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1.
Gastroenterology ; 167(2): 357-367.e9, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38513745

RESUMO

BACKGROUND & AIMS: There is an unmet need for noninvasive tests to improve case-finding and aid primary care professionals in referring patients at high risk of liver disease. METHODS: A metabolic dysfunction-associated fibrosis (MAF-5) score was developed and externally validated in a total of 21,797 individuals with metabolic dysfunction in population-based (National Health and Nutrition Examination Survey 2017-2020, National Health and Nutrition Examination Survey III, and Rotterdam Study) and hospital-based (from Antwerp and Bogota) cohorts. Fibrosis was defined as liver stiffness ≥8.0 kPa. Diagnostic accuracy was compared with FIB-4, nonalcoholic fatty liver disease fibrosis score (NFS), LiverRisk score and steatosis-associated fibrosis estimator (SAFE). MAF-5 was externally validated with liver stiffness measurement ≥8.0 kPa, with shear-wave elastography ≥7.5 kPa, and biopsy-proven steatotic liver disease according to Metavir and Nonalcoholic Steatohepatitis Clinical Research Network scores, and was tested for prognostic performance (all-cause mortality). RESULTS: The MAF-5 score comprised waist circumference, body mass index (calculated as kg / m2), diabetes, aspartate aminotransferase, and platelets. With this score, 60.9% was predicted at low, 14.1% at intermediate, and 24.9% at high risk of fibrosis. The observed prevalence was 3.3%, 7.9%, and 28.1%, respectively. The area under the receiver operator curve of MAF-5 (0.81) was significantly higher than FIB-4 (0.61), and outperformed the FIB-4 among young people (negative predictive value [NPV], 99%; area under the curve [AUC], 0.86 vs NPV, 94%; AUC, 0.51) and older adults (NPV, 94%; AUC, 0.75 vs NPV, 88%; AUC, 0.55). MAF-5 showed excellent performance to detect liver stiffness measurement ≥12 kPa (AUC, 0.86 training; AUC, 0.85 validation) and good performance in detecting liver stiffness and biopsy-proven liver fibrosis among the external validation cohorts. MAF-5 score >1 was associated with increased risk of all-cause mortality in (un)adjusted models (adjusted hazard ratio, 1.59; 95% CI, 1.47-1.73). CONCLUSIONS: The MAF-5 score is a validated, age-independent, inexpensive referral tool to identify individuals at high risk of liver fibrosis and all-cause mortality in primary care populations, using simple variables.


Assuntos
Técnicas de Imagem por Elasticidade , Cirrose Hepática , Valor Preditivo dos Testes , Humanos , Masculino , Feminino , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Cirrose Hepática/patologia , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Medição de Risco , Idoso , Prognóstico , Índice de Massa Corporal , Fatores de Risco , Circunferência da Cintura , Inquéritos Nutricionais , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Adulto , Aspartato Aminotransferases/sangue , Contagem de Plaquetas , Fígado/patologia , Fígado/diagnóstico por imagem , Países Baixos/epidemiologia , Biópsia , Curva ROC , Reprodutibilidade dos Testes
2.
Genet Med ; 26(6): 101105, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38430071

RESUMO

PURPOSE: To describe a recessively inherited cerebral small vessel disease, caused by loss-of-function variants in Nitrilase1 (NIT1). METHODS: We performed exome sequencing, brain magnetic resonance imaging, neuropathology, electron microscopy, western blotting, and transcriptomic and metabolic analyses in 7 NIT1-small vessel disease patients from 5 unrelated pedigrees. RESULTS: The first identified patients were 3 siblings, compound heterozygous for the NIT1 c.727C>T; (p.Arg243Trp) variant and the NIT1 c.198_199del; p.(Ala68∗) variant. The 4 additional patients were single cases from 4 unrelated pedigrees and were all homozygous for the NIT1 c.727C>T; p.(Arg243Trp) variant. Patients presented in mid-adulthood with movement disorders. All patients had striking abnormalities on brain magnetic resonance imaging, with numerous and massively dilated basal ganglia perivascular spaces. Three patients had non-lobar intracerebral hemorrhage between age 45 and 60, which was fatal in 2 cases. Western blotting on patient fibroblasts showed absence of NIT1 protein, and metabolic analysis in urine confirmed loss of NIT1 enzymatic function. Brain autopsy revealed large electron-dense deposits in the vessel walls of small and medium sized cerebral arteries. CONCLUSION: NIT1-small vessel disease is a novel, autosomal recessively inherited cerebral small vessel disease characterized by a triad of movement disorders, massively dilated basal ganglia perivascular spaces, and intracerebral hemorrhage.


