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BACKGROUND: Perilunate dislocations and perilunate fracture dislocations (PLD/PLFDs) are rare injuries of the wrist, with surgical management leading to acceptable functional results. PURPOSE: The purpose of this study was to assess the functional outcomes of the patients of our department who were treated with surgical management of PLDs/PLFDs through dorsal approach, as well as to report any complications on their follow-up. PATIENTS AND METHODS: In this retrospective study, 52 patients with PLD/PLFD, fulfilling the inclusion and exclusion criteria of the study, underwent surgical management of their injury. All patients were followed up at 6 weeks, 12 weeks, 6 months, 1 year postoperatively with radiographic imaging as well as functional scores measured with the modified mayo wrist score and the QuickDASH questionnaire. RESULTS: The mean postoperative modified Mayo score was 76.8 ± 8.8 and the mean QuickDASH score was 1.52 ± 2.18. Of the 52 cases, 20% had excellent results, 42% had good results, 29% had fair results and 9% had poor results as per the modified Mayo wrist score. No patient signed any symptoms of median nerve neuropathy. CONCLUSION: In conclusion, open reduction and internal fixation through dorsal approach is a reliable technique to manage perilunate injuries in spite of radiological evidence of wrist arthritis, as it also provides consistently good results in terms of functional outcomes. LEVEL OF EVIDENCE IV: Retrospective case series study.
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Fratura-Luxação , Fixação Interna de Fraturas , Osso Semilunar , Traumatismos do Punho , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Osso Semilunar/lesões , Osso Semilunar/cirurgia , Osso Semilunar/diagnóstico por imagem , Fixação Interna de Fraturas/métodos , Fratura-Luxação/cirurgia , Fratura-Luxação/diagnóstico por imagem , Pessoa de Meia-Idade , Resultado do Tratamento , Traumatismos do Punho/cirurgia , Traumatismos do Punho/fisiopatologia , Traumatismos do Punho/diagnóstico por imagem , Adulto Jovem , Radiografia , Luxações Articulares/cirurgia , Luxações Articulares/diagnóstico por imagem , Amplitude de Movimento Articular , Articulação do Punho/fisiopatologia , Articulação do Punho/cirurgia , Articulação do Punho/diagnóstico por imagem , Recuperação de Função Fisiológica , AdolescenteRESUMO
White cord syndrome is a rare entity, as there are very few cases described in the current literature. Postoperative MRI examination reveals cord intrinsic changes, including edema and ischemia. It is also described as a reperfusion injury of the spinal cord. This report depicts a rare case of "white cord syndrome" with tetraplegia after posterior laminectomy and fusion of the cervical spine in a patient with Klippel-Feil syndrome. A 33-year-old male patient with Klippel-Feil syndrome presented to our department with cervical myelopathy, claudication, deteriorating neurological status, imbalance, and lower limb spasticity. Due to kyphotic malformation of the cervical spine, a two-stage surgical intervention was scheduled. The patient first underwent anterior spinal fusion of C4-C6 with corpectomy of C5, where many anatomical and visceral differentiations were signed, so the surgical team was enhanced by a vascular surgeon. The postoperative period was uneventful and the patient was discharged after a week of hospitalization without any neurological deterioration. A second surgical intervention was scheduled after two months where laminectomy of C5-C7 and posterior fusion of C5-T1 were carried out. However, due to intraoperative spinal instability and various anatomical spinal variations, a third surgery, which would be occipitocervical fusion, was decided as the final surgical solution. During the third surgical operation, after the laminectomy of C1 to C5 and the placement of the occipital plate, the screws, and the two rods in situ, complete nullification of the intraoperative neurophysiologic control was signed. The internal fixation was removed immediately, the wake-up test revealed tetraplegia below C5, and the patient was transferred to the ICU. Immediate MRI revealed no spinal cord hematoma; however, spinal cord edema was present. The patient underwent a tracheostomy and remained quadriplegic with a sensory level of T8 and motor level of C5 and was discharged to a rehabilitation center. The possibility of white cord syndrome should be explained by surgeons before any cervical decompression surgery, as well as a thorough neurological examination should be performed postoperatively. The early recognition and prompt management of white cord syndrome is recommended.
