Understanding In-Silico Approaches to Design Synthetic Antifungal Peptides to Combat Fungal Infections like Mucormycosis

Antimicrobial peptides are the small sized molecule ranging in size from 2 to 9 kDa with expansive range of antimicrobial activity against bacteria, fungi, viruses etc. They are also used as first line of defense against various pathogens. With the emergence of various fungal infections in the present day and uprising antifungal resistance has made the choice of antifungal drugs very limited, the conventional drugs are slowly becoming ineffective to these fungal pathogens. Researchers have turned to these naturally occurring molecules which represent diverse range of functions and structural features but these naturally occurring peptides exhibit high toxicity, instability and low specificity towards the target which can be combatted by using various in silico and computational approaches to design and modify these AMPs in such a way that their efficiency is increased. In this article, we have specifically focused on Mucormycosis infection because of its high mortality rates and a very few synthetic AMPs have been produced against Mucorales considering the severity of this disease and the rapid surge in Mucormycosis cases emerged in the country. In this paper we will discuss about the present scenario of the disease, AMPs as antifungal therapy, role, classification of antifungal peptides, mechanism of action, advantages and limitations of natural AMPs, important physicochemical properties taken into account while designing synthetic AMPs (SAMPs) and the workflow pipeline to characterize and predict potential synthetic AMPs by using the existing web servers, databases and bioinformatics tools to develop new alternatives of conventional drugs available in the market against fungal infections.

Laboratory-based Evaluation of Wondfo HIV1/2 Rapid Test Kits in the Gambia, December 2020

Background: HIV rapid diagnosis in The Gambia is mainly done using Determine HIV-1/2 and First Response HIV 1.2.0 or SD Bioline HIV-1/2 3.0 for screening and sero-typing of HIV respectively among children and adults. Polymerase Chain Reaction (PCR) is used for the detection of the HIV viral genome among infants born to HIV positive mothers. This is the HIV testing Algorithm recommended in the HIV testing guidelines of The Gambia for both HIV Counseling and Testing (HCT), Prevention of Mother-to-Child Transmission of HIV (PMTCT) as well as other clinical requests for HIV testing. At the National Public Health Reference Laboratories (NPHRL), ELISA is the first line of testing for HIV while First Response HIV 1.2.0 or SD Bioline HIV 1/2 3.0 is used for preliminary serotyping. MP Diagnostics HIV Blot 2.2 Western Assay, which is the gold standard for HIV testing in The Gambia, is used as the tie breaker (i.e., when there are discordant results). The aim of this study was to evaluate the sensitivity and specificity of the Wondfo HIV 1/2 rapid test kit for the detection of human antibodies to HIV in serum/plasma/whole blood and dried blood spots. Methods: The sensitivity, specificity, positive and negative predictive values of Wondfo HIV 1/2 kits were evaluated in terms of HIV screening against Determine HIV1/2, GenScreen Ultra HIV Ag-Ab ELISA and First Response HIV 1.2.0 using a total of 401 samples. Of these, 351 were sera/plasma samples {100 HIV negative, 250 HIV positive and 1 indeterminate that were stored at -20°C, 26 were whole blood samples (4 negative, 22 positive), and 24 were dried blood spot (DBS) specimens (16 negative and 8 positive) were used for this evaluation. HIV positive specimens were previously sero-typed using First Response HIV-1.2.0 test cards and MP Diagnostics HIV Blot 2.2 Western Assay. Results: The evaluation shows that the sensitivity, specificity, positive and negative predictive values of Wondfo HIV 1/2 Test Kits with regards to HIV Screening when compared with the GenScreen Ultra HIV Ag-Ab ELISA and First Response 1.2.O (n=401) were 100%, 100%, 100%, and 100% respectively. Similarly, the sensitivity, specificity, positive and negative predictive values of Wondfo HIV 1/2 Test Kits with regards to HIV Screening compared to Determine HIV1/2 (n=401) were 99.64%, 100%, 100%, and 99.17% respectively. Conclusions: This study demonstrates that Wondfo HIV 1/2 test kits have a high sensitivity and specificity when used for the detection of HIV antibodies using human serum/plasma, whole blood or DBS.

Isolated Mycobacterium Tuberculosis Tenosynovitis and Osteomyelitis of the Foot in an Immunocompetent Patient

Tubercular osteomyelitis must be considered in the differential diagnosis of immunocompetent patients who present with non-healing wounds with underlying osteomyelitis. Clinical and radiological findings may be indistinguishable from typical bacteria osteomyelitis. A high index of suspicion may prevent delayed diagnosis, and early treatment may prevent subsequent complications. This is a case report of an immunocompetent patient who presented with a chronic non-healing foot wound complicated by abscess and osteomyelitis that did not improve with an appropriate course of intravenous antibiotics. Wound cultures subsequently grew Mycobacterium tuberculosis without evidence of pulmonary involvement. The patient was treated with an initial two-month regimen of rifampin, isoniazid, pyridoxine, pyrazinamide and ethambutol, followed by a tenmonth regimen of rifampin, isoniazid and pyridoxine. The patient experienced significant improvement and complete healing of the foot wound after approximately the first two months of therapy.

