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Analysis of Regional Mechanics in Canine Lung Injury Using Forced Oscillations and 3D Image Registration
Acute lung injury is characterized by heterogeneity of regional mechanical properties, which is thought to be correlated with disease severity. The feasibility of using respiratory input impedance () and computed tomographic (CT) image registration for assessing parenchymal mechanical heterogeneity was evaluated. In six dogs, measurements of () before and after oleic acid injury at various distending pressures were obtained, followed by whole lung CT scans. Each () spectrum was fit with a model incorporating variable distributions of regional compliances. CT image pairs at different inflation pressures were matched using an image registration algorithm, from which distributions of regional compliances from the resulting anatomic deformation fields were computed. Under baseline conditions, average model compliance decreased with increasing inflation pressure, reflecting parenchymal stiffening. After lung injury, these average compliances decreased at each pressure, indicating derecruitment, alveolar flooding, or alterations in intrinsic tissue elastance. However, average compliance did not change as inflation pressure increased, consistent with simultaneous recruitment and strain stiffening. Image registration revealed peaked distributions of regional compliances, and that small portions of the lung might undergo relative compression during inflation. The authors conclude that assessments of lung function using () combined with the structural alterations inferred from image registration provide unique but complementary information on the mechanical derangements associated with lung injury
Vitamins D and K as Factors Associated with Osteopathy in Chronic Pancreatitis. A Prospective Multicentre Study (P-BONE Study)
Background: Osteopathy is common in patients with chronic pancreatitis (CP), but previous studies carry several limitations. Vitamin K is essential for bone metabolism, but its role in this setting has never been investigated. Our aim is to assess the prevalence of osteoporosis and osteopenia in CP patients, and to investigate the association between osteopathy and CP features and nutritional parameters, especially vitamin D and K levels. Methods: Multicentre cross-sectional study on CP patients diagnosed according to M-ANNHEIM criteria. Bone density was evaluated by dual-energy X-ray absorptiometry and pancreatic function by faecal elastase. Nutritional evaluation included vitamin D and vitamin K. Differences between patients with or without osteopathy were evaluated. The association between investigated variables and bone density were analysed with logistic regression analysis. Results: In total, 211 CP patients were enrolled at eight Centres (67% men; mean age 60). In total, 18% had advanced-marked CP, 56% suffered from pancreatic exocrine insufficiency and disease aetiology was alcoholic in 43%. Vitamin D and K were deficient in 56% and 32%, respectively. Osteopenia was diagnosed in 42% and osteoporosis in 22%. In the multivariate analysis, female sex (OR 2.78), age (OR 1.07 per year) and higher BMI (OR 0.84) were associated with the presence of osteoporosis. In male patients, the only factor associated with osteoporosis was vitamin K deficiency (OR 4.23). Conclusion: The present data confirm a high rate of osteopathy in CP patients and highlight the relevance of vitamin K deficiency as only factor associated with osteoporosis in male patients for the first time
Tree rings of Scots pine (Pinus sylvestris L.) as a source of information about past climate in northern Poland
Scots pine (Pinus sylvestris) is a very common tree in Polish forests, and therefore was widely used as timber. A relatively large amount of available wood allowed a long-term chronology to be built up and used as a source of information about past climate. The analysis of reconstructed indexed values of mean temperature in 51-year moving intervals allowed the recognition of the coldest periods in the years 1207–1346, 1383–1425, 1455–1482, 1533–1574, 1627–1646, and 1694–1785. The analysis of extreme wide and narrow rings forms a complementary method of examining climatic data within tree rings. The tree ring widths, early wood and late wood widths of 16 samples were assessed during the period 1581–1676. The most apparent effect is noted in the dry summer of 1616. According to previous research and our findings, temperature from February to March seems to be one of the most stable climatic factors which influenced pine growth in Poland. Correlation coefficients in the calibration and validation procedure gave promising results for temperature reconstruction from the pine chronology
Diagnosis and treatment of thyroid cancer in children in the multicenter analysis in Poland for PPGGL
Introduction: Differentiated thyroid carcinoma (DTC) in
children presents different biological behavior in comparison
to adults. Authors presents preliminary results of multicenter
analysis concerning incidence, diagnostics and treatment
of DTC in children.
Material and methods: The study is a retrospective analysis
of 107 pediatric patients from 14 academic centers based
on the data from 2000 to 2005 obtained by questionnaire in
hospitals involved in the treatment of DTC in children.