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There are limited reports about managing knee flexion contracture (KFC) due to hemophilic hemarthrosis with the Ilizarov technique and platelet-rich plasma intraarticular injection administration. This article aims to describe a case of KFC treated with a circular external fixator and intraarticular administration of platelet-rich plasma in a pediatric patient. A 12-year-old male patient suffering from hemophilia A was being monitored by our department due to knee effusions. Extensive knee flexion contracture of the left knee was seen. The Ilizarov technique was chosen for surgical management of the worsening knee flexion contracture. The duration of distraction was six weeks. Due to localized pain and functional impairment, intra-articular administration of platelet-rich plasma (PRP) was applied twice, on the first month after the circular frame removal and at a six-month follow-up, with clinical and functional improvement. Our clinical case report demonstrates that PRP intra-articular injections are likely to provide an improvement in pain and knee joint function, as well as joint hyperemia, even in the case of already established knee flexion contracture, which was managed with a circular distraction device. However, more studies regarding the Ilizarov technique and the PRP intraarticular administration are needed for a protocol to be established for the management of the hemophilic knee joint in the pediatric population.
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Congenital deformities of the spine lead to an imbalance in the longitudinal growth of the spine. These growth abnormalities may lead to three main patterns of deformity: scoliosis (the most common), kyphosis or lordosis (the least common). Despite the recent improvements in imaging and the routine use of neuromonitoring in the surgical treatment of congenital kyphosis, this surgery may be associated with a high rate of complications such as neurologic deficit, pulmonary thromboembolic events, infection, deep vein thrombosis, implant failure, and dural injury. In this paper, we report a rare yet devastating complication to raise awareness about patients who have unexpected neurological deterioration after spinal surgery. Early recognition of remote cerebellar haemorrhage (RCH) symptoms is crucial since rapid diagnosis and management lead to a favourable outcome for this potentially life-threatening complication. To our knowledge, this is the first reported case in children.
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INTRODUCTION: Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes, while the exact mechanisms underlying its pathophysiology are still unclear. We investigated the association of glucagon-like peptide-1 (GLP-1) response to oral glucose with parameters of glycemic control in women with previous GDM in the prospective PPSDiab (Prediction, Prevention, and Subclassification of Type 2 Diabetes) study. RESEARCH DESIGN AND METHODS: Glucose metabolism parameters and GLP-1 secretion were analyzed during oral glucose tolerance test (OGTT) in women with previous GDM (n=129) and women with a history of normal glucose tolerance (n=67) during pregnancy (controls). First- and second-phase insulin and GLP-1 secretion in relation to plasma glucose (PG) levels were assessed, and development of pre-diabetes was analyzed after 5-year follow-up among women with previous GDM and a normal glycemic state at baseline (n=58). RESULTS: The area under the curve (AUC during the OGTT 0-120 min) of PG and insulin but not GLP-1 differed significantly between post-GDM women and controls. However, women with previous GDM had a significantly decreased GLP-1 response in relation to PG and plasma insulin during the second phase of the OGTT. After a follow-up of 5 years, 19.0% post-GDM women with a normal glycemic state at the baseline visit developed abnormal glucose metabolism. The total, first- and second-phase AUC GLP-1/PG and GLP-1/insulin ratios were not associated with development of abnormal glucose tolerance. CONCLUSIONS: Women with previous GDM showed a reduced GLP-1 response in relation to PG and insulin concentrations indicating early abnormalities in glucose metabolism. However, the altered GLP-1 response to oral glucose did not predict progression to pre-diabetes and type 2 diabetes in the first 5 years after GDM.
