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For many years, the recombination of excited ions of argon, Ar+(P1/22), has been assumed negligible under ambient conditions as compared to the recombination of ground-state ions, Ar+(P3/22). This opinion was confronted with detailed experimental results that seem to clearly support it. Here, we propose a new interpretation in light of our recent calculations, which shows that the recombination efficiency is comparable for both fine-structure states. Noteworthily, in our model leading to a picture consistent with the experiment, residual dimer ions emerge from Ar+(P1/22) due to non-adiabatic dynamics effects and interplay in measured data.
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PURPOSE: PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients. METHODS: Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes. RESULTS: Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean -4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement). CONCLUSION: Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.
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Síndrome de Klippel-Trenaunay-Weber , Syzygium , Adulto , Humanos , Imidazóis , Mutação , Oxazepinas , Fosfatidilinositol 3-Quinases/genética , Qualidade de VidaRESUMO
INTRODUCTION: Viral hepatitis represents a serious public health problem in the world especially in the Maghreb where the prevalence of the 5 viruses A, B, C, D, and E remains high and varies from one Maghreb country to another, there is few published studies on these infections in our Maghreb countries. METHOD OF STUDY: Our work is a review of the literature about prevalence, the most common mode of transmission, and the most exposed population for these viruses in the Maghreb countries through published studies between 2011 and 2017. RESULT: It has been found that the Maghreb countries are endemic for the five viruses with variable prevalence from one country to another, with sometimes heterogeneous data in the same country. For hepatitis B, Mauritania is the Maghreb country most affected by this infection unlike the rest of the Maghreb countries which are moderately endemic for this virus, the lowest prevalence of VHB was noted in Morocco, the genotype the most common is the D for the majority of Maghreb countries, and the precore mutant profile is also the most common. For hepatitis C the prevalence of infection does not vary much from one Maghreb country to another, but it remains slightly higher in Mauritania. The population most exposed to the virus C in the five countries is hemodialysis patients. The most common genotype in all Maghreb countries is genotype 1 except for Libya, where genotype 4 remains the most common probably related to its borders with Egypt. For hepatitis D, Mauritania is the only Maghreb country with a high endemicity for the virus. Tunisia has the lowest prevalence for hepatitis A and E compared to the rest of the Maghreb countries, all of which are endemic for these two viruses with fecal-oral transmission. CONCLUSION: The management of these viral hepatitis is costly for the health economy and to reduce their prevalence, prevention measures must be followed like vaccination and improving hygiene conditions.
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Hepatite Viral Humana/epidemiologia , África do Norte/epidemiologia , Argélia/epidemiologia , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/terapia , Hepatite Viral Humana/virologia , Humanos , Líbia/epidemiologia , Mauritânia/epidemiologia , Marrocos/epidemiologia , Prevalência , Tunísia/epidemiologiaRESUMO
INTRODUCTION: This study aims to assess the effectiveness of triptorelin on lower urinary tract symptoms (LUTS) in Algerian patients with non-localized prostate cancer in routine practice. MATERIALS: This prospective, observational, non-interventional, multicentre study was conducted in Algeria. Included patients who had locally advanced or metastatic prostate cancer and were treated with triptorelin 11.25mg given every 12 weeks. LUTS were evaluated with the International Prostate Symptom Score (IPSS) until week 48 after treatment initiation. An IPSS>7 indicated moderate to severe LUTS. The primary objective of the study was to determine the distribution of IPSS at week 48. RESULTS: This study enrolled 193 patients at 21 centres. A total of 144 participants had IPSS available at baseline and after baseline (136 patients had moderate to severe LUTS and eight had mild LUTS at baseline). At week 48, amongst the 116 patients with IPSS available and moderate to severe LUTS at baseline, 94 (81.0%) had moderate to severe LUTS and 22 (19.0%) had mild LUTS. At week 48, the eight patients with mild symptoms at baseline remained in this category. The proportion of patient with severe LUTS decreased from 53.7% at baseline to 12.1% at week 48. Adverse events were reported in 22.9% of participants. CONCLUSION: A reduction of LUTS is observed in patients with locally advanced or metastatic prostate cancer treated with triptorelin in routine practice. This is in agreement with similar observational studies of triptorelin conducted in other countries. LEVEL OF PROOF: 4.
