Downsizing and purchases of psychotropic drugs: A longitudinal study of stayers, changers and unemployed

BACKGROUND

The evidence is insufficient regarding the association between organizational downsizing and employee mental health. Our aim was to analyze trajectories of prescribed sedatives and anxiolytics with a sufficiently long follow-up time to capture anticipation, implementation and adaption to a downsizing event among stayers, changers and those who become unemployed compared to unexposed employees.

METHOD

Residents in Sweden aged 20-54 years in 2007, with stable employment between 2004 and 2007, were followed between 2005 and 2013 (n = 2,305,795). Employment at a workplace with staff reductions ≥18% between two subsequent years in 2007-2011 (n = 915,461) indicated exposure to, and timing of, downsizing. The unexposed (n = 1,390,334) were randomized into four corresponding sub-cohorts. With generalized estimating equations, we calculated the odds ratios (OR) of purchasing prescribed anxiolytics or sedatives within nine 12-month periods, from four years before to four years after downsizing. In order to investigate whether the groups changed their probability of purchases over time, odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated contrasting the prevalence of purchases during the first and the last 12-month period within four time periods for each exposure group.

RESULTS

The odds of purchasing psychotropic drugs increased more for changers (sedatives OR 1.08, 95% CI 1.05-1.11) and unemployed (anxiolytics OR 1.08, 95% CI 1.03-1.14), compared to unexposed before downsizing, while for stayers purchases increased more than for unexposed during and after downsizing. Among those without previous sickness absence, stayers increased their purchases of psychotropic drugs from the year before the event up to four years after the event.

CONCLUSION

This study indicates that being exposed to downsizing is associated with increased use of sedatives and anxiolytics, before the event among those who leave, but especially thereafter for employees who stay in the organization.

Associations between COVID-19-related changes in the psychosocial work environment and mental health

BACKGROUND

Individuals' lives have been substantially affected by the COVID-19 pandemic. We aimed to describe changes in psychosocial work environment and mental health and to investigate associations between job insecurity and mental ill-health in relation to changes in other psychosocial work factors, loneliness and financial worries.

METHODS

A sub-sample of individuals from the eighth Swedish Longitudinal Occupational Survey of Health answered a web-based survey in early 2021 about current and pandemic-related changes in health, health behaviours, work and private life. We investigated participants working before the pandemic (N=1231) in relation to standardised measures on depression, anxiety and loneliness, together with psychosocial work factors, in descriptive and logistic regression analyses.

RESULTS

While 9% reached the clinical threshold for depression and 6% for anxiety, more than a third felt more worried, lonelier or in a low mood since the start of the pandemic. Two per cent had been dismissed from their jobs, but 16% experienced workplace downsizings. Conditioning on socio-demographic factors and prior mental-health problems, the 8% experiencing reduced job security during the pandemic had a higher risk of anxiety, but not of depression, compared to employees with unaltered or increased job security. Loneliness and other psychosocial work factors explained more of the association than objective measures of job insecurity and financial worries.

CONCLUSIONS

Reduced job security during the COVID-19 pandemic seems to have increased the risk of anxiety among individuals with a strong labour market attachment, primarily via loneliness and other psychosocial work factors. This illustrates the potentially far-reaching effects of the pandemic on mental health in the working population.

Job loss and job instability during the COVID-19 pandemic and the risk of depression and anxiety among Swedish employees

The COVID-19 pandemic led to permanent and temporary job losses but the mental health consequences of different types of employment transitions are not well-understood. In particular, knowledge is scarce concerning furloughs, which was a common job protection strategy in many high- and upper middle-income countries during this crisis. This study focuses on how different types of job instability and job loss during the pandemic influences depression and anxiety in the context of Sweden. A subset of participants from the Swedish Longitudinal Occupational Survey of Health were contacted in February 2021 and again in February 2022. A total of 1558 individuals participated in either or both waves and worked before the pandemic. We examined whether i) workplace downsizing, ii) furlough, or iii) unemployment/job loss were associated with depression and anxiety over this one-year period during the pandemic. Logistic regression models with cluster-robust standard errors were estimated, adjusting for sociodemographic factors and prior mental health problems. Effect modification by sex and prior mental health problems was also examined. In comparison to stable employment, being furloughed was unrelated to mental health, while experiencing workplace downsizing during the pandemic was associated with an increased risk of anxiety (adjusted Odds Ratio (OR) = 2.09, 95% Confidence interval (CI) = 1.08-4.05). Job loss/unemployment increased the risk of depression (OR = 1.91, 95% CI = 1.02-3.57) compared to being stably employed, but the risk estimate crossed unity when considering prior mental health status. No effect modification by sex or by prior mental health problems was found. This study found that while job loss and downsizing during the COVID-19 pandemic were associated with depression and anxiety, respectively, being furloughed was not. These findings thus suggest that job retention schemes in the form of short-time work allowances, as implemented in Sweden during the COVID-19 pandemic, may prevent mental health problems among employees during economic crises.

