Illegal synthetic dyes in spices: a Singapore case study

Some synthetic dyes are fraudulently added into spices to appeal visually to consumers. Food regulations in several countries, including the United States, Australia, Japan and the European Union, strictly prohibit the use of unauthorised synthetic dyes in food. Nevertheless, illegal practices persist, where spices contaminated with potentially carcinogenic dyes have been documented, posing potential health risks to consumers. In the present study, 14 synthetic dyes were investigated through liquid chromatography/tandem mass spectrometry in 252 commercially available spices in the Singapore market. In 18 out of these (7.1%) at least 1 illegal dye was detected at concentrations ranging from 0.010 to 114 mg/kg. Besides potential health risks, presence of these adulterants also reflects the economic motivations behind their fraudulent use. Findings in the present study further emphasise the need for increased public awareness, stricter enforcement, and continuous monitoring of illegal synthetic dyes in spices to ensure Singapore's food safety.

Determination of ethoxyquin by ultra-high performance liquid chromatography with tandem mass spectrometry and a Singapore survey of ethoxyquin residues in eggs, egg products and poultry

In this study, an advanced ultra-high performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was developed for quantifying ethoxyquin (EQ). The approach employed a distinctive antioxidant added extraction step designed to prevent ethoxyquin decomposition and maintain analytical precision. This method effectively determines residue levels of EQ in eggs, processed egg products, poultry muscle, salmon, and liquid milk. The method was shown to have a limit of quantitation (LOQ) for eggs, milk, salmon, and chicken muscle of 1.5 µg/kg, 1.9 µg/kg, 2.1 µg/kg, and 1.2 µg/kg, respectively. The recoveries of EQ ranged from 79.2% to 107.6%, with a relative standard deviation (RSD) below 8.4%. A surveillance study for the presence of EQ in different types of eggs and poultry muscle available in Singapore was conducted and a total of 140 samples were tested. EQ residues in all samples were found to be below the U.S. Food and Drug Administration (FDA) MRLs of 500 µg/kg. Some samples of salted and preserved eggs from China were detected with higher concentration of EQ.

Determination and Characterization of Gold Nanoparticles in Liquor Using Asymmetric Flow Field-Flow Fractionation Hyphenated with Inductively Coupled Plasma Mass Spectrometry

The EU has approved the usage of gold as a food additive (E175) and it has been applied in numerous foods for coloring and decoration purposes. Different from the general assumption that edible gold is mainly present in the form of flakes or external coating in foods, this work demonstrated that gold nanoparticles (Au NPs) can be released from gold flakes and extracted under optimized conditions. To support future risk assessment associated with the exposure of Au NPs to human health, an effective approach was established in this study for both size characterization and mass determination of Au NPs released in a commercial gold-containing liquor using Asymmetric Flow Field-flow Fractionation (AF4) hyphenated with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Our results showed that no Au NPs were detected in the original liquor product and only after ultrasonication for several minutes did Au NPs occur in the ultrasound-treated liquor. Particularly, Au NPs released in the liquor can be well extracted after 100-fold enrichment of gold flakes and the subsequent ultrasonication for 25 min. Size characterization of Au NPs was conducted by AF4-ICP-MS under calibration with Au NP standards. The gold particle sizes detected ranged from 8.3-398.0 nm and the dominant size of the released Au NPs was around 123.7 nm in the processed liquor. The mass concentration of gold particles determined in the liquor sample with gold flakes concentrated and subsequently sonicated was 48.1 μg L-1 by pre-channel calibration and the overall detection recoveries ranged over 82-95%. For the comparison control samples without ultrasonication, there was no detection of Au NPs. The established method was demonstrated to be useful for monitoring Au NPs in liquor and is possibly applied to other similar foodstuffs.

The detection, characterization, and quantification of dominant degradation products of nisin A and Z in selected dairy products by liquid chromatography-high-resolution mass spectrometry technique

Nisin, a bacteriocin produced through fermentation using bacterium Lactococcus lactis, has several commercial variants such as nisin A and nisin Z. Nisin serves as a natural preservative with antimicrobial properties in various food products, including dairy and beverages, for extending product shelf life. The efficacy and safety of nisin A as a bacteriocin has been well characterized. However, there is limited evidence regarding the efficacy, stability, and safety of nisin Z as a food preservative, as it has not undergone comprehensive regulatory reviews. In this work, we studied the stability of nisin A and Z in a selection of yogurt drinks and found nisin to be unstable, particularly in fruit-flavored yogurt drinks. Both nisin A and Z could experience significant degradation leading to the nisin parent ion peaks dropping below detectable level before the product's expiry date. Compared with nisin A, the formation of oxidized metabolite nisin Z+O appeared to be the predominant reaction for nisin Z. These findings highlight the need for further scientific research to understand the behavior of nisin Z under different application conditions, which is crucial for assessing the efficacy and safety of nisin Z under these conditions. One potential application of this knowledge is to optimize the formulation of yogurt-based drinks to stabilize nisin Z and sustain its biopreservative function throughout the product's shelf life. Additionally, the current study shows that for the testing of the presence of nisin A or nisin Z, it is imperative to cover both the parent and the main degradant(s) of nisin. This is especially true for nisin Z, for which the regulatory approval status may vary in different markets. As such, the confirmative identification of nisin Z and its key metabolites in commercial products would be essential.