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Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Estado Pré-Diabético , Gravidez , Humanos , Feminino , Controle Glicêmico , Estudos Prospectivos , Insulina Regular Humana , Insulina , Peptídeo 1 Semelhante ao Glucagon , GlucoseRESUMO
Neuroblastoma (NB), the most frequent solid extracranial tumor in children, is not always cured by current aggressive therapies that have notable adverse effects; therefore, novel treatments are necessary. Phosphoinositide 3kinase (PI3K) and fibroblast growth factor receptor inhibitors exhibit synergistic effect in NB cell lines. In the present study, mono and combination therapy of the United States Food and Drug Administrationapproved PI3K, cyclindependent kinase4/6 (CDK4/6), polyADPribosepolymerase (PARP) and WEE1 G2 checkpoint kinase (WEE1) inhibitors (BYL719, PD0332991, BMN673 and MK1775, respectively), were used to treat NB cell lines SKNAS, SKNBE(2)C, SKNDZ, SKNFI and SKNSH and viability (assessed by WST1 assay), proliferation (incucyte analysis) and cell cycle (FACS) changes were assessed. Treatments with all single drugs presented dose-dependent responses with decreased viability and proliferation and combining BYL719 with PD0332991 or BMN673 with MK1775 resulted in additive or synergistic effects in most cell lines., except for SKNSH for the former and for SKNAS for the latter. Moreover, combining MK1775 and BMN673 decreased the numbers of cells in S phase to a greater extent than either drug alone, while when combining PD0332991 and BYL719 the observed effect was close to that of PD0332991 alone. To summarize, PI3K and CDK4/6 or PARP and WEE1 exhibited synergistic antiNB effects and lower doses of the inhibitors could be utilized, thereby potentially reducing adverse side effects.
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Neuroblastoma , Fosfatidilinositol 3-Quinases , Criança , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Fosfatidilinositol 3-Quinase , Linhagem Celular Tumoral , Proliferação de Células , Neuroblastoma/tratamento farmacológico , Proteínas de Ciclo Celular/metabolismo , Proteínas Tirosina Quinases , Quinase 4 Dependente de CiclinaRESUMO
Greece has a long tradition in cheesemaking, with 22 cheeses registered as protected designation of origin (PDO), 1 as protected geographical indication (PGI), and 1 applied for PGI. Several other cheeses are produced locally without any registration, which significantly contribute to the local economy. The present study investigated the composition (moisture, fat, salt, ash, and protein content), color parameters, and oxidative stability of cheeses that do not have a PDO/PGI certification, purchased from a Greek market. Milk and cheese types were correctly assigned for 62.8 and 82.1 % of samples, respectively, through discriminant analysis. The most important factors for milk type discrimination were L, a and b color attributes, salt, ash, fat-in-dry-matter, moisture-in-non-fat-substance, salt-in-moisture, and malondialdehyde contents, whereas a and b, and moisture, ash, fat, moisture-in-non-fat substance contents, and pH were the most influential characteristics for sample discrimination according to cheese type. A plausible explanation may be the differences in milk chemical composition between three animal species, namely cows, sheep, and goats and for the manufacture procedure and ripening. This is the very first report on the proximate analysis of these, largely ignored, chesses aiming to simulate interest for further study and production valorization.
