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1.
Sci Total Environ ; 904: 166844, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37689207

RESUMO

The Chernobyl Nuclear Power Plant (ChNPP) accident in 1986 resulted in extremely high levels of acute ionising radiation, that killed or damaged Scots pine (Pinus sylvestris) trees in the surrounding areas. Dead trees were cleared and buried, and new plantations established a few years later. Today, more than three decades later, gamma and beta-radiation near the ChNPP is still elevated compared with ambient levels but have decreased by a factor of 300 and 100, respectively. In the present work, Scots pine-trees growing at High (220 µGy h-1), Medium (11 µGy h-1), and Low (0.2 µGy h-1) total (internal + external) dose rates of chronically elevated ionising radiation in the Chernobyl Exclusion zone were investigated with respect to possible damage to DNA, cells and organelles, as well as potentially increased levels of phenolic and terpenoid antioxidants. Scots pine from the High and Medium radiation sites had elevated levels of DNA damage in shoot tips and needles as shown by the COMET assay, as well as increased numbers of resin ducts and subcellular abnormalities in needles. Needles from the High radiation site showed elevated levels of monoterpenes and condensed tannins compared with those from the other sites. In conclusion, more than three decades after the ChNPP accident substantial DNA damage and (sub)cellular effects, but also mobilisation of stress-protective substances possessing antioxidant activity were observed in Scots pine trees growing at elevated levels of ionising radiation. This demonstrates that the radiation levels in the Red Forest still significantly impact the plant community.


Assuntos
Acidente Nuclear de Chernobyl , Pinus sylvestris , Pinus , Monitoramento de Radiação , Radiação Ionizante , Árvores , Florestas
2.
Front Psychiatry ; 14: 1163347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229394

RESUMO

Objective: Evidence-based personality disorder (PD) treatments are dominated by interventions targeting Borderline PD, although clinical populations characteristically include different PD features and severity. Personality functioning is a new concept intended to capture common features across PDs. This study aimed to investigate longitudinal improvement of personality functioning in a clinical sample assigned to PD treatment. Method: An observational, large, longitudinal study of patients in PD treatments on specialist mental health service levels (N = 1,051). DSM-5 PDs were systematically assessed on referral. Personality functioning was repeatedly assessed (LPFS-BF-2.0), supplemented by symptom distress (anxiety: PHQ-GAD-7, depression: PHQ-9), and social/occupational activity (WSAS, work/study activity). Statistics were linear mixed models. Results: Thirty per cent had personality difficulties below PD threshold. Among PDs, 31% had Borderline (BPD), 39% Avoidant (AvPD), 15% not otherwise specified, 15% other PDs, and 24% > one PD. More severe initial LPFS-BF was associated with younger age, presence of PD and increasing number of total PD criteria. Across PD conditions, LPFS-BF, PHQ-9 and GAD-7 improved significantly (overall effect size 0.9). Mean duration of PD treatment was 15 (SD 9) months. Drop-out rates were low (12%). LPFS-BF improvement-rates were higher for BPD. Younger age was moderately associated with slower PHQ-9 improvement. Work/study activity was initially poor, poorer levels associated with AvPD and younger age, and improvement was non-significant across PD conditions. AvPD was associated with slower WSAS improvement-rates. Conclusion: Personality functioning improved across PD conditions. The results highlight BPD improvements. The study points to challenges concerning AvPD treatment, poor occupational activity and age-related differences.

