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Research progress of follicular cytotoxic T cells in HIV infection

Abstract

Recently, a new type of CD8+ T-cell subset, namely, the chemokine (C-X-C motif) receptor 5 (CXCR5+) cluster of differentiation (CD8+) T-cell subset (also called the follicular cytotoxic T-cell (TFC) subgroup), has been discovered around B-cell follicles. The discovery has aroused widespread interest. However, the processes and mechanisms of TFCs taking part in the immune response of the germinal center and their specific roles must still be clearly identified. This article reviews domestic and foreign studies on factors regulating the phenotype, physiological functions, maturity, and differentiation of TFCs and roles and clinical significance of these cells in HIV infection. This review has shown good application prospects for TFCs. The author believes that further studies on TFCs can provide another tool for cytotherapy to control or cure chronic viral infections or tumors.

Open access
Biomarkers of injury to neural tissue in veterinary medicine

Abstract

There are numerous biomarkers of central and peripheral nervous system damage described in human and veterinary medicine. Many of these are already used as tools in the diagnosis of human neurological disorders, and many are investigated in regard to their use in small and large animal veterinary medicine. The following review presents the current knowledge about the application of cell-type (glial fibrillary acidic protein, neurofilament subunit NF-H, myelin basic protein) and central nervous system specific proteins (S100B, neuron specific enolase, tau protein, alpha II spectrin, ubiquitin carboxy-terminal hydrolase L1, creatine kinase BB) present in the cerebrospinal fluid and/or serum of animals in the diagnosis of central or peripheral nervous system damage in veterinary medicine.

Open access
Monitoring of Physiological Changes of Uric Acid Concentration in the Blood of Snakes

Abstract

The evaluation of uric acid concentrations in the blood of snakes is a crucial tool in the diagnosis of gout and renal disease; both prevalent diseases in captive reptiles. However, without an understanding of the physiological fluctuations in uric acid levels and the absence of distinction that makes pathological changes, biochemical parameters are devalued. This study focuses on investigating the relationship between feeding rate and plasma-uric acid concentrations of snakes. The aim of this investigation is to facilitate a better understanding of the feed-induced changes that occur, and to render the analysis of this biochemical parameter as a more potent diagnostic tool. A total of 10 snakes were used in the study and the basal concentration of uric acid was established prior to feeding via blood biochemical analysis. The snakes were then fed rats and successive postprandial blood samples were taken for the monitoring of uric acid levels. The results demonstrated that feeding led to substantial elevations in the uric acid values, whereby postprandial concentrations were significantly elevated for up to 5 days after feeding. The postprandial elevations in uric acid documented in these snakes were of similar levels reported in snakes afflicted with gout or renal disease. The results demonstrated the significant changes that occur to uric acid levels after feeding, and highlights the resemblance between postprandial increases in uric acid and concentrations reported in snakes suffering from renal disease or gout. To avoid a misdiagnosis and to distinguish transient postprandial hyperuricemia from pathological elevations, collecting sufficient anamnestic data on time since last feeding in performing repeated sampling after one week period of fasting is suggested.

Open access
Relationship between Canine Lymphocyte AgNOR Counts and Haematological Indices of Health

Abstract

A modified agyrophil technique was applied to peripheral blood smears to determine the mean AgNOR counts (MAC) of lymphocytes and ultimately assess the state of the lymphoid system in various clinical conditions of dogs. Fifty dogs, from clinically normal to pets with leukaemia, presented to the Veterinary Teaching Hospital, were recruited. Blood smears from each dog were stained with routine Romanowsky and modified agyrophil stains. Signalment, clinical diagnoses and hematologic parameters of the dogs were related to the MAC. An AgNOR proliferative index (AgPI) — percentage of lymphocytes with 3 or more AgNORs, was determined, and correlated with MAC. The statistical significance was determined at P < 0.05. MAC ranged from 1.17 in clinically healthy patients to 6.00 in leukaemic patients. The MAC was 2.00 in patients (n = 26) with lymphocyte counts within reference intervals (900—2400 per microliter); 2.23 in patients (n = 4) with lymphopenia; 2.18 in patients with lymphocytosis (n = 18) and 4.73 in patients (n = 4) with lymphocytic leukemia. Also, the MAC was 2.00 in non-anemic dogs while it was 2.47, 2.49 and 3.06 in patients with mild, moderate and severe anaemia, respectively. The MAC correlated strongly with AgPI (r = 0.91). The ancillary AgNOR technique provides a cheaper, more rapid and sensitive tool than routine lymphocyte counts in assessing the state of lymphoid proliferation in a variety of conditions in the dog.

