Mechanistic Understanding of Candida albicans Biofilm Formation and Approaches for Its Inhibition

In recent years, the demand for novel antifungal therapies has increased several- folds due to its potential to treat severe biofilm-associated infections. Biofilms are made by the sessile microorganisms attached to the abiotic or biotic surfaces, enclosed in a matrix of exopolymeric substances. This results in new phenotypic characteristics and intrinsic resistance from both host immune response and antimicrobial drugs. Candida albicans biofilm is a complex association of hyphal cells that are associated with both abiotic and animal tissues. It is an invasive fungal infection and acts as an important virulent factor. The challenges linked with biofilm-associated diseases have urged scientists to uncover the factors responsible for the formation and maturation of biofilm. Several strategies have been developed that could be adopted to eradicate biofilm-associated infections. This article presents an overview of the role of C. albicans biofilm in its pathogenicity, challenges it poses and threats associated with its formation. Further, it discusses strategies that are currently available or under development targeting prostaglandins, quorum-sensing, changing surface properties of biomedical devices, natural scaffolds, and small molecule-based chemical approaches to combat the threat of C. albicans biofilm. This review also highlights the recent developments in finding ways to increase the penetration of drugs into the extracellular matrix of biofilm using different nanomaterials against C. albicans.

Evaluation of Dietary Habits in the Study of Pancreatic Cancer

BACKGROUND

Pancreatic cancer is serious and rapidly progressing condition. Little is known about the role of diet in etiology of pancreatic cancer. The study focused on the role of selected dietary factors related to pancreatic cancer.

MATERIAL AND METHODS

The case-control study was performed in the Czech Republic in 2006- 2009, involving three centers in Olomouc, Ostrava and Ceske Budejovice. It comprised a total of 530 persons, of whom 310 had pancreatic cancer and 220 were controls. Data were obtained directly from each participant in an interview with a trained interviewer and entered into a standardized questionnaire. The data were analyzed using a crude odds ratio (OR) and multivariate logistic regression with an adjusted OR and 95% CI. The statistical analysis was performed with the STATA v. 10 software.

RESULTS

A very strong protective effect was found in pickled cabbage (OR 0.32; 95% CI 0.19- 0.55), broccoli (OR 0.37; 95% CI 0.25- 0.53), cooked onion (OR 0.14; 95% CI 0.08- 0.27), tomatoes (OR 0.28; 95% CI 0.13- 0.60), raw carrot (OR 0.33; 95% CI 0.20- 0.56), cooked carrot (OR 0.35; 95% CI 0.19- 0.62). In logistic regression model, statistically significant protective associations were found in consumption of more than three portions of cooked vegetables per week (OR 0.16; 95% CI 0.05- 0.55) and high consumption of citrus fruit (OR 0.46; 95% CI 0.23- 0.90).

CONCLUSION

The study found statistically significant protective effect of consumption of more than three portions of cooked vegetables per week and high consumption of citrus fruit.

Is physical activity a protective factor against pancreatic cancer?

OBJECTIVES

The objective of the study was to analyze an association between selected factors and pancreatic cancer, assuming that knowing the etiology would help influence the incidence of this severe type of cancer through primary prevention. In addition to age, gender, BMI and education, the analysis aimed at assessing occupational and leisure-time physical activities with respect to pancreatic cancer.

BACKGROUND

In numerous studies, physical activity is reported to be a protective factor against pancreatic cancer.

METHODS

A case-control study was carried out in three centers in the Czech Republic in 2006-2009.

RESULTS

The study comprised a total of 529 individuals, of which 309 were patients with pancreatic cancer and 220 were controls. Leisure-time physical activity showed a statistically significant inverse association with a crude odds ratio of 0.65 (95% CI 0.45-0.93), even after adjustment for other studied factors (OR =0.63, 95% CI 0.43-0.92). Conversely, for occupational physical activity, a positive association was only suggested.

CONCLUSIONS

Leisure-time physical activity is a protective factor against the development of pancreatic cancer. Occupational physical activity was not confirmed as a protective factor against pancreatic cancer (Tab. 4, Fig. 1, Ref. 22).

