Heat stress affects dairy cow health status through blood oxygen availability

Background Rises in global warming and extreme weather occurrence make the risk of heat stress(HS)induced by high ambient temperatures more likely in high-yielding dairy cows,resulting in low milk quality and yield.In ani-mals,oxygen is involved in many physiological and metabolic processes,but the effects of HS on oxygen metabolism remain unclear.Thus,the current study aimed to investigate how oxygen metabolism plays a role in health status of dairy cows by measuring the milk yield,milk composition,and blood biochemical variables of cows under different levels of HS:none(No-HS),mild(Mild-HS),and moderate HS(Mod-HS).Results The HS significantly increased rectal temperature(Ptreat<0.01)and respiration rate(Ptreat<0.01).Under Mod-HS,greater Na+(P<0.05)and lower total CO_(2),and pH(P<0.05)were observed relative to those under No-HS and Mild-HS.Oxygen concentrations in both coccygeal artery and mammary vein(Ptreat<0.01)were lower under Mod-HS than under No-HS.Coccygeal vein concentrations of heat shock protein 90(HSP90)(P<0.05)increased during Mod-HS compared with those in cows under No-HS.Malondialdehyde increased during Mod-HS,and glu-tathione peroxidase(P<0.01)increased during Mild-HS.Coccygeal vein concentrations of vascular endothelial growth factor(P<0.01),heme oxygenase-1(P<0.01),and hypoxia-inducible factor 1α(P<0.01)were greater in cows under Mod-HS than those under No-HS.Red blood cell count(P<0.01)and hemoglobin concentration(P<0.01)were lower in the coccygeal vein of dairy cows under Mild-and Mod-HS than those of cows under No-HS.Conclusions Exposure to HS negatively impacts the health status and lactation performance of dairy cows by limit-ing oxygen metabolism and transportation.However,the specific mechanism by which HS affects mammary function in cows remains unclear and requires further exploration.

Supplementation of vitamin E or a botanical extract as antioxidants to improve growth performance and health of growing pigs housed under thermoneutral or heat-stressed conditions

Background Heat stress has severe negative consequences on performance and health of pigs,leading to significant economic losses.The objective of this study was to investigate the effects of supplemental vitamin E and a botanical extract in feed or drinking water on growth performance,intestinal health,and oxidative and immune status in grow-ing pigs housed under heat stress conditions.Methods Duplicate experiments were conducted,each using 64 crossbred pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,respectively.Pigs(n=128)were housed individually and assigned within weight blocks and sex to a 2×4 factorial arrangement consisting of 2 environments(thermo-neutral(21.2℃)or heat-stressed(30.9℃))and 4 supplementation treatments(control diet;control+100 IU/L of D-α-tocopherol in water;control+200 IU/kg of DL-α-tocopheryl-acetate in feed;or control+400 mg/kg of a botanical extract in feed).Results Heat stress for 28 d reduced(P≤0.001)final body weight,average daily gain,and average daily feed intake(-7.4 kg,-26.7%,and-25.4%,respectively)but no effects of supplementation were detected(P>0.05).Serum vitamin E increased(P<0.001)with vitamin E supplementation in water and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for the botanical extract(1.64 vs.1.67 mg/kg)and was greater when supplemented in water vs.feed(P=0.002).Liver vitamin E increased(P<0.001)with vitamin E supplementations in water(3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extract(3.9 vs.4.9 mg/kg).Serum malondialdehyde was reduced with heat stress on d 2,but increased on d 28(interaction,P<0.001),and was greater(P<0.05)for antioxidant supplementation compared to control.Cellular proliferation was reduced(P=0.037)in the jejunum under heat stress,but increased in the ileum when vitamin E was supplemented in feed and water under heat stress(interaction,P=0.04).Tumor necrosis factor-αin jejunum and ileum mucosa decreased by heat stress(P<0.05)and was reduced by vitamin E sup-plementations under heat stress(interaction,P<0.001).Conclusions The addition of the antioxidants in feed or in drinking water did not alleviate the negative impact of heat stress on feed intake and growth rate of growing pigs.

