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1.
Our previous study showed that pretreatment with 5-hydroxymethyl-2-furfural (5-HMF) led to protection against hypoxic injury
via a p-ERK-mediated pathway in vitro. Whether the protection of 5-HMF against hypoxia is effective in vivo is unknown. The
present study is aimed to verify the role of 5-HMF in acute hypobaric hypoxia using Kunming mice as an in vivo model and further
investigate the underlying mechanisms. Mice pretreated with or without 5-HMF for 1 h were exposed to acute hypobaric hypoxic
condition for 6 h and then the survival time, the survival rate, the permeability of blood–brain barrier (BBB), the histological
analysis in hippocampus and cortex, and the phosphorylation level of mitogen-activated protein kinases (ERK, JNK, and p38)
were investigated. The results showed that 5-HMF significantly increased the survival time and the survival rate of mice.
Accordingly, pretreatment with 5-HMF markedly attenuated acute hypobaric hypoxia-induced permeability of BBB (P < 0.01). In addition, the cellular damage extent of the hippocampus and the cortex induced by hypoxia for 6 h was also attenuated
by pretreatment with 5-HMF, especially in the hippocampus CA1 region. Furthermore, the activation of ERK rather than JNK and
p38 was involved in the protection of 5-HMF against acute hypobaric hypoxia. In summary, 5-HMF enhanced the survival capability
of mice and decreased acute hypoxic damage to the brain, which may be associated with the effects on BBB and p-ERK. 相似文献
2.
Manouchehr Nakhjavani Afsaneh Morteza Leila Khajeali Alireza Esteghamati Omid Khalilzadeh Firouzeh Asgarani Tiago F. Outeiro 《Cell stress & chaperones》2010,15(6):959-964
The evolutionary conserved family of heat shock proteins (HSP) is responsible for protecting cells against different types
of stress, including oxidative stress. Although the levels of HSPs can be readily measured in blood serum, the levels of HSP70
in patients with different durations of diabetes have not been studied before. We quantified serum HSP70 levels in a healthy
control group (n = 36) and two groups of type 2 diabetic patients, defined as newly diagnosed diabetes (n = 36) and patients with diabetes duration of more than 5 years (n = 37). The clinical characteristics and biochemical parameters were evaluated in the studied population. We found that serum
HSP70 levels were significantly higher in patients with diabetes when compared with controls (p < 0.001) and it was higher in patients with disease for more than 5 years than in newly diagnosed patients (p < 0.001). Serum HSP70 was inversely correlated with fasting blood sugar in patients with diabetes for more than 5 years (r = −0.500, p = 0.002), positively correlated with the history of hypertension in newly diagnosed patients (p < 0.001), and positively correlated with age in patients with diabetes (r = 0.531, p = 0.001). Serum level of HSP70 is significantly higher in patients with diabetes and correlates with the duration of disease.
Higher HSP70 in prolonged diabetes versus newly diagnosed diabetes may be an indicator of metabolic derangement in the course
of diabetes. 相似文献
3.
Summary. Heat shock proteins (HSPs) are synthesised by cells subsequent to a stress exposure and are known to confer protection to
the cell in response to a second challenge. HSP induction and decay are correlated to thermotolerance and may therefore be
used as a biomarker of thermal history. The current study tested the temperature-dependent nature of the heat shock response
and characterised its time profile of induction. Whole blood from 6 healthy males (Age: 26 ± (SD) 2 yrs; Body mass 74.2 ±
3.8 kgs; VO2max: 49.1 ± 4.0 ml·kg−1·min−1) were isolated and exposed to in vitro heat shock (HS) at 37, 38, 39, 40, and 41 °C for a period of 90 min. After HS the
temperature was returned to 37 °C and intracellular HSP70 was quantified from the leukocytes at 0, 2, 4, and 6 h after heat
treatment. The concentration of HSP70 was not different between temperatures (P > 0.05), but the time-profile of HSP70 synthesis appeared temperature-dependent. At control (37 °C) and lower temperatures
(38–39 °C) the mean HSP70 concentration increased up to 4 h post HS (P < 0.05) and then returned towards baseline values by 6 h post HS. With in vitro hyperthermic conditions (40–41 °C), the time-profile
was characterised by a sharp rise in HSP70 levels immediately after treatment (P < 0.05 for 40 °C at 0 h), followed by a progressive decline over time. The results suggest a temperature-dependent time-profile
of HSP70 synthesis. In addition, the temperature at which HSP70 is inducted might be lower than 37 °C. 相似文献
4.
