Prevalence and correlates of urogenital schistosomiasis in school-going children at Maramba Primary School in Livingstone District, Zambia.

OBJECTIVES: To determine the presence and correlates of S. haematobium in urine specimens of school-going children at Maramba Primary School in Livingstone, Zambia. METHODS AND SUBJECTS: A structured questionnaire was administered to children with signed consent from their guardians/parents, and spot urine specimens were collected in sterile containers for macroscopic/microscopic examination by an experienced laboratory technologist. RESULTS: A total of 173 school-going children participated in the study. Parasitic eggs were detected in six specimens with prevalence of 3.47 %, which was strongly associated with presence of microscopic red blood cells (p < 0.01) and washing clothes in a stream (p = 0.01). CONCLUSION: Low prevalence of urogenital schistosomiasis among school-going children was noted with correlates such as washing in a stream, while an older age group showed much stronger disease association.

Antibiotic susceptibility patterns of pathogens isolated from laboratory specimens at Livingstone Central Hospital in Zambia.

BACKGROUND: Multidrug resistance (MDR) is a global problem that require multifaceted effort to curb it. This study aimed to evaluate the antibiotic susceptibility patterns of routinely isolated bacteria at Livingstone Central Hospital (LCH). METHODS: A retrospective study was performed on all isolated organisms from patient specimens that were processed from January 2019 to December 2021. Specimens were cultured on standard media and Kirby-Bauer disc diffusion method was employed for susceptibility testing following the Clinical and Laboratory Standard Institute's recommendations. RESULTS: A total of 765 specimens were processed and only 500 (65.4%) met the inclusion criteria. Of the 500, 291(58.2%) specimens were received from female and from the age-group 17-39 years (253, 50.6%) and 40-80 years (145, 29%) in form of blood (331, 66.2%), urine (165, 33%) and sputum (4, 0.8%). Amongst the bacterial isolates, Staphylococcus aureus (142, 28.4%) was the commonest followed by Escherichia coli (91, 18.2%), and Enterobacter agglomerans (76, 15.2%), and Klebsiella pneumoniae (43, 8.6%). The resistance pattern revealed ampicillin (93%) as the least effective drug followed by oxacillin (88%), penicillin (85.6%), co-trimoxazole (81.5%), erythromycin (71.9%), nalidixic acid (68%), and ceftazidime (60%) whereas the most effective antibiotics were imipenem (14.5%), and piperacillin/tazobactam (16.7%). The screening of methicillin resistant Staphylococcus aureus (MRSA) with cefoxitin showed 23.7% (9/38) resistance. CONCLUSION: Increased levels of MDR strains and rising numbers of MRSA strains were detected. Therefore, re-establishing of the empiric therapy is needed for proper patient management, studies to determine the levels of extended spectrum beta lactamase- and carbapenemase-producing bacteria are warranted.

Expression and in vitro anticancer activity of Lp16-PSP, a member of the YjgF/YER057c/UK114 protein family from the mushroom Lentinula edodes C91-3.

Latcripin-16 (Lp16-PSP) is a gene that was extracted as a result of de novo characterization of the Lentinula edodes strain C91-3 transcriptome. The aim of the present study was to clone, express, and investigate the selective in vitro anticancer potential of Lp16-PSP in human cell lines. Lp16-PSP was analyzed using bioinformatics tools, cloned in a prokaryotic expression vector pET32a (+) and transformed into E. coli Rosetta gami. It was expressed and solubilized under optimized conditions. The differential scanning fluorometry (DSF)-guided refolding method was used with modifications to identify the proper refolding conditions for the Lp16-PSP protein. To determine the selective anticancer potential of Lp16-PSP, a panel of human cancerous and non-cancerous cell lines was used. Lp16-PSP protein was identified as endoribonuclease L-PSP protein and a member of the highly conserved YjgF/YER057c/UK114 protein superfamily. Lp16-PSP was expressed under optimized conditions (37 °C for 4 h following induction with 0.5 mM isopropyl ß-D-1-thiogalactopyranoside). Solubilization was achieved with mild solubilization buffer containing 2 M urea using the freeze-thaw method. The DSF guided refolding method identified the proper refolding conditions (50 mM Tris-HCl, 100 mM NaCl, 1 mM EDTA, 400 mM Arginine, 0.2 mM GSH and 2 mM GSSG; pH 8.0) for Lp16-PSP, with a melting transition of ~ 58 °C. A final yield of ~ 16 mg of purified Lp16-PSP from 1 L of culture was obtained following dialysis and concentration by PEG 20,000. A Cell Counting Kit-8 assay revealed the selective cytotoxic effect of Lp16-PSP. The HL-60 cell line was demonstrated to be most sensitive to Lp16-PSP, with an IC50 value of 74.4 ± 1.07 µg/ml. The results of the present study suggest that Lp16-PSP may serve as a potential anticancer agent; however, further investigation is required to characterize this anticancer effect and to elucidate the molecular mechanism underlying the action of Lp16-PSP.

