[Progress in application of aspirin desensitization and maintenance therapy in aspirin-exacerbated respiratory disease]

Aspirin-exacerbated respiratory disease (AERD) is a clinical syndrome characterized by chronic rhinosinusitis with nasal polyps, asthma and the development of significant airway symptoms following the ingestion of aspirin and other nonsteroid anti-inflammatory drugs (NSAIDs). At present, aspirin challenge is the gold standard for diagnosis. Aspirin desensitization and aspirin therapy after desensitization (ATAD) is one of the classical therapies. This paper described the application of aspirin desensitization and ATAD in AERD and provided the reference for the comprehensive treatment of AERD.

Comparing the effectiveness of bivalent and monovalent COVID-19 vaccines against COVID-19 infection during the winter season of 2022-2023: A real-world retrospective observational matched cohort study in the Republic of Korea

OBJECTIVES

To compare the effectiveness of bivalent and monovalent COVID-19 vaccines throughout the 2022-2023 winter season based on real-world data.

METHODS

This retrospective observational matched cohort study used the national vaccination program and a surveillance dataset from the Republic of Korea, and included adults aged >18 years who received bivalent or monovalent COVID-19 vaccines between October 11, 2022, and December 17, 2022. Cox proportional hazard models were used to estimate the hazard ratio for COVID-19 infection between the groups.

RESULTS

We included 29,245 matched individuals in the bivalent and monovalent vaccine groups, respectively. The bivalent vaccine recipients showed 12.2% (95% confidence interval [CI] 6.5-17.7%) additional protection against COVID-19 infection compared with the monovalent vaccine recipients. The additional protection provided by bivalent vaccines was significantly higher among residents of long-term care facilities (39.4%, 95% CI 21.6-53.1%). Maximum additional protection was observed 3 to 4 months after completing the vaccination (17.6%, 95% CI 6.6-27.3%).

CONCLUSION

Bivalent COVID-19 vaccines showed significantly better protection against infection than monovalent vaccines among adults during the 2022-2023 winter season. Our results highlight that immunization programs with bivalent vaccines comprising recent variants can be an effective measure to prepare for seasonal COVID-19 circulation.

[Clinical observation and preliminary economic study of rush immunotherapy in patients with allergic rhinitis]

Objective: To observe the clinical efficacy, safety, compliance, and cost-effectiveness of rush immunotherapy (RIT) and conventional immunotherapy (CIT) in patients with allergic rhinitis (AR), so as to evaluate the clinical significance of CIT and preliminarily explore its economic value. Methods: A study was conducted on 72 AR patients who had received specific immunotherapy from Oct 2019 to Jun 2020 in the Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University, including 39 males and 33 females, aging 8 to 60 years. RIT or CIT was performed respectively according to the patients' wishes. There were 35 cases in the RIT group and 37 cases in the CIT group, all subjects were followed up for 1 year. Visual analysis scale (VAS) and effectiveness were used to evaluate the clinical efficacy. Systemic adverse reactions were used to assess safety. Failure rate was calculated to evaluate the compliance. The cost and cost-effectiveness ratio (CER) were conducted to evaluate the health economics preliminarily. Results: After half a year and one year's treatment, both RIT and CIT groups had significant clinical efficacy and RIT group had more significant clinical efficacy than CIT group at half a year (76.67% vs 46.67%, χ²=7.37, P=0.007). During the dose accumulation phase, there was no significant difference in the incidence of systemic adverse reactions between the two groups (8.57% vs 8.10%, χ²=0.05, P=0.943), while the drop-out rate in the RIT group was significantly lower than that in the CIT group (0 vs 13.51%, χ²=5.08, P=0.024). After one year, the costs in RIT group were significantly higher ((8 163.08±452.67) yuan vs (7 385.87±369.92) yuan, t=-2.78, P=0.009), while there was no statistical differences in CER between the two groups ((3 298.06±1 374.09) yuan/point vs (3 154.38±1 532.51) yuan/point, t=-0.36, P=0.418). Conclusions: Both RIT and CIT are beneficial for AR, and they have similar clinical efficacy, safety, and CER. RIT is more effective in the early stage, with higher patient compliance. Thus, RIT is worth promoting and exploring in clinic.

[Application of the subjective and objective evaluation in functional rhinoplasty]

Objective: To explore the subjective and objective evaluation methods in functional rhinoplasty. Methods: Sixty-four patients who underwent rhinoplasty in the Department of Otorhinolaryngology, the First Affiliated Hospital of Chongqing Medical University were included in this study from January 2017 to October 2018. There were 32 males and 32 females, with the age ranging from 18 to 45 years old. Before and 6 months after operation, nasal ventilation function was evaluated by Visual Analogue Scale (VAS), Nasal Obstruction Symptom Evaluation (NOSE), nasal acoustic reflex and nasal resistance. Satisfaction with nasal appearance was evaluated by VAS, Rhinoplasty Outcome Evaluation (ROE) and facial proportions evaluation. Psychological state was assessed by Emotional Balance Scale and Rosenberg Self-esteem Scale. Finally, the Pearson correlation analysis of patient satisfaction was performed. SPSS 23.0 software was used for statistical analysis. Results: Compared with pre-operation, nasal obstruction VAS, NOSE scores, total nasal resistance and difference ratio of nasal resistance showed significantly decline after surgery (1.62±0.85 vs 7.56±1.44, 22.62±3.54 vs 69.75±7.85, (0.16±0.08) Pa·s/ml vs (0.31±0.43) Pa·s/ml, 0.33±0.28 vs 0.71±0.32, all P<0.05). VAS of appearance and ROE scores showed an increase after surgery (11.20±3.66 vs 2.70±0.97, 17.80±2.71 vs 7.50±1.12, all P<0.05). The measurement of the external nasal subunits showed that the length of the dorsum of the nose, the angle of the face to the nose, the angle of the frontal and the angle of the alar of the nose were obviously reduced ((29.33±4.26) mm vs (33.61±5.24) mm, (135.11±3.81)° vs (139.91±6.30)°, (130.63±2.88)° vs (136.74±5.72)°, (99.71±4.02)° vs (106.27±5.60)°, all P<0.05). The scores of postoperative Emotional Balance Scale and Rosenberg Self-esteem Scale increased significantly (5.88±1.54 vs 4.31±1.85, 28.31±2.64 vs 22.13±2.77, all P<0.05). The Pearson correlation analysis showed that patients' satisfaction was positively correlated with subjective score of nasal ventilation (VAS, NOSE), subjective score of nasal appearance (VAS, ROE) and emotional balance scale, while negatively correlated with nasal resistance, and not correlated with the measurement of external nasal subunit. There was a significant positive correlation between the subjective score of nasal ventilation and the measurement of nasal resistance, but there was no significant correlation between the subjective score of nasal appearance and the measurement of external nasal subunit. Conclusion: The subjective and objective evaluation of nasal ventilation function, aesthetics of nasal appearance and psychological state can evaluate the effect of functional rhinoplasty effectively.

