Birth characteristics as predictors of respiratory syncytial virus hospitalisation in newborns to optimise immunisation schedule

AIM

To examine birth characteristics that influence infant respiratory syncytial virus (RSV) hospitalisation risk in order to identify risk factors for severe RSV infections.

METHODS

Retrospective cohort study of 460 771 Sicilian children under 6 months old from January 2007 to December 2017. Hospital discharge records were consulted to identify cases and hospitalisations with International Classification of Diseases, Ninth Revision, Clinical Modification codes 466.11 (RSV bronchiolitis), 480.1 (RSV pneumonia) and 079.6 (RSV). RSV hospitalisation risk was estimated using adjusted odds ratios (aOR) and 95% confidence intervals (95% CI).

RESULTS

Overall, 2420 (5.25 per 1000 infants) RSV-related hospitalisations were identified during the study, with girls accounting for 52.8%. RSV hospitalisation risk increased for full-term, transferred, extreme immature, and preterm neonates with serious issues (aOR 3.25, 95% CI 2.90-3.64; aOR 1.86, 95% CI 1.47-2.32; aOR 1.54, 95% CI 1.11-2.07; and aOR 1.48, 95% CI 1.14-1.90). Compared to children born in June, the risk of RSV hospitalisation was significantly higher in children born in January (aOR 28.09, 95% CI 17.68-48.24) and December (aOR 27.36, 95% CI 17.21-46.99).

CONCLUSION

This study identified birth month and diagnosis-related groups as key predictors of RSV hospitalisations. This could help manage monoclonal antibody appropriateness criteria.

Increase of multidrug-resistant bacteria after the COVID-19 pandemic in a major teaching Hospital in Sicily (2018-2021)

INTRODUCTION

The COVID-19 pandemic has further highlighted the continuing threat of antimicrobial resistance (AMR) to global health and economic development. In the last two decades, AMR has raised increasing concern with an estimated 4.95 million deaths globally due to bacterial AMR in 2019 alone. This study aims to analyze the impact of the pandemic on the spread of multi-drug resistant organisms (MDROs) using data from the Hospital «P. Giaccone» in Palermo, comparing pre-pandemic and pandemic periods.

METHODS

This observational study involved adult patients discharged from the hospital between 01/01/2018-31/12/2021. Hospital Discharge Cards were linked with microbiological laboratory reports to assess MDRO isolations. SARS-CoV-2 positivity during hospitalization was evaluated using the National Institute of Health's surveillance system.

RESULTS

This study evaluated 58,427 hospitalizations, where half of the patients were over 65 years old (N=26,984) and most admissions were in the medical area (N=31,716). During the hospitalization period, the isolated MDRO were 2,681(5%), whereas there were 946 subjects (2%) positive for SARS-CoV-2. In the multivariable analyses, during 2020 and 2021 there was a significant increased risk of isolation of Staphylococcus aureus,Acinetobacter baumannii,and Klebsiella pneumoniae. Age, weight of the Diagnosis Related Group (DRG), wards with higher intensity of care, and length-of-stay were associated to a higher risk of MDRO isolation.

CONCLUSION

Our study provides new insights into the impact of the COVID-19 pandemic on MDRO isolation and has important implications for infection control and prevention efforts in healthcare facilities. Age, DRG-weight, and longer hospital stays further increase the risk of MDRO isolation. Thus, it is imperative to improve and follow hospital protocols to prevent healthcare-associated infections.

Low Risk of SARS-CoV-2 Reinfection for Fully or Boosted mRNA Vaccinated Subjects in Sicily: A Population-Based Study Using Real-World Data

Background: Reinfections occur as a response to natural infections wanes and novel strains of SARS-CoV-2 emerge. The present research explored the correlation between sex, age, COVID-19 vaccination, prior infection hospitalization, and SARS-CoV-2 reinfection in Sicily, Italy. Materials and Methods: A population-based retrospective cohort study was articulated using the vaccination flux from a regional registry and the Sicilian COVID-19 monitoring system of the Italian Institute of Health. Only adult Sicilians were included in the study, and hazard ratios were calculated using Cox regression. Results: Partial vaccination provided some protection (adj-HR: 0.92), when compared to unvaccinated individuals; furthermore, reinfection risk was reduced by full vaccination (adj-HR: 0.43), and the booster dose (adj-HR: 0.41). Males had a lower risk than females of reinfection with SARS-CoV-2 (adj-HR: 0.75). Reinfection with SARS-CoV-2 was diminished by hospitalization during the first infection (adj-HR: 0.78). Reinfection risk was higher among those aged 30-39 and 40-49 compared to those aged 18-29, whereas those aged 60-69, 70-79, and 80+ were statistically protected. Reinfection was significantly more frequent during the wild-type-Alpha, Delta, Delta-Omicron, and Omicron dominance/codominance waves compared to the wild type. Conclusions: This study establishes a solid base for comprehending the reinfection phenomenon in Sicily by pinpointing the most urgent policy hurdles and identifying some of the major factors. COVID-19 vaccination, one of the most effective public health tools, protects against reinfection, mostly caused by the Omicron strain. Elderly and hospitalized people's lower risk suggests stricter PPE use.