Effect of organic mineral supplementation in reducing oxidative stress in Holstein calves during short‑term heat stress and recovery conditions

Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)during short-term heat stress(HS)and recovery periods.Eight Holstein calves were randomly assigned to four treatment groups:no mineral supplementation(Con),inorganic minerals(IM),organic minerals(OM),and high-concentration organic minerals(HOM)and two thermal environments(HS and recovery)using 4×2 factorial arrangement in a crossover design of four periods of 35 d.Calves were maintained in a temperature-controlled barn.The experimental period consisted of 14 d of HS,14 d of recovery condititon,and a 7-d washing period.Results Body temperature and respiration rate were higher in HS than in the recovery conditions(P<0.05).Selenium concentration in serum was high in the HOM-supplemented calves in both HS(90.38μg/dL)and recovery periods(102.00μg/dL)(P<0.05).During the HS period,the serum cortisol was 20.26 ng/mL in the HOM group,which was 5.60 ng/mL lower than in the control group(P<0.05).The total antioxidant status was the highest in the OM group(2.71 mmol Trolox equivalent/L),followed by the HOM group during HS,whereas it was highest in the HOM group(2.58 mmol Trolox equivalent/L)during the recovery period(P<0.05).Plasma malondialdehyde and HSP70 levels were decreased by HOM supplementation during the HS and recovery periods,whereas SOD and GPX levels were not significantly affected(P>0.05).The principal coordinate analysis represented that the overall rumen microbiota was not influenced by mineral supplementation;however,temperature-induced microbial structure shifts were indicated(PERMANOVA:P<0.05).At the phylum level,Firmicutes and Actinobacteria decreased,whereas Fibrobacteres,Spirochaetes,and Tenericutes increased(P<0.05),under HS conditions.The genus Treponema increased under HS conditions,while Christensenella was higher in recovery conditions(P<0.05).Conclusion HOM supplementation during HS reduced cortisol concentrations and increased total antioxidant status in Holstein bull calves,suggesting that high organic mineral supplementation may alleviate the adverse effects of HS.

Changes of Water Status and Different Responses of Osmoregulants in Jatropha Curcas L. Seedlings to Air-drought Stress

[Objective] The study aimed to investigate the changes of water status and different responses of osmoregulants during air-drought stress,to better understand mechanisms of drought resistance in Jatropha Curcas L. [Methods] The 12-day-old J. curcas seedlings were held in a climate chamber at 25/20 ℃（day/night）,16 hours illumination,and 75% of relative humidity for air-drought treatment,and the changes of water potential,osmotic potential and the content of soluble sugar,proline,betaine were measured. [Results] Water potential and osmotic potential in leaves of J. curcas seedlings dropped significantly,pressure potential lost during air-drought stress,and the contents of osmoregulants soluble sugar,proline and betaine rose significantly to different extent in the leaves and stems. [Conclusion] Osmoregulants in the leaves and stems respond differently to air-drought stress,and in general leaves are much more responsive to the drought than stems of J. curcas seedlings.

Effect of Soil Drought Stress on Leaf Water Status, Membrane Permeability and Enzymatic Antioxidant System of Maize

A simulation experiment on the responses of maize (Zea mays L.) from the third leaf stage to maturity for different soil water levels (well-watered, moderately stressed, and severely stressed) was conducted by controlling irrigation and using a mobile rain shelter in a neutral loam, meadow soil to determine the effects on leaf water status, membrane permeability and enzymatic antioxidant system for different growth stages. The results indicated that drought stress relied on drought intensity and duration, with more severe drought stress creating more serious effects on maize. Compared with well-watered conditions, during the silking and blister stages moderate stress did not significantly change the relative water content (RWC) and did change significantly the relative conductivity (RC) (P < 0.05) of the leaves; however, severe stress did significantly decrease (P < 0.01) the leaf RWC and increase (P < 0.01) membrane permeability (leaf relative conductivity). Furthermore, under severe drought stress antioxidant enzyme activities declined significantly (P < 0.01) in later stages, namely for superoxide dismutase (SOD) the tasseling and blister stages, for peroxidase (POD) the milk stage, and for catalase (CAT) during the tasseling, blister, and milk stages. Meanwhile, membrane lipid peroxidation (measured as malondialdehyde content) significantly increased (P < 0.01) in all stages.

