Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
BJOG ; 126(13): 1633-1640, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31483939

RESUMO

OBJECTIVE: To evaluate enzymatic total serum bile acid quantification as a monitoring strategy for women with intrahepatic cholestasis of pregnancy (ICP) treated with ursodeoxycholic acid (UDCA). DESIGN: Cohort. SETTING: One UK university hospital. POPULATION: 29 ICP cases treated with UDCA. METHODS: Serial samples were collected prospectively throughout gestation. Total serum bile acids were measured enzymatically and individual bile acids by high-performance liquid chromatography-tandem mass spectrometry. Data were log-transformed and analysed with random effects generalised least square regression. MAIN OUTCOME MEASURES: The relationship between enzymatic total bile acid measurements and individual bile acid concentrations after UDCA treatment. RESULTS: In untreated women, cholic acid was the principal bile acid (51%) and UDCA concentrations were <0.5%, whereas UDCA constituted 60% (IQR 43-69) of serum bile acids following treatment and cholic acid fell to <20%. Changes in the total bile acid measurement reflected similar alterations in the concentrations of the pathologically elevated bile acids, e.g. a two-fold increase in enzymatic total bile acids is accompanied by approximately a two-fold increase in cholic acid and chenodeoxycholic acid at most UDCA doses (P < 0.001). Most of the effects of UDCA on cholic acid occur in the first week of treatment (60% relative reduction, P = 0.025, 95% CI 0.2-0.9, from 10 micromol/l (4.7-17.6) to 3.5 micromol/l (1.4-7.5). CONCLUSION: Ursodeoxycholic acid becomes the main component of the bile acid measurement after treatment. Enzymatic total bile acid assays are good predictors of both cholic acid and chenodeoxycholic acid, the primary bile acids that are raised prior to treatment. TWEETABLE ABSTRACT: Ursodeoxycholic acid constitutes approximately 60% of the bile acid measurement and reduces pathological cholic acid in treated women.


Assuntos
Ácidos e Sais Biliares/sangue , Colagogos e Coleréticos/uso terapêutico , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/tratamento farmacológico , Complicações na Gravidez/sangue , Complicações na Gravidez/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Feminino , Humanos , Testes de Função Hepática , Gravidez , Estudos Prospectivos , Resultado do Tratamento
2.
J Appl Microbiol ; 124(2): 398-407, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29159916

RESUMO

AIMS: The aim of this study was to investigate the antimicrobial potential of proteins secreted by a new strain of Lactobacillus salivarius. METHODS AND RESULTS: The secretome of L. salivarius SGL 03 strain was analysed by gel-assisted fractionation and MS/MS to identify low-molecular-mass proteins. This strategy allowed us to identify 10 secreted proteins. Then, a combination of heterologous expression and agar well diffusion was used to characterize them as to their antimicrobial activity, mechanisms of action and stability. Our findings indicate that L27 and L30 proteins of the 50S ribosomal subunit have antimicrobial activity against Streptococcus pyogenes, Streptococcus uberis and Enterococcus faecium. In addition, both proteins are bactericidal against S. pyogenes and maintain their antimicrobial activity after different protease treatments, at acidic pH, after heat treatment, and if stored in a refrigerated ambient at least at 4°C. CONCLUSIONS: The overall results demonstrated that the L27 and L30 ribosomal proteins are of interest as new antimicrobial molecules to prevent the growth of S. pyogenes, S. uberis and E. faecium. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide the first insight into the extra-ribosomal activity of L27 and L30 secreted proteins of L. salivarius. This study demonstrated the capacity of L. salivarius SGL 03 to produce antimicrobial molecules and suggested this strain as a promising probiotic candidate.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Ligilactobacillus salivarius/metabolismo , Proteínas Ribossômicas/isolamento & purificação , Proteínas Ribossômicas/farmacologia , Antibacterianos/química , Enterococcus faecium/efeitos dos fármacos , Humanos , Ligilactobacillus salivarius/química , Ligilactobacillus salivarius/classificação , Proteínas Ribossômicas/química , Streptococcus/efeitos dos fármacos , Espectrometria de Massas em Tandem
3.
J Fish Biol ; 90(1): 129-146, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27730634

RESUMO

The head morphology and feeding habits of pairs of characin species (family Characidae) that coexist in four different coastal rainforest streams were analysed. Coexisting species differed in size, but were very similar in eco-morphological attributes. Gut analyses revealed differences in feeding preferences for each coexisting species, indicating resource partitioning. A pattern of organization in species pairs that was repeated in the four studied streams was noticed. The pattern consisted of one slightly larger species with a feeding preference for items of allochthonous origin and another smaller species with a preference for autochthonous items. The hypothesis that small morphological differences enable the current coexistence of those species pairs was proposed. Furthermore, the results show ecological equivalence among different species in the studied streams.