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The application of manures leads to the contamination of agricultural soils with veterinary antibiotics (VAs). These might exert toxicity on the soil microbiota and threaten environmental quality, and public health. We obtained mechanistic insights about the impact of three VAs, namely, sulfamethoxazole (SMX), tiamulin (TIA) and tilmicosin (TLM), on the abundance of key soil microbial groups, antibiotic resistance genes (ARGs) and class I integron integrases (intl1). In a microcosm study, we repeatedly treated two soils (differing in pH and VA dissipation capacity) with the studied VAs, either directly or via fortified manure. This application scheme resulted in accelerated dissipation of TIA, but not of SMX, and accumulation of TLM. Potential nitrification rates (PNR), and the abundance of ammonia-oxidizing microorganism (AOM) were reduced by SMX and TIA, but not by TLM. VAs strongly impacted the total prokaryotic and AOM communities, whereas manure addition was the main determinant of the fungal and protist communities. SMX stimulated sulfonamide resistance, while manure stimulated ARGs and horizontal gene transfer. Correlations identified opportunistic pathogens like Clostridia, Burkholderia-Caballeronia-Paraburkholderia, and Nocardioides as potential ARG reservoirs in soil. Our results provide unprecedented evidence about the effects of understudied VAs on soil microbiota and highlight risks posed by VA-contaminated manures. ENVIRONMENTAL IMPLICATION: The dispersal of veterinary antibiotics (VAs) through soil manuring enhances antimicrobial resistance (AMR) development and poses a threat to the environment and the public health. We provide insights about the impact of selected VAs on their: (i) microbially-mediated dissipation in soil; (ii) ecotoxicity on the soil microbial communities; (iii) capacity to stimulate AMR. Our results (i) demonstrate the effects of VAs and their application-mode on the bacterial, fungal, and protistan communities, and on the soil ammonia oxidizers; (ii) describe natural attenuation processes against VA dispersal, (iii) depict potential soil microbial AMR reservoirs, essential for the development of risk assessment strategies.
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Antibacterianos , Solo , Solo/química , Antibacterianos/farmacologia , Sulfametoxazol/química , Esterco/microbiologia , Microbiologia do Solo , Amônia/farmacologia , Genes Bacterianos , Farmacorresistência Bacteriana/genéticaRESUMO
Background and objective ApiFix (OrthoPediatrics, Warsaw, IN) is an internal brace used for the correction of adolescent idiopathic scoliosis (AIS) classified as Lenke 1 or 5 with a Cobb angle of 35-60 degrees that decreases to ≤30 degrees on lateral side-bending radiographs. Since the indications are very specific, it is not a common procedure. Our study aimed to evaluate the incidence of surgical site infection (SSI) and its recurrence following treatment with ApiFix. Materials and methods A retrospective study of 44 cases of AIS treated at our center from 2016 to 2022 with ApifiX was conducted. Two patients who presented with SSI were initially treated with irrigation and debridement (I&D) following antibiotic therapy. Results A total of 44 patients with a mean age of 15.1 years were evaluated. Two of our patients presented with early-onset infection while one of them presented after the end of treatment with a skin ulcer due to septic screw loosening. The removal of the ApiFix implant revealed a pedicle abscess during the screw removal. Conclusions In this study of 44 patients, we observed two cases of infection and one case of reinfection. Given the limited muscle detachment and short operating time needed for Apifix, statistics suggest that the risk of SSI is always present. Further randomized trials are needed to gather more evidence on this subject.
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The aim of this review and meta-analysis is to assess recent clinical trials concerning the combination of operative treatment of rotator cuff tears and the administration of PRP and its effect on clinical scores and postoperative retear rates. The trials were used to compare the combination of PRP treatment and arthroscopic rotator cuff repair to arthroscopy alone. Twenty-five clinical trials were reviewed. A risk-of-bias assessment was made for all randomized clinical trials included, using the Cochrane collaboration's tool as well as a quality assessment for all non-randomized studies utilizing the Newcastle−Ottawa scale. The PRP-treated patients showed statistically significant improvement postoperatively compared to control groups concerning the Constant−Murley (mean difference 2.46, 95% CI 1.4−3.52, p < 0.00001), SST (mean difference 0.32, 95% CI 0.02−0.63, p = 0.04), and UCLA (mean difference 0.82, 95% CI 0.23−1.43, p = 0.07) scores. A statistically significant decrease of retear rates in the PRP-treated patients, with a risk ratio of 0.78 (95% CI 0.65−0.94, p = 0.01), was found. We believe that the results presented have positive aspects, especially concerning the retear risk, but are yet inconclusive concerning clinical results such as shoulder pain and function.