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Sintomas do Trato Urinário Inferior/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Pamoato de Triptorrelina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Argélia , Progressão da Doença , Humanos , Injeções Intramusculares , Sintomas do Trato Urinário Inferior/etiologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Atenção Primária à Saúde/estatística & dados numéricos , Neoplasias da Próstata/complicações , Resultado do Tratamento , Pamoato de Triptorrelina/administração & dosagemRESUMO
The efficiency of two mycorrhizal bio-inoculants on the mineral uptake during the growth stages of a Mediterranean forage legume sulla (Hedysarum coronarium L.) was studied in the field on a highly calcareous soil. The first inoculum (Mm) was made up of a mixture of native arbuscular mycorrhizal fungi (AMF) isolated from calcareous soils: Septoglomus constrictum, Funneliformis geosporum, Glomus fuegianum, Rhizophagus irregularis and Glomus sp. The second was a commercial inoculum (Mi) containing one AMF species: R. irregularis. Both mycorrhizal inoculants increased total and arbuscular colonization of sulla roots. Inoculation with Mm showed a positive effect on sulla shoot dry weight (SDW) when compared to Mi and non-inoculated plants (control). Mineral contents (P, Mg, Mn, Fe) were higher in the shoots of sulla plants cultivated on mycorrhiza-inoculated plots compared to non-inoculated ones. This enhancement was observed during the flowering stage for P, Mg and Mn and during the rosette stage for Fe. An increase in P content of 50 % in plants inoculated with Mm compared to non-inoculated ones may be explained by the induction of root alkaline and acid phosphatase activities. Higher efficiency of native AMF species adapted to calcareous soils opens the way towards the development of mycorrhiza bio-fertilizers targeted to improve sustainable fertilization management in such soils.
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Fabaceae/metabolismo , Fabaceae/microbiologia , Minerais/metabolismo , Micorrizas/fisiologia , Microbiologia do Solo , Solo/química , Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Ativação Enzimática , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/metabolismo , Brotos de Planta/microbiologiaRESUMO
AIMS: Estimate the prevalence of symptoms suggestive of overactive bladder (OAB) in women living in the Middle East to describe their demographic characteristics and explore treatment-seeking behavior. METHODS: Cross-sectional, population-based survey of women aged ≥ 40 years resident in Algeria, Jordan, Lebanon or Egypt. Respondents were recruited using computer-assisted telephone interview over approximately 4 months. Eligible respondents were asked to complete the OAB-V8, a validated questionnaire that explores the extent of bother from the key symptoms of OAB without clinical investigations. In addition, information regarding demographics, comorbidities and treatment behavior was collected, and respondents were stratified by age. RESULTS: A total of 2297 eligible women agreed to participate. Mean age was 54 ± 10 years; over half (59.3%) were aged 40-55 years. Overall, 53.8% of eligible women had symptoms suggestive of OAB (Jordan 58.5%; Egypt 57.5%; Algeria 49.9%; Lebanon 49.0%), with over 90% also reporting symptoms of urinary incontinence. Only 13.0% of women with symptoms suggestive of OAB were currently receiving treatment, while most (74.3%) had never been treated; these data were consistent across country and age categories. Among the untreated subgroup, almost half (48.7%) reported they were 'not bothered by symptoms,' while 8.4% considered OAB to be 'part of normal aging' and 4.7% did not know it was treatable. CONCLUSION: A high prevalence of symptoms suggestive of OAB was observed, and the majority had symptoms of urinary incontinence. Despite the high prevalence, most women had never received treatment. Considering the potential significant impact of OAB symptoms on health, quality of life and productivity, these findings highlight an unmet medical need in the population studied. Strategies to improve treatment-seeking behavior (e.g., through education and tackling the stigma associated with OAB symptoms) may improve the diagnosis, management and health outcomes of women with OAB in the Middle East.
