Prevention Of Fungal Disease Research Articles

Antifungal activity of lactic acid bacteria from Pangasius catfish culture in the Mekong Delta, Vietnam

Fungi are one of the most common pathogens in aquaculture. The study was performed to isolate and select lactic acid bacteria (LAB) with antifungal activity. A total of 36 isolates of LAB were isolated from the intestines of Pangasianodon hypophthalmus, water and sludge, fermented vegetables, and “com me” in Vinh Long province of the Mekong Delta, Vietnam. The results revealed that the isolated LAB isolates were inhibitory against five species of fungi: Aspergillus sp., Fusarium sp., Achlya sp., Saprolegnia sp., and Mucor sp. In particular, isolate LN12 showed the highest activity against Aspergillus sp., Fusarium sp., Achlya sp., Saprolegnia sp., and Mucor sp. with inhibition diameters of 20 mm, 19.33 mm, 19.67 mm, 19.0 mm, and 20.33 mm, respectively. An investigation on the influence of culture conditions showed that all four bacterial isolates, LN5, LN12, LN23, and LN31, had the highest antifungal activity at a concentration of 108 CFU/ml after incubation for 48-60 hours, incubation temperature of 30–35oC, pH of 5.0–6.0 in the medium without the addition of NaCl. Four bacterial isolates, LN5, LN12, LN23, and LN31, were identified as Lactobacillus, and LN33 belonged to Pediococcus based on morphological and biochemical characteristics, and 16S-rRNA gene sequencing. The results show the potential application of LAB isolates in the prevention of fungal diseases in catfish.

Pan-Indian Clinical Registry of Invasive Fungal Infections Among Patients in the Intensive Care Unit: Protocol for a Multicentric Prospective Study.

Fungal infections are now a great public health threat, especially in those with underlying risk factors such as neutropenia, diabetes, high-dose steroid treatment, cancer chemotherapy, prolonged intensive care unit stay, and so on, which can lead to mycoses with higher mortality rates. The rates of these infections have been steadily increasing over the past 2 decades due to the increasing population of patients who are immunocompromised. However, the data regarding the exact burden of such infection are still not available from India. Therefore, this registry was initiated to collate systematic data on invasive fungal infections (IFIs) across the country. The primary aim of this study is to create a multicenter digital clinical registry and monitor trends of IFIs and emerging fungal diseases, as well as early signals of any potential fungal outbreak in any region. The registry will also capture information on the antifungal resistance patterns and the contribution of fungal infections on overall morbidity and inpatient mortality across various conditions. This multicenter, prospective, noninterventional observational study will be conducted by the Indian Council of Medical Research through a web-based data collection method from 8 Advanced Mycology Diagnostic and Research Centers across the country. Data on age, gender, clinical signs and symptoms, date of admission, date of discharge or death, diagnostic tests performed, identified pathogen details, antifungal susceptibility testing, outcome, and so on will be obtained from hospital records. Descriptive and multivariate statistical methods will be applied to investigate clinical manifestations, risk variables, and treatment outcomes. These Advanced Mycology Diagnostic and Research Centers are expected to find the hidden cases of fungal infections in the intensive care unit setting. The study will facilitate the enhancement of the precision of fungal infection diagnosis and prompt treatment modalities in response to antifungal drug sensitivity tests. This registry will improve our understanding of IFIs, support evidence-based clinical decision-making ability, and encourage public health policies and actions. Fungal diseases are a neglected public health problem. Fewer diagnostic facilities, scanty published data, and increased vulnerable patient groups make the situation worse. This is the first systematic clinical registry of IFIs in India. Data generated from this registry will increase our understanding related to the diagnosis, treatment, and prevention of fungal diseases in India by addressing pertinent gaps in mycology. This initiative will ensure a visible impact on public health in the country. DERR1-10.2196/54672.

Containment of Fusarium culmorum and Its Mycotoxins in Various Biological Systems by Antagonistic Trichoderma and Clonostachys Strains.

Prevention of fungal diseases caused by Fusarium species, including F. culmorum, and thus the accumulation of mycotoxins in wheat ears, is a constant challenge focused on the development of new, effective crop management solutions. One of the currently most ecologically attractive approaches is biological control using natural antagonistic microorganisms. With this in mind, the antagonistic potential of thirty-three Clonostachys and Trichoderma strains was assessed in this work. Screening tests were carried out in in vitro cultures, and the observed potential of selected Trichoderma and Clonostachys strains was verified in field and semi-field experiments with two forms of wheat: winter cv. Legenda and spring cv. Bombona. Three strains, namely C. rosea AN291, T. atroviride AN240 and T. viride AN430 were reported to be most effective in inhibiting the growth of F. culmorum KF846 and the synthesis of DON, 3AcDON and ZEN under both laboratory and semi-controlled field conditions. Observations of the contact zones of the tested fungi in dual cultures exposed their mycoparasitic abilities against KF846. In addition, studies on liquid cultures have demonstrated the ability of these strains to eliminate F. culmorum toxins. Meanwhile, the strains of T. atroviride AN35 and T. cremeum AN392 used as soil inoculants in the field experiment showed a different effect on the content of toxins in ears (grains and chaffs), while improved wheat yield parameters, mainly grain health in both wheat cultivars. It is concluded that the selected Trichoderma and Clonostachys strains have a high potential to reduce the adverse effects of F. culmorum ear infection; therefore, they can be further considered in the context of potential biocontrol factors and as wheat crop improvers.