Judit Kocsis Balázs Madaras Éva Katalin Tóth George Füst Zoltán Prohászka 《Cell stress & chaperones》2010,15(2):143-151
Many findings indicate that measuring the serum concentration of soluble 70-kD heat shock protein (soluble HSP70) may provide
important information in cardiovascular, inflammatory, and pregnancy-related diseases; however, only scarce data are available
in cancer. Therefore, using a commercial ELISA kit, we measured soluble HSP70 concentration in the sera of 179 patients with
colorectal cancer. We investigated the relationship between soluble HSP70 concentration and mortality, during 33.0 (24.4–44.0) months
long follow-up. High (>1.65 pg/ml, median concentration) soluble HSP70 level was a significant (hazard ratio: 1.88 (1.20–2.96,
p = 0.005) predictor of mortality during the follow-up period. When we compared the soluble HSP70 levels in patients with non-resected
primary tumors as compared to those who were recruited into the study 4–6 weeks after the tumor resection they were found
to be significantly (p = 0.020) higher in the former group. Since the patients with non-resected primary tumors had also distant metastasis and
died early, we limited the further analysis to 142 patients with no distant metastasis at the beginning of the follow-up.
This association remained significant even after multiple Cox-regression analysis had been performed to adjust the data for
age and sex (p = 0.028); age, sex, and TNM-T stage (p = 0.041); age, sex, and TNM-N stage (p = 0.021); age, sex, and histological grade (p = 0.023); or age, sex, and tumor localization (p = 0.029). Further analysis showed that the significant association between high HSP70 levels and poor survival is in the
strongest in the group of <70-year-old female patients (HR: 5.52 (2.02-15.15), p = 0.001), as well as in those who were in a less advanced stage of the disease at baseline. These novel findings indicate
that the serum level of soluble HSP70 might prove a useful, stage-independent prognostic marker in colorectal cancer without
distant metastasis. 相似文献
5.
Hou C Changchun H Zhao H Haijin Z Li W Wenjun L Liang Z Zhenyu L Zhang D Dan Z Liu L Laiyu L Tong W Wancheng T Cai SX Shao-Xi C Zou F Fei Z 《Cell stress & chaperones》2011,16(6):663-671
Damage-associated molecular pattern molecules such as high-mobility group box 1 protein (HMGB1) and heat shock protein 70
(HSP70) have been implicated in the pathogenesis of asthma. The aim of our study was to examine the induced sputum and plasma
concentrations of HSP70 in asthmatic patients to determine their relationship with airway obstruction. Thirty-four healthy
controls and 56 patients with persistent bronchial asthma matched for gender and age were enrolled in this study. Spirometry
measurements were performed before sputum induction. HSP70 levels in induced sputum and plasma were measured using the ELISA
Kit. Sputum and plasma concentrations of HSP70 in asthmatics patients were significantly higher than that in control subjects
(sputum, (0.88 ng/ml (0.27–1.88 ng/ml) versus 0.42 ng/ml (0.18–0.85 ng/ml), p < 0.001); plasma, (0.46 ng/ml (0.20–0.98 ng/ml) versus 0.14 ng/ml (0.11–0.37 ng/ml), p < 0.001) and were significantly negatively correlated with forced expiratory volume in 1 s (FEV1), FEV1 (percent predicted),
and FEV1/FVC in all 90 participants and 56 patients with asthma. There were no significant differences in HSP70 levels between
patients with eosinophilic and non-eosinophilic asthma. HSP70 levels in plasma were positively correlated with neutrophil
count, and HSP70 levels in induced sputum were positively correlated with lymphocyte count. In multivariate analysis, independent
predictors of sputum HSP70 were diseases and disease severity but not smoking, age, or gender, and independent predictors
of plasma HSP70 were also diseases and disease severity. In conclusion, this study indicates that induced sputum and plasma
HSP70 could serve as a useful marker for assessing the degree of airway obstruction in patients with asthma. However, further
investigation is needed to establish the role of circulating and sputum HSP70 in the pathogenesis of asthma. 相似文献
6.