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Bexiga Urinária Hiperativa , Adulto , Argélia/epidemiologia , Estudos Transversais , Egito/epidemiologia , Feminino , Humanos , Jordânia/epidemiologia , Líbano/epidemiologia , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Inquéritos e Questionários , Bexiga Urinária Hiperativa/diagnóstico , Bexiga Urinária Hiperativa/epidemiologiaRESUMO
BACKGROUND AND OBJECTIVE: The presence of carcinoma in situ (Cis) in association with bladder cancer is associated with a poor prognosis. However, the prognosis associated with the presence of Cis in ureteral margins (CUM) during radical cystectomy has been poorly defined. To assess the prognosis associated with the presence of Cis in ureteral margins in patients with pM0 bladder cancer who have not undergone neoadjuvant chemotherapy. MATERIALS AND METHODS: A retrospective case-control study was conducted between 2001 and 2016 using data from one academic center in France. From 1,450 radical cystectomies, 122 patients (case) who had CUM were matched according to age, sex, pTNM stage and urinary diversion method with a population sample of 122 patients (controls) who did not have Cis in ureteral margins during radical cystectomy. The survival analysis was performed by Kaplan-Meier using a (95%) CI. Multivariate Cox regression analysis was used to test the effect of CUM on cancer-specific survival. Recurrence-free survival was defined as a recurrence of urothelial carcinoma in the upper urinary tract. RESULTS AND LIMITATIONS: The mean follow-up period was 55.43 ± 39.6 months. The rate of Cis in the bladder in the CUM cases group was evaluated at 11.47%. The median overall and specific survival was inferior in the CUM cases group estimated at 43.3 [35.33-56.93] months, 52.43 [42.16-68.93] months respectively compared to the control group with a significant difference (P= 0.001, P= 0.0039). The cumulative probability of urothelial recurrence-free survival was decreased in the case group compared with the control group (63.9% vs. 92.6%, Pâ¯=â¯0.0001). Multivariate analysis shown that urothelial recurrence was associated with CUM [(P <0.001), (HR adjusted =11.31), (95% CI): (3.38-37.77)] and the macroscopic appearance of the ureter (thickened, dilated) [(P= 0.003), (HR adjusted =4.62), (95% CI): (3.31-8.84)]. CONCLUSION: CUM is a poor prognostic factor that impacts cancer-specific survival and Recurrence-free survival. The presence of CUM has been independently associated with a significant increase in the risk of urothelial recurrence, and a decrease in both overall and specific survival. This supports the use of frozen section analysis to complete radical cystectomy without CUM.
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Carcinoma in Situ/patologia , Cistectomia/efeitos adversos , Margens de Excisão , Recidiva Local de Neoplasia/patologia , Ureter/patologia , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Seguimentos , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/etiologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Ureter/cirurgia , Neoplasias da Bexiga Urinária/patologiaRESUMO
BACKGROUND: Alpha-fetoprotein (AFP) is a serum tumor marker used in the past for surveillance and screening of hepatocellular carcinoma (HCC) in patients with cirrhosis. Its prognostic value is still debated in the literature. The aim of this study was to evaluate the prognostic impact of the AFP rate at diagnosis on the overall survival of patients with a small HCC (<3cm) in patients with cirrhosis. PATIENTS AND METHODS: Among the 122 patients diagnosed with HCC during the study period, 49 patients had a small HCC at diagnosis, including 40,8% (N 20) patients with a negative AFP (group I) and 59,18% (N 29) with an AFP >10 ng / ml (group II). Both groups of patients were comparable for age and WHO status (World Health Organization). Patient survival was assessed by the Kaplan-Meier method. The survival at 5 years was 35.7% in group 1 vs 12.3% in group 2. The AFP level was identified as an independent prognostic factor of survival. CONCLUSION: Alpha-fetoprotein serum positivity seems to have prognostic value in patients with single small HCC.
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Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , alfa-Fetoproteínas/metabolismo , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos RetrospectivosRESUMO
BACKGROUND AND OBJECTIVE: The presence of lysozyme in human gingiva has not previously been demonstrated. In this study, we looked for evidence for the potential role of lysozyme as a protector of gingival elastic fibres. The objective of this study was also to determine the ex vivo susceptibility to hydrolysis of gingival elastic fibres from patients with or without periodontal disease by human leukocyte elastase and by human cathepsin G. MATERIALS AND METHODS: Using gingival tissue sections from eight control, 10 gingivitis and 10 periodontitis patients, we evaluated the area fraction occupied by gingival elastic fibres (after selective staining) by the use of automated image analysis. In the ex vivo experiments, serial tissue sections from four control, four gingivitis, four young periodontitis and four aged periodontitis patients were submitted to the action of human leukocyte elastase and cathepsin G, after which enzymatic activities were determined by image analysis. Indirect immunodetection of lysozyme was also done on tissue sections for all patients included in this study. RESULTS: Large variations of the area fraction occupied by elastic fibres were observed in human gingiva from young and aged patients with and without periodontal disease. In control and gingivitis patients, leukocyte elastase and cathepsin G had high comparable elastin solubilizing activities. With young and aged periodontitis patients, the two serine proteinases had weak elastin solubilizing activities. Lysozyme appeared to be present at the periphery of gingival elastic fibres in periodontitis patients. CONCLUSION: Lysozyme can be considered an important natural protector of elastic fibres in pathological gingiva.