Assuntos
Characidae/anatomia & histologia , Characidae/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Animais , Tamanho Corporal , Preferências Alimentares , Rios
4.
J Econ Entomol ; 109(1): 222-31, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26511982

RESUMO

The pine weevils that occur in plantations of Pinus spp. in Andean Patagonia of Argentina belong to the species Pissodes castaneus (De Geer), a Eurasian endemic species, according to the identification based on molecular and morphological characters. Sequences of the mitochondrial Cytochrome oxidase subunit I and nuclear genes (28 S rDNA and ITS2) were obtained for individuals of 13 afforestations, covering the entire distribution area of the established populations in the Andean Patagonia of Argentina. Sequence comparison with representative species of the genus (European, North American, and Chinese species) shows that Patagonian specimens are conspecific to those of P. castaneus sequenced from Europe. Phylogenetic analyses indicate that all terminals from Patagonia form a monophyletic unit without evident subclades, eliminating the possibility of existence of more than one species of Pissodes Germar in this area, including cryptic ones. Moreover, the very low genetic divergence between the Patagonian populations suggests that it is plausible that P. castaneus was introduced into Patagonia from just one location. Mitochondrial DNA analysis shows that Patagonian terminals group together with a French haplotype and are clearly separated from other P. castaneus individuals represented in our sample, and reveal that established populations in Andean Patagonia originated via a limited introduction.


Assuntos
DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , RNA Ribossômico 28S/genética , Gorgulhos/fisiologia , Animais , Argentina , Núcleo Celular/genética , DNA Mitocondrial/genética , Espécies Introduzidas , Dados de Sequência Molecular , Filogenia , Filogeografia , Dinâmica Populacional , Alinhamento de Sequência , Análise de Sequência de DNA , Gorgulhos/genética
5.
Langenbecks Arch Surg ; 400(3): 319-24, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25749741

RESUMO

PURPOSE: Hypoparathyroidism is one of the most common and most feared complications of total thyroidectomy (TT). The aim of this study is to detect possible markers that may facilitate early tracing of hypocalcaemia-prone patients in order to reduce clinical cost by optimizing patient discharge and to avoid unnecessary treatment. METHODS: Over an 18-month period, 995 patients, 23 % male and 77 % female, aged 52.9 ± 13.4 years, underwent TT in ten Lombardy hospitals. The following parameters were analyzed: calcaemia before and 12-24 and 48 h after surgery, pre- and post-operative parathyroid hormone (PTH) at 24 h and pre-operative 25OH vitamin D. RESULTS: Mortality was nil and morbidity was 22.4 %. Mean 24-h calcaemia and PTH were 2.17 ± 0.15 mmol/l and 31.81 ± 20.35 pg/ml, respectively; mean 24-h PTH decay was 36.7 ± 34.12 %. Four hundred seventy-three (47.5 %) patients were hypocalcaemic at discharge; 142 of whom had transient hypoparathyroidism that became permanent in 27. Patients developing hypocalcaemia had significantly higher values of PTH and calcium decay. At multiple logistic regression, only 24-h calcium decay, PTH drop and the presence of symptoms and parathyroid auto-grafting were significantly related to hypoparathyroidism. The association of these factors had a 99.2 % negative predictive value (NPV) for the development of hypoparathyroidism. A 70 % PTH drop had a 93.75 NPV for transient hypoparathyroidism. A 12 % calcaemia decay had a 95.7 NPV for hypoparathyroidism. CONCLUSIONS: Hypocalcaemic asymptomatic patients with less than 70 % PTH and 12 % calcaemia decay may be safely discharged without treatment. Symptomatic patients and those with parathyroid grafting should receive calcium and vitamin D.


