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1.
Environ Sci Technol ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317381

RESUMO

Ammonium-related pathways are important for groundwater arsenic (As) enrichment, especially via microbial Fe(III) reduction coupled with anaerobic ammonium oxidation; however, the key pathways (and microorganisms) underpinning ammonium-induced Fe(III) reduction and their contributions to As mobilization in groundwater are still unknown. To address this gap, aquifer sediments hosting high As groundwater from the western Hetao Basin were incubated with 15N-labeled ammonium and external organic carbon sources (including glucose, lactate, and lactate/acetate). Decreases in ammonium concentrations were positively correlated with increases in the total produced Fe(II) (Fe(II)tot) and released As. The molar ratios of Fe(II)tot to oxidized ammonium ranged from 3.1 to 3.7 for all incubations, and the δ15N values of N2 from the headspace increased in 15N-labeled ammonium-treated series, suggesting N2 as the key end product of ammonium oxidation. The addition of ammonium increased the As release by 16.1% to 49.6%, which was more pronounced when copresented with organic electron donors. Genome-resolved metagenomic analyses (326 good-quality MAGs) suggested that ammonium-induced Fe(III) reduction in this system required syntrophic metabolic interactions between bacterial Fe(III) reduction and archaeal ammonium oxidation. The current results highlight the significance of syntrophic ammonium-stimulated Fe(III) reduction in driving As mobilization, which is underestimated in high As groundwater.

2.
Environ Sci Technol ; 56(14): 10105-10119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35763428

RESUMO

High-arsenic (As) groundwaters, a worldwide issue, are critically controlled by multiple interconnected biogeochemical processes. However, there is limited information on the complex biogeochemical interaction networks that cause groundwater As enrichment in aquifer systems. The western Hetao basin was selected as a study area to address this knowledge gap, offering an aquifer system where groundwater flows from an oxidizing proximal fan (low dissolved As) to a reducing flat plain (high dissolved As). The key microbial interaction networks underpinning the biogeochemical pathways responsible for As mobilization along the groundwater flow path were characterized by genome-resolved metagenomic analysis. Genes associated with microbial Fe(II) oxidation and dissimilatory nitrate reduction were noted in the proximal fan, suggesting the importance of nitrate-dependent Fe(II) oxidation in immobilizing As. However, genes catalyzing microbial Fe(III) reduction (omcS) and As(V) detoxification (arsC) were highlighted in groundwater samples downgradient flow path, inferring that reductive dissolution of As-bearing Fe(III) (oxyhydr)oxides mobilized As(V), followed by enzymatic reduction to As(III). Genes associated with ammonium oxidation (hzsABC and hdh) were also positively correlated with Fe(III) reduction (omcS), suggesting a role for the Feammox process in driving As mobilization. The current study illustrates how genomic sequencing tools can help dissect complex biogeochemical systems, and strengthen biogeochemical models that capture key aspects of groundwater As enrichment.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/química , Compostos Férricos/metabolismo , Compostos Ferrosos , Água Subterrânea/química , Nitratos/análise , Oxirredução , Poluentes Químicos da Água/química
3.
Environ Sci Technol ; 55(22): 15181-15195, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34706533

RESUMO

Biogeochemical processes critically control the groundwater arsenic (As) enrichment; however, the key active As-mobilizing biogeochemical processes and associated microbes in high dissolved As and sulfate aquifers are poorly understood. To address this issue, the groundwater-sediment geochemistry, total and active microbial communities, and their potential functions in the groundwater-sediment microbiota from the western Hetao basin were determined using 16S rRNA gene (rDNA) and associated 16S rRNA (rRNA) sequencing. The relative abundances of either sediment or groundwater total and active microbial communities were positively correlated. Interestingly, groundwater active microbial communities were mainly associated with ammonium and sulfide, while sediment active communities were highly related to water-extractable nitrate. Both sediment-sourced and groundwater-sourced active microorganisms (rRNA/rDNA ratios > 1) noted Fe(III)-reducers (induced by ammonium oxidation) and As(V)-reducers, emphasizing the As mobilization via Fe(III) and/or As(V) reduction. Moreover, active cryptic sulfur cycling between groundwater and sediments was implicated in affecting As mobilization. Sediment-sourced active microorganisms were potentially involved in anaerobic pyrite oxidation (driven by denitrification), while groundwater-sourced organisms were associated with sulfur disproportionation and sulfate reduction. This study provides an extended whole-picture concept model of active As-N-S-Fe biogeochemical processes affecting As mobilization in high dissolved As and sulfate aquifers.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , DNA , Compostos Férricos , Sedimentos Geológicos , RNA Ribossômico 16S/genética , Poluentes Químicos da Água/análise
4.
Int J Syst Evol Microbiol ; 69(12): 3666-3671, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29580368