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Background and objective: Fat content in bones and muscles, quantified by magnetic resonance imaging (MRI) as a proton density fat fraction (PDFF) value, is an emerging non-invasive biomarker. PDFF has been proposed to indicate bone and metabolic health among postmenopausal women. Premenopausal women with a history of gestational diabetes (GDM) carry an increased risk of developing type 2 diabetes and an increased risk of fractures. However, no studies have investigated the associations between a history of GDM and PDFF of bone or of paraspinal musculature (PSM), composed of autochthonous muscle (AM) and psoas muscle, which are responsible for moving and stabilizing the spine. This study aims to investigate whether PDFF of vertebral bone marrow and of PSM are associated with a history of GDM in premenopausal women. Methods: A total of 37 women (mean age 36.3 ± 3.8 years) who were 6 to 15 months postpartum with (n=19) and without (n=18) a history of GDM underwent whole-body 3T MRI, including a chemical shift encoding-based water-fat separation. The PDFF maps were calculated for the vertebral bodies and PSM. The cross-sectional area (CSA) of PSM was obtained. Associations between a history of GDM and PDFF were assessed using multivariable linear and logistic regression models. Results: The PDFF of the vertebral bodies was significantly higher in women with a history of GDM (GDM group) than in women without (thoracic: median 41.55 (interquartile range 32.21-49.48)% vs. 31.75 (30.03-34.97)%; p=0.02, lumbar: 47.84 (39.19-57.58)% vs. 36.93 (33.36-41.31)%; p=0.02). The results remained significant after adjustment for age and body mass index (BMI) (p=0.01-0.02). The receiver operating characteristic curves showed optimal thoracic and lumbar vertebral PDFF cutoffs at 38.10% and 44.18%, respectively, to differentiate GDM (AUC 0.72 and 0.73, respectively, sensitivity 0.58, specificity 0.89). The PDFF of the AM was significantly higher in the GDM group (12.99 (12.18-15.90)% vs. 10.83 (9.39-14.71)%; p=0.04) without adjustments, while the CSA was similar between the groups (p=0.34). Conclusion: A history of GDM is significantly associated with a higher PDFF of the vertebral bone marrow, independent of age and BMI. This statistical association between GDM and increased PDFF highlights vertebral bone marrow PDFF as a potential biomarker for the assessment of bone health in premenopausal women at risk of diabetes.
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Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Humanos , Feminino , Gravidez , Adulto , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Diabetes Gestacional/patologia , Prótons , Corpo Vertebral , Diabetes Mellitus Tipo 2/patologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Vértebras Lombares/diagnóstico por imagem , BiomarcadoresRESUMO
Limbus vertebra is a common radiological finding in an adult, especially in the mid-lumbar region. However it is less commonly seen in the mid cervical region. A case of an anterior limbus vertebra seen on the cervical spine on an adult suffering from a T5 fracture is reported.
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AIMS: Administration of insulin degludec and liraglutide (IDegLira) correlates to fasting lipid profile changes of diabetic patients, while data concerning apoB-containing lipoprotein subclasses and HDL lipidome are scarce. We evaluated its effect on fasting lipid parameters, apolipoproteins, apoB-containing lipoprotein subclasses and HDL lipidome in patients with type 2 diabetes. METHODS: Sixty three patients with HbA1c > 7 % on oral glucose-lowering drugs received either IDegLira or insulin degludec for 3 months. Lipoprotein subfraction profile was determined through Lipoprint method, whereas HDL lipid composition via 1H NMR. RESULTS: Compared to insulin degludec, IDegLira administration resulted in significantly greater reduction of total and LDL-cholesterol. On the other hand, the effect of the two drugs on apolipoprotein-B-containing lipoprotein subfractions concentration was minimal and did not differ between the 2 interventions. IDegLira, but not insulin degludec, induced an atheroprotective shift in HDL's fatty acid composition and particle core depletion in triglycerides. CONCLUSIONS: IDegLira administration is accompanied by total and LDL-cholesterol reduction, while sdLDL concentration only reduced in patients experiencing triglyceride reduction. IDegLira induced compositional changes of HDL particles. These changes may contribute to the cardioprotective properties of liraglutide.