Perceived job insecurity and risk of suicide and suicide attempts: a study of men and women in the Swedish working population

Objective

Whether perceived job insecurity increases the risk of suicidal behaviors is unclear. Improved understanding in this area could inform efforts to reduce suicide risk among those experiencing elevated job insecurity during the COVID-19 pandemic as well as post-pandemic. We aimed to investigate if perceived job insecurity predicted increased risk of suicide mortality and suicide attempts.

Method

Employees (N=65 571), representative of the Swedish working population who participated in the Swedish Work Environment Survey in 1991–2003, were followed up through 2016 in the National Inpatient and Death Registers. Suicide deaths and suicide attempts were defined according to International Classification of Diseases (ICD) 10 and ICD-8/9 codes of underlying cause of death and in-/outpatient care. Job insecurity and subsequent risk of suicide and suicide attempt were investigated with marginal structural Cox regression analyses and inverse probability of treatment weighting to control for confounding.

Results

Perceived job insecurity was associated with an elevated risk of suicide [hazard ratio (HR) 1.51, 95% confidence interval (CI) 1.03–2.20], but not with incident suicide attempts (HR 1.03, CI 0.86–1.24). Estimates remained similar after considering prevalent/previous poor mental health, other work factors, and when restricting the follow up time to ten years.

Conclusion

The study suggests that job insecurity is associated with an increased risk of suicide mortality. Concerns about elevated job insecurity and suicide levels in the wake of the current pandemic could thus be considered in strategies to reduce the population health impact job insecurity both during and following the COVID-19 pandemic.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Labor market exit around retirement age in Sweden and trajectories of psychotropic drugs in a context of downsizing

Background

A maintained psychological wellbeing is important in order to continue working longer and remain active into older age. However, little is known about impact of different organizational factors, such as downsizing, on the mental health of older workers exiting the labor market. The aim in this study was to investigate trajectories of purchases of psychotropic drugs in relation to labor market exit later in life in a context with and without downsizing.

Method

People living in Sweden, born 1941–1951, exiting paid work via unemployment, sickness absence/disability pension, or old-age pension were followed from 2005 to 2013 regarding purchases of psychotropic drugs. Individuals employed at a workplace closing down or downsizing with ≥18% between two subsequent years were compared to employees exiting from workplaces without downsizing or workplace closure. Generalized estimating equations was applied to derive trajectories of annual prevalence of purchased antidepressants, sedatives and anxiolytics from 4 years before to 4 years after a labour market exit.

Results

During the period around the exit, old-age retirees experiencing a downsizing/workplace closure did not decrease their purchases of sedatives (OR 1.01 95% CI 0.95–1.07) while the unexposed decreased their purchases during this period (OR 0.95 95% CI 0.92–0.98). Similar differences concerning sedatives and antidepressants between exposed and unexposed were seen for those exiting via sickness absence or disability pension. Furthermore, a significant difference in purchases of anxiolytics was observed between those exposed to downsizing (OR 1.10 95% CI 0.97–1.24) and the unexposed (OR 0.98 95% CI 0.91–1.06) exiting via old-age retirement during the time before the exit.

Conclusion

Downsizing or workplace closure, although weakly, was associated with higher prevalence of psychotropic drugs certain years around the labor market exit. The results support the idea that involuntary labor market exit in mature adulthood may negatively affect the development of mental health.

Associations between cognitive and affective job insecurity and incident purchase of psychotropic drugs: A prospective cohort study of Swedish employees

BACKGROUND

Previous research suggests that job insecurity is associated with poor mental health, but research examining how different aspects of job insecurity relate to clinical measures of poor mental health are lacking. We aimed to investigate the association between cognitive and affective job insecurity and incident purchases of psychotropic drugs.