RESUMO

Strain NB2006T was isolated from an isosaccharinate-degrading, nitrate-reducing enrichment culture in minimal freshwater medium at pH 10. Analysis of the 16S rRNA gene sequence indicated that this strain was most closely related to species of the newly established genus Anaerobacillus. This was supported by phenotypic and metabolic characterisation that showed that NB2006T was rod-shaped, Gram-stain-positive, motile and formed endospores. It was an aerotolerant anaerobe and an obligate alkaliphile that grew at pH 8.5-11, could tolerate up to 6 % (w/v) NaCl, and grew at a temperature between 10 and 40 °C. In addition, it could utilise a number of organic substrates, and was able to reduce nitrate and arsenate. The predominant cellular fatty acids were C16 : 0, C16 : 1ω11c, anteiso-C15 : 0, iso-C15 : 0, C16 : 1ω7c/iso-C15 : 0 2-OH and C14 : 0. The cell wall peptidoglycan contained meso-diaminopimelic acid and the DNA G+C content was 37.7 mol%. In silico DNA-DNA hybridization with the four known species of the genus Anaerobacillus showed 21.8, 21.9, 22.4, and 21.5 % relatedness to Anaerobacillusarseniciselenatis DSM 15340T, Anaerobacilus alkalidiazotrophicus DSM 22531T, Anaerobacillusalkalilacustris DSM 18345T, and Anaerobacillus macyae DSM 16346T, respectively. NB2006T differed from strains of other species of the genus Anaerobacillus in its ability to metabolise isosaccharinate, an alkaline hydrolysis product of cellulose. On the basis of the consensus of phylogenetic and phenotypic analyses, this strain represents a novel species of the genus Anaerobacillus, for which the name Anaerobacillus isosaccharinicus sp. nov. is proposed. The type strain is NB2006T (=DSM 100644T=LMG 30032T).


Assuntos
Bacillaceae/classificação , Filogenia , Açúcares Ácidos/metabolismo , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
J Clin Dent ; 27(3): 71-75, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28390200

RESUMO

OBJECTIVES: The purpose of this study was to determine the safety and plaque-reducing effectiveness of a newly designed manual toothbrush compared to that of a leading marketed toothbrush and a reference standard manual toothbrush control. METHODS: This examiner-blind, randomized, single-use study used a cross-over design. Sixty-eight qualifying male and female subjects were randomly assigned either an Arm & Hammer™ Truly Radiant™ Deep Clean manual toothbrush (TR), a Colgate® Extra Clean manual toothbrush (C), or an ADA reference standard manual toothbrush (SM) according to one of three computer-generated sequences. Following instruction in the use of their assigned brush, subjects brushed at home with a standard fluoride toothpaste twice daily for two minutes during a one-week familiarization period. At the end of this period, the subjects returned to the study site after refraining from oral hygiene for 12-16 hours and from eating and drinking for four hours. Plaque was disclosed and scored using the Rustogi Modification of the Navy Plaque Index (RMNPI). Subjects brushed under supervision with their assigned toothbrush for two minutes in a room without mirrors and apart from the dental examiner, after which plaque was disclosed and rescored. They were then given one of the alternate toothbrushes according to their assigned sequence, and the familiarization routine and evaluations were repeated until each of the subjects used each of the three brushes. Within-treatment and between-treatment whole mouth RMNPI scores and scores at each of twelve subsets of sites were analyzed using paired t-tests and appropriate ANCOVA models, respectively. RESULTS: Within-group analyses showed that all three toothbrushes produced statistically significant reductions from the pre-brushing baseline in whole mouth RMNPI scores (p < 0.0001), with respective reductions of 68.2%, 58.3%, and 48.5% for TR, C, and SM. Between-group analyses showed that TR was significantly more effective (p < 0.0001) than C and SM with 16.4% and 40.3% greater reductions in whole mouth scores, respectively. TR also produced statistically significant greater reductions (p < 0.0001) than the other two manual brushes at each of the twelve subsets of sites examined, with the greatest differences at the lingual and gingival sites, especially sites presenting difficulty in access, such as those in the posterior lingual gingival region. CONCLUSIONS: While all three manual toothbrushes produced significant supragingival plaque reductions with a single use, the Truly Radiant Deep Clean brush was significantly more effective than the Colgate Extra Clean and ADA manual brushes in reducing wholemouth plaque, as well as plaque at all subsets of sites analyzed including difficult-to-reach areas.