[Situation analysis of timing of first visit of anti-mitochondrial antibody-positive patients]

Objective: To understand the basic information of anti-mitochondrial antibody (anti-AMA)-positive patients after initial diagnosis, and to set groundwork for further exploring the clinical significance of AMA in various diseases. Methods: Demographic data and related clinical information recorded through the Information System of Peking University People's Hospital from January 2013 to December 2016 were collected. Patients whose AMA and/or AMA-M2 first- tested as positive were recorded. Complications were classified according to the International Classification of Diseases. Results: A total of 1323 AMA positive cases were discovered for the first time. Among them, 78.0% were women, and the age of initial diagnosis was 56.8 ± 16.0 years. The first three initially diagnosed departments were rheumatology and immunology (37.4%), liver Disease (15.9%) and hematology (15.9%) relevant to musculoskeletal and connective tissue diseases (45.2%), hematology and hematopoietic organs and immune diseases (30.6%) and circulatory system diseases (29.7%). There were 297 newly confirmed cases of primary biliary cholangitis (PBC); accounting for 89.2% of women, and the age of initial diagnosis was 60.1 ± 12.4 years. The top three departments of initially diagnosed as PBC were liver disease (37.7%), rheumatology (33.0%) and gastroenterology (15.2%), of which 39.7% had musculoskeletal and connective tissue diseases, 27.9% had circulatory diseases, and 24.9 % were combined with endocrine and metabolic diseases. Conclusion: Besides PBC and other autoimmune diseases, AMA and / or AMA-M2 positivity can be observed in a variety of diseases in several clinical departments, and its clinical significance remains to be further clarified.

[Rosai-Dorfman disease with nasal septum involvement:two cases report]

Clinical data of 2 cases with Rosai-Dorfman disease(RDD) originating from nasal septal mucosa were reported retrospectively,and the pertinent literature was reviewed. Without specific clinical features,RDD in nasal cavity could be misdiagnosed easily. Pathology revealed different morphologies of cell proliferation with engulfed lymphocytes,plasma cells and neutrophils. Immunohistochemical staining showed S-100(+),CD68(+)，CD1(-).RDD disease generally has a benign course and is self-limited. Its diagnosis depends mainly on biopsy．As for the treatment of this disease,the strategies are not systemic and standard. Surgical treatment is used to excise the mass in nasal cavity,glucocorticoids treatment after surgery is inconclusive. The long-term effect need to be further observed．.

[The guiding role of preoperative visual analog scale symptom scores in patients with chronic rhinosinusitis during perioperative period]

Objective:To assess the guiding role of preoperative visual analog scale(VAS) symptom scores in patients with chronic rhinosinusitis(CRS) during perioperative period.Method:The patients with CRS undergoing endoscopic sinus surgery were divided into experimental group and control group according to doctor group.Preoperative VAS symptom scores which including the overall symptom score and every single symptom scores were assessed. Patients with symptom(nasal congestion, nasal discharge, dizziness or headache, hypoamia or anosmia, rhinocnesmus, sneeze) scores more than 5 points were taken corresponding appropriate strategies in experimental group, but conventional empirical measures in control group during perioperative period.Nasal endoscopic surgeries were performed under local or general anesthesia after preoperative preparation. Postoperative followup were performed in six months and one year for the overall symptom and each symptom scores in both groups. SPSS17.0 was used for statistical analysis.Result:There was no statistical difference in general condition, overall symptom score and every symptom scores before operation between experimental group(120 cases) and control group(82 cases) (P >0.05). At the three time points (preoperative, six months, one year after operation), significant differences were found in the two groups about VAS overall symptom score (P <0.05). Except hypoamia, VAS for the other symptoms in different postoperative time showed statistical significance (P <0.05).Conclusion:Preoperative VAS symptom score can be used not only in the evaluation of severity and treatment effect,but also in the guiding of perioperative treatment for CRS, which is worthy of using widely in clinic.

[Association between IL-27 gene polymorphisms and susceptibility to allergic rhinitis]

Objective: To evaluate the potential association of IL-27 polymorphisms with allergic rhinitis(AR) in a Chinese Han population. Method:A case-control study was performed in 445 Chinese AR patients and 691 healthy controls. Three SNPs in the IL-27p28 gene, including rs153109, rs17855750 and rs181206, were detected using a polymerase chain reaction-restriction fragment length polymorphism assay(PCR-RFLP). Result:A significantly increased prevalence of the rs153109 TT genotype and the T allele was found in AR patients, while a decreased prevalence of the CT and CC genotypes and the C allele was found. For rs153109, the TT genotype and the T allele were significantly associated with the risk of AR, but the CT and CC genotypes and the C allele decreased the risk of AR; for rs17855750, the TT genotype and T allele were risk factors for AR, and the GT genotype and G allele provided protection. TTT and TTC haplotypes in the IL-27 p28 gene were positively correlated with AR, while CGT, CTC and CTT haplotypes were associated with a significantly decreased risk of AR. Conclusion:This study indicates that IL-27 p28 polymorphisms rs153109 and rs17855750 are likely involved in AR susceptibility, making them potentially useful genetic biomarkers for AR susceptibility in the Chinese Han population.