Separation and size characterization of highly polydisperse titanium dioxide nanoparticles (E171) in powdered beverages by using Asymmetric Flow Field-Flow Fractionation hyphenated with Multi-Angle Light Scattering and Inductively Coupled Plasma Mass Spectrometry

The application of titanium dioxide as E171 food additive has become an issue of debate due to numerous reports that titanium dioxide nanoparticles (TiO₂ NPs) inside the products may pose risks to human health. However, there is still a lack of an official standardized methodology for the detection and size characterization of TiO₂ particles in foods containing E171. In this study, a method was presented for size characterization of TiO₂ particles with various independent verifications in coffee creamer and instant drink powders, using Asymmetric Flow Field-Flow Fractionation hyphenated with Multi-Angle Light Scattering and Inductively Coupled Plasma Mass Spectrometry (AF4-MALS-ICP-MS). TiO₂ particles from these products were well extracted, followed by their optimized AF4 separation using anionic surfactant Sodium Dodecyl Sulfate (SDS) (0.05%, pH 9) and mixed surfactant NovaChem (0.2%), respectively. Size determination of TiO₂ NPs was conducted based on AF4 calibration with polystyrene nanospheres and verification with TiO₂ NPs standard suspension of 100 nm under two different AF4 conditions. The TiO₂ particle sizes detected ranged from 24.4 - 544.3 nm for coffee creamer and 27.7 - 574.3 nm for instant drink powders, with the TiO₂ NPs detection recoveries of 75% and 92%, respectively. Hydrodynamic diameters from AF4 size calibration could be independently validated by the gyration diameters from online MALS measurement. The established approach was demonstrated to be reliable and pragmatic for size profiling of highly polydisperse TiO₂ particles and thus useful for monitoring E171 in similar foodstuffs.

An effective approach for size characterization and mass quantification of silica nanoparticles in coffee creamer by AF4-ICP-MS

Silicon dioxide (SiO₂) has been used as a food additive (E551) for decades. However, some safety concerns have been raised recently due to the detection of silica nanoparticles (SiO₂ NPs) in a variety of foodstuffs and their unknown long-term health risk to humans. In order for risk assessment to be conducted, it is essential to establish a reliable, valid, and pragmatic method for analysis of SiO₂ NPs in foods for estimation of exposure. This paper presents an effective approach for both size characterization and mass quantification of SiO₂ NPs in commercial high-fat coffee creamer using asymmetric flow field-flow fractionation (AF4) coupled to inductively coupled plasma mass spectrometry (ICP-MS). SiO₂ NPs from coffee creamer were well extracted after cleanup with hexane in a two-phase (hexane vs. water) aqueous environment. Size determination of SiO₂ NPs was performed by on-line AF4-ICP-MS based on calibration with monodispersed standards. The dominant primary size of SiO₂ NPs in the studied sample was 36.5 nm. The mass percentages of SiO₂ NPs (vs. total SiO₂) were 18.6% for the dominant primary nano-silica particles by prechannel calibration and 35.7% for total SiO₂ NPs (≤ 100 nm) by postchannel calibration, with recoveries of 89-96% for the former and 75% for the latter. The established approach was demonstrated to be efficient and practical for routine analysis of polydispersed SiO₂ NPs with wide nano-size distribution in coffee creamer. This method may be extended to monitor the presence of SiO₂ NPs in other similar complex food matrices. Graphical abstract.