Assuntos
Índice de Placa Dentária , Placa Dentária/terapia , Escovação Dentária , Adulto , Estudos Cross-Over , Desenho de Equipamento , Feminino , Humanos , Masculino , Método Simples-Cego
6.
Harmful Algae ; 137: 102654, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39003020

RESUMO

Microbial blooms have been reported in the First Generation Magnox Storage Pond at the Sellafield Nuclear Facility. The pond is kept alkaline with NaOH to minimise fuel rod corrosion, however alkali-tolerant microbial blooms dominated by the cyanobacterium Pseudanabaena catenata are able to thrive in this hostile environment. This study assessed the impact of alternative alkali-dosing regimens (KOH versus NaOH treatment) on biomass accumulation, using a P. catenata dominated mixed culture, which is representative of the pond environment. Optical density was reduced by 40-67 % with KOH treatment over the 3-month chemostat experiment. Microbial community analysis and proteomics demonstrated that the KOH-dependent inhibition of cell growth was mostly specific to P. catenata. The addition of KOH to nuclear storage ponds may therefore help control growth of this pioneer photosynthetic organism due to its sensitivity to potassium, while maintaining the high pH needed to inhibit the corrosion of stored nuclear fuel.


Assuntos
Cianobactérias , Lagoas , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/metabolismo , Cianobactérias/fisiologia , Lagoas/microbiologia , Compostos de Potássio/farmacologia , Hidróxidos/farmacologia , Potássio/metabolismo , Potássio/análise , Biomassa
7.
Cureus ; 16(4): e58583, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38765364

RESUMO

Background Hallux rigidus (HR) is the most common arthritic condition of the foot. Although first metatarsophalangeal joint (MTPJ) arthrodesis has been the historical gold-standard treatment, polyvinyl alcohol (PVA) hydrogel implants have gained popularity as a joint-sparing technique. However, recent studies have shown variable failure rates of PVA hydrogel implants. The purpose of this study was to report the five-year experience with PVA hydrogel implants performed by a single surgeon. Methodology Health records were queried from August 2016 to 2021 for patients who underwent primary PVA hydrogel implant hemiarthroplasty for symptomatic late-stage HR. Patient demographics and postoperative outcomes variables were evaluated. Kaplan-Meier analysis was used to evaluate implant survival. A total of 146 PVA hydrogel implant procedures were performed with a minimum six-month follow-up. Results The majority of patients were female (n = 103, 70.5%), with a mean age of 58.1 (±10.1) years, body mass index of 27.3 (±5.2) kg/m2, and American Society of Anesthesiologists score <3 (n = 131, 89.7%). The majority had stage II or III disease (n = 115, 78.8%). Patients experienced significant improvement in visual analog scale score (p < 0.0001) and hallux dorsiflexion (p = 0.0005). There were 22 (15.1%) complications, including implant subsidence (n = 15, 10.3%), deep infection (n = 6, 4.1%), and hypertrophic ossification (n = 1, 0.7%). Revision surgeries were required in 12.3% (n = 18) of patients at an average of 9.4 (±9.2) months postoperatively. This included nine (6.2%) revision PVA hydrogel implant procedures and nine (6.2%) first MTJP arthrodesis. The one- and two-year survival rates for MTPJ arthrodesis (n = 9) were 95.9% and 86.3%, respectively. Conclusions In the largest single-surgeon series reported, first MTPJ hemiarthroplasty with a PVA hydrogel implant significantly improved pain and hallux dorsiflexion at an average of 14.5 months postoperatively. There was a high two-year survivorship of 86.3% until failure which required first MTPJ arthrodesis. Future studies should be performed to refine the indications for PVA hydrogel implants and identify risk factors.

