Lumbar disc degeneration in relation to occupation

Angiogenic growth factors are essential for cancer metastasis, and the growth of metastatic foci also depends on these angiogenic growth factors as well as autocrine or paracrine growth factors. We therefore investigated whether vascular endothelial growth factor (VEGF) and thymidine phosphorylase (dThdPase) are localized more often in primary tumors with hepatic metastasis than in those without such metastasis and whether transforming growth factor (TGF-alpha) and epidermal growth factor receptor (EGF-R) are coexisted more often in hepatic metastases than in primary tumors of gastric cancer. Resected specimens from 82 patients with gastric cancer were examined immunohistochemically. The primary antibodies used were anti-VEGF, anti-dThdPase, anti-TGF-alpha and anti-EGF-R. VEGF expression was found to be higher in primary cancers with than in those without hepatic metastasis (p < 0.001), while VEGF was frequently observed in both hepatic metastases and in the primary tumors. Localization of dThdPase was also higher in advanced than in early gastric cancers (p = 0.021). High co-presence of TGF-alpha and EGF-R was detected more frequently in cancers with deep gastric wall invasion than in those without such invasion (p = 0.050), and also more often in cancers with venous invasion (p = 0.007) and those in the advanced stage (p = 0.020). Co-presence of TGF-alpha and EGF-R was found to be higher, though not significantly, in hepatic metastases (58.8%) than in primary tumors (29.4%). These findings suggest that localization of VEGF may play an important role in hepatic metastasis, and that the expression of VEGF, dThdPase and the TGF-alpha/EGF-R pathway may be responsible for the growth of hepatic metastasis.     

Optimization of the metakaolin geopolymer preparation for maximized ammonium adsorption capacity

Geopolymers are functional materials that can be used in various environmental applications such as adsorbents in pollutant removal from wastewaters. Metakaolin geopolymer (MK-GP) has been proven to be especially suitable for ammonium (NH₄ ⁺) removal. In this research, the optimal reagent and raw material ratios in the preparation of MK-GP in terms of NH₄ ⁺ adsorption capacity were investigated. The response surface methodology based on the face-centered central composite design was used to optimize the levels of three factors: the amounts of hydroxide, silicate, and metakaolin. In addition, the effect of Na or K as the charge-balancing cation was studied. Empirical models were fitted to the experimental data using multiple linear regression. The significance of the models was confirmed by means of analysis of variance. Optimal NH₄ ⁺ removal efficiency was achieved when the amounts of hydroxide and silicate were maximized, the amount of metakaolin was minimized, and Na-based reagents were used. These trends are most likely a result of optimized conversion of metakaolin into MK-GP.     

Visualization of a pharmaceutical unit operation: wet granulation

Recent developments in the field of process engineering and manufacturing sciences enable a new level of process understanding. However, extracting this understanding from increasing amounts of information is challenging. The aim of this study was to create a process vector from a model process describing all relevant information and, by that means, create a tool for combining and visualizing this information. Physical (impeller torque and temperature) and chemical (near-infrared spectroscopy) information from a small-scale high-shear granulation was used in the process vector. The vectors created were visualized by two different methods: principal component analysis (PCA) and the self-organizing map (SOM). None of the individual measurement techniques were able to describe the state of the process alone, although they provided important information about the process. By combining the data and visualizing it, an overview could be achieved. The SOM approach had two advantages over the PCA: it presented the results in terms of the original variables and enabled the analysis of nonlinear responses. However, both visualization methods could be used to describe the progress of the process and to increase the level of process understanding.     

Application of distance sampling techniques for diving ducks on Lake St. Clair and western Lake Erie