Growth performance,oxidative stress and immune status of newly weaned pigs fed peroxidized lipids with or without supplemental vitamin E or polyphenols

Background:This study evaluated the use of dietary vitamin E and polyphenols on growth,immune and oxidative status of weaned pigs fed peroxidized lipids.A total of 192 piglets(21 days of age and body weight of 6.62±1.04 kg)were assigned within sex and weight blocks to a 2×3 factorial arrangement using 48 pens with 4 pigs per pen.Dietary treatments consisted of lipid peroxidation(6%edible soybean oil or 6%peroxidized soybean oil),and antioxidant supplementation(control diet containing 33 IU/kg DL-α-tocopheryl-acetate;control with 200 IU/kg additional dl-α-tocopheryl-acetate;or control with 400 mg/kg polyphenols).Pigs were fed in 2 phases for 14 and 21 days,respectively.Results:Peroxidation of oil for 12 days at 80°C with exposure to 50 L/min of air substantially increased peroxide values,anisidine value,hexanal,and 2,4-decadienal concentrations.Feeding peroxidized lipids decreased(P<0.001)body weight(23.16 vs.18.74 kg),daily gain(473 vs.346 g/d),daily feed intake(658 vs.535 g/d)and gain:feed ratio(719 vs.647 g/kg).Lipid peroxidation decreased serum vitamin E(P<0.001)and this decrease was larger on day 35(1.82 vs.0.81 mg/kg)than day 14(1.95 vs.1.38 mg/kg).Supplemental vitamin E,but not polyphenols,increased(P≤0.002)serum vitamin E by 84%and 22%for control and peroxidized diets,respectively(interaction,P=0.001).Serum malondialdehyde decreased(P<0.001)with peroxidation on day 14,but not day 35 and protein carbonyl increased(P<0.001)with peroxidation on day 35,but not day 14.Serum 8-hydroxydeoxyguanosine was not affected(P>0.05).Total antioxidant capacity decreased with peroxidation(P<0.001)and increased with vitamin E(P=0.065)and polyphenols(P=0.046)for the control oil diet only.Serum cytokine concentrations increased with feeding peroxidized lipids on day 35,but were not affected by antioxidant supplementation(P>0.05).Conclusion:Feeding peroxidized lipids negatively impacted growth performance and antioxidant capacity of nursery pigs.Supplementation of vitamin E and polyphenols improved total antioxidant capacity,especially in pigs fed control diets,but did not restore growth performance.

Baseline Iron Status and Indices of Oxidative Stress in a Cohort of Pregnant Women in Kinshasa, DR Congo

Objective: To determine baseline iron and oxidative status in a cohort of pregnant women before iron supplementation in our setting. Background: Screening of iron deficiency before supplementation during pregnancy has been scarce. Therefore, following routine iron supplementation confounding results might be found in outcomes of groups of patients considered. Taking in account that body/serum iron status is reportedly linked to maternal oxidative status, we aimed to associate assessment of baseline iron and oxidative status of women in need of oral supplementation during pregnancy. Methods: This is a cross-sectional study concerning 74 women attending antenatal care at the University Clinics of Kinshasa from September 2017 throughout June 2018, with a singleton pregnancy not exceeding 19 weeks, regardless of age and parity. Variables of the study included sociodemographic and anthropometric ones along with parameters of iron status (hemoglobin, hematocrit, ferritin, serum iron, transferrin and iron saturation capacity). Oxidative status was assessed using superoxide dismutase (SOD) and uric acid as antioxidants, while oxidant agents were oxidized LDL and blood glucose (beside serum iron and ferritin). According to local standards anemia was defined as hemoglobin 10 g/L and pathologic serum ferritin as 15 ng/ml. For statistical calculations we used t-test, chi-square test and Pearson’s correlation test, the significance being stated at p ≤ 0.05. Results: At recruitment (15.9 ± 1.7 9 week gestational age) mean hemoglobin value of the overall study group was 10.3 ± 1.5 g/dl. Anemia was diagnosed to 39 women that represented 52.2% of the study group, most of anemic women belonging to low socioeconomic sub-group (69.2% vs 29%;P < 0.001). The majority was para 2, with average weight of 70.2 ± 14.5 Kg (P not significant between sub-groups) and BMI of 26 ± 5.2 Kg/m2 (P < 0.01). The proportion of obeses was 18.9%. The proportion of intestinal parasitosis was significantly higher among anemic women (61.5% vs 34.3%;P < 0.02) that had lower alimentary iron intake (22.8 ± 4.9 gr/day vs 31.4 ± 9.5 gr;P < 0.001). Of markers of iron status serum ferritin and iron were lower in anemic women (7.5 ± 3.9 ng/ml vs 35.7 ± 17.1 ng/ml;P < 0.001 and 52.7 ± 38.9 μg/dl vs 96.2 ± 41.8 μg/dl, respectively. Both sub-groups were similar in serum transferrin. As of markers of oxidative stress anemic women had significantly higher superoxide dismutases (SOD) (1056.4 ± 762.1 UI/L vs 682.6 ± 543.9 UI/L (P < 0.02) and oxidizedd anti LDL Ac (439.6 ± 209.5 UI/L vs 192.8 ± 136.3 UI/L (P < 0.001). Serum iron, ferritin, SOD and oxidized LDL were more likely to assess iron and oxidative status in our setting. Conclusion: The rate of anemic mothers found in our study (52.2%) has been quite constant in our setting for years, meaning endemicity. Serum iron and ferritin were significantly lower in anemic women, which is supportive of routine iron supplementation during pregnancy. Significantly higher level of SOD and oxidized LDL in anemic women suggests that maternal anemia may count into oxidative stress likely to be found in these women.