8.
Sci Rep ; 14(1): 10840, 2024 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735998

RESUMO

This study aimed to assess the knowledge regarding impacts, causes and management of black triangles (BT) among participants from different educational backgrounds including dental students, dentists and laypeople. This descriptive cross-sectional observational research included 435 participants who comprised 4 groups: pre-clinical (3rd year) dental students, clinical (4th and 5th year) dental students, dentists, and laypeople. A constructed self-reported questionnaire was utilized to assess participants' demographic data and their knowledge of the impacts, causes and management of BT. The VAS scale was used to assess participants' ratings for the impacts of BT on esthetics, with 0 meaning no impact and 10 meaning very severe negative impacts. The most reported treatments for BT were "cannot be treated" 99.3% and "non-surgical periodontal treatment" 67.1%. Meanwhile, the least reported was "modify the porcelain" 41.8%. The most reported cause of BT was "periodontal disease" 85.1%. However, the least reported were "parafunction" and "deep implants" 33.1% each. Dental professionals had better knowledge of the causes (t = 8.189, P < 0.001) and management (t = 8.289, P < 0.001) of BT than the non-dental participants. The dentists had the best knowledge, while the laypeople had the least knowledge of the causes (F = 62.056, P < 0.001) and treatment (F = 46.120, P < 0.001) of BT. The knowledge of the causes (t = 0.616, P = 0.538) and treatment (t = 1.113, P = 0.266) for BT was not significantly different between males and females. Age was not significantly related to the total knowledge about the causes (r = -0.034, P = 0.475) or treatment (r = -0.034, P = 0.482) for BT. Dental professionals had better knowledge of the impacts, causes and management of BT than the non-dental participants. The dentists were the best, while the laypeople were the worst in this regard. Age and gender had no relationships with the knowledge of causes or management of BT.


Assuntos
Odontólogos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Feminino , Odontólogos/psicologia , Adulto , Estudos Transversais , Inquéritos e Questionários , Estudantes de Odontologia/psicologia , Adulto Jovem , Pessoa de Meia-Idade
9.
Sci Rep ; 14(1): 5675, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454057

RESUMO

This analytical cross-sectional study evaluated the perception of black triangles (BT) and examined the relationships between the perception of BT, personality factors, different educational backgrounds and demographic factors. 435 participants were included and divided into four groups: dentists, clinical (4th and 5th year) dental students, pre-clinical (3rd year) dental students, and laypeople. Participants' perception of the attractiveness of smile profiles of maxillary and mandibular anterior dentition with BT was rated using a ten-point VAS scale with 0 being the least, and 10 being the most attractive smile profile. The personality was assessed using the NEO-FFI personality questionnaire. The smile profile with multiple large BT was rated the least attractive for the maxillary (mean = 3.6) and mandibular (mean = 3.9) tested profiles. The smile profile without BT was rated the most attractive for the maxillary (mean = 9.1) and mandibular (mean = 8.8) tested profiles. The dental professionals perceived the maxillary smile profile with multiple large BT as less attractive than the non-dental participants (t = - 2.715, P = 0.007). Being a male, having dental education, having lower Neuroticism scores, as well as having higher Openness, Agreeableness, Conscientiousness, and Extraversion scores predicted and contributed more towards perceiving various tested smile profiles as more attractive. These findings show that black triangles negatively impacts the perception of smile attractiveness, and that personality traits and having dental education impact the perception of smile attractiveness for smiles with black triangles.