Lake St. Clair and western Lake Erie are important migration staging areas for diving ducks including canvasbacks (Aythya valisineria), redheads (Aythya americana), and lesser and greater scaup (Aythya affinis and Aythya marila). Starting in 1983, the Michigan Department of Natural Resources (MDNR) attempted to census diving ducks on the United States portion of Lake St. Clair throughout autumn migration; however, in 2010 the MDNR expanded the traditionally surveyed area to include all of Lake St. Clair and a portion of western Lake Erie. The idea of achieving a census over the expanded study area was unrealistic, and instead distance sampling techniques were adopted in an effort to generate statistically valid estimates of detection probabilities and abundances for diving ducks during spring and autumn migration. We found distance sampling techniques to be a viable option for estimating diving duck abundance as long as flock size is accounted for as a covariate affecting the detection function. Diving ducks were generally more abundant on our study area during autumn migration with a mean of 306,327 ducks/survey (SE = 40,729) compared to an average spring abundance of 91,053 ducks/survey (SE = 19,175). Peak abundance occurred on 20 November 2012 with an estimated 596,335 diving ducks on Lake St. Clair and western Lake Erie. Ultimately, our methodology could be used to establish long-term, standardized data collection techniques and applied to conservation planning for waterfowl in the Great Lakes region.     

Randomised trial of laparoscopic versus open cholecystectomy for acute and gangrenous cholecystitis

BACKGROUND: Laparoscopic cholecystectomy (LC) has become the treatment of choice for elective cholecystectomy, but controversy persists over use of this approach in the treatment of acute cholecystitis. We undertook a randomised comparison of the safety and outcome of LC and open cholecystectomy (OC) in patients with acute cholecystitis. METHODS: 63 of 68 consecutive patients who met criteria for acute cholecystitis were randomly assigned OC (31 patients) or LC (32 patients). The primary endpoints were hospital mortality and morbidity, length of hospital stay, and length of sick leave from work. Analysis was by intention to treat. Suspected bile-duct stones were investigated by preoperative endoscopic retrograde cholangiography (LC group) or intraoperative cholangiography (OC group). FINDINGS: The two randomised groups were similar in demographic, physical, and clinical characteristics. 48% of the patients in the OC group and 59% in the LC group were older than 60 years. 13 patients in each group had gangrene or empyema, and one in each group had perforation of the gallbladder causing diffuse peritonitis. Five (16%) patients in the LC group required conversion to OC, in most because severe inflammation distorted the anatomy of Calot's triangle. There were no deaths or bile-duct lesions in either group, but the postoperative complication rate was significantly (p=0.0048) higher in the OC than in the LC group: seven (23%) patients had major and six (19%) minor complications after OC, whereas only one (3%) minor complication occurred after LC. The postoperative hospital stay was significantly shorter in the LC than the OC group (median 4 [IQR 2-5] vs 6 [5-8] days; p=0.0063). Mean length of sick leave was shorter in the LC group (13.9 vs 30.1 days; 95% CI for difference 10.9-21.7). INTERPRETATION: Even though LC for acute and gangrenous cholecystitis is technically demanding, in experienced hands it is safe and effective. It does not increase the mortality rate, and the morbidity rate seems to be even lower than that in OC. However, a moderately high conversion rate must be accepted.     

Acute rejection of porcine small bowel allograft. An extended histological scoring system

Using nonimmunosuppressed piglet small bowel grafts, we performed a detailed histological study on acute rejection and analyzed altogether 45 different histological parameters throughout the bowel wall, in 10 allografts and 6 autografts. Heterotopic grafts were followed by full-thickness biopsies every other day beginning on the 3rd day after transplantation. The parameters were scored from 0 to 3 according to the severity of the change and the values of every variable were compared statistically between the 2 groups. The earliest significant changes, beginning on days 3-5, were infiltration of inflammatory cells and pyroninophilia among these cells in lamina propria; edema, fibrosis, and inflammation in submucosa and muscularis; vacuolar degeneration of myocytes; and endothelial and intimal changes in vessels. Villous blunting and cuboidal epithelium were the other early markers. On day 7, the epithelial and vascular changes became most significant. We want to emphasize especially the vascular parameters: endothelial swelling and proliferation, intimal thickening, intramural inflammation, and obliteration of the lumen. The dilatation of lymph vessels and changes of Peyer's patches had no value in the estimation of rejection. All allografts became necrotic by day 11 after transplantation.     