Data on zinc concentration in the human body may be used to interpret the results obtained in cases of chronic and acute poisonings
with zinc compounds, i.e., in clinical and forensic toxicology. In this paper, the concentrations of zinc in human tissues
and body fluids obtained from autopsy cases concerning non-poisoned people (n = 203), aged from 14 to 80 years, between 1995 and 2008, are presented. The following values were found by the flame atomic
absorption method (mean ± SD, median, range, in microgram per gram or microgram per milliliter): brain 10.3 ± 1.36, 10.2,
7.99–13.8 (n = 48); stomach 14.2 ± 3.63, 13.6, 8.00–22.5 (n = 71); intestines 15.7 ± 5.22, 15.8, 8.36–28.1 (n = 35); liver 39.6 ± 16.1, 36.6, 16.0–78.8 (n = 109); kidney 33.8 ± 10.1, 31.8, 16.4–60.9 (n = 93); lung 12.0 ± 3.88, 11.0, 6.13–18.7 (n = 26); spleen 14.7 ± 2.53, 14.6, 11.4–18.3 (n = 5); heart 26.5 ± 3.63, 26.7, 22.5–31.8 (n = 5); blood 6.81 ± 1.21, 7.00, 4.02–8.68 (n = 50); urine 0.69 ± 1.70, 0.60, 0.39–1.00 (n = 5), and bile 4.92 ± 1.64, 3.75, 3.20–7.09 (n = 9). The accuracy of the method was checked through the use of SRM Bovine Liver 1577b (certified: 127 ± 16 μg Zn/g, found:
117 ± 0.7 μg Zn/g (n = 6)). 相似文献
7.
Using the voltage/current clamp technique in the whole-cell configuration, we studied the role of the highly tetraethylammonium
(TEA) -sensitive component of integral potassium current in the generation of high-frequency tonic impulsation by rat retinal
ganglion cells (RGCs). Application of 0.5 mM TEA led to a decrease in the frequency of evoked tonic impulsation by RGCs by
63% (from 55 ± 10 sec–1 in the control to 26 ± 5 sec–1 in the presence of the blocker; n = 11). In this case, the duration of single action potentials at the level of 50% their amplitude increased by 64% (from
1.1 ± 0.1 to 1.8 ± 0.1 msec; n = 11), the rate of repolarization decreased by 54% (from −101 ± 9 to −46 ± 5 mV/msec; n = 11), and the amplitude of afterhyperpolarization dropped by 62% (from −16 ± 2 to −6 ± 2 mV; n = 11). Upon the action of 0.5 mM TEA, the amplitude of the integral potassium current in RGCs decreased; the current component
sensitive to the above blocker was equal to 0.41 ± 0.05 nA (n = 6), while the respective value in the control was 1.62 ± 0.14 nA (n = 12). Thus, a moderate (on average, by 25%) decrease in the amplitude of the above potassium current significantly influenced
the characteristics of impulse activity generated by RGCs. The TEA-sensitive component of the current was similar to the Kv3.1/Kv3.2
potassium current described earlier. The obtained data are indicative of the key role of the highly TEA-sensitive component
of the potassium current (passed probably via Kv3.1/Kv3 channels) in high-frequency tonic activity generated by RGCs. 相似文献
8.
9.
