The interaction of sex and age on outcomes in emergency medical services-treated out-of-hospital cardiac arrest: A 5-year multicenter retrospective analysis.

Background: Studies have established that sex and age influence outcomes following out-of-hospital cardiac arrest (OHCA). However, a knowledge gap exists regarding their interaction. This study aimed to investigate the interaction of age and sex and how they cooperatively influence OHCA outcomes. Methods: This retrospective cohort study included adult, nontraumatic OHCA patients admitted to a university hospital and its affiliated hospitals in Taiwan from January 2017 to December 2021. Data including sex, age, body mass index, cardiac rhythm, and resuscitation information in the emergency department (ED) were collected from medical records. The study outcomes encompassed survival to intensive care unit (ICU) admission, survival to hospital discharge, and a favorable neurological outcome. Multivariable logistic regression was performed to estimate the influence of sex on study outcomes. Results: We analyzed a total of 2,826 eligible subjects categorized into three groups: young (18-44 years, 149 males and 57 females), middle-aged (45-64 years, 524 males and 188 females), and old (≥65 years, 1,049 males and 859 females). Analysis of the effects of sex according to age stratification showed that old males had higher odds for survival to ICU admission (OR: 1.49, 95% CI: 1.21-1.83) and favorable neurological outcomes (OR: 2.74, 95% CI: 1.58-4.76) than did old females. Analysis of the effects of age according to sex stratification revealed that old males had lower odds for survival to hospital discharge (OR: 0.33, 95% CI: 0.21-0.51) and favorable neurological outcomes (OR: 0.26, 95% CI: 0.16-0.43) than did young males. Old females also showed the same trend as males, with lower odds for survival to hospital discharge (OR: 0.37, 95% CI: 0.17-0.78) and favorable neurological outcomes (OR: 0.11, 95% CI: 0.05-0.25) than did young females. Conclusions: The interaction between sex and age in patients with OHCA results in diverse outcomes. Within the same sex, age demonstrated varying effects on distinct outcomes.

Colonic Diverticulitis Location Affects the Diagnostic Accuracy of Point-of-Care Ultrasound: A Multicenter, 10-Year Study.

OBJECTIVE: Point-of-care ultrasound (PoCUS) has high sensitivity and specificity in diagnosing uncomplicated colonic diverticulitis in Western patients. Evidence regarding the accuracy of PoCUS in Asian patients in which diverticulitis frequently occurs in the right-side colon is lacking. This multicenter, 10-y study was aimed at evaluating the diagnostic accuracy of PoCUS in various locations of uncomplicated diverticulitis among Asians. METHODS: A convenience sample of patients with suspected colonic diverticulitis who had undergone computed tomography (CT) were eligible. Patients undergoing PoCUS before CT were included. The primary outcome was the diagnostic accuracy of PoCUS in the various locations, compared with the final diagnosis made by the expert physicians. The sensitivity, specificity, positive predictive value and negative predictive value were computed. The logistic regression model was used to investigate the possible factors related to the accuracy of PoCUS. RESULTS: A total of 326 patients were included. The overall accuracy of PoCUS was 92% (95% confidence interval [CI]: 89.1%-95.0%) and was lower in the cecum (84.3%, 95% CI: 77.8%-90.8%), compared with other locations (p < 0.0001). Nine of 10 false positives had the final diagnosis of appendicitis: 5 had an outpouching structure whose origin in the cecum could not be traced and 4 had elongated "diverticula." Moreover, body mass index was negatively associated with the accuracy of PoCUS in cecal diverticulitis (odds ratio: 0.79, 95% CI: 0.64-0.97) after adjusting for other covariates. CONCLUSION: Point-of-care ultrasound exhibits high diagnostic accuracy in diagnosing uncomplicated diverticulitis in the Asian population. However, the accuracy varies according to location, and was relatively low in the cecum.

Epinephrine administration in adults with out-of-hospital cardiac arrest: A comparison between intraosseous and intravenous route.