Effectiveness of mRNA COVID-19 Vaccines in Adolescents Over 6 Months

BACKGROUND AND OBJECTIVES

On June 4, 2021, Italy launched the coronavirus disease 2019 (COVID-19) vaccination of adolescents to slow down the COVID-19 spread. Although clinical trials have evaluated messenger ribonucleic acid (mRNA) vaccine effectiveness in adolescents, there is limited literature on its real-world effectiveness. Accordingly, this study aimed to estimate the effectiveness of mRNA COVID-19 vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mild or severe COVID-19 in a cohort of Sicilian adolescents within a 6 month observation period.

METHODS

A retrospective cohort study was conducted with adolescents aged 12 to 18 years, residents of Sicily, who were followed from July 15 to December 31, 2021. SARS-CoV-2 infections, mild and severe COVID-19, and COVID-19-related intubation or deaths during the study period were compared between subjects vaccinated with 2 doses of mRNA vaccines and unvaccinated individuals. The Cox regression analysis, adjusted for age and sex, was performed to compare the 2 groups.

RESULTS

Overall, the study included a total at-risk population of 274 782 adolescents with 61.4% of them having completed the vaccination cycle by the end of the study. Unvaccinated subjects had higher incidence rates of SARS-CoV-2 (1043 × 10 000 vs 158.7 × 10 000 subjects), mild COVID-19 (27.7 × 10 000 vs 1.8 × 10 000 subjects) and severe COVID-19 (1.41 × 10 000 vs 0 subjects) compared with the vaccinated population. The estimated adjusted vaccine effectiveness against SARS-CoV-2 infection was 71.2%, reaching 92.1% and 97.9% against mild and severe COVID-19, respectively.

CONCLUSIONS

This study provides rigorous evidence of mRNA COVID-19 vaccines' effectiveness in protecting adolescents from both SARS-CoV-2 infection and COVID-19.

Effectiveness of mRNA COVID-19 Vaccination on SARS-CoV-2 Infection and COVID-19 in Sicily over an Eight-Month Period

In order to reduce the spread of SARS-CoV-2 infection and the burden of disease, since 27 December 2020, Sicily has introduced a regional COVID-19 vaccination campaign. This study aimed at estimating the effectiveness of mRNA COVID-19 vaccines on SARS-CoV-2 infections and COVID-19. A retrospective cohort study was carried out on 3,966,976 Sicilian adults aged 18 years or more, who were followed-up from 1 January 2021 to 30 September 2021. The risk of SARS-CoV-2 infection, severe COVID-19, and COVID-19 death or intubation during the study period was compared among vaccinated with two mRNA doses and unvaccinated individuals. Cox regression, adjusted for age and sex, and a joint-point analysis on rate trends were performed. Overall, 2,469,320 (62.2%) subjects have been vaccinated and a total of 103,078 (2.6% of the entire population) SARS-CoV-2-positive subjects have been observed including 4693 (0.12%) severe COVID-19, 277 (0.01%) intubated, and 2649 (0.07%) deaths. After two months from vaccination, adjusted vaccine effectiveness was 81.3% against SARS-CoV-2 infection, 96.1% against severe COVID-19, and 93.4% against intubation/death. During the eight-month follow-up, statistically significant decreasing effectiveness trends were observed for all the evaluated outcomes (−4.76% per month against SARS-CoV-2 infection; −2.27% per month against severe COVID-19 and −2.26% per month against COVID-19 intubation/death). The study results confirm that mRNA COVID-19 vaccines have high real-world effectiveness, especially in the first months after vaccination. The vaccine effectiveness decreases over time and, even if the decrease is relatively small against severe outcomes, the increasing protection wane suggests the need for booster vaccination campaigns.

