonded joints, which is considered a major factor affecting their strength, can be avoided by tailoring the material properties of the adhesives using a ...functionally graded adhesive (FGA). The material properties of second-generation acrylic (SGA) adhesives can be simply changed by changing the mixing ratio of the agents. However, the superiority of FGA joints using SGA adhesives has not been experimentally clarified yet. Therefore, in this study, a shear strength test and a constant load low-cycle shear test were conducted on single lap joint (SLJ) specimens tailoring the adhesive layer stepwise. The FGA specimen was compared with the non-tailored specimens using stiff or flexible adhesives. The SLJ test results showed 16% improvement in the joint strength by stepwise tailoring of the adhesive layer. Additionally, the difference in the strain distributions among the different adhesive layers was investigated via a digital image correlation (DIC) method, and the shear strain at the edge of the FGA specimen was more than 40% decreased compared to the non-tailored specimen using the flexible adhesive. The low-cycle test results also showed the superiority of the FGA specimen to the other specimens. The FGA specimen held up more than 4 times the number of cycle of other specimens with an applied load of 18 kN or more. This was attributed to the suppressed plastic deformation at the edges of the adhesive layer owing to the introduction of FGAs.
A method for fabricating adhesively bonded joints with graded properties along the bond-line was proposed. By utilizing two types of acrylic adhesives, one hard and the other soft, the properties of ...the mixture were changed by controlling the mixing ratio. An applicator for the adhesives was developed and used for the experiments, in which property-graded adhesive layers were actually produced. The properties, i.e., stress-strain curves at various points of the property-graded adhesive layer, were experimentally measured, and the validity of the proposed method was confirmed. The Young's moduli at multiple points of the adhesive layer changed from 34.7 MPa to 634 MPa by changing the mixing ratio of the adhesives.
(
) is one of the most treacherous pathogens among those causing hospital-acquired pneumonia (HAP).
possesses an adaptable physiology, seen not only in its antibiotic resistance and virulence ...phenotypes but also in its metabolic versatility. In this study, we observed that
undergoes global transcriptional changes in response to human pleural fluid (PF), a key host-derived environmental signal. Differential gene expression analyses combined with experimental approaches revealed changes in
metabolism, affecting cytotoxicity, persistence, bacterial killing, and chemotaxis. Over 1,220 genes representing 55% of the differentially expressed transcriptomic data corresponded to metabolic processes, including the upregulation of glutamate, short chain fatty acid, and styrene metabolism. We observed an upregulation by 1.83- and 2.61-fold of the pyruvate dehydrogenase complex subunits E3 and E2, respectively. We also found that pyruvate (PYR), in conjunction with PF, triggers an
pathogenic behavior that adversely impacts human epithelial cell viability. Interestingly, PF also amplified
cytotoxicity against murine macrophages, suggesting an immune evasion strategy implemented by
. Moreover, we uncovered opposing metabolic strategies dependent on the degree of pathogenicity of the strains, where less pathogenic strains demonstrated greater utilization of PYR to promote persister formation in the presence of PF. Additionally, our transcriptomic analysis and growth studies of
suggest the existence of an alternative phenylalanine (PA) catabolic route independent of the phenylacetic acid pathway, which converts PA to phenylpyruvate (PP) and shuttles intermediates into styrene metabolism. This alternative route promoted a neutrophil-evasive state, as PF-induced degradation of PP significantly reduced overall human neutrophil chemotaxis in
chemotactic assays. Taken together, these data highlight
pathoadaptabililty in response to host signals and provide further insight into the role of bacterial metabolism in virulence traits, antibiotic persistence strategies, and host innate immune evasion.
Acinetobacter baumannii is a feared, drug-resistant pathogen, characterized by its ability to resist extreme environmental and nutrient-deprived conditions. Previously, we showed that human serum ...albumin (HSA) can increase foreign DNA acquisition specifically and alter the expression of genes associated with pathogenicity. Moreover, in a recent genome-wide transcriptomic study, we observed that pleural fluid (PF), an HSA-containing fluid, increases DNA acquisition, can modulate cytotoxicity, and control immune responses by eliciting changes in the A. baumannii metabolic profile. In the present work, using more stringent criteria and focusing on the analysis of genes related to pathogenicity and response to stress, we analyzed our previous RNA-seq data and performed phenotypic assays to further explore the impact of PF on A. baumannii's microbial behavior and the strategies used to overcome environmental stress. We observed that PF triggered differential expression of genes associated with motility, efflux pumps, antimicrobial resistance, biofilm formation, two-component systems (TCSs), capsule synthesis, osmotic stress, and DNA-damage response, among other categories. Phenotypic assays of A. baumannii A118 and two other clinical A. baumannii strains, revealed differences in their responses to PF in motility, biofilm formation, antibiotic susceptibility, osmotic stress, and outer membrane vesicle (OMV) production, suggesting that these changes are strain specific. We conclude that A. baumannii's pathoadaptive responses is induced by HSA-containing fluids and must be part of this bacterium armamentarium to persist in hostile environments.
