Copper and Zinc Status in Psoriasis: Correlation with Severity

Psoriasis is a common and an inflammatory skin disease. Trace elements play an important role in the skin metabolism such as keratinisation and melanin formation as well as immunological and inflammatory reactions. Henceforth, the present study was aimed to evaluate the essential metals with special reference to Cu and Zn. In this study, 72 psoriatic patients and 50 controls were enrolled. On the basis of PASI score psoriatic group comprising of 48 mild and 24 severe psoriatic patients were grouped. The serum trace elements analysis in the subjects revealed that serum Cu levels and Cu/Zn ratio was significantly higher in the psoriatic patients as compared to controls. Interestingly, severity of the psoriasis was well correlated with the serum Cu levels. Taking together, all these findings suggest that Cu may be a major culprit in the pathogenesis as well as in the severity of the disease.     

Antioxidant status in neonatal jaundice before and after phototherapy

Phototherapy has been related to increased oxidative stress and lipid peroxidation. In the present study, thirty full term jaundiced neonates with appropriate weight were analyzed before and after completion of phototherapy for malondialdehyde (MDA), reduced glutathione (GSH), total thiols, vitamin C and superoxide dismutase (SOD) levels in hemolysate and albumin levels in plasma. These parameters were analyzed in cord blood samples of 20 healthy neonates as control. It was observed that levels of MDA were elevated significantly (p<0.001) in patients as compared to controls and that the levels increased significantly after phototherapy (p<0.001). Levels of SOD were also found to be increased significantly as compared to controls and the levels rose after phototherapy (p<0.001). On the other hand, the levels of non-enzymatic antioxidants such as GSH, total thiols and vitamin C were significantly low (p<0.001) as compared to controls and the levels decreased significantly after phototherapy (p<0.001). The plasma albumin levels also were found to be decreased significantly after phototherapy (p<0.01). Therefore, phototherapy increases oxidative stress and should be used with care.     

Plasma MDA and antioxidant vitamins in diabetic retinopathy

Hyperglycemia and dyslipidemia in diabetes mellitus induce increased lipid peroxidation and peroxyl radical formation, an important mechanism in genesis of microangiopathy. We took up a study on oxidative stress, measured by plasma MDA and antioxidant vitamin status in type − 2 DM patients with and without retinopathy and compared them with a control non-diabetic group. Lipid peroxidation marker MDA was significantly elevated (p < 0.001) in both the diabetic groups whereas, serum vitamin E and vitamin C registered a significant fall (p<0.001) as compared to controls. Our correlation study revealed a significant positive association between plasma MDA with both fasting and 2hr post prandial plasma glucose (r=0.81, p < 0.001, r=0.92, p <0.001) suggesting the role of hyperglycemia in free radical production. Plasma MDA also depicted significant positive relation (p< 0.001) with all lipid parameters except serum HDLc pointing the role of dyslipidemia towards lipid peroxidation. Plasma MDA level was also found to be negatively correlated with both the vitamins (p<0.001, p<0.001) in the study group explaining their protective consumption in the oxidative process prevailing in diabetic retinopathy.     

Association of Inflammatory Biomarker C-Reactive Protein, Lipid Peroxidation and Antioxidant Capacity Marker with HbF Level in Sickle Cell Disease Patients from Chattisgarh

This study was undertaken to determine the association of inflammatory biomarker, oxidative stress and antioxidant capacity marker with fetal haemoglobin (HbF) level among sickle cell trait and sickle cell disease (SCD) patients in Chattisgarh. The study group consisted of 51 SCD (SS) patients with painful episode, 49 SCD (SS) patients with steady state, 50 sickle cell trait (AS) and 50 controls. Malondialdehyde (MDA), CRP, total antioxidant power (FARP), total thiol and HbF levels were quantified. We found a significant positive (p < 0.0001) association between CRP and MDA levels and its inverse association with HbF level in SS patients. We also observed that antioxidant capacity had significantly positively (p < 0.0001) associated with HbF level. The protective effect of HbF was found, because the increase in HbF levels resulted in decrease in lipid peroxidation and inflammation in SCD patients. A decrease in the HbF level and its antioxidant capacity has been associated with the pathogenesis of SCD. These finding may explain the high level of HbF is ameliorating oxidative stress and inflammation in SCD patients.     