Measuring particle size distribution and mass concentration of nanoplastics and microplastics: addressing some analytical challenges in the sub-micron size range

HYPOTHESIS

The implementation of the proposal from the European Chemical Agency (ECHA) to restrict the use of nanoplastics (NP) and microplastics (MP) in consumer products will require reliable methods to perform size and mass-based concentration measurements. Analytical challenges arise at the nanometre to micrometre interface, e.g., 800 nm-10 µm, where techniques applicable at the nanometre scale reach their upper limit of applicability and approaches applicable at the micrometre scale must be pushed to their lower limits of detection.

EXPERIMENTS

Herein, we compared the performances of nine analytical techniques by measuring the particle size distribution and mass-based concentration of polystyrene mixtures containing both nano and microparticles, with the educational aim to underline applicability and limitations of each technique.

FINDINGS

Light scattering-based measurements do not have the resolution to distinguish multiple populations in polydisperse samples. Nanoparticle tracking analysis (NTA), nano-flowcytometry (nFCM) and asymmetric flow field flow fractionation hyphenated with multiangle light scattering (AF4-MALS) cannot measure particles in the micrometre range. Static light scattering (SLS) is not able to accurately detect particles below 200 nm, and similarly to transmission electron microscopy (TEM) and flow cytometry (FCM), is not suitable for accurate mass-based concentration measurements. Alternatives for high-resolution sizing and concentration measurements in the size range between 60 nm and 5 µm are tunable resistive pulse sensing (TRPS) and centrifugal liquid sedimentation (CLS), that can bridge the gap between the nanometre and micrometre range.

PERSONALITY FACTORS OF EMOTIONAL RESILIENCE IN THE CHALLENGING ENVIRONMENTS FOR MENTAL HEALTH

OBJECTIVE

The aim: The article presents the results of an empirical study aimed at identifying individual typological profiles of people with different potential for emotional resilience development.

PATIENTS AND METHODS

Materials and methods: The authors identify a set of characteristics that determine emotional resilience development and suggest standardized methodologies to measure their intensity level (Eysenck Personality Inventory (EPI), Strelau Temperament Inventory (STI), Thurstone Temperament Schedule adapted by Khainovski, and the Leonhard-Schmieschek questionnaire). The outcomes of the data processed in the R environment have allowed the determination of the parameters of the psychological profile of an average client and identification of the traits that have the strongest impact on emotional resilience development.

RESULTS

Results: The constructed factor-correlation-cluster model based on the mean data values for each of the respondents' psychological profiles contains three superclusters: 1) orientation at outer/inner world, 2) behavioral determination stability, 3) reflectivity. Accordingly, six types of psychological profiles of individuals with different potential for emotional resilience development have been determined. The six types are: 1) outward-oriented (looking) type; 2) inward-oriented type; 3) stable behavioral determination type; 4) unstable behavioral determination type; 5) reflectivity-oriented type; 6) reflectivity- non-oriented type. The authors describe the structure and peculiarities of manifestation of the individual psychological characteristics within each supercluster. The behavioral manifestations that facilitate or hinder the development of emotional resilience of individuals belonging to certain profiles are also described.

CONCLUSION

Conclusions: The implementation prospects of the developed typology of psychological profiles of individuals with different emotional resilience resources are related to providing client-oriented support of emotional resilience development. Further research will address the development, piloting and implementation of the socio-psychological strategies of emotional resilience development support based on the suggested psychological profile typology.

CITIZENS OBTAINING PSYCHOSOCIAL SUPPORT DURING THE COVID-19 PANDEMIC IN UKRAINE: A CROSS-SECTIONAL STUDY

OBJECTIVE

The aim: To investigate the obtaining of psychosocial support by citizens during the COVID-19 pandemic in Ukraine using a cross-sectional study assessing the socio-demographic characteristics of the respondents.

PATIENTS AND METHODS

Materials and methods: It was developed and used the authors' questionnaire "Socio-psychological support during the COVID-19 pandemic in Ukraine". Data processing used Nonparametric Mann-Whitney analysis of variance and one-way Kruskal-Wallis analysis of variance (SPSS 26.0).

