Low major histocompatibility complex class II diversity in European and North American moose.

Major histocompatibility complex (MHC) genes encode cell surface proteins whose function is to bind and present intracellularly processed peptides to T lymphocytes of the immune system. Extensive MHC diversity has been documented in many species and is maintained by some form of balancing selection. We report here that both European and North American populations of moose (Alces alces) exhibit very low levels of genetic diversity at an expressed MHC class II DRB locus. The observed polymorphism was restricted to six amino acid substitutions, all in the peptide binding site, and four of these were shared between continents. The data imply that the moose have lost MHC diversity in a population bottleneck, prior to the divergence of the Old and New World subspecies. Sequence analysis of mtDNA showed that the two subspecies diverged at least 100,000 years ago. Thus, viable moose populations with very restricted MHC diversity have been maintained for a long period of time. Both positive selection for polymorphism and intraexonic recombination have contributed to the generation of MHC diversity after the putative bottleneck.     

Health-related quality of life in adults after repair of congenital diaphragmatic defects--a questionnaire study

Background and Aim

Long-term respiratory, gastrointestinal, and vertebral sequelae are common after repair of congenital diaphragmatic defects (CDDs). The aim of this study was to assess the effect of these sequelae on the health-related quality of life (HRQoL) of adult survivors after CDD repair.

Materials and Methods

A questionnaire, including 36-Item Health Survey Form (SF-36), 36-item Gastrointestinal Quality of Life Index (GIQLI), 55-item Psychosocial Survey, 9-item survey for Respiratory Symptoms-Related Quality of Life Index, and a symptoms query, was sent to 94 adult survivors of CDD and to 400 healthy control subjects. One SD lower than the age-adjusted national average in the 36-Item Health Survey Form score for physical or mental health was considered as low HRQoL.

Results

Sixty-nine patients with CDD (72%) and 162 (41%) control subjects returned the questionnaire. The initial presentation was critical in less than 10% of patients with CDD. Forty-five patients with diaphragmatic hernia had primary closure; in 1 patient with diaphragmatic hernia, a patch was used. Twenty-four patients had plication of diaphragmatic eventration. The incidence of gastroesophageal reflux (20% vs 2%), recurrent intestinal obstruction (7% vs 0%), and recurrent abdominal pain (12% vs 2%) was significantly higher in patients with CDD than in control subjects, whereas no difference in the incidence of respiratory, musculoskeletal, or other health problems not associated with CDD was found. Scores in GIQLI, Psychosocial Survey, and Respiratory Symptoms-Related Quality of Life Index did not differ between patients with CDD and control subjects. Health-related quality of life was low in 17 (25%) of 69 patients with CDD, which exceeded 1.5 times the expected value. There was no correlation between the type or severity of the primary defect and HRQoL at the time of the study.

Conclusion

Most adults with repaired CDD have good or satisfactory HRQoL. Congenital diaphragmatic defect-associated symptoms with or without acquired diseases significantly impair HRQoL in one fourth of the patients.     

Motion detection and correction for dynamic 15O-water myocardial perfusion PET studies

Purpose Patient motion during dynamic PET studies is a well-documented source of errors. The purpose of this study was to investigate the incidence of frame-to-frame motion in dynamic ¹⁵O-water myocardial perfusion PET studies, to test the efficacy of motion correction methods and to study whether implementation of motion correction would have an impact on the perfusion results.Methods We developed a motion detection procedure using external radioactive skin markers and frame-to-frame alignment. To evaluate motion, marker coordinates inside the field of view were determined in each frame for each study. The highest number of frames with identical spatial coordinates during the study were defined as non-moved. Movement was considered present if even one marker changed position, by one pixel/frame compared with reference, in one axis, and such frames were defined as moved. We tested manual, in-house-developed motion correction software and an automatic motion correction using a rigid body point model implemented in MIPAV (Medical Image Processing, Analysis and Visualisation) software. After motion correction, remaining motion was re-analysed. Myocardial blood flow (MBF) values were calculated for both non-corrected and motion-corrected datasets.Results At rest, patient motion was found in 18% of the frames, but during pharmacological stress the fraction increased to 45% and during physical exercise it rose to 80%. Both motion correction algorithms significantly decreased (p<0.006) the number of moved frames and the amplitude of motion (p<0.04). Motion correction significantly increased MBF results during bicycle exercise (p<0.02). At rest or during adenosine infusion, the motion correction had no significant effects on MBF values.Conclusion Significant motion is a common phenomenon in dynamic cardiac studies during adenosine infusion but especially during exercise. Applying motion correction for the data acquired during exercise clearly changed the MBF results, indicating that motion correction is required for these studies.     