Evaluation of antibiotic susceptibility patterns of pathogens isolated from routine laboratory specimens at Ndola Teaching Hospital: A retrospective study.

Periodic monitoring of antibiotic susceptibility patterns in clinical settings is vital to ascertain the potency as well as re-establishing empirical therapy. This retrospective study aimed to evaluate the antibiotic susceptibility patterns of pathogens isolated from routine laboratory specimens at Ndola Teaching Hospital. A retrospective study was conducted on routine specimens received between May 2016 and July 2018. Specimens were cultured on standard media and Kirby-Bauer disc diffusion method was used for susceptibility testing in accordance with the Clinical and Laboratory Standard Institute's recommendations. A total of 693 specimens were analyzed, of which 65.9% (457) specimens came from inpatient departments and 49.1% (340) came from female patients. The commonest specimens were urine (58.6%), blood (12.7%) and wound swabs (8.5%), and the most common microorganisms were coliform (29.3%), Staphylococcus aureus (15.4%), coagulase negative Staphylococci (CoNS, 13.4%), and Escherichia coli (13%). The highest percentage of resistance to any particular antibiotic was co-trimoxazole (91.7%, 33) followed by nalidixic acid (75.2%, 279), norfloxacin (69.0%, 100), ceftazidime (55.7%, 185), nitrofurantoin (46.6%, 191), chloramphenicol (43%, 111) and ciprofloxacin (8.6%, 271). Furthermore, patient location had resistance effect on coliform (p = 0.014), CoNS (p = 0.031), Streptococcus species (p = 0.024) and Klebsiella species (p = 0.004) to nitrofurantoin, ceftazidime, nitrofurantoin and chloramphenicol, respectively. Besides coliform, resistance of Enterobacter species to ceftazidime and Proteus species to nalidixic acid were more from female patients. Generally, the most effective antibiotics were chloramphenicol and nitrofurantoin with addition of ceftazidime on blood pathogens and ciprofloxacin on wound swab pathogens. The common isolates were coliform, S. aureus, coagulase negative Staphylococci and Escherichia coli. The resistance of most bacteria to ceftazidime and nitrofurantoin were influenced by both gender and location. Our study presents a broad overview of the resistance profiles of bacterial isolates. However, more nosocomial prevalence and antibiogram studies on individual routine specimens are required to provide a more detailed picture of resistance patterns.

Antibacterial and anti-biofilm activity of the lipid extract from Mantidis ootheca on Pseudomonas aeruginosa.

The aim of this study is to assess the antibacterial and anti-biofilm properties of the lipid extract from Mantidis ootheca against the gentamycin resistant Pseudomonas aeruginosa. The chemical composition of the lipid extract and its relative proportion were determined using the technique of gas chromatography coupled with mass spectrometry (GC-MS). Antibacterial susceptibility tests were performed using a disc diffusion assay and the minimum inhibition concentration (MIC) was determined by way of the agar dilution method. The anti-biofilm test was carried out with crystal violet staining and scanning electron microscopy (SEM). There were 16 compounds detected, and the most abundant components were sesquiterpenoids, monoterpenes, and trace aromatic compounds. The MIC for P. aeruginosa was 4 mg/ml and the eradication effect on preformed biofilms was established and compared with a ciprofloxacin control. The results of our study indicated that a lipid extract from M. ootheca could be used as a topical and antibacterial agent with anti-biofilm activity in the future.

Effectiveness of omega-3 polyunsaturated fatty acids against microbial pathogens.