Mucormycosis in a Patient with Chronic Lymphatic Leukemia in Treatment with Ibrutinib

Invasive Fungal Infection (IFI) is a serious complication in patients with hematologic malignancies. We present a case of invasive Mucormycosis in a patient with Chronic Lymphatic Leukemia (CLL). This case of Mucormycosis illustrates invasive fungal infections as a complication to chronic hematologic diseases and adds to other publications that suggest a relationship with novel treatments of CLL such as ibrutinib. Treatment of the IFI was successful without having to stop ibrutinib. We present relevant publications and discuss clinical controversies that arise.

Bacterial and Fungal Co-Infections in Patients with COVID-19 Related Pneumonia: A Retrospective Cohort Study

Background: The study analyzed risk factors for bacterial and fungal coinfection in patients with COVID-19 and the impact on mortality. Methods: This is a single-center retrospective study conducted on 387 patients with confirmed COVID-19 pneumonia admitted to an Italian Tertiarycare hospital, between 21 February 2020 and 31 May 2020. Bacterial/fungal coinfection was determined by the presence of characteristic clinical features and positive culture results. Multivariable logistic regression was used to analyze risk factors for the development of bacterial/fungal co-infection after adjusting for demographic characteristics and comorbidities. Thirty-day survival of the patients with or without co-infections was analyzed by Kaplan- Meier method. Results: In 53/387 (13.7%) patients with COVID-19 pneumonia, 67 episodes of bacterial/fungal co-infection occurred (14 presented >1 episode). Pneumonia was the most frequent co-infection (47.7%), followed by BSI (34.3%) and UTI (11.9%). S. aureus was responsible for 24 episodes (35.8%), E. coli for 7 (10.4%), P. aerugionsa and Enterococcus spp. for 5 episodes each (7.4%). Five (7.4%) pulmonary aspergillosis, 3 (4.4%) pneumocystosis and 5 (7.4%) invasive candidiasis were observed. Multivariable analysis showed a higher risk of infection in patients with an age >65 years (csHR 2.680; 95% CI: 1.254-5.727; p=0.054), with cancer (csHR 5.243; 95% CI: 1.173-23.423; p=0.030), with a LOS >10 days (csHR 12.507; 95% CI: 2.659 - 58.830; p=0.001), early (within 48h) admitted in ICU (csHR 11.766; 95% CI: 4.353-31.804; p<0.001), and with a SOFA score >5 (csHR 3.397; 95% CI: 1.091-10.581; p=0.035). Estimated cumulative risk of developing at least 1 bacterial/fungal co-infection episode was of 15% and 27% after 15 and 30 days from admission, respectively. Kaplan-Meier estimated a higher cumulative probability of death in patients with bacterial/fungal co-infection (log-rank=0.031). Thirty-day mortality rate of patients with pneumonia was 38.7%, higher than those with BSI (30.4%). Conclusions: Bacterial and fungal infections are a serious complication affecting the survival of patients with COVID-19- related pneumonia. Some issues need to be investigated, such as the best empirical antibiotic therapy and the need for possible antifungal prophylaxis.

Candida albicans Secreted Aspartic Protease 7 is Essential for Damage of Human Oral Epithelial Cells

Aims: Candida albicans is an important human fungal pathogen in clinical settings. It possesses a wide spectrum of virulence traits, including but not limited to the production of Secreted Aspartic Proteases (SAPs), to invade host cells under predisposing conditions. The aims of the present study were to investigate the functional role of C. albicans SAP7 in invasion ability. Methods: The present study was carried out to construct C. albicans sap7Δ/Δ mutant strain using a PCR-based gene disruption method. The behaviors of this SAP7 knockout strain was evaluated and compared with the wild type and SAP7 complemented strains between human oral epithelial cells with respect to endocytosis, invasion, and tissue damage. Results: Compared with the wild type C. albicans strain, a 52% reduction in the endocytosis of the sap7Δ/Δ mutant strain by oral epithelial cells was observed, as well as a 25% attenuation of internalization, and a 27% reduction of tissue damage (P<0.05). Conclusion: Our data clearly demonstrates that C. albicans SAP7 contributes to tissue invasion into human oral epithelial cells which warrant further investigations as potential targets for antifungal interventions.