INTRODUCTION: The benefits and risks of the intraosseous (IO) route for vascular access in patients with out-of-hospital cardiac arrest (OHCA) remain controversial. This study compares the success rates of establishing the access route, epinephrine administration rates, and time-to-epinephrine between adult patients with OHCA with IO access and those with intravenous (IV) access established by paramedics in the prehospital setting. METHODS: This was a retrospective study conducted by the San-Min station of Taoyuan Fire Department. Data for IV access were collected between January 1, 2020, and December 31, 2020. Data for IO access were collected between January 1, 2021, and March 10, 2021. Inclusion criteria were adult patients with OHCA who received on-scene resuscitation attempts and in whom either IV or IO route access was established by paramedics. Exclusion criteria were missing data, return of spontaneous circulation before establishing vascular access, cardiac arrest en route to hospital, patients not resuscitated, and OHCA unidentified by the dispatcher. Exposure was defined as IV route vs. IO route (EZ-IO®). The outcome measurements were per-patient based success rates of route establishment (successes/attempts), administration rates of epinephrine (epinephrine administered per case/enrolled OHCAs), and odds ratios of IV versus IO on epinephrine administration. We used nonparametric Mann-Whitney rank sum tests for the analysis in continuous variables and Fisher's exact tests for the analysis of categorical variables and the outcomes. Firth logistic regression method was used for sparse data. Factors associated with epinephrine administration other than vascular access were also analyzed. Time-to-epinephrine (defined as time from paramedic arrival to epinephrine injection) was reviewed and calculated by two independent observers and the Kaplan-Meier method was used to compare the two access routes. RESULTS: A total of 112 adult patients were enrolled in the analysis, including 71 men and 41 women, with an average age of 67 years. There were 90 IV access cases and 22 IO access cases. The groups were compared for median success rates of route establishment (33% vs. 100%, P < 0.001) and administration rates of epinephrine (52% vs. 100%, P < 0.001). The adjusted odds ratio of IO versus IV was 32.445, 95% confidence interval (CI) of 1.844-570.861. Time-to-epinephrine was significantly shorter in the cumulative time-event analysis by the Kaplan-Meier method (P < 0.001). CONCLUSION: The IO route was significantly associated with higher success rates of route establishment, epinephrine administration, and shorter time-to-epinephrine in the prehospital resuscitation of adult patients with OHCA.

Rational design of synthetically tractable HDAC6/HSP90 dual inhibitors to destroy immune-suppressive tumor microenvironment.

INTRODUCTION: The tumor microenvironment is mainly flooded with immunosuppressive cells and inhibitory cytokines, resulting in the inability of effective immune cells to infiltrate and recognize tumors and even the loss of anti-cancer ability. OBJECTIVES: We propose a novel HDAC6/HSP90 dual inhibitory strategy as well as a chemoimmunotherapeutic agent that does not only kill tumor cells but also destroys the tumor microenvironment and enhances anti-cancer immunity. METHODS: A hybrid scaffold construction approach was leveraged to furnish a series of rationally designed resorcinol-based hydroxamates as dual selective HDAC6/HSP90 inhibitors. The drug design campaign commenced with a fragment recruitment process to pinpoint validated structural units to inhibit HDAC6 and HSP90, followed by their installation in flexible HDAC inhibitory templates via an efficient and facile multistep synthetic route. Subsequent evaluations identified a strikingly potent selective HDAC6/HSP90 dual inhibitor (compound 17) via molecular and biological analysis in vitro and in vivo. RESULTS: Compound 17 exhibited not only direct cytotoxicity to cancer cells but also downregulated immune checkpoints (PD-L1 and IDO) expression in tumors via the inhibition of STAT1 pathway and degradation of oncogene proteins (Src, AKT, Rb, and FAK), leading to in vivo tumor growth inhibition. These multiple effects enabled the effector T cells to largely infiltrate into the tumor region and release granzyme B to kill cancer cells. In addition, compound 17 also decreased TGF-ß secretion from normal cells, resulting in the systemic reduction of immunosuppressive regulatory T cells. Delightfully, a cocktail treatment of compound 17 and anti-PD-1 antibodies demonstrated synergistic efficacy to eliminate solid tumors with 83.9% of tumor growth inhibition. CONCLUSION: In summary, the impressive activity profile of compound 17, as an effective anticancer agent and a potential immunosensitizer, forecasts the application of HDAC6/HSP90 dual inhibitory strategy to overcome the immunosuppressive tumor microenvironment.