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Inibidores Enzimáticos/farmacologia , Gengiva/enzimologia , Gengivite/enzimologia , Muramidase/fisiologia , Periodontite/enzimologia , Adolescente , Adulto , Fatores Etários , Idoso , Catepsina G , Catepsinas/farmacologia , Proteínas Contráteis/análise , Tecido Elástico/efeitos dos fármacos , Tecido Elástico/enzimologia , Tecido Elástico/patologia , Elastina/análise , Proteínas da Matriz Extracelular/análise , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Gengiva/patologia , Hemorragia Gengival/enzimologia , Gengivite/patologia , Humanos , Hidrólise , Processamento de Imagem Assistida por Computador , Elastase de Leucócito/farmacologia , Masculino , Pessoa de Meia-Idade , Muramidase/análise , Perda da Inserção Periodontal/enzimologia , Bolsa Periodontal/enzimologia , Periodontite/patologia , Serina Endopeptidases/farmacologia , Adulto JovemRESUMO
The purpose of this in situ study is to quantify the inflammatory cell subsets and the area fraction (AA%) occupied by collagen fibers in human healthy and diseased (four different stages) gingival connective tissue in order to establish a possible correlation between periodontal disease resulting in collagen breakdown and specific inflammatory cell subsets. Paraffin gingival tissue sections from eight healthy controls (group 0), 10 patients with gingivitis (group 1), 10 patients with moderate periodontitis (group 2) and 10 patients with severe periodontitis (group 3) were immunohistochemically investigated using antibodies against CD-45+, CD-3+, CD-8+, CD-20+, CD-68+, and EMA+ (plasma cells). The AA% occupied by gingival collagen fibers significantly decreased from 54.12% in group (0) to 38.58% in group (1), to 31.87% in group (2), and to 25.46% in group (3). In progressive lesions of periodontal disease, CD-3(+) and CD-8+ cell numbers were increased in early stages within the connective tissue, while CD-20+ cell numbers were increased only in late stages. On the other hand, EMA+, CD-68+ and CD-45+ cell numbers were progressively increased from group (0) to group (3). We demonstrated that CD-68+ monocyte/macrophages, CD-45+ leukocyte common antigen and notably EMA+ plasma cells are pertinently correlated with the severity of periodontal disease and related collagen breakdown.
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Colágeno/imunologia , Macrófagos , Monócitos , Doenças Periodontais/imunologia , Doenças Periodontais/patologia , Plasmócitos , Adolescente , Adulto , Antígenos CD/análise , Antígenos CD/imunologia , Antígenos CD20/análise , Antígenos CD20/imunologia , Complexo CD3/análise , Complexo CD3/imunologia , Antígenos CD8/análise , Antígenos CD8/imunologia , Estudos de Casos e Controles , Colágeno/metabolismo , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Gengiva/química , Gengiva/imunologia , Gengiva/patologia , Gengivite/imunologia , Gengivite/metabolismo , Gengivite/patologia , Humanos , Imuno-Histoquímica , Antígenos Comuns de Leucócito/análise , Antígenos Comuns de Leucócito/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Periodontite/imunologia , Periodontite/metabolismo , Periodontite/patologia , Plasmócitos/imunologia , Plasmócitos/metabolismo , Plasmócitos/patologia , Adulto JovemRESUMO
BACKGROUND: Although its incidence has decreased over the last 20 years, gastric adenocarcinoma remains frequent (1,033,701 new cases worldwide per year, Globocan 2018). Its prognosis is still poor, with overall survival rates of 10 to 25% despite improvement in surgical and perioperative treatment. In Morocco, we do not have data on survival and predictors of mortality in our population, the present study aims to describe the epidemiological and clinicopathological features of gastric adenocarcinoma and the survival rate. MATERIALS AND METHODS: We retrospectively reviewed data files of 265 patients with histological diagnosis of gastric adenocarcinoma between January 2007 and June 2017. Survival was estimated by the Kaplan Meier method and prognostic factors in multivariate analysis (Cox model). RESULTS: The mean age of our population was 54.48 ±15.53 with a sex ratio M/F of 1.76. Clinical symptomatology dominated by epigastralgia episodes in two-thirds of the cases and deterioration of the general state in most cases (61.7%). Proximal localization accounted for 17.4%. According to histological classification, poorly differentiated adenocarcinoma was the most common histological type (51.7%). Metastatic or locally advanced tumors accounted for 92% of cases. Only 11% of patients received curative resection. The 5-year survival was 6%. Multivariate analysis revealed three prognostic factors: vascular invasion, advanced stage and differentiation. DISCUSSION: The high mortality of gastric adenocarcinoma in our Moroccan series is probably explained by the late stage at diagnosis. Symptoms are nonspecific and endoscopy is usually performed for advanced symptoms such as anemia, bleeding or weight loss. The main identified prognostic factors in gastric adenocarcinoma are tumor subtype (Linitic forms), stage at diagnosis, vascular and lymph nodes invasion and general performance status which correlates to available data in the literature. Besides, the age distribution of GC in our series showed that the proportion of affected young adult is high (30.6%) compared to data from developed countries varying between 6 and 15%. This age distribution can be explained by the Westernization of diet, the increase of obesity in our population and more exposure to alcohol and tobacco. CONCLUSION: Overall cancer survival in our population does not exceed 7%, a rate that remains low compared to studies published in the occidental literature. Recommendations have to be elaborated to make a strategy for screening and early diagnosis of gastric adenocarcinoma to improve the survival rate.
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Adenocarcinoma/epidemiologia , Neoplasias Gástricas/epidemiologia , Adenocarcinoma/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Marrocos , Neoplasias Gástricas/mortalidade , Taxa de SobrevidaRESUMO
An endemic North African Saharan plant from of the Apiaceae family, Deverra scoparia, used locally for medicinal preparations, showed a strong inhibitory effect on porcine liver carboxylesterase. The active compound from the aerial part of the plant was purified by semi-preparative HPLC and photodiode array detection, and structurally determined by (1)H, (13)C NMR and mass spectroscopy methods. This compound was identified as flavone-3,4',7-trihydroxy-3'-methoxy-7-glucoside and it was found to be a powerful competitive inhibitor of porcine liver carboxylesterase with a inhibition constant value of 16 microM. Based on the structural features of the inhibitor and the enzyme active site region, it seems that the flavonoside binds to the surface of the enzyme. The low K(i) value suggests some physiological significance of such inhibitory activity, especially concerning the bio-transformation of xenobiotics.
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Apiaceae/química , Carboxilesterase/antagonistas & inibidores , Flavonas/farmacologia , Glucosídeos/farmacologia , Fígado/enzimologia , Animais , Flavonas/química , Glucosídeos/química , Medicina Tradicional , Oriente Médio , Estrutura Molecular , SuínosRESUMO
Osteopaenia is a common complication of inflammatory bowel diseases (IBD). However, the mechanisms of bone loss are still the subject of debate. The aims of this study were to investigate bone loss in HLA-B27 transgenic rats, a spontaneous model of colitis and to compare the results provided by the usual markers of bone remodelling and by direct measurement of bone protein synthesis. Systemic inflammation was evaluated in HLA-B27 rats and control rats from 18 to 27 months of age. Then bone mineral density, femoral failure load, biochemical markers of bone remodelling and protein synthesis in tibial epiphysis were measured. Bone mineral density was lower in HLA-B27 rats than in controls. Plasma osteocalcin, a marker of bone formation, and fractional protein synthesis rate in tibial epiphysis did not differ between the two groups of rats. In contrast, urinary excretion of deoxypyridinoline, a marker of bone resorption, was significantly increased in HLA-B27 rats. The present results indicate that bone fragility occurs in HLA-B27 rats and mainly results from an increase in bone resorption. Systemic inflammation may be the major cause of the disruption in bone remodelling homeostasis observed in this experimental model of human IBD.