Assuntos
Hipocalcemia/etiologia , Hipoparatireoidismo/etiologia , Complicações Pós-Operatórias/etiologia , Tireoidectomia , Cálcio/uso terapêutico , Feminino , Humanos , Hipocalcemia/sangue , Hipocalcemia/tratamento farmacológico , Hipoparatireoidismo/sangue , Hipoparatireoidismo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Prospectivos , Fatores de Risco , Vitamina D/uso terapêutico
6.
J Synchrotron Radiat ; 21(Pt 3): 594-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24763650

RESUMO

The progress of tomographic coherent diffractive imaging with hard X-rays at the ID10 beamline of the European Synchrotron Radiation Facility is presented. The performance of the instrument is demonstrated by imaging a cluster of Fe2P magnetic nanorods at 59 nm 3D resolution by phasing a diffraction volume measured at 8 keV photon energy. The result obtained shows progress in three-dimensional imaging of non-crystalline samples in air with hard X-rays.

7.
Front Cardiovasc Med ; 11: 1232269, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322766

RESUMO

Background: Immune checkpoint blockade in monotherapy or combinatorial regimens with chemotherapy or radiotherapy have become an integral part of oncology in recent years. Monoclonal antibodies against CTLA-4 or PD-1 or PDL-1 are the most studied ICIs in randomized clinical trials, however, more recently, an anti-LAG3 (Lymphocyte activation gene-3) antibody, Relatlimab, has been approved by FDA in combination with Nivolumab for metastatic melanoma therapy. Moreover, Atezolizumab is actually under study in association with Ipilimumab for therapy of metastatic lung cancer. Myocarditis, vasculitis and endothelitis are rarely observed in these patients on monotherapy, however new combination therapies could expose patients to more adverse cardiovascular events. Methods: Human cardiomyocytes co-cultured with human peripheral blood lymphocytes (hPBMCs) were exposed to monotherapy and combinatorial ICIs (PD-L1 and CTLA-4 or PD-1 and LAG-3 blocking agents, at 100 nM) for 48 h. After treatments, cardiac cell lysis and secretion of biomarkers of cardiotoxicity (H-FABP, troponin-T, BNP, NT-Pro-BNP), NLRP3-inflammasome and Interleukin 1 and 6 were determined through colorimetric and enzymatic assays. Mitochondrial functions were studied in cardiomyocyte cell lysates through quantification of intracellular Ca++, ATP content and NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) levels. Histone deacetylases type 4 (HDAC-4) protein levels were also determined in cardiomyocyte cell lysates to study potential epigenetic changes induced by immunotherapy regimens. Results: Both combinations of immune checkpoint inhibitors exert more potent cardiotoxic side effects compared to monotherapies against human cardiac cells co-cultured with human lymphocytes. LDH release from cardiac cells was 43% higher in PD-L1/CTLA-4 blocking agents, and 35.7% higher in PD-1/LAG-3 blocking agents compared to monotherapies. HDAC4 and intracellular Ca++ levels were increased, instead ATP content and Ndufs1 were reduced in myocardial cell lysates (p < 0.001 vs. untreated cells). Troponin-T, BNP, NT-Pro-BNP and H-FABP, were also strongly increased in combination therapy compared to monotherapy regimen. NLRP3 expression, IL-6 and IL-1ß levels were also increased by PDL-1/CTLA-4 and PD-1/LAG-3 combined blocking agents compared to untreated cells and monotherapies. Conclusions: Data of the present study, although in vitro, indicate that combinatorial immune checkpoint blockade, induce a pro- inflammatory phenotype, thus indicating that these therapies should be closely monitored by the multidisciplinary team consisting of oncologists, cardiologists and immunologists.

8.
J Family Med Prim Care ; 12(3): 590-593, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37122663

RESUMO

In spite of advances in medical sciences, diagnosis of ectopic pregnancy eludes the clinician. In this case series, we describe three variants of life-threatening pregnancies. The successful management of these cases hinged on a strong index of suspicion and early detection. Heterotopic pregnancy is the occurrence of two pregnancies in different implantation sites at the same time, which is uncommon. Heterotopic pregnancy is uncommon in natural conception, despite its prevalence in assisted reproductive technologies. A strong index of suspicion and timely laparotomy was life-saving for the woman. Caesarean scar pregnancy is a form of ectopic pregnancy in which an aberrant pregnancy is implanted at the hysterotomy site of a prior caesarean procedure. Unexplained excessive bleeding at the time of medical termination of pregnancy prompted us to explore and make a timely diagnosis of caesarean scar pregnancy. Finally, tubal choriocarcinoma is a very aggressive, extremely rare trophoblastic tumour that can be either gestational or non-gestational. High serum beta HCG raised the suspicion and timely laparotomy confirmed the diagnosis. An alert clinician who takes timely decisions can avert life-threatening complications in these pregnancies.