Gregorio Mentaberre Jorge Ramón López-Olvera Encarnación Casas-Díaz Laura Fernández-Sirera Ignasi Marco Santiago Lavín 《European Journal of Wildlife Research》2010,56(5):757-764
The physical capture of wild ungulates is performed for different purposes when anesthesia in field conditions is not possible
or advisable. The use of tranquilizers may contribute to improved welfare of captured animals. This study aimed to evaluate
the effect of azaperone and haloperidol on the stress response of Iberian ibex (Capra pyrenaica) through the evaluation of physiological, hematological, and serum biochemical parameters. Thirty-five Iberian ibexes were
drive-net captured and randomly injected with azaperone (0.52 ± 0.07 mg/kg intramuscularly (IM); n = 10), haloperidol (0.17 ± 0.04 mg/kg IM; n = 10), or saline (0.5 mL IM; n = 15) and physically restrained for 3 h. The variability of heart rate was lower in the azaperone-treated ibexes, suggesting
a calming effect, and erythrocyte and biochemical parameters indicated vasodilation, splenic sequestration, hemodilution,
improvement of renal perfusion, and a protective effect on muscle as a result of smooth muscle relaxation induced by azaperone.
Haloperidol showed poorer results, maybe due to insufficient dosage. These results support the suitability of using azaperone
in capture operations of Iberian ibex in order to reduce stress and prevent its adverse effects. 相似文献
10.
Casimiro-Lopes G de Oliveira-Junior AV Portella ES Lisboa PC Donangelo CM de Moura EG Koury JC 《Biological trace element research》2009,127(2):109-115
The purpose of this study was to compare plasma leptin, plasma zinc, and plasma copper levels and their relationship in trained
female and male judo athletes (n = 10 women; n = 8 men). Blood samples were obtained 24 h after training to measure plasma zinc, copper, and leptin levels. Subjects presented
similar values to age (22 ± 2 years old), body mass index (24 ± 1 kg/m2), plasma zinc (17.2 ± 2 μmol/L), copper (12.5 ± 2 μmol/L), and leptin (5.6 ± 1.3 μg/L). However, height, total body mass,
lean mass, fat mass, and sum of ten-skinfold thickness were higher in male than female. Plasma leptin was associated with
sum of ten skinfolds in male (r = 0.91; p < 0.001) and female athletes (r = 0.84; p < 0.003). Plasma zinc was associated with leptin in males (r = 0.82; p < 0.05) while copper was associated with plasma leptin in females (r = 0.66; p < 0.05). Our results suggest that young judo athletes lost sex-related differences in leptin levels. Plasma zinc, plasma
copper, and energy homeostasis may be involved in regulation of plasma leptin. 相似文献
11.
Yong-Yu Li Shuai Lu Kun Li Jia-Yan Feng Yan-Na Li Zhi-Rong Gao Chang-Jie Chen 《Cell stress & chaperones》2010,15(6):965-975
The objective of this study was to investigate the function of heat shock protein 60 (HSP60) on pancreatic tissues by applying
HSP60 small interfering RNA (siRNA) to reduce HSP60 expression. Rat pancreas was isolated and pancreatic tissue snips were
prepared, cultured, and stimulated with low and high concentrations of cerulein (10−11 and 10−5 mol/L) or lipopolysaccharide (LPS, 10 and 20 μg/mL). Before the stimulation and 1 and 4 h after the stimulation, the viability
and the level of trypsinogen activation peptide (TAP) in the tissue fragments were determined and the levels of tumor necrosis
factor-alpha (TNF-α) and interleukin 6 (IL-6) in the culture supernatants were measured. Real-time PCR and Western blotting
were used to evaluate the HSP60 mRNA and protein expression. After the administration of siRNA to inhibit HSP60 expression
in the isolated tissues, these injury parameters were measured and compared. The pancreatic tissues in the control (mock-interfering)
group showed a decreased viability to varying degrees after being stimulated with cerulein or LPS, and the levels of TAP,
TNF-α, and IL-6 increased significantly (p < 0.05) in the tissues and/or in the culture supernatant. The expressions of HSP60 mRNA and protein were raised moderately after
stimulating 1 h with low concentrations of cerulein or LPS, but decreased with high concentrations of the toxicants. In particular,
the expression of HSP60 protein was reduced significantly (p < 0.05) when the tissues were stimulated by the two toxicants for 4 h. In contrast, the tissue fragments in which HSP60 siRNA
was applied showed much lower tissue viability (p < 0.01) and higher levels of TNF-a, IL-6, and TAP (p < 0.01) in the tissues or culture supernatant after stimulating with the toxicants at the same dose and for the same time duration
as compared with those of the control groups (p < 0.05). The results indicated that both cerulein and LPS can induce injuries on isolated pancreatic tissues, but the induction
effects are dependent on the duration of the stimulation and on the concentrations of the toxicants. HSP60 siRNA reduces HSP60
expression and worsens the cerulein- or LPS-induced injuries on isolated pancreatic tissues, suggesting that HSP60 has a protective
effect on pancreatic tissues against these toxicants. 相似文献
12.