Results: Papillary thyroid cancer was diagnosed in 83 children,
follicular thyroid cancer in 10 children and medullary
thyroid cancer in 14 children. Incidence of DTC in children
was estimated between 18 and 23 cases per year. The biggest
group of patients consisted of children between 11 and
15 years of age, with girls to boys ratio 3.3 : 1. Clinically DTC
in children presented most often as solitary thyroid nodule.
Cervical lymphadenopathy was observed in 42% of patients.
Intraoperative verification indicated metastatic nodes
in 50% of children. Low stage DTC predominated (T1
in 36% and T2 in 26% of children). One step surgery was performed in 65% of children with DTC, two step surgery
in 25% of patients. I131 therapy was undertaken in 80% of
children. Lung metastases were indicated in post therapeutic
studies in 14% of children with DTC. Prophylactic thyroidectomies
were performed in 79% of children in the group
of patients with MTC and RET gene mutations.
Conclusions: The necessity of introduction of unified therapeutic
standard in children with DTC in Poland is underlined.Wstęp: Zróżnicowane raki tarczycy (DTC, differentiated thyroid
carcinoma) występują u dzieci rzadko. Większość przypadków
wykrywanych jest w wieku 11-17 lat. W odróżnieniu
od dorosłych DTC u dzieci prezentują odmienne zachowanie
biologiczne. Mała liczba przypadków DTC
w poszczególnych ośrodkach oraz względnie łagodny ich
przebieg utrudniają ocenę występowania i leczenia DTC
u dzieci w Polsce, uzależniając ją od wysiłków włożonych
w uzyskanie rzetelnych danych. Autorzy przedstawiają
wstępne wyniki analizy wieloośrodkowej dotyczące występowania,
diagnostyki i leczenia DTC u dzieci.
Materiał i metody: Podjęte badania są retrospektywną analizą
obejmującą lata 2000-2005, opartą na danych z historii
chorób uzyskanych z ankiet rozesłanych do ośrodków dla
dzieci i dorosłych podejmujących leczenie DTC. Do analizy
zgłoszono 107 pacjentów z 14 ośrodków akademickich
w Polsce. Analizie poddano wiek i płeć dzieci z DTC, wielkość
i lokalizację zmian w tarczycy, sposoby rozpoznawania
DTC, rodzaje i zakres wykonywanych zabiegów operacyjnych
oraz leczenie uzupełniające izotopem J131.
Wyniki: Raka brodawkowatego stwierdzono u 83 dzieci,
pęcherzykowego u 10 dzieci, a rdzeniastego u 14 dzieci. Częstość
występowania DTC u dzieci w Polsce wahała się między
18 a 23 przypadkami rocznie. W województwach: mazowieckim
i połączonych wielkopolskim i lubuskim wykazano
w okresie 2000-2005 wyższą (24 i 25) częstość występowania
DTC, w pozostałych województwach wykazywano
od 2 do 10 przypadków DTC. Największą grupę pacjentów
stanowiły dzieci w wieku 11-15 lat, a stosunek dziewcząt do chłopców wynosił 3,3 : 1. Klinicznie DTC prezentowały
się najczęściej jako pojedyncze guzki tarczycy. Limfadenopatię
szyjną w badaniu klinicznym stwierdzono
u 42% pacjentów, a śródoperacyjnie u 50% dzieci. U większości
pacjentów dominowały niższe stopnie zaawansowania
DTC (T1 u 36% i T2 u 26% dzieci). Operacje jednoetapowe
wykonano u 65% dzieci, operacje dwuetapowe u 25%
dzieci, a profilaktyczne tyreoidektomie u 79% dzieci z grupy
pacjentów z rakiem rdzeniastym tarczycy (MTC, medullary
thyroid cancinoma) i mutacją genu Ret. Leczenie izotopowe
J131 podjęto u 80% dzieci. Przerzuty do płuc w scyntygrafii
poterapeutycznej wykazano u 14% dzieci z DTC.
