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1.
Mar Environ Res ; 193: 106293, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103302

RESUMO

Here we provide evidence, along an 8-year period time-series based on multifaceted data from a Mediterranean marine protected area (MPA), whether protection can tackle invasive and range expanding herbivore fishes, and their effects on the algal resource availability, taking into account the population trends of predatory fishes, fisheries catches of herbivore fishes and sea surface temperature (SST) through time. Our findings pointed out that an ineffective in restoring top-down control process MPA may facilitate, rather than alleviate, the sudden and enduring population burst of invasive and range-expanding herbivorous fishes at tipping points of abrupt change. This subsequently results in the deterioration of rocky reef habitats and the depletion of algal resources, with the tipping points of abrupt change for algal and herbivore fish species not overlapping chronologically. As sea temperature increases, ineffective or recently established MPAs may inadvertently facilitate the proliferation of invasive and range-expanding species, posing a significant challenge to management effectiveness and conservation objectives.


Assuntos
Ecossistema , Herbivoria , Animais , Peixes , Pesqueiros , Temperatura , Conservação dos Recursos Naturais
2.
Zootaxa ; 4668(4): zootaxa.4668.4.11, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31716614

RESUMO

The fire coral Millepora platyphylla Hemprich Ehrenberg, 1834 (Cnidaria, Hydrozoa) has a widespread Indo-Pacific distribution observed from the surface to 40 m (Razak Hoeksema 2003). However, its extirpation from the East Pacific (Gulf of Chiriqui, Panama) was documented after the 1982-1983 bleaching event (Glynn Weerdt 1991). Here, we report the discovery of 5 colonies of M. platyphylla from the eastern Pacific, specifically at Clipperton Atoll, during the TARA Pacific expedition (www.taraexpeditions.org).


Assuntos
Antozoários , Cnidários , Hidrozoários , Animais , Expedições , Panamá
3.
Mar Pollut Bull ; 131(Pt A): 552-564, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29886982

RESUMO

Blooms of Ostreopsis cf. ovata, causing health incidence and mass human intoxications in the Mediterranean, gained special attention over the past decades. To study the potential effects of temperature and nutrient enrichment on this benthic dinoflagellate and other associated microalgae in situ, a multifactorial experiment was set up along a temperature gradient of a heat pump system in Monaco. Microalgae were quantified in experimental units, in the natural biofilm and in the water column. No significant interaction was observed between temperature and nutrients. A species- and bloom phase-dependent effect of the increased temperature was recorded, while the nutrient enrichment had a significant effect only at the end of the experiment (when cell abundances were low). Temperature effects were also visible in the biofilm and the surrounding water. The observed assemblages were mainly driven by changes in abundances of Ostreopsis cf. ovata and Actinocyclus sp., affected in different ways.


Assuntos
Diatomáceas/fisiologia , Dinoflagellida/fisiologia , Proliferação Nociva de Algas , Microalgas/fisiologia , Aquecimento Global , Nitrogênio/análise , Fósforo/análise , Estresse Fisiológico , Temperatura
5.
J Inherit Metab Dis ; 32(1): 10-21, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18937047

RESUMO

The biochemical properties of mutant phenylalanine hydroxylase (PAH) enzymes and clinical characteristics of hyperphenylalaninaemic patients who bear these mutant enzymes were investigated. Biochemical characterization of mutant PAH enzymes p.D143G, p.R155H, p.L348V, p.R408W and p.P416Q included determination of specific activity, substrate activation, V(max), K(m) for (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)), K (d) for BH(4), and protein stabilization by BH(4). Clinical data from 22 patients either homozygous, functionally hemizygous, or compound heterozygous for the mutant enzymes of interest were correlated with biochemical parameters of the mutant enzymes. The p.L348V and p.P416Q enzymes retain significant catalytic activity yet were observed in classic and moderate PKU patients. Biochemical studies demonstrated that BH(4) rectified the stability defects in p.L348V and p.P416Q; additionally, patients with these variants responded to BH(4) therapy. The p.R155H mutant displayed low PAH activity and decreased apparent affinity for L-Phe yet was observed in mild hyperphenylalaninaemia. The p.R155H mutant does not display kinetic instability, as it is stabilized by BH(4) similarly to wild-type PAH; thus the residual activity is available under physiological conditions. The p.R408W enzyme is dysfunctional in nearly all biochemical parameters, as evidenced by disease severity in homozygous and hemizygous patients. Biochemical assessment of mutant PAH proteins, especially parameters involving interaction with BH(4) that impact protein folding, appear useful in clinical correlation. As additional patients and mutant proteins are assessed, the utility of this approach will become apparent.