Interventions for hidradenitis suppurativa: a Cochrane systematic review incorporating GRADE assessment of evidence quality

More than 50 interventions have been used to treat hidradenitis suppurativa (HS), and so therapy decisions can be challenging. Our objective was to summarize and appraise randomized controlled trial (RCT) evidence for HS interventions in adults. Searches were conducted in Medline, Embase, CENTRAL, LILACS, five trials registers and abstracts from eight dermatology conferences until 13 August 2015. Two review authors independently assessed study eligibility, extracted data and assessed methodological quality. Primary outcomes were quality of life and adverse effects of the interventions. Twelve trials, from 1983 to 2015, investigating 15 different interventions met our inclusion criteria. The median trial duration was 16 weeks and the median number of participants was 27. Adalimumab 40 mg weekly improved the Dermatology Life Quality Index (DLQI) by 4·0 points, which equates to the minimal clinically important difference for the scale, compared with placebo (95% confidence interval -6·5 to -1·5 points). Evidence quality was reduced to 'moderate' because the results are based on only a single study. Adalimumab 40 mg every other week was ineffective in a meta-analysis of two studies comprising 124 participants. Infliximab 5 mg kg(-1) improved the DLQI score by 8·4 points after 8 weeks in a moderate-quality study completed by 33 of 38 participants. Etanercept 50 mg twice weekly was ineffective. Inclusion of a gentamicin sponge prior to primary closure did not improve outcomes. Other interventions, including topical and oral antibiotics, were investigated by relatively small studies, preventing treatment recommendations due to imprecision. More, larger RCTs are required to investigate most HS interventions, particularly oral treatments and surgical therapy. Moderate-quality evidence suggests that adalimumab given weekly and infliximab are effective, whereas adalimumab every other week is ineffective.

Factors associated with pruritic papular eruption of human immunodeficiency virus infection in the antiretroviral therapy era

BACKGROUND

Pruritic papular eruption (PPE) of HIV is common in HIV-infected populations living in the tropics. Its aetiology has been attributed to insect bite reactions and it is reported to improve with antiretroviral therapy (ART). Its presence after at least 6 months of ART has been proposed as one of several markers of treatment failure.

OBJECTIVES

To determine factors associated with PPE in HIV-infected persons receiving ART.

METHODS

A case-control study nested within a 500-person cohort from a teaching hospital in Mbarara, Uganda. Forty-five cases and 90 controls were enrolled. Cases had received ART for ≥ 15 months and had an itchy papular rash for at least 1 month with microscopic correlation by skin biopsy. Each case was individually matched with two controls for age, sex and ART duration.

RESULTS

Twenty-five of 45 cases (56%) had microscopic findings consistent with PPE. At skin examination and biopsy (study enrolment), a similar proportion of PPE cases and matched controls had plasma HIV RNA < 400 copies mL(-1) (96% vs. 85%, P = 0·31). The odds of having PPE increased fourfold with every log increase in viral load at ART initiation (P = 0·02) but not at study enrolment. CD4 counts at ART initiation and study enrolment, and CD4 gains and CD8(+) T-cell activation measured 6 and 12 months after ART commencement were not associated with PPE. Study participants who reported daily insect bites had greater odds of being cases [odds ratio (OR) 8·3, P < 0·001] or PPE cases (OR 8·6, P = 0·01).

CONCLUSIONS

Pruritic papular eruption in HIV-infected persons receiving ART for ≥ 15 months was associated with greater HIV viraemia at ART commencement, independent of CD4 count. Skin biopsies are important to distinguish between PPE and other itchy papular eruptions.

Management of breast cancer with nanoparticle albumin-bound (nab)-paclitaxel combination regimens: a clinical review

BACKGROUND

Monotherapy with nanoparticle albumin-bound (nab)-paclitaxel has demonstrated improved efficacy and safety compared with solvent-based paclitaxel and docetaxel.

DESIGN

A comprehensive review of all reported studies of nab-paclitaxel combinations with other agents in all breast cancer settings was undertaken.

RESULTS

Most studies reviewed are small, phase II and non-comparative. Combinations studied included nab-paclitaxel plus trastuzumab and/or bevacizumab (with or without additional cytotoxic agents), gemcitabine, capecitabine, carboplatin, or lapatinib. The majority of metastatic and neoadjuvant studies demonstrated satisfactory efficacy and safety for nab-paclitaxel combinations, although conclusions regarding comparison with solvent-based taxane (SBT) regimens are not possible. The two adjuvant studies confirmed the safety of nab-paclitaxel combinations in this setting.

CONCLUSIONS

Although results of this review indicate that nab-paclitaxel may be an appropriate substitute for SBTs in combination regimens, additional research is required to confirm the place and cost effectiveness of these combinations before nab-paclitaxel could be recommended routinely in all settings.

