Kinematic gait characteristics of straight line walk in clinically sound dairy cows.

The aim of this study is to describe the kinematic gait characteristics of straight line walk in clinically sound dairy cows using body mounted Inertial Measurement Units (IMUs) at multiple anatomical locations. The temporal parameters used are speed and non-speed normalized stance duration, bipedal and tripedal support durations, maximal protraction and retraction angles of the distal limbs and vertical displacement curves of the upper body. Gait analysis was performed by letting 17 dairy cows walk in a straight line at their own chosen pace while equipped with IMU sensors on tubera sacrale, left and right tuber coxae (LTC and RTC), back, withers, head, neck and all four lower limbs. Data intervals with stride by stride regularity were selected based on video data. For temporal parameters, the median was calculated and 95% confidence intervals (CI) were estimated based on linear mixed model (LMM) analysis, while for limb and vertical displacement curves, the median and most typical curves were calculated. The temporal parameters and distal limb angles showed consistent results with low variance and LMM analysis showed non-overlapping CI for all temporal parameters. The distal limb angle curves showed a larger and steeper retraction angle range for the distal front limbs compared with the hind limbs. The vertical displacement curves of the sacrum, withers, LTC and RTC showed a consistent sinusoidal pattern while the head, back and collar curves were less consistent and showed more variation between and within cows. This kinematic description might allow to objectively differentiate between normal and lame gait in the future and determine the best anatomical location for sensor attachment for lameness detection purposes.

Correction to: Inflammatory markers before and after farrowing in healthy sows and in sows affected with postpartum dysgalactia syndrome.

The original article [1] contains an error whereby the caption in Figure 8 is incorrect; the correct caption can be seen ahead alongside its respective image.

Lecocytes mutation load declines with age in carriers of the m.3243A>G mutation: A 10-year Prospective Cohort.

Carriers of the mitochondrial mutation m.3243A>G presents highly variable phenotypes including mitochondrial encephalomyopathy, lactoacidosis and stroke-like episodes (MELAS). We conducted a follow-up study to evaluate changes in leucocyte heteroplasmy and the clinical phenotypes in m.3243A>G carriers. Leucocyte heteroplasmy was determined by next generation sequencing covered by 100 000X reads in 32 individuals with a median follow-up of 10.2 years. Ten-year clinical follow-up is reported in 46 individuals. The annual leucocyte mutation level declined by -0.7 (±0.4) percentage points/year (P < .0001), and correlated with the level of the initial sample (ρ = -0.92, P < .0001). Eleven of 46 m.3243A>G carriers died and clinical symptoms progressed. This longitudinal study shows the decline in leucocyte m.3243A>G heteroplasmy associates with the level of the initial sample. Further, there was a high mortality among carriers.

Impact of contact investigation and tuberculosis screening among high-risk groups in Denmark.

SETTING: The objective of tuberculosis (TB) screening in low-incidence countries is to identify TB patients earlier, ideally to improve health outcomes and reduce Mycobacterium tuberculosis transmission. In this retrospective study, we compare hospitalisation (morbidity) and smear positivity rates (infectiousness) in TB patients identified through active case finding (ACF) with patients identified through passive case finding (PCF). METHODS: ACF patients were identified by screening socially marginalised persons or through contact investigation. Logistic regression was used to model the associations between case-finding group (ACF/PCF) and hospitalisation, and between case-finding group and smear positivity rates. RESULTS: A total of 108 patients were identified through ACF and 332 through PCF. Thirty (27.8%) ACF patients and 153 (46.1%) PCF patients were hospitalised. In the adjusted models, ACF patients (OR 0.24, P 0.001) and ACF subgroups identified using mobile X-ray screening, spot sputum culture screening and contact investigation were significantly less likely to be hospitalised than PCF patients. Thirty-one (34.4%) ACF patients and 127 (50.4%) PCF patients were smear-positive. ACF patients (OR 0.30, P 0.001) and ACF subgroups identified through contact investigation and spot sputum culture screening were less likely to be smear-positive than PCF patients. CONCLUSIONS: These findings suggest that ACF reduces morbidity and infectiousness among TB patients, thereby potentially improving health outcomes and reducing transmission of M. tuberculosis.

