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71.
Heroin use and addiction pose serious risks and side effects due to overdose. Quantification of heroin in biological samples is challenging due to rapid deacetylation of heroin to its active metabolites. In this study, we report the quantification of metabolic degradation of heroin by-products in biological urine samples. The presence of the drug was monitored after oral administration of heroin at different time intervals. Various biophysical techniques, such as high performance liquid chromatography (HPLC) and mass spectrometry (MS) were used to evaluate the presence of the drug. A competitive fluorescence based immunoassay was developed with a limit of detection (LOD) up to 0.01 ng mL−1 and the IC50 value was 0.1 ng mL−1, while the dipstick assay shows a LOD up to 5 ng mL−1. Rapid detection of narcotic drugs was carried out for biological urine samples collected at various time points. Validation of the developed dipstick was carried out for the standard as well as the spiked urine samples by fluorescence based immunoassay (FIA), using anti-morphine antibodies. A strong correlation (R = 0.94) was obtained between the developed dipstick and FIA assay for biological urine samples collected at various time points. The developed immunochromatographic dipstick is highly sensitive, field applicable and cost effective, and can serve as a first choice for the monitoring of narcotic drugs in blood, urine and saliva in drug addicts and athletes.

Pathway of heroin degradation post oral administration in mice.  相似文献   
72.
This study was undertaken to resolve existing controversies with respect to the detection of IgA HIV-1-specific mucosal antibodies in infected individuals. External secretions, including tears, nasal, rectal, and vaginal washes, saliva, semen, urine, and sera were obtained from 50 HIV-1-infected individuals and 20 controls using collection procedures that minimize the irritation of mucosal surfaces. Levels of total and antigen (gp120 and gp160)-specific antibodies of the IgG and IgA isotypes were measured by assays that proved reliable in a large multicenter study: quantitative ELISA and chemiluminescence-enhanced Western blot analyses. Although the levels of total IgG and IgA were increased or remained unchanged in body fluids of HIV-1-infected individuals as compared to the controls, HIV-1-specific IgA antibodies were either absent or present at low levels even in secretions with characteristically high relative contents of total IgA vs. IgG (saliva, tears, and rectal and nasal washes). In these secretions, HIV-1-specific IgG antibodies dominated. In assessing levels and frequency of detection of IgG antibodies, both female and male genital tract secretions, urine, and nasal wash were preferable to parotid saliva and especially to rectal wash. External secretions contained IgG antibodies to gp160> gp120> gp41 and p24; when present, IgA antibodies were predominantly directed at gp160. Analyses of peripheral blood antibody-secreting cells (ASC) isolated from the same individuals paralleled these serological findings: gp160-specific IgG-secreting ASC were dominant. Therefore, in striking contrast to other mucosally encountered microbial infections, HIV-1 does not induce vigorous specific IgA responses in any body fluid examined or in ASC in peripheral blood.  相似文献   
73.
Hyperimmune γ-globulins have proven efficacious in the prevention and treatment of viral infections, including those caused by hepatitis A and B viruses, cytomegalovirus, parvovirus. Interest in the prevention and/or treatment of infections caused by human immunodeficiency virus (HIV) has led to clinical trials with anti-HIV immune plasma and purified immune globulin prepared from donors who are actively infected with HIV. The handling and fractionation of this or other infectious plasma requires the construction and operation of virus containment facilities designed to protect fractionation employees and the immediate environment. This requirement would be reduced substantially by applying virucidal procedures prior to or during plasma pooling. We have shown that heating plasma at 56°C for 1 h followed by treatment with 1% tri(n-butyl) phophate (TNBP) and 1% Triton X-100 for 4 h at 30°C resulted in the inactivation of ≥ 1012.1 tissue culture infectious doses (TCID50) of HIV. With this treatment, the recovery of IgG was 87±3%. Fractionation of treated plasma by cold ethanol precipitation proceeded normally, and overall recovery, purity, and potency against selected viral markers were unaffected. The additional treatment of plasma with 15 g/l Aerosil for 4 h at 45 °C removed 104.5 TCID50 of HIV but resulted in substantial IgG losses both prior to and following fractionation. We conclude that potentially infectious plasma can be treated at 56°C for 1 h and by TNBP/Triton X-100 at 30°C for 4 h prior to fractionation. These steps appear sufficient to assure safety and to permit routine fractionation of plasma. Aerosil treatment, under the condition evaluated, was less satisfactory, although lower concentrations or temperatures than those evaluated may prove advantageous.  相似文献   
74.
Isolated growth hormone (GH) deficiency (IGHD) is a rare cause of short stature. The same mutation of the gene encoding the growth hormone-releasing hormone receptor (GHRHR) has been identified as the basis for IGHD in three families from the Indian subcontinent. The prevalence and heterogeneity of defects in the GHRHR gene are not known. Twenty-two dwarf members of a large, extended kindred containing at least 105 affected members with autosomal recessive short stature underwent extensive endocrine evaluation, which confirmed markedly reduced or undetectable serum concentrations of GH that did not increase in response to different stimuli. DNA sequences of the 13 exons and intron-exon boundaries of the GHRHR gene were determined in an index patient. A novel homozygous 5' splice site mutation (G-->A at position +1) in IVS1 was found. Thirty of the affected subjects tested were homozygous for this mutation, and 64 clinically unaffected patients were either heterozygous for the mutation (n = 41, including 9 obligate carriers) or homozygous for the wild-type sequence (n = 23). We describe a novel mutation in the GHRHR gene as cause of dwarfism in the largest kindred with familial IGHD described to date.  相似文献   
75.
