Technique for facilitating closed reduction of difficult flexion type supracondylar humeral fracture in children.

The displaced flexion type supracondylar humeral fractures (SCHF) are inherently unstable and there is great intraoperative difficulty in obtaining and maintaining the fracture reduction by closed means. We introduced a technique for closed reduction and K-wires pinning of displaced flexion type SCHF. Fourteen patients with flexion-type SCHF (9 boys and 5 girls) underwent a reduction technique using a construct of three K-wires. The proximal wire was used for rotational control of the proximal fragment and the two distal wires were used for correction of the flexion and rotational deformity of the distal fragment. The patient's mean age was 7 (6-11) years. Results were evaluated by the anterior humeral line, Baumann's angle, carrying angle radiographically and Flynn's criteria clinically. The mean time for the union was 4.8 (4-6) weeks. The anterior humeral line passed through the middle one-third of the capitulum in 12 patients and the anterior third in two patients. The mean Baumann's angle was 19.60 ± 3.8 and the mean carrying angle was 14.21 ± 3.04. We reported no cases of failed closed reduction. The median operation time in this study was 30 (25-40) min. The mean number of C-arm images was 33.5 ± 5.23. According to Flynn's criteria; 10 cases (71.4%) were excellent and 4 (28.6%) were good. This technique can achieve the accurate reduction of flexion type SCHF and avoid the complications of both repeated closed reduction trials and open reduction. Level of Evidence: Level IV, case series.

The efficacy and adverse effects of favipiravir on patients with COVID-19: A systematic review and meta-analysis of published clinical trials and observational studies.

OBJECTIVES: This study aimed to evaluate the efficacy and adverse events of favipiravir in patients with COVID-19. METHODS: Our protocol was registered on PROSPERO (CRD42020206305). Fourteen databases were searched until February 8th, 2021. An update search for new RCTs was done on March 2nd, 2022. Meta-analysis was done for randomized controlled trials (RCTs) and non-RCTs. RESULTS: Overall, 157 studies (24 RCTs, 1 non-RCT, 21 observational studies, 2 case series, and 106 case reports) were included. On hospitalized patients, in comparison to standard of care, favipiravir showed a higher rate of viral clearance at day 5 (RR = 1.60, p = 0.02), defervescence at day 3-4 (RR = 1.99, p <0.01), chest radiological improvement (RR = 1.33, p <0.01), hospital discharge at day 10-11 (RR = 1.19, p <0.01), and shorter clinical improvement time (MD = -1.18, p = 0.05). Regarding adverse events, favipiravir groups had higher rates of hyperuricemia (RR = 9.42, p <0.01), increased alanine aminotransferase (RR = 1.35, p <0.01) but lower rates of nausea (RR = 0.42, p <0.01) and vomiting (R R= 0.19, p=0.02). There were no differences regarding mortality (RR=1.19, p=0.32), and increased aspartate aminotransferase (RR = 1.11, p = 0.25). On nonhospitalized patients, no significant differences were reported. CONCLUSIONS: Adding favipiravir to the standard of care provides better outcomes for hospitalized patients with COVID-19. Pregnant, lactating women, and patients with a history of hyperuricemia should avoid using favipiravir.

Engineering E. coli to synthesize butanol.

Biobutanol is gaining much attention as a potential biofuel due to its superior properties over ethanol. Butanol has been naturally produced via acetone-butanol-ethanol (ABE) fermentation by many Clostridium species, which are not very user-friendly bacteria. Therefore, to improve butanol titers and yield, various butanol synthesis pathways have been engineered in Escherichia coli, a much more robust and convenient host than Clostridium species. This review mainly focuses on the biosynthesis of n-butanol in engineered E. coli with an emphasis on efficient enzymes for butanol production in E. coli, butanol competing pathways, and genome engineering of E. coli for butanol production. In addition, the use of alternate strategies for butanol biosynthesis/enhancement, alternate substrates for the low cost of butanol production, and genetic improvement for butanol tolerance in E. coli have also been discussed.

A genetic toolkit for co-expression of multiple proteins of diverse physiological implication.

Construction of plasmids is crucial for expression of functional proteins of diverse physiological impact in E. coli. Here, we first designed and constructed a novel pair of bacterial expression vectors, i.e., pAS01 and pAS02, to be co-transformed with pQE30 for the co-expression of three target genes. The three plasmids contain ColE1, p15A and pSC101 origin of replication for high, medium and low copy plasmids, respectively, and same promoter (T5) and RBS. We then cloned genes encoding three reporter proteins (GFPuv, TurboRFP, and EYFP) in each of these plasmids and co-expressed in E. coli in six different combinations. Each of these reporter proteins exhibited diverse impact on growth, plasmid copy number and stability, and expression of other reporter proteins. Our results indicate that GFP and RFP were the most and the least favorable proteins for the cells, respectively, in terms of these parameters, especially on impacting expression of other co-expressed proteins.

Plant-microbe-microbe interactions influence the faba bean nodule colonization by diverse endophytic bacteria.

Legume root nodules harbor rhizobia and other non-nodulating endophytes known as nodule-associated bacteria (NAB) whose role in the legume symbiosis is still unknown. We analysed the genetic diversity of 34 NAB isolates obtained from the root nodules of faba bean grown under various soil conditions in Egypt using 16S rRNA and concatenated sequences of three housekeeping genes. All isolates were identified as members of the family Enterobacteriaceae belonging to the genera Klebsiella, Enterobacter and Raoultella. We identified nine enterobacterial genospecies, most of which have not been previously reported as NAB. All isolated strains harbored nifH gene sequences and most of them possessed plant growth-promoting (PGP) traits. Upon co-inoculation with an N2 fixing rhizobium (Rlv NGB-FR128), two strains (Enterobacter sichanensis NGB-FR97 and Klebsiella variicola NGB-FR116) significantly increased nodulation, growth and N-uptake of faba bean plants over the single treatments or the uninoculated control. The presence of these enterobacteria in nodules was significantly affected by the host plant genotype, symbiotic rhizobium genotype and endophyte genotype, indicating that the nodule colonization process is regulated by plant-microbe-microbe interactions. This study emphasizes the importance of nodule-associated enterobacteria and suggests their potential role in improving the effectiveness of rhizobial inoculants.

The impact of pyrolysis conditions on orange peel biochar physicochemical properties for sandy soil.

The citrus industry is considered one of the main contributors to agricultural waste. Peels are commonly used in the food industry or as feedstock in biorefining. In this study, the potential of waste orange peel biochar for agricultural applications in sandy soil was investigated. This will not only increase the percentage of agricultural waste recycling, but also lead to more sustainable agriculture with environmental benefits such as carbon sequestration. Biochar was produced through slow pyrolysis in the temperature range 300-600°C and at two holding durations (10 min and 60 min). Both factors had a significant impact on the physicochemical characteristics of biochar in the heating region 300-450°C. However, varying the holding time for pyrolysis temperatures beyond 450°C had a diminishing effect on biochar properties compared with the impact of increasing pyrolysis temperature. The study also looked at certain properties that are specific to agricultural application not previously reported for orange peel. Very high cation exchange capacities of 70 cmol kg-1 were achieved at 300°C, whereas water holding capacity was not strongly influenced by pyrolysis conditions. Preliminary planting tests indicate potential for improving agricultural sustainability in sandy soils. The technoeconomic analysis of biochar showed that the pyrolysis process can be profitable with sufficient plant capacity.

Improved Butanol Production Using FASII Pathway in E. coli.

n-Butanol is often considered a potential substitute for gasoline due to its physicochemical properties being closely related to those of gasoline. In this study, we extend our earlier work to convert endogenously producing butyrate via the FASII pathway using thioesterase TesBT to its corresponding alcohol, i.e., butanol. We first assembled pathway genes, i.e., car encoding carboxylic acid reductase from Mycobacterium marinum, sfp encoding phosphopantetheinyl transferase from Bacillus subtilis, and adh2 encoding alcohol dehydrogenase from S. cerevisiae, responsible for bioconversion of butyrate to butanol in three different configurations (Operon, Pseudo-Operon, and Monocistronic) to achieve optimum expression of each gene and compared with the clostridial solventogenic pathway for in vivo conversion of butyrate to butanol under aerobic conditions. An E. coli strain harboring car, sfp, and adh2 in pseudo-operon configuration was able to convert butyrate to butanol with 100% bioconversion efficiency when supplemented with 1 g/L of butyrate. Further, co-cultivation of an upstream strain (butyrate-producing) with a downstream strain (butyrate to butanol converting) at different inoculation ratios was investigated, and an optimized ratio of 1:4 (upstream strain: downstream strain) was found to produce ∼2 g/L butanol under fed-batch fermentation. Further, a mono-cultivation approach was applied by transforming a plasmid harboring tesBT gene into the downstream strain. This approach produced 0.42 g/L in a test tube and ∼2.9 g/L butanol under fed-batch fermentation. This is the first report where both mono- and co-cultivation approaches were tested and compared for butanol production, and butanol titers achieved using both strategies are the highest reported values in recombinant E. coli utilizing FASII pathway.

Food waste from a university campus in the Middle East: Drivers, composition, and resource recovery potential.

Food waste is a pressing issue that imposes economic, social and environmental impacts on both developing and developed countries. This study analyzes quantitatively and qualitatively the generated food waste at various food outlets of a university campus in Qatar. It is a fundamental step to manage the issue of food waste from educational institutes. The investigation comprised four stages: screening, sampling, surveying, and synthesis. Food waste generation at the sampled locations was estimated at 329.5 kg/day or 80 t/year. Based on per sales estimates, total food waste was 980 g/sale and 757 g/sale at the student male and female housing complexes, respectively, equating to roughly one wasted meal for each sold meal. The majority of this waste was avoidable waste and the root cause for the excessive food waste generation was overproduction rather than consumer wastage. The study found that the main food provider, who primarily serves buffet style meals, lacks the proper tools to measure food waste generated at their cafeterias. Past experience was the primary tool to support the company's demand management estimation which has proven unsuccessful and highlights the need to not only educate the consumer but also food providers. Possible treatments routes are discussed based on food waste characterization findings.

CRISPR/Cas9-mediated engineering of Escherichia coli for n-butanol production from xylose in defined medium.

Butanol production from agricultural residues is the most promising alternative for fossil fuels. To reach the economic viability of biobutanol production, both glucose and xylose should be utilized and converted into butanol. Here, we engineered a dual-operon-based synthetic pathway in the genome of E. coli MG1655 to produce n-butanol using CRISPR/Cas9 technology. Further deletion of competing pathway followed by fed-batch cultivation of the engineered strain in a bioreactor with glucose-containing complex medium yielded 5.4 g/L n-butanol along with pyruvate as major co-product, indicating a redox imbalance. To ferment xylose into butanol in redox-balanced manner, we selected SSK42, an ethanologenic E. coli strain engineered and evolved in our laboratory to produce ethanol from xylose, for integrating synthetic butanol cassette in its genome via CRISPR/Cas9 after deleting the gene responsible for endogenous ethanol production. The engineered plasmid- and marker-free strain, ASA02, produced 4.32 g/L butanol in fed-batch fermentation in completely defined AM1-xylose medium.

Boosting isoprene production via heterologous expression of the Kudzu isoprene synthase gene (kIspS) into Bacillus spp. cell factory.

Isoprene represents a key building block for the production of valuable materials such as latex, synthetic rubber or pharmaceutical precursors and serves as basis for advanced biofuel production. To enhance the production of the volatile natural hydrocarbon isoprene, released by plants, animals and bacteria, the Kudzu isoprene synthase (kIspS) gene has been heterologously expressed in Bacillus subtilis DSM 402 and Bacillus licheniformis DSM 13 using the pHT01 vector. As control, the heterologous expression of KIspS in E. coli BL21 (DE3) with the pET28b vector was used. Isoprene production was analyzed using Gas Chromatography Flame Ionization Detector. The highest isoprene production was observed by recombinant B. subtilis harboring the pHT01-kIspS plasmid which produced 1434.3 µg/L (1275 µg/L/OD) isoprene. This is threefold higher than the wild type which produced 388 µg/L (370 µg/L/OD) isoprene, when both incubated at 30 °C for 48 h and induced with 0.1 mM IPTG. Additionally, recombinant B. subtilis produced fivefold higher than the recombinant B. licheniformis, which produced 437.2 µg/L (249 µg/L/OD) isoprene when incubated at 37 °C for 48 h induced with 0.1 mM IPTG. This is the first report of optimized isoprene production in B. licheniformis. However, recombinant B. licheniformis showed less isoprene production. Therefore, recombinant B. subtilis is considered as a versatile host for heterologous production of isoprene.

Genetic improvement of n-butanol tolerance in Escherichia coli by heterologous overexpression of groESL operon from Clostridium acetobutylicum.

Strain tolerance to toxic metabolites remains an important issue in the production of biofuels. Here we examined the impact of overexpressing the heterologous groESL chaperone from Clostridium acetobutylicum to enhance the tolerance of Escherichia coli against several stressors. Strain tolerance was identified using strain maximum specific growth rate (µ) and strain growth after a period of solvent exposure. In comparison with control strain, the groESL overexpressing strain yielded a 27 % increase in growth under 0.8 % (v/v) butanol, a 9 % increase under 1 % (v/v) butanol, and a 64 % increase under 1.75 (g/l) acetate. Moreover, after 10 h, groESL overexpression resulted in increase in relative tolerance of 58 % compared with control strain under 0.8 % (v/v) butanol, 56 % increase under 1 % (v/v) butanol, 42 % increase under 1 % (v/v) isobutanol, 36 % increase under 4 % (v/v) ethanol, 58 % increase under 1.75 (g/l) acetate. These data demonstrate that overexpression of the groESL from C. acetobutylicum in E. coli increased tolerance to several stressors. Solvent tolerant strain of E. coli was developed to be used as a basic strain for biofuel production.

Genetic determinants for n-butanol tolerance in evolved Escherichia coli mutants: cross adaptation and antagonistic pleiotropy between n-butanol and other stressors.

Cross-tolerance and antagonistic pleiotropy have been observed between different complex phenotypes in microbial systems. These relationships between adaptive landscapes are important for the design of industrially relevant strains, which are generally subjected to multiple stressors. In our previous work, we evolved Escherichia coli for enhanced tolerance to the biofuel n-butanol and discovered a molecular mechanism of n-butanol tolerance that also conferred tolerance to the cationic antimicrobial peptide polymyxin B in one specific lineage (green fluorescent protein [GFP] labeled) in the evolved population. In this work, we aim to identify additional mechanisms of n-butanol tolerance in an independent lineage (yellow fluorescent protein [YFP] labeled) from the same evolved population and to further explore potential cross-tolerance and antagonistic pleiotropy between n-butanol tolerance and other industrially relevant stressors. Analysis of the transcriptome data of the YFP-labeled mutants allowed us to discover additional membrane-related and osmotic stress-related genes that confer n-butanol tolerance in E. coli. Interestingly, the n-butanol resistance mechanisms conferred by the membrane-related genes appear to be specific to n-butanol and are in many cases antagonistic with isobutanol and ethanol. Furthermore, the YFP-labeled mutants showed cross-tolerance between n-butanol and osmotic stress, while the GFP-labeled mutants showed antagonistic pleiotropy between n-butanol and osmotic stress tolerance.