Magnitude and Structure of Isometric Force Variability: Mechanical and Neurophysiological Influences

This experiment examined the magnitude and structure of force variability in isometric index finger force production tasks at 5, 15, 25, 35, 45, 55, 65, 75, 85, and 95% of maximal force in two different finger orientations. In the finger flexion task, the participants generated a downward isometric force through index finger flexion. In the finger abduction task, isometric force was generated by adducting the index finger (mediolateral motion of the middle finger and forearm were restricted). The task-related, normal force (Fz) and tangential forces (Fx and Fy) were collected with a three-dimensional force transducer. The standard deviation (SD) of the task-related force output (Fz) increased exponentially with force level. With increasing force level, approximate entropy (ApEn, a measure of irregularity) of Fz followed an inverted-U function for finger flexion, but decreased linearly in finger abduction. However, changes in the ApEn of the tangential forces were generally opposite to that of Fz, revealing compensations in the irregularity of force output between force dimensions. The findings provide evidence that force variability is related to muscle force-length characteristics (Feldman, 1966; Gottlieb %%% Agarwal, 1988).

Inverse relations in the patterns of muscle and center of pressure dynamics during standing still and movement postures

The aim of this study was to investigate the postural center of pressure (COP) and surface muscle (EMG) dynamics of young adult participants under conditions where they were required to voluntarily produce random and regular sway motions in contrast to that of standing still. Frequency, amplitude and regularity measures of the COP excursion and EMG activity were assessed, as were measures of the coupling relations between the COP and EMG outputs. The results demonstrated that, even when standing still, there was a high degree of regularity in the COP output, with little difference in the modal frequency dynamics between standing still and preferred motion. Only during random conditions was a significantly greater degree of irregularity observed in the COP measures. The random-like movements were also characterized by a decrease in the level of synchrony between COP motion on the anterior-posterior (AP) and medio-lateral (ML) axes. In contrast, at muscle level, the random task resulted in the highest level of regularity (decreased ApEn) for the EMG output for soleus and tibialis anterior. The ability of individuals to produce a random motion was achieved through the decoupling of the COP motion in each dimension. This decoupling strategy was reflected by increased regularity of the EMG output as opposed to any significant change in the synchrony in the firing patterns of the muscles examined. Increased regularity across the individual muscles was accompanied by increased irregularity in COP dynamics, which can be characterized as a complexity tradeoff. Collectively, these findings support the view that the dynamics of muscle firing patterns does not necessarily map directly to the dynamics at the movement task level and vice versa.

Test-retest reliability and criterion validity of the Chinese version of CBCL, TRF, and YSR

BACKGROUND

Psychometric properties of the Chinese version of CBCL, TRF, and YSR were understudied. This study aimed at examining their test-retest reliability and criterion validity.

METHODS

Three Chinese community and clinic samples were recruited in Hong Kong. The parents, teachers, and youths respectively completed the CBCL, TRF, and YSR.

RESULTS

The Chinese CBCL, TRF, and YSR were test-retest reliable and valid. However, there was score/case attenuation at retest. CBCL and TRF appeared to screen externalizing and ADHD problems better, while YSR screened internalizing problems better.

CONCLUSIONS

Clinicians should be cautious about score/case attenuation at retest while using CBCL, TRF, and YSR to chart patients' progress. They should also recognize their different strengths in screening various disorders.

Change in the Organization of Degrees of Freedom With Learning

The authors examined the effects of learning on the change in the organization of the mechanical and dynamical degrees of freedom in 5 men who performed a ski-simulator task. A 3-dimensional analysis of the motion of the total-body center of mass and the segmental centers of mass (head, torso, thighs, and shanks) over practice showed that the recruitment of mechanical degrees of freedom was strongly influenced by anatomical and task constraints. Principal components analysis of the body segments' motions revealed that practice shifted their relative contributions but did not change the number of principal components. The present findings show that there can be independence in the patterns of change in the mechanical and dynamical degrees of freedom that arise from practice.

Practice effects on local and global dynamics of the ski-simulator task

This experiment examined the acquisition of the global and local dynamics of the changes in the total body center of mass-platform and inter-limb coordination motions over the course of practice (20, 30 s trials each day for 7 days) in the ski-simulator task. Four blocks of trials, representative of early, moderate, and extensive practice were analyzed through power spectrum and coherence analyses. The oscillation frequencies of the knee joints became tuned to that of the platform-performer system and there were changes due to practice in the lower inter-limb coordination dynamics independent of the center of mass and platform coordination pattern. Acquisition of global level dynamics occurs to achieve a stable task solution that can allow for degenerate frequency- and phase-locking of the mechanical degrees of freedom at both the local intra- and inter-limb levels.

Multimerization potential of the cytoplasmic domain of the human immunodeficiency virus type 1 transmembrane glycoprotein gp41

We previously demonstrated that an envelope mutant of human immunodeficiency virus type 1 lacking the entire cytoplasmic domain interferes in trans with the production of infectious virus by inclusion of the mutant envelope into the wild-type envelope complex. We also showed that the envelope incorporation into virions is not affected when the wild-type envelope is coexpressed with the mutant envelope. These results suggest that an oligomeric structure of the cytoplasmic domain is functionally required for viral infectivity. To understand whether the cytoplasmic domain of human immunodeficiency virus type 1 transmembrane protein gp41 has the potential to self-assemble as an oligomer, in the present study we fused the coding sequence of the entire cytoplasmic domain at 3' to the Escherichia coli malE gene, which encodes a monomeric maltose-binding protein. The expressed fusion protein was examined by chemical cross-linking, sucrose gradient centrifugation, and gel filtration. The results showed that the cytoplasmic domain of gp41 assembles into a high-ordered structural complex. The intersubunit interaction of the cytoplasmic domain was also confirmed by a mammalian two-hybrid system that detects protein-protein interactions in eucaryotic cells. A cytoplasmic domain fragment expressed in eucaryotic cells was pulled down by glutathione-Sepharose 4B beads via its association with another cytoplasmic domain fragment fused to the C terminus of the glutathione S-transferase moiety. We also found that sequences encompassing the lentiviral lytic peptide-1 and lentiviral lytic peptide-2, which are located within residues 828-856 and 770-795, respectively, play a critical role in cytoplasmic domain self-assembly. Taken together, the results from the present study indicate that the cytoplasmic domain of gp41 by itself is sufficient to assemble into a multimeric structure. This finding supports the hypothesis that a multimeric form of the gp41 cytoplasmic domain plays a crucial role in virus infectivity.