Colonic diverticulitis location is a risk factor for recurrence: a multicenter, retrospective cohort study in Asian patients.

Evidence regarding the recurrence of diverticulitis is limited in Asian patients. This study aims to investigate recurrence rates and identify predictive factors for the recurrence of diverticulitis following successful nonoperative treatment in Asian patients. A multicenter, retrospective cohort study was conducted between 2012 and 2018. Adult patients with computed tomography (CT)-proven colonic diverticulitis were included. The primary outcome was the recurrence of diverticulitis, which was defined as another episode of occurrence of the infection after index hospital stay. Cumulative recurrence rates were calculated using the Kaplan-Meier method. Cox regression models were employed to identify parameters that significantly and independently predicted recurrence. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. A total of 929 patients were included. Diverticulitis in the cecum/ascending occurred in 675 (72.6%) patients. The average follow-up period was 651 days. Recurrence was observed in 115 (12.4%) patients and most significantly observed in patients with sigmoid diverticulitis (HR, 2.24; 95% CIs 1.59-3.97), followed by those with descending colon diverticulitis (HR, 1.92; 95% CIs 1.17-3.25). Although most of the Asian patients had right-sided colonic diverticulitis, those with sigmoid diverticulitis had the highest risk of recurrence.

Survival factors in patients of high fall - A 10-year level-I multi-trauma center study.

OBJECTIVES: This study aims to investigate the characteristics of patients after free falls at the Level-I trauma centers. The factors associated with survival were differentiated. METHODS: This retrospective study was conducted at the National Taiwan University Hospital, the Hsin-Chu branch, and the Yun-Lin branch, all accredited as Level-I trauma centers between January 2010 and September 2020. Adult patients with falls from height of more than one story (i.e. 3.6 m) were included. Clinical data were obtained from electronic medical records. Odds ratios (OR) were computed with 95% confidence intervals (CIs) for significant parameters for survival. RESULTS: A total of 371 patients were included. Only 2 survived to discharge with poor neurologic outcomes in 101 patients with OHCA. The overall mortality rate was 98% and 11% in patients with and without OHCA. A higher falling height with a one-meter increase (OR, 1.14, 95% CI, 1.10-1.19) was significantly related to OHCA, especially the height over 6 m (OR, 3.07, 95% CI, 1.19-7.94). A higher trauma injury severity score (TRISS) was significantly related to survival among patients without OHCA (OR, 1.07, 95% CI, 1.04-1.11), especially TRISS≧0.945 (OR, 5.21, 95% CI, 1.28-21.24). Patients without severe head/neck injury of Abbreviated Injury Scale (AIS)≧3 (OR, 0.17, 95% CI, 0.07-0.42) were positively associated with survivors among patients without OHCA. CONCLUSION: Patients with traumatic OHCA following falls had a high mortality rate of 98% and dismal outcomes, compared with non-traumatic OHCA. Falling heights, especially over 6 m was associated with OHCA. Patients without OHCA had a mortality rate of 11%. Patients with a higher TRISS, especially more than 0.945, or without severe head injury had more chances to survive in the non-OHCA group. The study provided the evidence to guide termination of high futility resuscitation for traumatic OHCA secondary to falls to conserve the clinical resources.

Installation of Pargyline, a LSD1 Inhibitor, in the HDAC Inhibitory Template Culminated in the Identification of a Tractable Antiprostate Cancer Agent.

