Quantifying the Impact of Rare and Ultra-rare Coding Variation across the Phenotypic Spectrum

There is a limited understanding about the impact of rare protein-truncating variants across multiple phenotypes. We explore the impact of this class of variants on 13 quantitative traits and 10 diseases using whole-exome sequencing data from 100,296 individuals. Protein-truncating variants in genes intolerant to this class of mutations increased risk of autism, schizophrenia, bipolar disorder, intellectual disability, and ADHD. In individuals without these disorders, there was an association with shorter height, lower education, increased hospitalization, and reduced age at enrollment. Gene sets implicated from GWASs did not show a significant protein-truncating variants burden beyond what was captured by established Mendelian genes. In conclusion, we provide a thorough investigation of the impact of rare deleterious coding variants on complex traits, suggesting widespread pleiotropic risk.

Comorbidity of autoimmune thyroid disorders and psychiatric disorders during the postpartum period: a Danish nationwide register-based cohort study

BACKGROUND

The postpartum period is well-known risk period for the first onset of autoimmune thyroid disorders (AITDs) as well as first onset of psychiatric disorders. These two disorders are some of the most prevalent medical conditions postpartum, often misdiagnosed and disabling if left untreated. Our study was designed to explore the possible bidirectional association between AITDs and psychiatric disorders during the postpartum period.

METHODS

A population-based cohort study through linkage of Danish national registers, which comprised 312 779 women who gave birth to their first child during 1997-2010. We conducted Poisson regression analysis to estimate the incidence rate ratio (IRR) of psychiatric disorders among women with first-onset AITDs, the IRR of AITDs among women with first-onset psychiatric disorders as well as the overlap between these disorders using a comorbidity index.

RESULTS

Women with first-onset AITDs postpartum were more likely to have first-onset psychiatric disorders than women who did not have postpartum AITDs (IRR = 1.88, 95% confidence interval (CI): 1.25-2.81). Women with first-onset postpartum psychiatric disorders had a higher risk of AITDs than women with no psychiatric disorders (IRR = 2.16, 95% CI: 1.45-3.20). The comorbidity index 2 years after delivery was 2.26 (95% CI: 1.61-2.90), indicating a comorbidity between first-onset AITDs and psychiatric disorders.

CONCLUSIONS

First-onset AITDs and psychiatric disorders co-occur in the postpartum period, which has relevance to further studies on the etiologies of these disorders and why childbirth in particular triggers the onset.

Individual and combined effects of maternal anemia and prenatal infection on risk for schizophrenia in offspring

BACKGROUND

Maternal iron deficiency and infection during pregnancy have individually been associated with increased risk of schizophrenia in the offspring, but possible interactions between the two remain unidentified thus far. Therefore, we determined the individual and combined effects of maternal infection during pregnancy and prepartum anemia on schizophrenia risk in the offspring.

METHODS

We conducted a population-based study with individual record linkage of the Danish Civil Registration System, the Danish Hospital Register, and the Central Danish Psychiatric Register. In a cohort of Danish singleton births 1,403,183 born between 1977 and 2002, 6729 developed schizophrenia between 1987 and 2012. Cohort members were considered as having a maternal history of anemia if the mother had received a diagnosis of anemia at any time during the pregnancy. Maternal infection was defined based on infections requiring hospital admission during pregnancy.

RESULTS

Maternal anemia and infection were both associated with increased risk of schizophrenia in unadjusted analyses (1.45-fold increase for anemia, 95% CI: 1.14-1.82; 1.32-fold increase for infection, 95% CI: 1.17-1.48). The effect of maternal infection remained significant (1.16-fold increase, 95% CI: 1.03-1.31) after adjustment for possible confounding factors. Combined exposure to anemia and an infection increased the effect size to a 2.49-fold increased schizophrenia risk (95% CI: 1.29-4.27). The interaction analysis, however, failed to provide evidence for multiplicative interactions between the two factors.

CONCLUSION

Our findings indicate that maternal anemia and infection have additive but not interactive effects, and therefore, they may represent two independent risk factors of schizophrenia.

Somatic diseases and conditions before the first diagnosis of schizophrenia: a nationwide population-based cohort study in more than 900 000 individuals

OBJECTIVE

Schizophrenia is associated with excess physical comorbidity. Yet, to our knowledge, large studies are lacking on the associations with somatic diseases before the onset of schizophrenia. The authors conducted a nationwide study of the full spectrum of treated somatic diseases before the first diagnosis of schizophrenia.

METHOD

Nationwide sample of the Danish population consisting of singletons (n = 954351) born 1977-1993 and followed from birth to 2009, during which period 4371 developed schizophrenia. Somatic diagnoses at all general hospital contacts (admitted or outpatient care at a somatic hospital) from 1977 to 2009 were used as exposures. The incidence rate ratio (IRR) of schizophrenia was calculated using Poisson regression adjusted for confounders.

RESULTS

Among the 4371 persons who developed schizophrenia from 1992 to 2009, a total of 4180 (95.6%) persons had a previous somatic hospital contact. A history of any somatic hospital contact was associated with an elevated risk of schizophrenia (IRR = 2.04, 95% CI = 1.77-2.37). A wide range of somatic diseases and conditions were associated with an increased risk of schizophrenia, including epilepsy (IRR = 2.26, 95% CI = 1.93-2.62), nutritional or metabolic disorders (IRR = 1.57, 95% CI = 1.39-1.77), circulatory system diseases (IRR = 1.63, 95% CI= 1.38-1.92), and brain injury (IRR = 1.58, 95% CI = 1.45-1.72).

CONCLUSIONS

A wide range of potential etiological factors could have contributed to the observed associations, including genetic or physiological overlaps between conditions, and interacting immunological, behavioral, and neurodevelopmental factors.