Open access
Real-time loop-mediated isothermal amplification (LAMP) of mgc2 gene of Mycoplasma gallisepticum

Abstract

Introduction: Mycoplasma gallisepticum is considered the most pathogenic and economically significant avian Mycoplasma spp. for the worldwide poultry industry. The aim of this study was to develop a novel and sensitive real-time loop-mediated isothermal amplification (LAMP) assay based on the amplification of its mgc2 gene sequence for its rapid molecular detection in poultry.

Material and Methods: Blood samples from 300 broiler and layer chickens were screened using a rapid serum agglutination (RSA) test. A real-time LAMP reaction was conducted with seropositive swab samples at 60°C for 90 min in an ESEQuant tube scanner using 6-carboxyfluorescein as the reporting dye.

Results: The sensitivity of the developed assay was 10 fg/μL of DNA. The assay was found 100% specific, showing no cross-reactivity with other avian Mycoplasma species. The proportion found of the positive samples by the real-time LAMP was 58%. In comparison, the RSA was found to detect 52% of positive cases.

Conclusion: The mgc2 real-time LAMP emerged as a more sensitive and accurate method for molecular detection of M. gallisepticum than RSA. Robustness and precision give it applicability as a potential field diagnostic tool for M. gallisepticum control. The study will be beneficial in reducing economic losses that M. gallisepticum inflicts on the poultry industry. This is the first reported development of a real-time LAMP assay based on the amplification of the mgc2 gene sequence using an ESEQuant tube scanner for galline M. gallisepticum detection.

Open access
Analysis of Hair Coat of Dachshund of Longhaired, Shorthaired, and Wirehaired Variety

Abstract

The aim of the study was to analyse the hair coat of the three dachshund varieties, i.e. shorthaired, longhaired, and wirehaired, with respect to its histological structure and content of selected chemical elements. The study was conducted on female dachshunds originating from individual breeders. The study included the assessment of the contribution of particular hair fractions, measurements of hair thickness and length, and also the analysis of histological structure of particular hair fractions. A great differentiation in the parameters and structure of particular kinds of hair from the examined dogs was demonstrated. Thickness and length of hair of particular varieties showed statistically significant differentiation, as well as percentage contribution of particular hair fractions. As regard the content of chemical elements in particular hair fractions and dachshund variety, it appeared that the elements forming hair keratin were the most abundant. The findings presented in the paper may be a useful tool for the recognition of dachshund varieties based on their hair coat structure. They may be also a valuable contribution to the expanding breed standards, which lack histological hair description.

Open access
Phenotypic and genotypic evaluation of adherence and biofilm development in Candida albicans respiratory tract isolates from hospitalized patients

Abstract

In recent years, a significant number of epidemiological variations have been observed for fungal infections. In immunocompromised patients, Candida albicans is crucially involved in invasive infections, mostly originating in respiratory tract colonization. The global rise in candidiasis has led researchers to investigate possible correlations between fungal strains virulence profiles and their pathogenic potential, among the most investigated genes being those involved in adherence and biofilm development. In this study, we established the adherence gene profiles of C. albicans strains isolated from respiratory tract secretions in patients hospitalized for cardiovascular diseases and correlated them with the ability of the respective strains to colonize the epithelial cells and form biofilms on the inert substratum. The strains isolated from the lower respiratory tract exhibited the highest adherence capacity and were intensive biofilm producers. The SAP9, ALS3, ALS5, and ALS6 genes were the most frequently detected. There was a significant association between the presence of ALS 3 gene and the cellular substrate colonizing potential of the harboring strains. We also found that the strains expressing SAP9 were more virulent in the phenotypic assays. Detecting the presence of adherence genes from different clinical isolates is a cost-effective tool that would allow researchers to predict the virulence of a certain strain and estimate its potential to adhere to host cells and develop biofilms.