Kimotsuki T Niwa N Hicks MN Dunne M Cobbe SM Watanabe MA 《Journal of biological physics》2010,36(3):299-315
Roughly speaking, restitution is the dependence of recovery time of cardiac electrical activity on heart rate. Increased restitution
slope is theorized to be predictive of sudden death after heart injury such as from coronary artery occlusion (ischemia).
Adrenaline analogs are known to increase restitution slope in normal hearts, but their effects in failing hearts are unknown.
Twenty-six rabbits underwent coronary ligation (n = 15) or sham surgery (n = 11) and implantation of a lead in the heart for recording electrocardiograms. Eight weeks later, unanesthetized rabbits
were given 0.25–2.0 ml of 1 μmol/L isoprenaline intravenously, which increased heart rate. Heart rate was quantified by time
between QRS peaks (RR) and heart activity duration by R to T peak time (QTp). Ligated rabbits (n = 6) had lower ejection fraction than sham rabbits (n = 7, p < 0.0001) indicative of heart failure, but similar baseline RR (269 ± 15 vs 292 ± 23 ms, p = 0.07), QTp (104 ± 17 vs 91 ± 9 ms, p = 0.1), and isoprenaline-induced minimum RR (204 ± 11 vs 208 ± 6 ms, p = 0.4). The trajectory of QTp vs TQ plots displayed hysteresis and regions of negative slope. The slope of the positive slope
region was >1 in ligated rabbits (1.27 ± 0.66) and <1 in sham rabbits (0.35 ± 0.14, p = 0.004). The absolute value of the negative slope was greater in ligated rabbits (− 0.81 ± 0.52 vs − 0.35 ± 0.14, p = 0.04). Isoprenaline increased heart rate and slopes of restitution trajectory in failing hearts. The dynamics of restitution
trajectory may hold clues for sudden death in heart failure patients. 相似文献
13.
Yong-Yu Li Xue-Jin Li Shuai Lv Kun Li Yan-Na Li Zhi-Rong Gao Jia-Yan Feng Chang-Jie Chen Claus Schaefer 《Cell stress & chaperones》2010,15(5):583-591
Acute pancreatitis (AP) is an inflammatory process in which cytokines and chemokines are involved. After onset, extrapancreatic
stimuli can induce the expression of cytokines in pancreatic acinar cells, thereby amplifying this inflammatory loop. To further
determine the role and mechanism of irritating agents in the pathogenesis of AP, rat pancreatic tissues were stimulated with
ascitic fluid (APa) and serum (APs) from rats with AP or with lipopolysaccharide (LPS). In addition, the alteration of heat
shock protein 60 (HSP60) expression was evaluated. Rat pancreas was removed and meticulously snipped to fragments. The snips
were cultured for up to 48 h. During this period, the tissue viability as well as amylase and TNF-α levels in the supernatant
and the HSP60 expression in the pancreatic tissue before and after stimulation by APa, APs, and LPS were assayed time-dependently.
At different time-points during the culture, the viability and the amylase activity in the pancreatic tissue remained largely
stable. After stimulation with APa, APs, or LPS for 1 h, the pancreatic tissues showed some damage, and this was followed
by a sharp decrease in the viability accompanied by increased levels of amylase and TNF-α in the culture medium 2 or 4 h after
stimulation (p < 0.05). In contrast, both the HSP60 mRNA and protein levels had a relatively high expression in the freshly prepared tissue
fragments (0 h). As the culturing period was extended, the expression of HSP60 mRNA decreased only slightly; at the same time,
the HSP60 protein levels decreased over a prolonged culture time, significantly so from 12 through 48 h (p < 0.05). After stimulation with APs, APa, or LPS, both the expression of HSP60 mRNA and protein in the tissue fragments increased
slightly at 1 h and decreased significantly thereafter at 2 and 4 h (p < 0.05). APa, APs, or LPS induce injuries on isolated pancreatic tissues, accompanied by an altered HSP60 expression pattern
in a time-dependent manner. 相似文献
14.