Obsessive-compulsive disorder as a risk factor for schizophrenia: a nationwide study

IMPORTANCE

Despite a remarkable co-occurrence of obsessive-compulsive disorder (OCD) and schizophrenia, little is known about the clinical and etiological relationship of these 2 disorders. Exploring the degree to which these disorders share etiological factors might provide useful implications for clinicians, researchers, and those with the disorders.

OBJECTIVES

To assess whether patients with OCD experience an enhanced risk of developing schizophrenia and schizophrenia spectrum disorders and to determine whether a family history of OCD constitutes a risk factor for schizophrenia and schizophrenia spectrum disorders.

DESIGN, SETTING, AND PARTICIPANTS

Using individual data from longitudinal nationwide Danish registers, we conducted a prospective cohort study with 45 million person-years of follow-up. All survival analyses were adjusted for sex, age, calendar year, parental age, and place of residence at the time of birth. A total of 3 million people born between January 1, 1955, and November 30, 2006, were followed up from January 1, 1995, through December 31, 2012. During this period, 30 556 people developed schizophrenia or schizophrenia spectrum disorders.

MAIN OUTCOMES AND MEASURES

The presence of a prior diagnosis of OCD and the risk of a first lifetime diagnosis of schizophrenia and a schizophrenia spectrum disorder assigned by a psychiatrist in a hospital, outpatient clinic, or emergency department setting. Incidence rate ratios (IRRs) and accompanying 95% confidence intervals are used as measures of relative risk.

RESULTS

The presence of prior diagnosis of OCD was associated with an increased risk of developing schizophrenia (IRR = 6.90; 95% CI, 6.25-7.60) and schizophrenia spectrum disorders (IRR = 5.77; 95% CI, 5.33-6.22) later in life. Similarly, offspring of parents diagnosed as having OCD had an increased risk of schizophrenia (IRR = 4.31; 95% CI, 2.72-6.43) and schizophrenia spectrum disorders (IRR = 3.10; 95% CI, 2.17-4.27). The results remained significant after adjusting for family history of psychiatric disorders and the patient's psychiatric history.

CONCLUSIONS AND RELEVANCE

A diagnosis of OCD was associated with higher rates of schizophrenia and schizophrenia spectrum disorders. The observed increase in risk suggests that OCD, schizophrenia, and schizophrenia spectrum disorders probably lay on a common etiological pathway.

Hospital contacts with infection and risk of schizophrenia: a population-based cohort study with linkage of Danish national registers

Infections and immune responses have been suggested to play an important role in the etiology of schizophrenia. Several studies have reported associations between maternal infections during pregnancy and the child's risk of schizophrenia; however, infection during childhood and adolescence unrelated to maternal infection during pregnancy has not been studied to nearly the same extent and the results are far from conclusive. Data were drawn from 2 population-based registers, the Danish Psychiatric Central Register and the Danish National Hospital Register. We used a historical population-based cohort design and selected all individuals born in Denmark between 1981 and 1996 (n = 843 390). We identified all individuals with a first-time hospital contact with schizophrenia from 1991 through 2010. Out of the 3409 individuals diagnosed with schizophrenia, a total of 1549 individuals had had a hospital contact with infection before their schizophrenia diagnosis (45%). Our results indicate that individuals who have had a hospital contact with infection are more likely to develop schizophrenia (relative risk [RR] = 1.41; 95% CI: 1.32-1.51) than individuals who had not had such a hospital contact. Bacterial infection was the type of infection that was associated with the highest risk of schizophrenia (RR = 1.63; 95% CI: 1.47-1.82). Our study does not exclude that a certain type of infection may have a specific effect; yet, it does suggest that schizophrenia is associated with a wide range of infections. This association may be due to inflammatory responses affecting the brain or genetic and environmental risk factors aggregating in families.

Population impact of familial and environmental risk factors for schizophrenia: a nationwide study

Although several studies have examined the relative contributions of familial and environmental risk factors for schizophrenia, few have additionally examined the predictive power on the individual level and simultaneously examined the population impact associated with a wide range of familial and environmental risk factors. The authors present rate ratios (IRR), population-attributable risks (PAR) and sex-specific cumulative incidences of the following risk factors: parental history of mental illness, urban place of birth, advanced paternal age, parental loss and immigration status. We established a population-based cohort of 2,486,646million persons born in Denmark between 1 January 1955 and 31 December 1993 using Danish registers. We found that PAR associated with urban birth was 11.73%; PAR associated with one, respectively 2, parent(s) with schizophrenia was 2.67% and 0.12%. PAR associated with second-generation immigration was 0.70%. Highest cumulative incidence (CI=20.23%; 95% CI=18.10-22.62) was found in male offspring of 2 parents with schizophrenia. Cumulative incidences for male offspring or female offspring of a parent with schizophrenia were 9.53% (95% CI=7.71-11.79), and 4.89%, (95% CI 4.50-5.31). The study showed that risk factors with highest predictive power on the individual level have a relatively low population impact. The challenge in future studies with direct genetic data is to examine gene-environmental interactions that can move research beyond current approaches and seek to achieve higher predictive power on the individual level and higher population impact.

Association between parental hospital-treated infection and the risk of schizophrenia in adolescence and early adulthood

It has been suggested that infection during perinatal life may lie at the etiological root of schizophrenia. It has thus been hypothesized that the origin of schizophrenia may lie either in direct fetal infection and/or in a generally increased familial susceptibility to infections, some of which may occur during pregnancy. We explored these 2 hypotheses by assessing maternal infection during pregnancy and maternal as well as paternal infection in general as predictors of schizophrenia in their offspring. We found a slightly increased risk to be associated with prenatal infection exposure. However, the effect of prenatal infection exposure was not statistically significantly different from the effect of infection exposure in general. Parental infection appeared to be associated with development of schizophrenia in adolescence and early adulthood. Our study does not exclude a specific effect of infection during fetal life; yet, it does suggest that schizophrenia is associated with an increased familial liability to develop severe infection.