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Diabetes Mellitus Tipo 2 , Liraglutida , Apolipoproteínas B , Glicemia , LDL-Colesterol , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácidos Graxos , Glucose , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Insulina de Ação Prolongada , Lipidômica , Lipoproteínas , Liraglutida/efeitos adversos , TriglicerídeosRESUMO
Proximal tibiofibular joint (PTFJ) arthritis is rare and, thus, not regularly considered as a source of knee pain. In this report, we present the case of a patient with posterior knee pain attributed to a medial meniscal tear rather than to a co-existing PTFJ arthritis, which was not appreciated. Based on the initial diagnosis, the patient underwent knee arthroscopy that did not alleviate his symptoms. The presence of established tibiofibular joint arthritis was diagnosed on subsequent clinical and MRI reassessment. An intra-articular corticosteroid injection settled the patient's symptoms. The aim of this report is to raise awareness about tibiofibular joint arthritis as a possible cause of posterior or lateral knee pain.
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OBJECTIVE: To investigate the impact of metabolic status on choroidal thickness (ChT) in healthy subjects, patients with obesity, and type 2 diabetes. DESIGN AND METHODS: Fasting blood glucose, insulin, insulin-like growth factor-1 (IGF-1), and ChT measured by optical coherence tomography were assessed in healthy normal-weight (n=17), obese participants (n=20), and obese participants with T2D (n=16). RESULTS: ChT increased in obese participants and obese participants with T2D as compared to healthy normal-weight participants (P<0.0001). A negative correlation was observed between IGF1 and ChT (r=-0.268, P=0.050) for all cohorts. Furthermore, body mass index (BMI; R2=0.209; P=0.002; beta=0.388) and model assessment-estimated insulin resistance (HOMA-IR; R2=0.074; P=0.015; beta=0.305) were independent variables of ChT, explaining 20.9 and 7.4% of its variance (both p<0.016), whereas age, sex, and IGF-1 were not significant confounders of ChT (p>0.975). CONCLUSION: ChT is associated with metabolic characteristics, i. e., BMI and HOMA-IR. Due to the key role of choroidal function in retinal physiology, future studies are needed to evaluate whether metabolic traits, ChT, and potential metabolic eye complications are mechanistically linked.
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Corioide , Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Humanos , Glicemia , Índice de Massa Corporal , Corioide/diagnóstico por imagem , Corioide/metabolismo , Complicações do Diabetes/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina/fisiologia , Fator de Crescimento Insulin-Like I , Obesidade/complicações , Obesidade/metabolismoRESUMO
The aim of this case report is to present a rare case of acute slipped femoral capital on a chronic slipped capital femoral epiphysis (SCFE) after spinal fusion due to idiopathic scoliosis. A 14 year old male patient underwent posterior spinal fusion due to idiopathic thoracic scoliosis. Post-operatively, the patient presented with acute pain in the left hip and a reduced range of motion, which revealed acute SCFE. The patient was then referred to the Second Orthopaedic Department of Agia Sofia Children Hospital in Athens, and underwent percutaneous pinning of the left femur, after which he was discharged uneventfully. The follow up was excellent with no impact on the patient's daily life. The case described is extremely rare in the current literature. The significance of the pre-operative planning is underlined by this case, as well as the need for the spinal surgeon to be aware of the possibility of acute pain in the hip in young adolescents, as SCFE is more common amongst this demographic.
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In the present work, a fresh spreadable cheese from ovine milk with or without (control) fortification with ß-glucan was manufactured. ß-Glucan was extracted from the mushroom Pleurotus ostreatus and its concentration in the cheese was 0.4% (w/w). The composition, biochemical, and sensory properties of the cheeses during 21 days of storage were determined. At the end of storage, cheese fortified with beta-glucan had 75.26% moisture content, 10.30% fat, 1.71% salt, and 8.50% protein. Generally, the addition of ß-glucan at this concentration did not significantly affect the composition, color, and viscosity measurements or the level of proteolysis and lipolysis and the antioxidant activity of the cheeses. However, cheese fortified with ß-glucan showed a higher moisture content than control cheese on the 1st and 21st day of storage while the levels of proteolysis and the sensory properties of the cheeses were unaffected. During the sensory evaluation, panelists evaluated cheese with ß-glucan with higher scores regarding the flavor characteristic compared to control cheese. The major free fatty acid was acetic acid in both cheeses and its concentration was higher in cheese with ß-glucan. The results of the present study could be used by the dairy industry for manufacturing new products with improved health benefits.