L. N. Yatsenko L. G. Storchak N. T. Parkhomenko N. H. Himmelreich 《Neurophysiology》2008,40(4):243-251
We studied the effects of early postnatal hypoxia on the efficiency of active GABA transport through the plasma membrane of
synaptic terminals (synaptosomes) isolated from the cerebral cortex, hippocampus, and thalamus of rats and on non-stimulated
and Ca2+-stimulated GABA release. The state of hypoxia was induced by exposure of 10- to 12-day-old rats to a respiratory medium with
low O2 content (4% О2 and 96% N2) for 12 min (up to the initiation of clonico-tonic seizures). Animals were taken in the experiment 8 to 9 weeks after an
episode of hypoxic stress. The intensity of transmembrane transport of GABA was estimated according to accumulation of [3Н]GABA in a coarse synaptosomal fraction. The process was characterized by calculation of the Michaelis constant K
m
and also of the initial (within the 1st min) and maximum rates of accumulation of [3Н]GABA. The means of the initial rate of [3Н]GABA accumulation in preparations from the thalamus, cortex, and hippocampus were 205.5 ± 8.8, 266.2 ± 29.6, and 302.3 ± 31.2
pmol/min⋅mg protein, respectively. Hypoxic stress influenced the rates of accumulation of [3Н]GABA in synaptic terminals from the cortex and hippocampus but not in those from the thalamus. According to the characteristics
of the response to hypoxic stress, all experimental animals could be classified into two groups. In some rats, accumulation
of [3Н]GABA in both cortical and hippocampal synaptosomes decreased insignificantly (by about 15%), while in other animals this
parameter increased significantly (by nearly 50%) for the cortex and decreased by 21.5%, on average, for the hippocampus.
The affinity of the transporter with respect to [3Н]GABA in the cortex and hippocampus was nearly the same and showed no changes under the influence of hypoxia. The non-stimulated
release of [3Н]GABA after the influence of hypoxia increased in all structures, while the depolarization-induced Ca2+-dependent release of [3Н]GABA was intensified only in synaptosomes from the cerebral cortex. The mechanisms of development of modifications of GABA-ergic
processes under the influence of hypoxic stress in the course of the perinatal period are discussed.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 4, pp. 293–302, July–August, 2008. 相似文献
15.
Tatiana Kugelmeier Rodrigo del Rio do Valle Marcelo Alcindo de Barros Vaz Guimarães José Augusto Pereira Carneiro Muniz Frederico Ozanan Barros Monteiro Cláudio Alvarenga de Oliveira 《International journal of primatology》2011,32(3):605-615
A better understanding of a species’ reproductive physiology can help conservation programs to manage primates in the wild
and develop assisted reproductive technologies in captivity. We investigated whether measurements of fecal progestin and estrogen
metabolites obtained by a radioimmunoassay could be used to monitor the ovarian cycle of Alouatta caraya. We also compared the occurrence of vaginal bleeding with the hormone profiles. We collected fecal samples from 3 adult and
1 subadult captive female over 5 mo and performed vaginal cytology for the adults. The interval between fecal progestin surges
in the adult females was 19.11 ± 2.14 d (n = 18 cycles). Fecal progestin concentrations remained at basal values for 9.83 ± 2.21 d (n = 18) and rose to elevated values for 9.47 ± 0.72 d (n = 19). The subadult female showed basal levels of fecal estrogen and progestin concentrations throughout the study, suggesting
that our hormone measurements are valid to monitor the ovarian cycle. Bleeding periods coincided with basal levels of fecal
estrogens and progestin at intervals of 19.8 ± 0.9 d and lasted for 4.1 ± 1.0 d. Although we obtained these data from only
3 individuals, the results indicate that this species likely has a menstrual-type ovarian cycle. These data provide the first
endocrine profile for the Alouatta caraya ovarian cycle and are similar to results obtained for other howler species. This similarity is important for comparative
studies of howlers, allowing for a better understanding of their reproductive physiology and contributing to a critical information
base for managing Alouatta species. 相似文献
16.