Pig Social Status and Chronic Cold or Crowd Stressors Differentially Impacted Immune Response

The objectives of this study were to determine the effects of 4-day of cold and crowding stressors and social status on pig immune responsiveness to these stressors. Three unfamiliar white crossbred female pigs were mixed and assigned to ambient temperatures of either 8°C (COLD) or 22°C (control;TN) and floor-space of either 0.26 m2/pig (reduced, CROWD) or 0.45 m2/pig (adequate, CONT) over six blocks (n = 72). Pigs were identified as dominant (DOM), intermediate (INT), or submissive (SUB) based on aggressive encounters that occurred during the first 24-h post-mixing. There were no interactive effects of temperature × floor-space on immune indices. There was social status × stressor for body weight, natural killer (NK) cell cytotoxicity and phagocytosis (P < 0.05). DOM pigs that were COLD or CROWD gained the least amount of body weight compared to either INT or SUB pigs (P < 0.01). INT and SUB pigs subjected to CROWD stress gained more weight compared to their counterparts subjected to COLD temperature or CONT floor-space (P < 0.05). NK cytotoxicity was greater among CROWD-INT pigs and phagocytosis was greater among COLD- and CROWD-SUB pigs. Also, INT pigs had lower T and B cell proliferation regardless of the stressor. COLD stress significantly reduced NK cytotoxicity, total Immunoglobulin-G, and B-cell proliferation and enhanced total WBC counts and T-cell proliferation. These data imply that various immune indices were either enhanced or suppressed by COLD stress, but concurrent exposure to CROWD stressor did not exacerbate these effects. Moreover, social status played a role in determining a pig’s immune responsiveness as it modulated differential homeostatic stress response as the pig attempted to cope with stress.

Unbalanced biotransformation metabolism and oxidative stress status: implications for deficient fatty acid oxidation

The concept of accumulating xenobiotics within the human body as a health risk is well known. However, these compounds can also be endo-genous, as in the case of inborn errors of me-tabolism, and lead to some of the same symp-toms as seen in xenobiotic intoxication. Bio-transformation of both exogenous and endo-genous toxic compounds is an important function of the liver, and the critical balance between these systems is of fundamental importance for cellular health. We propose a novel model, to describe the critical balance between Phase I and Phase II biotransformation and how a disturbance in this balance will increase the oxidative stress status, with resulting pathological consequences. We further used deficient fatty acid oxidation to verify the proposed model, as deficient fatty acid oxidation is associated with the accumulation of characteristic metabolites. These accumulating metabolites undergo both Phase I and Phase II biotransformation reactions, with resulting depletion of biotransformation substrates and co-factors. Depletion of these important biomolecules is capable of disturbing the balance between Phase I and Phase II reactions, and disturbance of this balance will increase oxidative stress status. The value of the proposed model is illustrated by its application to a clinical case investigated in our laboratory. In this case the possibility of deficient fatty acid oxidation only became evident once the critical balance between Phase I and Phase II biotransformation was restored with oral replenishment of biotransformation substrates. In addition to bio-chemical improvement, there was also significant clinical improvement. The significance of this model lies within the treatment possibilities, as the assessment of biotransformation metabolism and oxidative stress status can lead to the development of nutritional treatment strategies to correct imbalances. This in turn may reduce the chances of, or delay the onset of certain disease states.