Assuntos
Personalidade , Sorriso , Humanos , Masculino , Estudos Transversais , Escolaridade , Percepção , Atitude do Pessoal de Saúde
10.
Ann Dermatol Venereol ; 140(10): 614-8, 2013 Oct.
Artigo em Francês | MEDLINE | ID: mdl-24090891

RESUMO

BACKGROUND: Herein we report a case of cat scratch disease on account of its atypical presentation. PATIENTS AND METHODS: A 21-year-old woman presented erythema nodosum associated with painful bilateral inguinal adenopathy, odynophagia, joint pain and evening urticaria in a setting of impaired general condition. Initial serological testing for Bartonella henselae was negative. PCR for Bartonella henselae performed on an adenectomy fragment was positive. A favourable outcome was achieved with azithromycin. COMMENTS: This case shows an atypical and severe presentation of cat scratch disease and raises the problem of sensitivity of serotyping.


Assuntos
Infecções por Bartonella/diagnóstico , Eritema Nodoso/etiologia , Animais , Antibacterianos/uso terapêutico , Artralgia/etiologia , Azitromicina/uso terapêutico , Infecções por Bartonella/complicações , Infecções por Bartonella/microbiologia , Bartonella henselae/isolamento & purificação , Gatos , Feminino , Humanos , Cetoprofeno/uso terapêutico , Linfonodos/microbiologia , Doenças Linfáticas/etiologia , Doenças Linfáticas/microbiologia , Faringite/etiologia , Pristinamicina/uso terapêutico , Urticária/etiologia , Infecção dos Ferimentos/microbiologia , Adulto Jovem
11.
Sci Total Environ ; 858(Pt 3): 160066, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356776

RESUMO

Sulfide-induced reduction (sulfidization) of arsenic (As)-bearing Fe(III) (oxyhydro)oxides may lead to As mobilization in aquifer systems. However, little is known about the relative contributions of sulfidization and non-sulfidization of Fe(III) (oxyhydro)oxides reduction to As mobilization. To address this issue, high As groundwater with low sulfide (LS) and high sulfide (HS) concentrations were pumped through As(V)-bearing ferrihydrite-coated sand columns (LS-column and HS-column, respectively) being settled within wells in the western Hetao Basin, China. Sulfidization of As(V)-bearing ferrihydrite was evidenced by the increase in dissolved Fe(II) and the presence of solid Fe(II) and elemental sulfur (S0) in both the columns. A conceptual model was built using accumulated S0 and Fe(II) produced in the columns to calculate the proportions of sulfidization-induced Fe(III) (oxyhydro)oxide reduction and non-sulfidization-induced Fe(III) (oxyhydro)oxide reduction. Fe(III) reduction via sulfidization occurred preferentially in the inlet ends (LS-column, 31 %; HS-column, 86 %), while Fe(III) reduction via non-sulfidization processes predominated in the outlet ends (LS-column, 96 %; HS-column, 86 %), and was attributed to the metabolism of genera associated with Fe(III) reduction (including Shewanella, Ferribacterium, and Desulfuromonas). Arsenic was mobilized in the columns via sulfidization and non-sulfidization processes. More As was released from the solid of the HS-column than that of the LS-column due to the higher intensity of sulfidization in the presence of higher concentrations of dissolved S(-II). Overall, this study highlights the sulfidization of As-bearing Fe(III) (oxyhydro)oxides as an important As-mobilizing pathway in complex As-Fe-S bio-hydrogeochemical networks.


Assuntos
Arsênio , Compostos Férricos , Areia , Sulfetos , Óxidos , Compostos Ferrosos
12.
Cureus ; 15(10): e46469, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37927717

RESUMO

Cardiovascular disease (CVD) stands as a global health crisis, with its complex web of conditions, including coronary artery disease, heart failure, hypertension, and stroke, continuing to exact a heavy toll on individuals and healthcare systems worldwide. Despite substantial advances in medical technology and pharmaceutical interventions, CVD remains a formidable adversary, necessitating innovative prevention, management, and rehabilitation approaches. In tracing the historical trajectory of CVD, the narrative reveals the antiquated practices of early 20th-century medicine, marked by extended bed rest as the primary modality for heart-related conditions. It underscores the critical juncture when exercise was first recognized as a therapeutic tool for cardiac health, setting the stage for the evolution of cardiac rehabilitation (CR). CR programs have transcended their initial focus on exercise, expanding to encompass dietary guidance, psychosocial support, and comprehensive risk factor modification. These holistic interventions enhance physical recovery and address the psychosocial and lifestyle aspects of CVD management, ultimately improving patients' overall well-being. CR programs increasingly leverage advanced technologies and personalized strategies to tailor interventions to individual patient needs, ultimately enhancing outcomes and reducing the burden of CVD. In conclusion, this narrative review illuminates the transformative journey of cardiac care, with a particular spotlight on the indispensable role of CR in reshaping the landscape of cardiovascular medicine. By evolving from historical practices to comprehensive, patient-centered interventions, CR has made significant strides in improving the prognosis, quality of life, and holistic well-being of individuals grappling with the complexities of CVD. Understanding this historical context and the contemporary advancements is paramount for healthcare professionals and policymakers as they navigate the intricate terrain of cardiovascular medicine and endeavor to mitigate the impact of this pervasive disease.