Reconvene and Reconnect the Antioxidant Hypothesis in Human Health and Disease

The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality. Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants, including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established. The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency. The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy, diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good.     

Antioxidant Status and Oxidative Stress in the Circulation of Younger and Elderly Human Subjects

Extensive research has demonstrated the protective properties of antioxidants, which scavenge reactive oxygen species and their precursors, as well as up-regulate enzymes involved in the repair of cellular damage. Several case–control studies have showed higher blood levels of antioxidants and decreased oxidative stress in younger individuals when compared with older ones. Cell damage caused by free radicals appears to be a major contributor in aging and degenerative diseases of aging such as cancer, cardiovascular disease, cataracts, compromised immune system, rheumatoid arthritis and brain dysfunction. The objective of this study was to determine the variation of Circulating levels of selected antioxidants (enzymic and non enzymic) and oxidative stress marker in younger and older humans. The results showed that a majority of the younger age group participants showed a significant increase in enzymic and nonenzymic antioxidant status and a decrease in oxidative stress when compared with the older age group.     

Correlation between lipid peroxidation and non-enzymatic antioxidants in pregnancy induced hypertension

The present study was designed to evaluate the lipid peroxidation and non-enzymatic antioxidants in pregnancyinduced hypertension (PIH) compared with healthy normal pregnant and non-pregnant as controls. 75 cases were studied of which 25 were normal healthy controls (Group A), 25 healthy pregnant women (Group B) of third trimester and 25 were PIH (Group C) of the same trimester. In PIH, malondialdehyde a lipid peroxidation product was significantly increased as compared to normal pregnant and non-pregnant controls. The nonenzymatic antioxidants like reduced glutathione, Vitamin-E, Vitamin-C and Vitamin-A were significantly decreased in normal pregnants as compared to controls. A further significant decrease was noticed in PIH compared to normal pregnants. A significant negative correlation was detected between lipid peroxidation and non-enzymatic antioxidant levels. Our study clearly indicates a relationship between elevated lipid peroxidation, decreased non-enzymatic antioxidant in PIH. The measurement of non-enzymatic antioxidants in plasma may be useful predictor of the likely development of PIH.     

Chronic Exposure to Lead: A Cause of Oxidative Stress and Altered Liver Function in Plastic Industry Workers in Kolkata,India

It is well known that chronic exposure of lead leads to adverse health effects. Workers for plastic industry are generally exposed to high concentration of lead as fume, dust, and additive that protect PVC. This study was done on them to find out the detrimental effects of chronic lead exposure on hepatic and hematological toxicity. Blood and 24 h urine sample was collected from 47 plastic industry workers and matched against 42 controls for various parameters. The study group shows significant increase in blood (p < 0.0001) and urinary level of lead (p < 0.0001). Hemoglobin levels were significantly decreased (p < 0.0001), and the liver enzymes like ALP, ALT, AST and y-GT were significantly increased (p < 0.0001) in all cases exposed for >10 years. Serum lipid peroxide by quantitative assay of thiobarbituric acid reactive substances was also found increased in the study group (p < 0.0001). The observations point towards the acute health risk faced by plastic industry workers, in whom chronic exposure to lead increases the absorption and accumulation, over a period of time, of this highly toxic element in their body. This increases oxidative stress, causes metabolic damage to RBC and cell membranes, and also suggests necrosis of liver cell, hepatocellular injury and presence of space occupying lesions. Considering the data immediate health and hygiene monitoring and proper rehabilitation for the suffering population seem to be of paramount need in plastic industry to minimize occupational hazards.     