4.
Ann Surg Oncol ; 29(10): 6327-6336, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35876920

RESUMO

BACKGROUND: One fourth of early-stage breast cancer cases become metastatic during the follow-up period. Limited metastasis is a metastatic disease condition in which the number of metastatic sites and the extent of the disease both are limited, and the disease is amenable to metastatic intervention. This prospective study aimed to evaluate intervention for limited metastases in the lung, liver, or both. METHODS: The study enrolled luminal A/B and/or human epidermal growth factor receptor 2 (HER2)-neu+ patients with operable lung and/or liver metastases in the follow-up assessment after completion of primary breast cancer treatment and patients with a diagnosis of metastasis after 2014. Demographic, clinical, tumor-specific, and metastasis detection-free interval (MDFI) data were collected. Bone metastasis in addition to lung and liver metastases also was included in the analysis. The patients were divided into two groups according to the method of treatment for metastases: systemic therapy alone (ST) group or intervention (IT) group. RESULTS: Until June 2020, 200 patients were enrolled in the study. The demographic data were similar between the two groups. The median follow-up time was 77 months (range 55-107 months) in the IT group (n = 119; 59.5%) and 57 months (range 39-84) in the ST-only group (n = 81; 40.5%). The median MDFI was 40 months (range 23-70 months) in the IT group, and 35 months (range 13-61 months) in the ST-only group (p = 0.47). The groups had similar surgeries for the primary tumor and axilla. Most of the patients had liver metastases (49.5%, n = 99), and 42% (n = 84) of the patients had lung metastases. Both lung and liver metastases were found in 8.5% (n = 17) of the patients. The primary tumor was estrogen receptor/progesterone receptor-positive in 75% (n = 150) of the patients, and 32% (n = 64) of the patients had HER2-neu+ tumors. Metastatic-site resection was performed for 32% (n = 64) of the patients, and 27.5% (n = 55) of the patients underwent metastatic ablative interventions. In the Kaplan-Meier survival analysis, the hazard of death (HoD) was 56% lower in the IT group than in the ST-only group (hazard ratio [HR], 0.44; 95% confidence interval [CI] 0.26-0.72; p = 0.001). The HoD was lower in the IT group than in the ST-only group for the patients younger than 55 years (HR, 0.32; 95% CI 0.17-0.62; p = 0.0007). In the multivariable Cox regression model, HoD was significantly lower for the patients who underwent intervention for metastases and had an MDFI longer than 24 months, but their liver metastases doubled the risk of death compared with lung metastases. CONCLUSION: Metastasis-directed interventions have reduced the risk of death for patients with limited lung/liver metastases who are amenable to interventions after completion of primary cancer treatment. For a select group of patients, such as those with luminal A/B or HER2-neu+ breast cancer who are younger than 55 years with limited metastases to the lung and liver or an MDFI longer than 24 months, surgical or ablative therapy for metastases should be considered and discussed on tumor boards.


Assuntos
Neoplasias da Mama , Neoplasias Hepáticas , Neoplasias Pulmonares , Neoplasias da Mama/tratamento farmacológico , Feminino , Histamina/análogos & derivados , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Sistema de Registros , Estudos Retrospectivos
5.
Neurogastroenterol Motil ; 34(4): e14235, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34378839

RESUMO

BACKGROUND: Gastroparesis is a severe diabetes complication characterized by delayed gastric emptying. We examined patients with symptoms of diabetic gastroparesis using gastric emptying scintigraphy and ultrasound drink test. The primary aim was to investigate how ultrasound could provide information about gastric motility features in diabetic gastroparesis. MATERIAL AND METHODS: We prospectively included 58 patients with diabetes (48 type 1) with symptoms of gastroparesis and 30 healthy controls. Patients were examined with ultrasound of the stomach in a seated position after drinking 500 ml low-caloric meat soup, at the same time recording dyspeptic symptoms. The following day, they were examined with gastric emptying scintigraphy, defining gastroparesis as >10% retention after 4 h. KEY RESULTS: We found motility disturbances in the proximal stomach measured by ultrasound in patients with diabetic gastroparesis. A linear mixed effects model including repeated ultrasound measurements revealed a slower decrease of the proximal stomach size in gastroparesis compared to healthy controls (p < 0.01), and the proximal diameter at 20 min was correlated to scintigraphy at 4 h (r = 0.510, p = 0.001). The antrum in patients with diabetic gastroparesis was twice as large compared to healthy controls (p = 0.009), and fasting antral size was correlated to gastric emptying scintigraphy (r = 0.329, p = 0.013). Both diabetes patients with and without gastroparesis had impaired accommodation (p = 0.011). CONCLUSIONS AND INFERENCES: On ultrasound, we found delayed reduction of proximal stomach size and impaired accommodation after a liquid meal in patients with gastroparesis, emphasizing the role of the proximal stomach. Furthermore, we found antral distention in gastroparesis patients.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Gastroparesia , Esvaziamento Gástrico , Gastroparesia/diagnóstico por imagem , Gastroparesia/etiologia , Humanos , Cintilografia , Ultrassonografia/efeitos adversos
6.
Curr Diabetes Rev ; 18(5): e220321192412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34225633