Assuntos
Hemorragia Cerebral , Doenças de Pequenos Vasos Cerebrais , Transtornos dos Movimentos , Linhagem , Humanos , Feminino , Masculino , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/patologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Pessoa de Meia-Idade , Hemorragia Cerebral/genética , Hemorragia Cerebral/patologia , Hemorragia Cerebral/diagnóstico por imagem , Transtornos dos Movimentos/genética , Transtornos dos Movimentos/patologia , Transtornos dos Movimentos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Alelos , Adulto , Idoso , Sistema Glinfático/patologia , Sistema Glinfático/diagnóstico por imagem , Sequenciamento do Exoma , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Aminoidrolases/genética
3.
Scand J Gastroenterol ; 59(6): 737-741, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563432

RESUMO

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver condition worldwide. There is an urgent need to develop new biomarkers to assess disease severity and to define patients with a progressive phenotype. Activin A is a new promising biomarker with conflicting results about liver fibrosis. In this study we investigate levels of Activin A in patients with biopsy proven MASLD. We assess levels of Activin A in regard to fibrosis stage and genetic variant I148M in the patatin-like phospholipase domain-containing protein 3 (PNPLA3). METHODS: Activin A levels were assessed in plasma samples from patients with biopsy-proven MASLD in a cross-sectional study. All patients were clinically evaluated and the PNPLA3 I148M genotype of the cohort was assessed. FINDINGS: 41 patients were included and 27% of these had advanced fibrosis. In MASLD patients with advanced fibrosis, Activin A levels was higher (p < 0.001) and could classify advanced fibrosis with an AUROC for activin A of 0.836 (p < 0.001). Patients homozygous for PNPLA3 I148M G/G had higher levels of activin A than non-homozygotes (p = 0.027). CONCLUSIONS: Circulating activin A levels were associated with advanced fibrosis and could be a potential blood biomarker for identifying advanced fibrosis in MASLD. Patients with the risk genotype PNPLA3 I148M G/G had higher levels of activin A proposing activin A as a contributor of the transition from simple steatosis to a fibrotic phenotype.


Assuntos
Ativinas , Biomarcadores , Fígado Gorduroso , Lipase , Cirrose Hepática , Proteínas de Membrana , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/sangue , Feminino , Pessoa de Meia-Idade , Lipase/genética , Lipase/sangue , Cirrose Hepática/genética , Cirrose Hepática/sangue , Estudos Transversais , Ativinas/sangue , Ativinas/genética , Biomarcadores/sangue , Adulto , Fígado Gorduroso/genética , Fígado Gorduroso/sangue , Fígado Gorduroso/patologia , Idoso , Genótipo , Fígado/patologia , Índice de Gravidade de Doença , Aciltransferases , Fosfolipases A2 Independentes de Cálcio
4.
Clin Gastroenterol Hepatol ; 21(1): 90-102.e6, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35074532

RESUMO

BACKGROUND & AIMS: The effect of race on routinely available noninvasive tests of fibrosis is incompletely understood. This study evaluated the performance of noninvasive tests among white and Asian patients in the STELLAR trials (NCT03053050 and NCT03053063), which evaluated selonsertib in patients with advanced (F3-F4) fibrosis due to nonalcoholic steatohepatitis (NASH). METHODS: Baseline liver biopsies were centrally read using the NASH Clinical Research Network system, and 4 noninvasive tests (Nonalcoholic fatty liver disease fibrosis score [NFS], Fibrosis-4 index [FIB-4], Enhanced Liver Fibrosis test [ELF], and liver stiffness by vibration-controlled transient elastography) were measured. The performance of these tests to discriminate advanced fibrosis was evaluated using areas under the receiver operating characteristics curves with 5-fold cross-validation repeated 100 times. RESULTS: Among 3207 patients screened with evaluable liver histology, 2281 were whites and 762 were Asians. Seventy-two percent of whites and 67% of Asians had advanced fibrosis. The areas under the receiver operating characteristics curves of the noninvasive tests for advanced fibrosis were similar in whites and Asians: 0.73 and 0.75 for NFS, 0.78 and 0.80 for FIB-4, 0.79 and 0.81 for ELF, and 0.80 and 0.83 for liver stiffness, respectively. At the published cutoffs, the tests had similar sensitivities and specificities in the 2 groups. However, the sensitivities of NFS, FIB-4, and ELF were low in both white and Asian patients younger than 40 years. CONCLUSIONS: In the global phase III STELLAR trials, the diagnostic performance of routinely available noninvasive tests for the detection of advanced fibrosis due to NASH was acceptable and similar between white and Asian patients.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Biópsia , Fibrose , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Índice de Gravidade de Doença , Brancos
5.
J Gastroenterol Hepatol ; 38(10): 1832-1839, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37596843