Diabetes-related tuberculosis in Denmark: effect of ethnicity, diabetes duration and year of diagnosis.

BACKGROUND: The association between diabetes mellitus (DM) and tuberculosis (TB) has been established on the basis of cross-sectional studies; however, only a few longitudinal studies have been conducted, with inconsistent results. OBJECTIVE: To study the effect of ethnicity and the presence and duration of DM on the risk of incident TB based on 15 years of follow-up of the entire Danish population. DESIGN AND METHODS: Using Poisson regression analysis, we estimated TB incidence in individuals with DM vs. those without DM by linking nationwide DM and TB registers to the National Civil Register at case level. RESULTS: The TB rate ratio was 1.9 in individuals with DM compared to non-DM individuals, regardless of country of birth, with the exception of African-born individuals (rate ratio 0.5). The risk decreased drastically within the first 2 years after the diagnosis of DM; no association was found with longer durations of DM. The risk also decreased the later the year of DM diagnosis. CONCLUSIONS: The study confirmed DM as a risk factor for TB, except in the case of African-born individuals. Other non-DM risk factors for TB could act as effect-modifiers on the DM-TB association. Implementing earlier DM diagnosis and improving metabolic control may reduce the risk of DM-related TB.

Pre-test habituation improves the reliability of a handheld test of mechanical nociceptive threshold in dairy cows.

Mechanical nociceptive threshold (MNT) testing has been used to investigate aspects of painful states in bovine claws. We investigated a handheld tool, where the applied stimulation force was monitored continuously relative to a pre-encoded based target force. The effect on MNT of two pre-testing habituation procedures was performed in two different experiments comprising a total of 88 sound Holsteins dairy cows kept either inside or outside their home environment. MNT testing was performed using five consecutive mechanical nociceptive stimulations per cow per test at a fixed pre-encoded target rate of 2.1N/s. The habituation procedure performed in dairy cows kept in their home environment led to lowered intra-individual coefficient of variation of MNT (P<0.001), increased MNT (P<0.001) and decreased the discrepancy between applied and target force during stimulations (P<0.001). Pre-test habituation improved the reliability of the handheld tool when used in dairy cows kept in their home environment.

Influence of disease process and duration on acute phase proteins in serum and peritoneal fluid of horses with colic.

BACKGROUND: The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and fibrinogen are valuable blood biomarkers in equine inflammatory diseases, but knowledge of factors influencing their concentrations in blood and peritoneal fluid (PF) of horses with colic is needed. OBJECTIVES: The objective of this study was to investigate the influence of demographics (age, sex, breed), disease process (simple obstruction, strangulating obstruction, inflammatory), disease location, disease duration, hypovolemia, and admission hospital on concentrations of APP, lactate and white blood cell counts (WBC) in horses with colic admitted to 2 referral hospitals. ANIMALS: The study included 367 horses with colic admitted at 2 referral hospitals. METHODS: Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associations between biomarker concentrations and clinical variables were analyzed using multivariate linear regression analysis. RESULTS: Increasing pre-admission duration of colic was associated with increased concentrations of APP in blood and PF. Blood concentrations of SAA and fibrinogen were associated with disease process (inflammatory, strangulations, simple obstructions) in more colic duration groups (5-12 and >24 hours) than any of the other biomarkers. No relevant associations between demographic factors, hospital, or hydration status and the measured biomarkers were found. CONCLUSIONS AND CLINICAL IMPORTANCE: In horses with colic, concentrations of APP are associated mainly with disease process and duration of colic and may thus be used for assessment of disease independently of demographic or geographic factors. Serum amyloid A may be a diagnostic marker for use in colic differential diagnosis, but further evaluation is needed.

Emergence of enterovirus 71 C4a in Denmark, 2009 to 2013.

