We tested whether seal location at iliac crest (IC) or upper abdomen (UA), before and during lower body negative pressure (LBNP), would affect thoracic electrical impedance, hepatic blood flow, and central cardiovascular responses to LBNP. After 30 min of supine rest, LBNP at -40 mmHg was applied for 15 min, either at IC or UA, in 14 healthy males. Plasma density and indocyanine green concentrations assessed plasma volume changes and hepatic perfusion. With both sealing types, LBNP-induced effects remained unchanged for mean arterial pressure (-3.0±1.1 mm Hg), cardiac output (-1.0 l min-1), and plasma volume (-11 %). Heart rate was greater during UA (80.6±3.3 bpm) than IC (76.0±2.5 bpm) (p<0.01) and thoracic impedance increased more using UA (3.2±0.2 Ω) than IC (1.8±0.2 Ω) (p<0.0001). Furthermore, during supine rest, UA was accompanied by lower thoracic impedance (26.9±1.1 vs 29.0±0.8 Ω , p<0.001) and hepatic perfusion (1.6 vs 1.8 l.min-1, p<0.05) compared to IC. The data suggest that the reduction in central blood volume in response to LBNP depends on location of the applied seal. The sealing in itself altered blood volume distribution and hepatic perfusion in supine resting humans. Finally, application of LBNP with the seal at the upper abdomen induced a markedly larger reduction in central blood volume and greater increases in heart rate than when the seal was located at the iliac crest., N. Goswami ... [et al.]., and Obsahuje seznam literatury
To explore the cause of difference in photosynthetic performance between different cultivars of crops, leaf net photosynt rate (PN) and photosystem 2 (PS2) photochemical efficiency (Fv/Fm), apparent quantum yield of carbon assimilation (φc), electron transport rate, photophosphorylation activity, etc. were measured in two soybean cultivars, Heinong 42 and Heinong 37. At pod setting and filling, significant differences in PN between them were observed. The former with a higher PN (from 7 to 38 %) had a significantly higher leaf thickness, leaf dry mass/area (LMA), chlorophyll content, soluble protein content, apparent quantum yield of electron transport through PS2 (φe), carboxylation efficiency (CE), and ribulose-1,5-bisphosphate carboxylase (RuBPC) activity. The significantly higher PN of Heinong 42 is mainly due to its higher content and activity of RuBPC. and Hua Jiang, Da-Quan Xu.
The present nuclear and cell body diameter measurements demonstrated size differences of the approximate cell space estimate occupied by the cell nucleus during the cell differentiation in lymphocytic, granulocytic and erythroid cell lineages. These lineages were used as convenient models because all differentiation steps were easily identified and accessible in diagnostic peripheral blood or bone marrow smears of blood donors (BDs), patients suffering from chronic lymphocytic leukemia (CLL), patients with chronic myeloid leukemia (CML) and refractory anemia (RA) of the myelodysplastic syndrome (MDS). The cell space occupied by the nucleus was constant and did not change during the cell differentiation in the lymphocytic cell lineages of BDs and CLL patients despite the decreased cell size. In contrary, the cell space occupied by the nucleus markedly decreased in differentiating cells of granulocytic and erythroid lineages of patients suffering from CML. In the erythroid cell lineage in patients with RA of MDS the small reduction of the cell space occupied by the nucleus during the differentiation was not significant. The measurements also indicated that in progenitor cells of all studied cell lineages nuclei occupied more than 70 % of the cell space. Thus, the nucleus-cytoplasmic morphological and functional equilibrium appeared to be characteristic for each differentiation step and each specific cell lineage., Karel Smetana, Hana Klamová, Dana Mikulenková, Jaroslav Čermák, Petra Otevřelová, Josef Karban, Marek Trněný., and Obsahuje bibliografii
Laboratory rats were exposed to the inhalation of dust from an agglomeration unit which is the greatest contributor to dust pollution in the vicinity of a mercury producing plant. The exposure lasted for 6 months (4 hours daily, 5 days per week), the concentration of aerosol in the chamber was 10 mg.m-3. After finishing the exposure, the animals were examined and compared with the controls which were held under standard laboratory conditions. The number of alveolar macrophages was highly elevated (P<0.001) in the exposed animals, Mg24 ATPase activity in the heart muscle was decreased. The alanine aminotransferase activity in the serum was not changed, the aspartate aminotransferase was slightly enhanced. No differences in the frequency of abnormal sperm and in the frequency of polychromatic erythrocytes in bone marrow were detected.