METHODS

We included 14,586 employees participating in the Swedish Longitudinal Occupational Survey of Health (SLOSH), who answered questions on cognitive and/or affective job insecurity in 2010, 2012 or 2014. Respondents were followed in the Swedish Prescribed Drug Register (2.5 years on average). We investigated the association between job insecurity and incident psychotropic drugs with marginal structural Cox models.

RESULTS

Affective job insecurity was associated with an increased risk of purchasing any psychotropic drugs (Hazard Ratio (HR) 1.40 (95% Confidence Interval (CI) 1.04-1.89)) while cognitive job insecurity was not (HR 1.15 (95% CI 0.92-1.43)). Cognitive and affective job insecurity were both associated with antidepressants, affective job insecurity with anxiolytics, but no association was found with sedatives. Women and younger workers seemed to have higher risk compared to men and older workers, but differences were not statistically significant.

LIMITATIONS

Although job insecurity and psychotropic drugs were assessed through independent sources and several covariates were considered, unmeasured confounding cannot be ruled out.

CONCLUSIONS

The findings support that affective job insecurity is a risk factor for psychotropic drug treatment, that it may be relevant to distinguish between different types of job insecurity, and to consider sex and age as moderating factors.

Downsizing and purchases of psychotropic drugs: A longitudinal study of stayers, changers and unemployed

BACKGROUND

The evidence is insufficient regarding the association between organizational downsizing and employee mental health. Our aim was to analyze trajectories of prescribed sedatives and anxiolytics with a sufficiently long follow-up time to capture anticipation, implementation and adaption to a downsizing event among stayers, changers and those who become unemployed compared to unexposed employees.

METHOD

Swedish residents aged 20-54 years in 2007, with stable employment between 2004 and 2007, were followed between 2005 and 2013 (n = 2,305,795). Employment at a workplace with staff reductions ≥18% between two subsequent years in 2007-2011 (n = 915,461) indicated exposure to, and timing of, downsizing. The unexposed (n = 1,390,334) were randomized into four corresponding sub-cohorts. With generalized estimating equations, we calculated the odds ratios (OR) of purchasing prescribed anxiolytics or sedatives within nine 12-month periods, from four years before to four years after downsizing. In order to investigate whether the groups changed their probability of purchases over time, odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated contrasting the prevalence of purchases during the first and the last 12-month period within four time periods for each exposure group.

RESULTS

The odds of purchasing anxiolytics increased more for stayers (OR 1.03, 95% CI 1.01-1.06) and unemployed (OR 1.08, 95% CI 1.03-1.14) compared to unexposed before downsizing, and purchases continued to increase after downsizing for stayers. Among those without previous sickness absence, stayers increased their purchases of anxiolytics from the year before the event up to four years after the event. Trajectories for sedatives were similar but less pronounced.

CONCLUSION

This study indicates that being exposed to downsizing is associated with increased use of sedatives and anxiolytics, especially before the event, if the employee stays in the organization or becomes unemployed.

Rapid detection and monitoring of human coronavirus infections

Human coronaviruses (CoVs) are increasingly recognized as important respiratory pathogens associated with a broad range of clinical diseases. We sought to increase the insight into clinically relevant CoV infections by monitoring antigen concentrations in six confirmed CoV-positive patients using a newly developed assay for rapid detection of CoV OC43 infections. Antigen positivity lasted 3 to 6 days in secondary infections and 13 days in primary infection. CoV infections are clinically diverse, are common, and cannot be diagnosed from clinical symptoms alone.

Increasing health inequalities between women in and out of work--the impact of recession or policy change? A repeated cross-sectional study in Stockholm county, 2006 and 2010

Introduction

The social insurance system in Sweden underwent extensive change between 2006 and 2010, with the overall aim of making people enter the labour market. At the same time, economic recession hit Sweden. Previous studies suggest that the economic recession particularly affected women. In light of these changes, the aim of this study is to investigate whether health inequalities between employed women and groups outside the labour market changed between 2006 and 2010. A second aim is to examine the explanatory weight of socio-demographic factors vs social and economic conditions.