Enterovirus (EV) 71 has emerged as a primary cause of severe neurologic enterovirus infection in the aftermath of the global polio eradication effort. Eleven subgenotypes of EV71 exist, the C4 subgenotype being associated with large outbreaks in Asia with high mortality rates. This subgenotype has rarely been reported in Europe. In the period between 1 January 2009 and 31 December 2013 a total of 1,447 EV positive samples from 1,143 individuals were sent to the Statens Serum Institute (SSI), and 938 samples from 913 patients were genotyped at the Danish National World Health Organization Reference laboratory for Poliovirus at SSI. Echovirus 6 (E06) (n=141 patients), echovirus 30 (E30) (n=114), coxsackievirus A6 (CA06) (n=96) and EV71 (n=63) were the most prevalent genotypes. We observed a shift in circulating EV71 subgenotypes during the study period, with subgenotype C4 dominating in 2012. A total of 34 EV71 patients were found to be infected with strains of the C4 subgenotype, and phylogenetic analysis revealed that they belonged to the C4a lineage. In our study, the proportions of cases with cerebral and/or sepsis-like symptoms were similar in those affected by C4a (19/34) and those with C1 and C2 (15/35). The majority (n=30) of the 34 EV71 C4 cases were children≤5 years of age, and males (n=22) were over-represented. Continued EV surveillance is required to monitor the spread of EV71 C4 in Denmark and the rest of Europe.

Rater agreement on gait assessment during neurologic examination of horses.

BACKGROUND: Reproducible and accurate recognition of presence and severity of ataxia in horses with neurologic disease is important when establishing a diagnosis, assessing response to treatment, and making recommendations that might influence rider safety or a decision for euthanasia. OBJECTIVES: To determine the reproducibility and validity of the gait assessment component in the neurologic examination of horses. ANIMALS: Twenty-five horses referred to the Royal Veterinary College Equine Referral Hospital for neurological assessment (n = 15), purchased (without a history of gait abnormalities) for an unrelated study (n = 5), or donated because of perceived ataxia (n = 5). METHODS: Utilizing a prospective study design; a group of board-certified medicine (n = 2) and surgery (n = 2) clinicians and residents (n = 2) assessed components of the equine neurologic examination (live and video recorded) and assigned individual and overall neurologic gait deficit grades (0-4). Inter-rater agreement and assessment-reassessment reliability were quantified using intraclass correlation coefficients (ICC). RESULTS: The ICCs of the selected components of the neurologic examination ranged from 0 to 0.69. "Backing up" and "recognition of mistakes over obstacle" were the only components with an ICC > 0.6. Assessment-reassessment agreement was poor to fair. The agreement on gait grading was good overall (ICC = 0.74), but poor for grades ≤ 1 (ICC = 0.08) and fair for ataxia grades ≥ 2 (ICC = 0.43). Clinicians with prior knowledge of a possible gait abnormality were more likely to assign a grade higher than the median grade. CONCLUSION AND CLINICAL IMPORTANCE: Clinicians should be aware of poor agreement even between skilled observers of equine gait abnormalities, especially when the clinical signs are subtle.

Technical note: Effects of frozen storage on the mechanical properties of the suspensory tissue in the bovine claw.

