Multiple pathways of angiotensin I conversion and their functional role in the canine penile corpus cavernosum

Multiple pathways of angiotensin (Ang) I conversion and their functional role in the canine penile corpus cavernosum were investigated. Biochemical analysis revealed high activities of angiotensin-converting enzyme (ACE) (6.9 +/- 1.7 mU/mg of protein, mean +/- S.E.M., n = 8) and chymase-like enzyme (4.0 +/- 1.4 mU/mg of protein). Functional recording of isometric tension showed that Ang I (3 x 10(-7) M) induced a tension of 0.17 +/- 0.05 g (n = 5), which was reduced to about 60% by pretreatment with an ACE inhibitor, lisinopril (10(-6) M), and almost completely blocked by lisinopril in combination with a chymase inhibitor, chymostatin (10(-4) M). Binding sites for ACE and Ang II receptors were studied by in vitro autoradiography using 125I-351A and 125I-[Sar1, Ile8]Ang II as ligands, respectively. Dense binding of ACE appeared in the endothelial layer of the corpus cavernosum penis, and Ang II receptors were localized in the trabecular smooth muscle layer. An AT1 receptor antagonist, CV-11974 (10(-6) M), markedly displaced 125I-[Sar1, Ile8]Ang II bindings, indicating that the corpus cavernosum penis contains AT1 receptors exclusively. Immunohistochemical studies demonstrated ACE in the endothelium of the corpus cavernosum penis. Mast cells that produce chymase were present mainly in the cavernosal area. These results demonstrate that chymase, in addition to ACE, is involved in the contraction of canine penile corpus cavernosum through local Ang II formation.

Pharmacodynamic comparison of optimal platelet reactivity by multiple platelet function tests in Korean acute coronary syndrome patients with half-dose ticagrelor or prasugrel treatment

Background

East Asians treated with potent P2Y12 inhibitors, prasugrel or ticagrelor exhibit more potent platelet inhibition than clopidogrel. Whether half-dose de-escalation strategy would improve optimal platelet reactivity at maintenance in East Asian patients with acute coronary syndrome (ACS) remains uncertain.

Method

In de-escalation strategy single center study, eligible Korean ACS patients (n=96) were assigned to receive standard-dose ticagrelor (n=33), prasugrel (n=28), followed by half-dose reduction at 1 month for maintenance, and clopidogrel (n=35) as control. Platelet reactivity was measured by VerifyNow, light transmittance aggregometry (LTA) and multiple electrode aggregometry (MEA). The investigators aim to compare optimal platelet reactivity status (OPR, defined as 85–208 P2Y12 reaction unit [PRU] for VerifyNow (VN), 16%–47% for LTA and 19–46 U for MEA) among 3 different platelet function tests at 3 months post PCI.

Results

At 3 months, ticagrelor achieved significantly lower PRU (17 [6–51] vs. 95 [61–151] vs. 172 [111–204]) than prasugrel and clopidogrel, resulting OPR rate 10% vs. 57.7% vs. 60.0%, respectively. Similar results were observed at LTA method (2% [0–12] in ticagrelor vs. 18% [13–22] in prasugrel vs. 18% [11–30] in clopidogrel), with OPR rate 11.8% vs. 69.2% vs. 50.0%, respectively. However, platelet reactivity was similar by MEA method (16 [13–20] in ticagrelor vs. 17 [13–22] in prasugrel vs. 19 [14–28] in clopidogrel), with OPR rate 33.3% vs. 40.0% vs. 42.0%, respectively (all p>0.005). Among the three tests, resulting higher correlation between VN and LTA (r=0.745), MEA and LTA vs. MEA and VN showed lower correlations (r=0.412 and r=0.303). (Fig.)

Conclusion

In Korean ACS patients with half-dose de-escalation strategy after 1 month, OPR rate in ticagrelor is still rare during 3-month treatment by VN and LTA methods, however, prasugrel appears comparable to clopidogrel. VN/LTA might overestimate platelet function than MEA or MEA underestimate OPR rate than VN/LTA.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): National Research Foundation of Korea

Elevated expression of Bcl-X and reduced Bak in primary colorectal adenocarcinomas

