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Open access

Quan Liang

Abstract

Hepatitis C virus (HCV) is the main pathogen causing chronic hepatitis and primary liver cancer. Various viral proteins and host cell molecules are involved in the HCV cell entry, but the mechanism of infection has not been completely elucidated. The transferrin receptor can act as a receptor for many viruses during cell entry. The transferrin receptor is not only closely related to HCV-induced iron metabolism disorders but also mediates the fusion of HCV with the host cell membrane as a specific receptor for CD81-dependent viral adhesion.

Open access

Guoxiu Lu

Abstract

Sepsis is a systemic inflammatory response caused by infection and a critical illness in pediatrics. This disease is the leading cause of death in infants and children worldwide. An early, appropriate, and adequate anti-infective treatment can effectively prevent disease progression and improve the survival rate of children. However, antimicrobial drug abuse, increased drug-resistant bacteria, and lack of epidemiological data have hampered the effective and rational anti-infective treatment of patients with sepsis and enhancement of the success rate of rescue, especially for children. This article briefly reviews the recent advances in anti-infective treatment for sepsis in children at home and abroad based on sepsis definition, pathogen distribution and drug resistance, infection source control, and rational anti-infection. The results provide a foundation for clinical treatment of sepsis.

Open access

Li Han

Abstract

The harms of seasonal flu and global pandemic influenza have generally attracted attention. However, the currently administered influenza drugs and flu vaccines have certain limitations. Since the discovery of the small interfering RNA (siRNA) and its mediated RNA interference process, this molecule has been widely used in the study of anti-influenza viral infections because of its high specificity and strong selectivity. The results provided new concepts for the prevention and treatment of influenza virus. However, the siRNA still faces an enormous challenge despite extensive studies on this molecule. The research progress of siRNA in anti-influenza viral infection was reviewed in this study.

Open access

Xiaoming Gu

Abstract

Objective

The objective of this study was to understand the pathological mechanism and therapeutic progress in the study of urinary tract infections to provide references for clinical diagnosis and identification and development of therapeutic drugs.

Methods

We summarized the types, pathological mechanisms, and therapeutic drugs for urinary tract infections on the basis of recent publications on these infections, both domestic and abroad.

Results and conclusions

Urinary tract infection is mainly caused by pathogenic bacterial infection and treated by targeting bacterial adhesion, bacterial toxin, protease, urease, and siderophores, as well as using pili as vaccines and small-molecule drugs. Vaccines that target bacterial adhesion can block well the interaction between pathogens and the body, thereby reducing the incidence of urinary tract infections. The clinical efficacy of vaccines targeting bacterial toxins and proteases needs further evaluation. Vaccines targeting iron carriers retard disease progression and attenuate bacterial colonization. Urease-targeted small-molecule drugs exhibit certain curative effects and serious side effects. Small pili-targeted drugs can prevent and treat urinary tract infections by blocking the colonization and invasion of pathogens in animal models of urinary tract infections on the bladder. Adhesive FimH antibodies have entered Phase I clinical trials. However, pilicides, mannosides, and vaccines that target pili, iron carriers, and other virulence factors are still in the experimental or preclinical stages of research.

Open access

Hua Feng

Abstract

Helicobacter pylori (Hp) is one of the most common human pathogens. The infection caused by this bacterium is closely related to various clinical diseases. However, the eradication rate of conventional quadruple therapy has decreased, but the recurrence rate of infections has increased. The oral cavity is another major storage of Hp in addition to the stomach, and a certain homology exists between Hp in the oral cavity and Hp in the stomach. Periodontal treatment has a certain role in the killing of oral Hp, which can increase the eradication rate and reduce the recurrence rate of Hp in the stomach. This article summarizes the influence of oral Hp on the eradication rate and recurrence rate of gastric Hp.