Wnioski: We wnioskach podkreśla się konieczność wdrożenia
na terenie całego kraju ujednoliconego i ocenianego
na podstawie obiektywnych przesłanek sposobu postępowania
z dziećmi z DTC
No systematic effects of sampling direction on climate-growth relationships in a large-scale, multi-species tree-ring data set
Ring-width series are important for diverse fields of research such as the study of past climate, forest ecology, forest genetics, and the determination of origin (dendro-provenancing) or dating of archaeological objects. Recent research suggests diverging climate-growth relationships in tree-rings due to the cardinal direction of extracting the tree cores (i.e. direction-specific effect). This presents an understudied source of bias that potentially affects many data sets in tree-ring research. In this study, we investigated possible direction-specific growth variability based on an international (10 countries), multi-species (8 species) tree-ring width network encompassing 22 sites. To estimate the effect of direction-specific growth variability on climate-growth relationships, we applied a combination of three methods: An analysis of signal strength differences, a Principal Component Gradient Analysis and a test on the direction-specific differences in correlations between indexed ring-widths series and climate variables. We found no evidence for systematic direction-specific effects on tree radial growth variability in high-pass filtered ring-width series. In addition, direction-specific growth showed only marginal effects on climate-growth correlations. These findings therefore indicate that there is no consistent bias caused by coring direction in data sets used for diverse dendrochronological applications on relatively mesic sites within forests in flat terrain, as were studied here. However, in extremely dry, warm or cold environments, or on steep slopes, and for different life-forms such as shrubs, further research is advisable.</p
Regional Patterns of Late Medieval and Early Modern European Building Activity Revealed by Felling Dates
Although variations in building activity are a useful indicator of societal well-being and demographic development, historical datasets for larger regions and longer periods are still rare. Here, we present 54,045 annually precise dendrochronological felling dates from historical construction timber from across most of Europe between 1250 and 1699 CE to infer variations in building activity. We use geostatistical techniques to compare spatiotemporal dynamics in past European building activity against independent demographic, economic, social and climatic data. We show that the felling dates capture major geographical patterns of demographic trends, especially in regions with dense data coverage. A particularly strong negative association is found between grain prices and the number of felling dates. In addition, a significant positive association is found between the number of felling dates and mining activity. These strong associations, with well-known macro-economic indicators from pre-industrial Europe, corroborate the use of felling dates as an independent source for exploring large-scale fluctuations of societal well-being and demographic development. Three prominent examples are the building boom in the Hanseatic League region of northeastern Germany during the 13th century, the onset of the Late Medieval Crisis in much of Europec. 1300, and the cessation of building activity in large parts of central Europe during armed conflicts such as the Thirty Years’ War (1618–1648 CE). Despite new insights gained from our European-wide felling date inventory, further studies are needed to investigate changes in construction activity of high versus low status buildings, and of urban versus rural buildings, and to compare those results with a variety of historical documentary sources and natural proxy archives.</jats:p
Deficiency of fat-soluble vitamins in chronic pancreatitis: a systematic review and meta-analysis
Background and aims Chronic pancreatitis (CP) patients are at risk for fat-soluble vitamins (A, D, E, K) deficiency, but available studies are small and heterogeneous. We conducted a systematic review and meta-analysis to determine the prevalence of fat–soluble vitamins deficiency in CP patients. Methods Medline was searched up to January 2016 for case series and case-control studies reporting prevalence of fat-soluble vitamin deficiency in CP patients. The prevalent deficiency rate was pooled for included studies, and deficiency rate between CP and controls, with relative odds ratio (OR) and 95% confidence interval (CI) calculated for case-control studies. Results Twelve studies including 548 patients included. With a random-effect model, the pooled prevalence rate of vitamin A, D and E deficiency were 16.8% (95%CI 6.9–35.7), 57.6% (95%CI 43.9–70.4) and 29.2% (95%CI 8.6–64.5) respectively, with considerable heterogeneity (I2 = 75%, 87.1% and 92%). Only one study evaluated vitamin K deficiency. The pooled OR for vitamin D deficiency in CP cases compared with controls was 1.17 (95% CI 0.77–1.78). Sensitivity analyses showed lower prevalence of vitamin A and E, and higher prevalence of vitamin D deficiency in high-quality studies. The rate of pancreatic exocrine insufficiency did not seem affect the deficiency rates, while the use of different cut-offs influences results and heterogeneity for vitamin E, but not A. Conclusions Fat-soluble vitamins deficiency is frequent in CP patients, with considerable heterogeneity. There is, however, no apparent increased risk of vitamin D deficiency in CP compared to controls. Larger, high-quality studies are necessary to better estimate the prevalence of fat-soluble vitamins deficiency, including vitamin K
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