Expression of several members of the BCL-2 family of genes was investigated by immunohistochemical methods in 30 primary colorectal adenocarcinomas and 24 adenomatous polyps. When compared to the intensity observed in adjacent normal mucosal epithelial cells, the intensity of Bcl-X immunostaining was elevated in 18 of 30 (60%) carcinomas (P = 0.0001) and 12 of 24 (50%) adenomatous polyps (P = 0.0001). Immunoblot analysis of five pairs of tumors and adjacent normal colonic tissue indicated marked elevations in the relative levels of the anti-apoptotic Bcl-XL, protein in all cases. In contrast to the increased Bcl-X expression, the intensity of Bcl-2 immunostaining was greater than that of normal colonic mucosa in only 3 of 30 (10%) carcinomas and, in fact, was lower than that of adjacent normal epithelia] cells in 25 (83%) cases (P = 0.0001). Furthermore, the percentage of Bcl-2 immunopositive cells was generally lower in carcinomas than in adenomas (mean +/- SE, 44 +/- 6% versus 73 +/- 5%, respectively; P = 0.001) and in moderately or poorly differentiated tumors than in well-differentiated tumors (39 +/- 6% versus 70 +/- 11%, respectively; P = 0.045). In addition, the proportion of tumors in which the Bcl-2 immunointensity was more than or equal to that of normal colonic mucosa was significantly lower in carcinomas than adenomas (5 of 30 versus 15 of 24, respectively; P < 0.001), suggesting that decreases in Bcl-2 expression represent a later event associated with the progression of colorectal cancers. When compared to that of normal adjacent colonic epithelium, the intensity of Mcl-1 immunostaining was reduced in 20 of 30 (67%) of carcinomas (P = 0.0001) compared to only 1 of 24 adenomas, suggesting that decreases in Mcl-1 expression represent a later event associated with progression from a benign to a malignant phenotype or with transition to a less-differentiated state, because most of the carcinomas evaluated here (25 of 30; 83%) were not well differentiated. The intensity of immunostaining for the pro-apoptotic protein Bak was reduced compared to that of normal mucosal epithelial cells in 27 of 30 (90%) carcinomas and 22 of 24 (92%) adenomas, suggesting that reductions in Bak expression occur early in colorectal tumor progression (P = 0.0001). In contrast, the intensity of immunostaining for the pro-apoptotic protein Bax was not significantly altered in carcinomas; compared to that of normal colonic mucosa, Bax immunointensity was reduced in only 7 of 30 (23%) carcinomas and 3 of 24 (13%) adenomas, and the percentage of Bax immunopositive cells was also not significantly different in any of the histological subgroups. Taken together, these results suggest that expression of Bcl-XL is increased in undifferentiated primary colorectal cancers, often with accompanying reciprocal decreases in the anti-apoptotic proteins Bcl-2 and Mcl-1 and the pro-apoptotic protein Bak, whereas Bax expression is relatively constant. Thus, a shift from expression of the anti-apoptotic proteins Bcl-2 and Mcl-1 to the Bcl-XL protein may occur during progression of colorectal tumors.

Relationship and prognosis of hospho-Akt and CD44v6 in breast cancer

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Background: The purpose of this study was to investigate the relationship between pAkt and CD44v6 expression of breast cancer after surgery. We also evaluated the expression patterns and predictive value of pAKT and CD44v6 in breast cancer tissues. Methods: Expression of pAkt and CD44v6 protein was detected using immunohistochemistry in 98 patients. The correlation between the expression of pAkt, CD44v6, and other disease-related characteristics with treatment outcome was investigated. Kaplan-Meier survival analysis and Cox regression were used to observe the correlation between variables and the prognostic value. Results: Of all these 98 cases, 37 cases (37.8%) were observed as positive for pAkt expression, and there were 25 cases (51.0%) pAKT positive expression in the lymph node (+) and 15 (30.6%) in lymph node (-) of 49 cases. pAkt expression had no significant difference in node-positive group and node-negative group. We examined the relationship between pAKT and HER2 expression, pAkt expression was positively correlated with HER-2 expression (p = 0.009). A statistically significant difference in positive staining for pAkt was observed between CD44V6-positive and CD44V6-negative tumors (p = 0.016). CD44v6 positive tumors showed a statistically very highly significant association between node-positive and node-negative (p = 0.013). For prognosis value, a week relationship was observed between pAkt and OS, but DFS was inversely associated with pAkt staining intensity (p = 0.061, p = 0.004). There had a statistical correlation between CD44v6 overexpression and OS and DFS (p = 0.026 and 0.006 respectively). Univariate analysis revealed that lymph node status and CD44V6 were significantly associated with decreased OS and DFS, but there had no significant difference between variables and OS and DFS by multivariate analysis. Conclusions: Our data suggested that there had a intensive relationship between pAKT and CD44v6 expression in breast cancer tissues. We demonstrated that both pAkt and CD44v6 were significantly assiociated with a decreased OS and DFS in breast cancer patients. pAKT and CD44v6 overexpressed in cancer cells may be sensitive markers for predicting the treatment outcome in breast cancer patients.

No significant financial relationships to disclose.

[Observation of EGG parameters during -6 degrees head-down bedrest for 21 days]

Electrogastography (EGG) was recorded in 15 healthy volunteers before and after meal during 21 days head down tilt -6 degrees bed rest. The results showed that nausea, distension and pain in the abdomen and loss of appetite appeared at the beginning of bed rest and body weight decreased significantly (P < 0. 01) after bed rest; Low frequency (Bradygastria) proportion of EGG (<2.4cpm) increased apparently after 8 days of bedrest, and there was significant difference (P <0.05) between preprandial and postprandial bradygastria. The dynamic parameters of bradygastria declined significantly and the rhythm of bradygastria increased with duration of bedrest. It indicates that simulated weightlessness may cause decrease of gastric rhythm and gastric motility.