Open access

Tong Wang

Abstract

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an acute progressive respiratory failure caused by severe infection, trauma, shock, poisoning, inhaled harmful gas, acute pancreatitis, and pathological obstetrics. ALI and ARDS demonstrate similar pathophysiological changes. The severe stage of ALI is defined as ARDS. At present, a significant progress has been achieved in the study of the pathogenesis and pathophysiology of ALI/ARDS. Whether or not ALI/ARDS patients can recover depends on the degree of lung injury, extra-pulmonary organ damage, original primary disease of a patient, and adequacy in supportive care. Conservative infusion strategies and protective lung ventilation reduce ARDS disability and mortality. In this study, the pathogenesis of ALI/ARDS, lung injury, molecular mechanisms of lung repair, and conservative infusion strategies and pulmonary protective ventilation are reviewed comprehensively.

Open access

Ewelina Kowalczyk and Krzysztof Kwiatek

Abstract

Introduction: Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by many plant species. Due to their toxicity PAs can pose a risk to human and animal health. To detect the toxic compounds in feed materials a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed.

Material and Methods: PAs were extracted with sulphuric acid and purified with cation exchange cartridges. A newly developed solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC-MS analysis.

Results: The developed method was validated according to SANTE/11945/2015 guidelines. The recovery was from 84.1% to 112.9%, the repeatability ranged from 3.0% to 13.6%, and the reproducibility was from 4.8% to 18.9%.

Conclusions: A sensitive and selective method for determination of PAs in feed materials has been developed and validated. All evaluated validation parameters were in accordance with EU Reference Laboratories document no. SANTE/11945/2015. Almost 41% of the analysed feed samples were positive for the presence of at least one PA.

Open access

Ewelina Kowalczyk and Krzysztof Kwiatek

Abstract

Introduction: Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed.

Material and Methods: PAs were extracted with 0.05 M sulphuric acid and purified with MCX cartridges. A solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine (8:1:1:0.1:0.1, v/v) was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC–MS analysis.

Results: The developed method was validated according to SANTE/11945/2015 requirements. The recovery was from 80.6% to 114.5%. The repeatability ranged from 2.3% to 14.6%, and the reproducibility was from 4.9% to 17.7%.

Conclusions: A new method for the determination of PAs in honey has been developed and validated. All evaluated parameters were in accordance with the SANTE/11945/2015 guidance document. Out of 50 analysed honey samples, 16 (32%) were positive for the content of at least one PA.

Open access

Alfredo Rosamel Rodriguez, Daniel Eduardo Herzberg, Marianne Patricia Werner, Heine Yacob Müller and Hedie Almagro Bustamante

Abstract

Introduction: Lameness is a painful and debilitating condition that affects dairy cows worldwide. The aim of this study was to determine the plasma concentration of norepinephrine, β-endorphin, and substance P in dairy cows with lameness and different mobility scores (MS).

Material and Methods: A total of 100 Friesian and Jersey cows with lameness (parity range: 1–6; weight: 400–500 kg; milk yield: 22–28 L a day, and lactation stage less than 230 days) were selected. Animals were selected and grouped according to MS (MS 0–3; n = 25), and plasma concentration of norepinephrine, substance P, and β-endorphin was measured using ELISA.

Results: Cows with MS 3 had higher plasma concentrations of norepinephrine and substance P and lower plasma concentrations of β-endorphins when compared to MS 0 cows.

Conclusion: Variations in plasma concentration of norepinephrine, substance P, and β-endorphin could be associated with intense pain states in dairy cows with lameness, but are insufficient to differentiate these states from the mildest pain states. Further studies are necessary in order to evaluate the potential use of these biomarkers in the detection of chronic bovine painful conditions.

Open access

Marta Piątkowska, Michael Sulyok, Katarzyna Pietruszka and Łukasz Panasiuk

Abstract

Introduction: A mini-study of 20 raw milk samples was conducted to examine the spectrum of fungal metabolites in sheep milk from the first spring milking.

Material and Methods: Samples were collected from randomly selected ewes in two animal flocks from the Bieszczady Mountains and analysed using liquid chromatography-tandem mass spectrometry.

Results: Out of ~700 bacterial, fungal, and plant metabolites tested for, only one mycotoxin – Enniatin B – was detected in sheep milk samples (18/20; 0.0055–0.0121 μg/kg; 0.0078 μg/kg average).

Conclusions: The results indicated that there was no high-level exposure to fungal metabolites via consumption of raw sheep milk during the sample collection period.