Gigartina skottsbergii is a commercially important carrageenan producer that has been suffering severe extraction pressure in Chile’s Magellan Region
and Cape Horn Archipelago since 1998. In order to create baseline information for its cultivation and repopulation, we studied
the effects of agricultural fertilizers on growth of G. skottsbergii early developmental stages. The culture media utilized were: a) seawater + Bayfoland, b) seawater + Superphosphate, c) seawater
+ Urea, d) seawater + Provasoli and e) seawater as a control. The culture conditions were: a) 12L:12D photoperiod; b) temperature
8 ± 1°C and c) irradiance at 45 μmol photons m−2 s−1. After 60 days, higher relative growth rates between treatments were observed; the treatments that included Bayfoland and
Provasoli showed greater growth (382 ± 55 and 378 ± 50 μm, respectively,) compared to Superphosphate (88 ± 16 μm), control
(78 ± 10 μm) and Urea (70 ± 11 μm) treatments, after 81 days. The Urea treatment and the control had inhibitory effects on
G. skottsbergii germlings growth and survival, as evidenced by progressive loss of pigmentation and death after 60 days. These results showed
that Bayfoland was an excellent alternative to develop cultures. 相似文献
17.
Ethanol production by recombinant Escherichia coli strain FBR5 from dilute acid pretreated wheat straw (WS) by separate hydrolysis and fermentation (SHF) and simultaneous saccharification
and fermentation (SSF) was studied. The yield of total sugars from dilute acid (0.5% H2SO4) pretreated (160 °C, 10 min) and enzymatically saccharified (pH 5.0, 45 °C, 72 h) WS (86 g/l) was 50.0 ± 1.4 g/l. The hydrolyzate
contained 1,184 ± 19 mg furfural and 161 ± 1 mg hydroxymethyl furfural per liter. The recombinant E. coli FBR5 could not grow at all at pH controlled at 4.5 to 6.5 in the non-abated wheat straw hydrolyzate (WSH) at 35 °C. However,
it produced 21.9 ± 0.3 g ethanol from non-abated WSH (total sugars, 44.1 ± 0.4 g/l) in 90 h including the lag time of 24 h
at controlled pH 7.0 and 35 °C. The bioabatement of WS was performed by growing Coniochaeta ligniaria NRRL 30616 in the liquid portion of the pretreated WS aerobically at pH 6.5 and 30 °C for 15 h. The bacterium produced 21.6 ± 0.5 g
ethanol per liter in 40 h from the bioabated enzymatically saccharified WSH (total sugars, 44.1 ± 0.4 g) at pH 6.0. It produced
24.9 ± 0.3 g ethanol in 96 h and 26.7 ± 0.0 g ethanol in 72 h per liter from bioabated WSH by batch SSF and fed-batch SSF,
respectively. SSF offered a distinct advantage over SHF with respect to reducing total time required to produce ethanol from
the bioabated WS. Also, fed-batch SSF performed better than the batch SSF with respect to shortening the time requirement
and increase in ethanol yield. 相似文献
18.