Characterization of cytosolic phospholipases C from porcine aortic endothelial cells

Phospholipases C (PLCs) are ubiquitous enzymes which play key roles in the response of cells to extracellular agonists. Endothelial cells are involved in myriad normal and pathophysiologic functions. Although it is known that agonists activate PLCs in endothelial cells, second messengers form, and cellular responses ensue, more knowledge is needed about the specific types of PLCs in these cells. To this end, cytosolic PLCs from porcine aortic endothelial cells were partially purified by ammonium sulfate fractionation and column chromatography on DEAE-Sepharose CL-6B and heparin-agarose. Three PLC isozymes immunologically similar to bovine brain PLC-beta, PLC-gamma, and PLC-delta were identified. The relative levels of PLC activities in the cytosol were: PLC-beta, 50%; PLC-gamma, 44%; PLC-delta, 6%. The level of PLC-beta activity in porcine endothelial cells appeared higher than the levels reported for several established cell lines, suggesting that this enzyme may play a specific role in endothelial cell function. Elution profiles of PLC activity with phosphatidylinositol 4,5-bisphosphate (Ptdlns(4,5)P2) as substrate were similar to those with phosphatidylinositol (Ptdlns) as substrate, indicating that cytosolic PLCs hydrolyze both Ptdlns and Ptdlns(4,5)P2 and no Ptdlns(4,5)P2-specific PLC was present in the cytosol. The catalytic properties of the partially purified PLC isozymes from porcine endothelial cells were similar to their counterparts from bovine brain. These include the dependence of hydrolysis of Ptdlns on Ca2+, the optimal Ca2+ concentrations for the hydrolysis of Ptdlns and Ptdlns(4,5)P2, the pH optima, and the stimulatory effects of deoxycholate.

Glycoconjugate mediated endothelial cell adhesion to Dacron polyester film

PURPOSE

The purpose of this study was to explore new strategies for enhancing specific cell type attachment to biomaterials using immobilized lectins for cell surface glycoconjugates. The lectin Ulex europaeus I (UEA I) has a high affinity for human vascular endothelial cell surface glycoconjugates.

METHODS

UEA I was covalently bound to polyethylene terephthalate (Dacron) with the cross-linking agent 1-ethyl-3-(dimethylaminopropyl)carbodiimide hydrochloride to achieve oligosaccharide-mediated endothelial cell attachment to this otherwise nonadherent surface.

RESULTS

Experiments with radiolabeled UEA I demonstrated covalent linkage of as much as 1.35 micrograms/cm2. The lectin binding site is available after the reaction, as demonstrated in experiments a neoglycoprotein. Adhesion studies reveal a 100-fold increase in endothelial cell attachment for the UEA I/polyethylene terephthalate surface (99.7 +/- 29.6 cells/high-power field) when compared with untreated (0.7 +/- 0.5), crosslinking agent (0.4 +/- 0.3), and denatured UEA I (1.2 +/- 1.1) control groups. Five vascular endothelial cell lines adhered to the UEA I/polyethylene terephthalate surface, whereas monocytes, smooth muscle cells, and fibroblasts did not.

CONCLUSION

These results imply new strategies for endothelialization of prosthetic grafts and promotion of selective cell adherence to biomaterials, with emphasis on carbohydrate interactions. Moreover, this experimental system offers a model for exploring the biologic significance of the endothelial cell-UEA I ligand.

[Studies on the structure of alpha-trans-bergamotenol from Chinese santalwood oil]

A new sesquiterpenol was isolated from santalwood oil (Santalum album L., Santalaceae). Its structure and relative stereochemistry were elucidated on the basis of spectral analysis (IR, MS, 1H-1H COSY, 13C-1H COSY and 1H-1H NOESY) as 9(10)Z, alpha-trans-bergamotenol (Ia).

[Effect of bradykinin, ionophore A23187 and trypsin on prostacyclin release from calf and pig aorta endothelial cells]

This paper details the methods of establishing stock culture and subculture of calf and pig aorta endothelial cells and the effects of bradykinin, ionophore A23187, trypsin and arachidonic acid (AA) on the release of prostacyclin (PGI2) from the cells. The release was measured by 6-keto PGF1 alpha radioimmunoassay. The results showed that the stimuli significantly increased the release of PGI2 in the two endothelial cell types (P < 0.01, n = 8), and the release was much stronger in pig than in calf endothelial cells under the experimental conditions. We therefore suggest that the reactivities of the two endothelial cells to the stimuli differ. The results offer useful information for further research of the mechanism of their pharmacologic actions on endothelial cells and their relationship with PGI2.

Nasal mucosa sensitization with toluene diisocyanate (TDI) increases preprotachykinin A (PPTA) and preproCGRP mRNAs in guinea pig trigeminal ganglion neurons

Toluene diisocyanate (TDI) induces respiratory allergy in mammals. Using immunohistochemistry and in situ hybridization histochemistry, the present study examined effects of nasal mucosa sensitization by TDI on the immunoreactivity for substance P (SP) and calcitonin gene-related peptide (CGRP) and on the expression of their mRNAs in guinea pig trigeminal ganglion and their terminals. Single intranasal application of TDI (acute experiment) did not induce nasal allergy-like behaviours and failed to cause changes of SP and CGRP immunoreactivity and in the expression of preprotachykinin A (PPTA) mRNA and preproCGRP mRNA coding for SP and CGRP respectively in the trigeminal ganglion neurons. However, repeated application of TDI (chronic experiment) caused a dramatic increase of SP and CGRP immunoreactivity in peripheral neurites of sensory nerves in the nasal mucosa but a slight increase in the spinal trigeminal nucleus, a decrease of the same immunoreactivities in the cell bodies of the trigeminal ganglion neurons, and an increase of the expression of PPTA and preproCGRP mRNA in the same neurons. These findings suggest that chronic exposure of the nasal mucosa to TDI apparently causes enhancement of both the biosynthesis of SP and CGRP and their axonal transport in the trigeminal system.