9.
Nanotechnology ; 22(28): 285307, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21646692

RESUMO

Here we propose and experimentally demonstrate a hybrid photonic crystal (PC) slab consisting of air rods in a nanocomposite prepared by incorporating CdSe/CdS core/shell NRs (NR) in a polymer. Since the styrene methyl acrylate based polymer (ZEP) is transparent in the visible spectral range and is an electron-sensitive material, it was chosen as the embedding matrix for the NRs. Scanning electron microscopy and luminance measurements were used to characterize the experimental structure. The vertical extraction of the light, by the coupling of the modes guided by the PC slab to the free radiation via Bragg scattering, consists of a narrow orange emission band at 592 nm with a full width at half-maximum (FWHM) of 17 nm. The original characteristics of hybrid materials based on polymers and colloidal NRs, able to combine the unique optical properties of the inorganic moiety with the processability of the host matrix, are extremely appealing in view of their technological impact on the development of new high performing optical devices such as organic light-emitting diodes, ultra-low threshold lasers and non-linear devices.

10.
Nature ; 404(6773): 59-61, 2000 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-10716439

RESUMO

Nanometre-size inorganic dots, tubes and wires exhibit a wide range of electrical and optical properties that depend sensitively on both size and shape, and are of both fundamental and technological interest. In contrast to the syntheses of zero-dimensional systems, existing preparations of one-dimensional systems often yield networks of tubes or rods which are difficult to separate. And, in the case of optically active II-VI and III-V semiconductors, the resulting rod diameters are too large to exhibit quantum confinement effects. Thus, except for some metal nanocrystals, there are no methods of preparation that yield soluble and monodisperse particles that are quantum-confined in two of their dimensions. For semiconductors, a benchmark preparation is the growth of nearly spherical II-VI and III-V nanocrystals by injection of precursor molecules into a hot surfactant. Here we demonstrate that control of the growth kinetics of the II-VI semiconductor cadmium selenide can be used to vary the shapes of the resulting particles from a nearly spherical morphology to a rod-like one, with aspect ratios as large as ten to one. This method should be useful, not only for testing theories of quantum confinement, but also for obtaining particles with spectroscopic properties that could prove advantageous in biological labelling experiments and as chromophores in light-emitting diodes.

11.
Benef Microbes ; 11(6): 547-559, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33032472

RESUMO

Hyperoxaluria is a pathological condition which affects long-term health of kidneys. The present study evaluates the impact of the combination of Lactobacillus amylovorus SGL 14 and the plant extract Phyllantus niruri (namely Phyllantin 14™) on dietary hyperoxaluria. Safety and efficacy of Phyllantin 14 have been evaluated in vivo. Mice C57BL6 fed a high-oxalate diet were compared to mice fed the same diet administered with Phyllantin 14 by gavage for 6 weeks. Control mice were fed a standard diet without oxalate. No adverse effects were associated to Phyllantin 14 supplementation, supporting its safety. Mice fed a high-oxalate diet developed significant hyperoxaluria and those administered with Phyllantin 14 showed a reduced level of urinary oxalate and a lower oxalate-to-creatinine ratio. Soluble and insoluble caecal oxalate were significantly lower in treated group, a finding in agreement with the colonisation study, i.e. mice were colonised with SGL 14 after 3 weeks. Microbiota analysis demonstrated that both oxalate diet and Phyllantin 14 can differently modulate the microbiota. In conclusion, our findings suggest that Phyllantin 14 supplementation represents a potential supportive approach for reducing urinary oxalate and/or for enhancing the efficacy of existing treatments.


