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151.
Proteins secreted into the culture medium byMycobacterium tuberculosis (M. tb) are shown to be source of antigens of immunodiagnostic interest. Anin vitro released 31 kDa antigen ESAS-7F isolated fromM.tb H37Ra culture filtrate by salt precipitation, SDS-PAGE and cation exchange fast protein liquid chromatography (FPLC) was shown earlier to be a diagnostically important antigen fraction. In this report, we describe the isolation of ESAS-7F antigen using monospecific antibody coupled to sepharose CL-4B column. The percentage recovery of ESAS-7F antigen using affinity chromatography was approximately 8% of the total ES antigen proteins compared to 0.05% obtained by conventional purification steps using salt precipitation, SDS-PAGE and FPLC. Similar seroreactivity was observed by the antigen isolated by both the methods in indirect ELISA. Affinity chromatography helped in an increased recovery of ESAS-7F antigen and obviates the need for time consuming conventional purification steps.  相似文献   
152.
The negative interference by bilirubin in serum creatinine estimation by Jaffe’s kinetic method is well known. Several approaches have been suggested to overcome this interference. In this article three different creatinine kits (Jaffe’s kinetic method) have been tested for bilirubin interference and its rectification using two simple approaches. The performance of three kits (A, B and C) supplied by three different manufacturers was tested using IQC and EQAS sera and pooled serum with added bilirubin. To overcome the bilirubin interference two approaches viz. NaOH preincubation and TCA precipitation were used. Bilirubin did interfere in creatinine estimation after a certain level (2.3 mg/dl). However, both NaOH preincubation and TCA precipitation approach rectified this interference. The performance of kit A was better than kit B and C. All the three kits showed bilirubin interference upon increasing the bilirubin concentration but kit A performed better than kit B and C. However, NaOH incubation and TCA precipitation methods overcame this interference to a great extent.  相似文献   
153.
Background: Autoimmune thyroid disease (AITD), a common organ specific autoimmune disorder is seen mostly in women between 30–50 yrs of age. Thyroid autoimmunity can cause several forms of thyroiditis ranging from hypothyroidism (Hashimoto’s thyroiditis) to hyperthyroidism (Graves’Disease). Prevalence rate of autoimmune mediated hypothyroidism is about 0.8 per 100 and 95% among them are women. Graves’ disease is about one tenth as common as hypothyroidism and tends to occur more in younger individuals. Both these disorders share many immunologic features and the disease may progress from one state to other as the autoimmune process changes. Genetic, environmental and endogenous factors are responsible for initiation of thyroid autoimmunity. At present the only confirmed genetic factor lies in HLA complex (HLA DR-3) and the T cell regulatory gene (CTLA 4). A number of environmental factors like viral infection, smoking, stress & iodine intake are associated with the disease progression. The development of antibodies to thyroid peroxidase (TPO) thyroglobulin (TG) and Thyroid stimulating hormone receptor (TSH R) is the main hallmark of AITD. Circulating T Lymphocytes are increased in AITD and thyroid gland is infiltrated with CD4+ and CD8+ T Cells. Wide varieties of cytokines are produced by infiltrated immune cells, which mediate cytotoxicity leading to thyroid cell destruction. Circulating antibodies to TPO and TG are measured by immunofluorescense, hemagglutination, ELISA & RIA. TSHR antibodies of Graves’ disease can be measured in bioassays or indirectly in assays that detect antibody binding to the receptor.  相似文献   
154.
Fructose developed a pinkish orange chromogen on treatment with o-cresol: 70% sulphuric acid at 32°C for 15 minutes with a λ max of 500nm. Fructose was 185 times more chromogenic than glucose. Total carbohydrate and fructose values in protein-free filtrate of normal serum samples were in the range, 55.4–86.3 mg/dl and 1.55–3.29 mg/dl, respectively. In diabetes, the observed values were 197–354 mg/dl and 2.91–6.81 mg/dl, respectively.  相似文献   
155.
A variety of laboratory tests are available to assist in the diagnosis of alcohol consumption and related disorders. The levels of intake at which laboratory results become abnormal vary from person to person. Laboratory tests are particularly useful in settings where cooperativeness is suspected or when a history is not available. Several biochemical and hematological tests, such as γ-glutamyltransferase (GGT) activity, aspartate aminotransferase (AST) activity, high-density lipoprotein cholesterol (HDL-C) content of serum, and erythrocyte mean corpuscular volume (MCV) are established markers of alcohol intake. Their validity as markers is based largely on correlations with recent intake at a single time point and on decreases in elevated values when heavy drinkers abstain from alcohol. These readily available laboratory tests provide important prognostic information and should be integral part of the assessment of persons with hazardous alcohol consumption. There are several other markers with considerable potential for more accurate reflection of recent alcohol intake. These include carbohydrate deficient transferrin, β-hexosaminidase, acetaldehyde adducts and the urinary ratio of serotonin metabolites, 5-hydroxytryptophol and 5-hydroxyindoleacetic acid. These markers provide hope for more sensitive and specific aids to diagnosis and improved monitoring for intake.  相似文献   
156.