Offending prior to first psychiatric contact: a population-based register study

BACKGROUND

There is a well-established association between psychotic disorders and subsequent offending but the extent to which those who develop psychosis might have a prior history of offending is less clear. Little is known about whether the association between illness and offending exists in non-psychotic disorders. The aim of this study was to determine whether the association between mental disorder and offending is present prior to illness onset in psychotic and non-psychotic disorders.

METHOD

In a nested case-control study, cases (n=101,890) with a first psychiatric contact during the period 1995 to 2006 were identified and matched by age and gender to population-based controls (n=2,236,195). Exposure was defined as prior criminal and violent offending.

RESULTS

Males with one offence had an incidence rate ratio (IRR) of 2.32 [95% confidence interval (CI) 2.26-2.40] for psychiatric admission whereas two or more convictions yielded an IRR of 4.97 (95% CI 4.83-5.11). For violent offending the associations were stronger and IRRs of 3.97 (95% CI 3.81-4.12) and 6.18 (95% CI 5.85-6.52) were found for one and several offences respectively. Estimates for females were of a similar magnitude. The pattern was consistent across most diagnostic subgroups, although some variability in effect sizes was seen, and persisted after adjustment for substance misuse and socio-economic status (SES).

CONCLUSIONS

A prior history of offending is present in almost one in five patients presenting to mental health services, which makes it an important issue for clinicians to consider when assessing current and future risks and vulnerabilities.

Autoimmune diseases and severe infections as risk factors for schizophrenia: a 30-year population-based register study

OBJECTIVE

Autoimmune diseases have been associated with an increased risk of schizophrenia. It has been suggested that brain-reactive autoantibodies are part of the mechanisms behind this association. Furthermore, an increased permeability of the blood-brain barrier has been observed during periods of infection and inflammation. The authors therefore investigated whether autoimmune diseases combined with exposures to severe infections may increase the risk of schizophrenia

METHOD

Nationwide population-based registers in Denmark were linked, and the data were analyzed in a cohort study using survival analysis. All analyses were adjusted for calendar year, age, and sex. Incidence rate ratios and accompanying 95% confidence intervals (CIs) as measures of relative risk were used.

RESULTS

A prior autoimmune disease increased the risk of schizophrenia by 29% (incidence rate ratio=1.29; 95% CI=1.18-1.41). Any history of hospitalization with infection increased the risk of schizophrenia by 60% (incidence rate ratio=1.60; 95% CI=1.56-1.64). When the two risk factors were combined, the risk of schizophrenia was increased even further (incidence rate ratio=2.25; 95% CI=2.04-2.46). The risk of schizophrenia was increased in a dose-response relationship, where three or more infections and an autoimmune disease were associated with an incidence rate ratio of 3.40 (95% CI=2.91-3.94). The results remained significant after adjusting for substance use disorders and family history of psychiatric disorders. Hospital contact with infection occurred in nearly 24% of individuals prior to a schizophrenia diagnosis.

CONCLUSIONS

Autoimmune disease and the number of infections requiring hospitalization are risk factors for schizophrenia. The increased risk is compatible with an immunological hypothesis in subgroups of schizophrenia patients.

Association between prepartum maternal iron deficiency and offspring risk of schizophrenia: population-based cohort study with linkage of Danish national registers

Recent findings suggest that maternal iron deficiency may increase the risk of schizophrenia-spectrum disorder in offspring. We initiated this study to determine whether maternal prepartum anemia influences offspring risk of schizophrenia. We conducted a population-based study with individual record linkage of the Danish Civil Registration System, the Danish Psychiatric Central Register, and the Danish National Hospital Register. In a cohort of 1,115,752 Danish singleton births from 1978 to 1998, cohort members were considered as having a maternal history of anemia if the mother had received a diagnosis of anemia at any time during the pregnancy. Cohort members were followed from their 10th birthday until onset of schizophrenia, death, or December 31, 2008, whichever came first. Adjusted for relevant confounders, cohort members whose mothers had received a diagnosis of anemia during pregnancy had a 1.60-fold (95% confidence interval = 1.16-2.15) increased risk of schizophrenia. Although the underlying mechanisms are unknown and independent replication is needed, our findings suggest that maternal iron deficiency increases offspring risk of schizophrenia.

Autoimmune diseases, bipolar disorder, and non-affective psychosis

OBJECTIVE

Clinic-based studies of immune function, as well as comorbidity of autoimmune diseases, bipolar disorder, and schizophrenia, suggest a possible autoimmune etiology. Studies of non-affective psychosis and schizophrenia suggest common etiologies. The objective was to determine the degree to which 30 different autoimmune diseases are antecedent risk factors for bipolar disorder, schizophrenia, and non-affective psychosis.

METHODS

A cohort of 3.57 million births in Denmark was linked to the Psychiatric Case Register and the National Hospital Register. There were 20,317 cases of schizophrenia, 39,076 cases of non-affective psychosis, and 9,920 cases of bipolar disorder.

RESULTS

As in prior studies, there was a range of autoimmune diseases which predicted raised risk of schizophrenia in individuals who had a history of autoimmune diseases, and also raised risk in persons whose first-degree relatives had an onset of autoimmune disease prior to onset of schizophrenia in the case. These relationships also existed for the broader category of non-affective psychosis. Only pernicious anemia in the family was associated with raised risk for bipolar disorder (relative risk: 1.7), suggesting a small role for genetic linkage. A history of Guillain-Barré syndrome, Crohn's disease, and autoimmune hepatitis in the individual was associated with raised risk of bipolar disorder.

CONCLUSIONS

The familial relationship of schizophrenia to a range of autoimmune diseases extends to non-affective psychosis, but not to bipolar disorder. The data suggest that autoimmune processes precede onset of schizophrenia, but also non-affective psychosis and bipolar disorder.