Assuntos
Dieta , Hiperoxalúria/terapia , Lactobacillus acidophilus , Oxalatos/administração & dosagem , Phyllanthus , Extratos Vegetais/uso terapêutico , Animais , Aderência Bacteriana , Ceco/química , Modelos Animais de Doenças , Fezes/química , Microbioma Gastrointestinal , Células HT29 , Humanos , Hiperoxalúria/tratamento farmacológico , Hiperoxalúria/patologia , Rim/patologia , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus acidophilus/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxalatos/análise , Oxalatos/urina , Fitoterapia , Probióticos
12.
Science ; 292(5524): 2060-3, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11337589

RESUMO

Colloidal quantum rods of cadmium selenide (CdSe) exhibit linearly polarized emission. Empirical pseudopotential calculations predict that slightly elongated CdSe nanocrystals have polarized emission along the long axis, unlike spherical dots, which emit plane-polarized light. Single-molecule luminescence spectroscopy measurements on CdSe quantum rods with an aspect ratio between 1 and 30 confirm a sharp transition from nonpolarized to purely linearly polarized emission at an aspect ratio of 2. Linearly polarized luminescent chromophores are highly desirable in a variety of applications.


Assuntos
Compostos de Cádmio , Luminescência , Compostos de Selênio , Semicondutores , Compostos de Cádmio/química , Fenômenos Químicos , Físico-Química , Coloides , Cristalização , Lasers , Luz , Microscopia Confocal , Microscopia Eletrônica , Microscopia de Fluorescência , Compostos de Selênio/química , Análise Espectral , Temperatura
13.
J Endocrinol Invest ; 32(2): 115-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19411807

RESUMO

RET mutations play an important role in the development of human neuroendocrine tumors. The prevalence of the RET polymorphism G691S of exon 11 is higher in patients with medullary thyroid carcinoma (MTC) as compared to the general population. A weak association between RET polymorphisms and sporadic papillary thyroid carcinoma (PTC) has also been described. We hereby describe the association of MTC, bronchial carcinoid tumor, and PTC in a familial setting. A 75-yr-old woman developed MTC 7 yr after successful treatment of a bronchial carcinoid. Serum calcitonin was 12.9 pg/ml with a peak response to pentagastrin (151.0 pg/ml). The patient underwent total thyroidectomy and a genetic mutational analysis of the RET gene. Histological evaluation confirmed MTC with no evidence of lymph nodes involvement. After thyroidectomy serum calcitonin was <2.0 pg/ml. A germline missense mutation at codon 691 in exon 11 of the RET gene was found. The mutational analysis was extended to the patient's offspring, and her daughter was found to bear the G691S polymorphism of RET. Wild type RET gene was found in the son. The daughter, who showed a nodular goiter, autoimmune thyroiditis and normal serum calcitonin, also underwent thyroidectomy. Histologic examination of the thyroid revealed an incidental PTC. This is the first description of a bronchial carcinoid tumor occurring in association with MTC. The occurrence of apparently unrelated NET in the same subject, or within a family, should be regarded as a challenge for deeper investigations into the possible oncogenic role of this genetic alteration.


Assuntos
Neoplasias Brônquicas/genética , Tumor Carcinoide/genética , Carcinoma Medular/genética , Carcinoma Papilar/genética , Neoplasias de Tecido Vascular/genética , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Idoso , Sequência de Bases , Análise Mutacional de DNA , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem , Polimorfismo Genético
14.
J Pharm Biomed Anal ; 48(2): 303-9, 2008 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-18243626

RESUMO

Pharmaceutical counterfeiting is a worldwide public health problem, often under-recognised, especially in developing countries where the percentage of counterfeit and sub-standard medicines is dramatically high. Antibiotics, among the most widespread drugs, have been particularly targeted by counterfeiters. World Health Organization emphasizes the need for development and distribution of screening methods explicitly targeted to counterfeit drugs. In this paper is presented a single method for the simultaneous analysis of some of the most common and counterfeited essential antibiotics: ampicillin, amoxicillin+clavulanic acid, doxycycline, cloxacillin, chloramphenicol. A full validation was performed in terms of linearity, precision, robustness and trueness; an assessment of uncertainty was carried out exploiting these data. A wide linearity range was investigated considering the specific nature of counterfeit and sub-standard drugs, whose content in active substance may be rather far from the declared amount. A large span in robustness parameters was considered and a complete intermediate precision assessment was conducted, envisaging the possibility of transferring the method to quality control laboratories, hopefully in developing countries. Finally, the method was successfully applied to the analysis of antibiotics purchased on the informal market in Chad, among which counterfeit and sub-standard samples were detected.


