Patients with obesity and type 2 diabetes often display high levels of the anti-diabetic factor fibroblast growth factor-21 (FGF21), suggesting that the overproduction of FGF21 may result from increased adiposity in an attempt by white adipose tissue (WAT) to counteract insulin resistance. However, the production of FGF21 diabetes in the absence of WAT has not been examined. In this study, we investigated the effects of lipodystrophy in A-ZIP F-1 mice on FGF21 production in relation to diabetes. A-ZIP F-1 mice displayed high FGF21 plasma levels resulting from enhanced FGF21 mRNA expression in the liver. Concomitant enhancement of FGF21 receptor (FGFR1) and glucose transporter 1 (GLUT-1) mRNA expression was observed in the muscles of A-ZIP F-1 mice. Furthermore, the activation of hypothalamic NPY and AgRP mRNA expression positively correlated with plasma levels of FGF21 but not active ghrelin. Our study demonstrates that an increased FGF21 plasma level in lipodystrophic A-ZIP F-1 mice results mainly from up-regulated liver production but does not suffice to overcome the lipodystrophy-induced severe type 2-diabetes and insulin resistance in the liver linked to the augmented liver fat deposition., A. Špolcová, M. Holubová, B. Mikulášková, V. Nagelová, A. Štofková, Z. Lacinová, J. Jurčovičová, M. Haluzík, L. Maletínská, B. Železná., and Obsahuje bibliografii
This study was designed to investigate histological changes in skin tissue accompanying immobilization-induced hypersensitivity. Changes in mechanical sensitivity, epidermal thickness, and peripheral nerve profiles in the upper dermis were examined in glabrous skin of rat hind paw after 1, 2, and 4 weeks of ankle joint immobilization by plaster casts. Induction of mechanical hypersensitivity was confirmed after 2 and 4 weeks of joint immobilization. Epidermal thinning and increase in peripheral nerve profiles were observed in skin tissues in immobilized rats. The time course of epidermal thinning and increase in peripheral nerve profiles were similar closely to that of hypersensitivity, with significant differences between the immobilized and control rats after 2 weeks of immobilization, which became even more remarkable at 4 weeks of immobilization. These findings suggest that joint immobilization by cast induces epidermal thinning and increases peripheral nerve profiles in the upper dermis and that these changes might be partly responsible for immobilization-induced hypersensitivity., J. Nakano, ... [et al.]., and Obsahuje seznam literatury
In comparison with its wild type (WT), the transgenic (TG) rice with silenced OsBP-73 gene had significantly lower plant height, grain number per panicle, and leaf net photosynthetic rate (PN). Also, the TG rice showed significantly lower chlorophyll (Chl), ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO), RuBPCO activase, and RuBP contents, photosystem 2 (PS2) photochemical efficiency (Fv/Fm and ΔF/Fm'), apparent quantum yield of carbon assimilation (Φc), carboxylation efficiency (CE), photosynthetic electron transport and photophosphorylation rates as well as sucrose phosphate synthase activity, but higher intercellular CO2 concentration, sucrose, fructose, and glycerate 3-phosphate contents, and non-photochemical quenching of Chl fluorescence (NPQ). Thus the decreased PN in the TG rice leaves is related to both RuBP carboxylation and RuBP regeneration limitations, and the latter is a predominant limitation to photosynthesis. and Y. Chen, D.-Q. Xu.