Smoking and alcohol intervention before surgery: evidence for best practice

Smoking and hazardous drinking are common and important risk factors for an increased rate of complications after surgery. The underlying pathophysiological mechanisms include organic dysfunctions that can recover with abstinence. Abstinence starting 3-8 weeks before surgery will significantly reduce the incidence of several serious postoperative complications, such as wound and cardiopulmonary complications and infections. However, this intervention must be intensive to obtain sufficient effect on surgical complications. All patients presenting for surgery should be questioned regarding smoking and hazardous drinking, and interventions appropriate for the surgical setting applied.

Prediction of post-operative pain by an electrical pain stimulus

BACKGROUND

Treatment of post-operative pain is still a significant problem. Recently, interest has focused on pre-operative identification of patients who may experience severe post-operative pain in order to offer a more aggressive analgesic treatment. The nociceptive stimulation methods have included heat injury and pressure algometry. A simple method, Pain Matcher (PM), using electrical stimulation, is validated for pain assessment, but has not been evaluated as a tool for prediction of post-operative pain. Our aim was to assess the predictive value of pre-caesarean section pain threshold on intensity of post-caesarean section pain using the PM.

PATIENTS AND METHODS

Thirty-nine healthy women scheduled for elective caesarean section were studied. The anaesthetic/analgesic procedures included spinal anaesthesia, paracetamol, diclofenac, controlled-release (CR) oxycodone and morphine on request. Pre-operatively, the sensory and pain thresholds were measured using the PM. Post-operatively, a midwife, blinded for pre-caesarean pain threshold assessments, assessed the pain at rest and during mobilization every 12 h for 2 days. Consumption of analgesics was also recorded.

RESULTS

Pre-operative pain threshold correlated significantly with post-caesarean pain score (VAS) at rest and mobilization: [Spearman's rho =-0.65 (-0.30 to -0.75), P < 0.01] and [Spearman's rho =-0.52 (-0.23 to -0.72), P < 0.01], respectively. There was no significant correlation between pre-operative PM assessment of sensory threshold and post-operative pain.

CONCLUSION

Electrical pain threshold before caesarean section seems to predict the intensity of post-operative pain. This method may be used as a screening tool to identify patients at high risk of post-operative pain.

Breakthrough pain in opioid-treated chronic non-malignant pain patients referred to a multidisciplinary pain centre: a preliminary study

BACKGROUND

Breakthrough pain (BTP) has not formerly been discussed as such in chronic non-malignant pain patients referred to pain centres and clinics. The purpose of the study was to investigate the prevalence, characteristics and mechanisms of BTP in opioid-treated chronic non-malignant pain patients referred to a pain centre and to assess the short-term effects of pain treatment.

METHODS

Patients were assessed at referral (T(0)) and after a treatment period of 3 months (T(3)) using the visual analogue scale (VAS) of the brief pain inventory (BPI) within somatic nociceptive, neuropathic and/or visceral pain conditions, the mini mental state examination (MMSE) and the hospital anxiety and depression scale (HADS). The main treatment intervention from T(0) to T(3) was to convert short-acting oral opioids to long-acting oral opioids and to discontinue on demand and parenteral use of opioids.

RESULTS

Thirty-three patients were assessed at T(0) and 27 at T(3). The prevalence of BTP declined significantly from T(0) (90%) to T(3) (70.4%). Worst, least, average and current pain intensities as well as duration of BTP were significantly reduced from T(0) to T(3.) The majority of BTPs were exacerbation of background pain assumed to be of the same pain mechanisms. High average pain intensity (BPI) was significantly associated with high scores for both anxiety and depression (HADS).

CONCLUSION

BTP in chronic non-malignant pain patients seems to be surprisingly frequent and severe. Stabilizing the opioid regimen seems to reduce pain intensity in general as well as the intensity and duration of BTP. Average pain intensity was associated with anxiety and depression.

Lactogenic antibody responses in cows vaccinated with recombinant bovine rotavirus-like particles (VLPs) of two serotypes or inactivated bovine rotavirus vaccines

Triple-layered virus-like particles (VLPs) were produced in a baculovirus expression system from the two prevalent bovine rotavirus (BRV) serotypes, IND (P[5]G6) and 2292B (P[11]G10). Five groups of pregnant cows were inoculated intramuscularly and intramammarily with IND VLPs [BRV RF VP2, and IND VP4, 6, and 7, 250 microg per dose], 2292B VLPs [RF VP2, Cr VP4 (P[11]), and 2292B VP6 and 7, 250 microg per dose], combined IND/2292B VLPs (125 microg each VLP per dose), inactivated IND BRV (5x10(7)PFU per dose, pre-inactivation), or cell supernatant (mock-controls) in incomplete Freund's adjuvant. Serum, colostrum and milk were collected and tested for isotype-specific antibodies, and homologous and heterologous neutralizing antibodies (VN) to BRV by ELISA and VN tests, respectively. After vaccination, the IgG1 and homologous VN geometric mean antibody titers (GMTs) to BRV in serum of vaccinated groups were significantly (P<0.05) higher than in the mock-controls through postpartum day (PPD) 30. In colostrum, the IgG1 and IgA, and the homologous and heterologous VN GMTs of the IND VLP, 2292B VLP, combined IND/2292B VLP and the inactivated IND groups were significantly enhanced compared to the mock-controls, except for the heterologous VN GMTs in the inactivated IND group. However, the VLP vaccine groups had significantly higher homologous and heterologous VN GMTs than the inactivated IND group. The VN GMTs of the IND/2292B VLP group were statistically similar to the homologous VN GMTs of the IND or 2292B VLP groups, although the IgG1 GMT was lower. In milk, the IgG1 and homologous VN GMTs of the VLP groups were significantly higher than the inactivated IND or the mock-control groups through PPD30. However, the heterologous and homologous VN GMTs of inactivated IND group were statistically similar to the mock-control group at PPD0 and 30, respectively. These results demonstrate that the BRV antibody titers in serum, colostrum and milk are significantly enhanced by the use of triple-layered VLPs and inactivated IND vaccines, but significantly higher antibody responses were observed in the VLP vaccinated cows. The combined IND/2292B VLP vaccine induced comparable VN responses to BRV in serum, colostrum and milk compared to those induced by the individual IND or 2292B VLP vaccines, suggesting that at least two different serotypes can be mixed to confer maximum antibody responses to the incorporated serotypes.