Pragmatic insertion of pargyline, a LSD1 inhibitor, as a surface recognition part in the HDAC inhibitory pharmacophore was planned in pursuit of furnishing potent antiprostate cancer agents. Resultantly, compound 14 elicited magnificent cell growth inhibitory effects against the PC-3 and DU-145 cell lines and led to remarkable suppression of tumor growth in human prostate PC-3 and DU-145 xenograft nude mouse models. The outcome of the enzymatic assays ascertained that the substantial antiproliferative effects of compound 14 were mediated through HDAC6 isoform inhibition as well as selective MAO-A and LSD1 inhibition. Moreover, the signatory feature of LSD1 inhibition by 14 in the context of H3K4ME2 accumulation was clearly evident from the results of western blot analysis. Gratifyingly, hydroxamic acid 14 demonstrates good human hepatocytic stability and good oral bioavailability in rats and exhibits enough promise to emerge as a therapeutic for the treatment of prostate cancer in the near future.

Recent Update of HDAC Inhibitors in Lymphoma.

Modulating epigenetic modification has been recognized for over a decade as an effective therapeutic approach to cancer and many studies of histone deacetylase (HDAC), one of the best known epigenetic modulators, have been published. HDAC modulates cell proliferation and angiogenesis and plays an essential role in cell growth. Research shows that up-regulated HDACs are present in many cancer types and synthetic or natural HDAC inhibitors have been used to silence overregulated HDACs. Inhibiting HDACs may cause arrest of cell proliferation, angiogenesis reduction and cell apoptosis. Recent studies indicate that HDAC inhibitors can provide a therapeutic effect in various cancers, such as B-cell lymphoma, leukemia, multiple myeloma and some virus-associated cancers. Some evidence has demonstrated that HDAC inhibitors can increase the expression of immune-related molecules leading to accumulation of CD8 + T cells and causing unresponsive tumor cells to be recognized by the immune system, reducing tumor immunity. This may be a solution for the blockade of PD-1. Here, we review the emerging development of HDAC inhibitors in various cancer treatments and reduction of tumor immunity.

Unique Epigenetic Programming Distinguishes Regenerative Spermatogonial Stem Cells in the Developing Mouse Testis.

Spermatogonial stem cells (SSCs) both self-renew and give rise to progenitors that initiate spermatogenic differentiation in the mammalian testis. Questions remain regarding the extent to which the SSC and progenitor states are functionally distinct. Here we provide the first multiparametric integrative analysis of mammalian germ cell epigenomes comparable with that done for >100 somatic cell types by the ENCODE Project. Differentially expressed genes distinguishing SSC- and progenitor-enriched spermatogonia showed distinct histone modification patterns, particularly for H3K27ac and H3K27me3. Motif analysis predicted transcription factors that may regulate spermatogonial subtype-specific fate, and immunohistochemistry and gene-specific chromatin immunoprecipitation analyses confirmed subtype-specific differences in target gene binding of a subset of these factors. Taken together, these results show that SSCs and progenitors display distinct epigenetic profiling consistent with these spermatogonial subtypes being differentially programmed to either self-renew and maintain regenerative capacity as SSCs or lose regenerative capacity and initiate lineage commitment as progenitors.

Fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides as antitumor agents against CRC and NSCLC cancer cells.

A major cause of failure of therapy in patients with non-small cell lung cancer (NSCLC) is development of acquired drug resistance leading to tumor recurrence and disease progression. In addition to the development of new generations of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), different molecular targets may provide opportunities to improve the therapeutic outcomes. In this study, we utilized the core structure 5-fluorouracil (5-FU) or tegafur, a 5-FU prodrug combined through different linkers with resorcinol to generate a series of fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides which inhibit potent Heat Shock Protein 90 (HSP90). These compounds were found to show significant antiproliferative activity in colorectal cancer (CRC) HCT116 and NSCLC A549, H460, and H1975 (EGFR L858R/T790 M double mutation) cells. Compound 12c, developed by molecular docking analysis and enzymatic assays exhibits promising inhibitory activity of HSP90. This compound, 12c shows the most potent HSP90 inhibitory activity with an IC50 value of 27.8 ± 4.4 nM, superior to that of reference compounds AUY-922 (Luminespib) and BIIB021 whose IC50 values are 43.0 ± 0.9 nM and 56.8 ± 4.0 nM respectively. This strong HSP90 inhibitory activity of 12c leads to rapid degradation of client proteins EGFR and Akt in NSCLC cells. In addition, 12c induces significant accumulation of a sub-G1 phase population in parallel with apoptosis by showing activated caspase-3, -8 and -9 and PARP induction. These results provide a new strategy for development of novel HSP90 inhibitors for cancer treatment.