Microorganisms provide both beneficial and harmful effects to human beings. Beneficial effects come from the symbiotic relationship that exists between humans and microbiota, but then several human illnesses have turned some friendly microbes into opportunistic pathogens, causing several microbial-related diseases. Various efforts have been made to create and utilize antimicrobial agents in the treatment and prevention of these infections, but such efforts have been hampered by the emergence of antimicrobial resistance. Despite extensive studies on drug discovery to alleviate this problem, issues with the toxicity and tolerance of certain compounds and continuous microbial evolution have forced researchers to focus on screening various phytochemical dietary compounds for antimicrobial activity. Linolenic acid and its derivatives (eicosapentaenoic acid and docosahexaenoic acid) are omega-3 fatty acids that have been studied due to their role in human health, being important for the brain, the eye, the cardiovascular system, and general human growth. However, their utilization as antimicrobial agents has not been widely appreciated, perhaps due to a lack of understanding of antimicrobial mechanisms, toxicity, and route of administration. Therefore, this review focuses on the efficacy, mechanism, and toxicity of omega-3 fatty acids as alternative therapeutic agents for treating and preventing diseases associated with pathogenic microorganisms.

Comparative study to develop a single method for retrieving wide class of recombinant proteins from classical inclusion bodies.

The formation of inclusion bodies (IBs) is considered as an Achilles heel of heterologous protein expression in bacterial hosts. Wide array of techniques has been developed to recover biochemically challenging proteins from IBs. However, acquiring the active state even from the same protein family was found to be an independent of single established method. Here, we present a new strategy for the recovery of wide sub-classes of recombinant protein from harsh IBs. We found that numerous methods and their combinations for reducing IB formation and producing soluble proteins were not effective, if the inclusion bodies were harsh in nature. On the other hand, different practices with mild solubilization buffers were able to solubilize IBs completely, yet the recovery of active protein requires large screening of refolding buffers. With the integration of previously reported mild solubilization techniques, we proposed an improved method, which comprised low sarkosyl concentration, ranging from 0.05 to 0.1% coupled with slow freezing (- 1 °C/min) and fast thaw (room temperature), resulting in greater solubility and the integrity of solubilized protein. Dilution method was employed with single buffer to restore activity for every sub-class of recombinant protein. Results showed that the recovered protein's activity was significantly higher compared with traditional solubilization/refolding approach. Solubilization of IBs by the described method was proved milder in nature, which restored native-like conformation of proteins within IBs.

Expression and Antitumor Function of Latcripin-4 RCC1 and ANK Domain Protein on HepG2 from the Shiitake Medicinal Mushroom, Lentinus edodes C91-3 (Agaricomycetes), Transcriptome.

The recombinant protein of Latcripin-4 regulator of chromosome condensation 1 (RCC1) and ankyrin (ANK) domains were expressed and the antitumor activity of Latcripin-4 on HepG2 cells was studied. First, the Latcripin-4 transcript was selected from the medicinal mushroom Lentinus edodes C91-3 transcriptome by bioinformatics. Then the full-length gene of Latcripin-4 was isolated with 3'-full rapid amplification of cDNA ends (RACE) and 5'-full RACE methods according to the transcriptome. The RCC1 and ANK domains from the full-length gene were selected and inserted into the expression vector pET-32a (+) and expressed in Escherichia coli Rosetta-gami (DE3). Western blotting indicated that the protein was expressed successfully. The biological function of Latcripin-4 RCC1 and ANK domain protein on HepG2 cells was studied with the CCK-8 assay. All results demonstrated that Latcripin-4 RCC1 and ANK domain protein can inhibit the growth of human HepG2 liver cancer cells, which brings new insights to identifying antitumor proteins from medicinal food for cancer therapy.

A Preclinical Evaluation of the Antitumor Activities of Edible and Medicinal Mushrooms: A Molecular Insight.