Cross-protection studies between respiratory and calf diarrhea and winter dysentery coronavirus strains in calves and RT-PCR and nested PCR for their detection

A 1-step RT-PCR assay, targeting a 730 bp fragment of the nucleocapsid (N) gene of bovine coronavirus (BCV), and a nested PCR assay, targeting a 407 bp fragment of the N gene, were developed to detect BCV in nasal swab and fecal samples of calves experimentally exposed to BCV. Both 1-step RT-PCR and nested PCR recognized cell culture passaged isolates of 10 bovine respiratory coronavirus (BRCV), 5 calf diarrhea (CD) and 8 winter dysentery (WD) strains of BCV, but not transmissible gastroenteritis coronavirus or bovine rotavirus. The sensitivity of the 1-step RT-PCR and nested PCR was compared to that of an antigen-capture ELISA. The lowest detection limit of the 1-step RT-PCR and nested PCR as determined by using tenfold serial dilutions of the BRCV 255 and 440 strains in BCV negative nasal swab suspensions from preexposure gnotobiotic calves was 2 x 10(4) and 2 x 10(2) TCID50/0.1 ml for each strain, respectively. The lowest detection limit of the antigen-capture ELISA as determined by using the same serially diluted samples was 1 x 10(6) TCID50/0.1 ml for each strain. Therefore, the 1-step RT-PCR and nested PCR assays were 50 and 5000 times, respectively more sensitive than the antigen-capture ELISA to detect BRCV in nasal swab suspensions. To investigate in vivo cross-protection between the BRCV and CD or WD strains of BCV and to detect nasal and fecal shedding of BCV using the 1-step RT-PCR, nested PCR and antigen-capture ELISA, 6 colostrum-deprived and two gnotobiotic calves were inoculated with a BRCV, a CD or a WD strain of BCV and then challenged 3-4 weeks later with either BRCV, CD or WD strains of BCV. All calves developed diarrhea after inoculation and BCV antigen (ELISA) or RNA (RT-PCR) was detected in the diarrheic fecal samples or the corresponding nasal swab samples. In addition, low amounts of BCV were also detected only by nested PCR in the fecal and nasal swab samples before and after diarrhea. No respiratory clinical signs were observed during the entire experimental period, but elevated rectal temperatures were detected during diarrhea in the BCV-inoculated calves. All calves recovered from infection with the BRCV, CD, or WD strains of BCV were protected from BCV-associated diarrhea after challenge exposure with either a heterologous or homologous strain of BCV. However, all calves challenged with heterologous BCV strains showed subclinical BCV infection evident by detection of nasal and fecal shedding of BCV RNA detected only by nested PCR. Such results confirm field and experimental data documenting reinfection of the respiratory and enteric tracts of cattle, suggesting that, in closed herds, respiratory or enteric tract reinfections may constitute a source of BCV transmissible to cows (WD) or neonatal or feedlot calves. In addition, the present 1-step RT-PCR and nested PCR assays were highly sensitive to detect BCV in nasal swab and fecal specimens. Therefore, these assays should be useful to diagnose BCV infections in calves and adult cows.

The structure of mouse HP1 suggests a unique mode of single peptide recognition by the shadow chromo domain dimer

The heterochromatin protein 1 (HP1) family of proteins is involved in gene silencing via the formation of heterochromatic structures. They are composed of two related domains: an N-terminal chromo domain and a C-terminal shadow chromo domain. Present results suggest that chromo domains may function as protein interaction motifs, bringing together different proteins in multi-protein complexes and locating them in heterochromatin. We have previously determined the structure of the chromo domain from the mouse HP1beta protein, MOD1. We show here that, in contrast to the chromo domain, the shadow chromo domain is a homodimer. The intact HP1beta protein is also dimeric, where the interaction is mediated by the shadow chromo domain, with the chromo domains moving independently of each other at the end of flexible linkers. Mapping studies, with fragments of the CAF1 and TIF1beta proteins, show that an intact, dimeric, shadow chromo domain structure is required for complex formation.

Dual infection of gnotobiotic calves with bovine strains of group A and porcine-like group C rotaviruses influences pathogenesis of the group C rotavirus

There is serological evidence that bovine group C rotaviruses exist in the United States, but there are no reports of their isolation. Ninety fecal samples from calves with diarrhea, 81 samples from adult cows with diarrhea (winter dysentery), and 20 fecal samples from healthy adult cows were tested for group C rotaviruses by polyacrylamide gel electrophoresis, immune electron microscopy, and reverse transcription-PCR (RT-PCR). Three samples from adult cow diarrhea cases were positive only by RT-PCR, and a group C rotavirus was isolated from a positive sample in monkey kidney (MA104) cells (WD534tc/C). Genetically and serologically, the WD534tc/C strain was more closely related to the Cowden porcine group C strain than to the Shintoku bovine strain. Because the original cow feces also contained a group A rotavirus (detected after passage in cell culture), we hypothesized that such dual-rotavirus infections might play a role in the pathogenesis and host adaptation of rotaviruses. Thus, we examined the pathogenesis of WD534tc/C alone or combined with virulent (IND/A) or attenuated (NCDV/A) bovine group A rotaviruses in gnotobiotic calves. WD534tc/C alone induced diarrhea without (or with limited) virus shedding in inoculated calves (n = 3). In contrast, all calves coinfected with WD534tc/C and IND/A (n = 2) developed diarrhea and shed both viruses, whereas calves coinfected with WD534tc/C and NCDV/A (n = 3) developed diarrhea but did not shed either virus. Infection with WD534tc/C or NCDV/A alone caused only mild villous atrophy (jejunum and/or ileum), whereas dual infection with both viruses induced lesions throughout the small intestine. Although IND/A alone caused villous atrophy, more-widespread small intestinal lesions occurred in calves coinfected with WD534tc/C and IND/A. In conclusion, coinfection of calves with group A rotaviruses enhanced fecal shedding of a bovine group C rotavirus and the extent of histopathological lesions in the small intestines. Thus, our findings suggest a potential novel hypothesis involving dual infections for the adaptation of heterologous rotaviruses to new host species.