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The aim of the present study was to examine 189 LAB strains belonging to the species Enterococcus faecium, E. faecalis, Lactococcus lactis, Pediococcus pentosaceus, Leuconostoc mesenteroides, Lactiplantibacillus pentosus, Latilactobacillus curvatus, Lp. plantarum, Levilactobacillus brevis, and Weissella paramesenteroides isolated form sheep milk, Feta and Kefalograviera cheeses at different ripening stages, for their technological compatibility with dairy products manufacturing, their activities that may compromise safety of the dairy products as well as their capacity to survive in the human gastrointestinal tract. For that purpose, milk acidification and coagulation capacity, caseinolytic, lipolytic, hemolytic, gelatinolytic, and bile salt hydrolase activity, production of exopolysaccharides, antimicrobial compounds, and biogenic amines, as well as acid and bile salt tolerance and antibiotic susceptibility were examined. The faster acidifying strains were Lc. lactis DRD 2658 and P. pentosaceus DRD 2657 that reduced the pH value of skim milk, within 6 h to 5.97 and 5.92, respectively. Strains able to perform weak caseinolysis were detected in all species assessed. On the contrary, lipolytic activity, production of exopolysaccharides, amino acid decarboxylation, hemolytic, gelatinase, and bile salt hydrolase activity were not detected. Variable susceptibility to the antibiotics examined was detected among LAB strains. However, in the majority of the cases, resistance was evident. None of the strains assessed, managed to survive to exposure at pH value 1. On the contrary, 25.9 and 88.9% of the strains survived after exposure at pH values 2 and 3, respectively; the reduction of the population was larger in the first case. The strains survived well after exposure to bile salts. The strain-dependent character of the properties examined was verified. Many strains, belonging to different species, have presented very interesting properties; however, further examination is needed before their potential use as starter or adjunct cultures.
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Artisanal cheesemaking is still performed using practices and conditions derived from tradition. Feta and Kefalograviera cheeses are very popular in Greece and have met worldwide commercial success. However, there is a lack of knowledge regarding their lactic acid microecosystem composition and species dynamics during ripening. Thus, the aim of the present study was to assess the microecosystem as well as the autochthonous lactic acid microbiota during the ripening of artisanal Feta and Kefalograviera cheeses. For that purpose, raw sheep's milk intended for cheesemaking, as well as Feta and Kefalograviera cheeses during early and late ripening were analyzed, and the lactic acid microbiota was identified using the classical phenotypic approach, clustering with PCR-RAPD and identification with sequencing of the 16S-rRNA gene, as well as with the Biolog GEN III microplates. In addition, the functional properties of the bacterial community were evaluated using the Biolog EcoPlates, which consists of 31 different carbon sources. In general, concordance between the techniques used was achieved. The most frequently isolated species from raw sheep's milk were Enteroroccus faecium, Lactiplantibacillus plantarum and Pediococcus pentosaceus. The microecosystem of Feta cheese in the early ripening stage was dominated by Lp. plantarum and E. faecium, whereas, in late ripening, the microecosystem was dominated by Weissella paramesenteroides. The microecosystem of Kefalograviera cheese in the early ripening stage was dominated by Levilactobacillus brevis and E. faecium, and in late ripening by W. paramesenteroides and E. faecium. Finally, Carbohydrates was the main carbon source category that metabolized by all microbial communities, but the extent of their utilization was varied. Kefalograviera samples, especially at early ripening, demonstrated higher metabolic activity compared to Feta cheese. However, dominating species within microbial communities of the cheese samples were not significantly different.