Methods

Data consists of the Stockholm Public Health Surveys (SPHS) for 2006 and 2010. Women aged 18–64 were studied. Through logistic regression, levels of mental distress and limiting longstanding illness (LLI), were compared between four labour market groups; employed and unemployed, sickness absentees and disability pension recipients, at the two time points.

Results

Mental distress increased among women in all four labour market groups between 2006 and 2010. Differences in mental distress between those employed and groups outside the labour market also increased. These were explained primarily by social and economic conditions. Levels of LLI were unchanged except among the unemployed. The difference in LLI between the unemployed and the employed was mostly explained by social and economic conditions. In the other groups socio-demographic factors were more salient. For both health outcomes, the weight of social and economic conditions had increased in 2010 compared to 2006.

Conclusions

Results indicate that levels of mental distress increased in all groups, but more so among groups outside the labour market, possibly due to stricter eligibility criteria and lower benefit levels, which particularly affected their social and economic conditions.

Highly divergent neurovirulent vaccine-derived polioviruses of all three serotypes are recurrently detected in Finnish sewage

In Finland, surveillance of potential re-emergence of poliovirus transmission is mainly based on environmental surveillance, i.e. search for infectious poliovirus in sewage samples. Since December 2008, 21 genetically highly divergent, neurovirulent vaccine-derived polioviruses (VDPV) have been isolated from sewage in Tampere, Finland. While the source of the VDPV is unknown, characteristics of the viruses resemble those of strains isolated from immunodeficient, persistently infected persons. No cases of suspected poliomyelitis have been reported in Finland since 1985.

Highly divergent neurovirulent vaccine-derived polioviruses of all three serotypes are recurrently detected in Finnish sewage

In Finland, surveillance of potential re-emergence of poliovirus transmission is mainly based on environmental surveillance, i.e. search for infectious poliovirus in sewage samples. Since December 2008, 21 genetically highly divergent, neurovirulent vaccine-derived polioviruses (VDPV) have been isolated from sewage in Tampere, Finland. While the source of the VDPV is unknown, characteristics of the viruses resemble those of strains isolated from immunodeficient, persistently infected persons. No cases of suspected poliomyelitis have been reported in Finland since 1985.

Advanced environmental surveillance and molecular analyses indicate separate importations rather than endemic circulation of wild type 1 poliovirus in Gaza district in 2002

An improved sewage surveillance algorithm (sample acquisition, processing, and molecular analysis) for wild and vaccine-derived polioviruses was developed and validated. It was based on plaque isolation with sensitive and high-throughput methods. The molecular analysis included sequencing; a comparison of the type, rate, and distribution of nucleotide substitutions with a profile for outbreaks evolving from a single progenitor; and phylogenetic analysis for relative similarity. The analyses revealed that two environmental wild type 1 isolates from the Gaza district in 2002 were imported separately, most likely from Egyptian southern governorates, and were not linked by endemic circulation. These findings illustrate the continuous spreading potential of wild-type poliovirus and underscore the value of extensive environmental surveillance employing advanced molecular analysis to monitor wild poliovirus in poliomyelitis-free regions.

Virological and serological analysis of rhinovirus infections during the first two years of life in a cohort of children

The occurrence of rhinovirus infections in a cohort of 329 children during the first 2 years of life was determined by virus detection and serological methods. Rhinovirus detection on nasopharyngeal aspirates and middle ear fluids comprised a combination of virus isolation in HeLa Ohio cells and a reverse transcription-polymerase chain reaction (RT-PCR)-hybridization assay on the inoculated cell cultures. Nasopharyngeal aspirates were collected when the child was referred to the study clinic because of respiratory symptoms. Nasopharyngeal aspirates and middle ear fluids were collected after clinical diagnosis of an acute otitis media. Complement-fixing antibodies to rhinovirus were determined from scheduled serum specimens collected at 6, 12, 18, and 24 months of age and from paired sera taken in the cases of acute otitis media. Rhinovirus infections were shown to be common in infants, 24% of the children had complement-fixing antibodies at the age of 6 months and 22% had had at least one rhinovirus episode indicated by virus detection. At the age of 2 years, 91.3% of the children had rhinovirus-specific antibodies, while 79% of the children had experienced rhinovirus infection as judged by the virus detection tests. However, the complement-fixation assay was poor as a diagnostic test. Of 458 acute otitis media episodes studied, 41% were shown to be associated with a rhinovirus by RT-PCR-hybridization, while significant fourfold rise in rhinoviral antibodies was detected only in 7% of the cases.

