The capacity of particles to increase allergic sensitization is predicted by particle number and surface area, not by particle mass.

Particle exposure has traditionally been monitored as mass concentration of PM10 (particles with an aerodynamic diameter less than 10 microm), more recently also as PM2.5. The mass concentration is strongly influenced by the large particles. Therefore, particle mass is a poor measure for characterizing the amount of the small, possibly more biologically potent particles. We used polystyrene particles (PSP) ranging in diameter from 0.0588 to 11.14 microm, carbon black (CB), and diesel exhaust particles (DEP), to study the adjuvant effect of particles on the immune response to the allergen ovalbumin (OVA) after sc injection into the footpad of BALB/cA mice. At a given mass dose, the small particles (0.0588 and 0.202 microm PSP, CB, and DEP) increased the allergen-specific IgE serum levels to a substantially higher degree than the larger particles (1.053, 4.64, and 11.14 microm PSP). Further, in the draining lymph node during the primary response, the fine particles (0.202 microm) with OVA increased cell numbers, expression of surface markers (CD19, MHC class II, CD86, and CD23) and ex vivo production of IL-4 and IL-10, whereas the largest (11.14 microm) particles did not. Linear regression analyses indicated that the IgE response was not predicted by particle mass (R2 = 0.06), but was predicted by the total particle surface area (R2 = 0.64), number of particles (R2 = 0.62), and particle diameter (R2 = 0.58). In conclusion, we found that fine particles exerted stronger adjuvant effects on allergic responses than larger particles at equal mass doses. Consequently, the dose described as total particle surface area or particle number predicts the adjuvant effect of particles better than the currently used particle mass.     

Personality, physical activity, and symptoms of anxiety and depression: the HUNT study

Purpose

To analyze the association between physical activity (PA), symptoms of depression and anxiety, and personality traits.

Methods

Cross-sectional study from a Norwegian population-based survey conducted in the period 2006–2008. The sample consisted of a total of 38,743 subjects aged ≥19 years, 56.1 % women and 43.9 % men. Demographic variables, PA, depression and anxiety (The Hospital Anxiety and Depression Scale), and personality (Eysenck Personality Questionnaire) were assessed by self-reporting measurements.

Results

Individuals who reported moderate and high PA had significantly lower scores on depression and anxiety compared with less physically active individuals (p < 0.05). Significantly lower risk of HADS-defined depression and anxiety was associated with frequency, duration, and intensity of activity among women (p < 0.05), and significantly lower risk of HADS-defined depression was associated with frequency, duration, and intensity of activity among men (p < 0.05). There was a significant linear trend between extroversion and levels of PA (p < 0.01) and between neuroticism and PA (p < 0.01).

Conclusions

Subjects reporting regular leisure-time PA were less likely to report symptoms of HADS-defined depression and anxiety. Personality may be an underlying factor in explaining this association.     

Pain tolerance after stroke: The Tromsø study

Background

Stroke lesions might alter pain processing and modulation by affecting the widely distributed network of brain regions involved. We aimed to compare pain tolerance in stroke survivors and stroke-free persons in the general population, with and without chronic pain.

Methods

We included all participants of the sixth and seventh wave of the population-based Tromsø Study who had been tested with the cold pressor test (hand in cold water bath, 3°C, maximum time 106 s in the sixth wave and 120 s in the seventh) and who had information on previous stroke status and covariates. Data on stroke status were obtained from the Tromsø Study Cardiovascular Disease Register and the Norwegian Stroke Register. Cox regression models were fitted using stroke prior to study attendance as the independent variable, cold pressor endurance time as time variable and hand withdrawal from cold water as event. Statistical adjustments were made for age, sex, diabetes, hypertension, hyperlipidaemia, body mass index and smoking.

Results

In total 21,837 participants were included, 311 of them with previous stroke. Stroke was associated with decreased cold pain tolerance time, with 28% increased hazard of hand withdrawal (hazard ratio [HR] 1.28, 95% CI 1.10–1.50). The effect was similar in participants with (HR 1.28, 95% CI 0.99–1.66) and without chronic pain (HR 1.29, 95% CI 1.04–1.59).

Conclusions

Stroke survivors, with and without chronic pain, had lower cold pressor pain tolerance, with possible clinical implications for pain in this group.

Significance

We found lower pain tolerance in participants with previous stroke compared to stroke-free participants of a large, population-based study. The association was present both in those with and without chronic pain. The results may warrant increased awareness by health professionals towards pain experienced by stroke patients in response to injuries, diseases and procedures.     