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Doenças Ósseas Metabólicas/etiologia , Remodelação Óssea , Antígeno HLA-B27/metabolismo , Aminoácidos/urina , Animais , Biomarcadores/sangue , Biomarcadores/urina , Densidade Óssea , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/fisiopatologia , Doenças Ósseas Metabólicas/urina , Reabsorção Óssea/complicações , Reabsorção Óssea/urina , Colite/complicações , Colite/genética , Modelos Animais de Doenças , Epífises/metabolismo , Fêmur/fisiopatologia , Antígeno HLA-B27/genética , Masculino , Osteocalcina/sangue , Osteogênese , Biossíntese de Proteínas , Ratos , Ratos Endogâmicos F344 , Ratos Transgênicos , Resistência à Tração , Tíbia/metabolismoRESUMO
Bio-based poly(l-lactide)/poly(amide-11) blends (PLA/PA11, 80/20 w/w) and poly(l-lactide)/poly(amide-6) blends (PLA/PA6, 80/20 w/w) are processed by twin-screw extrusion followed by injection-moulding and key rheological parameters controlling their morphologie are investigated. The same work is done using the same PLA modified by a multi-step reactive extrusion route with an epoxy-based chain extender to obtain modified poly(lactide)/poly(amide-11) (PLA-j/PA11 80/20 w/w) blends. The morphologies of the extruded materials and of the injection moulded parts are characterized by SEM and their formation is deeply discussed via rheological investigation to highlight the contribution of viscosity, elasticity and interfacial tension. The existence of a critical shear rate related to the transition from nodular to fibrillar morphology is highlighted and the results are in good agreement with the condition of fibrillation Ca/Ca(crit) ≥ 4. Interestingly, with the exception of PLA/PA6 specimens, all blends obviously display uniform thin-thread fibrillar morphologies after injection-moulding. Compared with pure PLA, a drastic increase of the ductility was observed in the blends exhibiting a fiberlike structure without meanwhile sacrificing the stiffness. This study confirms that, through the appropriate choice of blend components (viscosity and elasticity ratio, flow conditions, interfacial tensions) the in situ fibrillation concept provides access, at a reasonable cost, to new materials with improved thermomechanical performances, without sacrificing weight and ability to be recycled.
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We provide lithological, sedimentological and micropalaeontological descriptions of 39 sections and boreholes crossing the upper Miocene deposits of the Rifian Corridor. These deposits represent the sedimentary remnants of the marine gateway that connected the Atlantic to the Mediterranean in the late Miocene. Results from these 39 sites were adopted to reconstruct the palaeogeographic evolution of the gateway presented in the associated research article (Capella et al., 2018) [1]. For each outcrop we present a synthesis of field observations, lithofacies, key sedimentological features, planktic and benthic assemblages.
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The Saethre-Chotzen syndrome is characterized by premature fusion of cranial sutures resulting from mutations in Twist, a basic helix-loop-helix (bHLH) transcription factor. We have identified Twist target genes using human mutant calvaria osteoblastic cells from a child with Saethre-Chotzen syndrome with a Twist mutation that introduces a stop codon upstream of the bHLH domain. We observed that Twist mRNA and protein levels were reduced in mutant cells and that the Twist mutation increased cell growth in mutant osteoblasts compared with control cells. The mutation also caused increased alkaline phosphatase and type I collagen expression independently of cell growth. During in vitro osteogenesis, Twist mutant cells showed increased ability to form alkaline phosphatase-positive bone-like nodular structures associated with increased type I collagen expression. Mutant cells also showed increased collagen synthesis and matrix production when cultured in aggregates, as well as an increased capacity to form a collagenous matrix in vivo when transplanted into nude mice. In contrast, Twist mutant osteoblasts displayed a cell-autonomous reduction of osteocalcin mRNA expression in basal conditions and during osteogenesis. The data show that genetic deletion of Twist causing reduced Twist dosage increases cell growth, collagen expression, and osteogenic capability, but inhibits osteocalcin gene expression. This provides one mechanism that may contribute to the premature cranial ossification induced by deletion of the bHLH Twist domain in Saethre-Chotzen syndrome.