13.
Eur J Nucl Med Mol Imaging ; 39(8): 1266-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22526961

RESUMO

PURPOSE: To compare the sensitivity of (123)I-metaiodobenzylguanidine (MIBG) SPECT and (68)Ga-DOTATATE PET/CT in detecting phaeochromocytomas (PCC) and paragangliomas (PGL) in the initial diagnosis and follow-up of patients with PCC and PGL disease. METHODS: Retrospective analysis of 15 patients with PCC/PGL who had contemporaneous (123)I-MIBG and (68)Ga-DOTATATE imaging. RESULTS: Of the 15 patients in the series, 8 were concordant with both modalities picking up clinically significant lesions. There were no patients in whom both modalities failed to pick up clinically significant lesions. There was discordance in seven patients: 5 had positive (68)Ga-DOTATATE and negative (123)I-MIBG, and 2 (12 and 14) had negative (68)Ga-DOTATATE and positive (123)I-MIBG. Utilizing (123)I-MIBG as the gold standard, (68)Ga-DOTATATE had a sensitivity of 80 % and a positive predictive value of 62 %. The greatest discordance was in head and neck lesions, with the lesions in 4 patients being picked up by (68)Ga-DOTATATE and missed by (123)I-MIBG. On a per-lesion analysis, cross-sectional (CT and MRI) and (68)Ga-DOTATATE was superior to (123)I-MIBG in detecting lesions in all anatomical locations, and particularly bony lesions. CONCLUSION: First, (68)Ga-DOTATATE should be considered as a first-line investigation in patients at high risk of PGL and metastatic disease, such as in the screening of carriers for mutations associated with familial PGL syndromes. Second, if (123)I-MIBG does not detect lesions in patients with a high pretest probability of PCC or PGL, (68)Ga-DOTATATE should be considered as the next investigation. Third, (68)Ga-DOTATATE hould be considered in preference to (123)I-MIBG in patients in whom metastatic spread, particularly to the bone, is suspected.


Assuntos
3-Iodobenzilguanidina , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Imagem Multimodal/métodos , Compostos Organometálicos , Paraganglioma/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
14.
Eur J Neurol ; 19(2): 241-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21771201

RESUMO

BACKGROUND AND PURPOSE: Fibroblast growth factor-2 (FGF-2) and platelet-derived growth factor-A (PDGF-AA) are potent modulators of oligodendrocytes, the main responsible cells for myelin regeneration. We measured FGF-2 and PDGF-AA in the sera and cerebrospinal fluid (CSF) of patients with relapsing-remitting multiple sclerosis (RR-MS) and compared these values with control subjects. METHODS: Twenty-three patients with RR-MS and 23 subjects without inflammatory and demyelinating diseases were included. Serum samples of the patients were collected in both relapse and remission phases and were analyzed with ELISA method. CSF was drawn during the relapse period. Blood and CSF were drawn from control subjects for comparison. Wilcoxon and Mann-Whitney U-test and Spearman's rank correlation were used for analysis. P values of <0.05 were considered significant. RESULTS: Age and sex distribution were similar in both groups. Serum values of FGF-2 were higher in relapse phase compared with remission phase, with a trend toward significance (P=0.052). CSF PDGF-AA showed significant negative correlation with disease duration (correlation coefficient=-0.58, P=0.004). Serum levels of PDGF did not differ between two phases significantly. There was no difference in serum and CSF values of these factors between patients and controls. When we compared patients with prolonged disease with controls, a significant difference between the CSF levels of PDGF-AA was observed (mean±SEM 2.78±0.8 in controls vs. 0.55±0.29 in patients with MS≥2 years, P<0.05). CONCLUSION: Our study was the first to show that CSF PDGF-AA is related to disease duration. Supporting previous findings we showed that serum and CSF levels of these factors are weak indicators of disease severity.