Hypomagnesaemia in type-2 diabetes mellitus patients: A study on the status of oxidative and nitrosative stress

This study was undertaken to evaluate the levels of plasma magnesium, lipid peroxides, nitric oxide end products, erythrocyte membrane lipid peroxides, erythrocyte reduced glutathione and erythrocyte superoxide dismutase activity in type-2 diabetes mellitus patients. 60 patients with type-2 diabetes mellitus and 30 healthy control subjects were included in this study. Among 60 type-2 diabetic patients, 30 patients were without complication and 30 patients were with various complications. Decreased levels of plasma magnesium, erythrocyte reduced glutathione and erythrocyte superoxide dismutase activity while increased levels of plasma lipid peroxides, nitric oxide end products and erythrocyte membrane lipid peroxides were observed in patients with type-2 diabetes mellitus. We propose that, under the shadow of hypomagnesaemia, there is excessive production of reactive oxygen species and reactive nitrogen species as reflected by elevated lipid peroxides and nitric oxide end products concomitant with dwindled antioxidants and suggest their association with late complications in type-2 diabetes mellitus.     

Monitoring oxidative stress in patients with non-alcoholic and alcoholic liver diseases

Ethanol-induced liver injury may be linked, at least partly, to an oxidative stress resulting from increased free radical production and/or decreased antioxidant defence. Distinguishing alcoholic and non-alcoholic liver disease has important implications. This study looked at the possible changes between alcoholic and non-alcoholic liver diseases by examining the presence of oxidative damage, as monitored by several parameters relating to oxidative stress. Lipid peroxides concentration, superoxide dismutase activity and glutathione S-transferase activity increased, where as glutathione content, glutathione peroxidase activity and glutathione reductase activity decreased among the tested subjects in comparison to normal healthy group. Determination of these parameters may be valuable in the evaluation of liver disease. However, oxidative stress related enzymes and non-enzymes can not be utilized as a marker for alcoholic liver diseases, as these parameters responded in the same way after liver is damaged irrespective of their cause. Their level may help in determining the degree of liver damage. Degree of oxidative injury was similar in patients with non-alcoholic liver disease and in moderate drinkers; while significantly higher in heavy drinkers. The differences between the groups might be based on the type of liver pathological condition rather than its etiology (i.e. alcohol and non alcohol related causes).     

Association of Oxidative Stress with Disease Activity and Damage in Systemic Lupus Erythematosus: A Cross Sectional Study from a Tertiary Care Centre in Southern India

To study oxidative stress in systemic lupus erythematosus (SLE) by estimating serum oxidised LDL (OxLDL), 8-hydroxy-2′-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and total anti-oxidant status and to correlate with SLE disease activity and disease damage. Eighty SLE patients satisfying the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) 2012 criteria and 80 healthy controls were studied. Exclusion criteria were infections, renal insufficiency, other connective tissue diseases, drug-induced lupus, smoking, alcohol consumption. Disease activity was measured by SLE disease activity index-2 K (SLEDAI), disease damage was quantified by SLICC-Damage Index (SDI). Sera was tested for OxLDL, 8-OHdG, and total antioxidant status (TAS) by double-antibody sandwich ELISA; MDA measured by Colorimetric assay. Oxidative stress markers were compared between group1- controls, group 2-mildly active SLE (SLEDAI ≤ 5), group 3- moderate to highly active SLE (SLEDAI ≥ 6). SLE patients had significantly higher MDA, 8-OHdG and lower TAS when compared to healthy controls, while OxLDL was similar in the three groups. MDA, 8-OHdG were significantly higher, TAS lower in group 3 compared to group 2. MDA had positive correlation with SLEDAI, TAS negatively correlated with SLEDAI. SLE with neuropsychiatric manifestations, vasculitis, anti-sdDNA antibodies had higher MDA, MDA/TAS ratio. SLE patients with thrombocytopenia, and vasculitis had higher OxLDL. Only OxLDL was significantly higher in those patients who have SDI > 1. SLE patients have increased oxidative stress measured by increases in MDA, 8-OHdG, and lower total antioxidant status that was associated with disease activity and some disease manifestations. However only OxLDL was associated with damage.     