Male Wistar rats adapted to a light/dark cycle (LD) 12:12 h were exposed in the darkness to a single dose of 14.35 Gy gamma rays on the head with the body shielded. Irradiated and sham-irradiated rats were kept again in the 12 h LD cycle with a free access to food and water till the analysis performed in the darkness. Pineal N-acetyltransferase activity and melatonin content, the serum concentration of the melatonin, corticosterone, thyrotropin and thyroid hormones were determined. N-acetyltransferase activity was lower 2-24 h after irradiation non-significantly whereas between 3-10 days it did not differ from the controls. Radiation decreased the pineal melatonin content and its serum concentration 2 h after exposure and increased them significantly 1-3 days after irradiation. No changes in melatonin levels were found on postirradiation days 5-10. The corticosterone concentration was increased 2 h after exposure only. Local head irradiation changed neither thyrotropin nor thyroid hormone levels.
The liver fluke Clonorchis sinensis (Digenea) is a high-risk parasite that causes serious diseases such as cirrhosis, carcinogenic liver damage and clonorchiasis in East Asia. This study was conducted to evaluate the relationship between stress/endocrine hormones and inflammation induced by infection as well as the expression of heat shock proteins (hsp-27, hsp-90), cox-2 and cytokines in the livers of hamsters infected with C. sinensis. The average body weight of infected hamsters decreased up to 25% compared with that of the control group, and bile duct hyperplasia with inflammation, liver fibrosis and hepatic necrosis were observed in C. sinensis-infected livers. The expression of hsp-27, hsp-90, and cox-2 was significantly increased in the livers of C. sinensis-infected hamsters compared with the control group. Moreover, the expression levels of inflammatory cytokines (IL-1β, IL-2, TGF-β2 and IFN-α1) were markedly increased in the livers of the infected group compared with those of the control group. Consistently, plasma IL-3 and IL-6 levels gradually increased during the infection period, and the concentration levels of testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), corticosterone, and adrenocorticotropic hormone (ACTH) in C. sinensis-infected hamsters increased over 25%, compared with those of the uninfected normal group. These results demonstrate that C. sinensis infection may increase the expression of hsp27, hsp90 and cox-2 as well as it may cause periductal fibrosis, chronic inflammation and hepatic necrosis in the liver. Furthermore, the results indicate that C. sinensis infection induces not only stress-induced hormone imbalance but also the sustained secretion of inflammatory cytokines through chronic stress/stimuli.
In the study presented, different hybrid model approaches are proposed for reservoir inflow modeling from the meteorological data (monthly precipitation, one-month-ahead precipitation and monthly mean temperature data) by the combined use of discrete wavelet transform (DWT) and different black box techniques. Multiple linear regression (MLR), feed forward neural networks (FFNN) and least square support vector machines (LSSVM) were considered as the black box methods. In the modeling strategy, meteorological input data were decomposed into wavelet sub-time series at three resolution levels and ineffective sub-time series were eliminated by Mallows’ Cp based all possible regression method. As a result of all possible regression analyses, 2-months mode of time series of monthly temperature (D1_Tt), 8-months mode of time series (D3_Tt) of monthly temperature and approximation mode of time series (A3_Tt) of monthly temperature were eliminated. Remained effective sub-time series were used as the inputs of MLR, FFNN and LSSVM. When the performances of the training and testing periods were compared, it was observed that the DWTFFNN conjunction model has better results in terms of mean square errors (MSE) and determination coefficients (R2 ) statistics. The discrete wavelet transform approach also increased the accuracy of multiple linear regression and least squares support vector machines.