Carbohydrate deficient transferrin (CDT) is one of the conventional markers for chronic alcohol consumption, is used by researchers and clinicians. A number of enzymes are affected by ethanol intake. The induction or inhibition of sialyl transferase and plasma sialidase may be involved in the CDT level elevation. An alteration of protein transport during post-translational modification could be a primary mechanism in the impairment of protein metabolism associated with chronic alcohol abuse. Transferrin being a steroid responsive protein, sex-based hormonal variations might contribute to the lower sensitivity of CDT. Varying hormonal statuses such as pregnancy, use of contraceptives, menopause/ menstrual cycle can alter iron homeostasis in women. CDT levels are markedly affected by iron homeostasis. Several CDT assay methods appeared promising, but it is not readily apparent which technique is the most accurate. Moreover, false-positive results of CDT have been reported in non-alcohol related hepatic failure and in rare conditions. Therefore clinical interpretation of CDT needs careful assessment in patients with alcohol-related or non-alcohol-related health disorders.  相似文献   
157.
Aluminum and alcohol, both are well-accepted neurotoxin. The plausible mechanisms for their neurotoxicity are also common. Therefore, the effect of ethanol on aluminum induced biochemical changes in rat brain is being studied. In the present study, ethanol exposure significantly affected the aluminum and protein content of brain. The activities of acid phosphatase and alkaline phosphatase were also changed. Aluminum exposure, on the other hand, contributed significantly in the alterations of aluminum content, acid phosphatase acivity and aspartate aminotransferase activity. Though ethanol co-exposure significantly influenced the aluminum load of brain, the interactions of these two neurotoxins were found to be significant only in case of acid phosphatase activity of brain. Therefore, it can be suggested that general neurotoxicity produced by aluminum is not modified by ethanol. However, the aluminum load caused by aluminum exposure, may be influenced by ethanol co-exposure.  相似文献   
158.
Two silkworm strains viz, B20 A (high cocoon shell ratio) and C.Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygosis. Both bulked segregant analysis(BSA) and near isogenic lines (NIL) studies were done to identify the RFLP markers closely linked to cocoon shell parameters. Three hundred and fifty-two random clones were identified as the low copy number sequence and used for identification of Restriction Fragment Length Polymorphic (RFLP) marker linked to cocoon weight and cocoon shell character. In the bulk segregant analysis, DNA from the parents (B20 A, C.Nichi), F1 and F2 progeny of high shell ratio (HSR) and low shell ratio (LSR) were screened for hybridization with the random clones. Polymorphic banding pattern achieved through southern hybridization with different probes indicated the probable correlation of polymorphism with high and low cocoon shell character which are possible landmarks in identifying the putative marker(s) for the cocoon shell character. Out of the 100 probes tried with parents, F1, F2 and their bulks, 10 probes were found to be closely linked to cocoon shell characters.  相似文献   
159.
Vegetables are important constituents of the human diet. Heavy metals and nitrate are among the major contaminants of vegetables. Consumption of vegetables and fruits with accumulated heavy metals and nitrate has the potential to damage different body organs leading to unwanted effects. Breeding vegetables with low heavy metal and nitrate contaminants is a cost-effective approach. We investigated 38 water spinach genotypes for low Cd and nitrate co-accumulation. Four genotypes, i.e. JXDY, GZQL, XGDB, and B888, were found to have low co-accumulation of Cd (<0.71 mg/kg dry weight) and nitrate (<3100 mg/kg fresh weight) in the edible parts when grown in soils with moderate contamination of both Cd (1.10 mg/kg) and nitrate (235.2 mg/kg). These genotypes should be appropriate with minimized risk to humans who consume them. The Cd levels in the edible parts of water spinach were positively correlated with the concentration of Pb or Zn, but Cd, Pb, or Zn was negatively correlated with P concentration. These results indicate that these three heavy metals may be absorbed into the plant in similar proportions or in combination, minimizing the influx to aerial parts. Increasing P fertilizer application rates appears to prevent heavy metal and nitrate translocation to shoot tissues and the edible parts of water spinach on co-contaminated soils.  相似文献   
160.
We aimed to assess whether measuring carotid intima-media thickness (CIMT) and oxidative stress markers such as protein carbonyls, malondialdehyde, nitrate and glutathione in plasma of elderly patients without and with coronary artery disease (CAD) identifies early risk for CAD. A total of 50 cases with cardiovascular risk factors over the age of 60 years without CAD, and 50 patients with angiographically documented CAD over the age of 60 years were included in the study. Control group consists of 200 healthy individuals without the risk factors. Demographic details were obtained from all the subjects and CIMT measured by high frequency ultrasound and oxidative stress markers such protein carbonyls, malondialdehyde and total glutathione were determined in plasma by spectrophotometric methods. The distribution of cardiovascular risk factors in without CAD and CAD cases were smokers (16 vs 56 %), hypertension (26 vs 64 %), diabetes (16 vs 56 %) and dyslipidemia (18 vs 58 %) and positive family history (4 vs 38 %). None of the control group had any cardiovascular risk factors. Among the CAD cases, 16 % had single vessel disease, 44 % had double vessel disease and 40 % had triple vessel disease. The CIMT was significantly increased in CAD cases as compared to cases without CAD and healthy controls. On the other hand, CIMT was significantly increased in cases without CAD as compared to healthy controls. CIMT also increased with the duration of diabetes in patients without CAD and severity of disease in CAD cases. The levels of oxidants like plasma malondialdehyde, protein carbonyls, were significantly elevated and antioxidant glutathione levels and nitrate levels were significantly reduced in cases with and without CAD as compared to healthy controls. Oxidative stress markers and CIMT was found to be significantly increased in patients with cardiovascular risk factors like diabetes, family history of CAD, dyslipidemia, hypertension and smoking when compared to patients without risk factors. In patients with diabetes, CIMT increased as duration of disease increases and also in poorly controlled diabetes. In CAD group, when number of vessel involvement (severity of coronary disease) increases, the CIMT also increases confirming that CIMT is a quantifiable risk factor for CAD.  相似文献   
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