Tetrahydroisoquinoline N-methyltransferase from Methylotenera Is an Essential Enzyme for the Biodegradation of Berberine in Soil Water.

Berberine (BBR), a Chinese herbal medicine used in intestinal infection, has been applied as a botanical pesticide in the prevention of fungal disease in recent years. However, its degradation in the environment remains poorly understood. Here, we investigated BBR’s degradation in soil water from different sources accompanied by its effect on bacterial diversity. Our results indicated that BBR was only degraded in soil water, while it was stable in tap water, river water and aquaculture water. Bacterial amplicon results of these samples suggested that the degradation of BBR was closely related to the enrichment of Methylotenera. To reveal this special relationship, we used bioinformatics tools to make alignments between the whole genome of Methylotenera and the pathway of BBR’s degradation. An ortholog of Tetrahydroisoquinoline N-methyltransferase from plant was discovered only in Methylotenera that catalyzed a crucial step in BBR’s degradation pathway. In summary, our work indicated that Methylotenera was an essential bacterial genus in the degradation of BBR in the environment because of its Tetrahydroisoquinoline N-methyltransferase. This study provided new insights into BBR’s degradation in the environment, laying foundations for its application as a botanical pesticide.

Research progress on prevention and treatment of invasive fungal diseases in patients with hematological malignancies

The incidence of invasive fungal disease (IFD) is high in patients with hematological malignancies, including those with acute myeloid leukemia(AML)/myelodysplastic syndrome(MDS), and those receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT). IFD is an important prognostic factor in patients with hematological malignancies. IFD is difficult to diagnose, and the efficacy of treatment is poor. Therefore, antifungal treatment begins with prevention. At present, there are still controversies about the clinical indications, drugs, administration time and efficacy of IFD chemoprevention. This article intends to review the research progress on the epidemiology and risk factors of IFD, as well as the clinical outcomes of antifungal agents for antifungal prophylaxis in patients with hematological malignancies. Key words: Antifungal agents; Hematologic neoplasms; Epidemiologic studies; Chemoprevention; Invasive fungal disease

An Outbreak of Febrile Histoplasmosis Among Chinese Manganese-Mine Workers in Cooperative Republic of Guyana in 2019

What is already known on this topic? Cases of histoplasmosis have been reported in every continent except Antarctica but are fairly rare in China. High prevalence of histoplasmosis has been observed in Central America, Caribbean, and South America. Infections of Histoplasma are acquired through a respiratory route, particularly inhalation of aerosols from disturbed soils enriched with excreta from birds and bats. These infections are most common in persons involved with removing soil, visiting caves, cleaning old houses, or felling trees, etc. What is added by this report? This is the first report of cluster infections of Histoplasma among overseas Chinese workers. A strong dose-dependent association of illness onset and disease severity with the exposure intensity to the soils and wastes possibly contaminated by the Histoplasma has been proposed. Long labor times, repeated entering of contaminated tunnels, working in high-dust environments are likely to result in earlier illness onsets, more severe clinical courses, and even fatal outcomes. More importantly, none of the patients used reliable personal protection equipment (PPE), such as common masks while working, that would prevent the inhalation of more Histoplasma spores. What are the implications for public health practice? The epidemiological findings of this outbreak investigation highlight a probable risk of infection with Histoplasma when entering without PPE into the environment with bats living around, such as caves or mines. Effective education and communication might be needed among residents and travelers. This outbreak expands our knowledge of the control and prevention of fungal disease in China.

Application of posaconzole in prophylactic antifungal treatment of patients with hematological malignancies

Objective To observe the effect and safety of posaconzole in prophylactic antifungal treatment of high-risk patients with hematological malignancies. Methods The effect of posaconzole on prevention of invasive fungal disease (IFD) during chemotherapy in 102 patients with hematological malignancies in Shanghai Ruijin Hospital from February 2014 to April 2017 were analyzed retrospectively. The correlation analysis was carried out by Spearman analysis. Results A total of 102 patients were included, and only 2 (1.96%) patients had IFD. 2 patients died because of development of hematological malignancies. 11 (10.8%) patients had to discontinuation of posaconzole because of sever adverse events. Two patients with IFD and 1 case of undiagnosed IFD had to discontinue posaconzole. The total rate of discontinuation was 13.7% (14/102). There was no correlation between the time of using pothiazol and the time of hospitalization (rs=-0.02, P= 0.853) and the time of neutrophilic deficiency (rs= 0.167, P= 0.113), but the time of hospitalization was positively correlated with the time of neutrophilic deficiency (rs= 0.448, P= 0.000). Conclusion Posaconzole could effectively and safely prevent IFD in patients with hematological malignancies. Key words: Hematological neoplasms; Mycoses; Posaconzole