RESUMO

BACKGROUND AND AIMS: Both fibrosis status and body weight are important for assessing prognosis in nonalcoholic fatty liver disease (NAFLD). The aim of this study was to identify population clusters for specific clinical outcomes based on fibrosis-4 (FIB-4) index and body mass index (BMI) using an unsupervised machine learning method. METHODS: We conducted a multicenter study of 1335 biopsy-proven NAFLD patients from Japan. Using the Gaussian mixture model to divide the cohort into clusters based on FIB-4 index and BMI, we investigated prognosis for these clusters. RESULTS: The cohort consisted of 223 cases (16.0%) with advanced fibrosis (F3-4) as assessed from liver biopsy. Median values of BMI and FIB-4 index were 27.3 kg/m2 and 1.67. The patients were divided into four clusters by Bayesian information criterion, and all-cause mortality was highest in cluster d, followed by cluster b (P = 0.001). Regarding the characteristics of each cluster, clusters d and b presented a high FIB-4 index (median 5.23 and 2.23), cluster a presented the lowest FIB-4 index (median 0.78), and cluster c was associated with moderate FIB-4 level (median 1.30) and highest BMI (median 34.3 kg/m2 ). Clusters a and c had lower mortality rates than clusters b and d. However, all-cause of death in clusters a and c was unrelated to liver disease. CONCLUSIONS: Our clustering approach found that the FIB-4 index is an important predictor of mortality in NAFLD patients regardless of BMI. Additionally, non-liver-related diseases were identified as the causes of death in NAFLD patients with low FIB-4 index.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Teorema de Bayes , Aprendizado de Máquina não Supervisionado , Prognóstico , Fenótipo , Fibrose , Cirrose Hepática/etiologia , Cirrose Hepática/complicações , Biópsia , Índice de Gravidade de Doença , Fígado/patologia
6.
Plant J ; 106(6): 1523-1540, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33768644

RESUMO

Temperature passively affects biological processes involved in plant growth. Therefore, it is challenging to study the dedicated temperature signalling pathways that orchestrate thermomorphogenesis, a suite of elongation growth-based adaptations that enhance leaf-cooling capacity. We screened a chemical library for compounds that restored hypocotyl elongation in the pif4-2-deficient mutant background at warm temperature conditions in Arabidopsis thaliana to identify modulators of thermomorphogenesis. The small aromatic compound 'Heatin', containing 1-iminomethyl-2-naphthol as a pharmacophore, was selected as an enhancer of elongation growth. We show that ARABIDOPSIS ALDEHYDE OXIDASES redundantly contribute to Heatin-mediated hypocotyl elongation. Following a chemical proteomics approach, the members of the NITRILASE1-subfamily of auxin biosynthesis enzymes were identified among the molecular targets of Heatin. Our data reveal that nitrilases are involved in promotion of hypocotyl elongation in response to high temperature and Heatin-mediated hypocotyl elongation requires the NITRILASE1-subfamily members, NIT1 and NIT2. Heatin inhibits NIT1-subfamily enzymatic activity in vitro and the application of Heatin accordingly results in the accumulation of NIT1-subfamily substrate indole-3-acetonitrile in vivo. However, levels of the NIT1-subfamily product, bioactive auxin (indole-3-acetic acid), were also significantly increased. It is likely that the stimulation of hypocotyl elongation by Heatin might be independent of its observed interaction with NITRILASE1-subfamily members. However, nitrilases may contribute to the Heatin response by stimulating indole-3-acetic acid biosynthesis in an indirect way. Heatin and its functional analogues present novel chemical entities for studying auxin biology.


Assuntos
Aminoidrolases/metabolismo , Arabidopsis/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hipocótilo/efeitos dos fármacos , Aldeído Oxidase/genética , Aldeído Oxidase/metabolismo , Aminoidrolases/genética , Apomorfina/análogos & derivados , Apomorfina/farmacologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Herbicidas/farmacologia , Hipocótilo/crescimento & desenvolvimento , Ácidos Indolacéticos , Estrutura Molecular , Picloram/farmacologia , Relação Estrutura-Atividade , Transcriptoma/efeitos dos fármacos
7.
J Hepatol ; 77(6): 1573-1585, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36063968