RESUMO

Autonomic neuropathy in patients with diabetes mellitus, and especially complications related to gastrointestinal neuropathy, are often overlooked in the clinic. Diabetic gastroenteropathy affects every segment of the gastrointestinal tract and generates symptoms that may include nausea, early satiety, vomiting, abdominal pain, constipation, and diarrhea. Severe cases can be complicated by weight loss, dehydration, and electrolyte disturbances. The pathophysiology is complex, the diagnostics and treatment options are multidisciplinary, and there is generally a lack of evidence for the treatment options. The aims for this review are first to summarize the pathophysiology and describe possible and expected symptoms and complications.Further, we will try to supply the clinician with a straightforward tool for diagnostics, and then, we shall summarize established treatment options, including diet recommendations, pharmacological and non-pharmacological options. Finally, we will explore the multiple possibilities of novel treatment, looking at medications related to the pathophysiology of neuropathy, other manifestations of autonomic neuropathies, and symptomatic treatment for other gastrointestinal disorders, also including new knowledge of endosurgical and neuromodulatory treatment. The overall goal is to increase awareness and knowledge on this frequent diabetic complication and to provide better tools for diagnosis and treatment. Ultimately, we hope to encourage further research in this field, as there are clear shortcomings in terms of biomarkers, pathophysiology, as well as treatment possibilities. In conclusion, diagnosis and management of diabetic gastroenteropathy are challenging and often require multidisciplinary teams and multimodal therapies. Treatment options are sparse, but new pharmacological, endoscopic, and neuromodulatory techniques have shown promising results in initial studies.


Assuntos
Doenças do Sistema Nervoso Autônomo , Complicações do Diabetes , Diabetes Mellitus , Neuropatias Diabéticas , Gastroenteropatias , Doenças do Sistema Nervoso Autônomo/diagnóstico , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/terapia , Complicações do Diabetes/complicações , Complicações do Diabetes/terapia , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/terapia , Gastroenteropatias/diagnóstico , Gastroenteropatias/etiologia , Gastroenteropatias/terapia , Humanos
7.
United European Gastroenterol J ; 9(10): 1168-1177, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34687494

RESUMO

BACKGROUND: Diabetic constipation is traditionally attributed to slow colonic transit, despite limited evidence. More than half of patients find treatment unsatisfactory. To improve treatment, there is a need for better diagnostic understanding of the condition. OBJECTIVE: In this wireless motility capsule study, we aimed to investigate gastrointestinal transit and contractility in diabetes patients with and without constipation, and in healthy controls. METHODS: We prospectively included type 1 or type 2 diabetes patients with gastrointestinal symptoms. Based on the Gastrointestinal Symptom Rating Scale we distinguished into two groups: with constipation and without constipation. Non-diabetic controls were asymptomatic. All were examined with wireless motility capsule, determining transit times and contractility parameters. RESULTS: 57 patients (42 women, 46 with type 1 diabetes) and 26 healthy controls (14 women) were included. We found no difference in transit times between diabetes patients with and without constipation. Compared to healthy controls (35:55, h:min), whole-gut transit was slower in both diabetes patients with constipation (66:15, p = 0.03) and without constipation (71:16, p < 0.001). Small bowel motility index correlated rs  = -0.32 (p = 0.01) with constipation symptoms. CONCLUSIONS: Diabetes patients with constipation had similar transit times as those without constipation. Both groups had slower whole-gut transit than healthy controls. Constipation was associated with reduced small bowel, but not colonic contractility. Our results imply that other mechanisms than slow colonic transit may be more important in the pathogenesis of diabetic constipation.