Comparison of transarterial and multiple nerve stimulation techniques for axillary block using a high dose of mepivacaine with adrenaline

BACKGROUND

High-dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer's recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double-blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques.

METHODS

Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow.

RESULTS

The MNS group required median 11 min for block performance compared with 8 min for the TA group (P < 0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P < 0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P < 0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P < 0.001.

CONCLUSION

The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions.

Further validation of antibody-capture and antigen-capture enzyme-linked immunosorbent assays for determining exposure of cattle to bovine coronavirus

OBJECTIVE

To further validate an antibody-capture ELISA for measuring bovine coronavirus (BCV) exposure (antibody seroresponse) in cattle and to explain the apparent loss of sensitivity of a BCV antigen-capture ELISA when testing feces from adult versus neonatal cattle.

ANIMALS

98 adult cows from herds with and without winter dysentery; 10 gnotobiotic or colostrum-deprived calves.

PROCEDURES

Results of an antibody-capture ELISA for BCV and a plaque reduction virus neutralization assay performed on paired serum samples from 24 cattle were compared with each other and with results of immunoelectron microscopy (IEM) of feces for BCV. For samples from 98 cattle, results of antibody-capture ELISA were compared with results of IEM. Calves were inoculated with feces ELISA-positive or IEM-positive for BCV and monitored for BCV infection. An ELISA was developed to detect BCV antigen-antibody complexes in feces and results were compared with results of an antigen-capture ELISA and IEM.

RESULTS

Antibody-capture ELISA results correlated with neutralization assay results, but agreed more closely with results of IEM. Calves became infected with BCV following inoculation with either ELISA-positive or ELISA-negative but IEM-positive feces. Results of the antigen-antibody ELISA correlated with results of IEM and the antigen-capture ELISA.

CLINICAL IMPLICATIONS

In adult cattle, testing of paired serum samples by use of an antibody-capture ELISA may be a better indicator of recent BCV exposure than results of virus neutralization tests. Antigen-antibody binding in feces may interfere with results of antigen-capture ELISA for BCV.

Age dependency of resistance to cerebrospinal fluid outflow

OBJECT

Resistance to cerebrospinal fluid (CSF) outflow (Rout)is an important parameter in assessing the need for CSF shunt placement in patients with hydrocephalus. The normal lower limit of Rout has been estimated on the basis of the clinical effect of shunt placement in patients with varying values of Rout and in young healthy volunteers. The lack of clinical effect from CSF shunts in some elderly patients, despite elevated Rout,suggests that the normal value of Rout increases with age and may be higher in elderly persons. The aim of the present study was to examine the relationship between Rout and age in patients without known CSF dynamic disturbances.

METHOD

Fifty-two patients ranging from 20 to 88 years of age and with no known CSF dynamic disorders were examined. The Rout was measured using a lumbar computerized infusion test. The correlation between Rout and age was analyzed by performing linear regression. The Rout increased significantly with patient age. The Rout in a patient in the eighth decade will be approximately 5 mm Hg/ml/minute higher than in a young patient.

CONCLUSIONS

The present study shows a small but critical increase in Rout with increased patient age. A notable residual variation was present and borderline values of Rout should be regarded and used with caution.

Passive immunity to bovine rotavirus in newborn calves fed colostrum supplements from cows immunized with recombinant SA11 rotavirus core-like particle (CLP) or virus-like particle (VLP) vaccines

Heterotypic passive immunity to IND (P/5/G6) bovine rotavirus (BRV) was evaluated. Three groups of calves (n = 5 per group) were fed 1% pooled colostrum supplements (birth to 7 days of age) from BRV seropositive cows vaccinated with recombinant SA11(P/2/G3) rotavirus-like particles (VLPs), recombinant SA11 rotavirus core-like particles (CLPs), or inactivated SA11 rotavirus (SA11). Control calves (n = 5 per group) received either pooled colostrum from unvaccinated (BRV field exposure seropositive) control cows, or no colostrum. IgG1 antibody titers to IND BRV for the pooled colostrum were: 1,048,576 (VLP); 1,048,576 (CLP); 262,144 (SA11); and 16,384 (control colostrum). Elevated titers of BRV neutralizing (VN) antibodies were present in VLP colostrum (98,000), and SA11 colostrum (25,000), but not in CLP colostrum (1400), compared to colostrum from nonvaccinates (2081). Calves were orally inoculated with virulent IND BRV at 2 days of age and challenged at post-inoculation day (PID) 21. Calves were monitored daily for diarrhea and faecal BRV shedding through PID 10 and post-challenge day (PCD) 10. After colostrum feeding, the IgG1 antibody titers were highest in serum and faeces of calves fed VLP and CLP colostrum, but VN and IgA antibodies were highest in calves fed VLP colostrum. After BRV inoculation, calves fed colostrum from vaccinated cows had significantly fewer days of BRV-associated diarrhea and BRV shedding than control calves. All calves fed VLP colostrum were protected from diarrhea after BRV inoculation; two calves shed BRV. In the CLP colostrum group, one calf developed BRV-associated diarrhea and all calves shed virus. In the SA11 colostrum group, three calves developed BRV-associated diarrhea and four calves shed virus. BRV-associated diarrhea and shedding occurred in 9 of 10 control calves. Active IgM antibody responses occurred in faeces and/or serum of most calves after BRV inoculation. However, the highest active antibody responses (IgM and IgG1 in serum, and IgM, IgG1 or IgA in faeces) after BRV inoculation were in calves fed control or no colostrum, in association with clinical diarrhea in most of these calves. After challenge at PID 21, BRV-associated diarrhea and shedding were of short duration or absent, in all groups. These results demonstrate the efficacy of colostrum from VLP vaccinated cows to provide heterologous, passive protection against BRV diarrhea and shedding in calves. In comparison, calves fed CLP or SA11 colostrum were only partially protected against BRV diarrhea or shedding.