RESUMO

BACKGROUND & AIMS: Non-invasive tests (NITs) for clinically significant portal hypertension (CSPH; hepatic venous pressure gradient [HVPG] ≥10 mmHg) have predominantly been studied in patients with active HCV infection. Investigations after HCV cure are limited and have yielded conflicting results. We conducted a pooled analysis to determine the diagnostic/prognostic utility of liver stiffness measurement (LSM)/platelet count (PLT) in this setting. METHODS: A total of 418 patients with pre-treatment HVPG ≥6 mmHg who achieved sustained virological response (SVR) and underwent post-treatment HVPG measurement were assessed, of whom 324 (HVPG/NIT-cohort) also had paired data on pre-/post-treatment LSM/PLT. The derived LSM/PLT criteria were then validated against the direct endpoint decompensation in 755 patients with compensated advanced chronic liver disease (cACLD) with SVR (cACLD-validation-cohort). RESULTS: HVPG/NIT-cohort: Among patients with cACLD, the pre-/post-treatment prevalence of CSPH was 80%/54%. The correlation between LSM/HVPG increased from pre- to post-treatment (r = 0.45 vs. 0.60), while that of PLT/HVPG remained unchanged. For given LSM/PLT values, HVPG tended to be lower post- vs. pre-treatment, indicating the need for dedicated algorithms. Combining post-treatment LSM/PLT yielded a high diagnostic accuracy for post-treatment CSPH in cACLD (AUC 0.884; 95% CI 0.843-0.926). Post-treatment LSM <12 kPa & PLT >150 G/L excluded CSPH (sensitivity: 99.2%), while LSM ≥25 kPa was highly specific for CSPH (93.6%). cACLD-validation-cohort: the 3-year decompensation risk was 0% in the 42.5% of patients who met the LSM <12 kPa & PLT >150 G/L criteria. In patients with post-treatment LSM ≥25 kPa (prevalence: 16.8%), the 3-year decompensation risk was 9.6%, while it was 1.3% in those meeting none of the above criteria (prevalence: 40.7%). CONCLUSIONS: NITs can estimate the probability of CSPH after HCV cure and predict clinical outcomes. Patients with cACLD but LSM <12 kPa & PLT>150 G/L may be discharged from portal hypertension surveillance if no co-factors are present, while patients with LSM ≥25 kPa require surveillance/treatment. LAY SUMMARY: Measurement of liver stiffness by a specific ultrasound device and platelet count (a simple blood test) are broadly used for the non-invasive diagnosis of increased blood pressure in the veins leading to the liver, which drives the development of complications in patients with advanced liver disease. The results of our pooled analysis refute previous concerns that these tests are less accurate after the cure of hepatitis C virus (HCV) infection. We have developed diagnostic criteria that facilitate personalized management after HCV cure and allow for a de-escalation of care in a high proportion of patients, thereby decreasing disease burden.


Assuntos
Hepatite C , Hipertensão Portal , Humanos , Hepacivirus , Hipertensão Portal/diagnóstico , Hipertensão Portal/etiologia , Pressão na Veia Porta , Resposta Viral Sustentada
8.
Biochem Biophys Res Commun ; 631: 64-71, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36174297

RESUMO

The human parasitic head and body lice lay their eggs on either hair or clothing. Attachments of the eggs are possible because the female lice secret a glue substance from the accessory gland along with the egg, which hardens into a nit sheath that secures and protects the egg (The "nit" commonly refers to either the louse egg with an embryo or the empty hatched egg). Proteins called the louse nit sheath protein (LNSP) are suggested to be the major proteins of the nit sheath, but transcriptome profiling of the accessory glands indicated other proteins such as Agp9 and Agp22 are also expressed in the glands. In this study, human body louse LNSP1 (partial), Agp9, and Agp22 are recombinantly produced using the E. coli expression system, and the biophysical properties characterized. Circular dichroism analysis indicated that the secondary structure elements of LNSP1 N-terminal and middle-domains, Agp9, and Agp22 are prominently random coiled with up to 10-30% anti-parallel ß-sheet element present. Size-exclusion chromatography profiles of LNSP1 proteins further suggested that the ß-sheets made of the smaller N-terminal domain stacks onto the ß-sheets of the larger middle-domain.