Indirect CD4+ T‐cell‐mediated elimination of MHC IINEG tumor cells is spatially restricted and fails to prevent escape of antigen‐negative cells

Tumor‐specific Th1 cells can activate tumor‐infiltrating macrophages that eliminate MHC class II negative (MHC II^NEG) tumor cells. Activated M1‐like macrophages lack antigen (Ag) receptors, and are presumably unable to discriminate and thus kill both Ag‐positive (Ag^POS) and Ag‐negative (Ag^NEG) tumor cells (bystander killing). The lack of specificity of macrophage‐mediated cytotoxicity might be of clinical importance as it could provide a means of avoiding tumor escape. Here, we have tested this idea using mixed populations of Ag^POS and Ag^NEG tumor cells in a TCR‐transgenic model in which CD4⁺ T cells recognize a secreted tumor‐specific antigen. Surprisingly, while Ag^POS tumor cells were recognized and rejected, Ag^NEG cells grew unimpeded and formed tumors. We further demonstrated that macrophage‐mediated cytotoxicity was spatially restricted to areas dominated by Ag^POS tumor cells, sparing Ag^NEG tumor cells in the vicinity. As a consequence, macrophage tumoricidal activity did not confer bystander killing in vivo. The present results offer novel insight into the mechanisms of indirect Th1‐mediated elimination of MHC II^NEG tumor cells.     

Hormone replacement therapy does not affect plasma homocysteine in postmenopausal women with coronary artery disease. Free tissue factor pathway inhibitor antigen,a circulating anticoagulant,is related to plasma homocysteine

OBJECTIVE: The objective was to evaluate the effect of hormone replacement therapy (HRT) on plasma homocysteine levels in postmenopausal women with coronary artery disease (CAD) and to investigate associations of homocysteine to other cardiovascular risk factors. METHODS: The women in this single-center, controlled, and randomized study were examined at baseline, and after 3 and 12 months, after they had been recruited consecutively from patients referred for investigational coronary angiography. All analyses were performed examiner blind. They were randomized to HRT consisting of transdermal application of continuous 17beta-estradiol with cyclic medroxyprogesterone acetate (MPA) tablets for 14 days every 3rd month, or to a control group. RESULTS: After 3 months of unopposed 17beta-estradiol, no significant effect on homocysteine was observed compared to the control group. The absolute decrease of 5% in median plasma homocysteine levels after 12-month HRT did not reach statistical significance. Plasma homocysteine seemed slightly higher in women with three- or four-vessel disease, but the difference was not significant. With increasing homocysteine levels, free tissue factor pathway inhibitor (TFPI) antigen increased, whereas E-selectin decreased. In women with diabetes or elevated blood glucose >6.0 mmol/l, plasma homocysteine was correlated to body mass index, C-peptide and insulin as well as age. CONCLUSION: Transdermal application of 17beta-estradiol and sequential MPA do not affect plasma homocysteine in women with established CAD. Plasma homocysteine is stable in women with CAD over time, and unless special intervention is undertaken, repetitive measurements are not necessary in this particular group of high-risk individuals. The circulating anticoagulant TEPI is related to plasma homocysteine.     

Prognosis of facial growth in patients with unilateral complete clefts of the lip, alveolus and palate.

AIM: Unfavourable facial growth in patients with cleft lip, alveolus, and palate may occur during puberty. Usually this development is not predictable in a young patient. The aim of the present study was to find an individual growth prediction at an early age that would allow us to decide whether later orthognathic surgery should be included in the treatment plan. MATERIAL AND METHODS: Lateral cephalograms of 41 patients with unilateral clefts of lip, alveolus and palate (uCLAP) with observation intervals of 4 years were computerized, correlations between the variables of the first and second radiograph were calculated and regression equations were established. RESULTS: The skeletal change of the intermaxillary relationship can be explained purely by the lack of midfacial growth. An individual prediction of the angle SNA over a period of 4 years is possible with a correlation coefficient of 0.95. Additional predictions for SNB, Holdaway angle and the index of anterior facial height proportions are demonstrated. CONCLUSION: The prediction procedure elaborated in this paper facilitates the decision at the age of 12 years already, whether or not orthodontic occlusal treatment has been successfully completed at an early age. The alternative is to limit orthodontic treatment to the simple alignment of the two dental arches independently of their intermaxillary relation, and then to correct the facial skeleton and the dental occlusion simultaneously by combining surgical and orthodontic treatment after the completion of growth.     

Iatrogenic bile duct injuries

During a 25-year period (1959–1984), 42 patients with iatrogenic bile duct damage were referred. Before referral, 11 patients had no attempt at reconstruction, while 31 had undergone 41 operations to repair the damage. At admission, 4 patients had secondary biliary cirrhosis, 1 had portal vein thrombosis, and 1 had sepsis. The entire extrahepatic duct system had been resected in 1 patient, and operative treatment includes 41 patients. Fifty-two operations have been performed, and 34 patients (83%) have had an excellent long-term result, median 13 years. Five patients had 4 operations or more (before and after referral), and 3 are alive in good condition. Various methods of repair were employed, and 8 patients (20%) had recurrence of stricture. Restricture was lowest for hepaticojejunostomy Roux-en-Y (15%), in particular when no stent was used across the anastomosis (8%). The hospital mortality rate was 2 (5%) of 41 and overall mortality, 7 (17%) of 41. The lowest mortality rate (9%) was associated with hepaticojejunostomy Roux-en-Y. Low rate of recurrence and mortality are correlated to early referral. Patients who had restricture or died were referred a median 5 and 7 months, respectively, later than those who did well. Mortality was also related to serious complications at the time of referral and lack of follow-up. Patients with iatrogenic bile duct injury should be referred early to a competent center, where adequate treatment of infection, reconstruction with a hepaticoje-junostomy Roux-en-Y without stenting, and lifelong follow-up can be performed.