It is proposed that a softening of the suspensory tissue in the claw is involved in the development of lameness and claw lesions in cattle. A relatively small amount of research has been carried out to verify this theory. Research in this area would be simplified if mechanical testing of the suspensory tissue could be performed on frozen and stored specimens. The current study tested whether freezing of the specimens changes the suspensory tissues' mechanical properties. Limbs from 3 freshly slaughtered Danish Holstein dairy cows and 6 nonpregnant Angus heifers, without clinical signs of lameness, were allocated to 1 of 2 treatments (frozen or nonfrozen) in such a way that each cow was represented in each treatment group with a frozen limb and a corresponding nonfrozen limb (i.e., frozen left front, fresh right front, and so on). The frozen limbs were kept at -18°C for a week before processing and the nonfrozen limbs were processed within 2h of slaughter. Two samples measuring 8 × 8 mm were cut from the abaxial side of each claw in such a way that the sample included the horn of the abaxial wall, pedal bone, and the interposed corium. The samples were kept on ice until being mounted in a large deformation rheometer with an extension testing frame, fixed by the horn and the pedal bone, and loaded to failure. During deformation force and displacement data were recorded, from which corresponding stress and strain were calculated. Young's modulus (a measure of tissue elasticity or stiffness) and a measure of physiological support (PS; force needed to displace the sample 1mm) were calculated from the data. The response variables, Young's modulus and PS, were analyzed separately by a mixed model. The explanatory variables were treatment (frozen or nonfrozen), limb (front or back), claw (medial or lateral), position of the sample (dorsal or palmar-plantar), and group (Angus or Holstein). Interactions between group and treatment and between limb, claw, and sample position were included in the model. Cow identity was included as a random effect. Model reduction was performed by stepwise backward elimination, until all remaining terms were significant at the 5% level or less. Freezing had no effect on the elasticity of the suspensory apparatus or on PS. However, PS was affected by limb (hind legs had higher PS values than front) and the position of the sample (palmar-plantar samples had higher PS values than dorsal). The Angus group had higher PS values than the Holstein group, but the groups differed in age, parity, body weight, lactation, housing, and management, as well as in breed; therefore, further studies are needed to investigate these effects. The results indicate that mechanical testing of bovine claw suspensory tissue can be performed on specimens that have been frozen, thus aiding research in the mechanical aspect of bovine lameness and claw lesions.

HIV testing of patients diagnosed with tuberculosis increased in Denmark during the period from 2007 to 2009.

We examined the trends of HIV testing among patients notified with TB in Denmark during a 3-year period from 2007 to 2009. We were able to obtain HIV testing status for 96%. There was a significant increase of patients examined for HIV infection during the 3-year period. HIV prevalence among HIV-tested TB patients in Denmark is much higher than in the average population. It seems there is an increasing awareness in Denmark towards testing TB cases for HIV co-infection.

Clustered tuberculosis in a low-burden country: nationwide genotyping through 15 years.

Molecular genotyping of Mycobacterium tuberculosis has proved to be a powerful tool in tuberculosis surveillance, epidemiology, and control. Based on results obtained through 15 years of nationwide IS6110 restriction fragment length polymorphism (RFLP) genotyping of M. tuberculosis cases in Denmark, a country on the way toward tuberculosis elimination, we discuss M. tuberculosis transmission dynamics and point to areas for control interventions. Cases with 100% identical genotypes (RFLP patterns) were defined as clustered, and a cluster was defined as cases with an identical genotype. Of 4,601 included cases, corresponding to 76% of reported and 97% of culture-verified tuberculosis cases in the country, 56% were clustered, of which 69% were Danes. Generally, Danes were more often in large clusters (≥ 50 persons), older (mean age, 45 years), and male (male/female ratio, 2.5). Also, Danes had a higher cluster frequency within a 2-year observation window (60.8%), and higher clustering rate of new patterns over time, compared to immigrants. A dominant genotype, cluster 2, constituted 44% of all clustered and 35% of all genotyped cases. This cluster was primarily found among Danish males, 30 to 59 years of age, often socially marginalized, and with records of alcohol abuse. In Danes, cluster 2 alone was responsible for the high cluster frequency level. Immigrants had a higher incidence of clustered tuberculosis at a younger age (0 to 39 years). To achieve tuberculosis elimination in Denmark, high-risk transmission environments, like the cluster 2 environment in Danes, and specific transmission chains in immigrants in the capital area, e.g., homeless/socially marginalized Somalis/Greenlanders, often with alcohol abuse, must be targeted, including groups with a high risk of reactivation.

Sporting activity following colic surgery in horses: a retrospective study.