Assuntos
Endoscopia por Cápsula , Constipação Intestinal/diagnóstico , Complicações do Diabetes/fisiopatologia , Adulto , Estudos de Casos e Controles , Constipação Intestinal/fisiopatologia , Estudos Transversais , Feminino , Motilidade Gastrointestinal/fisiologia , Trânsito Gastrointestinal/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Intern Med ; 290(6): 1206-1218, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34089624

RESUMO

BACKGROUND: Chronic diarrhoea is a common, but poorly investigated diabetes complication. Autonomic neuropathy is a leading pathophysiological theory founded on old, small studies. Studies of gastrointestinal motility and pH levels are lacking. OBJECTIVES: Using new diagnostic methods, we aimed to find out if diabetic diarrhoea was associated with alterations in gastrointestinal motility, pH levels and autonomic function. METHODS: Fifty-seven patients (42 women, 46 with type 1 diabetes) were prospectively included. Symptoms were evaluated with the gastrointestinal symptom rating scale, defining ≥4 points as cases with diarrhoea. Patients scoring <4 were used as controls. We used the wireless motility capsule to measure gastrointestinal transit times, pH levels and contractility parameters. Autonomic function was assessed by measuring heart rate variability, baroreflex sensitivity and orthostatic hypotension. RESULTS: Seventeen patients (30%) had diarrhoea. Compared with controls, cases had slower gastric emptying (21:46 vs. 4:14, h:min, p = 0.03) and faster colonic transit (18:37 vs. 54:25, p < 0.001). Cases had increased intraluminal pH in the antrum (2.4 vs. 1.2, p = 0.009), caecum (7.3 vs. 6.4, p = 0.008) and entire colon (7.1 vs. 6.7, p = 0.05). They also had a decreased pH difference across the pylorus (3.3 vs. 4.9, p = 0.004) and ileocaecal junction (0.6 vs 1.0, p = 0.009). The groups did not differ in autonomic function, but diastolic blood pressure drop correlated rs = -0.34 (p = 0.04) with colonic transit time. CONCLUSIONS: Patients with diabetic diarrhoea had altered gastrointestinal transit and intraluminal pH levels, but minimal changes in autonomic function. Our results suggest that tests of gastrointestinal function are clinically useful in diabetic diarrhoea.


Assuntos
Diabetes Mellitus Tipo 1 , Neuropatias Diabéticas , Diarreia , Motilidade Gastrointestinal , Sistema Nervoso Autônomo/fisiopatologia , Diabetes Mellitus Tipo 1/complicações , Neuropatias Diabéticas/diagnóstico , Diarreia/etiologia , Feminino , Trânsito Gastrointestinal , Humanos , Concentração de Íons de Hidrogênio , Masculino , Estudos Prospectivos
9.
Clin Exp Gastroenterol ; 14: 133-144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953592

RESUMO

OBJECTIVE: Gastric emptying measurements are mandatory in gastroparesis diagnostics, but the association between delayed emptying and symptoms is questionable. It is imperative to find biomarkers better correlated to symptom generation. Hence, we examined the association between symptom severity and gastrointestinal motility measured by wireless motility capsule. PATIENTS AND METHODS: In this prospective single-centre study, patients with gastroparesis symptoms were simultaneously investigated with gastric emptying scintigraphy and wireless motility capsule, measuring regional transit times and contractility parameters. Symptom severity was assessed with the Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM), including the Gastroparesis Cardinal Symptom Index (GCSI). RESULTS: We included 107 patients (70% women). In the whole patient group, nausea correlated with the gastric (rs = -0.31, p = 0.007), small bowel (rs = -0.41, p < 0.001) and colonic (rs = -0.33, p = 0.012) motility indices. In patients with idiopathic etiology, nausea correlated with small bowel motility index (rs = -0.81, p < 0.001) and mean stomach pressure (rs = -0.64, p = 0.013). We also found negative correlations between total GCSI score and maximum pressure of the small bowel (rs = -0.77, p < 0.001) and colon (rs = -0.74, p = 0.002). In diabetes patients, total PAGI-SYM score correlated with colonic motility index (rs = -0.34, p = 0.012), and mean pressure of the colon correlated with upper abdominal pain (rs = -0.37, p = 0.007). We found no association between symptoms, gastric emptying nor any other transit times. CONCLUSION: In patients with gastroparesis symptoms, we found that symptom severity was associated with intestinal hypomotility. Based on these results, gastroparesis diagnostics should also include an evaluation of the small bowel and colon.