RESULTS

Results: The study was conducted from October 2020 to May 2021 and sampled 100 individuals. Significant differences in the studied features are revealed. Gender: women have a more prosperous and broader range of contacts to discuss fears and anxieties during quarantine; suffer more from emotional loss; have more need to be heard and to be taken care of, with no criticism; are more experienced in professional psychological help obtaining; communicate with internal migrants more often. Age: young respondents (19-24 y.o.) suffer more from pandemic losses in the areas of spirituality and friendship; however, more often and more effectively use the means of online psychological support; older respondents are more likely to receive support from an important community and through meditation. Living conditions: living alone, citizens experience more pandemic stress, suffer from losses in personal life and friendship, and consider participation in challenge activities as the most convenient form of support. Place of residence: living in the rural areas is associated with a narrow circle of citizens' contacts to discuss their plans for leisure; more significant damage from pandemic losses in health; lack of support in the form of understanding themselves and their conditions. Education: higher education affects a broader circle of communication; more minor financial losses; willingness to share traumatic stories for art therapy. Financial satisfaction promotes the exchange of ideas between users of online psychological support.

CONCLUSION

Conclusions: The identified conditionality of psychosocial support obtaining by socio-demographic indicators can be used in the development of psychosocial support interventions during a pandemic for Ukrainian citizens by the public and private sectors, particularly in creating specialized smartphone applications, adapting playback theatre in the online space, creating gender-sensitive online programs to integrate IDPs into local communities.

Acute onset of paraganglioma of filum terminale: A case report and surgical treatment

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A very rare case of paraganglioma of filum terminale is described.

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Clinical and radiological features of spinal paraganglioma are listed.

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Surgical management of paraganglioma of filum terminale is discussed.

Introduction

Paragangliomas of filum terminale are rare benign tumors, arising from the adrenal medulla or extra-adrenal paraganglia. These lesions usually present with chronic back pain and radiculopathy and only two cases of acute neurological deficit have been reported in literature.

Presentation of case

A case with an acute paraplegia and cauda equina syndrome due to an hemorrhagic paraganglioma of the filum terminale is described. Magnetic resonance imaging showed an intradural tumor extending from L1 to L2 compressing the cauda equina, with an intralesional and intradural bleed. An emergent laminectomy with total removal of the tumor was performed allowing a post-operative partial sensory recovery. Histopathological examination diagnosed paraganglioma.

Discussion

Paragangliomas are solid, slow growing tumors arising from specialized neural crest cells, mostly occurring in the head and neck and rarely in cauda equina or filum terminale. MRI is gold standard radiological for diagnosis and follow-up of these lesions. They have no pathognomonic radiological and clinical features and are frequently misdiagnosed as other spinal lesions. No significant correlation was observed between the duration of symptoms and tumor dimension. Acute presentation is unusual and emergent surgical treatment is fondamental. The outcome is very good after complete excision and radiotherapical treatment is recommended after an incomplete resection. Conclusion: Early radiological assessment and timely surgery are mandatory to avoid progressive neurological deficits in case of acute clinical manifestation of paraganglioma of filum terminale.

Human factors engineering in healthcare systems: the problem of human error and accident management

This paper discusses some crucial issues associated with the exploitation of data and information about health care for the improvement of patient safety. In particular, the issues of human factors and safety management are analysed in relation to exploitation of reports about non-conformity events and field observations. A methodology for integrating field observation and theoretical approaches for safety studies is described. Two sample cases are discussed in detail: the first one makes reference to the use of data collected in the aviation domain and shows how these can be utilised to define hazard and risk; the second one concerns a typical ethnographic study in a large hospital structure for the identification of most relevant areas of intervention. The results show that, if national authorities find a way to harmonise and formalize critical aspects, such as the severity of standard events, it is possible to estimate risk and define auditing needs, well before the occurrence of serious incidents, and to indicate practical ways forward for improving safety standards.

The complexity of psychiatric comorbidity: a conceptual and methodological discussion

Comorbidity is widely used in psychiatry, although few studies have considered the conceptual and methodological problems deriving from the transposition of this term from medicine to psychiatry. Comorbidity should be defined as two or more diseases, with distinct aetiopathogenesis (or, if the aetiology is unknown, with distinct pathophysiology of organ or system), that are present in the same individual in a defined period of time. In psychiatry, comorbidity is often an artefact for several reasons: (a) different assessment methods; (b) improper utilisation of the term comorbidity to indicate the association of symptoms instead of diseases; (c) number and characteristics of hierarchical exclusion rules used in classification systems; (d) nosologic classification in disorders (a generic term) instead of syndromes (a more precise concept, that allows clinicians to consider the hierarchy and the qualitative specificity of symptoms); (e) excessive splitting of classical syndromes into small disorders with inappropriate and overlapping boundaries; (f) too frequent revision of the diagnostic criteria, that changes diagnostic threshold; (g) number of clinical entities considered. Biological and psychological hypotheses that investigate the complexity of comorbidity findings are here presented; it is underlined that comorbidity should be the epidemiological descriptive starting point to build hypotheses that must be clear and rigorously defined, with specified usefulness and limits. Finally, the hypotheses should be tested with specific methodologies.