Increased oxidative stress and altered antioxidants status in patients with chronic allergic rhinitis

Background: Allergic rhinitis is an inflammatory disorder of the upper airways. Although several oxidants and antioxidants are likely to be involved, alterations in only limited parameters have been studied. Objective: In this study an attempt has been made to study the oxidant-antioxidant imbalance by investigating changes in a wide range of oxidants and antioxidants in the blood. Methods: Blood samples were obtained from 39 chronic allergic rhinitis patients (males 24, females 15), aged 20-70 (mean age 36.33 ± 2.03) years and 53 individuals (36 males, 17 females);aged 24 to 64 (mean age 45.42 ± 1.36) years. Duration of allergic rhinitis was 1.77 ± 0.237 years. In the study group, nasal symptoms were scored and the results were recorded. The patients were classified as having perennial Allergic rhinitis (PAR) if they had had at least 2 rhinitis symptoms (sneezing, rhinorrhea, nasal obstruction, itching) for at least 6 months a year in the previous 2 years and if they had a positive skin prick test response to at least 1 clinically significant perennial allergen (e.g., house dust mites, molds, cockroach, cockroach excrement grass and tree pollen, cat and dog epithelia and molds, or animal dander). They had no other allergic diseases except persistent allergic rhinitis diagnosed by the physical and history examination. Erythrocyte lipid peroxidation, erythrocyte antioxidants viz., glutathione, glutathione reductase, superoxide dismutase, catalase and plasma antioxidants viz., ceruloplasmin, glutathione-S-transferase, vitamin C, total antioxidant activity were estimated in the above two groups. Results: Erythrocyte lipid peroxidation (0 hour, p < 0.01) and superoxide dismutase (p < 0.01) were significantly higher, whereas plasma vitamin C (p < 0.001), ceruloplasmin (p < 0.05) and total antioxidant activity (p < 0.001) were significantly lower in chronic allergic rhinitis patients when compared to controls. Plasma Glutathione S transferase and erythrocyte catalase, glutathione, and glutathione reductase remained unchanged from normal subjects. Conclusion: The changes in different parameters indicate an imbalance in the oxidant and antioxidant status in chronic allergic rhinitis patients. Further studies are required to investigate the potential for antioxidant supplements to be used as routine therapy in chronic allergic rhinitis patients. Capsule summery: The study shows that the body is trying to cope for the oxidative stress by altering the enzyme levels. But external supplement may also be required as the total antioxidant levels are very much depleted.

Cinnamon Attenuates Cognitive Dysfunction,Hippocampal Oxidative Stress and Neurodegeneration Following Status Epilepticus in Young Male Rats

The present study explores the neuroprotective effects of the natural food product Cinnamomum cassia or Cinnamon(CIN)on lithium pilocarpine(Li-Pc)induced SE in experimental rats to look into a possibility of it being used as antiepileptic drug.Recent studies have shown significant potential of pharmacological,prophylactic or therapeutic use of CIN in many beneficial activities in the body.The animals received CIN pre-treatment before induction of SE.Besides the severity of the seizures,other parameters like cognitive behavioral dysfunction,hippocampal oxidative stress and histological abnormalities in the hippocampus of animals induced with SE by lithium(Li)in 3 mEq/ml/kg dose,i.p.followed 20 h later by pilocarpine(Pc)in 20 mg/ml/kg dose,s.c.CIN was administered intraperitoneally at the doses of 25 and 50 mg/mL/kg,30 minutes before Pc injection.Mortality(if any)within 24 hours was also recorded.Ethical approval was obtained from the Ethics Committee Review Board of the College of Pharmacy of King Saud University,Riyadh,Saudi Arabia.Treatment with CIN significantly ameliorated the frequency and severity of epileptic seizures in a dose-dependent manner.The cognitive dysfunctions were improved,hippocampal oxidative stress was ameliorated and neuronal cell loss in the hippocampus were also attenuated significantly and dose-dependently by CIN.Possible therapeutic application of CIN as an antiepileptic and as an antioxidant for the treatment of SE has a great potential and warrants further studies.