10.
Ecotoxicol Environ Saf ; 216: 112178, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33812211

RESUMO

Adaptation of the nematode Caenorhabditis elegans towards NM300K silver nanoparticles (Ag NPs) has previously been demonstrated. In the current study, the sensitivity to a range of secondary stressors (CeO2 NP, Ce3+, Cu2+, Cd2+, and Paraquat) following the multigenerational exposure to silver nanoparticles (Ag NPs NM300K) or AgNO3 was investigated. This revealed improved tolerance to the ROS inducer Paraquat with higher fecundity after pre-exposure to Ag NP, indicating an involvement of reactive oxygen species (ROS) metabolism in the adaptive response to NM300K. The potential contribution of the antioxidant defenses related to adaptive responses was investigated across six generations of exposure using the sod-1::GFP reporter (GA508), and the Grx1-roGFP2 (GRX) biosensor strains. Results showed an increase in sod-1 expression by the F3 generation, accompanied by a reduction of GSSG/GSH ratios, from both AgNO3 and Ag NP exposures. Continuous exposure to AgNO3 and Ag NP until the F6 generation resulted in a decreased sod-1 expression, with a concomitant increase in GSSG/GSH ratios. The results thus show that despite an initial enhancement, the continuous exposure to Ag caused a severe impairment of the antioxidant defense capacity in C. elegans.

11.
Sci Rep ; 11(1): 3795, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589735

RESUMO

Nosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13ß) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13ß were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13ß was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13ß represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.


Assuntos
Bacteriocinas/farmacologia , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/química , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Egito , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/patogenicidade , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/patogenicidade , Microbiologia de Alimentos , Humanos , Testes de Sensibilidade Microbiana
12.
Sci Rep ; 11(1): 4142, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602989

RESUMO

Gamma radiation produces DNA instability and impaired phenotype. Previously, we observed negative effects on phenotype, DNA methylation, and gene expression profiles, in offspring of zebrafish exposed to gamma radiation during gametogenesis. We hypothesize that previously observed effects are accompanied with changes in the expression profile of non-coding RNAs, inherited by next generations. Non-coding RNA expression profile was analysed in F1 offspring (5.5 h post-fertilization) by high-throughput sequencing 1 year after parental irradiation (8.7 mGy/h, 5.2 Gy total dose). Using our previous F1-γ genome-wide gene expression data (GSE98539), hundreds of mRNAs were predicted as targets of differentially expressed (DE) miRNAs, involved in pathways such as insulin receptor, NFkB and PTEN signalling, linking to apoptosis and cancer. snRNAs belonging to the five major spliceosomal snRNAs were down-regulated in the F1-γ group, Indicating transcriptional and post-transcriptional alterations. In addition, DEpiRNA clusters were associated to 9 transposable elements (TEs) (LTR, LINE, and TIR) (p = 0.0024), probable as a response to the activation of these TEs. Moreover, the expression of the lincRNAs malat-1, and several others was altered in the offspring F1, in concordance with previously observed phenotypical alterations. In conclusion, our results demonstrate diverse gamma radiation-induced alterations in the ncRNA profiles of F1 offspring observable 1 year after parental irradiation.


Assuntos
Raios gama/efeitos adversos , RNA não Traduzido/genética , Peixe-Zebra/genética , Animais , Dano ao DNA/genética , Dano ao DNA/efeitos da radiação , Metilação de DNA/genética , Metilação de DNA/efeitos da radiação , Gametogênese/genética , Gametogênese/efeitos da radiação , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Transcriptoma/genética , Transcriptoma/efeitos da radiação
13.
Sci Rep ; 11(1): 2218, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500447

RESUMO

We present here the earliest evidence for large-scale table olive production from the mid-7th millennium BP inundated site of Hishuley Carmel on the northern Mediterranean coast of Israel. Olive pit size and fragmentation patterns, pollen as well as the architecture of installations associated with pits from this site, were compared to finds from the nearby and slightly earlier submerged Kfar Samir site. Results indicate that at Kfar Samir olive oil was extracted, while at Hishuley Carmel the data showed that large quantities of table olives, the oldest reported to date, were prepared. This process was most probably facilitated by the site's proximity to the Mediterranean Sea, which served as a source of both sea water and salt required for debittering/pickling/salting the fruit, as experimentally demonstrated in this study. Comparison of pit morphometry from modern cultivars, wild-growing trees and the archaeological sites, intimates that in pit morphology the ancient pits resemble wild olives, but we cannot totally exclude the possibility that they derive from early cultivated trees. Our findings demonstrate that in this region, olive oil production may have predated table olive preparation, with each development serving as a milestone in the early exploitation of the olive.