Evaluation of Oxidative Stress and DNA Damage in Benign Prostatic Hyperplasia Patients and Comparison with Controls

In the present study, oxidative stress and lymphocytic DNA damage in both pre-op and post-op benign prostrate hyperplasia (BPH) patients with age >50 years was evaluated and compared with normal healthy subjects (controls- without any evidence of disease) of the same sex and age group. From December 2007 to November 2009, oxidative stress in 45 BPH patients were evaluated both before (pre-op patients) and after 7 days of surgery (post-op patients) in terms of measurements of plasma levels of (1) various anti-oxidative enzymes, (2) non-enzymatic antioxidants and (3) malondialdehyde which is a product of lipid peroxidation. The lymphocyte DNA damage was also evaluated by single cell alkaline gel electrophoresis in terms of tail length migration in these patients. These values were compared with their respective control subjects of similar sex and age group. The activities of antioxidant enzymes and the levels of antioxidant, reduced glutathione were found significantly decreased (p < 0.05) in serum samples of pre-operative group of BPH patients as compared to the controls. These altered parameters increased significantly (p < 0.05) and returned to their near normal control values, but not up to baseline values, in post operative patients i.e. after the cancer load was decreased by surgery. Lymphocytic DNA damage was found to be significantly increased in pre-op group as compared to controls and was reduced after surgery in post-op group. The present study therefore, shows significantly increased levels of oxidative stress and DNA damage in BPH patients which were reduced after removal of tumour load. Thus oxidative damage plays an important role in prostate tumourogenesis and timely management of oxidative stress can be of importance in preventing the occurrence of BPH.     

红壤中针铁矿的铝替代及其与土壤发育的关系

在研究的红壤类土壤样品中普遍存在着针铁矿的铝同晶替代作用,供试样品中针铁矿铝替代量为0.14％～27.21％(摩尔百分数),平均为8.77％。红壤亚类、黄红壤亚类和黄壤亚类平均依次为10.32％、9.79％、1.30％,其中红壤、黄红壤亚类与黄壤亚类之间差异明显,这反映了成土条件的差异。土壤中针铁矿的铝替代量与粘粒中铁的游离度正相关,与土壤粉砂粘粒比负相关,说明针铁矿中铝替代量随土壤发育的增加而增加。     

Evaluation of Oxidative Stress in Type 2 Diabetes Mellitus and Follow-up Along with Vitamin E Supplementation

Increased oxidative stress is a widely accepted participant in the development and progression of diabetes and its complications. The present study has been undertaken to evaluate oxidative stress in type 2 diabetes mellitus and effect of vitamin E supplementation on oxidative stress. In all 120 subjects were enrolled in the present study, 40 subjects are age and sex matched controls. Test group comprised of clinically diagnosed (n = 80) type 2 diabetic patients. Biochemical parameters like serum MDA, nitric oxide, superoxide dismutase, erythrocyte reduced glutathione and platelet aggregation were analyzed in control and diabetic group. Test group is further categorized as Group I (n = 40) diabetics were treated by only hypoglycemic drugs and Group II (n = 40) diabetics were treated by hypoglycemic drugs with vitamin E supplementation. All above biochemical parameters were again reassessed after 3 months follow-up in both group and its values were compared with its respective baseline levels. The study shows, reduction of oxidative stress, improvement in antioxidant enzymes and endothelial dysfunction in group II, those were on treatment of hypoglycemic drugs along with vitamin E supplementation. Hence the present study may conclude that vitamin E supplementation along with hypoglycemic drugs may be beneficial to type 2 DM patients to minimize vascular complications.     