Assuntos
Fator 2 de Crescimento de Fibroblastos/metabolismo , Esclerose Múltipla Recidivante-Remitente/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Feminino , Fator 2 de Crescimento de Fibroblastos/sangue , Fator 2 de Crescimento de Fibroblastos/líquido cefalorraquidiano , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Fator de Crescimento Derivado de Plaquetas/líquido cefalorraquidiano , Índice de Gravidade de Doença
15.
J Exp Med ; 157(2): 591-9, 1983 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-6337230

RESUMO

The attributes of the test grafts with which putatively tolerant rats are challenged influence their immune response. Lewis (Lew) rats inoculated at birth with Lew/BN F1 hybrid bone marrow cells accept large skin allografts more readily than small allografts, and F1 hybrid skin grafts survive better than BN transplants. The results indicate that the survivals of these major histocompatibility complex-incompatible grafts are determined by the same factors that operate when only weak histoincompatibilities prevail.


Assuntos
Mecanismo Genético de Compensação de Dose , Sobrevivência de Enxerto , Tolerância Imunológica , Transplante de Pele , Animais , Animais Recém-Nascidos , Feminino , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Fatores de Tempo
16.
J Endocrinol Invest ; 33(1): 54-60, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19820296

RESUMO

Endocrine tumors comprise a range of benign and malignant conditions that produce a spectrum of clinical symptoms and signs depending on the specific hormones they produce. The symptoms and presentations of these tumors are often independent of their size and location. Because of their expression of cell membrane receptors or production of specific types of hormones or peptides, endocrine tumors can be identified with functional radionuclide imaging much more readily compared to standard cross-sectional imaging. In recent years, 18F-fluoro-deoxy- D-glucose positron emission tomography (18F-FDG-PET) has emerged as a useful tool for diagnosing and assessing many tumors. In this review we describe how PET, using 18F-FDG and other radiopharmaceuticals can be useful in the diagnosis and management of a wide range of endocrine tumors.


Assuntos
Neoplasias das Glândulas Endócrinas/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Medula Suprarrenal/metabolismo , Carcinoma Neuroendócrino/diagnóstico por imagem , Catecolaminas , Síndrome de Cushing/etiologia , Fluordesoxiglucose F18 , Humanos , Compostos Organometálicos , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Receptores de Somatostatina/análise , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
17.
FEMS Microbiol Ecol ; 96(7)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32459307

RESUMO

Intermediate-level radioactive waste includes cellulosic materials, which under the hyperalkaline conditions expected in a cementitious geological disposal facility (GDF) will undergo abiotic hydrolysis forming a variety of soluble organic species. Isosaccharinic acid (ISA) is a notable hydrolysis product, being a strong metal complexant that may enhance the transport of radionuclides to the biosphere. This study showed that irradiation with 1 MGy of γ-radiation under hyperalkaline conditions enhanced the rate of ISA production from the alkali hydrolysis of cellulose, indicating that radionuclide mobilisation to the biosphere may occur faster than previously anticipated. However, irradiation also made the cellulose fibres more available for microbial degradation and fermentation of the degradation products, producing acidity that inhibited ISA production via alkali hydrolysis. The production of hydrogen gas as a fermentation product was noted, and this was associated with a substantial increase in the relative abundance of hydrogen-oxidising bacteria. Taken together, these results expand our conceptual understanding of the mechanisms involved in ISA production, accumulation and biodegradation in a biogeochemically active cementitious GDF.