Enhanced replication of M-tropic HIV-1 strains in Herpesvirus saimiri immortalised T-cells which express CCR5

A better characterisation of mononuclear cell-tropic (M-tropic) HIV-1 is central to disease control as these viruses predominate in disease transmission. M-tropic viruses do not replicate in conventional T-cell lines, and virus titres obtained in peripheral blood mononuclear cells (PBMC) are low. Human T-lymphocytes which have been immortalised by Herpesvirus saimiri strain C488 (HVS T-cells) are highly permissive to the replication of T-cell tropic strains of HIV. This study aimed to determine if HVS T-cells support replication of M-tropic HIV isolates that have not been adapted to conventional T-cell lines. A panel of PBMC low passage/primary field isolates and their molecular clones was used. Results show that infection in HVS T-cells was longer lived than in PBMC. In terms of peak virus titre and duration of productive infection, the two HVS T-cell lines studied were superior to PBMC, and one supported enhanced replication of all M-tropic isolates. This is important for generating M-tropic virus pools of sufficient titre for further biological studies such as virus neutralisation, co receptor usage and testing of antivirals. Phenotypic analysis showed that HVS T-cells are CD4+-activated memory cells expressing both CXCR-4 and CCR5 co receptors. Thus, HVS immortalisation appears to select for the T-cell subset targeted by HIV-1 in vivo.

Experimental test of harmonic contribution to the thermal index for soft tissue

Experimental data were gathered for the heating effect of an ultrasound beam propagating in water and incident on a thermal test object containing artificial tissue in which a fine-wire thermocouple was embedded close to the beam entrance. The extent of temperature elevations in the artificial tissue was limited by using a constant low value for spatial peak temporal average ultrasound intensity so that the medium did not denature. The adjusted (for continuous wave conditions) maximum temperatures reached in a fixed exposure time initially increased linearly with increase in the spatial peak pulse average ultrasound intensity, but, for the higher values of this parameter, exceeded that expected from a linear relationship. In addition to the fundamental frequency, significant higher frequencies were present in the beam at high intensities, which caused additional enhancement of the ultrasound heating. Calculations of W(DEG) for evaluation of the thermal index should include the evaluation of the heating contributions from all frequencies present in the beam.

Psychopathological considerations on the relationship between bulimia and obsessive-compulsive disorder

The relationship between eating disorders, impulse control disorders and obsessive-compulsive disorder as part of a so-called 'obsessive-compulsive spectrum' is discussed, with particular emphasis on the relationship between eating disorders (particularly bulimia) and obsessive-compulsive disorder. The empirical studies on comorbidity, personality and familiarity are briefly reviewed. Both similarities and differences found in personality, body image, mental rumination, fears, physical exercises, rituals, impulses (bulimic binging and obsessive impulses) and purging behaviors of these patients are discussed from a psychopathological point of view. In particular the importance of distinguishing between obsessive thoughts and prevalent (dominant) thoughts is underlined; the distinctions between repetitive weight controls, physical exercises and purging behaviors of eating disorder patients on the one hand and compulsions on the other, and the distinction between binge impulses and obsessive impulses, are also stressed.

Rapid purification and monitoring of immunoglobulin M from ascites by perfusion ion-exchange chromatography

A purification and on-line monitoring procedure for IgM was developed. Perfusion ion-exchange chromatography was used for rapid purification of IgM from ascites fluid and hybridoma supernatant. Crude ascites was directly loaded onto an ion exchanger. Due to the complexity of IgM, a two-step ion-exchange procedure had to be developed. This procedure involved a rapid cation-exchange chromatography capture step followed by further purification using anion-exchange chromatography. High linear velocities, in excess of 3500 cm/h, enabled separations to be performed under 5 min. Purity of the final product by SDS-PAGE was shown to be greater than 95%. Furthermore, the antibodies retained biological activity as measured by indirect immunofluorescence (IIF) and ELISA. The IgM peak was also monitored on-line using a novel peak tracking approach. This involved placing an antibody column (specific to the IgM) prior to the ion-exchange column and operating the ion-exchange column with and without the antibody column in-line. The missing peak that is identified by comparing the two chromatograms indicates where the IgM elutes.

