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2036-7481, 2036-7473

2021 ◽  
Vol 13 (1) ◽  
pp. 38-48
Author(s):  
Cátia Marques ◽  
Adriana Belas ◽  
Juliana Menezes ◽  
Joana Moreira da Silva ◽  
Patrícia Cavaco-Silva ◽  
...  

Proteus mirabilis is an important pathogen that is associated with urinary tract infections. This study aims to determine the colonization and sharing of P. mirabilis between healthy companion animals and humans that are living together and to evaluate the clonal relatedness of the fecal and clinical stains. Eighteen households (24 humans, 18 dogs, 8 cats) with at least one human–animal pair were studied. Fecal samples were plated onto MacConkey and Hektoen agar and P. mirabilis PFGE analysis (NotI; Dice/UPGMA; 1.5% tolerance) was conducted for the households with multiple positive participants. Antimicrobial-resistance was tested according to CLSI. The fecal P. mirabilis pulse-types were compared with uropathogenic clinical strains (n = 183). Forty-nine P. mirabilis were isolated from eight households. The percentage of colonization in the dogs (44.4%, n = 8/18) was significantly higher (p = 0.0329) than in the humans (12.5%, n = 3/24). Three households had multiple colonized participants. One human–dog pair shared related P. mirabilis strains, which clustered with a clinical strain of animal origin (82.5%). One fecal P. mirabilis strain, from a dog, clustered with two human community-acquired clinical strains (80.9%, 88.9%). To our knowledge, this is the first report of dogs and humans living in close contact and sharing related P. mirabilis strains. The high frequency of colonization in the dogs underlines their possible role as P. mirabilis reservoirs for humans and other dogs.


2021 ◽  
Vol 13 (1) ◽  
pp. 14-37
Author(s):  
Carina Silva ◽  
Sara Sá ◽  
Carla Guedes ◽  
Carla Oliveira ◽  
Cláudio Lima ◽  
...  

The Pseudomonas aeruginosa is one of the bacteria that cause serious infections due to resistance to many antibiotics can be fatal in severe cases. Antimicrobial resistance is a global public health concern. To solve this problem, interest in phage therapy has revived; some studies are being developed to try to prove the effectiveness of this therapy. Thus, in this opinion article, several historical aspects are addressed as well some applications of phage therapy against P. aeruginosa.


2021 ◽  
Vol 13 (1) ◽  
pp. 1-13
Author(s):  
Hee Young Cho ◽  
Sung Shin Shim ◽  
Hee Jin Park ◽  
Dong Hyun Cha

Preterm birth (PTB) is a global health issue and one of the most challenging problems affecting 12.9 million births worldwide. PTB is a multi-etiological disease and remains incompletely understood. The major cause of PTB is infection or inflammation and disruption of the vaginal microbiome, which affects the maternal immunologic response leading to PTB. The vaginal microbiome composition changes by a shift in the community are typically dominated by Lactobacillus during pregnancy. There are complex interactions between the maternal microbiome in pregnancy and the development of PTB, therefore, researchers have struggled to connect the maternal microbiome with the dysregulation of the maternal immune response in cases of PTB. The host microbiome affects alterations of the microorganisms with external stimuli such as disease, nutrition, immunity, and behavior. In this review, we discuss the complex association between the maternal microbiome and the risk of PTB and also focus on recent aspects of the prevention of PTB.


2021 ◽  
Vol 12 (4) ◽  
pp. 967-977
Author(s):  
Ntombikhona F. Maphumulo ◽  
Michelle L. Gordon

An increasing number of patients in Africa are experiencing virological failure on a second-line antiretroviral protease inhibitor (PI)-containing regimen, even without resistance-associated mutations in the protease region, suggesting a potential role of other genes in PI resistance. Here, we investigated the prevalence of mutations associated with Lopinavir/Ritonavir (LPV/r) failure in the Envelope gene and the possible coevolution with mutations within the Gag-protease (gag-PR) region. Env and Gag-PR sequences generated from 24 HIV-1 subtype C infected patients failing an LPV/r inclusive treatment regimen and 344 subtype C drug-naïve isolates downloaded from the Los Alamos Database were analyzed. Fisher’s exact test was used to determine the differences in mutation frequency. Bayesian network probability was applied to determine the relationship between mutations occurring within the env and gag-PR regions and LPV/r treatment. Thirty-five mutations in the env region had significantly higher frequencies in LPV/r-treated patients. A combination of Env and Gag-PR mutations was associated with a potential pathway to LPV/r resistance. While Env mutations were not directly associated with LPV/r resistance, they may exert pressure through the Gag and minor PR mutation pathways. Further investigations using site-directed mutagenesis are needed to determine the impact of Env mutations alone and in combination with Gag-PR mutations on viral fitness and LPV/r efficacy.