Assuntos
Celulose , Resíduos Radioativos , Bactérias/genética , Biodegradação Ambiental , Hidrólise
18.
Environ Int ; 136: 105489, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31991235

RESUMO

Various functional groups of microorganisms and related biogeochemical processes are likely to control arsenic (As) mobilization in groundwater systems. However, spatially-dependent correlations between microbial community composition and geochemical zonation along groundwater flow paths are not fully understood, especially with respect to arsenic mobility. The western Hetao Basin was selected as the study area to address this limitation, where groundwater flows from a proximal fan (geochemical-group I: low As, oxidizing), through a transition area (geochemical-group II: moderate As, moderately-reducing) and then to a flat plain (geochemical-group III: high As, reducing). High-throughput Illumina 16S rRNA gene sequencing showed that the microbial community structure in the proximal fan included bacteria affiliated with organic carbon degradation and nitrate-reduction or even nitrate-dependant Fe(II)-oxidation, mainly resulting in As immobilization. In contrast, for the flat plain, high As groundwater contained Fe(III)- and As(V)-reducing bacteria, consistent with current models on As mobilization driven via reductive dissolution of Fe(III)/As(V) mineral assemblages. However, Spearman correlations between hydrogeochemical data and microbial community compositions indicated that ammonium as a possible electron donor induced reduction of Fe oxide minerals, suggesting a wider range of metabolic pathways (including ammonium oxidation coupled with Fe(III) reduction) driving As mobilization in high As groundwater systems.


Assuntos
Compostos de Amônio , Arsênio , Água Subterrânea , Microbiota , Poluentes Químicos da Água , Elétrons , Compostos Férricos , Sedimentos Geológicos , RNA Ribossômico 16S
19.
Anaesthesia ; 64(1): 39-42, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19087004

RESUMO

We retrospectively reviewed 60 normal magnetic resonance imaging scans to assess the anatomical shape of the thecal sac at the L3/4 and L4/5 vertebral interspaces. In all cases the thecal sac was oval at L3/4 but in 26 (43%; 95% CI 31-55%) the thecal sac changed from oval at the L3/4 interspace to triangular at L4/5 (with the apex of the triangle presenting to the posterior epidural space). We propose that this anatomical variant would make it more difficult to obtain cerebrospinal fluid at the lower level, as a slightly lateral approach could lead to identification of the epidural space but failure to puncture the thecal sac. This may offer an explanation for a 'dry tap' when a lower interspace is chosen.


Assuntos
Vértebras Lombares/anatomia & histologia , Adolescente , Adulto , Dura-Máter , Espaço Epidural/anatomia & histologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Canal Medular/anatomia & histologia , Medula Espinal/anatomia & histologia , Adulto Jovem
20.
Diabetes Metab Syndr ; 13(3): 1911-1915, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31235114

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that is associated with an increased the risk of metabolic syndrome (MetS) and hence increased cardiovascular diseases in women. This systematic review and meta-analysis aimed at examining the prevalence of MetS in Iranian women with PCOS. This was a systematic review and meta-analysis of English and Persian studies, using the following keywords: Polycystic Ovary Syndrome, Hyperandrogenism, Metabolic Syndrome,"MetSyn", X Syndrome, and Iran in several national and international databases (Scientific Information Database (SID), Magiran, Web of Science, Google Scholar, PubMed, and Scopus from inception to February 2019. Heterogeneity among the studies was assessed using the Cochran's Q test. The random effects model was then used to estimate the overall prevalence of MetS. ALL the analyses were performed using STATA, version 12. Overall, 10 studies were included in the study. The overall prevalence of MetS among Iranian women with PCOS was 26.6% (95% CI: 16.60-31.70). In addition, the mean body mass index (BMI) was 27.47 (95% CI: 25.46-29.48) and the mean waist circumference was 87.94 (95% CI: 84.28-91.60). According the meta-regression results, there were no significant associations between the prevalence of MetS and sample size, year of publication, waist circumference, BMI, and age. One-fourth of Iranian women with PCOS have MetS. Given the overlap between anthropometric and metabolic abnormalities in PCOS and the features of MetS, accurate identification of patients with MetS is important to ensure early diagnosis and subsequent interventions to effectively manage the condition.


Assuntos
Síndrome Metabólica/epidemiologia , Síndrome do Ovário Policístico/complicações , Índice de Massa Corporal , Feminino , Humanos , Resistência à Insulina , Irã (Geográfico)/epidemiologia , Síndrome Metabólica/etiologia , Prevalência , Circunferência da Cintura
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