Intrathecal chemotherapy alone is inadequate central nervous system prophylaxis in patients with intermediate-grade non-Hodgkin's lymphoma

Central nervous system (CNS) relapse of non-Hodgkin's lymphoma (NHL) is usually fatal despite therapy and effective prophylaxis is desirable. Patients at high-risk usually receive intrathecal (i.t.) prophylaxis, although its efficacy is unproven. We therefore analyzed the outcome of all patients with newly diagnosed "intermediate-grade" NHL receiving i.t. prophylaxis from 1991 to 1999. Twenty-six patients were identified and analyzed. All were free of CNS involvement at diagnosis with negative cerebrospinal fluid (CSF) cytology. Disease stage was IE in 7, and IV in 19, with a median of two extranodal sites involved. Serum lactate dehydrogenase was elevated in 65%, and the median International Prognostic Factors Index score was 3 (range 0-5). Anthracycline-based chemotherapy was used in all cases and included high-dose methotrexate +/- ara-C in six patients. The median number of i.t. treatments was 5 (range 1-12) and comprised methotrexate +/- steroid in 15, together with ara-C in 11. The actuarial 3-year CNS-relapse rate was 26 +/- 10%. Six CNS-relapses were observed and involved the spinal cord or brain parenchyma in two cases each, and the leptomeninges in four patients. Treatment-related variables associated with higher CNS-relapse rates (34-50%) were: delay of > or = 14 days from diagnosis to first i.t. injection, < 5 i.t. treatments, delay of i.t. prophylaxis until after attaining CR and systemic treatment lacking high-dose methotrexate +/- ara-C (each P < or = 0.17). I.t. CNS prophylaxis, as used here, was inadequate. Alternative approaches should be pursued.

Deafness from eighth cranial nerve involvement in a patient with large-cell transformation of mycosis fungoides

Central nervous system (CNS) involvement by mycosis fungoides (MF) is rare and is usually seen in advanced stages with lymph node or visceral involvement. We describe a patient with advanced stage MF in large-cell transformation who presented with profound hearing loss after chemotherapy. Despite an initial differential diagnosis of vincristine-related neurotoxicity based on clinical, audiometric, and MRI investigations, CSF examination revealed lymphomatous leptomeningeal involvement. This case illustrates the importance of an awareness of the possibility of CNS involvement by MF and underlines the need for a complete neurologic evaluation including CSF examination in a patient with underlying MF who presents with a new neurological problem.

Magnetic resonance imaging in the diagnostic management of diseases of the knee

Magnetic resonance imaging (MRI) of the knee is fast assuming a major role in evaluating disorders of the knee. The major advantage of MRI is that it is a totally non-invasive procedure with superior soft tissue contrast resolution and multi-planar capabilities. In contrast to arthrography, intra-articular as well as extra-articular structures in the knee can be evaluated by MRI. Indications include studying abnormalities of the menisci, ligament, patella and quadriceps mechanisms, articular cartilage, bone, bursa and other soft tissue. A review of the literature comparing MRI to arthrography and arthroscopy of the knee, especially in relation to meniscal injuries and anterior cruciate ligament tears, shows wide ranges in the accuracy rates of MRI. There are pitfalls in the interpretation of meniscal tears on MRI like normal variants, tears at the free edge and healed or previously repaired tears. Arthrography remains a useful diagnostic modality in some of these settings.

Use of magnetic resonance imaging in the evaluation of nasopharyngeal cancer

Computerised tomographic (CT) scanning is an established modality in the diagnosis and evaluation of tumours of the nasopharynx. Magnetic resonance (MR) imaging is a newer tool which has rapidly gained acceptance in the same regard due to its innate ability to better characterise and detail soft tissue structures, and its multiplanar scanning ability. This study reviews our experience, in a series of 30 cases, with the use of MR imaging in lesions of the nasopharynx, in particular nasopharyngeal carcinoma. Most of our patients showed involvement of the pharyngeal mucosal and parapharyngeal spaces, as expected. A large number also had intracranial extension. Our sample was probably biased as patients with neurological involvement are more likely to be assessed by MR than CT. Soft tissue infiltration, particularly intracranial extension, was very clearly delineated, especially when intravenous contrast (gadolinium DTPA) was administered. Bone erosion was not well demonstrated. In current clinical practice where radiotherapy is the most common form of treatment for nasopharyngeal carcinoma however, there does not in general, appear to be any clear advantage of MR over CT in the imaging of this particular disease, although there are some exceptions.

Magnetic resonance imaging of leptomeningeal metastases to the spine

Neurologic complications of malignancy can result from paraneoplastic manifestations, cerebral metastases or leptomeningeal involvement. Radiologic evaluation by computerised tomography (CT) has proven to be an invaluable tool in cancer patients with neurologic symptoms. Myelography and CT myelography have been the main modalities for evaluating leptomeningeal metastases. The advent of magnetic resonance imaging (MRI) with contrast has provided an alternative modality for evaluation of leptomeningeal disease. MRI as compared to CT myelography is non-invasive and at least as sensitive. The findings in two patients with leptomeningeal involvement are reported to illustrate the value of MRI.