Assuntos
Infestações por Piolhos , Pediculus , Animais , Escherichia coli/genética , Feminino , Cabelo , Humanos , Infestações por Piolhos/parasitologia , Pediculus/química
9.
Molecules ; 27(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36144700

RESUMO

In the present study, metallophthalocyanines were modified with NIT nitroxide radicals through chemical bonds to prepare a series of metallophthalocyanines-NIT catalysts (MPcTcCl8-NIT, M=Mn2+, Fe2+, Co2+, Ni2+, Cu2+ and Zn2+) applied for oxidative desulfurization of thiophene (T) in model fuel. The MPcTcCl8-NIT catalysts were characterized by FTIR, UV-Vis, ESR, and XPS spectra. The oxidative desulfurization activity of MPcTcCl8-NIT catalysts was studied in a biomimetic catalytic system using molecular O2 as the oxidant. The MPcTcCl8-NIT catalysts exhibited high catalytic activities for the oxidation of thiophene in model fuel. The desulfurization rate of ZnPcTcCl8-NIT for thiophene reached to 99.61%, which was 20.53% higher than that of pure ZnPcTcCl8 (79.08%) under room temperature and natural light. The results demonstrated that MPcTcCl8-NIT catalysts could achieve more effective desulfurization rate under milder conditions than that of the metallophthalocyanines. The NIT nitroxide radicals also could improve the catalytic activity of metallophthalocyanine based on the synergistic oxidation effect. The stability experiments for ZnPcTcCl8-NIT showed that the catalyst still had a high desulfurization rate of 92.37% after five times recycling. All these findings indicate that the application of MPcTcCl8-NIT catalysts provides a potential new way for the desulfurization performance of thiophene in fuel.


Assuntos
Óxidos de Nitrogênio , Oxidantes , Estresse Oxidativo , Tiofenos/química
10.
Anal Biochem ; 632: 114332, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34391728

RESUMO

Nit2/ω-amidase catalyzes the hydrolysis of α-ketoglutaramate (KGM, the α-keto acid analogue of glutamine) to α-ketoglutarate and ammonia. The enzyme also catalyzes the amide hydrolysis of monoamides of 4- and 5-C-dicarboxylates, including α-ketosuccinamate (KSM, the α-keto acid analogue of asparagine) and succinamate (SM). Here we describe an inexpensive procedure for high-yield expression of human Nit2 (hNit2) in Escherichia coli and purification of the expressed protein. This work includes: 1) the design of a genetic construct (pQE-Nit22) obtained from the previously described construct (pQE-Nit2) by replacing rare codons within an 81 bp-long DNA fragment "preferred" by E. coli near the translation initiation site; 2) methods for producing and maintaining the pQE-Nit22 construct; 3) purification of recombinant hNit2; and 4) activity measurements of the purified enzyme with KGM and SM. Important features of the hNit2 gene within the pQE-Nit22 construct are: 1) optimized codon composition, 2) the presence of an N-terminus His6 tag immediately after the initiating codon ATG (Met) that permits efficient purification of the end-product on a Ni-NTA-agarose column. We anticipate that the availability of high yield hNit2/ω-amidase will be helpful in elucidating the normal and pathological roles of this enzyme and in the design of specific inhibitors.


Assuntos
Aminoidrolases/biossíntese , Escherichia coli/metabolismo , Aminoidrolases/química , Aminoidrolases/genética , Humanos
11.
Biochem J ; 476(4): 683-697, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30692244

RESUMO

The tripeptide glutathione (GSH) is implicated in various crucial physiological processes including redox buffering and protection against heavy metal toxicity. GSH is abundant in plants, with reported intracellular concentrations typically in the 1-10 mM range. Various aminotransferases can inadvertently transaminate the amino group of the γ-glutamyl moiety of GSH to produce deaminated glutathione (dGSH), a metabolite damage product. It was recently reported that an amidase known as Nit1 participates in dGSH breakdown in mammals and yeast. Plants have a hitherto uncharacterized homolog of the Nit1 amidase. We show that recombinant Arabidopsis Nit1 (At4g08790) has high and specific amidase activity towards dGSH. Ablating the Arabidopsis Nit1 gene causes a massive accumulation of dGSH and other marked changes to the metabolome. All plant Nit1 sequences examined had predicted plastidial targeting peptides with a potential second start codon whose use would eliminate the targeting peptide. In vitro transcription/translation assays show that both potential translation start codons in Arabidopsis Nit1 were used and confocal microscopy of Nit1-GFP fusions in plant cells confirmed both cytoplasmic and plastidial localization. Furthermore, we show that Arabidopsis enzymes present in leaf extracts convert GSH to dGSH at a rate of 2.8 pmol min-1 mg-1 in the presence of glyoxalate as an amino acceptor. Our data demonstrate that plants have a dGSH repair system that is directed to at least two cellular compartments via the use of alternative translation start sites.