Assuntos
Antibacterianos/análise , Cromatografia Líquida/métodos , Antibacterianos/normas , Fraude
15.
Ecol Evol ; 8(12): 6124-6132, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29988435

RESUMO

The arroyo southwestern toad is a specialized and federally endangered amphibian endemic to the coastal plains and mountains of central and southern California and northwestern Baja California. It is largely unknown how long these toads live in natural systems, how their population demographics vary across occupied drainages, and how hydrology affects age structure. We used skeletochronology to estimate the ages of adult arroyo toads in seven occupied drainages with varying surface water hydrology in southern California. We processed 179 adult toads with age estimates between 1 and 6 years. Comparisons between skeletochronological ages and known ages of PIT tagged toads showed that skeletochronology likely underestimated toad age by up to 2 years, indicating they may live to 7 or 8 years, but nonetheless major patterns were evident. Arroyo toads showed sexual size dimorphism with adult females reaching a maximum size of 12 mm greater than males. Population age structure varied among the sites. Age structure at sites with seasonally predictable surface water was biased toward younger individuals, which indicated stable recruitment for these populations. Age structures at the ephemeral sites were biased toward older individuals with cohorts roughly corresponding to higher rainfall years. These populations are driven by surface water availability, a stochastic process, and thus more unstable. Based on our estimates of toad ages, climate predictions of extreme and prolonged drought events could mean that the number of consecutive dry years could surpass the maximum life span of toads making them vulnerable to extirpation, especially in ephemeral freshwater systems. Understanding the relationship between population demographics and hydrology is essential for predicting species resilience to projected changes in weather and rainfall patterns. The arroyo toad serves as a model for understanding potential responses to climatic and hydrologic changes in Mediterranean stream systems. We recommend development of adaptive management strategies to address these threats.

16.
J Mater Chem B ; 5(24): 4587-4594, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29308203

RESUMO

With the aim of producing Au-Fe x O y dimers with outstanding heating performances under magnetic hyperthermia conditions applicable to human patients, here we report two synthesis routes, a two-pot and a one-pot method. The addition of chloride ions and the absence of 1,2-hexadecanediol (HDDOL), a commonly used chemical in this synthesis, are the key factors that enable us to produce dimers at low temperature with crystalline iron oxide domains in the size range between 18-39 nm that is ideal for magnetic hyperthermia. In the case of two-pot synthesis, in which no chloride ions are initially present in the reaction pot, dimers are obtained only at 300 °C. In order to lower the reaction temperature to 200 °C and to tune the size of the iron oxide domain, the addition of chloride ions becomes the crucial parameter. In the one-pot method, the presence of chloride ions from the start of the synthesis (as counter ions of the gold salt precursor) enables a prompt formation of dimers directly at 200 °C. In this case, the reaction time is the main parameter used to tune the iron oxide size. A record value of specific absorption rates (SARs) up to 1300 W gFe-1 at 330 kHz and 24 kA m-1 was measured for dimers with an iron oxide domain of 24 nm in size.

17.
Vet Parasitol ; 142(1-2): 142-5, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-16884851

RESUMO

A 2-year field study on kennelled stray dogs living in a highly endemic area of leishmaniasis was designed to evaluate whether deltamethrin-impregnated collars (Scalibor) Protector Band) could confer protection against leishmaniasis in this peculiar setting, and to assess differences in clinical outcomes between collared and uncollared dogs. A cohort of 120 clinically healthy and Leishmania-seronegative dogs was enrolled, 50% of which were collared before the 2003 transmission season, and then re-collared before the subsequent season. Collared and uncollared animals were allowed to live with infected dogs in same groups within the kennel. Follow-up included serological (IFAT) assessment twice a year with parasitological Leishmania confirmation, and clinical evaluation performed every 3 months on seroconverted dogs from both groups. Collar losses during the two seasons were high (35%). About 50% of enrolled dogs were lost at follow-up because of death or they were moved to other locations. After the 2003 season, cross-sectional serological examinations tested positive in 5 out of 44 collared animals (11.4%) and in 14 out of 34 controls (41.2%), with 72.3% estimated protection (P<0.005). After the 2004 season, 7/31 seronegative collared dogs seroconverted (22.6%) compared with 7/17 seronegative controls (41.2%), with 45.1% protection (P=0.15). At the end of the study, the cumulative rate of protection was 50.8% (P=0.005). At the clinical evaluation of 21 seroconverted dogs from both groups, canine leishmaniasis signs were significantly more frequent (90% versus 36%, P=0.017) and rapidly progressive in uncollared than in collared dogs. Reasons for such partial clinical protection in collared dogs may be found in the vector anti-feeding effect of protector bands, resulting in a lower number of infectious bites and, probably, in the reduction of antigenic stimuli necessary to shift toward a non-protective immune response.