Comparing Quantitative and Qualitative Methods for Detecting the In Vitro Activity of Colistin against Different Gram-Negative Bacilli

The surge in the prevalence of Multidrug-Resistant (MDR) Gram-negative bacterial infections with limited treatment led to colistin reusing to treat MDR infections. This study aimed to determine economical, simple, and reliable colistin susceptibility testing methods as an alternative to the microdilution technique. We compared seven colistin susceptibility testing methods, including quantitative and qualitative, namely: Disk diffusion, E-test, ComASPTM SensiTest Colistin, Colistin broth disk elution, and colistin agar test CHROMagarTM COL-APSE, and BD Phoenix ID/AST automated identification and susceptibility testing system to the gold standard Broth Microdilution (BMD). Whole-genome sequencing was performed on all isolates to determine if the genetic resistant factors affect the phenotypic profile of the colistin resistance. Our results revealed that disk diffusion is still an ineffective method for measuring colistin susceptibility in Gram-negative Bacilli with the highest major error (31.75%), the lowest Kappa 0 (0%), and categorical agreement (68.25%) values. Phoenix, and CompASPTM SensiTest colistin methods have remained superior in reproducibility, sturdiness, and simplicity of use, similar to the currently recommended broth microdilution procedure; with high sensitivity of 95.56%, and 97.73%, specificity of 95.24, and 100%, and Kappa values of 0.89 and 0.95, respectively. This study revealed that Phoenix, and ComASPTM SensiTest colistin methods are recommended for routine microbiology laboratories with a large workload.

Microbial Cellulases: A Review on Strain Development, Purification, Characterization and their Industrial Applications

In this advance era, the enzymes are considered as a core kernel of white biotechnology and their demand is increasing day by day. According to report published in Research and Markets (ID: 5009185), the estimated global market for industrial enzymes were USD 10.0 billion in 2019, which is continuously increasing as it is expected to reach about USD 14.7 billion by 2022. Among all enzymes, cellulases are the major group of enzymes act synergistically in breakdown of cellulose, that facilitates its conversion to various value-added products and also offer several other important applications at industrial scale. The hyper production of cellulases are required to overcome their demand of global market. Cellulases production can be enhanced by strain improvement as well as using advance fermentation technology. In this review a detail studies of strategies to enhance production of cellulases and improve their physiochemical properties for industrial application have been described.

Cryptococcus neoformans Virulence Attributes can be Modulated by Sound Stress

Sound waves are a prime component making up the environment, and they are present in almost all niches on the planet. In times of increasing noise pollution, the effect of sound stress on humans, animals, and microorganisms is well known. However, the possibility of this kind of pressure in the environment, affecting pathogenic fungi, which live in the background as saprophytes, has not been explored. Fungi can develop attributes and become virulent due to adaptation to selective pressure or stress. In this context, our group has become interested in evaluating the impact of sound stress on the fungus Cryptococcus neoformans, a pathogen that has high phenotypic plasticity. C. neoformans strain H99 was chosen for all assays. The yeasts were cultivated at 30°C, exposed or not to the frequency of 8 kHz. We observed morphological changes in these cells, such as the expression of phenotype virulence attributes: capsule expansion and melanin production. We also analyzed the number of viable cells after exposure, and we observed the yeast’s susceptibility to antifungals. After the treatment with 8 kHz, the cells showed a significant increase in the capsule expansion, an acceleration of the melanin production, and a slight reduction in the number of viable cells. Finally, tests performed with the antifungals showed a decrease in inhibition halo on the plate test. Our results are innovative and suggest that stress caused by sound could incite increased virulence in this fungus.

Evaluation of the Efficacy of the Combination of Hydroxychloroquine and Azithromycin in the Treatment of Covid-19 in a Moroccan Population

Context: Morocco has adopted the protocol combining hydroxychloroquine or chloroquine with azithromycin to treat patients with Covid-19, mainly based on Chinese studies and those of the IHU Mediterranee team in Marseille. The objective of this study is to assess the effectiveness of this association in a Moroccan population. Methods: We conducted a prospective descriptive analytical study at the center of virology, infectious and tropical diseases to assess the efficacy of hydroxychloroquine associated with azithromycin for the treatment of patients with Covid-19. All patients hospitalized at the center between March 16, 2020 and May 16, 2020 were included in this study with a positive RT-PCR result for SARS-Cov2. Results: 125 patients were hospitalized during this period meeting the inclusion criteria. All patients benefited from the combination of hydroxychloroquine and azithromycin. We studied the clinical, biological and CT parameters that could be associated with early viral clearance with a negative RT-PCR on D6 and D8. The average age at diagnosis is 37.98 +/- 12.13 years. 121 patients (96.8%) are cured after 10 days of treatment. 32 patients (25.6%) had a viral clearance on D6 and D8. We did not find any factors significantly associated with early viral clearance. Conclusion: Our study is inconsistent with work published by other teams regarding early viral clearance in patients treated with the combination of hydroxychloroquine and azithromycin, although clinical healing has been achieved in the majority of patients.