Assuntos
Amidoidrolases , Aminoidrolases , Proteínas de Arabidopsis , Arabidopsis , Glutationa/metabolismo , Amidoidrolases/genética , Amidoidrolases/metabolismo , Aminoidrolases/genética , Aminoidrolases/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Citoplasma/enzimologia , Citoplasma/genética , Plastídeos/enzimologia , Plastídeos/genética
12.
Parasitology ; 146(5): 678-684, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30526723

RESUMO

Despite the common association of human lice with abandoned or neglected people, no procedure to assess pediculosis, aimed to detect signs of neglect, exists. Investigating the two most common forms of head louse infestation, regular and severe, we define lice-markers of neglect and develop a protocol and survey form to record and assess pediculosis. The study of head lice from a deceased victim of neglect helped unravel time-length since death, frequency of exposure to neglect and the cause and circumstances related to the death. Nit-clusters are markers of neglect, indicating length and frequency of neglect episodes. In the case study used here that culminated in the death of the victim, sustained abandonment started circa 2 years before discovery. The lice suggested that death was caused by overconsumption of a powerful calcium channel blocker, an antihypertensive, an excess of which in lice food supply (blood) stops oogenesis. Despite hosting thousands of adult females on the hair, lice reproduction stopped and nits were no longer developed or deposited on the hairs at the root end. This short distance of the shaft with no nits provided a time estimation of overdosing of almost 2 months before death.

13.
Microbiology (Reading) ; 164(7): 956-968, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781800

RESUMO

A genetic linkage between a conserved gene cluster (Nit1C) and the ability of bacteria to utilize cyanide as the sole nitrogen source was demonstrated for nine different bacterial species. These included three strains whose cyanide nutritional ability has formerly been documented (Pseudomonas fluorescens Pf11764, Pseudomonas putida BCN3 and Klebsiella pneumoniae BCN33), and six not previously known to have this ability [Burkholderia (Paraburkholderia) xenovorans LB400, Paraburkholderia phymatum STM815, Paraburkholderia phytofirmans PsJN, Cupriavidus (Ralstonia) eutropha H16, Gluconoacetobacter diazotrophicus PA1 5 and Methylobacterium extorquens AM1]. For all bacteria, growth on or exposure to cyanide led to the induction of the canonical nitrilase (NitC) linked to the gene cluster, and in the case of Pf11764 in particular, transcript levels of cluster genes (nitBCDEFGH) were raised, and a nitC knock-out mutant failed to grow. Further studies demonstrated that the highly conserved nitB gene product was also significantly elevated. Collectively, these findings provide strong evidence for a genetic linkage between Nit1C and bacterial growth on cyanide, supporting use of the term cyanotrophy in describing what may represent a new nutritional paradigm in microbiology. A broader search of Nit1C genes in presently available genomes revealed its presence in 270 different bacteria, all contained within the domain Bacteria, including Gram-positive Firmicutes and Actinobacteria, and Gram-negative Proteobacteria and Cyanobacteria. Absence of the cluster in the Archaea is congruent with events that may have led to the inception of Nit1C occurring coincidentally with the first appearance of cyanogenic species on Earth, dating back 400-500 million years.


Assuntos
Aminoidrolases/genética , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Cianetos/metabolismo , Família Multigênica/genética , Aminoidrolases/metabolismo , Bactérias/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Sequência Conservada , Evolução Molecular , Deleção de Genes , Ligação Genética , Transcrição Gênica
14.
BMC Plant Biol ; 18(1): 251, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30348089

RESUMO

BACKGROUND: Nitrilases are nitrile-converting enzymes commonly found within the plant kingdom that play diverse roles in nitrile detoxification, nitrogen recycling, and phytohormone biosynthesis. Although nitrilases are present in all higher plants, little is known about their function in trees. Upon herbivory, poplars produce considerable amounts of toxic nitriles such as benzyl cyanide, 2-methylbutyronitrile, and 3-methylbutyronitrile. In addition, as byproduct of the ethylene biosynthetic pathway upregulated in many plant species after herbivory, toxic ß-cyanoalanine may accumulate in damaged poplar leaves. In this work, we studied the nitrilase gene family in Populus trichocarpa and investigated the potential role of the nitrilase PtNIT1 in the catabolism of herbivore-induced nitriles. RESULTS: A BLAST analysis revealed three putative nitrilase genes (PtNIT1, PtNIT2, PtNIT3) in the genome of P. trichocarpa. While PtNIT1 was expressed in poplar leaves and showed increased transcript accumulation after leaf herbivory, PtNIT2 and PtNIT3 appeared not to be expressed in undamaged or herbivore-damaged leaves. Recombinant PtNIT1 produced in Escherichia coli accepted biogenic nitriles such as ß-cyanoalanine, benzyl cyanide, and indole-3-acetonitrile as substrates in vitro and converted them into the corresponding acids. In addition to this nitrilase activity, PtNIT1 showed nitrile hydratase activity towards ß-cyanoalanine, resulting in the formation of the amino acid asparagine. The kinetic parameters of PtNIT1 suggest that the enzyme utilizes ß-cyanoalanine and benzyl cyanide as substrates in vivo. Indeed, ß-cyanoalanine and benzyl cyanide were found to accumulate in herbivore-damaged poplar leaves. The upregulation of ethylene biosynthesis genes after leaf herbivory indicates that herbivore-induced ß-cyanoalanine accumulation is likely caused by ethylene formation. CONCLUSIONS: Our data suggest a role for PtNIT1 in the catabolism of herbivore-induced ß-cyanoalanine and benzyl cyanide in poplar leaves.