Some oxidative stress related parameters in patients with head and neck carcinoma

Forty cases of head and neck cancer were studied for plasma superoxide dismutase, malondialdehyde and thiol levels and results were compared with a group of forty normal healthy volunteers. Mean plasma superoxide dismutase activity was not found to be altered while malondialdehyde concentration was significantly higher when compared with the control group. On the other hand, mean thiol level was significantly lowered. The data suggests increased level of oxidative stress in patients with head and neck cancer.     

Correlations of Insulin Resistance and Serum Testosterone Levels with LH:FSH Ratio and Oxidative Stress in Women with Functional Ovarian Hyperandrogenism

Functional ovarian hyperandrogenism (FOH) is a form of polycystic ovary syndrome (PCOS) characterized by elevated circulating levels of androgens derived from the ovary. Insulin resistance (IR) is the most common etiological factor in women with FOH. IR causes the generation of increased oxidative stress (OS) and diminished antioxidant status. OS is directly correlated with both IR and testosterone levels, which consequently contribute to endocrine and biochemical alterations in FOH women. In the current study, elevations in total testosterone, free testosterone and luteinizing hormone (LH) levels accompanied by a decrease in follicle stimulating hormone (FSH) level leading to higher LH:FSH ratio were the prominent endocrine changes observed in women with FOH. A significant increase in fasting blood levels of glucose and insulin, as well as an elevated IR were also seen in FOH women, as compared to their age matched controls. Women with FOH have higher pro-oxidant and lower anti-oxidant levels in blood than their age matched controls. In FOH women, elevations in LH:FSH ratio and OS are correlated more with hyperandrogenemia than with IR. Of the androgens, free rather than total testosterone has better positive correlations with elevated LH:FSH ratio and OS, and hence, the former is a better predictive marker for the development of biochemical PCOS in women with FOH.     

Effect of Turmeric and its Active Principle Curcumin on T<Subscript>3</Subscript>-Induced Oxidative Stress and Hyperplasia in Rat Kidney: A Comparison

The present study was designed to compare the potential of turmeric and its active principle curcumin on T₃-induced oxidative stress and hyperplasia. Adult male Wistar strain rats were rendered hyperthyroid by T₃ treatment (10 μg · 100 g⁻¹ · day⁻¹ intraperitoneal for 15 days in 0.1 mM NaOH) to induce renal hyperplasia. Another two groups were treated similarly with T₃ along with either turmeric or curcumin (30 mg kg⁻¹ body weight day⁻¹ orally for 15 days). The results indicate that T₃ induces both hypertrophy and hyperplasia in rat kidney as evidenced by increase in cell number per unit area, increased protein content, tubular dilation and interstitial edema. These changes were accompanied by increased mitochondrial lipid peroxidation and superoxide dismutase activity without any change in catalase activity and glutathione content suggesting an oxidative predominance. Both turmeric and curcumin were able to restore the level of mitochondrial lipid peroxidation and superoxide dismutase activity in the present dose schedule. T₃-induced histo-pathological changes were restored with turmeric treatment whereas curcumin administration caused hypoplasia. This may be due to lower concentration of curcumin in the whole turmeric. Thus it is hypothesized that regulation of cell cycle in rat kidney by T₃ is via reactive oxygen species and curcumin reveres the changes by scavenging them. Although the response trends are comparable for both turmeric and curcumin, the magnitude of alteration is more in the later. Turmeric in the current dose schedule is a safer bet than curcumin in normalizing the T₃-induced hyperplasia may be due to the lower concentration of the active principle in the whole spice.     