Bradykinin-induced activation of phospholipase A2 is independent of the activation of polyphosphoinositide-hydrolyzing phospholipase C

This study evaluates the role of phosphatidylinositol 4,5-bisphosphate (PIP2) and its metabolites as possible mediators in the activation of phospholipases A2 in porcine aortic endothelial cells. We compared the time courses of bradykinin-induced turnover of phosphoinositides and the appearance of unesterified arachidonic acid (uAA) and eicosanoids. The metabolism of phosphoinositides was examined in cells prelabeled with [3H]inositol, which has a similar distribution as the endogenous inositol lipids. At 37 degrees C, bradykinin induced a rapid rise in lysophosphatidylinositol (lyso-PI) and inositol 1,4,5-trisphosphate (IP3) as well as a decrease in PIP2. Lyso-PI formation was detected at 10 s, as early as PIP2 degradation and IP3 formation. This suggests that the activation of PIP2-hydrolyzing phospholipase C and PI-hydrolyzing phospholipase A2 are simultaneous. However, at 30 degrees C, lyso-PI formation was detected in the absence of an increase in IP3 indicating that the activation of phospholipase A2 does not require the accumulation of IP3. The time course of formation of uAA and eicosanoids were examined in [3H]arachidonic acid-prelabeled cells. The 3H radioactivity was distributed among the phospholipid classes and subclasses the same as the endogenous phospholipids. Bradykinin stimulated the intracellular accumulation of uAA, detectable at 5 s, earlier than that of 1,2-diacylglycerol and phosphatidic acid. Such immediate formation of uAA further supports the notion that activation of phospholipase A2 is a very early event during the interaction of bradykinin with porcine endothelial cells, and that PIP2 hydrolysis is not prerequisite for the initial activation of phospholipase A2.

von Willebrand factor abnormalities and endothelial cell perturbation in a patient with acute thrombotic thrombocytopenic purpura

The plasma of a 63-year-old patient with an initial acute, fatal episode of thrombotic thrombocytopenic purpura (TTP) contained agglutinated platelets and a factor VIII-related von Willebrand factor (vWF) antigen level that was elevated seven-fold above normal. Unusually large vWF multimers derived from endothelial cells were detected in her plasma at the onset of the TTP episode. This is the first patient in whom vWF abnormalities indicative of in vivo endothelial cell damage or perturbation have been found during an acute episode of TTP.

Therapy of chronic relapsing thrombotic thrombocytopenic purpura with prednisone and azathioprine

As a 51-year-old woman recovered from an initial acute episode of thrombotic thrombocytopenic purpura (TTP), her plasma was found to contain unusually large von Willebrand factor (vWF) multimers. Clinical, hematological, and vWF studies of her siblings and children were normal. The unusually large vWF forms were presumably derived from endothelial cells, persisted in her plasma after recovery, and were associated with recurrent episodes of TTP during the subsequent 6 months. After the last episode of relapse they disappeared from her plasma following 3 1/2 weeks of therapy with prednisone and did not return during 17 months of treatment with prednisone and/or azathioprine. She is now receiving no drugs, has normal plasma vWF forms, and has not had any more episodes of TTP. We conclude that our patient had an acquired defect in the conversion of unusually large vWF multimers derived from endothelial cells to the somewhat smaller vWF forms usually present in circulation. The defect may have been immune-mediated, because it was eliminated during therapy with immunosuppressive drugs.

Genetics of ergoline alkaloid formation in Penicillium roquefortii

Auxotrophic, spore color, and alkaloid biosynthetic mutants of Penicillium roquefortii were selected after N-methyl-N'-nitro-N-nitrosoguanidine treatment. Diploids were obtained via protoplast fusion techniques, and the segregants from a diploid were genetically analyzed. The data demonstrated the potential of parasexual recombination in this organism. Evidence was obtained which suggests that the his and sts (sensitivity to Sulfatase) genes may be linked. The genetic information obtained in this study can serve as a starting point for further mapping of genes in P. roquefortii, and indications are that this organism may serve as a promising vehicle for the genetic study of the formation of ergoline alkaloids.

Effects of fresh-frozen plasma and its cryosupernatant fraction on von Willebrand factor multimeric forms in chronic relapsing thrombotic thrombocytopenic purpura

Remission plasma samples of some patients with chronic relapsing thrombotic thrombocytopenic purpura (TTP) contain unusually large von Willebrand factor (vWF) multimers similar to those produced by normal human endothelial cells in culture. The infusion of the cryosupernatant fraction of normal plasma is as effective as normal fresh-frozen plasma (FFP) in the treatment or prevention of TTP episodes in patients with the chronic relapsing form of TTP. Three patients with chronic relapsing TTP during remission have unusually large vWF multimers present in their plasma. Two of the patients were transfused once with FFP, one of the two received cryosupernatant on three occasions, and the third patient was studied before and immediately after plasma exchange. Unusually large vWF multimers decreased or disappeared from patient plasma samples within 1/2 to 1 1/2 hours following the transfusion of FFP (on two occasions) or cryosupernatant (on two of three occasions), and immediately after plasma exchange (on one occasion). The patient who received cryosupernatant was studied serially after the infusions. Unusually large vWF multimers returned to her plasma within ten to 24 hours and persisted thereafter. Unusually large vWF multimers did not disappear from patient remission plasma samples, or from the culture medium removed from normal human endothelial cells, when these fluids were incubated in vitro with either normal FFP or cryosupernatant. We conclude that an activity in FFP, and its cryosupernatant fraction, promoted the rapid in vivo disappearance of unusually large vWF multimers from the plasma of two patients with chronic relapsing TTP in remission, and plasma exchange reversed the abnormality in a third patient who was in partial remission. Neither FFP nor cryosupernatant directly converted unusually large multimers to smaller vWF forms in vitro in the fluid phase. These results indicate that an activity in the cryosupernatant fraction of normal plasma is involved in vivo in controlling the metabolism of unusually large vWF multimers, and that this process is defective in some chronic relapsing TTP patients.