Assuntos
Aminoidrolases/metabolismo , Nitrilas/metabolismo , Populus/enzimologia , Alanina/análogos & derivados , Alanina/metabolismo , Aminoidrolases/genética , Herbivoria , Folhas de Planta/enzimologia , Folhas de Planta/genética , Populus/genética
15.
Catheter Cardiovasc Interv ; 91(3): 478-484, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29399946

RESUMO

BACKGROUND: Nit-Occlud® (atrial septal defect) ASD-R and (patent ductus arteriosus) PDA-R devices are used outside the United States for percutaneous closure of the patent ductus arteriosus and atrial septal defects. When embolization occurs, these devices have been difficult to retrieve. METHODS: Bench simulations of retrieval of PDA-R and ASD-R devices were performed in a vascular model. Retrieval of each device was attempted using snare techniques or with bioptome forceps with a range of devices. The same devices were then intentionally embolized in an animal model. Retrieval methods were systematically tested in a range of sheath sizes, and graded in terms of difficulty and retrieval time. RESULTS: Devices that were grasped by the bioptome in the center of the proximal part of the devices were easily retrieved in both models. Bench studies determined the minimum sheath sizes needed for retrieval of each device with this method. In general sheathes two french sizes greater than the delivery sheath were successful with this technique. Three out of the four PDA-R devices were successfully retrieved in vivo. Two were retrieved by grasping the middle of the PA end of the PDA-R device with a Maslanka bioptome and one small PDA-R device was retrieved using a 10 mm Snare. Four of the five ASD-R devices were retrieved successfully grasping the right atrial ASD-R disc or by passing a wire through the device and snaring this loop. For ASD-R 28 and 30 mm devices, a double bioptome technique was needed to retrieve the device. CONCLUSION: ASD-R and PDA-R devices can be successfully retrieved in the catheterization lab. It is critical to grab the center portion of the right atrial disc of the ASD-R device or pulmonary portion of the PDA-R device and to use adequately sized sheathes.


Assuntos
Cateterismo Cardíaco/métodos , Cateterismo Periférico/métodos , Remoção de Dispositivo/métodos , Migração de Corpo Estranho/terapia , Dispositivo para Oclusão Septal/efeitos adversos , Animais , Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Cateterismo Periférico/instrumentação , Remoção de Dispositivo/instrumentação , Modelos Animais de Doenças , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia , Humanos , Modelos Anatômicos , Modelos Cardiovasculares , Desenho de Prótese , Radiografia Intervencionista , Instrumentos Cirúrgicos , Sus scrofa , Dispositivos de Acesso Vascular
16.
J Environ Manage ; 218: 234-244, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29680755

RESUMO

A cyanobacterial strain, Synechococcus sp. NIT18, has been applied to sequester CO2 using sodium carbonate as inorganic carbon source due to its efficiency of CO2 bioconversion and high biomass production. The biomass obtained is used for the extraction of biomolecules - protein, carbohydrate and lipid. The main objective of the study is to maximize the biomass and biomolecules production with CO2 sequestration using cyanobacterial strain cultivated under different concentrations of CO2 (5-20%), pH (7-11) and inoculum size (5-12.5%) within a statistical framework. Maximum sequestration of CO2 and maximum productivities of protein, carbohydrate and lipid are 71.02%, 4.9 mg/L/day, 6.7 mg/L/day and 1.6 mg/L/day respectively, at initial CO2 concentration: 10%, pH: 9 and inoculum size: 12.5%. Since flue gas contains 10-15% CO2 and the present strain is able to sequester CO2 in this range, the strain could be considered as a useful tool for CO2 mitigation for greener world.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Biomassa , Carbono , Cianobactérias , Lipídeos
17.
J Cell Biochem ; 118(12): 4349-4357, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28436095