A multi-spectroscopic and computational simulations study to delineate the interaction between antimalarial drug hydroxychloroquine and human serum albumin

Hydroxychloroquine (HCQ), a quinoline based medicine is commonly used to treat malaria and autoimmune diseases such as rheumatoid arthritis. Since, human serum albumin (HSA) serves as excipient for vaccines or therapeutic protein drugs, it is important to understand the effect of HCQ on the structural stability of HSA. In this study, the binding mechanism of HCQ and their effect on stability of HSA have been studied using various spectroscopic techniques and molecular dynamic simulation. The UV-VIS results confirmed the strong binding of HCQ with HSA. The calculated thermodynamics parameters confirmed that binding is spontaneous in nature and van der Waals forces and hydrogen bonding are involved in the binding system which is also confirmed by molecular docking results. The steady-state fluorescence confirms the static quenching mechanism in the interaction system, which was further validated by time-resolved fluorescence. The synchronous fluorescence confirmed the more abrupt binding of HCQ with tryptophan residue of HSA compared to Tyr residue of HSA. Isothermal titration calorimetry (ITC) was done to validate the thermodynamics parameters of HSA-HCQ complex in one experiment, supporting the values obtained from the spectroscopic techniques. The circular dichroism (CD) demonstrated that the HCQ affected the secondary structure of HSA protein by reducing their α-helical content. The docking and molecular dynamic simulation results further helped in understanding the effect of HCQ on conformational changes of HSA. Overall, present work defined the physicochemical properties and interaction mechanism of HCQ with HSA that have extensively been elucidated by both in vitro and in silico approaches.

[Pancreatic cancer and lifestyle factors]

BACKGROUND

Pancreatic cancer is a serious cancer with unfavorable prognosis. Due to differences in the incidence of pancreatic cancer in different regions, it is clear that factors associated with lifestyle play an important role in the etiology. The aim of this study was to evaluate the impact of selected lifestyle factors in relation to pancreatic cancer.

MATERIALS AND METHODS

The study included a total of 529 subjects, including 309 cases and 220 control subjects. Cases of newly diagnosed patients with pancreatic cancer who lived in the region were selected in hospitals in three centers (University Hospital Olomouc, University Hospital Ostrava, Hospital Ceske Budejovice). The control group was obtained in cooperation with selected general practitioners for adults, and it is a population control group.

RESULTS

Analyses compared persons who reported consuming alcohol with those who do not consume alcohol. Results showed a statistically significant inverse association, even after adjustment for the other studied factors (OR = 0.57, 95% CI 0.36 to 0.89). When assessing leisure time physical activity, results showed statistically significant inverse association and 35% decrease in the risk (crude OR = 0.65, 95% CI 0.45 to 0.93), and this inverse association was confirmed after adjustment for other studied factors although the result is on the border of statistical significance (adjusted OR = 0.68, 95% CI 0.44 to 1.04). Drinking coffee and tea has only a marginal impact on the occurrence of pancreatic cancer, although the medium and high consumption of black tea was found increased risk by 90 or 44%, respectively. Smoking is considered a causal risk factor for pancreatic cancer, but in this study, a positive association was not found. The study found no statistically significant association between overweight and obesity.

CONCLUSION

Physical activity, dietary measures that will lead to weight loss and education to non-smoking can have a significant impact on the primary prevention of cancer.

Comparative investigation on interaction between potent antimalarials and human serum albumin using multispectroscopic and computational approaches

This study performed a comparative investigation to explore the interaction mechanisms between two potential antimalarial compounds, JMI 346 and JMI 105, and human serum albumin (HSA), a vital carrier protein responsible for maintaining important biological functions. Our aim was to assess the pharmacological efficiency of these compounds while comprehensively analyzing their impact on the dynamic behavior and overall stability of the protein. A comprehensive array of multispectroscopic techniques, including UV-Vis. spectroscopy, steady-state fluorescence analysis, synchronous fluorescence spectroscopy, three-dimensional fluorescence and circular dichroism spectroscopy, docking studies, and molecular dynamics simulations, were performed to probe the intricate details of the interaction between the compounds and HSA. Our results revealed that both JMI 346 and JMI 105 exhibited promising pharmacological effectiveness within the context of malaria therapy. However, JMI 346 was found to exhibit a significantly higher affinity and only minor altered impact on HSA, suggesting a more favorable interaction with the protein on the dynamic behavior and overall stability of the protein in comparison to JMI 105. Further studies can build on these results to optimize the drug-protein interaction and enable the development of more potent and targeted antimalarial treatments.