Epidemiology of documented viral respiratory infections and acute otitis media in a cohort of children followed from two to twenty-four months of age

BACKGROUND

Viral upper respiratory infections (URIs) are considered major risk factors for acute otitis media (AOM) in young children. We studied the epidemiology and relative roles of different viruses in respiratory infections in a cohort of 329 Finnish children followed from 2 months to 2 years of age.

METHODS

A nasopharyngeal aspirate (NPA) was collected whenever the child had signs and/or symptoms of URI and tested for the presence of common respiratory virus antigens or infectivity/nucleic acid (only rhinoviruses). Possible repeated detections of a given virus during a 30-day period were considered to represent a single designated virus-specific episode. AOM and URI episodes were defined in a similar way.

RESULTS

At least one virus was detected in 837 (41.7%) of the 2005 NPA specimens examined. Rates of URI and virus-specific episodes showed expected seasonal variation with major peak occurrences coinciding with or preceding those of AOM. The proportions of rhinoviruses, respiratory syncytial (RS) virus, parainfluenza virus (PIV) type 3, influenza virus A and adenoviruses were 63.1, 14.7, 6.7, 6.7 and 6.2% of the total of 761 virus-specific episodes. Influenza virus B, PIV1 and PIV2 were each responsible for approximately 1% of the episodes. AOM was diagnosed in 870 URI cases (43.4%) and in 43.3% of cases associated with a virus-positive NPA. The latter figure was clearly higher (57.7%) for RS virus-positive specimens.

CONCLUSIONS

The seasonal coincidence of URI and AOM demonstrated the obvious role of URI in the pathogenesis of AOM. The occurrence of rhinoviruses and RS virus in URI was strikingly more common than that of any other virus tested. Although rhinoviruses were definitely the most frequently found viruses in NPA specimens, the association of RS virus with concurrent AOM was relatively higher than that of any other virus.

Rapid detection of human rhinoviruses in nasopharyngeal aspirates by a microwell reverse transcription-PCR-hybridization assay

A rapid and sensitive microwell reverse transcription (RT)-PCR-hybridization assay was developed to detect human rhinoviruses in clinical specimens and cell culture suspensions. Two hundred three nasopharyngeal aspirates collected from children with symptoms of respiratory disease were analyzed by a classical rolling-tube cell culture method, microwell culture of HeLa Ohio cell monolayers, and RT-PCR with detection of the amplicons in a microwell hybridization assay. The RT-PCR was also done with harvests of the microwell cultures. RNA was extracted with a commercial kit, and the RT-PCR procedure was carried out with microtiter-format equipment. A confirmatory test that exploited a blocking oligonucleotide at the hybridization step was developed to reliably identify marginally positive specimens. Of the 203 nasopharyngeal aspirate specimens, rhinovirus or rhinoviral RNA was detected in 111 specimens (55%). Ninety-eight specimens (48%) were found to be positive by RT-PCR of the original nasopharyngeal aspirates, while the conventional rolling-tube cell culture method yielded 52 (26%) positive specimens. This RT-PCR method with solid-phase hybridization is easy to perform, sensitive, and specific and will be especially useful for analysis of large numbers of clinical specimens.

Viruses and bacteria in the etiology of the common cold

Two hundred young adults with common colds were studied during a 10-month period. Virus culture, antigen detection, PCR, and serology with paired samples were used to identify the infection. Viral etiology was established for 138 of the 200 patients (69%). Rhinoviruses were detected in 105 patients, coronavirus OC43 or 229E infection was detected in 17, influenza A or B virus was detected in 12, and single infections with parainfluenza virus, respiratory syncytial virus, adenovirus, and enterovirus were found in 14 patients. Evidence for bacterial infection was found in seven patients. Four patients had a rise in antibodies against Chlamydia pneumoniae, one had a rise in antibodies against Haemophilus influenzae, one had a rise in antibodies against Streptococcus pneumoniae, and one had immunoglobulin M antibodies against Mycoplasma pneumoniae. The results show that although approximately 50% of episodes of the common cold were caused by rhinoviruses, the etiology can vary depending on the epidemiological situation with regard to circulating viruses. Bacterial infections were rare, supporting the concept that the common cold is almost exclusively a viral disease.