The solution structure of the N-terminal domain of alpha2-macroglobulin receptor-associated protein

The three-dimensional structure of the N-terminal domain (residues 18-112) of alpha2-macroglobulin receptor-associated protein (RAP) has been determined by NMR spectroscopy. The structure consists of three helices composed of residues 23-34, 39-65, and 73-88. The three helices are arranged in an up-down-up antiparallel topology. The C-terminal 20 residues were shown not to be in a well defined conformation. A structural model for the binding of RAP to the family of low-density lipoprotein receptors is proposed. It defines a role in binding for both the unordered C terminus and the structural scaffold of the core structure. Pathogenic epitopes for the rat disease Heymann nephritis, an experimental model of human membranous glomerulonephritis, have been identified in RAP and in the large endocytic receptor gp330/megalin. Here we provide the three-dimensional structure of the pathogenic epitope in RAP. The amino acid residues known to form the epitope are in a helix-loop-helix conformation, and from the structure it is possible to rationalize the published results obtained from studies of fragments of the N-terminal domain.

Dissection of the domain architecture of the alpha2macroglobulin-receptor-associated protein

The alpha2macroglobulin-receptor-associated protein (RAP) binds to the alpha2macroglobulin receptor/low-density lipoprotein receptor-related protein (alpha2MR/LRP), a multi-functional cell surface receptor known to bind and internalize several macromolecular ligands. RAP has been shown to inhibit binding of all known alpha2MR/LRP ligands. Mutational studies have implicated distinct parts of RAP as specifically involved in inhibition of binding of a multitude of ligands. In the present paper we provide experimental evidence allowing assignment of elements of triplicate internal sequence similarity in RAP, noted previously [Warshawsky, I., Bu, G. & Schwartz, A. L. (1995) Sites within the 39-kDa protein important for regulating ligand binding to the low-density lipoprotein receptor-related protein, Biochemistry 34, 3404-3415], to three structural domains, 1, 2 and 3, comprising residues 18-112, 113-218 and 219-323 of RAP, respectively. Structural analysis by 1H-NMR spectroscopy shows that domains 1 and 2 as separate domains have similar secondary structures, consisting almost exclusively of alpha-helices, whereas domain 3 as a separate domain appears only to be marginally stable. Ligand competition titration of recombinant RAP domains 1, 2 and 3 and double domains 1+2 and 2+3 against 125I-RAP and 125I-alpha2M* (methylamine-activated alpha2M) for binding to alpha2MR/LRP demonstrated (a) that functional integrity in single domains is largely preserved, and (b) that important determinants for the inhibition of test ligands reside in the C-terminal regions of domains 1 and 3.

Analgesic effect of intraarticular morphine. A controlled, randomised and double-blind study

BACKGROUND

Opioids produce antinociceptive effect by acting on receptors on peripheral nerves. The clinical relevance of this effect is still debated. The aim of the study was to compare the analgesic effect of morphine intraarticularly with the intramuscular route of administration after knee surgery.

METHODS

Sixty-one patients, ASA 1-2, having elective arthroscopic surgery of the knee were randomised to either an intraarticular or intramuscular dose of morphine 5 mg. The pain sensation was estimated by visual analogue scale and a verbal rating score 0, 1, 2 and 4 hours postoperatively and verbal rating score on the third day. The use of acetaminophen and supplementary opioids were recorded for the first 4 hours postoperatively, from 4 hours until the third day, and from day 3 to day 7 postoperatively.

RESULTS

The groups were comparable. Three patients were excluded. There were no statistically significant differences in painscore and consumption of analgesics. Fifty-nine per cent in each group had macroscopic synovitis. In the intraarticular group, there was no increased effect of morphine in the patients with synovitis compared to patients without synovitis.

CONCLUSIONS

The clinical analgesic effect of 5 mg morphine given intraarticularly is equal to 5 mg morphine given intramuscularly. The occurrence of villous synovitis seems to be of no clinical importance concerning the local effect of morphine.

Management of postoperative pain. An intervention study

BACKGROUND

In 1989 a study had shown that the quality of postoperative pain treatment (PPT) in a district general hospital was not satisfactory. Therefore, new instructions for PPT were issued, intra-venous medication with morphine was introduced on the wards, and the staff was educated in PPT. The purpose of this study was to investigate the quality of PPT in 1992 compared to the quality in 1989.

METHODS

Using identical questionnaires, 191 patients in 1989 and 126 patients in 1992 were interviewed before and 2-5 days after surgery regarding postoperative pain. At the postoperative interview patients in pain also filled out the McGill Pain Questionnaire. A questionnaire was also answered by the nurses regarding PPT in 1989 and in 1992.

RESULTS

1992 compared to 1989 (1992/1989): all patients were now medicated (100%/93%), most of them regularly (79%/ 4%) and the majority (94%/15%) also received non-opioid analgesic. Fewer patients (65%/80%) experienced postoperative pain lasting more than one day following surgery. Analgesic prescription was more standardized. In 1992 the nurses were more satisfied than in 1989 with the PPT and the physicians' prescribing patterns. All the above-mentioned parameters were significantly improved from 1989 to 1992. All the different pain-scores showed a reduction (8-30%) but did not reach statistical significance (P = 0.2).