Insulin resistance in H pylori infection and its association with oxidative stress

AIM: To determine the insulin resistance (IR) and oxidative status in H pylori infection and to find out if there is any relationship between these parameters and insulin resistance. METHODS: Fifty-five H pylori positive and 48 H pylori negative patients were enrolled. The homeostasis model assessment (HOMA) was used to assess insulin resistance. Serum total antioxidant capacity (TAC), total oxidant status (TOS) and oxidative stress index (OSI) were determined in all subjects. RESULTS: The total antioxidant capacity was significantly lower in H pylori positive group than in H pylori negative group (1.36 ± 0.33 and 1.70 ± 0.50, respectively; P < 0.001), while the total oxidant status and oxidative stress index were significantly higher in H pylori positive group than in H pylori negative group (6.79 ± 3.40 and 5.08 ± 0.95, and 5.42 ± 3.40 and 3.10 ± 0.92, respectively; P < 0.001). Insulin resistance was significantly higher in H pylori positive group than in H pylori negative group (6.92 ± 3.86 and 3.61 ± 1.67, res- pectively; P < 0.001). Insulin resistance was found to be significantly correlated with total antioxidant capacity (r = -0.251, P < 0.05), total oxidant status (r = 0.365, P < 0.05), and oxidative stress index (r = 0.267, P < 0.05). CONCLUSION: Insulin resistance seems to be associated with increased oxidative stress in H pylori infection. Further studies are needed to clarify the mechanisms underlying this association and elucidate the effectof adding antioxidant vitamins to H pylori eradication therapy on insulin resistance during H pylori infection.

Response of spikelet water status to high temperature and its relationship with heat tolerance in rice

In rice, high-temperature stress(HT) during flowering results in decreased grain yield via a reduction in spikelet fertility;however, the effect of plant water status on spikelet fertility under HT remains unknown. To investigate the relationship between spikelet water status and spikelet fertility under HT, two experiments were performed under temperature-controlled conditions using four genotypes with varying tolerance to HT. Rice plants were exposed to HT for seven consecutive days during the flowering stage under three soil water treatments(soil water potential 0, -20, and -40 kPa), as well as under hydroponic conditions in a separate experiment. HT significantly decreased spikelet fertility, pollen fertility, and anther dehiscence under each of the three water treatments. HT significantly increased the spikelet transpiration rate, and this change was accompanied by a significant decrease in the internal temperature of the spikelets. HT decreased pollen grain diameter in heat-sensitive genotypes. HT had varying effects on the water potential of panicles and anthers but increased anther soluble-sugar concentration. Different aquaporin genes showed different expression profiles under HT, and the expression levels of PIPs for plasma membrane intrinsic proteins and TIPs for tonoplast intrinsic proteins increased in anthers but decreased in glumes.Correlation analyses showed that anther dehiscence and pollen(spikelet) fertility were tightly associated with anther water status, and the expression levels of almost all anther aquaporin genes were significantly correlated with anther dehiscence under HT. In summary, an increased spikelet transpiration rate and decreased internal spikelet temperature were associated with alleviation of the effects of HT in rice genotypes with varying degrees of heat tolerance, and the response of spikelet water status to HT, involving increased total expression of aquaporins and soluble sugar content, thereby improved pollen fertility,anther dehiscence, and spikelet fertility, especially in heat-resistant genotypes. The heat-resistant genotypes N22 and SY63 may adopt different approaches to reduce heat damage.