Serum S100 protein: a potential marker for cerebral events during cardiopulmonary bypass

BACKGROUND

There is no simple method to determine the incidence or severity of brain injury after a cardiac operation. A serum marker equivalent to cardiac enzymes is required. S100 protein leaks from the cerebrospinal fluid to blood after cerebral injury. We sought to determine the pattern of release after extracorporeal circulation (ECC).

METHODS

Thirty-four patients without neurologic problems underwent coronary bypass using ECC. Four had carotid stenoses. Nine others underwent coronary bypass without ECC. Serum S100 levels were measured before, during, and after the operation.

RESULTS

S100 was not detected before sternotomy. Postoperative levels of S100 were related to duration of perfusion (r = 0.89, p < 0.001). Patients who did not have ECC had undetectable or fractionally raised levels except in 1 who suffered a stroke. No patient in whom ECC was used suffered an event, but those with carotid stenosis had greater S100 levels.

CONCLUSIONS

S100 protein leaks into blood during ECC and may reflect both cerebral injury and increased permeability of the blood brain barrier. S100 is a promising marker for cerebral injury in cardiac surgery if elevated levels can be linked with clinical outcome.

Serum cholesterol, cholesterol precursors, and plant sterols in hypercholesterolemic subjects with different apoE phenotypes during dietary sitostanol ester treatment

A randomized double-blind study was made in 67 modestly hypercholesterolemic subjects by replacing 50 g of daily dietary fat by the same amount of a rapeseed oil preparation without and with fat-soluble sitostanol esters. The diet became relatively rich in dietary fat (37%) especially in subjects with a low basal calorie intake. The esters were prepared by transesterification of sitostanol with rapeseed oil fatty acids. The effects of sitostanol esters were studied on serum cholesterol and cholesterol synthesis (measuring cholesterol precursors in serum) and absorption (measuring serum plant sterols). The results were related to different apoE phenotypes. A 6-week regimen of about 3.4 g/day of sitostanol lowered total and low density lipoprotein (LDL) cholesterol levels by 7.5% and 10%, respectively, over that due to rapeseed oil alone. High density lipoprotein (HDL) cholesterol and triglyceride concentrations were unchanged. Thus, the HDL/LDL cholesterol ratio was significantly increased. The decrease in LDL cholesterol level was more consistent in subjects with the epsilon 4 allele than in those with homozygous epsilon 3 alleles. Sitostanol markedly decreased serum campesterol (-46%) and sitosterol (-30%), especially in subjects with the epsilon 4 alleles known to have high cholesterol absorption . The decreases of LDL cholesterol and plant sterols were interrelated, suggesting that reduced cholesterol absorption contributed to the lowering of LDL cholesterol. Serum sitostanol was unchanged, while the serum cholesterol precursors, delta 8-cholestenol, desmosterol, and lathosterol, were compensatorily increased by 10% (P < 0.05), most consistently in the subjects with epsilon 4 alleles, indicating an increase in cholesterol synthesis. The study demonstrates that sitostanol esters dissolved in dietary fat can be recommended for treatment of modest primary hypercholesterolemia and are apparently practical and suitable for cholesterol lowering in a general population.

Human plasma phospholipid transfer protein causes high density lipoprotein conversion

The effect of human plasma phospholipid transfer protein (PLTP) on the particle size distribution of human high density lipoprotein (HDL) was studied by incubating human HDL3 (particle diameter, 8.7 nm) together with PLTP in vitro. Incubation of HDL3 with highly purified preparations of PLTP, devoid of cholesterol ester transfer protein (CETP), induced a conversion of the homogenous population of HDL particles into two main populations of particles, one larger, particle diameter 10.9 nm, and one smaller, particle diameter 7.8 nm, than the original HDL3. These size changes were evident as analyzed by gradient gel electrophoresis and by high resolution gel filtration. The degree of the conversion was dependent on the amount of PLTP added to the incubation and on incubation time. An inhibitory monoclonal antibody (TP-1) directed against CETP had no effect on the HDL conversion. The PLTP used was purified to homogeneity from human plasma using ultracentrifugation and a combination of hydrophobic, cation-exchange, heparin-Sepharose-, anion-exchange, and gel filtration chromatographies. The monoclonal anti-CETP antibody (TP-1), which inhibits lipid transfer catalyzed by CETP, did not react with PLTP or inhibit its activity. The estimated molecular weight of PLTP is 75,000. The present study demonstrates that PLTP can act like the putative conversion factor and has the ability to convert HDL3 into populations of larger and smaller HDL particles. The mechanism(s) involved in this process and its physiological relevance remain to be established.

