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Local and systemic influence of toxic levels of airborne ozone on the inflammatory response in rats
2021
Chmielewska-Krzesińska, Małgorzata | Wąsowicz, Krzysztof
Ozone is not harmful itself; however, it directly oxidises biomolecules and produces radical-dependent cytotoxicity. Exposure to ozone is by inhalation and therefore the lungs develop the main anti-inflammatory response, while ozone has an indirect impact on the other organs. This study investigated the local and systemic effects of the ozone-associated inflammatory response. Three groups each of 5 Wistar Han rats aged 6 months were exposed for 2h to airborne ozone at 0.5 ppm and a fourth identical group were unexposed controls. Sacrifice was at 3h after exposure for control rats and one experimental group and at 24 h and 48 h for the others. Lung and liver samples were evaluated for changes in expression of transforming growth factor beta 1, anti-inflammatory interleukin 10, pro-inflammatory tumour necrosis factor alpha and interleukin 1 beta and two nuclear factor kappa-light-chain-enhancer of B cells subunit genes. Total RNA was isolated from the samples in spin columns and cDNA was synthesised in an RT-PCR. Expression levels were compared to those of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and analysed statistically. All variables changed non-linearly over time comparing experimental groups to the control. Conspicuous expression changes in the subunit genes and cytokines were observed in both evaluated organs. Locally and systemically, inflammation responses to ozone inhalation include regulation of certain genes’ expression. The mechanisms are unalike in lungs and liver but ozone exerts a similar effect in both organs. A broader range of variables influential on ozone response should be studied in the future.
اظهر المزيد [+] اقل [-]Clinical use of the parasympathetic tone activity index as a measurement of postoperative analgaesia in dogs undergoing ovariohysterectomy
2021
While the current tools to assess canine postoperative pain using physiological and behavioural parameters are reliable, an objective method such as the parasympathetic tone activity (PTA) index could improve postoperative care. The aim of the study was to determine the utility of the PTA index in assessing postoperative analgaesia. Thirty healthy bitches of different breeds were randomly allocated into three groups for analgaesic treatment: the paracetamol group (GPARAC, n = 10) received 15 mg/kg b.w., the carprofen group (GCARP, n = 10) 4 mg/kg b.w., and the meloxicam group (GMELOX, n = 10) 0.2 mg/kg b.w. for 48 h after surgery. GPARAC was medicated orally every 8 h, while GCARP and GMELOX were medicated intravenously every 24 h. The PTA index was used to measure the analgaesia–nociception balance 1 h before surgery (baseline), and at 1, 2, 4, 6, 8, 12, 16, 20, 24, 36, and 48 h after, at which times evaluation on the University of Melbourne Pain Scale (UMPS) was made. The baseline PTA index was 65 ± 8 for GPARAC, 65 ± 7 for GCARP, and 62 ± 5 for GMELOX. Postoperatively, it was 65 ± 9 for GPARAC, 63 ± 8 for GCARP, and 65 ± 8 for GMELOX. No statistically significant difference existed between baseline values or between values directly after treatments (P = 0.99 and P = 0.97, respectively). The PTA index showed a sensitivity of 40%, specificity of 98.46% and a negative predictive value of 99.07%. Our findings suggest that the PTA index measures comfort and postoperative analgaesia objectively, since it showed a clinical relationship with the UMPS.
اظهر المزيد [+] اقل [-]New insights into the prevalence and phylogenetic diversity of Cysticercus ovis isolates in sheep from Sulaymaniyah, Iraq
2021
Although ovine cysticercosis is not a zoonotic problem, it results in substantial economic losses due to the condemnation of infected tissues or entire carcasses. This study aimed to record preliminary data on the prevalence, and phylogenetic diversity of Cysticercus ovis isolates from slaughtered sheep in the province of Sulaymaniyah, Iraq. From January to September 2020, 6, 411 slaughtered sheep were examined for C. ovis by routine meat inspection. The amplification and sequence analysis of the COX1 gene for up to 35 specimens of C. ovis was performed using conventional PCR. The overall prevalence rate was 1.3%, and the prevalence was significantly higher in older sheep (>1 year) than younger ones (<1 year) (P< 0.05). The cardiac muscle showed a higher tendency to carry C. ovis infection compared to other examined muscles. Sequence analysis of the COX1 gene revealed six haplotypes, and the level of pairwise nucleotide diversity between individual haplotypes was 1–2%. Five out of six of the Taenia ovis haplotypes recovered could have been recorded for the first time globally. Phylogenetic interpretation indicated that all the T. ovis haplotypes clustered in a single clade, and it also indicated an extremely close similarity to Iranian and New Zealand isolates. Globally, this report adds new data on C. ovis genetic diversity, which provide an extremely useful molecular background with regard to future preventive as well as control strategies.