Towards a more flexible representation of water stress effects in the nonlinear Jarvis model

To better interpret summer maize stomatal conductance （gs） variation under conditions of changing water status at different growth stages, three water stress indicators, soil water content （SWC）, leaf-air temperature difference （AT） and leaf level water stress index （CWSIL） were employed in Jarvis model, which were Js, JT and Jc models respectively. Measurements of gs were conducted in a summer maize field experiment during the year 2012-2013. In the insufficient irrigation exper- iment, three levels of irrigation amount were applied at four different growth stages of summer maize. We constructed three scenarios to evaluate the performance of the three water stress indicators for estimating maize gs in a modified Jarvis model. Results showed that JT and Jc models had better simulation accuracy than the Js model, especially at the late growth stage （Scenario 1） or considering the plant recovery compensation effects （Scenario 2）. Scenario 3 indicated that the more environmental factors were adopted, the better prediction performance would be for Js model. While for JT model, two environmental factors （photosynthesis active radiation （PAR）, and vapor pressure deficit （VPD）） seemed good enough to obtain a reliable simulation. When there were insufficient environmental data, CWSI, would be the best option. This study can be useful to understand the response of plant stomatal to changing water conditions and will further facilitate the application of the Jarvis model in various environments.

The Effectiveness of Physical Exercise on Psychological Status, and Sleep Quality among Jordanian Patients Undergoing Hemodialysis: Literature Review

Background: Patients receiving hemodialysis are suffered from several psychological complications, and they required to receive safe, feasible, and applicable interventions to improve their psychological health. Practicing physical exercises were used in the literature as a possible intervention to improve patient’s outcomes. Purpose: The current literature review aimed to evaluate the effectiveness of physical exercises on psychological status, and sleep quality among patients undergoing hemodialysis, and to detect the gab in the Jordanian literature about the effectiveness of practicing physical exercises on psychological status, and sleep quality among patients undergoing hemodialysis. Methods: The design of the current article was literature review of fifty studies. Results: The current review revealed that most of the research studies were conducted to describe the levels and prevalence’s of psychological and mental complication of hemodialysis process, and to evaluate the impact of different types and methods of physical exercises on physical, psychological, and functional outcomes among patients undergoing hemodialysis. However, there are no agreement about the type, time, and intensity of physical exercises, and its impact on patients’ psychological outcomes. In Jordanian context, there are no experimental studies were conducted about the effectiveness of physical exercises on psychological status and sleep quality among patients undergoing hemodialysis. Conclusion: It is imperative for researchers to fill the gap that existed in the body of knowledge regarding the effectiveness of physical exercises on psychological outcomes among patients undergoing hemodialysis in order to improve psychological well-being and improve both quality of life for patients, and quality of nursing care.

Increased Oxidant Stress and Inflammation in Patients with Chronic Schizophrenia

Background: Several lines of evidence, including postmortem studies, suggest increased oxidative stress and inflammation in patients with schizophrenia. Alteration of oxidative stress markers has been reported in schizoprenia studies, but with inconsistent results. Oxidized low-density lipoproteins (oxLDL) have been reported to be capable of eliciting neurocytotoxicity. On the other hand, paraoxonase (PON1), an arylesterase(ARE), plays a role in protection against oxidative modifications of LDL and is considered to be one of the antioxidant enzymes. There are no studies showing the changes in oxidative stress and inflammation together, nor the activities of PON1 and ARE in schizophrenic patients. In this study, we examined PON1, ARE activities and oxidative/anti-oxidative markers in patients with chronic schizophrenia and healthy controls. Methods: We recruited 30 male chronic schizophrenic patients and 30 male healthy control subjects and examined C-reactive protein(CRP), fibrinogen, PON1, ARE and plasma total antioxidant status (TAS) and total oxidant status (TOS), oxidative stress index(OSI) in both groups. Schizophrenia symptoms were assessed using the positive and negative syndrome scale (PANSS). The related routine lipid profile parameters including HDL were also examined. Results: Patients had significantly higher CRP, fibrinogen, TOS and OSI levels;but the patients and control subjects did not differ on activities of the antioxidant enzymes PON1 and ARE. Interestingly, there were not any group differences in the lipid profile parameters except the triglyceride levels, that increased significantly in the patient group. Conclusions: In the present study, reporting the ARE activities besides the PON1 activities in schizophrenic patients for the first time, we showed that PON1 and ARE enzyme activities were not statistically different in patients with chronic schizophrenia. This study provides additional evidence of increased oxidative stress and inflammation in chronic schizophrenia, but no alterations in the antioxidant status were observed. Our results suggest that other mechanisms than the high density lipoprotein(HDL)-disfunctionality, namely decreases in PON1 or ARE enzyme activities, are more important in oxidative or antioxidative pathophysiological processes in schizophrenia.