Principles and methods for the analysis and purification of synthetic deoxyribonucleotides by high-performance liquid chromatography

The need for high-purity oligodeoxyribonucleotides for various applications has resulted in the development of novel synthesis, purification, and analytical techniques. A diversity of methods, including polyacrylamide slab gel electrophoresis, capillary gel electrophoresis, as well as high-performance liquid chromatography (HPLC), have been successfully used to aid in the characterization and isolation of these synthetic compounds. The information contained in this review article primarily details both the theoretical and practical aspects related to the use of HPLC for the analysis and purification of synthetic DNA. In addition, a variety of postsynthesis sample preparation protocols, commonly employed prior to and after HPLC, are described.

Systematic development and validation of sanitization protocols for a chromatographic system designed for biotherapeutics purification

Production of protein therapeutics through the application of genetic engineering and biotechnology techniques requires comprehensive attention to good manufacturing practice and good laboratory practice (GMP/GLP) guidelines for product recovery and purification. Validated clean-in-place procedures are part of the master method and require analysis of microbial bioburden to assess the efficacy of cleaning protocols. This article describes the extensive microbial challenge of a chromatography system, the use of membrane filtration methods for high sensitivity microbial contamination measurement, and the effectiveness of sodium hydroxide and ethanol solutions in achieving multilog reduction of microbial contamination.

Analysis of synthetic oligodeoxyribonucleotides by capillary gel electrophoresis and anion-exchange HPLC

Polyacrylamide slab gel electrophoresis has been traditionally used for the analysis of synthetic oligodeoxyribonucleotides. As the demand for oligonucleotides of high purity has increased, a need for additional high resolution analytical techniques has arisen. This report describes the principles and application of capillary gel electrophoresis and high-performance liquid chromatography for the analysis of synthetic DNA varying in base composition and length. From the results of a series of comparative experiments, the relative advantages and disadvantages of each technique are discussed.

Large-scale purification of plasmid DNA by anion-exchange high-performance liquid chromatography

Numerous methods have previously been reported for the final steps in the large-scale purification of plasmid DNA. Although gel permeation and reverse-phase high-performance liquid chromatography have been utilized for this procedure in the past, the limited capacity of these systems often necessitated multiple rounds of chromatography, especially with the high copy number plasmids commonly in use today. In this paper, the use of the high-capacity, high-resolution Protein-Pak DEAE 8HR column is presented for the large-scale isolation of highly purified plasmid DNA from crude E. coli cell lysates. Up to 5 mg of plasmid DNA have been purified in a single 50-minute chromatography run. The purified DNA demonstrated excellent biological activity as demonstrated by restriction endonuclease digestion, E. coli transformation and DNA-mediated gene transfection of eukaryotic cells.

Oxygen-related prostaglandin synthesis in ductus arteriosus and other vascular cells

We compared oxygen-related prostaglandin synthesis in fetal lamb ductus arteriosus (DA) pulmonary artery (PA) and aorta endothelial and smooth muscle cells. We measured basal synthesis of 6-keto-PGF1 alpha and PGE2, the response to calcium ionophore (A23187), a nonspecific stimulus of prostaglandin production, as well as the response to oxygen, a perinatal stimulus, monitoring both the effects of hyperoxia (95% O2) and hypoxia (2% O2). In addition, we established whether differences observed in fetal lamb PA cells related to oxygen tension were also observed in newborn central and microvessel PA cells. Our results indicate that DA endothelial cells increase 6-keto-PGF1 alpha in response to ionophore (p less than 0.05). With hyperoxia, DA endothelial cells increase PGE2 synthesis and DA smooth muscle cells increase 6-keto-PGF1 alpha (p less than 0.05 and 0.02, respectively). Aorta smooth muscle cells increase 6-keto-PGF1 alpha in response to ionophore and hyperoxia (p less than 0.003 and 0.05, respectively). PA endothelial and smooth muscle cells have higher levels of basal prostaglandin synthesis when compared with DA and aorta. In response to ionophore, increased 6-keto-PGF1 alpha is observed in both PA endothelial and smooth muscle cells (p less than 0.02 and 0.0004, respectively), and PGE2 is increased in PA smooth muscle cells (p less than 0.003). Hypoxia, however, decreases PA smooth muscle production of both 6-keto-PGF1 alpha and PGE2 (p less than 0.02 and 0.01, respectively). Similar observations were made in newborn lamb central and microvessel PA cells.(ABSTRACT TRUNCATED AT 250 WORDS)