43 research outputs found
A review of bioanalytical techniques for evaluation of cannabis (Marijuana, weed, Hashish) in human hair
Cannabis products (marijuana, weed, hashish) are among the most widely abused psychoactive drugs in the world, due to their euphorigenic and anxiolytic properties. Recently, hair analysis is of great interest in analytical, clinical, and forensic sciences due to its non-invasiveness, negligible risk of infection and tampering, facile storage, and a wider window of detection. Hair analysis is now widely accepted as evidence in courts around the world. Hair analysis is very feasible to complement saliva, blood tests, and urinalysis. In this review, we have focused on state of the art in hair analysis of cannabis with particular attention to hair sample preparation for cannabis analysis involving pulverization, extraction and screening techniques followed by confirmatory tests (e.g., GC–MS and LC–MS/MS). We have reviewed the literature for the past 10 years’ period with special emphasis on cannabis quantification using mass spectrometry. The pros and cons of all the published methods have also been discussed along with the prospective future of cannabis analysis
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Prevalence, years lived with disability, and trends in anaemia burden by severity and cause, 1990-2021: findings from the Global Burden of Disease Study 2021
Background
Anaemia is a major health problem worldwide. Global estimates of anaemia burden are crucial for developing appropriate interventions to meet current international targets for disease mitigation. We describe the prevalence, years lived with disability, and trends of anaemia and its underlying causes in 204 countries and territories.
Methods
We estimated population-level distributions of haemoglobin concentration by age and sex for each location from 1990 to 2021. We then calculated anaemia burden by severity and associated years lived with disability (YLDs). With data on prevalence of the causes of anaemia and associated cause-specific shifts in haemoglobin concentrations, we modelled the proportion of anaemia attributed to 37 underlying causes for all locations, years, and demographics in the Global Burden of Disease Study 2021.
Findings
In 2021, the global prevalence of anaemia across all ages was 24·3% (95% uncertainty interval [UI] 23·9–24·7), corresponding to 1·92 billion (1·89–1·95) prevalent cases, compared with a prevalence of 28·2% (27·8–28·5) and 1·50 billion (1·48–1·52) prevalent cases in 1990. Large variations were observed in anaemia burden by age, sex, and geography, with children younger than 5 years, women, and countries in sub-Saharan Africa and south Asia being particularly affected. Anaemia caused 52·0 million (35·1–75·1) YLDs in 2021, and the YLD rate due to anaemia declined with increasing Socio-demographic Index. The most common causes of anaemia YLDs in 2021 were dietary iron deficiency (cause-specific anaemia YLD rate per 100 000 population: 422·4 [95% UI 286·1–612·9]), haemoglobinopathies and haemolytic anaemias (89·0 [58·2–123·7]), and other neglected tropical diseases (36·3 [24·4–52·8]), collectively accounting for 84·7% (84·1–85·2) of anaemia YLDs.
Interpretation
Anaemia remains a substantial global health challenge, with persistent disparities according to age, sex, and geography. Estimates of cause-specific anaemia burden can be used to design locally relevant health interventions aimed at improving anaemia management and prevention.
Funding
Bill & Melinda Gates Foundation
Transtubular Transoral Surgery for Excision of a Dystrophic Os Odontoideum: A Case Report
Transoral approach to the cervico-medullary junction is a well-established procedure. However oropharyngeal complications in the form of soft tissue morbidity postoperatively do occur. We report a case of a teenage boy with traumatic quadriparesis secondary to compression of the cervico-medullary junction by an os odontoideum. Decompression was done via transoral approach through a tubular retractor system, hence obviating the need for the splitting or separate retraction of the soft palate and minimised the damage and violation of surrounding soft tissues. His neurological status improved and he was able to ambulate with support on fourth post-operative day with no soft tissue morbidity in the oral cavity. To our knowledge this is the first case reported using this technique. We conclude that adoption of this method would improve the traditional transoral approach and reduce the oropharyngeal complications
Analysis of ketamine and norketamine in hair samples using molecularly imprinted solid-phase extraction (MISPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS)
An anti-ketamine molecularly imprinted polymer (MIP) was synthesized and used as the sorbent in a solid-phase extn. protocol to isolate ketamine and norketamine from human hair exts. prior to LC-MS/MS anal. Under optimized conditions, the MIP was capable of selectively rebinding ketamine, a licensed anesthetic that is widely misused as a recreational drug, with an apparent binding capacity of 0.13 μg ketamine per mg polymer. The limit of detection (LOD) and lower limit of quantification (LLOQ) for both ketamine and norketamine were 0.1 ng/mg hair and 0.2 ng/mg hair, resp., when 10 mg hair were analyzed. The method was linear from 0.1 to 10 ng/mg hair, with correlation coeffs. (R2) of better than 0.99 for both ketamine and norketamine. Recoveries from hair samples spiked with ketamine and norketamine at a concn. of 50 ng/mg were 86% and 88%, resp. The method showed good intra- and interday precisions
An integrated approach for water minimisation in a PVC manufacturing process
This paper presents a water minimisation study carried out for a polyvinyl chloride (PVC) resins manufacturing plant. Due to the complexity of the mixed batch and continuous polymerisation process, an integrated process integration approach, which consists of process synthesis, analysis and optimisation was used for this work. A simulation model was first developed in a batch process simulation software, SuperPro Designer V6.0, based on the operating condition of a PVC manufacturing process. The batch simulation model captured the essential information needed for a water minimisation study, e.g. process duration, water mass flow, etc. Data extracted from the simulation model was later used in the water minimisation study, utilising the widely established process synthesis technique of water pinch analysis. Two water saving scenarios were presented. Scenario 1 reports a fresh water and wastewater reduction of 28.5 and 90.1% respectively, for the maximum water recovery scheme without water storage system. In Scenario 2, higher fresh water and wastewater reduction are reported at 31.7 and 100% respectively, when water storage tank is installed in the water network