Antimycotic activity of fengycin C biosurfactant and its interaction with phosphatidylcholine model membranes

Lipopeptide biosurfactants constitute one of the most promising groups of compounds for the treatment and prevention of fungal diseases in plants. Bacillus subtilis strain EA-CB0015 produces iturin A, fengycin C and surfactin and it has been proven useful for the treatment of black Sigatoka disease in banana plants, an important pathology caused by the fungus Mycosphaerella fijiensis (Morelet). We have found that B. subtilis EA-CB0015 cell free supernatants and purified fractions inhibit M. fijiensis cellular growth. The effect of the purified lipopeptides mentioned above on fungal growth has been also evaluated, observing that iturin A and fengycin C inhibit mycelial growth and ascospore germination, whereas surfactin is not effective. On the hypothesis that the antifungal action of the lipopeptides is associated to their incorporation into biological membranes, ultimately leading to membrane permeabilization, a detailed biophysical study on the interaction of a new isoform of fengycin C with model dipalmitoyphosphatidylcholine (DPPC) membranes has been carried out. Differential scanning calorimetry shows that fengycin C alters the thermotropic phase transitions of DPPC, and is laterally segregated in the fluid bilayer forming domains. Fluorescent probe polarization measurements show that fengycin C does not affect the hydrophobic interior of the membrane. This latter perturbation is concomitant with a strong dehydration of the polar region of DPPC, as shown by FTIR. Fengycin-rich domains, where the surrounding DPPC molecules are highly dehydrated, may well constitute sites of membrane permeabilization leading to a leaky target membrane. These results are a solid support to explain the membrane perturbing action of fengycin, which has been related to its antifungal activity.

Polymeric and Solid Lipid Nanoparticles for Sustained Release of Carbendazim and Tebuconazole in Agricultural Applications.

Carbendazim (MBC) (methyl-2-benzimidazole carbamate) and tebuconazole (TBZ) ((RS)-1-(4-chlorophenyl)-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)pentan-3-ol) are widely used in agriculture for the prevention and control of fungal diseases. Solid lipid nanoparticles and polymeric nanocapsules are carrier systems that offer advantages including changes in the release profiles of bioactive compounds and their transfer to the site of action, reduced losses due to leaching or degradation, and decreased toxicity in the environment and humans. The objective of this study was to prepare these two types of nanoparticle as carrier systems for a combination of TBZ and MBC, and then investigate the release profiles of the fungicides as well as the stabilities and cytotoxicities of the formulations. Both nanoparticle systems presented high association efficiency (>99%), indicating good interaction between the fungicides and the nanoparticles. The release profiles of MBC and TBZ were modified when the compounds were loaded in the nanoparticles, and cytotoxicity assays showed that encapsulation of the fungicides decreased their toxicity. These fungicide systems offer new options for the treatment and prevention of fungal diseases in plants.

Treatment of fungal infections: an update

Fungal infections represent a serious problem in neonatal intensive care units (NICUs) worldwide. Preterm infants are a vulnerable population for major events and adverse sequelae from fungal sepsis. The primary fungus of concern in neonates is C. albicans , whose colonization is associated with devastating complication and high rate of mortality. Among the risk factors responsible for development of invasive fungal infections, previous mucosal and skin colonization are of primary importance. Fungal colonization in neonates may be secondary to either maternal transmission or nosocomial acquisition in the nursery. Antifungal prophylaxis is currently applied in different NICUs and in various patients groups with successful results. Prophylactic drugs can include oral nystatin and oral or intravenous fluconazole. To date, antifungal prophylaxis with fluconazole is the recommended approach for neonates lower than 1,000 g and/or 27 weeks’ gestation or less, manly in NICUs with relatively high frequency of invasive candidiasis. First-line treatment of invasive fungal infections includes amphotericin B deoxycholate, lipid preparations of amphotericin B, fluconazole, or micafungin. However, data on pharmacokinetic, schedule treatment and appropriate dosage of antifungal agents in neonates, mainly in premature, are still limited. Future strategies to reduce neonatal morbidity and mortality derived from invasive fungal infections include new echinocandins not yet approved for neonatal use (caspofungin or anidulafungin) and other adjuvant treatments as intravenous immunoglobulin, lactoferrin or probiotics. Since current therapies for systemic fungal diseases are not universally successful and morbidity remains high, future efforts will be also focused on better prevention of fungal diseases and understanding of appropriate dosing schedule of the available antifungal agents. Proceedings of the 10 th International Workshop on Neonatology · Cagliari (Italy) · October 22 nd -25 th , 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

Fungal diseases of some vegetables grown in greenhouse and garden

Aim of this paper was to give an overview of fungal diseases prevailing on the most common vegetables grown in Novi Sad area. For investigation, lettuce and spinach grown in a greenhouse and in open garden were chosen. In greenhouse, optimal conditions for growing lettuce and spinach were maintained, which at the same time favor the development of fungal diseases. The vegetables grown in a protected suburban open garden were more problematic considering fungal diseases. In this paper, the prevention of fungal diseases was emphasized to avoid drastic chemical treatment or minimize its application. The adequate prevention in greenhouse is a good ecological measure.