2021 ◽  
Vol 12 (4) ◽  
pp. 950-966
Author(s):  
Phakamani H. Tsilo ◽  
Albertus K. Basson ◽  
Zuzingcebo G. Ntombela ◽  
Tsolanku S. Maliehe ◽  
Rajasekhar V. S. R. Pullabhotla

Biolocculants are gaining attention in research due to their environmental friendliness and innocuousness to human in comparison to the conventional flocculants. The present study aimed to investigate the ability of fungi from Kombucha tea SCOBY to produce effective bioflocculant in bulk. A 16S rRNA gene sequence analysis was utilized to identify the isolate. The medium composition (carbon and nitrogen sources) and culture conditions (inoculum size, temperature, shaking speed, pH, and time) were optimized using one-factor-at-a-time method. The functional groups, morphology, and crystallinity of the bioflocculant were evaluated using Fourier transform infrared (FT-IR), scan electron microscope (SEM) and X-ray diffractometry (XRD). The fungus was found to be Pichia kudriavzevii MH545928.1. It produced a bioflocculant with flocculating activity of 99.1% under optimum conditions; 1% (v/v) inoculum size, glucose and peptone as nutrient sources, 35 °C, pH 7 and the shaking speed of 140 rpm for 60 h. A cumulus-like structure was revealed by SEM; FT-IR displayed the presence of hydroxyl, carboxyl, amine, and thiocynates. The XRD analysis demonstrated the bioflocculant to have big particles with diffraction peaks at 10° and 40° indicating its crystallinity. Based on the obtained results, P. kudriavzevii MH545928.1 has potential industrial applicability as a bioflocculant producer.


2021 ◽  
Vol 12 (4) ◽  
pp. 938-949
Author(s):  
Joanna Klepacka ◽  
Zuzanna Zakrzewska ◽  
Małgorzata Czogała ◽  
Adriana Chromy-Czoniszwili ◽  
Szymon Skoczeń ◽  
...  

The worldwide surge of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic and led governments to control spread of the virus and provide care for the population affected by the infection. Although, in children, COVID-19 is usually asymptomatic or mild (except PIMS), the pandemic affected the whole socioeconomic system and led to the overwhelming of healthcare facilities. We report retrospective observations of the prevalence of various infectious diseases during the SARS-CoV-2 pandemic in a tertiary multidisciplinary pediatric center in Southern Poland. We retrospectively evaluated the impact of the SARS-CoV-2 pandemic on the number of other infections diagnosed in a pediatric tertiary care referral center. Our analysis included the period from the beginning of February to the end of April 2020 (spring pandemic wave), and from the beginning of September to the end of November 2020 (autumn pandemic wave). We compared them to the appropriate periods of 2019. The evaluation included blood, urine, stool and lover respiratory tract cultures as well as virological investigations. Additionally, the costs of antibiotics and antifungal drugs in selected departments were assessed. Our analysis showed considerable reduction in the majority of common infections except for influenza A and B. The microbiological data correspond with economical summary of antibiotic costs, which were significantly lower during the pandemic. One exception was the number of positive blood cultures, which increased even though the overall number of tests was lower. A general reduction of the number of infections diagnosed in children could result from the implemented preventative measures associated with the pandemic and the generally increased awareness of the risk of infection among parents and guardians. The treatment of the most serious diseases continued as it did before the pandemic. To our knowledge, this study is the first attempt to assess the impact of the COVID-19 pandemic on the prevalence of infections in a large pediatric center. Further research on the impact of the COVID-19 pandemic on the healthcare systems is necessary.


2021 ◽  
Vol 12 (4) ◽  
pp. 916-937
Author(s):  
Gabriele Meroni ◽  
Simona Panelli ◽  
Gianvincenzo Zuccotti ◽  
Claudio Bandi ◽  
Lorenzo Drago ◽  
...  