14.
Braz J Microbiol ; 51(4): 1527-1538, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32542423

RESUMO

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by prokaryotes. Here, the molecular characterization of aureocin 4181, a bacteriocin produced by Staphylococcus aureus 4181, a strain involved in bovine mastitis, is presented. Aureocin 4181 gene cluster (aurRID1CBAT) was mined from scaffold 15 of the draft genome of its producer strain. Three (AurABC) out of the four structural peptides of aureocin 4181 are identical to those of aureocin A70, except for AurD1 of aureocin 4181, which showed a conservative substitution of Leu29 to Phe29 when compared to AurD of aureocin A70. According to molecular mass determination and peptide sequencing, combined with genome sequencing data, aureocin 4181 is an N-formylated variant of aureocin A70. The analysis of its antimicrobial spectrum was extended to include strains of the two major contagious pathogens involved in bovine mastitis, S. aureus and Streptococcus agalactiae. Aureocin 4181 exhibited a striking activity against S. aureus, inhibiting most strains tested. Besides having a broader spectrum of activity, aureocin 4181 exhibited a stronger bacteriolytic action against the target strains and proved to be from two- to fourfold more active than aureocin A70 against S. aureus. Aureocin 4181 has potential to become an alternative drug for prevention and control of mastitic staphylococci, a pathogen that imposes a huge economic burden to dairy industry worldwide. It also represents the third four-component bacteriocin described in the literature, the second in staphylococci.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Mastite Bovina/microbiologia , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Brasil , Bovinos , Feminino , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo
15.
Sci Total Environ ; 721: 137665, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32169641

RESUMO

The current study provides an in vivo analysis of the production of reactive oxygen species (ROS) and oxidative stress in the nematode Caenorhabditis elegans following exposure to EU reference silver nanoparticles NM300K and AgNO3. Induction of antioxidant defenses was measured through the application of a SOD-1 reporter, and the HyPer and GRX biosensor strains to monitor changes in the cellular redox state. Both forms of Ag resulted in an increase in sod-1 expression, elevated H2O2 levels and an imbalance in the cellular GSSG/GSH redox status. Microscopy analysis of the strains revealed that AgNO3 induced ROS-related effects in multiple tissues, including the pharynx, intestinal cells and muscle tissues. In contrast, NM300K resulted in localized ROS production and oxidative stress, specifically in tissues surrounding the intestinal lumen. This indicates that Ag from AgNO3 exposure was readily transported across the whole body, while Ag or ROS from NM300K exposure was predominantly confined within the luminal tissues. Concentrations resulting in an increase in ROS production and changes in GSSG/GSH ratio were in line with the levels associated with observed physiological toxic effects. However, sod-1 was not induced at the lowest Ag concentrations, although reprotoxicity was seen at these levels. While both forms of Ag caused oxidative stress, impaired development, and reprotoxicity, the results suggest different involvement of ROS production to the toxic effects of AgNO3versus NM300K.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Caenorhabditis elegans , Peróxido de Hidrogênio , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio , Nitrato de Prata
16.
Sci Total Environ ; 717: 137068, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062256

RESUMO

Robust biomarkers of exposure to chronic low dose stressors such as ionizing radiation, particularly following chronic low doses and dose-rates, are urgently needed. MicroRNAs (miRNA) have emerged as promising markers of exposure to high dose and dose-rate. Here, we evaluated the feasibility of classifying γ-radiation exposure at different dose rates based on miRNA expression levels. Our objective was to identify miRNA-signatures discriminating between exposure to γ-radiation or not, including exposure to chronic low dose rates. We exposed male CBA/CaOlaHsd and C57BL/6NHsd wild-type mice to 0, 2.5, 10 and 100 mGy/h γ-irradiation (3 Gy total-dose). From an initial screening of 576 miRNAs, a set of 21 signature-miRNAs was identified based on differential expression (>± 2-fold or p < 0.05). This 21-signature miRNA panel was investigated in 39 samples from 4/5 livers/group/mouse strain. A set of significantly differentially expressed miRNAs was identified in all γ-irradiated samples. Most miRNAs were upregulated in all γ-irradiated groups compared to control, and functional analysis of these miRNAs revealed involvement in several cancer-related signaling pathways. To identify miRNAs that distinguished exposed mice from controls, nine prediction methods; i.e., six variants of generalized regression models, random-forest, boosted-tree and nearest-shrunken-centroid (PAM) were used. The generalized regression methods seem to outperform the other prediction methods for classification of irradiated and control samples. Using the 21-miRNA panel in the prediction models, we identified sets of candidate miRNA-markers that predict exposure to γ-radiation. Among the top10 miRNA predictors, contributing most in each of the three γ-irradiated groups, three miRNA predictors (miR-140-3p, miR-133a-5p and miR-145a-5p) were common. Three miRNAs, miR-188-3p/26a-5p/26b-5p, were specific for lower dose-rate γ-radiation. Similarly, exposure to the high dose-rates was also correctly predicted, including mice exposed to X-rays. Our approach identifying miRNA-based signature panels may be extended to classify exposure to environmental, nutritional and life-style-related stressors, including chronic low-stress scenarios.