The study was designed to prove the hypothesis that lipopolysaccharide (LPS)-induced fever elicits the changes in surfactant specific proteins, potentially related to thermal tachypnea. In adult rats fever was induced by intraperitoneal administration of LPS at a dose 100 μg/kg of body weight; control group received saline. Respiratory parameters, arterial blood gases and pH and colonic body temperature (BT) were recorded. Five hours later, surfactant proteins (SP) A, B, C and D were evaluated in bronchoalveolar lavage fluid (BALF) and lung tissue (LT). LPS evoked monophasic thermic response (at 300 min 38.7±0.2 vs. 36.4±0.3 °C, P<0.05) and an increase in minute ventilation due to changes in breathing rate and tidal volume. LPS-instilled animals had higher levels of SP-A and SP-D in LT (P<0.05 and 0.01), and higher SP-D in BALF (P<0.01) than controls. SP-B increased in LT and SP-C in BALF of animals with LPS (both P0.05 vs. controls). The changes in all surfactant specific proteins are present in LPS-induced fever. Alterations of proteins related to local immune mechanisms (SP-A, SP-D) are probably a part of general inflammatory response to pyrogen. Changes in proteins related to surface activity (SP-B and SP-C) might reflect the effort of the body to stabilize the lungs in thermal challenge., M. Kolomaznik, I. Zila, J. Kopincova, D. Mokra, A. Calkovska., and Obsahuje bibliografii
Photosynthetic traits of two-year-old Japanese larch seedlings (Larix kaempferi Carr.) grown at elevated CO2 concentrations were studied in relation to structural changes in the needles. Seedlings were grown at two CO2 concentrations, 360 (AC) and 720 (EC) μmol mol-1 at high and low nutrient supply rates, high N (HN) and low N (LN). The photosynthetic capacity fell significantly in EC+LN, but increased significantly in EC+HN. Since the mesophyll surface area exposed to intercellular space per unit leaf area (Ames/A) is correlated with the photosynthetic rate, we measured Ames/A for larch needles growing in EC. Changes of Ames/A in both EC+HN and EC+LN were very similar to the changes in photosynthetic capacity. This suggests that the changes of Ames/A in EC probably caused the changes in the photosynthetic capacity. The changes of Ames/A in EC were attributed to changes in the mesophyll cell size and mesophyll cell number. The photosynthetic capacity in EC can be explained by taking morphological and structural adaptations into account as well as biochemical factors. and N. Eguchi ... [et al.].
Net rates of photosynthesis (PN) saturated by irradiance of >500 μmol m-2 s-1 (PAR) significantly decreased in water-stressed potato (Solanum tuberosum L. cv. Kufri Sindhuri) plants. The quantum yield of photochemical energy conversion (Fv/Fm), relative electron transport rate (ETR), and photochemical quenching (Qp) exhibited a parallel decline at high irradiance. A slight decrease in relative water content (RWC) was accompanied by a drastic decline in leaf water potential (Ψw) from -0.2 to -1.0 MPa. Dehydrated leaves showed an increase in the amount of total soluble sugars per unit leaf area which inhibited the photosynthesis in a feedback manner. After rewatering, PN and Fv/Fm were restored to the values of control plants within 24 h, and the restoration was accompanied by a proportionate lowering of content of total soluble sugars in the leaves. and P. S. Basu, Ashoo Sharma, N. P. Sukumaran.
The role of cortico-tectal pathways in auditory signal processing was studied in anesthetized rats by comparing the extracellular single unit activity in the inferior colliculus (IC) before and after functional ablation of the auditory cortex (AC) by tetrodotoxin (TTX). The responses of several IC neurons to sound stimuli were simultaneously recorded with a 16-channel electrode probe introduced into the IC. Click-evoked middle latency responses (MLR) recorded from the AC were suppressed for several hours after TTX injection. During AC inactivation the firing rate of IC neurons increased (40 % of neurons), decreased (44 %) or did not change (16 %) in comparison with control conditions. In several IC neurons, TTX injection resulted in alterations in the shape of the rate-level functions. Response thresholds, tuning properties and the type of discharge pattern of IC neurons were not altered during AC inactivation. However, in one-third of the neurons, the initial part of the response was less altered than the later, sustained part. In two-thirds of neuronal pairs, functional decortication resulted in a change in the cross-correlation coefficient. The results reveal the complex changes that appear in IC neuronal activity after functional ablation of the ipsilateral auditory cortex., J. Popelář, F. C. Nwabueze-Ogbo, J. Syka., and Obsahuje bibliografii