Toxoplasma peritonitis in a patient with acquired immunodeficiency syndrome   总被引:2,自引:0,他引:2  
Toxoplasma gondii was identified in a stained slide preparation of, and isolated from, peritoneal fluid specimens obtained from a patient with the acquired immunodeficiency syndrome (AIDS). At the time of admission to the hospital, the patient's serologic tests were positive for Toxoplasma. Toxoplasma was isolated from samples of the patient's blood by mouse inoculation. Findings of newly developed methods for diagnosis of the presence of T gondii in body fluids by assay for Toxoplasma-specific antigen and by use of a DNA probe were positive.  相似文献   
76.
The antihypertensive efficacy of bevantolol, a selective beta 1-adrenoreceptor antagonist, was evaluated in 17 patients with essential hypertension, using continuous ambulatory intraarterial blood pressure (BP) monitoring. The study compared a twice-daily regimen (titrated dose of 200 to 600 mg/day) with the same amount given in a single daily dose. Within-patient comparisons of mean hourly systolic and diastolic BPs and heart rate showed a highly significant effect with twice-daily therapy (p less than 0.001) for all of the 24 hours. Similar significant results were obtained with a single morning dose. There was no difference between the pattern or extent of BP reduction with the 2 regimens. The decrease in BP after bevantolol persisted during the physiologic tests (rest, tilt, isometric and dynamic exercise). Four patients developed minor side effects with the single morning dose, and only 1 patient with the twice-daily regimen. These effects included tiredness, fatigue and dizziness. Unlike pure beta-blocking agents, bevantolol controlled the early morning increase in BP, lending support to the belief that it possesses vasodilatory properties in addition to beta blockade. These results suggest that bevantolol may be useful as first-line therapy in a once-daily dosage for the treatment of essential hypertension.  相似文献   
77.
Activation of fibronectin gene expression by hepatitis B virus x antigen   总被引:5,自引:0,他引:5  
The development of fibrosis and cirrhosis during chronic hepatitis B virus (HBV) infection correlates with the persistent expression of HBV x antigen (HBxAg), which acts in part, by stimulating selected signal transduction pathways, including nuclear factor kappa B (NF-kappa B). To identify NF-kappa B responsive genes that are differentially expressed in HBxAg-positive cells, HepG2 cells were stably transfected with HBxAg, and then with pZeoSV2 or pZeoSV2-I kappa B alpha. When RNAs from each culture were compared by PCR-select cDNA subtraction, fibronectin (FN) mRNA was shown to be strongly down-regulated by I kappa B alpha. Up-regulated expression of FN and co-expression between FN and HBxAg were observed in liver sections from HBV carriers that were stained for HBxAg and analysed for FN mRNA by in situ hybridization (ISH). In liver cell cultures, HBxAg increased the levels of FN mRNA and protein. This was because of the HBxAg-mediated trans-activation of the FN promoter, which was NF-kappa B-dependent. HBxAg also antagonized the repression of the FN promoter by the tumour suppressor, p53. Hence, the FN gene may be a natural target for HBxAg trans-activation, perhaps through activation of NF-kappa B and inactivation of p53, thereby contributing to the accumulation of FN in the liver over the course of chronic HBV infection.  相似文献   
78.
A cDNA clone representing the mRNA coding sequence of the fusion glycoprotein (F) gene of human respiratory syncytial virus (RSV) was constructed and inserted into the thymidine kinase gene of vaccinia virus (WR strain) under the control of a vaccinia virus promoter. The resulting recombinant vaccinia virus, vaccinia F, expressed the F1 and F2 cleavage products (48 and 20 kDa, respectively) of the F glycoprotein in cell culture. F1 and F2 were indistinguishable from their authentic RSV counterparts with respect to glycosylation, disulfide linkage, electrophoretic mobility, cell-surface expression, and antigenic specificity. Cotton rats infected intradermally with vaccinia F developed a high titer of serum F-specific antibodies, which neutralized infectivity of RSV. This neutralizing antibody response exceeded that induced by infection of the respiratory tract with RSV and was 6-fold higher than that induced by vaccinia G, a recombinant vaccinia virus that expressed the RSV G glycoprotein gene. Immunization with vaccinia F stimulated almost complete resistance to replication of RSV in the lower respiratory tract as well as significant resistance in the upper respiratory tract. The degree of resistance conferred by vaccinia F exceeded that induced by vaccinia G.  相似文献   
79.
The gene encoding sortilin receptor 1 (SORL1) has been associated with Alzheimer's disease risk. We examined 15 SORL1 variants and single nucleotide polymorphism (SNP) set risk scores in relation to longitudinal verbal, spatial, memory, and perceptual speed performance, testing for age trends and sex-specific effects. Altogether, 1609 individuals from 3 population-based Swedish twin studies were assessed up to 5 times across 16 years. Controlling for apolipoprotein E genotype (APOE), multiple simple and sex-moderated associations were observed for spatial, episodic memory, and verbal trajectories (p = 1.25E-03 to p = 4.83E-02). Five variants (rs11600875, rs753780, rs7105365, rs11820794, rs2070045) were associated across domains. Notably, in those homozygous for the rs2070045 risk allele, men demonstrated initially favorable performance but accelerating declines, and women showed overall lower performance. SNP set risk scores predicted spatial (Card Rotations, p = 5.92E-03) and episodic memory trajectories (Thurstone Picture Memory, p = 3.34E-02), where higher risk scores benefited men's versus women's performance up to age 75 but with accelerating declines. SORL1 is associated with cognitive aging, and might contribute differentially to change in men and women.  相似文献   
80.
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