Assuntos
Fenilalanina Hidroxilase/genética , Fenilalanina Hidroxilase/metabolismo , Fenilcetonúrias/genética , Adulto , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Dicroísmo Circular , Escherichia coli/enzimologia , Escherichia coli/genética , Fluorescência , Humanos , Recém-Nascido , Cinética , Mutagênese Sítio-Dirigida , Proteínas Mutantes/análise , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto/fisiologia , Organismos Geneticamente Modificados , Fenilalanina Hidroxilase/análise , Fenilalanina Hidroxilase/química , Fenilcetonúrias/enzimologia , Fenilcetonúrias/metabolismo , Fenilcetonúrias/patologia , Ligação Proteica/genética , Dobramento de Proteína , Estabilidade Proteica , Adulto Jovem
7.
Surg Endosc ; 20(8): 1208-13, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16865623

RESUMO

BACKGROUND: Laparoscopic splenectomy (LS) offers better short-term results than open surgery for the treatment of immune thrombocytopenic purpura (ITP), but long-term follow-up is required to ensure its efficacy. The remission rate after splenectomy ranges from 49 to 86% and the factors that predict a successful response to surgical management have not been clearly defined. The goal of this study was to determine the preoperative factors that predict a successful outcome following LS. METHODS: From February 1993 to December 2003, LS was consecutively performed in a series of 119 nonselected patients diagnosed with ITP (34 men and 85 women; mean age, 41 years), and clinical results were prospectively recorded. Postoperative follow-up was based on clinical records, follow-up data provided by the referring hematologist, and a phone interview with the patient and/or relative. Univariate and multivariate analyses were performed for clinical preoperative variables to identify predictive factors of success following LS. RESULTS: Over a mean period of 33 months, 103 patients (84%) were available for follow-up with a remission rate of 89% (92 patients, 77 with complete remission with platelet count > 150,000). Eleven patients did not respond to surgery (platelet count < 50,000). Mortality during follow-up was 2.5% (two cases not related to hematological pathology and one case without response to splenectomy). Preoperative clinical variables evaluated to identify predictive factors of response to surgery were sex, age, treatment (corticoids alone or associated with Ig or chemotherapy), other immune pathology, duration of disease, and preoperative platelet count. In a subgroup of 52 patients, we also evaluated the type of autoantibodies and corticoid doses required to maintain a platelet count > 50,000. Multivariate analysis showed that none of the variables evaluated could be considered as predictive factors of response to LS due to the high standard error. CONCLUSION: Long-term clinical results show that LS is a safe and effective therapy for ITP. However, a higher number of nonresponders is needed to determine which variables predict response to LS for ITP.


Assuntos
Doenças do Sistema Imunitário/cirurgia , Laparoscopia , Púrpura Trombocitopênica/cirurgia , Esplenectomia , Adolescente , Adulto , Idoso , Feminino , Humanos , Doenças do Sistema Imunitário/sangue , Doenças do Sistema Imunitário/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Contagem de Plaquetas , Prognóstico , Estudos Prospectivos , Púrpura Trombocitopênica/sangue , Púrpura Trombocitopênica/mortalidade , Indução de Remissão , Resultado do Tratamento
8.
Surg Endosc ; 18(8): 1283-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15457387

RESUMO

BACKGROUND: Laparoscopic splenectomy (LS) has been demonstrated as an effective and safe treatment for hematological disorders requiring spleen removal, especially in cases of normal-sized spleens. However, although results are promising, long-term outcome data are lacking. We reviewed our clinical experience with LS in a series of 255 cases, with particular attention to the long-term outcome related to the disease process requiring LS. METHODS: From February 1993 to October 2003, LS was attempted in 255 patients (100 males and 155 females with a mean age of 45 +/- 19 years) and clinical information was recorded in a prospective database. Indications for splenectomy included idiopathic thrombocytopenic purpura (ITP) (n = 115), HIV-ITP (n = 9), Evans syndrome (n = 6), autoimmune hemolytic anemia (AIHA) (n = 13), hereditary spherocytosis (HS) (n = 19), hematologic malignancy (n = 66), thrombotic thrombocytopenic purpura (n = 1), and others (n = 26). Long-term postoperative follow-up evaluation was obtained through clinical notes, follow-up visits by the referring hematologist, and by phone interviews both with patients and with the referring hematologist. RESULTS: A total of 186 patients (73%) were available for a mean follow-up of 35 months (range, 1-104). Of the ITP patients, 87 (76%) were followed up, with a remission rate of 89% (complete remission in 75%). A similar remission rate was observed in ITP-HIV; in patients available for follow-up (78%), complete remission was achieved in 83%. In Evans, complete remission was achieved in all patients available for follow-up (67%). Clinical response for hemolytic disease ranged between 70% for AIHA and 100% for HS. In the malignant group, the late mortality rate was 22%. The mortality rate in the miscellaneous group was 5%. No cases of splenectomy-related sepsis occurred during follow-up. CONCLUSIONS: LS offers advantages for all types of splenic diseases requiring surgery. It provides not only good clinical short-term outcome but also satisfactory long-term hematological results.


Assuntos
Doenças Hematológicas/cirurgia , Laparoscopia/métodos , Esplenectomia/métodos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Resultado do Tratamento
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