The Mammalian Spermatogenesis Single-Cell Transcriptome, from Spermatogonial Stem Cells to Spermatids.

Spermatogenesis is a complex and dynamic cellular differentiation process critical to male reproduction and sustained by spermatogonial stem cells (SSCs). Although patterns of gene expression have been described for aggregates of certain spermatogenic cell types, the full continuum of gene expression patterns underlying ongoing spermatogenesis in steady state was previously unclear. Here, we catalog single-cell transcriptomes for >62,000 individual spermatogenic cells from immature (postnatal day 6) and adult male mice and adult men. This allowed us to resolve SSC and progenitor spermatogonia, elucidate the full range of gene expression changes during male meiosis and spermiogenesis, and derive unique gene expression signatures for multiple mouse and human spermatogenic cell types and/or subtypes. These transcriptome datasets provide an information-rich resource for studies of SSCs, male meiosis, testicular cancer, male infertility, or contraceptive development, as well as a gene expression roadmap to be emulated in efforts to achieve spermatogenesis in vitro.

Pluripotent cells display enhanced resistance to mutagenesis.

Pluripotent cells have been reported to exhibit lower frequencies of point mutations and higher levels of DNA repair than differentiated cells. This predicts that pluripotent cells are less susceptible to mutagenic exposures than differentiated cells. To test this prediction, we used a lacI mutation-reporter transgene system to assess the frequency of point mutations in multiple lines of mouse pluripotent embryonic stem cells and induced pluripotent cells, as well as in multiple lines of differentiated fibroblast cells, before and after exposure to a moderate dose of the mutagen, methyl methanesulfonate. We also measured levels of key enzymes in the base excision repair (BER) pathway in each cell line before and after exposure to the mutagen. Our results confirm that pluripotent cells normally maintain lower frequencies of point mutations than differentiated cells, and show that differentiated cells exhibit a large increase in mutation frequency following a moderate mutagenic exposure, whereas pluripotent cells subjected to the same exposure show no increase in mutations. This result likely reflects the higher levels of BER proteins detectable in pluripotent cells prior to exposure and supports our thesis that maintenance of enhanced genetic integrity is a fundamental characteristic of pluripotent cells.

Dynamic Variations in Genetic Integrity Accompany Changes in Cell Fate.

Pluripotent stem cells hold the potential to form the basis of novel approaches to treatment of disease in vivo as well as to facilitate the generation of models for human disease, providing powerful avenues to discovery of novel diagnostic biomarkers and/or innovative drug regimens in vitro. However, this will require extensive maintenance, expansion, and manipulation of these cells in culture, which raises a concern regarding the extent to which genetic integrity will be preserved throughout these manipulations. We used a mutation reporter (lacI) transgene approach to conduct direct comparisons of mutation frequencies in cell populations that shared a common origin and genetic identity, but were induced to undergo transitions in cell fate between pluripotent and differentiated states, or vice versa. We confirm that pluripotent cells normally maintain enhanced genetic integrity relative to that in differentiated cells, and we extend this finding to show that dynamic transformations in the relative stringency at which genetic integrity is maintained are associated with transitions between pluripotent and differentiated cellular states. These results provide insight into basic biological distinctions between pluripotent and differentiated cell types that impact genetic integrity in a manner that is directly relevant to the potential clinical use of these cell types.

The biatrial substrate properties in different types of paroxysmal atrial fibrillation.