---

Resumen En el curso de un período de 25 años (1959-1984), fueron referidos 42 pacientes con lesión iatrogénica del conducto biliar. Anterior a la referencia, 11 no habfan sido sometidos a reconstruction, mientras 31 habfan sido sometidos a 41 operaciones para reparar la lesión. En el momento de la admisión, 4 pacientes presentaban cirrosis biliar secundaria, 1 presentaba trombosis de la vena porta, y 1, sepsis. La totalidad del sistema ductal extrahepático había sido resecado en 1 paciente; el tratamiento operatorio fue realizado en los 41 pacientes. Cincuenta y dos operaciones fueron realizadas, y 34 pacientes (83%) han tenido un excelente resultado a largo plazo, en un seguimiento promedio de 13 años. Cinco pacientes recibieron 4 operaciones o más (antes y después de la referencia), y 3 están vivos y en buena conditión. Varios métodos de reparatión han sido empleados; 8 pacientes (20%) desarrollaron recurrencia de la estrechez. La tasa de recurrencia fue más baja para la hepaticoyeyunostomía de Roux-en-Y (15%), particularmente cuando no se utilizó una prótesis a través de la anastomosis (8%). La mortalidad hospitalaria fue de 2 entre 41 casos (5%) y la mortalidad global de 7 entre 41 (17%). La menor mortalidad (9%) se observó en los pacientes sometidos a hepaticoyeyunostomía de Roux-en-Y. Bajas tasas de recurrencia y de mortalidad aparecen correlacionadas con una referencia temprana. Los pacientes con estrechez recurrente y aquellos que murieron, tuvieron una referencia promedio de 5 y 7 meses respectivamente, más tardía que aquella de los pacientes que evolucionaron bien. La mortalidad también aparece relacionada con complicaciones serias en el momento de la referencia y con falta de seguimiento. Los pacientes con lesión iatrogénica del conducto biliar deben ser referidos precozmente a un centro de reconocida competencia, donde se pueda realizar el tratamiento adecuado de la infectión, la reconstrucción mediante hepáticoyeyunostomía de Roux-en-Y sin prótesis intraluminales, y un seguimiento por el resto de la vida del paciente.

---

Résumé Pendant une période de 25 ans (1959 à 1984), 42 patients présentant une lésion biliaire iatrogénique ont été adressés aux auteurs. Auparavant, 11 n'avaient subi aucune intervention réparatrice alors que 31 d'entre eux avaient subi une ou plusieurs interventions (41 opérations pour 31 malades). Lors de l'admission, 4 malades présentaient une cirrhose biliaire secondaire, 1 accusait une thrombose de la veine porte, 1 était en proie à une infection. Chez 1 des 41 sujets la totalité de l'arbre biliaire extra-hépatique avait été réséqué. Au total 41 malades sur 42 ont été opérés. Cinquante-deux opérations ont été accomplies. Trente-quatre opérés (83%) ont eu un bon résultat à long terme (médiane: 13 ans), cinq patients ont subi 4 opérations ou plus (avant ou après l'admission), et 3 sont en excellente santé. Différentes opérations reconstructives ont été pratiquées et 8 malades (20%) ont été victimes d'une récidive de la sténose. La nouvelle sténose fut plus rare après hépaticojé-junostomie sur anse en Y à la Roux, en particulier lorsque l'anastomose avait été effectuée sans drain interne (8%). La mortalité hospitalière a été de 5% (2 malades décédés) et la mortalité globale de 17% (7 malades décédés). La mortalité la plus basse (9%) a été observée après hépatico-jéjunostomie. Le taux le plus bas de récidive et de mortalité a été constaté quand le malade a été adressé rapidement, en effet les malades qui ont présenté une récidive ou qui sont morts, ont été reÇus respectivement 5 à 7 mois plus tard après l'origine de la lésion que ceux qui eurent des suites favorables. La mortalité fut fonction aussi de l'existence de complications au moment de l'admission ou de l'absence de suivi après l'intervention initiale. En conclusion, les malades qui sont victimes d'une lésion iatrogénique des voies biliaires doivent Être adressés rapidement à un centre spécialisé ou un traitement adéquat de l'infection, une reconstruction biliaire par hépatico-jéjunostomie sans drain tuteur et un suivi prolongé toute la vie peuvent Être entrepris.