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European Journal of Microbiology and Immunology
Authors:
Kirsten Alexandra Eberhardt
,
Luzia Veletzky
,
Felix Weinreich
,
Richard Odame Phillips
,
Fred Stephen Sarfo
,
Torsten Feldt
,
Albert Dompreh
,
Shadrack Osei Asibey
,
Richard Boateng
, and
Hagen Frickmann

Abstract

Background

Mansonellosis is a widely neglected helminth disease which is predominantly observed in tropical regions. This study was conducted to assess potential associations of the prevalence of circulating Mansonella perstans-specific cell-free DNA in human serum and HIV infection in Ghanaian individuals.

Methods

For this purpose, serum samples obtained from Ghanaian HIV-patients (n = 989) and non-HIV-infected Ghanaian control individuals (n = 91) were subjected to real-time PCR targeting the ITS-(internal transcribed spacer-)2 sequence of M. perstans and Mansonella sp. Deux.

Results

Mansonella-specific cell-free DNA was detected in serum samples of only 2 HIV-positive and 0 HIV-negative individuals, making any reliable conclusions on potential associations between HIV and mansonellosis in tropical Ghana unfeasible.

Conclusions

Future epidemiological studies on hypothetical associations between mansonellosis and HIV infections should focus more specifically on high-endemicity settings for both Mansonella spp.-infections and HIV-infections, include higher case numbers and be based on real-time PCR from whole blood rather than from serum, in which only circulating parasite DNA but no more cell-bound parasite DNA can be detected. However, the study did not show associations of HIV infections in Ghanaian individuals with Mansonella worm loads high enough to detect cell-free Mansonella DNA in serum by PCR.

Open access
European Journal of Microbiology and Immunology
Authors:
Bianca Kelly Neves Izidro da Silva
,
Ana Cláudia Alves Cortez
,
Luciana Aires Oliveira
,
Juan Diego Ribeiro de Almeida
,
Érica Simplício de Souza
,
Katia Santana Cruz
,
Ani Beatriz Jackisch Matsuura
,
Mauricio Morishi Ogusku
,
Karolina Jeaneth Solórzano Chavarría
,
Djane Baía-da-Silva
,
Quique Bassat
,
Marcus Vinícius Guimarães Lacerda
,
Hagen Frickmann
, and
João Vicente Braga de Souza

Abstract

Background

This study aimed at improving a real-time polymerase-chain-reaction (qPCR) assay for the detection of Histoplasma capsulatum, a fungal pathogen that can cause severe respiratory infections in humans, in clinical and soil samples.

Methods

Primer and probes were in-silico designed, in-silico and in-vitro evaluated including clinical biopsy materials and finally subjected to a real-world application with collected soil samples.

Results

Applying the qPCR assay with liver and lung biopsies from 71 patients each, including 59 patients infected with human immunodeficiency virus (HIV), as well as with Sabouraud (SAB) agar culture as the diagnostic reference standard, diagnostic accuracy of the qPCR assay of 100% (5/5) sensitivity and 96% (63/66) specificity for liver samples and 100% (4/4) sensitivity and 94% (63/67) specificity for the lung samples was recorded. When applying the assay with soil samples from caves near of Presidente Figueiredo city, Amazonas, Brazil, one sample from the Maroaga cave was confirmed as positive.

Conclusions

The improved qPCR assessed in this study was successful in detecting H. capsulatum with high efficiency and accuracy in in-vitro evaluation, including the identification of the target pathogen in both clinical and environmental samples.

Open access

Abstract

In our study, using a combination of eye-tracking parameter analysis and the van Westendorp method, we investigate whether participants pay more attention to products that they perceive as more expensive or to those that they prefer in the ranking process. The experiment involved 50 participants, a questionnaire with ranking and pricing tasks, and an eye-tracking measurement. Three wine varieties (Irsai Olivér, Rosé and Merlot-Shiraz) and three different label alternatives were tested. When comparing the results of the ranking and the pricing tasks, the product that is considered more expensive is not always the one that is most appealing to the participants. If we compare the results from the analysis of the eye-tracking parameters and the pricing, we can say that in all cases the labels that received the most visual attention were those that were priced more expensively by the participants.