[A multifactor epidemiological analysis of risk factors for pancreatic cancer in women]

STUDY OBJECTIVE

A multifactor analysis of risk factors for pancreas cancer in women.

MATERIAL AND METHODS

A case-control study was conducted in three centres in the Czech Republic (Olomouc, Ostrava, and České Budějovice) in 2006-2009. In total, 226 women (129 pancreas cancer cases, 97 controls) were included in the study. Statistical analysis was performed, the crude odds ratio (OR) was calculated, and logistic regression analysis was used at a 5% level of statistical significance.

RESULTS

A statistically significant inverse association was found between pancreatic cancer and oral contraceptives (OR 0.21; 95% CI: 0.07-0.69). Pregnancy and number of pregnancies or gynecological surgical procedures did not show any association with pancreatic cancer. No significant difference in the first menstrual period was found between pancreatic cancer patients and controls.

CONCLUSIONS

The study results showed inverse association between pancreatic cancer and oral contraceptives (OR 0.21; 95% CI: 0.07-0.69), controlled alcohol consumption (OR 0.26; 95% CI: 0.12-0.55), and anti-inflamatory drug use (OR 0.10; 95% CI: 0.02-0.41).

Epidemiology, risk factors and possibilities for the prevention of acute leukaemia

Acute leukaemias are malignant diseases of haematopoiesis, traditionally classified according to the affected cell line as acute lymphoblastic and acute myelogenous leukaemia. In terms of incidence, acute leukaemias are rare diseases - in the Czech Republic, only 2-3 new acute myelogenous leukaemia cases/100 000 population are diagnosed annually and less than 1 new case of acute lymphoblastic leukaemia/100 000 residents. The causes of acute leukaemias are still poorly understood. The established risk factors are age, ionizing radiation or Downs syndrome. Moreover, a number of potential risk factors have been described to play a role in development of acute leukaemias and to multiply the risk, such as physical factors, chemicals, genetic and familial predispositions or other diseases. The presented review summarizes the knowledge of the aetiology of acute leukaemias published since 2000. It describes their epidemiological characteristics and risk factors and outlines the possibilities for their prevention.

Recent Updates on Interaction Studies and Drug Delivery of Antimalarials with Serum Albumin proteins

This review focuses on recent trends in the binding study of various antimalarial agents with serum albumins in detail. Serum albumin has a significant role in the transport of drugs and endogenous ligands. The nature and magnitude of serum albumin and drug interactions have a tremendous impact on the pharmacological behavior and toxicity of that drug. Binding of drug to serum albumin not only controls its free and active concentration, but also provides a reservoir for a long duration of action. This ultimately affects drug absorption, distribution, metabolism, and excretion. Such interaction determines the actual drug efficacy as the drug action can be correlated with the amount of unbound drug. With the advancement in spectroscopic techniques and simulation studies, binding studies play an increasingly important role in biophysical and biomedical science, especially in the field of drug delivery and development. This review assesses the insight we have gained so far to improve drug delivery and discovery of antimalarials on the basis of a plethora of drug-serum protein interaction studies done so far.

[The common bed bug (Cimex lectularius) - biology, medical relevance, possibilities for the detection and control]

Bed bugs have become a major concern worldwide in the 21st century and are therefore intensively investigated. The new findings not only extend the knowledge of their biology, medical relevance, and causes of the resurgence, but also can be used in bed bug management. A brief overview is provided of some of the most important research results and opinions, published in the last few years in prestigious international journals.