The effect of dietary forage to concentrate ratio and forage type on milk fatty acid composition and milk fat globule size of lactating cows

We examined the effects of 2 grass silage-based diets differing in forage:concentrate (FC) ratio and those of a red clover silage-based diet on intake, milk production, ruminal fatty acid (FA) biohydrogenation, milk FA composition, and milk fat globule (MFG) size distribution. Ten multiparous Nordic Red cows received the following treatments: grass silage-based diets containing high (70:30, HG) or low (30:70, LG) FC ratio or a red clover silage-based diet with an FC ratio of 50:50 (RC) on a dry matter basis. Determinations of MFG were performed from fresh milk samples without addition of EDTA so the results of fat globules >1 µm in diameter are emphasized instead of the entire globule population. Lower FC ratio in grass silage-based diets increased milk production with no effect on daily fat yield, leading to 13% lower milk fat concentration. The effect of FC ratio on MFG size was moderate. It did not affect the volume-weighted diameter in grass silage-based diets, although LG lowered the volume-surface diameter of MFG in the size class >1 µm compared with HG. Compared with HG, feeding LG moderately decreased the biohydrogenation of 18:2n-6, leading to a higher level of polyunsaturated fatty acids in milk fat. Feeding RC lowered milk fat concentration and daily milk fat yield compared with grass silage-based diets. The volume-weighted diameter of MFG in the size class >1 µm was smaller in RC milk compared with grass silage-based diets. Feeding RC increased the flow of 18:3n-3 at the omasum by 2.4-fold and decreased the apparent ruminal 18:3n-3 biohydrogenation compared with grass silage-based diets despite similar intake of 18:3n-3. It also resulted in the lowest amount of saturated FA and the highest amounts of cis-9 18:1, 18:3n-3, and polyunsaturated FA in milk. In conclusion, LG decreased milk fat content and induced minor changes in MFG size distribution compared with HG, whereas RC lowered milk fat production, altered milk FA composition to nutritionally more beneficial direction, and led to smaller MFG compared with grass silage-based diets.     

Impaired absorption of cholesterol and bile acids in patients with an ileoanal anastomosis

BACKGROUND: No data exist on cholesterol absorption in patients with an ileoanal anastomosis (IAA). AIMS: To study cholesterol absorption and its effects on cholesterol and bile acid metabolism in patients with an IAA. PATIENTS AND METHODS: Cholesterol absorption, and serum, biliary, and faecal lipids were studied in 24 patients with an IAA and 20 controls. RESULTS: Fractional cholesterol absorption was significantly lower in the patients (36% versus 47% in controls). Surprisingly, the calculated intestinal influx of endogenous cholesterol was reduced so that the absolute absorption of cholesterol was decreased; elimination of cholesterol as faecal neutral steroids remained normal. Thus, the slightly increased cholesterol synthesis was mainly due to increased faecal bile acid excretion, which, in turn, was associated with reduced absorption and biliary secretion of bile acids. Serum total and low density lipoprotein (LDL) cholesterol and LDL triglycerides were lower in the patients. Molar percentage and saturation index of biliary cholesterol were slightly higher in patients with an IAA. Proportions of secondary bile acids in bile and faeces were diminished, and faecal unidentified bile acids were higher in patients. CONCLUSIONS: Cholesterol absorption is significantly impaired in patients with an IAA, and is closely related to changes in serum and biliary lipids observed in these patients.     

Is scientists' publishing behaviour rewardseeking?

The use of bibliometric indicators in research evaluation makes many hidden assumptions about scientists' publishing habits. This paper tests an assumption that scientists are reward oriented and attempt to publish in as prestigious channels as possible, seeking an optimal level in the hierarchy of publications. The data are based on interviews with teaching and research personnel in four university departments in the fields of zoology, biomedicine, and automation and control technology. The author concludes that in all studied fields scientists placed equal emphasis on the reward and communication functions of publishing. The actual publishing behaviour of biomedical scientists, nevertheless, accorded best with the assumption of seeking an optimal level of publishing in terms of prestige. By contrast, in zoology and technical fields, local and field-related publishing habits appeared strong.     

Experimental verification of analytical model for high impedance surfaces

A simple yet accurate analytical model for a high impedance surface comprising an array of capacitive patches over a grounded dielectric slab is experimentally verified. The results are compared for the oblique incidence reflection phase obtained with the analytical model and commercial simulation software with the results of free-space measurements. It is shown that the analytical and simulation results are in very good agreement with the experimental results. To the authors? knowledge, this is the first time the results of the analytical model in question have been experimentally verified.