BACKGROUND: The biatrial substrate properties in patients with paroxysmal atrial fibrillation (AF) originating from the pulmonary veins (PVs) and superior vena cava (SVC) are not available. OBJECTIVE: The purpose of this study is to characterize the differences of biatrial substrate properties in patients with different types of AF. METHODS: A total of 36 patients with paroxysmal AF originating from the PV (PV-AF) and 9 patients with paroxysmal AF initiating from the SVC (SVC-AF) were included. Regional electrogram voltage, conduction velocity (CV), and spectral analysis to identify the AF nest were performed to characterize the biatrial, PVs, and SVC substrate. RESULTS: In the left atrial (LA) body, the bipolar voltage, total activation time, CV, and dominant frequency (DF) were similar between the PV-AF and SVC-AF. However, in the PV regions, the electrogram voltage, CV, and DF were decreased in the PV-AF. The proportions of AF nest in the LA body (72.2% vs. 22.2%, P = .008) and PV regions (100% vs. 22.2%, P <.001) were higher in PV-AF compared with SVC-AF, respectively. On the other hand, lower bipolar voltage, longer total activation time, and slower CV of RA body were recognized in the SVC-AF as compared with the PV-AF. In the SVC, lower bipolar voltage, slower CV, higher DF, and higher proportions of AF nest in SVC (16.7% vs. 66.7%, P = .002) were identified in SVC-AF. CONCLUSION: These most-remodeled substrates in different types of paroxysmal AF indicated the importance of the atrial substrate in the vicinity of the arrhythmogenic thoracic veins.

Efficacy and safety of valsartan in hypertensive Taiwanese patients: post-marketing surveillance study.

OBJECTIVE: To evaluate the efficacy and safety of valsartan in Taiwanese patients with essential hypertension. METHODS: This 12-week multi-center, open-label, observational, post-marketing surveillance study enrolled 2046 hypertensive patients who were prescribed valsartan 80 or 160 mg as monotherapy or in combination with other antihypertensives based on clinical judgment. The primary endpoint was the incidence rate of dizziness with valsartan 160 mg monotherapy or combination therapy at Week 4. Secondary endpoints included the blood-pressure-lowering efficacy and the overall safety and tolerability of valsartan at Weeks 4 and 12. RESULTS: The monotherapy and combination groups had comparable baseline characteristics. At Week 4, monotherapy was found non-inferior to combination for incidence rate of dizziness (monotherapy, 9.25%; combination, 10%; difference in incidence of dizziness, 0.75%; 95% CI - 0.61% to 2.12%; non-inferiority margin, -1.33%;WaldTest approach). Greater blood pressure (BP) reduction was noted atWeek 12 than atWeek 4.The antihypertensive effect was greater with combination therapy and the 160-mg dose. BP control (systolic <140 mmHg or diastolic <90 mmHg) was achieved in 80-90% patients.Valsartan was well tolerated; most commonly reported adverse events included dizziness, headache, constipation and cough. CONCLUSION: Valsartan is an effective treatment option for essential hypertension in Taiwanese patients.

Expression of recombinant Hirudin in transgenic mice milk driven by the goat beta-casein promoter.

Hirudin, isolated from the leech Hirudo medicinalis, inhibits thrombin directly and several expression systems have been used to produce recombinant Hirudin (rHirudin) for pharmaceutical purposes. A DNA fragment containing the Hirudin coding sequence and goat beta-casein secretion signal was chemically synthesized in this study. The synthetic DNA then was further constructed into a goat beta-casein expression vector for mouse transgenesis. Four lines of transgenic mice were successfully developed and one line showed a meaningful anti-thrombin activity of 40,000 anti-thrombin units (ATU)/mL in their milk. In this animal line, Hirudin mRNA was found in samples of uterus and kidney with insignificant anti-thrombin activity (

Infectious intracranial aneurysms caused by Granulicatella adiacens.

Infectious intracranial aneurysms (IIAs) are uncommon but severe complications of bacterial endocarditis. We report a case of IIA due to a rare nutritionally variant streptococcus, Granulicatella adiacens. The 31-year-old young patient, without any known risk for infective endocarditis had a silent clinical course until rupture of IIAs occurred. Despite antibiotic treatment and surgical clipping of IIAs, a second episode of more severe intracerebral hemorrhage occurred four months later. Mitral valvuloplasty was undertaken and there were no more brain insults in the following four years. Awareness of the possibility of hemorrhagic stroke as the initial presentation of Granulicatella adiacens endocarditis, and the possibility of high recurrence and bacteriological failure rate of Granulicatella adiacens infection may be helpful in early diagnosis and surgical decision, thus limiting future fatal complications.