Dynamic pulmonary accumulation of labelled neutrophils by blood membrane contact in the pig

Nine anesthetized pigs were subjected to short (90 min) sham dialysis with blood membrane contact with the aim to select effects of the artificial surface during dialysis. The importance of the neutrophil (PMN) was investigated by the selective isotope labelling, dynamically followed by gamma-camera imaging and biochemical assays specifically oriented for PMN function. These assays included cell count, PMN aggregation, PMN luminescence, fibronectin and catalase activity. Additionally, pulmonary and systemic hemodynamics and acid base balance were monitored. Sham dialysis induced an accumulation of labelled PMN attaining a maximum between 15 and 17 min. This was coupled with a time-related neutropenia, pulmonary vasoconstriction, increased in vitro PMN aggregation and luminescence response. The neutrophil response abated by the end of dialysis. Cardiac output and arterial blood pressure declined to a steady level after 30 min of sham dialysis. There was an insignificant decrease in catalase activity. All other parameters remained unaltered. The results indicate that PMN accumulates in the pulmonary vessels, in association with neutropenia and activation. The transience of the event points to a protective mechanisms of humoral and/or cellular character.

Early post-traumatic changes in hemodynamics and pulmonary ventilation in alcohol-pretreated pigs

Time relations among trauma, pulmonary and systemic circulation, and lung function were studied in pigs. Eleven animals (b.w. 25-30 kg) were investigated under balanced anesthesia. Ventilation was mechanically controlled. Hemodynamics, pulmonary ventilation, and gas exchange were serially recorded. Seven animals were pretreated with 40% ethanol in saline and four with saline only. Ninety minutes after the ingestion of alcohol or saline, the animals were subjected to a standardized soft-tissue trauma. Cardiac output decreased significantly 2 minutes after trauma and remained low in both groups throughout the observation period of 30 minutes. Pulmonary vascular resistance was significantly increased in the alcohol-pretreated group but was virtually unchanged in the control animals. Systemic vascular resistance was similarly reduced in the two groups. Total compliance was somewhat lower in alcohol-pretreated animals and 10 minutes after the trauma arterial oxygen tension was significantly lower in the alcohol group than in control animals. Carbon dioxide elimination was reduced after trauma in both groups. It is concluded that pulmonary vascular response increased and that total pulmonary compliance is somewhat decreased shortly after trauma in the alcohol group while gas exchange is almost unchanged. The results indicate a negative interaction between alcohol and trauma.

Non-specific polyclonal antibody response induced by Mycoplasma pneumoniae

The ability of heat-killed Mycoplasma pneumoniae (MP) organisms to induce polyclonal antibody production in cultures of blood lymphocytes of healthy subjects was studied. MP induced both IgM and IgG production, with a predominance of IgM. Supernatants of MP-stimulated lymphocyte cultures were tested by an enzyme-linked immunosorbent assay for antibodies to measles, rubella, and herpes simplex virus. MP as well as pokeweed mitogen induced production of viral antibodies of IgG class in lymphocytes of donors who had serum antibodies to the corresponding viral antigens. The MP-induced non-specific antibody response was T-cell-dependent. Lymphocytes from four patients with MP pneumonia, collected nine to 13 days after onset of illness, were tested for in vitro Ig production in the absence of MP. These lymphocytes spontaneously produced increased amounts of IgM and/or IgG. Lymphocytes from three of these four patients spontaneously produced viral IgG antibodies to measles and/or varicella antigens, indicating that MP had induced non-specific activation of memory B cells in vivo. Spontaneous viral antibody production was not found in lymphocyte cultures of healthy donors. The non-specific activation of blood B cells in vitro is probably induced by non-specific helper factors from MP-activated T cells. It is possible that in vivo MP also may have a direct activating effect on B cells.