اظهر المزيد [+] اقل [-]Canine leishmaniasis prevalence in the Slovenian dog population
2021
Kotnik, Tina | Moreno Lázaro, Javier | Šoba, Barbara | Krt, Brane | Skvarč, Miha | Vergles Rataj, Aleksandra | Gorišek Bajc, Maja | Ravnik Verbič, Urša
Leishmaniasis is a life-threatening zoonosis of which dogs are the major reservoir and sandflies are the vectors. Until now, the prevalence of canine leishmaniasis (CanL) in the Slovenian dog population was unknown. Epidemiological data, eye swabs and blood samples were taken from 465 dogs born in Slovenia and older than one year. Commercial ELISA kits and real-time PCR were used. For ELISA-positive samples, an immunofluorescence antibody test (IFAT) was performed. Descriptive statistics were used to characterise the samples. The one-sample nonparametric chi-square test was used to test whether the categories of a variable were equally distributed. A 59.9% proportion of the recruited dogs had travelled to endemic regions and 62.1% of them had not been protected by insect repellents. Skin symptoms that might be CanL-related were described in 109 of the dogs’ histories (23.4%), inappetence and/or weight loss in 25 (5.4%), and anaemia, intermittent fever, and/or lymphadenopathy in 19 (4.1%). At the time of recruitment, all dogs were asymptomatic. All samples were PCR negative, nine (1.9%) were ELISA positive, but none were IFAT positive. Five of the nine ELISA-positive dogs were non-travellers. We conclude that the seroprevalence of canine leishmaniasis of 1.9 % in the autochthonous Slovenian dog population may pose a risk of endemic spread of the disease.
اظهر المزيد [+] اقل [-]Modification of a haematoxylin, eosin, and natural saffron staining method for the detection of connective tissue
2021
Ceccopieri, Cassandra | Skonieczna, Joanna | Madej, Jan P.
The aim of our study was to optimise an existing staining procedure: haematoxylin-eosin saffron (HES). The method follows the classical haematoxylin and eosin protocol with the addition of a staining step using natural saffron to better identify the collagen fibres. The saffron solution was obtained by dissolving ground saffron stigmas in absolute alcohol. In order to test the HES method for its staining ability on four main types of collagen (I, II, III, and IV), specific tissues (skin, tooth, cartilage, aorta, spleen, and penis) were chosen. The procedure showed a sharp differentiation between muscle, stained red or pink, and connective tissue, stained bright yellow or orange. HES allows the diagnosis of reticulin fibrosis undetected in HE and in previous saffron staining procedures. HES represents an advantageous alternative to HE staining giving highly reproducible results with high diagnostic value.
اظهر المزيد [+] اقل [-]Expression, purification, and bioactivity of a soluble recombinant ovine interferon-tau in Escherichia coli
2021
Yu, Hai-Yang | Gao, Dong-Mei | Zhou, Wei | Xia, Bing-Bing | He, Zhi-Yuan | Wu, Bo | Jiang, Min-Zhi | Wang, Mingli | Zhao, Jun
Ovine interferon-tau (oIFN-τ) is a newly discovered type I interferon. This study used biochemical techniques to transform the oIFN-τ gene into Escherichia coli to obtain the mass and soluble expression of the recombinant protein. First, total RNA was extracted from fresh sheep embryonic tissues with TRIzol reagent and then used as a template to reverse transcribe and amplify the mature oIFN-τ gene with RT-PCR. The amplified product was next digested with the HindIII and XhoI restriction enzymes and inserted into the pET-32a(+) vector to construct the prokaryotic expression plasmid. The corrected in-frame recombinant plasmid, pET-32a(+)-oIFN-τ, was transformed into E. coli Rosetta (DE3) competent cells. After induction with isopropyl-beta-D-thiogalactopyranoside (IPTG), the recombinant protein was detected in bacteria. Finally, the bacteria were lysed by sonication, and the recombinant protein was purified by nickel affinity chromatography and DEAE anion exchange chromatography. The protein was confirmed to be oIFN-τ, which mainly existed in the soluble lysate fraction, as proven by SDS-PAGE and Western blot assays. Purified IFN-τ exists mostly in a soluble form, and its anti-vesicular stomatitis virus (VSV) activity reached 7.08×10(6)IU/mL.
اظهر المزيد [+] اقل [-]In vivo study of the oestrogenic activity of milk
2021
Radko, Lidia | Posyniak, Andrzej
Milk has been suggested to be a possible source of oestrogenically active compounds. In order to assess the health risk for milk consumers and ensure the safety of this staple part of the human diet, it is important to study the effect of xenooestrogen mixtures present in milk. This investigation used the available in vivo model to learn to what extent such compounds may be endocrine disruptors. The recommended immature golden hamster uterotrophic bioassay was chosen. A total of 132 animals were divided into nine groups of experimental animals and positive and negative control groups, each of 12 animals. The experimental females received ad libitum either one of five samples of raw cow’s milk from individual animals or one of four samples of pasteurised or ultra-high temperature treated cow’s milk as retail products. After 7 days, the animals were sacrificed and necropsied. Uterine weight increases were measured as the endpoint of oestrogenic activity in milk. The milk samples from individual cows and the retail milk samples did not show oestrogenic activity. However, in three groups, decreased uterine weights were observed. Considering that milk supplies are beneficial to health, contamination in this food should be avoided. There is a need for further animal experiments and epidemiological studies are warranted to evaluate any causative role of milk in human endocrinological disorders.