Oxidative stress may be caused by an increased rate of ATP resynthesis during physical exercise. The aim of this study was to compare changes in the prooxidant-antioxidant state of blood plasma between men and women after maximal-intensity exercise, and to assess the relationship between these changes and the value of the maximal oxygen uptake (VO2max) as well as between these changes and the value of post-exercise disruptions in acid-base balance. Study participants comprised 10 women (20.7±0.5 years) and 10 men (22.3±0.5 years) who were physically active but did no t engage in competitive sports training. VO2max was determined via treadmill incremental test (VO2max relative to body mass: 44.48±1.21 ml/kg/min and 59.16±1.55 ml/kg/min for women and men, respectively). The level of acid-base balance indicators (ABB), lactate concentration (La-), the level of total oxidative status (TOS), the level of total antioxidative capacity (TAC), an d uric acid (UA) concentration were measured before and after the test. An oxidative stress indicator (OSI) was also calculated. Men showed a significant post-exercise increase in the level of TOS and OSI, while women showed a significant post-exercise increase in the level of TAC. Post-exercise changes in UA concentration were insignificant. Post-exercise changes in TOC in men depended on the absolute values of VO2max , on VO2max/LBM, and on post-exercise changes in La- concentration., M. Wiecek, M. Maciejczyk, J. Szymura, Z. Szygula., and Obsahuje bibliografii
In experiments on 51 healthy anaesthetized and paralyzed rabbits the changes in parameters of mechanics of breathing during high frequency jet ventilation (HFJV) were determined and the mechanisms responsible for these changes were investigated. In the first series of experiments with two groups of animals ventilated by HFJV with relative inspiratory time ti = 0.5 and ti = 0.7 airway resistance (Raw) after 5 h of HFJV in the ti = 0.5 group increased from 1.14±0.05 to 2.31±0.09 kPa.l_1.s (P<0.001), in the ti = 0.7 group from 1.22±0.04 to 1.78±0.08 kPa.l-1.s (P<0.01). Dynamic compliance (Cdyn) decreased in the ti = 0.5 group from 0.041 ±0.004 to 0.017±0.001 l.kPa-1 (P<0.01) and in the ti = 0.7 group from 0.034± 0.003 to 0.022± 0.002 l.kPa-1 (P<0.01). In the second series of experiments a group of animals was ventilated by HFJV after cervical vagotomy. The deterioration of Raw and Cdyn was significantly reduced in vagotomized rabbits in comparison to the controls without vagotomy. Finally, the study of phospholipid content in bronchoalveolar lavage fluid revealed no significant differences after 5 h of artificial ventilation or spontaneous breathing. These data indicate that HFJV results in changes in the parameters of mechanics of breathing in healthy lungs, which may be attenuated, but not fully eliminated, by bilateral cervical vagotomy. The decrease in Cdyn and increase in Raw are probably not due to changes in the pulmonary surfactant content.
Peripheral blood monocytes, which serve as precursors for tissue macrophages and dendritic cells (DC), play a key role in the immune response to kidney allograft, reparation processes and homeostasis regulation. In this prospective study, we used multicolor flow cytometry to monitor the phenotypic patterns of peripheral monocytes in subjects with uncomplicated outcomes and those with acute rejection. We found a reciprocal increase in the proportion of "classical monocytes" (CD14+CD16-) along with a decline in pro-inflammatory "intermediary" (CD14+CD16+) and "non-classical" (CD14lowCD16+) monocytes in subjects with normal outcomes. In subjects with acute rejection, we observed no reduction in "intermediary" monocytes and no increase in "classical" monocytes. Patients with uncomplicated outcomes exhibited downregulated HLA-DR in all three monocyte subpopulations. However, non-classical monocytes were unaffected in subjects with acute rejection. Expression of CD47 was downregulated after transplantation, while patients with antibody-mediated rejection and donor-specific antibodies showed higher pre-transplant values. In monocytes isolated at the time of biopsy, CD47 expression was higher in individuals with acute rejection compared to patients with normal outcomes one year post-transplant. Expression of CD209 (DC-SIGN) and the proportion of CD163+CD206+ subpopulations were upregulated during the first week after kidney transplantation. CD209 was also upregulated in samples taken on the day of biopsy confirming acute rejection. Our data demonstrate that kidney allograft transplantation is associated with phenotypic changes in peripheral blood monocytes during acute rejection., Veronika Švachová, Lenka Krupičková, Marek Novotný, Martina Fialová, Kristýna Mezerová, Eva Čečrdlova, Věra Lánská, Antonij Slavčev, Ondřej Viklický, Ilja Stříž., and Obsahuje bibliografii