CONCLUSIONS

Our two investigations show that it is possible to improve the quality of pain management with rather simple reforms.

Structure in solution of a four-helix lipid binding protein

Because of the low solubility of lipids in water, intercellular and intracellular pathways of lipid transfer are necessary, e.g., for membrane formation. The mechanism by which lipids in vivo are transported from their site of biogenesis (endoplasmatic reticulum and the chloroplasts) to their place of action is unknown. Several small plant proteins with the ability to mediate transfer of radiolabeled phospholipids in vitro from liposomal donor membranes to mitochondrial and chloroplast acceptor membranes have been isolated, and a protein with this ability, the nonspecific lipid transfer protein (nsLTP) isolated from barley seeds (bLTP), has been studied here. The structure and the protein lipid interactions of lipid transfer proteins are relevant for the understanding of their function, and here we present the three-dimensional structure in solution of bLTP as determined by NMR spectroscopy. The 1H NMR spectrum of the 91-residue protein was assigned for more than 97% of the protein 1H atoms, and the structure was calculated on the basis of 813 distance restraints from 1H-1H nuclear Overhauser effects, four disulfide bond restraints, from dihedral angle restraints for 66 phi-angles, 61 chi 1 angles, and 2 chi 2 angles, and from 31 sets of hydrogen bond restraints. The solution structure of bLTP consists of four well-defined alpha-helices A-D (A, Cys 3-Gly 19; B, Gly 25-Ala 38; C, Arg 44-Gly 57; D, Leu 63-Cys 73), separated by three short loops that are less well defined and concluded by a well defined C-terminal peptide segment with no observable regular secondary structure. For the 17 structures that are used to represent the solution structure of bLTP, the RMS deviation to an average structure is 0.63 A +/- 0.04 A for backbone atoms and 0.93 A +/- 0.06 A for all heavy atoms. The secondary structure elements and their locations in the sequence resemble those of nsLTP from two other plant species, wheat and maize, whose structures were previously determined (Gincel E et al, 1995, Eur J Biochem 226:413-422; Shin DH et al, 1995, Structure 3:189-199). In bLTP, the residues analogous to those in maize nsLTP that constitute the palmitate binding site are forming a similar hydrophobic cavity and a potential acyl group binding site. Analysis of the solution structure of bLTP and bLTP in complex with a ligand might provide information on the conformational changes in the protein upon ligand binding and subsequently provide information on the mode of ligand uptake and release. In this work, we hope to establish a foundation for further work of determining the solution structure of bLTP in complex with palmitoyl coenzyme A, which is a suitable ligand, and subsequently to outline the mode of ligand binding.

Effect of arm position on the effectiveness of perivascular axillary nerve block

The influence of arm position on the effectiveness of perivascular axillary nerve block with a catheter was assessed prospectively in two groups of patients. Ninety patients were allocated randomly to receive 1% mepivacaine with adrenaline 40 ml with the arm either adducted or abducted. Radiographs were taken in 12 additional patients; six in each group immediately after injection of 2% mepivacaine 20 ml mixed with contrast agent 20 ml. There were no statistically significant differences in onset time, spread of analgesia, motor block or success rate between the two groups. Proximal flow of the local anaesthetic-contrast agent mixture was neither facilitated by arm adduction nor was it necessary for the development of a successful block.

Protein-ligand interactions in the lysine-binding site of plasminogen kringle 4 are different in crystal and solution. Electrostatic interactions studied by site-directed mutagenesis exclude Lys35 as an important acceptor in solution

Three amino acid residues previously reported to establish the interactions between lysine-like derivatives and plasminogen kringle 4 have been replaced by other residue types using the methods of site-directed mutagenesis. The effect of these modifications on the binding constant have been measured. The residues are Lys35, Asp57, and Arg71, according to the sequence numbering scheme adapted from the plasminogen kringle 5 domain. The plasminogen kringle 4 derivatives where Lys35 of the native molecule is replaced with isoleucine and methionine residues, respectively, were seen to bind the ligands, respectively, with association constants similar to those of the unmodified recombinant kringle 4 domain. The modification of Asp57 to asparagine was shown to eliminate the ability to bind to the lysine affinity column used to purify the protein. Similarly the site-directed mutagenesis for Arg71 to glutamine resulted in a 12-19-fold decrease in binding of each of the two ligands. In addition, the effect of ionic strength on the binding of 6-aminohexanoic acid to the recombinant plasminogen kringle 4 and the three single substituted derivatives was examined. For the unmodified kringle domain as well as for the two derivatives modified only at the position of Lys35, an ionic strength of 0.5 M reduced the binding constant by a factor of 3 to 0.12 x 10(5) M-1. The derivative modified at the position of Arg71 was not effected by the ionic strength and maintained a rather low binding constant of 0.02 x 10(5) M-1. The observations suggest that the carboxylate of Asp57 and the guanidino group of Arg71 provide the electrostatic interaction in the binding site for the epsilon-amino group and the alpha-carboxylate of a C-terminal lysine residue.(ABSTRACT TRUNCATED AT 250 WORDS)

[Treatment of hip fractures in a department of general surgery and a department of orthopedic surgery. A comparison]

All patients treated for fractures of the hip in 1989 in a department of general surgery and a department of orthopedics were included in this study. Data regarding demographics, length of hospitalization, rehabilitation, postoperative complications, types of fractures and modes of operation were retrospectively registered and compared. Mean length of hospitalization was significantly longer and the incidence of postoperative complications was significantly higher in the department of general surgery when compared to the specialized department of orthopedics especially with regard to wound infections and the formation of bedsores. We tentatively propose reasons for these differences.