RESUMO

Mounting studies have indicated the role of berberine, SIRT1, and oxidative stress in diabetes, respectively. However, few studies have demonstrated their correlation and regulation function in diabetes. Therefore, the protective effect of berberine in diabetic and the underlying core mechanism were investigated in the current study. Diabetic mice model in vivo were established. Mouse pancreatic beta-cell line NIT-1 cells were treated with 30 mM high glucose to induce diabetic condition in vitro. Serum biochemical parameters (glucose, total cholesterol, and triglycerides) were detected. Oxidative stress indicators (MDA, SOD1), along with miR-106b and SIRT1 expression in islets and cells were also assessed. Direct targeting relationship between miR-106b and SIRT1 was discussed by dual luciferase reporter gene assay. Diabetic model in vivo and in vitro were both established successfully. The expression of serum biochemical parameters was increased, and oxidative stress parameters, and miR-106b, SIRT1 were abnormally expressed in diabetic mice and NIT-1 cells. Meanwhile, berberine could alleviate oxidative stress injury in diabetic progression. Through dual luciferase reporter gene assay, we found that SIRT1 was a target gene of miR-106b. In addition, miR-106b over-expression could reverse the protection of berberine in NIT-1 cells against from oxidative stress induced by high glucose. Berberine could attenuate oxidative stress of diabetic mice at least partly through miR-106b/SIRT1 pathway and affecting the function of islets, which might be beneficial in reducing the cardiovascular risk factors in diabetes. J. Cell. Biochem. 118: 4349-4357, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Berberina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Ilhotas Pancreáticas/metabolismo , MicroRNAs/biossíntese , Estresse Oxidativo , Sirtuína 1/biossíntese , Regulação para Cima/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/patologia , Ilhotas Pancreáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR
19.
Ecotoxicology ; 26(7): 956-965, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28623432

RESUMO

Involvement of genes (CYS-A1, CYS-C1 and NIT4) encoded with cysteine synthase, ß-cyanoalanine synthase, nitrilase and cyanide metabolisms are evident in Arabidopsis. In the present study, identifications of CYS-A1, CYS-C1 and NIT4, predictions of conserved motifs, and constructions of phylogenetic relationships, based on their amino acid sequences in rice, were conducted. In order to elucidate the transcriptional responses of these cyanide-degrading genes, two candidate homologues were selected for each gene to test their expression changes upon exposure to exogenous KCN in rice seedlings using RT-PCR. Results showed that all selected candidate homologous genes were differentially expressed at different exposure points in roots and shoots of rice seedlings, suggesting their distinct roles during cyanide assimilation. Both candidate homologues for CYS-A1 constantly exhibited more abundant transcripts in comparison to control. However, only one candidate homologue for CYS-C1 and NIT4 showed a remarkable up-regulation during KCN exposure. Analysis of both tissue and solution cyanide indicated that rice seedlings were quickly able to metabolize exogenous KCN with minor accumulation in plant tissues. In conclusion, significant up-regulation of CYS-A1 suggested that the endogenous pool of cysteine catalyzed by cysteine synthase does not restrict the conversion of exogenous KCN into cyanoalanine through the ß-cyanoalanine pathway. However, insufficient responses of the transcription level of NIT4 suggested that NIT enzyme may be a limiting factor for cyanoalanine assimilation by rice seedlings.


Assuntos
Cianetos/toxicidade , Genes de Plantas , Oryza/fisiologia , Proteínas de Plantas/genética , Poluentes do Solo/toxicidade , Aminoidrolases/genética , Cisteína Sintase/genética , Expressão Gênica , Liases/genética , Oryza/genética
20.
Pediatr Cardiol ; 38(4): 828-832, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28224170

RESUMO

We studied the safety and efficacy of closing patent ductus arteriosus by Nit-Occlud coils via retrograde approach. This is a retrospective study of 46 attempts to close ducts by this method in two hospitals in Egypt and Iran. Ductus arteriosus was crossed by left or right Judkins or endhole catheters. The coil was delivered via the same catheter or the provided endhole catheter after exchange. The procedure was successful in 42 out of 46 attempts. Fluoroscopy and procedural times were significantly shorter when the catheter was not exchanged. This method is effective and safe for the closure of small ducts. Crossing the duct and delivering the coil by a left Judkins catheter is the easiest and fastest way to perform this method.


Assuntos
Permeabilidade do Canal Arterial/cirurgia , Embolização Terapêutica/instrumentação , Adolescente , Cateterismo Cardíaco , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Uso Off-Label , Estudos Retrospectivos
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