Monica Daniela Doşa Laurentiu-Tony Hangan Eduard Crauciuc Cristina Galeş Mihai Nechifor 《Biological trace element research》2011,142(1):36-46
Research was performed on a group of 30 patients with non-insulin-dependent diabetes mellitus (NIDDM), who never received
antidiabetic medication before, and on a group of 17 healthy adults. The patients were administered treatment with metformin,
1,000 mg/day. Plasmatic and urinary concentration of magnesium have been measured, copper and zinc along with the concentrations
of glucose, HDL, LDL, cholesterol, tryglicerides, HbA1c, and total erythrocyte magnesium, in advance and after 3 months of
treatment. Data showed significant differences in the NIDDM group vs the control group: for plasma magnesium—1.95 ± 0.19 vs
2.20 ± 0.18 mg/dl, p < 0.001; urine magnesium—237.28 ± 34.51 vs 126.25 ± 38.22 mg/24 h, p < 0.001; erythrocyte magnesium—5.09 ± 0.63 vs 6.38 ± 0.75 mg/dl, p < 0.001; plasma zinc—67.56 ± 6.21 vs 98.41 ± 20.47 μg/dl, p < 0.001; urine zinc—1,347.54 ± 158.24 vs 851.65 ± 209.75 μg/24 h, p < 0.001; plasma copper—111.91 ± 20.98 vs 96.33 ± 8.56 μg/dl, p < 0.001; and urine copper—51.70 ± 23.79 vs 36.00 ± 11.70 μg/24 h, p < 0.05. Treatment with metformin for 3 months modified significant erythrocyte magnesium—5.75 ± 0.61 vs 5.09 ± 0.63 mg/dl,
p < 0.001 and urine magnesium—198.27 ± 27.07 vs 237.28 ± 34.51 mg/24 h, p < 0.001, whereas it did not modify significant the plasmatic and urinary concentration of the other cations. The erythrocyte
magnesium concentration was inversely correlated with HbA1c (r = −0.438, p = 0.015). The plasma level of copper was positively correlated with HbA1c (r = 0.517, p < 0.003), tryglicerides (r = 0.534, p < 0.003), and cholesterol (r = 0.440, p < 0.05), and the plasma level of zinc was inversely correlated with glycemia (r = −0.399, p = 0.029). Our data show a significant action of metformin therapy, by increasing the total intraerythrocyte magnesium concentration
and decreasing the urinary magnesium elimination, positively correlated with the decrease of glycemia and HbA1c in NIDDM patients. 相似文献
19.
Data on the concentration of the elements in the human body are important, for example, to estimate the amounts required to
maintain a good healthy state or find their connections with morbidity and mortality. In this paper, the concentration of
copper (by flame atomic absorption spectrometry) in material obtained from autopsy cases of nonpoisoned people (n = 130), aged from 14 to 80 years, between 1990–2006, is presented. The following values were found (mean ± SD in micrograms
of copper per gram or per milliliter): brain 3.32 ± 1.50 (n = 43), liver 3.47 ± 1.51 (n = 79), kidney 2.15 ± 0.90 (n = 76), stomach 1.10 ± 0.76 (n = 65), intestines 1.54 ± 1.19 (n = 25), lung 1.91 ± 1.30 (n = 27), spleen 1.23 ± 0.28 (n = 3), heart 3.26 ± 0.59 (n = 5), bile 3.60 ± 1.67 (n = 13), and blood 0.85 ± 0.19 (n = 73). 相似文献
20.
Henry Bernard Ikki Matsuda Goro Hanya Abdul Hamid Ahmad 《International journal of primatology》2011,32(1):259-267
Primates spend about half of their lives at sleeping sites, and their choice of sleeping sites may affect individual survival.
We identified a total of 88 trees used by proboscis monkeys (Nasalis larvatus) as night sleeping sites on 16 nights from June to September 2008 in riverine, mangrove, and mixed mangrove–riverine forests
along the Garama River, a tributary of the Klias River, in the west of Sabah, Malaysia. We recorded 11 variables for each
tree, including the species, physical structure, distance from the riverbank, and connectivity with surrounding trees. We
compared sleeping trees with 114 trees with ≥30 cm girth at breast height (GBH) located ≤50 m of the riverbank in 8 botanical
plots (total 1 ha). Trees in the plots represented the general vegetation patterns of the study area. Choice of sleeping trees
did not depend on the tree species. Although sleeping trees included trees ≤46 m from the river, those closer to riverbanks
(5–35 m, n = 76) were more likely to be used as sleeping sites. Compared to the available trees, sleeping trees had larger trunks (mean±SD = 143.6 ± 56.9 cm
GBH), and were taller (mean±SD = 34.3 ± 8.1 m), with greater number (median = 6; range = 12) and larger (mean±SD = 24.1 ± 15.2 cm
circumference) main branches. They were also located near to other trees, with overlapping branches, creating good arboreal
connectivity. Choice of sleeping trees by proboscis monkeys is likely to be related to risks of predation and injury from
falling, as well as ease of social interaction and efficiency of locomotion. 相似文献