Small bowel cyclooxygenase 2 (COX-2) expression in patients with IgA nephropathy

BACKGROUND: Clinical manifestation of IgA nephropathy (IgAN) strikingly occurs after respiratory tract infections. An intestinal inflammation has also been described. We hypothesized that the intestinal inflammation should manifest itself as an increase in inflammatory cells and mucosal cyclooxygenase 2 (COX-2) expression. METHODS: By using immunohistochemistry, we determined the phenotype and quantity of inflammatory cells in duodenal biopsy specimens from 17 IgAN patients. Control material comprised 18 patients undergoing gastroscopy because of dyspepsia. RESULTS: All the biopsy specimens disclosed normal villous architecture. In IgAN, CD3(+) cells and COX-2-positive cells were significantly increased and J chain-producing plasma cells were significantly decreased. CD3(+) cells coexpressed COX-2 protein and COX-2-positive cells also expressed CD45RO antigen. The number of lymphocytes correlated significantly with serum IgA and COX-2-expression with serum IgA and the degree of hematuria. COX-2-positive subepithelial fibroblasts were a conspicuous finding in IgAN. In CD68(+) and CD15(+) cells, a significant increase was seen. Many of these cells also expressed COX-2 protein. CD15(+) positivity correlated significantly with proteinuria in IgAN. CONCLUSION: Our results indicate that small bowel inflammation in IgAN shows itself as an increased number of mucosal inflammatory cells. However, polymeric IgA production is significantly decreased. An increased mucosal COX-2 expression suggests activation of the inflammatory cells and the degree of inflammation significantly correlates with serum IgA and the amount of proteinuria and hematuria. Subepithelial fibroblasts seem also to be involved in the inflammatory reaction.     

Ultrasound assessment of endothelial function in children

Although the clinical complications of atherosclerosis arise from developed lesions in old age, the atherosclerotic disease is a lifelong process with roots in childhood. Endothelial dysfunction is currently considered an early stage in the pathogenesis of atherosclerosis, which precedes the formation of structural atherosclerotic changes. Improvements in noninvasive imaging modalities, mainly in ultrasound imaging, have made it possible to assess the endothelial health of asymptomatic children with or without cardiovascular risk factors. By using noninvasive ultrasound for endothelial function, important insights have been gained into the early stages of atherosclerosis and the effects of cardiovascular risk factors on vasculature in childhood. The ultrasound test of endothelial function is affordable, available, and safe and may be considered a potent aid in clinical risk stratification of children at high risk for subsequent clinical atherosclerosis in adulthood. At present, this methodology serves only research purposes, as many issues including reproducibility and normal values for healthy children need to be solved before clinical use can be considered. In adults, however, recent studies have shown that attenuated endothelial function predicts the occurrence of future cardiovascular events.     

Circannual rhythm in the incidence of cryptorchidism in Finland

Conflicting data on circannual variation in birth rates of urogenital malformations have been reported previously. To assess risk factors of cryptorchidism we studied the seasonal variation of cryptorchidism in Finland. We performed a prospective cryptorchidism study in Turku, Finland, from 1997 to 2001 to evaluate the incidence of cryptorchidism. Clinical examinations were performed at birth and at 3 months. Of 9511 liveborn boys (1471 preterm boys) 216 (53 preterm boys) were cryptorchid at birth and 106 (19 preterm boys) at 3 months. The incidence of cryptorchidism was significantly higher in spring (February-April) (3.0%) than in summer (May-July) (1.7%) (OR 1.79; 95% CI: 1.23-2.63). This seasonal difference was observed both among preterm and term boys. We conclude that a circannual fluctuation in the incidence of cryptorchidism exists, which indicates an influence by environmental factors. The underlying reason for cyclicity affects similarly both preterm and term boys.     

A combination of three common inherited mitochondrial DNA polymorphisms promotes longevity in Finnish and Japanese subjects

Mitochondrial DNA (mtDNA) coding region polymorphisms, as well as the 150T polymorphism in the noncoding region, have been associated with longevity. We have studied here the association of 150T with longevity further and assessed differences in this association between various mtDNA haplogroups. We analysed a sample of 321 very old subjects and 489 middle-aged controls from Finland and Japan. 150T was more frequent among the very old than among the controls in both the Finnish and Japanese subjects. Interestingly, the association was not similar in all haplogroups, and a stratified analysis revealed that two additional common polymorphisms, 489C and 10398G, modified the association between 150T and longevity. These findings suggest that longevity is partly determined by epistatic interactions involving these three mtDNA loci.     

Unilateral pallidotomy in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated common marmosets exhibiting levodopa-induced dyskinesia

Pallidotomy paradoxically reduces the intensity of levodopa-induced dyskinesia without worsening motor symptoms. The reasons for this are not clear and no experimental study has investigated this phenomenon. The objective of this investigation was to evaluate the effects of unilateral pallidotomy on locomotor activity, motor disability and levodopa-induced dyskinesia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated levodopa-primed common marmosets. Animals were primed to exhibit dyskinesia by daily administration of levodopa until stable dyskinesia was evoked by each dose. Locomotor activity, motor disability and dyskinesia were assessed weekly at baseline and following an acute levodopa challenge. Prior to pallidotomies, two distinct groups of animals emerged: poor responders to levodopa with mild dyskinesia (Group 1) and those exhibiting a marked increase in motor activity and pronounced dyskinesia (Group 2). Electrolytic lesions were placed in the left internal segment of the globus pallidus. Pallidotomy had no effect on basal or levodopa-induced motor activity in either group but significantly improved basal motor disability in Group 2. Following pallidotomy, the ability of levodopa to reduce motor disability was significantly increased in both groups. Pallidotomy improved dyskinesia in both Groups 1 and 2 but it was more effective in reducing dystonia compared with chorea. The effect of pallidotomy on dyskinesia in Group 2 was transient, with the intensity of involuntary movements reverting to presurgery levels 4 weeks later. This study shows that in levodopa-primed, parkinsonian marmosets, placement of discrete globus pallidus lesions can ameliorate levodopa-induced dyskinesia but not akinesia. This model allows the evaluation of pallidotomy-induced biochemical changes in dyskinetic primates.