Assuntos
MicroRNAs/genética , Exposição à Radiação , Animais , Biomarcadores , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA
17.
Folia Morphol (Warsz) ; 79(4): 720-735, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31930468

RESUMO

BACKGROUND: The aim of the study was to investigate the ability of a combination of bone marrow mesenchymal stem cells (BM-MSCs) with and without demineralised freeze-dried bone allografts (DFDBAs) to induce bone regeneration in calvarial defects in ovariectomised rats. MATERIALS AND METHODS: Critical size defects were filled with a combination of DFDBAs and BM-MSCs or BM-MSCs alone. Eight weeks after calvarial surgery, the rats were sacrificed. The samples were analysed histologically and immunohistochemically. RESULTS: No difference was observed in vascularisation between groups C1 (animals with cranial defect only, control group) and O1 (animals with cranial defect only, ovariectomy group). Intramembranous ossification was observed at a limited level in groups C2 (animals with cranial defect with MSCs, control group) and O2 (animals with cranial defect with MSCs, ovariectomy group) compared to C1 and O1. In group C3 (animals with DFDBAs with MSCs, control group), the fibrous structures of the matrix became compact as a result of a bone graft having been placed in the cavity, but in group O3 (animals with DFDBAs with MSCs, ovariectomy group), the fibrous tissue was poorly distributed between the bone grafts for the most parts. CONCLUSIONS: We conclude that the insertion of BM-MSCs enhances bone healing; however, the DFDBA/BM-MSC combination has little effect on overcoming impaired bone formation in ovariectomised rats.


Assuntos
Células-Tronco Mesenquimais , Aloenxertos , Animais , Regeneração Óssea , Feminino , Osteogênese , Ratos
18.
Neurogastroenterol Motil ; 32(4): e13771, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31886950

RESUMO

BACKGROUND: Gastroparesis is a potentially severe late complication of diabetes mellitus. Today, delayed gastric emptying (GE) is mandatory for establishing the diagnosis. In this study, we compared wireless motility capsule (WMC) with gastric emptying scintigraphy (GES). METHODS: Seventy-two patients (49 women) with diabetes mellitus (59 type 1) and symptoms compatible with gastroparesis were prospectively included between 2014 and 2018. Patients were simultaneously examined with GES and WMC. Symptoms were assessed with the Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM) questionnaire. All patients were on intravenous glucose-insulin infusion during testing. KEY RESULTS: WMC and GES correlated r = .74, P < .001. Compared to GES, WMC at ordinary cutoff for delayed GE (300 minutes) had a sensitivity of 0.92, specificity 0.73, accuracy 0.80, and Cohen's kappa κ = 0.61 (P < .001). By receiver operating characteristics (ROC), the area under the curve was 0.95 (P < .001). A cutoff value for delayed GE of 385 minutes produced sensitivity 0.92, specificity 0.83, accuracy 0.86, and Cohen's kappa κ = 0.72 (P < .001). Inter-rater reliability for GE time with WMC was r = .996, κ = 0.97, both P < .001. There was no difference in symptom severity between patients with normal and delayed GE. CONCLUSIONS & INFERENCES: Our findings demonstrate the applicability of WMC as a reliable test to assess gastric emptying in diabetic gastroparesis showing very high inter-observer correlation. By elevating the cutoff value for delayed emptying from 300 to 385 minutes, we found higher specificity without reducing sensitivity.