Assuntos
Doenças do Cão/prevenção & controle , Inseticidas/farmacologia , Leishmaniose/veterinária , Nitrilas/farmacologia , Phlebotomus/parasitologia , Piretrinas/farmacologia , Animais , Estudos de Coortes , Doenças do Cão/transmissão , Cães , Feminino , Mordeduras e Picadas de Insetos/prevenção & controle , Mordeduras e Picadas de Insetos/veterinária , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/parasitologia , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/transmissão , Leishmaniose Visceral/veterinária , Masculino , Phlebotomus/efeitos dos fármacos , Estações do Ano , Resultado do Tratamento
18.
Biosens Bioelectron ; 21(1): 30-40, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15967348

RESUMO

In this paper we have tested two different procedures (the "three-step" and the "four-step" procedures) for the covalent immobilization of glutamate dehydrogenase (GDH) onto silicon supports. Atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), fluorescence spectroscopy and an enzymatic assay were used to probe the structure and activity of the immobilized enzyme. Our results demonstrate that coupling through the "three-step" procedure does not significantly affect either the fold pattern or the activity of the enzyme, suggesting that this method could be ideally suited to the development of high quality monolayers for use in enzyme-based planar biosensors.


Assuntos
Técnicas Biossensoriais/instrumentação , Enzimas Imobilizadas , Glutamato Desidrogenase , Silício , Microscopia de Força Atômica , NAD/metabolismo , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier
19.
J Pharm Biomed Anal ; 39(3-4): 463-8, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15927432

RESUMO

A simple and rapid open-vessel focused microwave-assisted extraction (FMAE) method followed by LC analysis was developed for the determination of naproxen in suppositories. Parameters which might affect the FMAE method, such as nature and volume of the extraction solvent, temperature and extraction time were optimized. The extraction solvent consisted of methanol/sodium hydrogen carbonate (pH 8.7; 0.1 M) (50:50, v/v). Extractions were performed by reaching the target temperature of 70 degrees C in a 7 min linear ramp and then maintaining the target temperature for 3 min. Chromatographic analysis was performed on a Discovery RP-Amide C16 column (250 mm x 4.6 mm i.d., 5 microm particle size). The mobile phase consisted of acetonitrile/potassium dihydrogenphosphate (pH 3.0; 25 mM) (40:60, v/v). The complete analytical procedure was validated with regard to limit of quantification, linearity, precision and accuracy. The advantages of the proposed method in comparison to conventional methods are decreased extraction time, reduced solvent consumption and no further sample clean-up steps required before liquid chromatographic analysis.


Assuntos
Anti-Inflamatórios não Esteroides/química , Cromatografia Líquida/métodos , Indústria Farmacêutica/métodos , Micro-Ondas , Naproxeno/química , Supositórios/química , Química Farmacêutica/métodos , Cromatografia , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Fosfatos/química , Compostos de Potássio/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Temperatura , Fatores de Tempo
20.
Obes Surg ; 10(1): 15-21, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10715638

RESUMO

BACKGROUND: The laparoscopic technique for the Swedish Adjustable Gastric Band (SAGB) has been developed based on the previously established open technique. METHODS: From March 1996-June 1997, laparoscopic SAGB was attempted in 85 consecutive obese patients (77 women and 8 men). The average preoperative BMI was 44 (34-59). RESULTS: All operations except one were completed by laparoscopy. One patient had to be converted because of unfavorable anatomic conditions. The average operating time was 40 minutes. There were no immediate perioperative complications. All patients were followed for 1 year. During this period 2 patients developed esophagitis and 3 patients experienced repeated vomiting. There were no other complications. At 1 year follow-up the average BMI was 33 (21-46). The excess weight loss was 54% (17-100%). CONCLUSION: Early results are encouraging. No significant complications related to the technique were registered. One-year weight loss was equal to what was achieved by open surgery. Laparoscopic SAGB will be established as an attractive alternative for surgical treatment of morbid obesity.


Assuntos
Gastroplastia/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Adolescente , Adulto , Feminino , Gastroplastia/efeitos adversos , Gastroplastia/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Redução de Peso
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa