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1.
Viruses ; 16(3)2024 03 05.
Article in English | MEDLINE | ID: mdl-38543769

ABSTRACT

Severe acute respiratory tract infections (SARIs) has been well described in South Africa with seasonal patterns described for influenza and respiratory syncytial virus (RSV), while others occur year-round (rhinovirus and adenovirus). This prospective syndromic hospital-based surveillance study describes the prevalence and impact of public interventions on the seasonality of other respiratory pathogens during the coronavirus disease-19 (COVID-19) pandemic. This occurred from August 2018 to April 2022, with 2595 patients who met the SARS case definition and 442 controls, from three sentinel urban and rural hospital sites in South Africa. Naso/oro-pharyngeal (NP/OP) swabs were tested using the FastTrack Diagnostics® Respiratory pathogens 33 (RUO) kit. Descriptive statistics, odds ratios, and univariate/multivariate analyses were used. Rhinovirus (14.80%, 228/1540) and Streptococcus pneumoniae (28.50%, 439/1540) were most frequently detected in NP/OP swabs and in children <1 years old (35%, 648/1876). Among others, pathogens associated with SARI cases causing disease were influenza A&B, HRV, RSV, hCoV 229e, Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae. Pre-COVID-19, seasonal trends of these pathogens correlated with previous years, with RSV and influenza A seasons only resuming after the national lockdown (2021). It is evident that stringent lockdown conditions have severe impacts on the prevalence of respiratory tract infections.


Subject(s)
COVID-19 , Enterovirus Infections , Influenza, Human , Respiratory Syncytial Virus, Human , Respiratory Tract Infections , Child , Humans , Infant , Influenza, Human/epidemiology , South Africa/epidemiology , Prevalence , Prospective Studies , Respiratory Tract Infections/epidemiology , Streptococcus pneumoniae , Rhinovirus , COVID-19/epidemiology
2.
Bioprocess Biosyst Eng ; 47(3): 313-323, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38438572

ABSTRACT

Molecular docking is an important computational analysis widely used to predict the interaction of enzymes with several starting materials for developing new valuable products from several starting materials, including oils and fats. In the present study, molecular docking was used as an efficient in silico screening tool to select biocatalysts with the highest catalytic performance in butyl esters production in a solvent-free system, an eco-friendly approach, via direct esterification of free fatty acids from Licuri oil with butanol. For such purpose, three commercial lipase preparations were used to perform molecular docking studies such as Burkholderia cepacia (BCL), Porcine pancreatic (PPL), and Candida rugosa (CRL). Concurrently, the results obtained in BCL and CRL are the most efficient in the esterification process due to their higher preference for catalyzing the esterification of lauric acid, the main fatty acid found in the licuri oil composition. Meanwhile, PPL was the least efficient because it preferentially interacts with minor fatty acids. Molecular docking with the experimental results indicated the better performance in the synthesis of esters was BCL. In conclusion, experimental results analysis shows higher enzymatic productivity in esterification reactions of 1294.83 µmol/h.mg, while the CRL and PPL demonstrated the lowest performance (189.87 µmol / h.mg and 23.96 µmol / h.mg, respectively). Thus, molecular docking and experimental results indicate that BCL is a more efficient lipase to produce fatty acids and esters from licuri oil with a high content of lauric acid. In addition, this study also demonstrates the application of molecular docking as an important tool for lipase screening to achieve more sustainable production of butyl esters with a view synthesis of biolubricants.


Subject(s)
Fatty Acids , Lipase , Animals , Swine , Lipase/chemistry , Molecular Docking Simulation , Catalytic Domain , Fatty Acids/chemistry , Esterification , Esters , Lauric Acids , Enzymes, Immobilized/metabolism
3.
Biotechnol Lett ; 46(1): 85-95, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38064041

ABSTRACT

The objective of this study was to obtain sufficient information on the thermal stabilization of a food-grade lipase from Thermomyces lanuginosus (TLL) using the immobilization technique. To do this, a new non-porous support was prepared via the sequential extraction of SiO2 from rice husks, followed by functionalization with (3-aminopropyl) triethoxysilane - 3-APTES (Amino-SiO2), and activation with glutaraldehyde - GA (GA-Amino-SiO2). We evaluated the influence of GA concentration, which varied from 0.25% v v-1 to 4% v v-1, on the immobilization parameters and enzyme thermal stabilization. The thermal inactivation parameters for both biocatalyst forms (soluble or immobilized TLL) were calculated by fitting a non-first-order enzyme inactivation kinetic model to the experimental data. According to the results, TLL was fully immobilized on the external support surface activated with different GA concentrations using an initial protein load of 5 mg g-1. A sharp decrease of hydrolytic activity was observed from 216.6 ± 12.4 U g-1 to 28.6 ± 0.9 U g-1 of after increasing the GA concentration from 0.25% v v-1 to 4.0% v v-1. The support that was prepared using a GA concentration at 0.5% v v-1 provided the highest stabilization of TLL - 31.6-times more stable than its soluble form at 60 °C. The estimations of the thermodynamic parameters, e.g., inactivation energy (Ed), enthalpy (ΔH#), entropy (ΔS#), and the Gibbs energy (ΔG#) values, confirmed the enzyme stabilization on the external support surface at temperatures ranging from 50 to 65 °C. These results show promising applications for this new heterogeneous biocatalyst in industrial processes given the high catalytic activity and thermal stability.


Subject(s)
Lipase , Oryza , Propylamines , Silanes , Lipase/metabolism , Silicon Dioxide , Glutaral , Enzymes, Immobilized/metabolism , Thermodynamics , Enzyme Stability
4.
Viruses ; 15(11)2023 Nov 02.
Article in English | MEDLINE | ID: mdl-38005884

ABSTRACT

West Nile virus (WNV), a mosquito-borne flavivirus, is endemic to South Africa. However, its contribution to acute febrile and neurological disease in hospitalized patients in South Africa is unknown. This study examined two patient cohorts for WNV using molecular testing and IgM serology with confirmation of serological results by viral neutralization tests (VNT) to address this knowledge gap. Univariate analysis was performed using collected demographic and clinical information to identify risk factors. In the first cohort, 219 cerebrospinal fluid (CSF) specimens from patients with acute neurological disease in Gauteng hospitals collected in January to June 2017 were tested for WNV. The study identified WNV in 8/219 (3.65%, 95.00% CI (1.59-7.07)) patients with unsolved neurological infections. The second cohort, from 2019 to 2021, included 441 patients enrolled between January and June with acute febrile or neurological disease from urban and rural sites in Gauteng and Mpumalanga provinces. West Nile virus was diagnosed in 40/441 (9.07%, 95.00% CI (6.73-12.12)) of patients, of which 29/40 (72.50%, 95.00% CI (56.11-85.40)) had neurological signs, including headaches, encephalitis, meningitis, and acute flaccid paralysis (AFP). Notably, most of the cases were identified in children although adolescents and senior adults had a significantly higher risk of testing WNV positive. This suggests a previously underestimated disease burden and that WNV might be underrecognized as a cause of febrile and neurological diseases in hospitalized patients in South Africa, especially in children. This emphasizes the importance of further research and awareness regarding arboviruses of public health concern.


Subject(s)
Fever of Unknown Origin , Flavivirus , West Nile Fever , West Nile virus , Adult , Child , Adolescent , Animals , Humans , West Nile Fever/diagnosis , West Nile Fever/epidemiology , South Africa/epidemiology , Antibodies, Viral
5.
Zygote ; 31(6): 582-587, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37955189

ABSTRACT

Traditionally, in vitro oocyte and embryo culture progresses through a series of varying culture medium. To investigate simplifying the in vitro production of bovine cumulus-oocyte complexes (COCs), this study used synthetic oviductal fluid (SOF) supplemented with conjugated linoleic acid (CLA). Special interest was placed on gene expression linked to lipid metabolism and oocyte maturation. COCs were matured in different media: Medium 199 (M199 group), M199 with 100 µM CLA (M199 + CLA group), SOF (SOF group), and SOF with 100 µM CLA (SOF + CLA group). COCs matured with SOF showed a higher relative abundance of mRNA of quality indicators gremlin 1 (GREM1) and prostaglandin-endoperoxide synthase 2 (PTGS2) in oocytes, and GREM1 in cumulus cells compared with in the M199 group. SOF medium COCs had a higher relative abundance of fatty acid desaturase 2 (FADS2) compared with the M199 group, which is essential for lipid metabolism in oocytes. Furthermore, the abundance of stearoyl-coenzyme A desaturase 1 (SCD1) in oocytes matured with SOF was not influenced by the addition of CLA, whereas the relative abundance of SCD1 was reduced in M199 medium with CLA. We concluded that maturation in SOF medium results in a greater abundance of genes linked to quality and lipidic metabolism in oocytes, regardless of the addition of CLA.


Subject(s)
Fertilization in Vitro , Lipid Metabolism , Female , Animals , Cattle , Lipid Metabolism/genetics , Oocytes/metabolism , Oogenesis , Culture Media/pharmacology , Culture Media/metabolism , Gene Expression , In Vitro Oocyte Maturation Techniques/methods
6.
Pathogens ; 12(9)2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37764908

ABSTRACT

Viruses in the Orthobunyavirus genus, Peribunyaviridae family, are associated with encephalitis, birth defects and fatalities in animals, and some are zoonotic. Molecular diagnostic investigations of animals with neurological signs previously identified Shuni virus (SHUV) as the most significant orthobunyavirus in South Africa (SA). To determine if other orthobunyaviruses occur in SA, we screened clinical specimens from animals with neurological signs, abortions, and acute deaths from across SA in 2021 using a small (S) segment Simbu serogroup specific TaqMan real-time reverse transcription polymerase chain reaction (RT-PCR). Positive cases were subjected to Sanger sequencing and phylogenetic analysis to identify specific viruses involved, followed by next-generation sequencing (NGS) and additional PCR assays targeting the medium (M) segment and the large (L) segment. In total, 3/172 (1.7%) animals were PCR positive for Simbu serogroup viruses, including two horses with neurological signs and one aborted goat fetus in 2021. Phylogenetic analyses confirmed that the two horses were infected with SHUV strains with nucleotide pairwise (p-) distances of 98.1% and 97.6% to previously identified strains, while the aborted goat fetus was infected with a virus closely related to Shamonda virus (SHAV) with nucleotide p-distances between 94.7% and 91.8%. Virus isolation was unsuccessful, likely due to low levels of infectious particles. However, phylogenetic analyses of a larger fragment of the S segment obtained through NGS and partial sequences of the M and L segments obtained through RT-PCR and Sanger sequencing confirmed that the virus is likely SHAV with nucleotide p-distances between 96.6% and 97.8%. This is the first detection of SHAV in an aborted animal in SA and suggests that SHAV should be considered in differential diagnosis for abortion in animals in Southern Africa.

7.
Global Spine J ; : 21925682231194453, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37585445

ABSTRACT

STUDY DESIGN: A primary, observational, cross-sectional, analytical study. OBJECTIVE: The development of a framework for systematic telemedicine (TM) for orthopedic physicians in frequent clinical care may increase agreement in diagnosis and satisfaction among users of TM. Therefore, this study aimed to estimate the agreement in the diagnosis of low back pain (LBP) between TM, systematized by a self-completed digital questionnaire, and face-to-face (FF) care in patients with LBP. METHODS: This study included adults up to 75 years of age with LBP for more than 6 weeks. They were evaluated at 2 independent time points (TM and FF) by different orthopedists with 3 different levels of expertise. Professionals evaluated the sample without prior knowledge of the diagnosis, and each orthopedist provided a diagnosis. Diagnostic agreement was the primary outcome. Secondary outcomes were the duration of the visit and satisfaction among healthcare professionals. RESULTS: A total of 168 participants were eligible, of whom 126 sought care through TM and 122 sought FF care (mean age, 47 years [range, 18-75 years]; 66.4% women). The agreement among professionals regarding the diagnosis was moderate (kappa = .585, P = .001). TM was faster than FF (11.9 minutes (standard deviation = 4.1) vs 18.6 (SD = 6.9), P < .001). Professional satisfaction was higher among spine specialists than among orthopedic residents and orthopedists who were not specialists in spine surgery. CONCLUSION: Agreement in diagnosis was moderate for TM, with a 30% shorter visit duration than FF. Satisfaction varied by professional expertise and was higher among spine specialists than among professionals with other expertise.

8.
Theriogenology ; 206: 87-95, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37201299

ABSTRACT

Early embryonic mortality caused by maternal-fetal recognition failure in the three weeks after fertilization represents a major cause of reproductive inefficiency in the cattle industry. Modifying the amounts and ratios of prostaglandin (PG) F2α and PGE2 can benefit the establishment of pregnancy in cattle. Adding conjugated linoleic acid (CLA) to endometrial and fetal cells culture affects PG synthesis, but its effect on bovine trophoblast cells (CT-1) is unknown. The aim of this study was to determine the effects of CLA (a mixture of cis- and trans-9, 11- and -10,12-octadecadienoic acids) on PGE2 and PGF2α synthesis and the expression of transcripts involved with maternal-fetal recognition of bovine trophectoderm. Cultures of CT-1 were exposed to CLA for 24, 48 and 72 h. Transcript abundance was determined by qRT-PCR and hormone profiles were quantified by ELISA. The PGE2 and PGF2α concentrations were reduced in the culture medium of CLA-exposed CT-1 compared to that of unexposed cells. Furthermore, CLA supplementation increased the PGE2:PGF2α ratio in CT-1 and had a quadratic effect (P < 0.05) on the relative expression of MMP9, PTGES2, and PTGER4. The relative expression levels of PTGER4 were reduced (P < 0.05) in CT-1 cultured with 100 µM CLA than in the unsupplemented and 10 µM-CLA groups. Treatment of CT-1 with CLA decreased PGE2 and PGF2α synthesis but a biphasic effect of CLA was observed on the PGE2:PGF2α ratio and relative abundance of transcripts with 10 µM CLA providing maximal improvements in each endpoint. Our data suggest that CLA may influence eicosanoid metabolic process and extracellular matrix remodeling.


Subject(s)
Linoleic Acids, Conjugated , Prostaglandins , Pregnancy , Female , Cattle , Animals , Linoleic Acids, Conjugated/pharmacology , Dinoprost/pharmacology , Dinoprost/metabolism , Trophoblasts/metabolism , Dinoprostone/metabolism , Dietary Supplements
9.
Food Sci Biotechnol ; 32(5): 689-696, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37009043

ABSTRACT

This study aims at the synthesis of hexyl butyrate by Candida rugosa lipase (CRL) immobilized on Diaion HP 20. The lipase load used was 28.7 ± 2.1 mg/g (mg of lipase/g of support), whose hydrolytic activity was 132.0 ± 2.5 U/g. To obtain the maximum production of hexyl butyrate, the Box-Behnken design statistical planning was used, having as independent variables; biocatalyst concentration, temperature and acid:alcohol molar ratio and ester conversion as a dependent variable at 60, 180 and 480 min. For 60 min, 90.8% conversion was obtained at 47.25 ºC, 1:1.4 molar ratio and 17.65% of biocatalyst; 180 min, 94.5% conversion at 59.5 ºC, 1:2 molar ratio and 15.8% biocatalyst; 480 min, 95.01% conversion at 47.0 ºC, 1:2 molar ratio and 16.9% biocatalyst. CRL-Diaion HP 20 retained 60% of its initial activity after ten cycles of reactions showing potential for industrial use. The ester produced was identified by gas chromatography analyses. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01200-1.

10.
Acta Ortop Bras ; 31(spe1): e255572, 2023.
Article in English | MEDLINE | ID: mdl-37082161

ABSTRACT

Objectives: This study aimed to evaluate the functional results of the treatment protocol for the treatment of transolecranon fracture-dislocation, by surgical reduction and osteosynthesis with plate and screws, in patients attended at a referral hospital for orthopedic trauma, with a minimum follow-up period of six months. Methods: Twenty-five individuals treated surgically from January 2014 to November 2018 were selected for a primary observational longitudinal study using questionnaires to assess upper limb and elbow function (DASH and MEPS), quality of life (SF-12), pain (visual analog scale - VAS), and radiographic evaluation in anteroposterior and lateral views of the elbow. Results: Fifteen patients were male, and the mean age was 46.8 years. All participants had their fractures consolidated, with no radiolgraphic signs of implant failure, or degenerative arthritis. Mean range of motion was reduced relative to the contralateral limb: 102.6º for flexion-extension and 132.8º for pronation-supination. The mean MEPS and DASH scores were 89.6 and 16.5 respectively. There was no residual pain in 84% of the cases according to the VAS. Conclusion: The surgical treatment proposed for transolecranon fracture-dislocations showed satisfactory results according to MEPS, DASH scores and quality of life measures. Evidence Level IV; Retrospective observational study.


Objetivo: Avaliar os resultados funcionais do protocolo de tratamento da fratura-luxação transolecraniana, por redução cirúrgica e osteossíntese com placa e parafusos, nos pacientes atendidos em hospital de referência para trauma ortopédico, com seguimento mínimo de seis meses. Métodos: vinte e cinco indivíduos tratados cirurgicamente de janeiro de 2014 a novembro de 2018 foram selecionados para um estudo longitudinal observacional primário, utilizando questionários para avaliar a função do membro superior e cotovelo (DASH e MEPS), qualidade de vida (SF-12), dor (visual escala analógica - EVA), e avaliação radiográfica nas incidências anteroposterior e perfil do cotovelo. Resultados: Quinze pacientes eram do sexo masculino e a média de idade foi de 46,8 anos. Todos os participantes tiveram suas fraturas consolidadas, sem sinais radiográficos de falha do implante ou artrite degenerativa. A amplitude média do movimento foi reduzida em relação ao membro contralateral: 102,6º para flexo-extensão e 132,8º para pronossupinação. Os escores médios de MEPS e DASH foram 89,6 e 16,5, respectivamente. Não houve dor residual em 84% dos casos de acordo com a EAV. Conclusão: O tratamento cirúrgico proposto para a fratura-luxação transolecraniana apresentou resultados satisfatórios de acordo com MEPS, escores DASH e medidas de qualidade de vida. Nível de evidência IV; Estudo observacional retrospectivo.

11.
Viruses ; 15(2)2023 02 01.
Article in English | MEDLINE | ID: mdl-36851627

ABSTRACT

The prevalence and distribution of African alphaviruses such as chikungunya have increased in recent years. Therefore, a better understanding of the local distribution of alphaviruses in vectors across the African continent is important. Here, entomological surveillance was performed from 2014 to 2018 at selected sites in north-eastern parts of South Africa where alphaviruses have been identified during outbreaks in humans and animals in the past. Mosquitoes were collected using a net, CDC-light, and BG-traps. An alphavirus genus-specific nested RT-PCR was used for screening, and positive pools were confirmed by sequencing and phylogenetic analysis. We collected 64,603 mosquitoes from 11 genera, of which 39,035 females were tested. Overall, 1462 mosquito pools were tested, of which 21 were positive for alphaviruses. Sindbis (61.9%, N = 13) and Middelburg (28.6%, N = 6) viruses were the most prevalent. Ndumu virus was detected in two pools (9.5%, N = 2). No chikungunya positive pools were identified. Arboviral activity was concentrated in peri-urban, rural, and conservation areas. A range of Culicidae species, including Culex univittatus, Cx. pipiens s.l., Aedes durbanensis, and the Ae. dentatus group, were identified as potential vectors. These findings confirm the active circulation and distribution of alphaviruses in regions where human or animal infections were identified in South Africa.


Subject(s)
Aedes , Alphavirus , Chikungunya Fever , Animals , Female , Humans , Alphavirus/genetics , Phylogeny , South Africa/epidemiology , Mosquito Vectors
12.
BMJ Open ; 13(1): e069153, 2023 01 12.
Article in English | MEDLINE | ID: mdl-36635033

ABSTRACT

INTRODUCTION: Fibromyalgia is a polysymptomatic syndrome with a prevalence between 0.2% and 13% of the population and causes work disabilities in approximately half of affected patients. Several treatments to fibromyalgia have been proposed with partial improvement. This study aims to evaluate the efficacy of hyperbaric oxygen therapy and when it should be introduced to fibromyalgia. METHODS AND ANALYSIS: This is a protocol for an open-label, crossover, randomised clinical trial comparing treatment with hyperbaric oxygen therapy and standardised treatment to fibromyalgia. In the proposed study, 56 individuals with fibromyalgia will be randomised in a 1:1 ratio into a single, fixed, random block, in which one group will receive hyperbaric oxygen therapy and another will receive standard treatment. Subsequently, the groups will be crossed. Participants will be evaluated at baseline, eight and 16 weeks based on functional impairment assessed with the Fibromyalgia Impact Questionnaire-Brazilian Portuguese version, psychopathological symptoms questionnaire and short-form quality of life questionnaire. The improvement of symptoms concerning the moment of therapy used will be compared between groups. For sample size calculation, a moderate effect size, 80% power and 95% CI will be estimated, in a total of 46 patients. Considering a dropout of 20%, 56 patients should be recruited. ETHICS AND DISSEMINATION: The study was approved by the Universidade Federal de Juiz de Fora Teaching Hospital ethics committee and assigned the number 53058421.9.0000.5133 (version 3). The results will be disseminated via publications in peer-reviewed journals and presentations in medical meetings. TRIAL REGISTRATION NUMBER: RBR-6prps8g)/UTN U1111-1278-3224.


Subject(s)
Fibromyalgia , Hyperbaric Oxygenation , Humans , Fibromyalgia/therapy , Quality of Life , Treatment Outcome , Exercise Therapy/methods , Randomized Controlled Trials as Topic
13.
Bioprocess Biosyst Eng ; 46(1): 53-67, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36409316

ABSTRACT

The enzymatic production of isoamyl levulinate via esterification of isoamyl alcohol (IA) and levulinic acid (LA), a biomass-based platform chemical with attractive properties, in a solvent system has been performed in this study. For such a purpose, a low-cost liquid lipase (Eversa® Transform 2.0) immobilized by physical adsorption via hydrophobic interactions (mechanism of interfacial activation) on mesoporous poly(styrenene-divinylbenzene) (PSty-DVB) beads was used as heterogeneous biocatalyst. It was prepared at low ionic strength (5 mmol.L-1 buffer sodium acetate pH 5.0) and 25 â„ƒ using an initial protein loading of 40 mg.g-1 of support. Maximum protein loading of 31.2 ± 2.8 mg.g-1 of support and an immobilization yield of 83% was achieved. The influence of relevant factors (biocatalyst concentration and reaction temperature) on ester production was investigated using a central composite rotatable design (CCRD). Maximum acid conversion percentage of 65% was achieved after 12 h of reaction at 40 °C, 20% of mass of heterogeneous biocatalyst per mass of reaction mixture (20% m.m-1), and LA:IA molar ratio of 1:1.5 in a methyl isobutyl ketone (MIBK) medium. The biocatalyst retained around of 30% of its initial activity after five consecutive esterification batches under optimal experimental conditions. The proposed experimental procedure can be considered as an acceptable green process (EcoScale score of 66.5), in addition to the fact that a new strategy is proposed to sustainably produce a valuable industrial ester (isoamyl levulinate) from biomass-based materials using an immobilized and low-cost commercial lipase as catalyst.


Subject(s)
Enzymes, Immobilized , Esters , Enzymes, Immobilized/chemistry , Biomass , Esterification , Lipase/chemistry
14.
Biotechnol Appl Biochem ; 70(3): 1291-1301, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36576317

ABSTRACT

The present study consists of developing an enzymatic process for the production of wax esters (lauryl stearate and cetyl stearate) by esterification in a heptane medium. Lipase from Thermomyces lanuginosus (TLL) immobilized via interfacial activation on silica particles from rice husks functionalized with triethoxy(octyl)silane (TLL-Octyl-SiO2 ) was used as biocatalyst. Maximum immobilized protein loading of around 22 mg g-1 (that corresponds to an immobilization yield of ≈55%) of support was observed using an initial protein loading of 40 mg g-1 of Octyl-SiO2 . Its hydrolytic activity (olive oil emulsion hydrolysis) was of 620 U g-1 of biocatalyst. The effect of certain factors on the cetyl estearate production was evaluated using a central composite rotatable design (CCDR). Under optimal conditions (64°C, 21% of mass of biocatalyst per volume of reaction mixture, 170 rpm, and stoichiometric acid:alcohol molar ratio 1 mol L-1 of each reactant), maximum acid conversion percentage of 91% was observed after 60 min of reaction. Lauryl stearate was also produced under such conditions, and an acid conversion of 93% after 60 min of reaction was also achieved. Free lipase exhibited acid conversion of only 15%-20% for both reaction mixtures. After nine successive esterification batches, TLL-Octyl-SiO2 retained 85%-90% of its original activity. These results show the promising use of the prepared biocatalyst in wax esters production due to its high catalytic activity and reusability.


Subject(s)
Lipase , Oryza , Lipase/metabolism , Esterification , Esters , Silicon Dioxide , Adsorption , Stearates , Enzymes, Immobilized/metabolism , Biocatalysis
15.
Eur J Orthop Surg Traumatol ; 33(3): 571-580, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36094673

ABSTRACT

INTRODUCTION: The standard treatment of anterior glenaoid fractures carrying > 20% of the glenoid fossa is open reduction and internal fixation (ORIF). In the herein study, we report our outcomes in a retrospective cohort of anterior and anteroinferior glenoid rim fractures using an accelerated postoperative rehabilitation protocol. A secondary aim is to describe the surgical steps for ORIF of anterior and anteroinferior glenoid rim fractures using the anterior axillary approach, describing the tricks, pearls, and pitfalls of this surgical technique. METHODS: A retrospective cohort of skeletally mature patients treated for an anterior glenoid rim fracture carrying > 20% of the glenoid fossa during a 10-year period were operated on using a vertical axillary incision, osteosynthesis with 2.0-mm cortical screws, and labral repair with small diameter metallic anchors and non-absorbable sutures. Rehabilitation began on the first postoperative day, including passive external rotation exercises and active-assisted flexion, adduction, and abduction exercises as tolerated. The exercises are performed with the patient sitting or lying down. Phase 1 is continued for 6-10 weeks until the patient regains painless, normal, or near-normal ROM. Usually by 10 weeks, the fracture and labrum are healed, so phase 2 rehabilitation begins with strengthening and ROM exercises. Radiologic and clinical outcomes, including active range of motion (ROM), glenohumeral stability, and visual analogue scale (VAS) were measured. RESULTS: About 33 patients (35 fractures) had complete medical records and pre- and post-operative imaging exams available for further analysis regarding the surgical protocol, with a mean of 4.8 years. The mean DASH questionnaire was 3.75 ± 9.0 and the mean CM score was 62.5 ± 0.1. Active flexion and internal rotation were recovered in all patients, while external rotation presented an average loss of 8° (p = 0.12) and abduction of 5° (p = 0.33). The mean VAS was 1.1 ± 0.8. No patient reported major or disabling symptoms, or great difficulty or inability to perform daily or recreational activities. No patient presented residual instability of the glenohumeral joint. CONCLUSION: In this retrospective cohort, ORIF using a vertical axillary incision, osteosynthesis with 2.0-mm screws, and labral repair with small diameter metallic anchors and non-absorbable sutures was a safe approach, with a minimal risk of complications and residual instability. The accelerated postoperative rehabilitation protocol, allowing immediate passive external rotation of the operated shoulder, resulted in a non-significant loss of ROM compared to the contralateral side. Therefore, we recommend this management strategy for anterior glenoid rim fractures in patients with unstable shoulder joint after traumatic glenohumeral dislocation. LEVEL OF EVIDENCE IV: Therapeutic Study (Surgical technique and Retrospective cohort).


Subject(s)
Fractures, Bone , Joint Instability , Shoulder Dislocation , Shoulder Joint , Humans , Retrospective Studies , Scapula/surgery , Fractures, Bone/surgery , Fractures, Bone/complications , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/methods , Shoulder Joint/surgery , Shoulder Dislocation/surgery , Joint Instability/etiology , Range of Motion, Articular , Arthroscopy/methods , Treatment Outcome
16.
Trans R Soc Trop Med Hyg ; 117(3): 179-188, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36153637

ABSTRACT

BACKGROUND: Reports on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread across Africa have varied, including among healthcare workers (HCWs). This study assessed the comparative SARS-CoV-2 burden and associated risk factors among HCWs in three African countries. METHODS: A multicentre study was conducted at regional healthcare facilities in Côte d'Ivoire (CIV), Burkina Faso (BF) and South Africa (SA) from February to May 2021. HCWs provided blood samples for SARS-CoV-2 serology and nasopharyngeal/oropharyngeal swabs for testing of acute infection by polymerase chain reaction and completed a questionnaire. Factors associated with seropositivity were assessed with logistic regression. RESULTS: Among 719 HCWs, SARS-CoV-2 seroprevalence was 34.6% (95% confidence interval 31.2 to 38.2), ranging from 19.2% in CIV to 45.7% in BF. A total of 20 of 523 (3.8%) were positive for acute SARS-CoV-2 infection. Female HCWs had higher odds of SARS-CoV-2 seropositivity compared with males, and nursing staff, allied health professionals, non-caregiver personnel and administration had higher odds compared with physicians. HCWs also reported infection prevention and control (IPC) gaps, including 38.7% and 29% having access to respirators and IPC training, respectively, in the last year. CONCLUSIONS: This study was a unique comparative HCW SARS-CoV-2 investigation in Africa. Seroprevalence estimates varied, highlighting distinctive population/facility-level factors affecting COVID-19 burden and the importance of established IPC programmes to protect HCWs and patients.


Subject(s)
COVID-19 , SARS-CoV-2 , Male , Humans , Female , Burkina Faso , Cote d'Ivoire , South Africa , Seroepidemiologic Studies , Health Personnel
17.
World J Microbiol Biotechnol ; 39(1): 25, 2022 Nov 24.
Article in English | MEDLINE | ID: mdl-36422728

ABSTRACT

In recent years, fluctuating global fossil fuel market prices and growing concern about environmental pollution have increased efforts to obtain novel value-added products from renewable agricultural biomass. To this end, a wide variety of triacylglycerols (edible and non-edible oils and fats) and their derivatives (free fatty acids or monoalkyl esters) stand out as promising feedstocks for the production of biolubricant base stocks, due to their biodegradability, excellent physicochemical properties, and sustainable nature. These raw materials can be transformed into biolubricants using chemical or biochemical (lipases) catalysts, with the enzymatic production of biolubricants using lipases as catalysts being recognized as an environmentally friendly approach. The present mini-review highlights recent advances in this field, published in the last three years. The different chemical modification processes used to develop a wide variety of industrial biolubricant base stocks are comprehensively reviewed, with exploration of future prospects for industrial production via the enzymatic route. This study contributes to the current state-of-the-art, identifying relevant research questions and providing important technical information for new applications of lipases in oleochemical manufacturing industries.


Subject(s)
Esters , Lipase , Triglycerides , Plant Oils , Industry
18.
Viruses ; 14(7)2022 07 05.
Article in English | MEDLINE | ID: mdl-35891456

ABSTRACT

Bagaza virus (BAGV), a member of the Ntaya serogroup in the Flavivirus genus of the Flaviviridae, was isolated from the brain tissue of a Himalayan monal pheasant that died following neurological signs in Pretoria, South Africa in 2016. Next-generation sequencing was carried out on this isolate resulting in a genome sequence of 10980nt. The full genome sequence of this isolate, designated ZRU96-16, shared 98% nucleotide identity with a BAGV isolate found in Culex univitattus mosquitoes from Namibia and 97% nucleotide identity with a Spanish BAGV sequence isolated from an infected partridge. In total, seven amino acid variations were unique to ZRU96-16 after alignment with other BAGV and Israel turkey meningoencephalomyelitis (ITV) genomes. The 3'UTR sequence of ZRU96-16 was resolved with sufficient detail to be able to annotate the variable and conserved sequence elements within this region. Multiple sequence alignment of the 3'UTR suggested that it could be useful in lineage designation as more similar viruses carried similar mutations across this region, while also retaining certain unique sites. Maximum likelihood phylogenetic analysis revealed two clusters containing both BAGV and ITVs from Europe, the Middle East and Africa. Broadly, temporal clustering separated isolates into two groups, with one cluster representing viruses from the 1960-2000's and the other from 2010 onwards. This suggests that there is consistent exchange of BAGV and ITV between Europe and Africa. This investigation provides more information on the phylogenetics of an under-represented member of the Flaviviridae and provides an avenue for more extensive research on its pathogenesis and geographic expansion.


Subject(s)
Flaviviridae , Flavivirus , Galliformes , 3' Untranslated Regions , Animals , Flaviviridae/genetics , Genome, Viral , Nucleotides , Phylogeny , South Africa
20.
Cell Host Microbe ; 30(6): 880-886.e4, 2022 06 08.
Article in English | MEDLINE | ID: mdl-35436444

ABSTRACT

The SARS-CoV-2 Omicron variant escapes neutralizing antibodies elicited by vaccines or infection. However, whether Omicron triggers cross-reactive humoral responses to other variants of concern (VOCs) remains unknown. We used plasma from 20 unvaccinated and 7 vaccinated individuals infected by Omicron BA.1 to test binding, Fc effector function, and neutralization against VOCs. In unvaccinated individuals, Fc effector function and binding antibodies targeted Omicron and other VOCs at comparable levels. However, Omicron BA.1-triggered neutralization was not extensively cross-reactive for VOCs (14- to 31-fold titer reduction), and we observed 4-fold decreased titers against Omicron BA.2. In contrast, vaccination followed by breakthrough Omicron infection associated with improved cross-neutralization of VOCs with titers exceeding 1:2,100. This has important implications for the vulnerability of unvaccinated Omicron-infected individuals to reinfection by circulating and emerging VOCs. Although Omicron-based immunogens might be adequate boosters, they are unlikely to be superior to existing vaccines for priming in SARS-CoV-2-naive individuals.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Humans , Neutralization Tests
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