Open access
Acta Alimentaria
Authors:
Sz. Luzics
,
Á. Tóth
,
T. Barna
,
E. Szabó
,
I. Nagy
,
B. Horváth
,
I. Nagy
,
Z. Varecza
,
I. Bata-Vidács
, and
J. Kukolya

Abstract

Thermobifida alba is the mesophilic member of the Thermobifida genus, the genome and enzyme sets of which have not been described and published yet. Thermobifida strains are thermotolerant actinomycete, which possess wide sets of cellulose and hemicellulose hydrolysing enzymes. Previously, three endomannanases (Man5ATh, Man5ATc, and Man5AThf) of thermobifidas were cloned and investigated, and hereby the endomannanase of T. alba DSM 43795 is described. All four endomannanases belong to the glycoside hydrolase family 5, their sizes are around 50–55 kDa. Their structure consists of a catalytic domain and a carbohydrate binding module, while there is an interdomain linker region in-between consisting repetitive tetrapeptide motifs (eg.: PPTEPTD-Ta, PTDP-Tc, TEEP-Tf, DPGT-Th). The pH optima of Man5A enzymes from T. alba, Thermobifida halotolerans, Thermobifida cellulosilytica, and Thermobifida fusca are slightly different (6.5, 7.0, 7.5, and 8.0, respectively), however, the temperature optima of the enzymes were detected within a wider range of 65–75 °C. In this research, Man5ATa exhibited the lowest Michaelis-Menten constant (KM) (0.13 mM) on LBG-mannan substrate, while others shared similar kinetic parameters: 0.9–1.7 mM of KM. Despite the high sequence similarity of the investigated mannanases, they exhibit different temperature stability parameters. These different functional characteristics can be advantageous for industrial applications producing biologically active, oligomannan prebiotics under different conditions.

Open access

Abstract

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) characterized by inflammation and neurodegeneration. Current research suggests that diet may influence disease course, severity of symptoms, and quality of life in MS patients. The ketogenic diet (KD) has been used for more than a century as a therapeutic approach for various medical conditions. It was originally developed in the 1920s as a treatment option for epilepsy, and especially in the last 30 years, has gained popularity for its potential benefits in a variety of neurological conditions other than epilepsy. This prompted us to perform a literature survey regarding the effect of KD on the onset and progression of MS. The here reviewed 15 original research articles including in vitro, preclinical, and clinical studies provide evidence for the safety and feasibility of the KD in MS, showing potential neuroprotective effects and positive impacts on cellular metabolism and disease outcome. Since the literature is limited and most studies were conducted with low numbers of MS patients and rather exploratory in nature, further studies with larger cohorts are needed to gain a better understanding of the mechanisms by which the improvements of the MS disease course are achieved.

Open access

Abstract

The prevalence of Campylobacter jejuni infections is increasing worldwide and responsible for significant morbidities and socioeconomic expenses. The rise in antimicrobial resistance of C. jejuni underscores the urge for evaluating antibiotics-independent compounds as therapeutic and preventive treatment options of human campylobacteriosis. Given its well-known anti-microbial and immune-modulatory properties we here surveyed the disease-modifying effects of trans-cinnamaldehyde pretreatment in experimental campylobacteriosis. Therefore, secondary abiotic IL-10−/− mice were orally challenged with trans-cinnamaldehyde starting 7 days prior C. jejuni infection. Whereas gastrointestinal colonization properties of the enteropathogens remained unaffected, trans-cinnamaldehyde pretreatment did not only improve clinical signs in infected mice, but also alleviated colonic epithelial cell apoptosis on day 6 post-infection. Furthermore, trans-cinnamaldehyde application resulted in less pronounced T cell responses in the colon that were accompanied by dampened proinflammatory mediator secretion in distinct intestinal compartments. Notably, the immune-modulatory effects of trans-cinnamaldehyde were not restricted to the intestinal tract but could also be observed in extra-intestinal organs such as the liver and kidneys. In conclusion, our preclinical placebo-controlled intervention study provides first evidence that due to its immune-modulatory effects, trans-cinnamaldehyde constitutes a promising prophylactic option to alleviate campylobacteriosis.