Cancer is the leading cause of morbidity and mortality around the globe. For certain types of cancer, chemotherapy drugs have been extensively used for treatment. However, severe side effects and the development of resistance are the drawbacks of these agents. Therefore, development of new agents with no or minimal side effects is of utmost importance. In this regard, natural compounds are well recognized as drugs in several human ailments, including cancer. One class of fungi, "mushrooms," contains numerous compounds that exhibit interesting biological activities, including antitumor activity. Many researchers, including our own group, are focusing on the anticancer potential of different mushrooms and the underlying molecular mechanism behind their action. The aim of this review is to discuss PI3K/AKT, Wnt-CTNNB1, and NF-κB signaling pathways, the occurrence of genetic alterations in them, the association of these aberrations with different human cancers and how different nodes of these pathways are targeted by various substances of mushroom origin. We have given evidence to propose the therapeutic attributes and possible mode of molecular actions of various mushroom-originated compounds. However, anticancer effects were typically demonstrated in in vitro and in vivo models and very limited number of studies have been conducted in the human population. It is our belief that this review will help the research community in designing concrete preclinical and clinical studies to test the anticancer potential of mushroom-originated compounds on different cancers harboring particular genetic alteration(s).

Combined effect of linolenic acid and tobramycin on Pseudomonas aeruginosa biofilm formation and quorum sensing.

Pseudomonas aeruginosa is a ubiquitous Gram negative opportunistic pathogen capable of causing severe nosocomial infections in humans, and tobramycin is currently used to treat P. aeruginosa associated lung infections. Quorum sensing regulates biofilm formation which allows the bacterium to result in fatal infections forcing clinicians to extensively use antibiotics to manage its infections leading to emerging multiple drug resistant strains. As a result, tobramycin is also becoming resistant. Despite extensive studies on drug discovery to alleviate microbial drug resistance, the continued microbial evolution has forced researchers to focus on screening various phytochemicals and dietary compounds for antimicrobial potential. Linolenic acid (LNA) is an essential fatty acid that possesses antimicrobial actions on various microorganisms. It was hypothesized that LNA may affect the formation of biofilm on P. aeruginosa and improve the potency of tobramycin. The present study demonstrated that LNA interfered with cell-to-cell communication and reduced virulence factor production. It further enhanced the potency of tobramycin and synergistically inhibited biofilm formation through P. aeruginosa quorum sensing systems. Therefore, LNA may be considered as a potential agent for adjunctive therapy and its utilization may decrease tobramycin concentration in combined treatment thereby reducing aminoglycoside adverse effects.

The potential management of oral candidiasis using anti-biofilm therapies.

Candida albicans is a minor component of the oral microbiota and an opportunistic pathogen that takes advantage of the immunocompromised host and causes oral mucositis and oral candidiasis. This organism is able to undergo phenotypic modification from a yeast to hyphae growth phase, one of the key arsenals for immune cell evasion, tissue invasion and biofilm formation. The latter property coupled with overgrowth and immune compromising factors such as HIV/AIDS, cancer treatments, organ transplantation, diabetes, corticosteroid use, dentures, and broad-spectrum antibiotic use have modified the fungus from a normal component of the microflora to a foe of an oral cavity and resulting in reduced sensitivity towards commonly utilised antifungal agents. Hence, the need for alternative therapy to curb this plight is of importance. Making use of biomolecules produced by Streptococcus mutans, application of lactoferrin which is a nonspecific host defense factor found in saliva with metal chelating and broader antimicrobial properties, use of probiotics which have the capacity to boost the host immunity through eliciting Immunoglobulin A synthesis, and perturbing the pathogen's environment via competition of space and food, and application of photodynamic therapy can help to manage the burden of oral candidiasis.

The relationship between biofilm and outer membrane vesicles: a novel therapy overview.

Microorganisms have the ability of inhabiting nearly every environment through their sophisticated mechanisms of survival such as biofilm formation and release of outer membrane vesicles (OMVs). The biofilm matrix offers microorganism protection and contributes significantly to several clinical challenges, including symptomatic inflammation, antibiotic resistance, recurrence and the spread of infectious emboli. Moreover, bacteria also have another protective mechanism of vesicle production which is used as a means of disseminating toxins to harm their host. A clear understanding of gene expression switch of bacterium from planktonic to biofilm mode offers clinical potentials in treating bacterial infections. In this respect, the treatment of bacterial infections may be achieved through (1) application of RNA interference technology to silence the expression of proteins involved in the process of biofilm formation, (2) utilization of vesicles in delivering antibiotics and (3) use of natural occurred compounds. In this review, we discuss the relationship between biofilm formation and OMV production with respect to tackling biofilm-related clinical challenges. Some prospective considerations in biofilm-associated infections treatment are also discussed.