اظهر المزيد [+] اقل [-]Identification of histamine in fish and fish products in Poland during 2014–2018
2021
Pawul-Gruba, Marzena | Osek, Jacek
Histamine is one of the most important and toxic biogenic amines which may be present in food and may cause food poisoning in humans when contained at a high level. It is produced during bacterial decarboxylation of histidine in fish muscles. The aim of the study was to investigate the presence of histamine in fish and fish products available in Poland during 2014–2018. A total of 421 samples of raw (248), smoked (107), canned (50), and marinated fish (16) were analysed by high-performance liquid chromatography with diode array detection. Histamine was detected in 14.1% samples of raw fish, 29% of smoked fish, 22% of canned fish and 93.8% of marinated fish in concentrations ranging from 3.4 to 156.4 mg/kg. Content of this amine above 100 mg/kg was found in four samples: raw Atlantic salmon, smoked European sprat and two samples of marinated Atlantic herring. The study showed that fish and fish products on the Polish market generally meet the food safety criteria for histamine and are safe for consumers.
اظهر المزيد [+] اقل [-]Environmental contamination of free-range hen with dioxin
2021
Mikołajczyk, Szczepan | Pajurek, Marek | Warenik-Bany, Małgorzata | Maszewski, Sebastian
The transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) from a contaminated environment into the food chain is a serious consumer safety problem. As part of the Polish National Surveillance Program of PCDD/Fs and PCBs in food of animal origin, a concentration of PCDD/Fs of 4.61 ± 0.75 pg WHO-TEQ/g fat was determined in a sample of free-range eggs, which exceeded the permitted limit of 2.5 pg WHO-TEQ/g. The aim of the study was to investigate the source of the egg contamination and the risk for the eggs’ consumers. Eggs, muscles, feed and soil from the place where backyard waste burning had been carried out in the past and ash from a household stove tipped onto the paddock were analysed using the isotope dilution technique with high-resolution gas chromatography coupled with high-resolution mass spectrometry. The concentration in ash was low at 0.20 pg WHO-TEQ/g and the congener profile did not indicate the source of contamination. The dioxin content in soil from the backyard waste-burning site was 2.53 pg WHO-TEQ/g dry matter (d.m.) and the soil’s profile of PCDD/F congeners matched the profile of the contaminated eggs. By reason of the congener profile similarity, the investigation concluded, that the cause of the contamination was the backyard waste-burning site soil which the animals had access to. Frequent consumption of contaminated eggs from the analysed farm could pose a health risk due to chronic exposure, especially for vulnerable consumers.
اظهر المزيد [+] اقل [-]The protective action of piperlongumine against mycobacterial pulmonary tuberculosis in its mitigation of inflammation and macrophage infiltration in male BALB/c mice
2021
Lu, Nihong | Yang, Yongrui | Li, Xiaofei | Li, Jie | Cheng, Jie | Lv, Zhengxuan | Du, Yingrong
Piperlongumine (PL) is a bioactive alkaloid and medicinal compound of piperamide isolated from the long pepper (Piper longum Linn). It has demonstrated bactericidal action against Mycobacterium tuberculosis (MTB), the cause of pulmonary tuberculosis; nevertheless, immunomodulatory activity had not been identified for it in MTB-triggered granulomatous inflammation. This study investigated if piperlongumine could inhibit such inflammation. Mycobacterium tuberculosis strain H37Rv was subjected to a broth microdilution assay. Piperlongumine at 5, 15, and 25 μg/mL, 0.2% dimethyl sulphoxide as control or 4 μM of dexamethasone were tested in vitro on MH-S murine alveolar macrophages. BALB/c mice were orally administered PL at 50, 100 and 150 mg/kg b.w. after trehalose-6,6-dimycolate (TDM) stimulation. Chemokine and cytokine concentrations were determined in lung supernatants. Flow cytometry and Western blot analysis were performed to determine phosphorylated spleen tyrosine kinase (Syk), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) pathways. Piperlongumine inhibited inflammatory mediators and adherence of lymphocyte function-associated antigen 1 to MH-S cells following TDM activation. It also improved macrophage clearance of MTB. In TDM-stimulated MH-S cells, PL significantly influenced the macrophage inducible Ca²⁺-dependent lectin receptor (Mincle)-Syk-ERK signalling pathway. Oral dosing of PL effectively suppressed the development of pulmonary granulomas and inflammatory reactions in the TDM-elicited mouse granuloma model. PL as an inhibitor of MTB-triggered granulomatous inflammation may be an effective complementary treatment for mycobacterial infection.
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