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Acrocefalossindactilia/genética , Proteínas Nucleares , Osteocalcina/biossíntese , Osteogênese/genética , Crânio/citologia , Fatores de Transcrição/genética , Fosfatase Alcalina/biossíntese , Antígenos de Diferenciação , Colágeno/biossíntese , Dosagem de Genes , Sequências Hélice-Alça-Hélice , Humanos , Mutação , Osteoblastos , Proteína 1 Relacionada a TwistRESUMO
An optimized Monte Carlo method based on the null collision technique and on the treatment of individual interactions is used for the simulation of the electron transport in multilayer materials from high energies (MeV or several hundred of keV) down to low cutoff energies (between 1 and 10 eV). In order to better understand the electron transport and the energy deposition at the interface in the composite application framework, two layer materials are considered (carbon and polystyrene with densities of 1.7 g cm(-3) and 1.06 g cm(-3), respectively) under two slab or three slab configurations as, e.g. a thin layer of carbon sandwiched between two polystyrene layers. The electron-matter cross-sections (electron-carbon and electron-polystyrene) used in the case of pure material (carbon and polystyrene) as well as our Monte-Carlo code have been first validated. The boundary interface layer is considered without any mean free path truncation and with a rigorous treatment of the backscattered and also the forward scattered electrons from one layer to another. The large effect of the choice of a low cutoff energy and the dissociation process consideration are also clearly shown in the heterogeneous multi-layer media more particularly on the secondary electron emission, inelastic collision number and energy spectra.
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Carbono/química , Elétrons , Modelos Químicos , Radiometria/métodos , Carbono/efeitos da radiação , Fibra de Carbono , Simulação por Computador , Transporte de Elétrons , Transferência Linear de Energia , Modelos Moleculares , Método de Monte Carlo , Doses de Radiação , Espalhamento de RadiaçãoRESUMO
The inhibitory effect of phenolic extracts of several plants from the Algerian Atlas used traditionally in Arab folk medicine was tested on the porcine kidney acylase I activity. An endemic Saharan plant of the Brassicaceae family, Oudneya africana, has shown a strong inhibitory effect. The active compound was isolated and purified by semi-preparative HPLC and HPLC-photodiode array detection, and structurally determined using 1H, 13C NMR and mass spectroscopy methods. Results indicate that maackiain 3-O-(6'-O-malonyl-beta-D-glucopyranoside) showed a competitive inhibition of porcine kidney acylase I with a Ki value of 11 microM. The malonyl moiety appeared to be a structural key element for the inhibitory activity. This observation indicates interesting structure-activity relationships for the inhibitory action of this compound on the acylase I and its potential role in the toxicity of haloalkene-derived mercapturates and that of the enzyme in detoxication and bioactivation.
Assuntos
Amidoidrolases/antagonistas & inibidores , Brassicaceae/química , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Rim/enzimologia , Pterocarpanos/isolamento & purificação , Pterocarpanos/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Cinética , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , SuínosRESUMO
The measurement of the mobility of SF-6 in the mixtures SF6 -Ar and SF6 -Xe is reported over the density-reduced electric field strength E/N 1-180 Td (1 Townsend = 10(-17) V cm(2)), from a time-resolved pulsed Townsend technique. Simultaneously, the mobility of SF-6 in the same binary mixtures has been calculated from a set of collision cross sections for SF-6 -Ar, SF-6 -Xe, and SF-6 - SF6 using a Monte Carlo simulation procedure for ion transport. The good agreement between measured and calculated mobilities in these gas mixtures has led us to conclude that the validation of our cross section sets is confirmed. The elastic collision cross section, a predominant process for ion energies lower than about 10 eV, was determined from a semiclassical JWKB approximation using a rigid core potential model for the ion-neutral systems under consideration. This elastic cross section was then added to several other inelastic collision cross sections found in the literature for ion conversion, electron detachment of SF-6 and charge transfer. Moreover, the calculations of the mobility and the ratios of the transverse and longitudinal diffusion coefficients to the mobility were extended into a much wider E/N range from 1 to 4000 Td. Additionally, we have also calculated the energy distribution functions and the reaction coefficients for ion conversion and electron detachment. Finally, we have shown that the range of validity for the calculation of the mobility in gas mixtures from Blanc's law is only valid for the low E/N region, where the interaction is dominated by elastic collisions and the ion distribution function remains essentially Maxwellian.
RESUMO
Flavonol compounds of three Mediterranean plants from the Algerian Atlas used traditionally in Arab folk medicine, Arenaria serpyllifolia, Rhamnus alaternus and Thapsia garganica, were found to inhibit the enzymatic activities of both rat intestine and purified porcine liver carboxylesterase in a concentration-dependent manner. Results indicate that the flavonol compounds from the aerial part of these plants lead to the inactivation of the CE pI = 5.1 with Ki of micromolar range. These results encourage us to perform further biological investigation.