REASONS FOR PERFORMING STUDY: There is a paucity of studies addressing sporting activity and horse owners' satisfaction after horses have undergone colic surgery. OBJECTIVES: To determine 1) survival rate after colic surgery, 2) prevalence of horses returning to, or starting, sporting activities and 3) assess the owners' satisfaction regarding colic surgery. METHODS: Cases that underwent exploratory celiotomy for colic between January 2005 and August 2010 were reviewed. All horses that had one or more celiotomies and were discharged after colic surgery were included in a telephone questionnaire survey. Only horses that survived at least 6 months after colic surgery were included in the sporting activity analysis. Data extracted from the records included case details, intra-operative diagnosis and surgical treatment. Information from a telephone questionnaire included the horses' post surgical details (horse alive or subjected to euthanasia, post operative complications, pre- and post surgical use, return to sporting activity, sporting performance, behavioural changes, management changes and recommendation by owner for colic surgery). A logistic regression model was used for the statistical analysis of post hospitalisation performance and an ordinal regression model used for analysis of post colic complications and of owner's recommendation of surgery. A Kaplan-Meier survival curve was computed to show survival of horses discharged after colic surgery. RESULTS: The survival rates (%) at 6, 12, 24, 36, 48 and 60 months were 95.3, 86.6, 80.9, 76.9, 62.1 and 57.6, respectively. A large majority of horses (86.1%) resumed or started sporting activities after colic surgery. The proportion of horses that the owners believed to achieve the same or better performance after surgery was 83.5%. In 89.9% of the cases, owners stated that they would recommend colic surgery. CONCLUSIONS: Horses discharged after colic surgery had a high long-term survival rate. A high prevalence of horses resumed or started sporting activities with a high proportion of horses at their presurgical performance level. The large majority of owners of discharged horses were satisfied with colic surgery performed on their horses.

Nephrosplenic entrapment of the large colon in 142 horses (2000-2009): analysis of factors associated with decision of treatment and short-term survival.

REASONS FOR PERFORMING STUDY: Previous studies indicate similar overall survival of horses with nephrosplenic entrapment of the large colon (NSE), regardless of treatment strategy. Short-term survival of a primarily conservative treatment strategy without rolling under general anaesthesia (GA) and a low proportion of surgical intervention as well as indicators of short-term nonsurvival has not been documented. OBJECTIVES: To document short-term survival of horses with NSE treated in a university referral hospital with a low rate of surgical interventions and to determine factors associated with the decision of treatment and short-term nonsurvival. METHODS: A retrospective review of medical records of 142 horses diagnosed with NSE between January 2000 and October 2009 was undertaken. Case details and clinical parameters from the initial examination, treatment and outcome were recorded. Factors associated with decision of treatment and short-term survival were identified by multiple logistic regression analysis. RESULTS: Warmblood breeds were over-represented in comparison to the general colic population. Overall short-term survival was 91.5% (130/142) which is similar to previous studies. Three horses considered to be in need of surgery were subjected to euthanasia for economical reasons before treatment. Of 114 conservatively treated horses, 110 (96.5%) survived, as did 20/25 (80%) of surgically treated horses. Nine conservatively managed horses were treated with phenylephrine. Gastric reflux (P = 0.0077), pain (P = 0.024) and abdominal distension (P = 0.05) were associated with the decision to treat surgically. Increased heart rate (P<0.001), and surgery (P = 0.032) were associated with reduced likelihood of short-term survival. CONCLUSIONS AND POTENTIAL RELEVANCE: Overall short-term survival was similar to that reported in previous studies with higher proportions of surgically managed cases. Consequently, horses with NSE should be managed by a primarily conservative treatment strategy, with the decision to treat surgically based on specific evidence based criteria.

Electronic real-time surveillance for influenza-like illness: experience from the 2009 influenza A(H1N1) pandemic in Denmark.

To enhance surveillance for influenza-like illness (ILI)in Denmark, a year-round electronic reporting system was established in collaboration with the Danish medical on-call service (DMOS). In order to achieve real-time surveillance of ILI, a checkbox for ILI was inserted in the electronic health record and a system for daily transfer of data to the national surveillance centre was implemented. The weekly number of all consultations in DMOS was around 60,000, and activity of ILI peaked in week 46 of 2009 when 9.5% of 73,723 consultations were classified as ILI. The incidence of ILI reached a maximum on 16 November 2009 for individuals between five and 24 years of age, followed by peaks in children under five years, adults aged between 25 and 64 years and on 27 November in senior citizens(65 years old or older). In addition to the established influenza surveillance system, this novel system was useful because it was timelier than the sentinel surveillance system and allowed for a detailed situational analysis including subgroup analysis on a daily basis.