Thermoluminescence of PbWO4 irradiated with UV light

PbWO4 single crystals were grown by the Czochralski method in argon and air. The glow curves induced by UV light and the absorption spectra of PbWO4 annealed at various temperatures were measured. The glow curves of PbWO4 were strongly dependent on the growing atmospheres. The activation energies of the 110 K peak of PbWO4 grown in argon and the 122 K peak of PbWO4 grown in air were calculated to be 0.23 eV and 0.29 eV, respectively. The ratio of the 2.76 eV emission band to the 2.48 eV or 2.26 eV emission bands of the PbWO4 grown in air was smaller than that of the PbWO4 grown in argon. The glow curve of PbWO4 grown in argon was similar to that of PbWO4 grown in air when the annealing temperatures were increased.

Cotton liners to mediate glove comfort for greenhouse applicators

Greenhouse applicators' acceptance of cotton knit gloves worn as liners under nitrile chemical-resistant gloves (CRG) for pesticide application was investigated through a wear study in Iowa and New York. Comfort was assessed by questionnaires and interviews with 10 applicators. Contamination levels of four pesticides on CRG and liners at thumb, forefinger, palm, and cuff locations were determined by chemical analysis using high-performance liquid chromatography or gas chromatography. Applicators reported feeling more comfortable with cotton liners under their CRG than without and that cotton liners were easy to manage. Contamination was significantly greater on nitrile CRG than on cotton liners underneath, but a few liner specimens had measurable contamination. No significant contamination differences were found between right- and left-hand gloves. Contamination varied significantly by hand location, with cuffs least, and by pesticide, with chlorpyrifos most. These results support the Environmental Protection Agency's recommendation that liners should be disposable, but further work on liners and their laundering feasibility seems indicated.

Reliability of synthetic diffusion-weighted imaging with a high b-value for paediatric abdominal MRI

AIM

To evaluate the reliability of synthetic diffusion-weighted imaging (DWI) using a high b-value in comparison to conventional DWI for paediatric abdominal MRI.

MATERIALS AND METHODS

Paediatric patients (<19 years old) who underwent liver or pancreatobiliary MRI with DWI using 10 b-values (b = 0, 25, 50, 75, 100, 200, 400, 600, 800, 1,500 s/mm2) from March to October 2021 were included in this retrospective study. Using the software, synthetic DWI using b = 1,500 s/mm2 was generated automatically by selecting the b-value required as output. Conventional and synthetic DWI values for b = 1,500 s/mm2 were measured at the liver, spleen, paraspinal muscle, and mass lesions, if present, and apparent diffusion coefficient (ADC) values were calculated using the mono-exponential model. Intraclass correlation coefficients (ICCs) were calculated to assess the reliability of conventional and synthetic DWI and ADC values with b = 1,500 s/mm2.

RESULTS

Thirty paediatric patients (M:F = 22:8, mean 10.8 ± 3.1 years old) were included and four had tumours on abdominal MRI. ICC values were 0.906-0.995 between conventional and synthetic DWI and ADC with b = 1,500 s/mm2 in the liver, spleen and muscle. For mass lesions, ICC values were 0.997-0.999 for both synthetic DWI and ADC images.

CONCLUSIONS

Synthetic DWI and ADC values obtained using a high b-value showed excellent agreement with conventional DWI for the liver, spleen, muscle, and mass in paediatric MRI.

Gene structure of the human DDX3 and chromosome mapping of its related sequences

The human DDX3 gene (GenBank accession No. U50553) is the human homologue of the mouse Ddx3 gene and is a member of the gene family that contains DEAD motifs. Previously, we mapped the gene to the Xp11.3-11.23. In this report, we describe the structural organization of the human DDX3 gene. It consisted of 17 exons that span approximately 16 kb. An Alu element was present in the intron 13. Its organization was the same as that of the human DBY gene, a closely related sequence present on the Y chromosome. We also identified two processed pseudogenes (DDX3) with a sequence that is highly homologous to those of DDX3 cDNAs, but contain a translation termination codon within its open-reading frame. Pseudogenes are mapped on human chromosomes 4 and X, respectively. In this paper, we discuss the relationships between DDX3 and its related sequences that have been isolated.

Comparative study of conventional hip-knee-ankle-foot orthoses versus reciprocating-gait orthoses for children with high-level paraparesis

We evaluated eight children with thoracic or high lumbar-level paraparesis for metabolic performance while ambulating with custom fabricated thermoplastic hip-knee-ankle-foot orthoses (HKAFOs) and reciprocating-gait orthoses (RGOs). Seven of the eight children had myelomeningocele. Each patient was tested in both systems at self-selected speeds in a crossover study design. At self-selected speeds, the level of exercise intensity for both thoracic and high-lumbar patients with either orthosis was lower than that for normal children. The average metabolic cost of walking in the RGO was twice that of normal children, as compared with six times normal in HKAFOs. For the four thoracic-level patients, there was a significantly higher oxygen cost of ambulation in using HKAFOs versus RGOs. No significant difference in metabolic performance was found for the high-lumbar patients. Velocity of ambulation was faster in the RGOs than in the HKAFOs. For thoracic-level patients, our data suggest that an RGO will provide a faster, more energy-efficient gait than a statically locked HKAFO. For high-lumbar patients, no significant difference was found between the two orthoses. Seven of eight children preferred the RGO over the HKAFO.