Objectives To evaluate the clinical utility of transrectal power Doppler imaging (PDI) of the prostate for detecting prostate cancer in patients with abnormally high serum levels of prostate specific ...antigen (PSA).
Patients and methods Patients (107) with abnormally high serum PSA levels were assessed using a digital rectal examination (DRE), transrectal ultrasonography (TRUS) and PDI. Any hypervascular lesion on PDI was graded on a scale of 0–3, where grade 1–3 was considered positive and grade 0 negative. Patients were then diagnosed by prostatic needle biopsy and the results compared with the other detection methods.
Results Needle biopsy confirmed prostate cancer in 41 (24%) of the 170 patients. PDI was positive in 68, of whom 40 (59%) had prostate cancer; all those but one having prostate cancer were positive on PDI. Thus, PDI had a high sensitivity of 98% (40/41) and a negative predictive value of 99% (101/102). PDI could have saved a significant number of patients from undergoing unnecessary biopsies, compared with DRE and TRUS (P < 0.001).
Conclusion The use of PDI in detecting prostate cancer might reduce the number of unnecessary needle biopsies of the prostate in patients with abnormally high serum PSA levels.
OBJECTIVES
To assess the effects of giving chlormadinone acetate (CMA) before surgery on blood loss associated with transurethral resection of the prostate (TURP), in a prospective randomized ...controlled study.
PATIENTS AND METHODS
Candidates for TURP among patients with benign prostatic hyperplasia were randomized to either treatment with CMA (CMA+) or not (CMA−). In principle, CMA was started at least 28 days before TURP and continued until just before surgery.
RESULTS
In all, 33 patients in the CMA+ (median duration of treatment 34.5 days) and 38 in the CMA− group were evaluable. The mean blood loss during TURP was less in the CMA+ (237.3 mL) than in the CMA− group (263.1 mL), but the difference was not significant. There was significantly less blood loss per gram of resected prostate tissue in the CMA+ (9.6 mL/g) than in the CMA− group (13.3 mL/g) (P < 0.05). Haematuria on the day of and the day after TURP was also significantly less severe in the CMA+ than in the CMA− group (P < 0.001 and P < 0.05, respectively). The mean microvessel density of resected prostate tissue was significantly less after CMA treatment (P < 0.001).
CONCLUSIONS
CMA given for 1 month before TURP could reduce blood loss to some extent during and after TURP, and this may be related to a decrease in microvessel density.
Objectives. To reveal the possible use of transrectal power Doppler imaging (PDI) of the prostate in the assessment of the microvascular density (MVD) of cancer lesions.
Methods. In 22 patients with ...clinically organ-confined prostate cancer, PDI was performed before radical prostatectomy and the degree of vascularity of the cancer lesions as evaluated by PDI was compared with the MVD determined on the surgical specimens. The vascularity by PDI of each cancer lesion was graded on a scale of DS0 to DS2, according to the degree of Doppler signal accumulation. MVD was obtained using factor VIII immunohistochemistry.
Results. The vascularity of the PDI of 46 cancer lesions categorized 23 (50%), 10 (22%), and 13 (28%) cancer lesions as DS0, DS1, and DS2, respectively. Significant differences were found in the MVD between DS0 (46.6 ± 26.8) and DS2 (89.0 ± 18.1,
P <0.005) lesions and between DS1 (50.9 ± 25.4) and DS2 (
P <0.001) lesions. The MVD of 30 cancer lesions in 13 patients without neoadjuvant therapy was significantly higher than that of the 16 lesions in 9 patients with therapy (70.2 ± 28.2 versus 39.5 ± 23.9,
P <0.001). In the 13 patients without neoadjuvant therapy, the MVD of the DS2 lesions (89.1 ± 18.9) was significantly higher than that of the DS0 lesions (59.3 ± 32.5,
P <0.01) and DS1 lesions (55.9 ± 20.9,
P <0.005).
Conclusions. The semiquantitative assessment of Doppler flow signals using PDI appears to be of clinical value as an indicator of MVD.
The present study was conducted to reveal the possible changes in transrectal ultrasonic measurements of the prostate in relation to the degree of rectal wall distension. When analyzed together for ...51 men, all measurements but area changed statistically significantly as the rectal wall was distended by a balloon covering a probe. Ultrasonic measurements concerning the prostatic shape changed more remarkably than those concerning its size. More importantly, changes in ultrasonic measurements were much more remarkable in patients with a healthy prostate than in those with an advanced BPH. These results suggest that possible changes in prostatic shape with the rectal wall distension has to be taken into account when evaluating transrectal prostatic ultrasonograms in terms of changes in shape, especially in patients with a healthy prostate. This is also the case when the diagnosis of BPH is made based on the change in shape, such as presumed circle area ratio, which is a parameter representing the roundness of the horizontal sonogram of the prostate.
The possibility of using transrectal power Doppler imaging (PDI) of the prostate for assessing the microvascular density (MVD) of cancer lesions was examined. The study involved 22 patients with ...clinically organ-confined prostate cancer. PDI was performed prior to radical prostatectomy and the degree of vascularity of cancer lesions evaluated by PDI was compared with MVD determined on surgical specimens.
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