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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   
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Clinical Rheumatology - Consensus on treatment of idiopathic inflammatory myositis (IIM), particularly with regard to flares and interstitial lung disease (ILD), does not exist. We studied the...  相似文献   
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Purpose

Describe CYP2C19 sequencing results in the largest series of clopidogrel-treated cases with stent thrombosis (ST), the closest clinical phenotype to clopidogrel resistance. Evaluate the impact of CYP2C19 genetic variation detected by next-generation sequencing (NGS) with comprehensive annotation and functional studies.

Methods

Seventy ST cases on clopidogrel identified from the PLATO trial (n =?58) and Mayo Clinic biorepository (n =?12) were matched 1:1 with controls for age, race, sex, diabetes mellitus, presentation, and stent type. NGS was performed to cover the entire CYP2C19 gene. Assessment of exonic variants involved measuring in vitro protein expression levels. Intronic variants were evaluated for potential splicing motif variations.

Results

Poor metabolizers (n =?4) and rare CYP2C19*8, CYP2C19*15, and CYP2C19*11 alleles were identified only in ST cases. CYP2C19*17 heterozygote carriers were observed more frequently in cases (n =?29) than controls (n =?18). Functional studies of CYP2C19 exonic variants (n =?11) revealed 3 cases and only 1 control carrying a deleterious variant as determined by in vitro protein expression studies. Greater intronic variation unique to ST cases (n =?169) compared with controls (n =?84) was observed with predictions revealing 13 allele candidates that may lead to a potential disruption of splicing and a loss-of-function effect of CYP2C19 in ST cases.

Conclusion

NGS detected CYP2C19 poor metabolizers and paradoxically greater number of so-called rapid metabolizers in ST cases. Rare deleterious exonic variation occurs in 4%, and potentially disruptive intronic alleles occur in 16% of ST cases. Additional studies are required to evaluate the role of these variants in platelet aggregation and clopidogrel metabolism.

  相似文献   
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OBJECTIVES: The primary aim of this study is to determine if patients with end-stage renal disease (ESRD) on peritoneal dialysis (PD) have a higher risk of developing acute pancreatitis (AP) than patients on hemodialysis (HD). The secondary aim is to compare the outcomes of AP between the two groups. METHOD: This is a retrospective case-control study. The study groups consisted of all patients initiated on HD and PD between January 1, 1998 and August 1, 2003. AP was identified using ICD-9 codes. Statistical analysis was carried out using Poisson regression, Kaplan-Meier curve, log-rank test, and Cox regression. RESULTS: One thousand two hundred and thirty-three and 160 eligible patients were identified in the HD and PD groups, respectively. Twenty-eight patients had AP. Eight patients were excluded as they had identifiable etiologies for AP. Of the remaining 20 patients with AP, 14 were in the HD group and 6 were in the PD group (p= 0.009). Incidence of AP was 18.4 per 1,000 person-years in the PD group and 6.5 per 1,000 person-years in the HD group (p= 0.033). Kaplan-Meier curves showed a significant difference in AP-free survival between the two groups (log-rank p= 0.026). Using time-dependent analysis, the hazard ratio for AP in PD patients after adjustment for age and sex was 3.94 (p= 0.006). There was no observed difference in length of hospital stay and ICU stay. All cases of AP were interstitial. There were no complications or deaths related to AP. CONCLUSION: PD is a risk factor for AP. There is no statistical difference in AP-related mortality and morbidity between HD and PD.  相似文献   
77.

Background

Experience with zinc in treating symptomatic hepatic Wilson’s disease (WD) is limited.

Aim

To study the efficacy of Penicillamine followed by zinc in treating symptomatic hepatic Wilson’s disease.

Methods

We retrospectively analyzed case records of 31 symptomatic hepatic WD patients for whom disease severity scores (Child’s, model for end-stage liver disease (MELD), Nazer’s, and New Wilson Index (NWI) score) and 24-h urinary copper were compared at 3-time points—baseline at presentation, at transition from penicillamine to zinc and at end of follow up.

Results

Thirty-one patients (median age 11 [5–24] years) with symptomatic hepatic WD were studied; ten had associated neuropsychiatric manifestations of WD. Penicillamine was changed to zinc sulfate either due to financial constraints (28 patients) or due to adverse effects of penicillamine (3 patients). At presentation (baseline), six patients belonged to Child’s class A, five to Child’s B, and 17 to Child’s C. Duration of initial penicillamine chelation therapy was 134 (2–320) weeks, and of subsequent zinc therapy was 363 (35–728) weeks. There was a significant improvement in liver function tests and disease severity scores (Child’s, MELD, Nazer’s, and NWI score) at the transition from penicillamine to zinc compared to baseline. This improvement was maintained until the end of study period with 90% survival at 10 (2–20) years. Fifteen of the 17 Child’s C cirrhotic patients showed significant improvement in disease severity scores from baseline until end of follow up.

Conclusions

Penicillamine followed by zinc may be a safe and effective treatment in resource-constrained setting for symptomatic hepatic WD patients in all grades of baseline disease severity. Some patients with decompensated cirrhosis due to WD may be managed with medical treatment, avoiding liver transplantation.
  相似文献   
78.
This report describes a simple angiographic viewing rule for coronary angiography in patients of dextrocardia with obstructive coronary artery disease, which could correct the unfamiliar angulated pictures of the coronary tree in dextrocardia into the familiar conventional angiographic pictures of a normally located heart and its associated ease of interpretation.  相似文献   
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