Protein expression of lymphocytes in HLA-DR transgenic pigs by a proteomic approach.

Matching donor and recipient human leucocyte antigen (HLA-II) could conquer cell-mediated rejection following transplantation. Transgenic pigs carrying HLA genes that "humanize" porcine organs, tissues, and cells were successfully generated. This study further clarifies the effect of HLA-DR transgenes on lymphocyte protein expression, via a proteomic approach. Lymphocytes were isolated from two HLA-DR transgenic pigs and three nontransgenic littermates on 157 d after birth. Soluble protein of 1x10(7) cells was separated using 2-DE. In total, 301 colloidal CBB-stained protein spots detected on all five 2-D gels were quantified. Thirty-three proteins were differentially expressed by a factor of 1.5. These proteins were subsequently identified by MALDI-TOF MS and MALDI-TOF/TOF MS/MS. These proteins were sorted into the following categories: chaperones, T-lymphocyte function, DNA/RNA processing, cytoskeleton-associated proteins, signal transduction, enzymes, and unknown. Previous studies have suggested that some of the identified proteins are associated with lymphocyte activation/proliferation. The identities of the unidentified spots and the systematic effect of these up- and down-regulated proteins on T-cell function in HLA-DR transgenic pigs require further exploration.

Aortic smooth muscle relaxants KMUP-3 and KMUP-4, two nitrophenylpiperazine derivatives of xanthine, display cGMP-enhancing activity: roles of endothelium, phosphodiesterase, and K+ channel.

The cellular mechanisms of vasorelaxant effects of newly synthesized KMUP-3 and KMUP-4 were investigated in rat aortic smooth muscle (RASM). KMUP-3 (7-[2-[4-(4-nitrobenzene)piperazinyl]ethyl]-1,3-dimethylxanthine) and KMUP-4 (7-[2-[4-(2-nitrobenzene)piperazinyl]ethyl]-1,3-dimethylxanthine) elicited concentration-dependent relaxation of endothelium-intact and denuded RASM precontracted with phenylephrine. Relaxant responses were also produced by the PDE inhibitors theophylline, milrinone, rolipram, and zaprinast (1 nM-100 microM). The relaxant responses of KMUP-3 and KMUP-4 were reduced by endothelium removal and by the presence of the NOS inhibitor L-NAME (100 microM), the sGC inhibitor ODQ (1 microM), the adenylyl cyclase (AC) inhibitor SQ 22536 (100 microM), and the prostaglandin inhibitor indomethacin (10 microM). Additionally, the vasorelaxations of both agents were also attenuated by pretreatment with the nonselective K+ channel blocker TEA (10 mM), the KATP channel blocker glibenclamide (1 microM), the voltage-dependent K+ (KV) channel blocker 4-AP (100 microM), and Ca(2+)-dependent K+ (KCa) channel blockers apamin (1 microM) and charybdotoxin (ChTX, 0.1 microM). In addition, elevated extracellular K+ (80 mM) interferes with KMUP-3- and KMUP-4-induced vasorelaxations. Preincubation with both agents (1 microM) significantly enhanced the dilator responses of isoproterenol and SNP. KMUP-3 and KMUP-4 inhibited PDE activities and increased cAMP and cGMP levels in primary culture of RASM that were inhibited by SQ 22536 and ODQ, respectively. In cultured HUVECs, KMUP-3 and KMUP-4 (0.1 microM), more potent than YC-1, significantly increased the expression of eNOS protein. In summary, KMUP-3 and KMUP-4 induce aortic relaxations through both endothelium-dependent and -independent mechanisms. Mechanisms of vasorelaxation induced by both compounds involve multiple processes, such as accumulation of cyclic nucleotides partly as a result of PDE inhibition, K-channel activation, and indomethacin-sensitive endothelium function.