Assuntos
Endoscopia por Cápsula/métodos , Complicações do Diabetes/diagnóstico , Gastroparesia/diagnóstico , Gastroparesia/etiologia , Cintilografia/métodos , Adulto , Idoso , Feminino , Esvaziamento Gástrico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Planta ; 250(5): 1567-1590, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31372744

RESUMO

MAIN CONCLUSION: Persistent DNA damage in gamma-exposed Norway spruce, Scots pine and Arabidopsis thaliana, but persistent adverse effects at the organismal and cellular level in the conifers only. Gamma radiation emitted from natural and anthropogenic sources may have strong negative impact on plants, especially at high dose rates. Although previous studies implied different sensitivity among species, information from comparative studies under standardized conditions is scarce. In this study, sensitivity to gamma radiation was compared in young seedlings of the conifers Scots pine and Norway spruce and the herbaceous Arabidopsis thaliana by exposure to 60Co gamma dose rates of 1-540 mGy h-1 for 144 h, as well as 360 h for A. thaliana. Consistent with slightly less prominent shoot apical meristem, in the conifers growth was significantly inhibited with increasing dose rate ≥ 40 mGy h-1. Post-irradiation, the conifers showed dose-rate-dependent inhibition of needle and root development consistent with increasingly disorganized apical meristems with increasing dose rate, visible damage and mortality after exposure to ≥ 40 mGy h-1. Regardless of gamma duration, A. thaliana showed no visible or histological damage or mortality, only delayed lateral root development after ≥ 100 mGy h-1 and slightly, but transiently delayed post-irradiation reproductive development after ≥ 400 mGy h-1. In all species dose-rate-dependent DNA damage occurred following ≥ 1-10 mGy h-1 and was still at a similar level at day 44 post-irradiation. In conclusion, the persistent DNA damage (possible genomic instability) following gamma exposure in all species may suggest that DNA repair is not necessarily mobilized more extensively in A. thaliana than in Norway spruce and Scots pine, and the far higher sensitivity at the organismal and cellular level in the conifers indicates lower tolerance to DNA damage than in A. thaliana.


Assuntos
Arabidopsis/efeitos da radiação , Raios gama/efeitos adversos , Picea/efeitos da radiação , Pinus sylvestris/efeitos da radiação , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Noruega , Picea/genética , Picea/crescimento & desenvolvimento , Pinus sylvestris/genética , Pinus sylvestris/crescimento & desenvolvimento , Plântula/genética , Plântula/efeitos da radiação
20.
Photochem Photobiol Sci ; 18(8): 1945-1962, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31305802

RESUMO

Exposure to ambient UV-B radiation may prime protective responses towards various stressors in plants, though information about interactive effects of UV-B and gamma radiation is scarce. Here, we aimed to test whether UV-B exposure could prime acclimatisation mechanisms contributing to tolerance to low-moderate gamma radiation levels in Scots pine seedlings, and concurrently whether simultaneous UV-B and gamma exposure may have an additive adverse effect on seedlings that had previously not encountered either of these stressors. Responses to simultaneous UV-B (0.35 W m-2) and gamma radiation (10.2-125 mGy h-1) for 6 days with or without UV-B pre-exposure (0.35 W m-2, 4 days) were studied across various levels of organisation, as compared to effects of either radiation type. In contrast to UV-B, and regardless of UV-B presence, gamma radiation at ≥42.9 mGy h-1 caused increased formation of reactive oxygen species and reduced shoot length, and reduced root length at 125 mGy h-1. In all experiments there was a gamma dose rate-dependent increase in DNA damage at ≥10.8 mGy h-1, generally with additional UV-B-induced damage. Gamma-induced growth inhibition and gamma- and UV-B-induced DNA damage were still visible 44 days post-irradiation, even at 20.7 mGy h-1, probably due to genomic instability, but this was reversed after 8 months. In conclusion, there was no evidence of a protective effect of UV-B on gamma-induced growth inhibition and DNA damage in Scots pine, and no additive adverse effect of gamma and UV-B radiation on growth in spite of the additional UV-B-induced DNA damage.


Assuntos
Raios gama , Pinus sylvestris/crescimento & desenvolvimento , Pinus sylvestris/efeitos da radiação , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Raios Ultravioleta
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