Open access

Abstract

In the study, suitability of porridge, bun, and salad prepared from processed pearl millet FBC16 and sorghum PSC4 had been evaluated organoleptically by a panel of semi-trained judges and 25 non-insulin dependent diabetes mellitus subjects. Organoleptically, germinated pearl millet was found to be more suitable for porridge (50%) and salad (100%), while puffed sorghum was best suitable for bun (15%) preparation. Prepared porridge had significantly (P ≤ 0.05) higher protein (16.9%) and total phenols (178.8 mg GAE/100 g) contents and antioxidant capacity (1,036 mg TE/100 g) than control. The dietary fibre and in vitro starch digestibility of composite porridge and bun increased significantly (P ≤ 0.05). Most acceptable composition of porridge, bun, and salad had low glycaemic index (17.64–26.79) and medium to low glycaemic load (8.82–13.40). Suitability of pearl millet and sorghum using appropriate processing techniques (germination and puffing) is recommended for preparation of indigenous food products especially for diabetics.

Open access

Abstract

This study aimed to investigate the anti-obesity potential of camel colostrum and milk proteins as well as their enzymatic hydrolysates. Camel colostrum and milk proteins were treated using six proteolytic enzymes (pepsin, trypsin, α-chymotrypsin, pancreatin, papain, and pronase). The degree of hydrolysis was measured to verify the degradation of proteins. The in vitro anti-obesity activity was evaluated using the pancreatic lipase inhibitory assay. Camel colostrum and milk protein hydrolysates exhibited different degrees of hydrolysis ranging from 17.69 to 43.97%. The protein content varied between 56.08–61.95% and 37.39–41.72% for camel colostrum and milk protein hydrolysates, respectively. The hydrolysates displayed significantly higher anti-obesity activity than the undigested proteins at all tested concentrations (P < 0.05). Colostrum protein hydrolysate generated with pancreatin had the highest anti-obesity potential (59.92%). These results suggest that colostrum and milk protein hydrolysates could be used to formulate functional foods and nutraceuticals.

Open access

Abstract

The aim of this study was to assess the nutritional quality of homemade beef sausages by examining the amino acid, biogenic amine, and fatty acid composition. The most abundant amino acids were Ala (15.56%), Leu (13.28%), Gly (8.64%), Pro (8.41%), Ser (8.26%), and Val (7.65%). The essential amino acids accounted for 44.30% of total amino acids. Apart from the protein building amino acids, the free amino acid content was relatively high, accounting for 10% of total amino acid content. The average biogenic amine concentration in the sausage samples was low (1.69 mg kg−1). Saturated fatty acids accounted for 59.10% of total fatty acids, followed by monounsaturated (38.63%) and polyunsaturated fatty acids (2.27%). The fatty acid profile was dominated by oleic (C18:1, 34.37%) and palmitic (C16:0, 30.24%) acids, and short-chain fatty acids were also present, which may have a positive impact on gut health. The results show that beef sausages have a high nutritional value and are a good source of essential amino acids, free amino acids, and fatty acids that are important for human health.

Open access

Abstract

Food allergies became a major public health and food safety interest in the past decades as their prevalence is increasing, and their only available treatment is a strict elimination diet that necessitates appropriate food labelling regulations. While such regulations are available worldwide, most of them are not taking into account inadvertent allergen cross-contamination and they usually do not define threshold doses that could support the industry in their endeavour to provide reliable food labels for allergic consumers. This resulted in the proliferation of the “may contain” type precautionary allergen labelling (PAL), which is voluntary and is intended to warn consumers for potential unintended contamination with an otherwise undeclared allergen. As this kind of labelling is hardly ever based on actual risk assessment, it puts both the industry and the consumer into a difficult position. A promising tool towards the solution of this problem could be allergen threshold doses based on clinical data, which are becoming increasingly available. This review intends to present this process, the new ways of improved risk assessment it opens, and its implications for food analysis.

Open access