Prostacyclin synthesis and deacylation of phospholipids in human endothelial cells: comparison of thrombin, histamine and ionophore A23187

Thrombin, histamine and ionophore A23187 stimulated human endothelial cells to release arachidonic acid and synthesize prostaglandins. To compare the activation of arachidonic acid release by these three stimuli in endothelial cells, we examined the intracellular lipid metabolism by prelabeling the cells with [14C]stearic acid and [3H]arachidonic acid. Thrombin stimulated the loss of 3H and 14C label from intracellular phospholipids. At the same time [3H]arachidonic acid and prostaglandins were released into the incubation medium. Thin layer chromatography analysis indicated that prostacyclin is the major metabolite formed followed by PGF2 alpha, PGE2, HHT and PGD2. In addition, several intracellular lipid metabolites were accumulated. These include: phosphatidic acid and 1,2-diacylglycerol detected by increase of both 14C and 3H radioactivity; lysophosphatidylinositol, lysophosphatidylethanolamine, and to a smaller extent lysophosphatidylcholine and lysophosphatidylserine detected by increase of 14C radioactivity. Like thrombin, both histamine and ionophore A23187 also stimulated release of arachidonic acid and synthesis of prostaglandins. Despite the different nature of the agonists, the type and the relative amount of prostaglandins synthesized in response to histamine and A23187 were similar to that stimulated by thrombin. The relative extents of hydrolysis of phospholipids and the accumulation of phosphatidic acid, 1,2-diacylglycerol and lysophospholipids are similar to that of 3H radioactivity and prostacyclin released into the medium and follow the order: ionophore A23187 greater than thrombin greater than histamine. These results suggest that in human endothelial cells, histamine, thrombin and ionophore A23187 directly or indirectly activated both phospholipase C and phospholipase A2 and these activations most likely involve mobilization of Ca2+.

Luminal release of prostacyclin and thromboxane A2 by arteries distal to small-caliber prosthetic grafts

Myointimal hyperplasia distal to prosthetic grafts may be due to a local imbalance of prostacyclin and thromboxane A2 that exaggerates platelet adherence. This study evaluated prostacyclin and thromboxane A2 production by arteries distal to prosthetic grafts. In 12 dogs, control segments of both iliac arteries were excised and a 5 cm segment of polytetrafluoroethylene was grafted end to end. One iliac artery was circumferentially dissected from the distal anastomosis to the inguinal ligament. The contralateral artery was not dissected. Of the 24 grafts, 19 remained patent and the arteries distal to these grafts were studied. After excision, each artery was analyzed for its ability to produce prostacyclin and thromboxane A2. Our data indicate that the luminal surface of a normal artery spontaneously produces both prostacyclin and thromboxane A2 and that the arterial wall distal to a prosthetic graft produces increased levels of these arachidonic acid metabolites. However, only those arteries not surgically dissected maintain a normal balance of prostacyclin and thromboxane A2. The dissected artery may thus be more susceptible to platelet interaction and myointimal hyperplasia.

Abnormal VIII: von Willebrand factor patterns in the plasma of patients with the hemolytic-uremic syndrome

Plasma VIII:von Willebrand factor antigen (VIII:vWF) levels were elevated approximately two- to eightfold in seven patients (three adults and four children) during acute episodes of thrombocytopenia, renal failure, and hemolytic anemia (the hemolytic-uremic syndrome, HUS). In all seven patients, there was an alteration in plasma VIII:vWF patterns during these acute HUS episodes, so that the largest VIII:vWF forms were relatively decreased. Plasma VIII:vWF multimer patterns returned to normal, or nearly to normal, as platelet counts returned to preexisting levels, even in the patients whose recovery of renal function was incomplete and whose plasma VIII:vWF antigen level remained above normal. The sister of one of the HUS patients had a similar clinical prodrome (gastroenteritis) that was not followed by thrombocytopenia or renal failure and was not accompanied by an elevated level or abnormal forms of plasma VIII:vWF. These results suggest that an alteration in VIII:vWF metabolism, distribution, or interaction with platelets is associated with acute HUS episodes. In contrast to patients with chronic relapsing thrombotic thrombocytopenic purpura, none of the HUS patients (either during or after the acute HUS episodes) had a defect in the conversion of unusually large VIII:vWF multimers derived from endothelial cells to the VIII:vWF forms found in normal plasma.

Favorable balance of prostacyclin and thromboxane A2 improves early patency of human in situ vein grafts

Graft thrombosis soon after reconstruction remains a major obstacle to the use of reversed vein grafts in infrapopliteal reconstruction. Our clinical experience with in situ vein grafts corroborates Leather's results by demonstrating an overall graft patency of 95% below the knee at 1 year and 94% in the infrapopliteal group. It has been postulated that this improved early patency rate of in situ vein grafts is the result of more optimal preservation of the endothelium of the vein graft. To investigate this hypothesis, human saphenous veins were handled by an in situ and a reversed technique. The intact vein segments were then tested for luminal production of prostacyclin and thromboxane A2 and fixed for scanning electron microscopic analysis of the surface morphology. This study demonstrated that endothelial cell prostacyclin release is enhanced in human in situ vein segments but not in reversed vein segments. In addition, luminal production of thromboxane A2 is significantly greater in the reversed than in the in situ vein segments. These findings are associated with marked endothelial structural damage in the reversed veins and minimal endothelial disruption in the in situ veins. Therefore the ratio of the antiaggregatory vasodilator prostacyclin to the proaggregatory vasoconstrictor thromboxane A2 is significantly more favorable for the in situ vein segment than for the reversed vein segment. The observed excellent early patency of the in situ vein grafts in our poor-risk patient population may in part be the result of this favorable balance of prostacyclin and thromboxane A2 and the more optimally preserved endothelial morphology.