Agreement between accelerometric symmetry scores and clinical lameness scores during experimentally induced transient distension of the metacarpophalangeal joint in horses.

REASONS FOR PERFORMING STUDY: Equine lameness examination is based on subjective visual scoring of lameness. Instrumented objective methods for lameness examinations may be complicated to perform and the equipment is often stationary. Accelerometry has a potential clinical use; however, the reduction and interpretation of equine accelerometric data are not yet routine and the value of accelerometry in equine lameness examination is unclear. OBJECTIVES: To use accelerometric data to calculate 2 different accelerometric symmetry scores and to evaluate the agreement of these with traditional lameness scores done by experienced equine practitioners. METHODS: Six sound horses were equipped with a 3 axis 10G piezoresistant accelerometer at the lowest point of the back. Horses were trotted and video recorded at 0, 3, 15, 30, 45 and 60 min after injection of saline into one metacarpophalangeal joint. Video recordings were scored in a blind manner according to the AAEP scale by 2 experienced practitioners. Interobserver agreements and 2 symmetry scores S and A, developed on the basis of Fourier transformation of the obtained accelerometric data, were calculated and regression analysis between AAEP scores and symmetry scores was performed. RESULTS: Interobserver agreements were 70%. There was a statistically significant relationship between AAEP lameness scores and both symmetry scores. CONCLUSIONS: Both symmetry scores showed a significant relationship with the AAEP scores and can be a valuable tool in the detection and quantification of lameness. While the S score was able to detect changes in degree of lameness, the A score was capable of detecting the lame diagonal. However, more research is needed for the development of a combined accelerometric score to take advantage of the strengths of each of the symmetry scores.

Polysynovitis after oligofructose overload in dairy cattle.

Acute bovine laminitis is a systemic disease with local manifestations primarily affecting the claws. However, distension of the tarsocrural joints has been observed after experimental oligofructose overload in dairy heifers as a part of the complex interpreted as acute, clinical laminitis. Therefore, the aim of the present study was to study bovine synovial joints and tendon sheaths after oligofructose overload. Ten dairy heifers received oral oligofructose overload (17 g/kg body weight); four were killed 24h after overload and six after 72 h. Six control heifers received tap water and were killed after 72 or 96 h. Clinical examination included locomotion scoring and palpation of the tarsocrural joints. Ruminal fluid and blood was collected for measurements of pH and hydration status. Total protein concentrations and white blood cell (WBC) counts were determined in synovial fluid collected from tarsocrural joints after death. Synovial joints and tendon sheaths were examined and synovial membranes were studied microscopically. Swabs taken from the synovial cavities were subject to bacteriological culture. Heifers with oligofructose overload developed signs of ruminal and systemic acidosis. Lameness was observed in three of ten heifers 24h after overload and in all remaining heifers after 72 h. Distension of tarsocrural joints was observed from 18 h after overload and peaked at 30 h when all examined joints were moderately or severely distended. The synovial fluid was turbid and protein content and WBC counts were increased at both 24 and 72 h compared with controls. Bacterial culture was negative. Synovial membranes 24 and 72 h after overload had a fibrinous and neutrophil inflammatory reaction that regressed in severity between 24 and 72 h after overload. Heifers subjected to oligofructose overload therefore developed generalized sterile neutrophilic polysynovitis. Focus on this aspect of bovine laminitis may shed new light on the pathogenesis of this complex disease.

Evidence of protective effect of BCG vaccination in persons at low risk of tuberculosis in Nordic countries.