Bacterial populations inhabiting a variety of natural and human-associated niches have the ability to grow in the form of biofilms. A large part of pathological chronic conditions, and essentially all the bacterial infections associated with implanted medical devices or prosthetics, are caused by microorganisms embedded in a matrix made of polysaccharides, proteins, and nucleic acids. Biofilm infections are generally characterized by a slow onset, mild symptoms, tendency to chronicity, and refractory response to antibiotic therapy. Even though the molecular mechanisms responsible for resistance to antimicrobial agents and host defenses have been deeply clarified, effective means to fight biofilms are still required. Lactic acid bacteria (LAB), used as probiotics, are emerging as powerful weapons to prevent adhesion, biofilm formation, and control overgrowth of pathogens. Hence, using probiotics or their metabolites to quench and interrupt bacterial communication and aggregation, and to interfere with biofilm formation and stability, might represent a new frontier in clinical microbiology and a valid alternative to antibiotic therapies. This review summarizes the current knowledge on the experimental and therapeutic applications of LAB to interfere with biofilm formation or disrupt the stability of pathogenic biofilms.


2021 ◽  
Vol 12 (4) ◽  
pp. 907-915
Author(s):  
Adriana Belas ◽  
Joana Correia ◽  
Cátia Marques ◽  
Luís Telo da Gama ◽  
Constança Pomba

The purpose of this study was to evaluate the presence and load of ESBL/AmpC-producing Enterobacteriaceae fecal carriage in healthy dogs. Fecal samples were collected from dogs submitted to surgical procedures (n = 25). Fecal samples were collected before surgery (BS) and after surgery (AS). β-lactamases were detected by PCR. Statistical analyses were performed with SAS software (v.9.4); a p value ≤ 0.05 was considered statistically significant. The ESBL/AmpC-producing Enterobacteriaceae bacteria species detected in this study were E. coli, K. pneumoniae and E. cloacae. TEM, and CTX-M-1 group genes were the most frequent β-lactamases detected. The number of dogs colonized with 3GC-resistant Enterobacteriaceae bacteria was significantly higher in the AS (63.6%, n = 14/22) group compared to in the BS group (20.0%, n = 5/25, p = 0.0033). The ESBL/AmpC-producing bacteria fecal load was significantly higher in the AS group compared to in the BS (p = 0.025) group. This study shows that 3GC-resistant Enterobacteriaceae and ESBLs/AmpC producers in the veterinary clinical practice are a concern and highlights the need to implement preventive measures to minimize their spread.


2021 ◽  
Vol 12 (4) ◽  
pp. 899-906
Author(s):  
Emmanuel Edwar Siddig ◽  
Ayman Ahmed ◽  
Yousif Ali ◽  
Sahar Mubarak Bakhiet ◽  
Nouh Saad Mohamed ◽  
...  

Mycetoma is a neglected tropical disease that is associated with poor communities and socioeconomically impaired individuals in the tropical and sub-tropical areas. Interestingly, the disease is caused by either bacteria (actinomycetoma) or fungus (eumycetoma). The latter form of the disease, eumycetoma, is the most common type in Africa. Eumycetoma is characterized by a prolonged disease duration and low cure rate. The effective case management of eumycetoma largely depends on the accurate diagnosis and identification of the causative agent to the species level and evaluating its susceptibility to the available drugs. This review summarizes the currently available and used antifungal agents for the treatment of eumycetoma and discusses optimizing the newly developed antifungals as a potential second line for eumycetoma treatment.


2021 ◽  
Vol 12 (4) ◽  
pp. 888-898
Author(s):  
Mariana Fernandez ◽  
Arlene Garcia ◽  
David A. Vargas ◽  
Alexandra Calle

The shedding of foodborne pathogenic bacteria by food-animals can be affected by multiple factors, such as animal health, diet, stress, and environmental conditions. The practices that come with transport involve fasting, handling, mixing with unfamiliar pigs, and fluctuating temperatures. These practices, especially fasting and transport, can increase the microbial load in the feces of animals. The use of alginate hydrogels is a novel delivery system that can be a potential food safety intervention during transport to induce satiety and provide electrolytes to the animal’s system. This study sought to observe microbial shedding as affected by fasting and hydrogel bead supplementation during transport. Sixty market pigs were subjected to a 12 h fasting period and an additional 4 h transport period, in which a treatment group was fed hydrogel beads and a control group was not. Sampling points were before fast (BF), before transport (BT), and after transport (AT). Fecal samples were collected from every animal at each sampling point. Results from this study showed a significant increase in the concentrations of both Enterobacteriaceae and Escherichia coli between the before fast (BF) and after transport (AT) sampling points. However, no difference (p > 0.05) was found between the treatment (hydrogel) and control (no hydrogel) during transport. Moreover, no significant difference was found in the prevalence of Salmonella and E. coli O157:H7 at the three different sampling points, or between the treatment and control groups.


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