Water Stress Estimation from NDVI-Ts Plot and the Wet Environment Evapotranspiration

In this work we present a new simple index to estimate water stress (WS) for different types of surfaces, from remotely sensed data. We derive a WS index, named WSIEw, modifying the Water Deficit Index (WDI) proposed by Moran et al. by using the wet environment evapotranspiration (Ew) instead of the potential evapotranspiration (Epot) concept. Jiang and Islam model was used to simulate actual evapotranspiration (ET) and Priestley and Taylor equation to estimate Ew. The WSIEw results were compared to ground observations of ET, precipitation (PP), soil temperature (Tsoil) and soil moisture (SM) in the Southern Great Plains-EEUU. Preliminary results suggest the method is sensitive to the water status of different surfaces. However, the WSIEw would range from 0 to 0.7, having a value of 0.4 for a dry surface with 5% of SM. The methodology is operationally simple and easy to implement since it requires only information from remote sensors.

Red onion extract(Allium cepa L.)supplementation improves redox balance in oxidatively stressed rats

Onions,consumed worldwide,are a good source of dietary phytochemicals with proven antioxidant properties.Catechin and quercetin are the most common and widely consumed flavonoids.The present study aimed to investigate the possible protective effect of onion extract as well as flavonoids(catechin and quercetin)on rats subjected to oxidative stress by mercuric chloride(HgCl2)treatment.Experiments were conducted on rat erythrocytes,which are a good model system to study oxidative stress.Results show that the oxidative stress induced by HgCl2 in Wistar rats resulted in substantially increased erythrocyte lipid peroxidation and higher activity of red cell plasma membrane redox system(PMRS)along with corresponding decrease in the intracellular reduced glutathione and antioxidant activity.Onion extract supplementation significantly(P<0.05)attenuated these adverse effects of HgCl2.Flavonoid supplementation resulted in a slightly higher antioxidant response compared to onion extract.We conclude that supplementation of these flavonoids results in normalization of erythrocyte PMRS activity which provides onion(rich in quercetin),a novel mechanism to exert its antioxidant effect against HgCl2-induced oxidative stress in rat erythrocytes in vivo.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

Family Status and Dilemma of HIV Positive Subjects

Objective To understand the family status and dilemma of HIV positive subjects and provide some related suggestions. Methods Constructured questionnaire and in-depth interview were used to survey their psychological needs of the 111 HIV positive subjects and AIDS patients from 4 provinces in China. Results HIV positive subjects and AIDS patients had strong mental stress. All of them hope to get support from their families; the most difficulty the subjects faced was economic poor. Conclusion It is a highlight to promote AIDS education to establish a good social environment in which HIV positive subjects and AIDS patients can live quietly and happily. And psychological support from their families and the society is very important to HIV positive subjects and AIDS patients.

Effect of Hormonal Contraceptives on the Total Antioxidants Status of Women from Isolo, Lagos State, Nigeria

The use of hormonal contraceptives has been implicated in the depletion of serum antioxidants and resultant promotion of oxidative stress which is associated with various disorders including cardiovascular disease and cancer. This study investigated serum total antioxidant status (TAS) in women taking hormonal contraceptives and compared their results with non-contraceptive users (age- and sex-matched). Sixty women aged 30 - 45 years, were enrolled for the study which included forty-five users of hormonal contraceptives from the Planned Parenthood Federation of Nigeria, Isolo, Lagos state and fifteen age-matched, apparently healthy, non-contraceptive users from the same geographical location were selected as controls. The in vitro determination of the serum total antioxidant status (TAS) was performed using Biorex enzymatic kit. Data obtained were statistically analyzed using student’s t-test and P < 0.05 was considered significant. The serum levels of TAS in the users of hormonal contraceptives were significantly lower than non-users (P < 0.05). The study concluded that women on hormonal contraceptives especially those taking either combined oral or combined injectable contraceptives were at risk of developing disorders associated with reduced levels of serum antioxidants.