Inhibition of prostacyclin synthesis in endothelial cells by methylisobutylxanthine is not mediated through elevated cAMP level

Methylisobutylxanthine (MIX) raised cAMP levels and inhibited prostacyclin synthesis and arachidonic acid release in endothelial cells from both pig aorta and human umbilical vein. These effects were reversible and dose dependent on MIX concentrations. Dibutyryl cAMP (3 mM) alone did not inhibit prostacyclin synthesis or arachidonic acid release. When added with MIX, dibutyryl cAMP did not enhance the inhibition elicited by MIX. MIX inhibited the formation of lysophospholipids, 1,2-diacylglycerol and phosphatidic acid in bradykinin-stimulated pig endothelial cells, suggesting that the inhibition of prostacyclin synthesis resulted from an apparent inhibition of both phospholipase A2 and phospholipase C. Other phosphodiesterase inhibitors, theophylline and mopidamole, also raised cAMP levels and inhibited arachidonic acid release. However, there was no correlation between cAMP levels and these inhibitions. Forskolin, an adenylate cyclase activator, elevated intracellular cAMP levels with no apparent inhibition on prostacyclin synthesis. We conclude that the inhibitory effect of MIX on phospholipase A2 and phospholipase C is probably through mechanisms other than the elevation of the cAMP level.

The activation of phosphatidylinositol-hydrolyzing phospholipase A2 during prostaglandin synthesis in transformed mouse BALB/3T3 cells

To investigate the type of phospholipase activated by agents that stimulate prostaglandin synthesis, we used transformed mouse cells whose phospholipids were doubly labeled with [14C]inositol and [3H]arachidonic acid. [14C]Inositol was incorporated mostly into the phosphatidylinositol and [3H]arachidonic acid was distributed into the various phospholipids. When these cells were incubated with bradykinin, a stimulator of prostaglandin synthesis, the release of 3H radioactivity from cellular phospholipids and the synthesis of prostaglandin were initiated within seconds and reached a maximum in 40 to 70 s. Analysis of the intracellular lipids revealed a concomitant increase of radioactivity associated with lysophosphatidylinositol, which was detectable within 5 s of incubation with bradykinin and reached a maximum between 40 and 70 s. Lysophosphatidylinositol which could be formed either from a phospholipase A1 or phospholipase A2 reaction, was identified by its chromatographic properties and conversion to glycerophosphorylinositol. We found that the 3H/14C ratio of purified lysophosphatidylinositol was 1/11 of that of phosphatidylinositol, which indicated that lysophosphatidylinositol formed in response to bradykinin is 1-acyl-sn-glycero-3-phosphorylinositol and most probably is formed from a phospholipase A2 deacylation of phosphatidylinositol (a phospholipase A1 deacylation would result in the formation of lysophosphatidylinositol of a 3H/14C ratio similar to phosphatidylinositol). Furthermore, we did not detect between control and stimulated cells any significant difference in the level of several phospholipase C metabolites including inositol phosphate, diglyceride, and phosphatidic acid. These results suggest that phospholipase C is probably not activated. The formation of lysophosphatidylinositol was also stimulated by thrombin and ionophore A23187, both activators of prostaglandin synthesis. Dexamethasone, a lipase inhibitor, inhibited the appearance of lysophosphatidylinositol, whereas aspirin and low concentrations of indomethacin, the cyclooxygenase inhibitor, did not inhibit. The results presented in ths paper provide evidence that a phospholipase A2-hydrolyzing phosphatidylinositol is activated when intact cells are stimulated for prostaglandin synthesis.

Tranylcypromine and 15-hydroperoxyarachidonate affect arachidonic acid release in addition to inhibition of prostacyclin synthesis in calf aortic endothelial cells

In this paper, we examined the effect of two known inhibitors of prostacyclin synthetase, tranylcypromine and 15-hydroperoxyarachidonate, on bradykinin-stimulated prostacyclin synthesis and arachidonic acid release from cellular phospholipids in endothelial cells derived from calf aorta. These two inhibitors inhibit prostacyclin synthesis stimulated by bradykinin, arachidonic acid, and ionophore A23187. However, these two inhibitors also affect the release of arachidonic acid from cells. Using cells prelabeled with [3H]arachidonic acid, we found that bradykinin-stimulated arachidonic acid release is severely inhibited by tranylcypromine (500 microgram/ml) but is stimulated by 15-hydroxyperoxyarachidonate at a concentration as low as 1 microgram/ml. We also found that 15-hydroperoxyarachidonate inhibits not only prostacyclin formation but also prostaglandin formation from the released arachidonic acid. Under the conditions used, these two compounds have no effects on the cell viability as judged by trypan blue exclusion test. We conclude that tranylcypromine and 15-hydroperoxyarachidonate not only inhibit prostacyclin synthesis but also affect other steps in the metabolism of arachidonic acid in whole cells.

Specificity of phospholipases in methylcholanthrene-transformed mouse fibroblasts activated by bradykinin, thrombin, serum, and ionophore A23187

Methylcholanthrene-transformed mouse fibroblasts synthesize prostaglandins in response to bradykinin, thrombin, serum, and the ionophore A23187. These agents activate phospholipases, thereby releasing fatty acids from phospholipids. To examine the phospholipid specificity of the phospholipases activated by bradykinin, thrombin, serum, and A23187, cells were labeled with [14C]arachidonic acid and stimulated with these agents in the presence of delipidated bovine serum albumin. Phospholipid classes were resolved by two-dimensional chromatography on silica gel-coated paper. Only phosphatidylinositol and phosphatidylcholine lost radioactivity upon stimulation. To characterize the fatty acid specificity of the phospholipases, cells were incubated with 14C-labeled stearic, oleic, linoleic, eicosatrienoic, or arachidonic acid and then exposed to the stimuli. Bradykinin, thrombin, and serum caused specific release of radioactivity into the medium only from cells labeled with arachidonic acid or eicosatrienoic acid, whereas A23187 caused release from cells labeled with any one of the five fatty acids. We conclude that bradykinin, thrombin, and serum activate phospholipases that specifically hydrolyze arachidonyl and eicosatrienoyl phosphatidylinositol and phosphatidylcholine, whereas A23187 is less specific activator of phospholipases.