Oxidative stress and antioxidant status in patients with chronic myeloid leukemia

Chronic myeloid leukemia is a myeloproliferative disorder with a unique rearrangement, the Philadelphia chromosome. Oxidative stress, a pervasive condition of an increased number of reactive oxygen species, is now recognized to be prominent feature of various diseases and their progression. Thus antioxidants, which control the oxidative stress state, represent a major line of defense regulating overall true state of health. The relationship between antioxidants status and levels of well-known markers of oxidative stress that are measured as lipid peroxides and oxidized proteins reflect better health indices and postures. The aim of this study was to evaluate the role of oxidative stress in pathophysiology of Chronic myeloid leukemia by measuring the circulating plasma lipid peroxide levels in terms of malonyldialdehyde, total lipid hydroperoxide and oxidized proteins as protein carbonyl whereas antioxidant status were estimated in terms of reduced glutathione and total thiol in plasma of Chronic myeloid leukemia patients. The present study included 47 Chronic myeloid leukemia patients and 20 age-and sex-matched healthy subjects. Out of 47 Chronic myeloid leukemia patients, 31 were in chronic phase (CML-CP) and 16 in accelerated phase (CML-AP). The median age of Chronic myeloid leukemia patients was 33 years and that of controls was 32 years. Oxidative stress and antioxidant status in plasma were evaluated by spectrophotometric procedures. There was a significant increase (p<0.05) in plasma malonyldialdehyde, total lipid hydroperoxide and protein carbonyl levels in Chronic myeloid leukemia patients as compared to healthy subjects. Our results also showed that plasma malonyldialdehyde and protein carbonyl levels were markedly elevated (p<0.05) in both chronic phase (CML-CP) and accelerated phase (CML-AP) as compared to healthy volunteers. Antioxidant status was found to be significantly decreased (p<0.05) in Chronic myeloid leukemia patients and its phases as compared to healthy participants. It could be concluded that oxidative stress may be associated with the pathophysiology of Chronic myeloid leukemia.     

北方13省1982年～1999年植被变化及其与气候因子的关系

植被覆盖变化研究在土地利用/覆盖变化研究中占据着的重要内容。北方13省气候的地域差异性和过渡性明显，植被类型多样，是我国境内对全球变化反应较为敏感的生态系统地带。研究该地区植被变化特征及其与气候因子的响应关系有助于深入理解这一地区土地利用/覆盖变化总体特征以及对区域及全球气候和环境变化的影响。本文基于NOAA/AVHRR NDVI数据，气候和土地覆盖数据对北方13省地区1982年～1999年植被动态变化及其与气候因子的关系进行了分析。结果表明18年间研究区植被总体呈现增加趋势，植被平均NDVI生长季增加了11.69%。春、秋两季植被增加趋势最为明显。植被变化与气温相关性显著而与降水无显著相关，气温升高引起的生长期提前和生长季延长是植被增加的一个重要原因；人类活动等非气候因子是影响植被变化的另一个重要原因，人类一方面通过合理有效的措施改善植被状况，另一方面不合理的活动又导致部分地区植被严重退化；研究区植被像元的NDVI有18.24%的面积显著增加，0.24%显著减少，其中耕地、草甸、草原和落叶阔叶林四种植被类型植被变化最为显著。     

Differential Expressions of p53, p53R2, hRRM2 and PBR in Chronic Lymphocytic Leukemia: A Correlation with Intracellular Cholesterol

Regulation of intracellular cholesterol homeostasis exists under balance between intracellular biosynthesis and uptake from extracellular origin by cell surface transport proteins. Expected role of cholesterol on either tumor suppressor gene and/or DNA synthesis has been aimed in the present study to explore intracellular cholesterol homeostasis in CLL subjects. Higher expressions of p53R2 (p53 dependent subunit of ribonucleotide reductase) and p53 were found in lymphocytes of chronic human lymphocytic leukemia as comparison to their normal counterparts. Inverse relation was found with p53 independent R2 subunit (in human hRRM2) of ribonucleotide reductase, which was found to be decreased from its control group. More expression of peripheral type benzodiazepine receptor, a cholesterol transporter, was noticed in isolated nuclear fraction with simultaneous increase of cholesterol concentration in cytoplasmic and nuclear compartments. A parallel increase of cholesterol in cell nucleus with increased p53R2 expression shows priority of the involvement of cholesterol in the process of cell replication.