SETTING: Norway, Sweden, Denmark and Finland have low incidence rates (IRs) of tuberculosis (TB) but the use of bacille Calmette-Guérin (BCG) vaccination has varied. OBJECTIVE: To assess if different IRs among persons at low risk in the four countries could be related to the different use of BCG vaccination, and to estimate the number of adolescent BCG vaccinations needed to prevent one case of TB in Norway. DESIGN: The study period was 1996-2005. In part A, IRs for cases classified as 'born in country/national' in the EuroTB database in all four countries were calculated. In part B, the IRs among persons born in Norway and Sweden with two parents from low-incidence countries were calculated for cases registered in the respective national TB registers. In both parts, IRs and IR ratios among 0-14-year-olds and 15-29-year-olds were compared and related to different BCG vaccination policies. RESULTS AND CONCLUSIONS: Our results are consistent with a protective effect of newborn BCG vaccination in native-born 0-14-year-olds in Finland, and of adolescent BCG vaccination in 15-29-year-olds in Norway. The Norwegian BCG vaccination programme conferred 61-64% protection to 15-29-year-olds; however, 21699-25125 vaccinations were needed to prevent one case.

The cytokine response of circulating peripheral blood mononuclear cells is changed after intravenous injection of lipopolysaccharide in cattle.

The aim of the study was to investigate lipopolysaccharide (LPS)-induced short and long term changes in capacity for intracellular cytokine-production of bovine circulating peripheral blood mononuclear cells (PBMCs). Eight dairy cows each received three intravenous injections of Escherichia coli LPS (10, 100 and 1000ng/kg, consecutively) at 3week intervals. Intracellular cytokine production was determined by flow cytometry in PBMCs obtained 0, 2, 6 and 24h after each LPS challenge. After LPS administration, proportions of monocytes producing tumour necrosis factor (TNF) alpha, interleukin (IL)-1beta and IL-8, as well as proportions of circulating lymphocytes producing interferon (IFN) gamma, decreased significantly. Within 24h, proportions had returned to or increased above pre-injection levels. Proportions of lymphocytes producing IL-4 and IL-10 increased significantly after injection of 1000ng LPS/kg. This study demonstrated that cytokine profiles shift quickly, but temporarily, to favour the anti-inflammatory response immediately after LPS exposure. The long term response to LPS was opposite to the immediate response, as cytokine profiles shifted in the 3weeks between challenges towards a pro-inflammatory response. Proportions of monocytes producing IL-1beta and TNFalpha determined immediately before the second and/or third LPS injection were higher than proportions determined before the first injection, whereas pre-injection proportions of lymphocytes producing IL-4 decreased with each challenge. These changes may result in a quicker host response to invading pathogens.

Tissue specific distribution of the 3243A->G mtDNA mutation.

BACKGROUND: The 3243A-->G is a common pathogenic mitochondrial DNA (mtDNA) point mutation causing a variety of different phenotypes. Segregation of this mutation to different tissues during embryonic life and postnatally is still enigmatic. OBJECTIVE: To investigate the tissue distribution of this mutation. METHODS: In 65 individuals from nine families segregating the 3243A-->G mutation, the mutation load (% mutated mtDNA) was determined in various tissues. Mutation load was measured in two to four cell types--blood leucocytes, buccal cells, skeletal muscle cells, and urine epithelial cells (UEC)--derived from all three embryogenic germ layers. RESULTS: There was a significant correlation among mutation loads in the four tissues (r = 0.80-0.89, p<0.0001). With blood serving as reference, the mutation load was increased by 16% in buccal mucosa, by 31% in UEC, and by 37% in muscle. There were significant differences between the mitotic tissues blood, buccal mucosa, and UEC (p<0.0001), but no difference between UEC and muscle. Using the present data as a cross sectional investigation, a negative correlation of age with the mutation load was found in blood, while the mutation load in muscle did not change with time; 75% of the children presented with higher mutation loads than their mothers in mitotic tissues but not in the post-mitotic muscle. CONCLUSIONS: There appears to be a uniform distribution of mutant mtDNA throughout the three germ layers in embryogenesis. The significant differences between mutation loads of the individual tissue types indicate tissue specific segregation of the 3243A-->G mtDNA later in embryogenesis.