Arachidonic acid level in cellular lipids determines the amount of prostaglandins synthesized during cell growth in tissue culture

Methylcholanthrene transformed mouse fibroblast cells can be induced to synthesize prostaglandins by a short term incubation with various vasoactive agents including serum, bradykinin and thrombin or in response to mechanical detachment from the culture dish. The ability of the cells to synthesize prostaglandins upon stimulation changes during growth of the culture on the dish; the response is maximal on the first day after inoculation and decreased sharply thereafter. Feeding of the cells with fresh growth medium enhances prostaglandin production induced by all stimuli. The difference in the cell response during growth is probably not due to change of prostaglandin synthetase activity since the specific enzyme activities assayed with microsomal preparations of cells harvested from the first and third day culture are similar. However, analysis of the cellular content of arachidonic acid after saponification of the total lipid extract of cells harvested at different days of growth reveals that the level of arachidonic acid per cell during growth is parallel to the response to stimuli. It is maximal on the first day and decreases sharply on the second day and stays low on the third day. Our study suggests that the level of arachidonic acid in the cell governs the extent of prostaglandin synthesis upon stimulation.

Analogues of anthracene, phenanthrene, and benzoflavone inhibit prostaglandin biosynthesis by cells in culture

Prostaglandin production by methylcholanthrene-transformed 3T3 mouse fibroblasts (MC5-5), human normal fibroblasts (D550), and canine kidney (MDCK) cells was inhibited by several analogues of anthracene, phenanthrene, and benzoflavone. Among the most effective inhibitors of MC5-5's prostaglandin production were anthracene (ID50=1.7 micrometer), 9,10-diaminophenanthrene (ID50=0.48 micrometer), and 7,8-benzoflavone (ID50=0.55 micrometer). Under identical conditions, the ID50's for indomethacin and aspirin were 0.049 and 8.9 micrometer respectively. Production of radioactive prostaglandins by MC5-5 cells from tritiated phospholipids was blocked by 7,8-benzoflavone, but not the release of radioactive arachidonic acid.

Prostaglandin production by methylcholanthrene-transformed mouse BALB/3T3. Requirement for protein synthesis

Stimulation of prostaglandin synthesis in transformed mouse fibroblasts by serum, thrombin, and bradykinin was blocked by actinomycin D and cycloheximide. These RNA and protein synthesis inhibitors did not affect prostaglandin synthetase in vitro or in vivo; nor did they affect the acylation of arachidonic acid into phospholipids. Serum-stimulated release of arachidonic acid and prostaglandins from [3H]arachidonic acid-labeled cells also was inhibited by actinomycin D and cycloheximide. RNA and protein synthesis appear to be required for expression of phospholipase activity; a prerequisite for prostaglandin synthesis by these cells.

Elevated prostaglandins synthetase activity in methylcholanthrene-transformed mouse BALB/3T3

Cell lines transformed from 3T3 spontaneously, by radiation, or by treatment with chemical carcinogens, polyoma and SV40 virus produce up to 5 times more prostaglandins than their untransformed parent line. Several aspects of prostaglandin biosynthesis by MC5-5 and 3T3 were compared. When stimulated by serum, bradykinin, or thrombin, MC5-5 cells labeled with radioactive arachidonic acid in their cellular lipids, these higher levels were shown not to be due to increased availability of the prostaglandin precursor, arachidonic acid. Prostaglandin synthetase activity in microsomal fractions prepared from MC5-5 was 6 times higher than that of microsomes of untransformed cells. The increased prostaglandin levels produced by transformed cells therefore appear to be the result of elevated prostaglandin synthetase activity.

Stimulation of prostaglandin synthesis by bradykinin and thrombin and their mechanisms of action on MC5-5 fibroblasts

Transformed mouse fibroblasts, in which [3H]arachidonic acid was incorporated in the cellular lipids, released radioactive materials into the medium when stimulated by bradykinin and thrombin. Most of this released radioactivity was found in the landins; the remainder was present in the arachidonic acid fraction. When the cells stimulated by serum or when they were mechanically manipulated, not only prostaglandins but also high levels of arachidonic acid were released. Anti-inflammatory steroids, which decrease the availability of arachidonic acid, inhibited the stimulated release of prostaglandins caused by the vasoactive agents, suggesting that bradykinin and thrombin stimulated prostaglandin synthesis by increasing deacylation of the phospholipids. The efficiency of the conversion of the released arachidonic acid into prostaglandins appears to reflect the cellular proximity of the phospholipid deacylating activity and prostaglandin synthesizing system.

Inhibition of arachidonic acid release from cells as the biochemical action of anti-inflammatory corticosteroids

Serum stimulates the production of prostaglandins by transformed mouse fibroblasts. Hydrocortisone (cortisol) inhibits this stimulation. The half-maximal inhibition occurs at 6x10-9 M. Studies with cells labeled with [3H]arachidonic acid in their lipids show that the stimulation by serum results in the release of arachidonic acid from the cellular lipids, mostly phospholipids. Hydrocrotisone inhibits this release but does not inhibit the production of prostaglandins from exogenously supplied arachidonic acid. This inhibition of arachidonic acid release from phospholipids may be the mechanism for the anti-inflammatory action of corticosteroids.

Stimulation of prostaglandin biosynthesis by vasoactive substances in methylcholanthrene-transformed mouse BALB/3T3

Prostaglandins E2 and F2alpha are present in the culture medium of methylcholanthrene-transformed mouse BALB/3T3 cells. The production of these prostaglandins is stimulated when the cells are incubated in the presence of serum, arachidonic acid, thrombin, and bradykinin, or if they are mechanically manipulated. Whereas the appearance of prostaglandins resulting from the latter four treatments is complete in several minutes, in the presence of serum the prostaglandin levels are still increasing ever after 2 hours. Stimulation by all of these treatments is additive. Indomethacin inhibits these stimulations, suggesting that the production of prostaglandins results from de novo biosynthesis.

A 3,5-diaminohexanoate-decomposing Brevibacterium

An obligately aerobic bacterium that grows on dl-erythro-3, 5-diaminohexanoate as a sole carbon, nitrogen, and energy source was isolated by the enrichment culture method. The organism utilizes only the l isomer by means of an inducible enzyme system. The organism has been tentatively identified as a member of the genus Brevibacterium.