Open access
Influence of post-mortem muscle glycogen content on the quality of beef during aging

Abstract

Introduction: Glycolic changes which occur post-mortem have an impact on the physical and sensory features of beef, which in turn determine the successive processes and influence such beef quality traits as colour, tenderness, and cooling loss. The aim of this study was evaluation of the post-mortem changes in bovine meat during aging, quantitative analysis of glycogen and lactic acid, as well as examination of their impact on technological and sensory quality of selected muscles from Holstein-Friesian × Limousin breed carcasses.

Material and Methods: The study included three muscles of different metabolic qualities and sarcomere length: m. semitendinosus, m. longissimus dorsi, and m. psoas major, collected from nine bull carcasses aged 24 ±2 months.

Results: Significant correlations were found between the volume of cooling loss on individual days of aging and the pH value of muscle tissue, lactic acid and glycogen content, as well as beef lightness. However, no significant dependency between the volume of glycogen and the intensity of red and yellow colours was detected.

Conclusion: The colorimetric analysis of glycogen and lactic acid can be an effective tool in predicting the quality of beef.

Open access
Identification of HIV-1 Genotypic Resistance in Patients on First-line Antiretroviral Therapy Using Polymerase Chain Reaction and Sequencing

Abstract

Objective The aim of the study was to evaluate the characteristics of HIV drug-genotypic resistance among patients taking first-line ARV regimens using polymerase chain reaction and sequencing, and guide to design optimal ARV regimens for these patients.

Methods HIV reverse transcriptase-encoded gene was amplified with RT-PCR and amplified PCR products were aligned and comparatively analyzed with HIV resistance database to find drug-resistance mutations.

Results Twenty-eight PCR products were amplified and sequenced successfully in 30 serum samples of recruited HIV-infected patients with virologic failure. The resistance rate was 96%, mutations in NRT region were found in 26 patients (93%), while mutations in NNRT region were found in 27 patients (96%). M184V was the most common mutation (86%), K65R was selected in 14% of recruited individuals and TAMs occurred in 50% of patients, which resulted in resistance to NRTIs. Y181C and V179D were the most common mutations in NNRTIs and prevalence was 43% (12/28) and 36% (10/28), respectively, which resulted in cross-resistance to NNRTIs due to low-genetic barrier.

Conclusions Virologic failure may occur in long-term administration of first-line ARV regimens, and drugresistance mutations can be found in these patients, which resulted in resistance to first-line ARV regimens. We emphasized that HIV viral load assay and resistance assay were important tools to guide healthcare workers to design an optimal second-line ARV regimens for HAART-experienced individuals with virologic failure.

Open access
OvSynch protocol and its modifications in the reproduction management of dairy cattle herds – an update

Abstract

Current knowledge about the function of the reproductive tract and appropriate use of hormonal drugs affords control of the oestrus cycle of cows. One of the hormonal protocols is OvSynch, which enables artificial insemination (AI) to be performed at the precise optimum time without control of the ovaries and uterus. Use of such protocols in reproductive management allows oestrus cycles to be synchronised and cows to be effectively inseminated without oestrous detection, which is time-consuming and difficult in farms with numerous cows. Therefore, OvSynch has become the first management tool for AI and is an alternative method to heat detection. Over the 20 years since its first implementation, OvSynch has been modified many times to improve its reproduction outcomes and widen its use. Besides its original use for heat synchronisation, it is also used in many ovarian disorders as a therapeutic method. This review article describes the possibilities which OvSynch provides, its current modifications, various applications, and the advantages and disadvantages of its use in practice.

Open access