Biochemistry of Bacterial Biofilm: Insights into Antibiotic Resistance Mechanisms and Therapeutic Intervention

Biofilms, composed of structured communities of bacteria embedded in a self-produced extracellular matrix, pose a significant challenge due to their heightened resistance to antibiotics and immune responses. This review highlights the mechanisms underpinning antibiotic resistance within bacterial biofilms, elucidating the adaptive strategies employed by microorganisms to withstand conventional antimicrobial agents. This encompasses the role of the extracellular matrix, altered gene expression, and the formation of persister cells, contributing to the recalcitrance of biofilms to eradication. A comprehensive understanding of these resistance mechanisms provides a for exploring innovative therapeutic interventions. This study explores promising avenues for future research, emphasizing the necessity of uncovering the specific genetic and phenotypic adaptations occurring within biofilms. The identification of vulnerabilities in biofilm architecture and the elucidation of key biofilm-specific targets emerge as crucial focal points for the development of targeted therapeutic strategies. In addressing the limitations of traditional antibiotics, this review discusses innovative therapeutic approaches. Nanomaterials with inherent antimicrobial properties, quorum-sensing inhibitors disrupting bacterial communication, and bacteriophages as biofilm-specific viral agents are highlighted as potential alternatives. The exploration of combination therapies, involving antimicrobial agents, biofilm-disrupting enzymes, and immunomodulators, is emphasized to enhance the efficacy of existing treatments and overcome biofilm resilience.

Effect of muscle relaxant drug chlorzoxazone on the conformational stability and activity of bovine serum albumin: a spectroscopic and computational study

The commonly used muscle relaxant chlorzoxazone (CZZ) is basic in nature and binds to acidic alpha-1-glycoprotein, affecting the levels of albumins as well as lipoproteins in the body. This can impact the biological half-life of the drug and interfere with its therapeutic requirements. Herein, we have shown the impact of CZZ on the structure of bovine serum albumin (BSA), a transport protein, through various spectroscopic techniques like UV-vis absorption, steady state emission, synchronous fluorescence, and also circular dichroism (CD). Fluorescence results reveal the contribution of hydrogen bonding as well as van der Waal forces for the formation of the complex. Site marker experiments were performed using ibuprofen and indomethacin for site I and site II of BSA, respectively, to understand the competitive binding. UV-visible results show a decrease in absorbance of BSA by the subsequent addition of CZZ and a hypsochromic shift in the spectra. The CD results reveal an increase in BSA's α-helical content in the presence of CZZ, indicating higher folding in the protein's secondary structure. Computational analysis by molecular docking and MD simulations validates the binding of BSA and CZZ and hence, support the experimental findings.

[Epidemiological significance of the metabolic syndrome]

From an epidemiological point of view, the metabolic syndrome is a group of risk factors causally, rather than coincidentally, related to insulin resistance. The metabolic syndrome is a condition with relatively high prevalence rates in both the Czech Republic and in other developed countries. There is a clear trend of increasing prevalence in both sexes depending on age. In the Czech Republic, the syndrome is less common in females (25.5%) than in males (37.6%). Epidemiological studies found white (Europoid race) males to be at higher risk due to abdominal obesity. The definition of the metabolic syndrome has evolved over time and helps to identify individuals at high risk of developing cardiovascular disease and type 2 diabetes, hence the use of the term cardiometabolic syndrome. Early detection of metabolic syndrome symptoms including insulin resistance should be performed mainly by general practitioners as part of regular check-ups.

Epidemiology of hepatitis E virus infection

Hepatitis E is a major concern to public health, it is estimated that 44,000 people die annually due to hepatitis E. Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis in the world. HEV has been found with 7 genotypes, only 4 can infect humans. Genotypes 1 and 2 are major causes of the epidemic and endemic acute hepatitis in developing countries. In the poor hygienic conditions, these genotypes are obligate human pathogens transmitted between humans by the fecal-oral route and via contaminated water. On the contrary, in developed countries, genotypes 3 and 4 are of zoonotic origin and they are transmitted by alimentary route and via direct contact with the infected animal. Transmission by blood, blood products and tissues from infected persons or animals and even mother-to-infant transmission is also possible. Hepatitis E clinical course varies from self-limiting disease to fulminant hepatic failure, and extrahepatic manifestations have occurred. Management to control and prevent this infection is mainly hygienic measures. The provision of clean drinking water and ameliorating the sanitation of human wastes are the most effective preventive approaches as in any infection outbreak transmitted through the fecal-oral route. Nevertheless, dietary habits, distribution of different zoonotic reservoirs and the hygienic level play a crucial role in limiting and preventing the spread of hepatitis E in the developed countries. Although HEV vaccine was developed, it is still available only in China. It protects against genotype 4 with no clear evidence of protection against other genotypes.