Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
1.
Reumatismo ; 76(1)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38523582

RESUMO

OBJECTIVE: To report cross-sectionally serum levels of 25-hydroxyvitamin D [25(OH)D] in women living in Italy within 12 months from breast cancer (BC) diagnosis. METHODS: Baseline data were obtained from 394 women diagnosed with primary BC, enrolled from 2016 to 2019 in a lifestyle trial conducted in Italy. Subjects' characteristics were compared between two 25(OH)D concentrations (hypovitaminosis D<20 and ≥20 ng/mL) with the Chi-squared test or Fisher's exact test for small-expected counts. Using multiple logistic regression-adjusted models, we estimated odds ratios (ORs) of hypovitaminosis D with 95% confidence intervals (CIs) in the total sample and in the unsupplemented subgroup. RESULTS: Hypovitaminosis D was found in 39% of all subjects, 60% in unsupplemented subjects, and 10% in supplemented subjects. Increasing ORs of hypovitaminosis D were found with increasing body mass index, 25-30, >30, and ≥35 versus <25 kg/m2 (ORs: 2.50, 4.64, and 5.81, respectively, in the total cohort and ORs: 2.68, 5.38, and 7.08 in the unsupplemented); living in the most southern Italian region (OR 2.50, 95%CI 1.22-5.13); and with hypertriglyceridemia (OR 2.46; 95%CI 1.16-5.22), chemotherapy history (OR 1.86, 95%CI 1.03-3.38), and inversely with anti-estrogenic therapy (OR 0.43, 95%CI 0.24-0.75) in the total sample. CONCLUSIONS: Hypovitaminosis D in women recently diagnosed with BC and participating in a lifestyle trial in Italy was widespread and highest with obesity, hypertriglyceridemia, and chemotherapy use. Considering that hypovitaminosis D is a risk factor for lower efficacy of bone density treatments and possibly BC mortality, our results suggest the need to promptly address and treat vitamin D deficiency.


Assuntos
Neoplasias da Mama , Hipertrigliceridemia , Deficiência de Vitamina D , Vitamina D , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/complicações , Hipertrigliceridemia/complicações , Itália/epidemiologia , Estilo de Vida , Fatores de Risco , Vitamina D/análogos & derivados , Deficiência de Vitamina D/epidemiologia
2.
Eur Rev Med Pharmacol Sci ; 26(1 Suppl): 53-59, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36448856

RESUMO

OBJECTIVE: Hip arthroplasty is one of the most performed surgeries in orthopedics. Rehabilitation process after surgery allows rapid recovery of joint functions in absence of pain in most patients. During COVID-19 pandemic, rehabilitation clinics have reduced the number of beds available. Thus, an increasing number of patients were forced to home rehabilitation programs. Our study aimed at determining any significant differences in clinical and functional outcomes between those patients who underwent a home rehabilitation program and those others who were granted a place in a Rehabilitation clinic during COVID-19 pandemic, at mid-term follow-up. PATIENTS AND METHODS: An observational retrospective single-center study was designed. The patients included were 63, divided into two groups: Group A (29 patients) for home rehabilitation, and Group B (34 patients) for clinic rehabilitation. Follow-up was performed at 1, 6 and 12 months after surgery. Clinical evaluation was assessed through Oxford Hip Score for hip function, Visual Analogue Scale (VAS) for pain and hip range of motion (ROM) to evaluate joint recovery. RESULTS: ROM was compared at follow-up with significant differences 12 months after surgery (107.93° group A vs. 104.7° group B; p=0.0168). Pain felt by patients according to the VAS scale showed no significant differences at follow-up (1 month 3.27 vs. 3.65 p=0.1489; 6 months 1.89 vs. 2.18 p=0.105; 12 months 0.58 vs. 0.68 p=0.6263). Regarding the Oxford Hip score, significant differences emerged at 1-month follow-up (38.75 group A vs. 37.94 group B; p=0.0498). CONCLUSIONS: At mid-term follow-up, little differences were found between patients who went through home rehabilitation and those who went to a rehabilitation clinic. Therefore, decreasing the number of beds available in rehab clinics during COVID-19 pandemic was not an obstacle for elective surgery for orthopedic surgeons.


Assuntos
Artroplastia de Quadril , COVID-19 , Humanos , Estudos Retrospectivos , Controle de Doenças Transmissíveis , Dor
3.
Eur Rev Med Pharmacol Sci ; 26(1 Suppl): 106-112, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36448862

RESUMO

OBJECTIVE: Massive bone loss is a serious problem in the elderly. Joint replacement with modular prostheses represents the most common reconstructive technique after oncological and non-oncological resections. Megaprostheses are broadly available, adaptable and versatile and allow early mobilization and rehabilitation. Although segmental endoprosthetic implants are now widely used and despite innovations, complications remain far high. Our purpose is to establish what happens to megaprostheses of a specific anatomical site in the long term in a population with oncologic and non-oncologic indications treated at a single center solely by a few skilled surgeons. MATERIALS AND METHODS: We retrospectively reviewed our institutional database. We collected 35 patients who underwent endoprosthetic reconstruction exclusively of the proximal femur for neoplastic and non-neoplastic disease between 2008 and 2021. The minimum follow-up was 12 months. Complications were collected and classified, and also adapted to the non-oncological setting. RESULTS: Taking into consideration the entire population, 94% of this survived the follow-up at 6 months, subsequently 85% at 1 year and 82% at 2 years. At follow-ups after 5 years, 79% of megaprostheses showed no mechanical failure. Analyzing prosthetic survival in the two groups, this was >50% at 24 months after surgery in both groups, with better survival for the oncological one. CONCLUSIONS: Proximal femur replacement can be a valid option in treatment of oncological and non-oncological cases. Due to the high complication rate, only selected cases should undergo this kind of surgical procedure.


Assuntos
Extremidade Inferior , Sobrevivência , Idoso , Humanos , Estudos Retrospectivos , Fêmur/cirurgia , Artéria Femoral
4.
Eur Rev Med Pharmacol Sci ; 26(1 Suppl): 100-105, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36448865

RESUMO

OBJECTIVE: The humerus is the second long bone most affected by pathological fractures. According to Capanna and Campanacci criteria, surgical choice is based on bone metastasis location, on the patient's status and on the residual functional capacity. Metadiaphysis is an area of conflict in the choice between megaprosthesis implant and intramedullary nail osteosynthesis. This study compares these two surgical procedures in terms of reacquired functionality and local control of metastasis. PATIENTS AND METHODS: Thirty-eight patients (17 males and 21 females; mean age: 66 years old) treated in our institution between January 2010 and December 2020 for pathological humeral metadiaphyseal fractures caused by metastasis, were included in this study. We choose the Musculoskeletal Tumor Society rating system (MSTS) and the Quick Disability of Arm-Shoulder-Hand (QuickDASH) scores for the evaluation of the upper limb function after surgery. RESULTS: Eighteen (47%) pathological fractures were treated by resection and megaprosthesis implantation, twenty (53%) were treated by medullary nail osteosynthesis. A reduction in pain and greater mechanical stability in the immediate post-operative period was found in all patients. Twenty-two patients died (58%) and sixteen survived (42%). Long-term functional recovery of patients undergoing osteosynthesis is greater than megaprothesis group. CONCLUSIONS: Both medullary nail osteosynthesis and resection and megaprosthesis implantation guarantee excellent recovery at 72 months after surgery, improvement in quality of life and pain relief.  Patients treated with osteosynthesis showed a great short-term functional recovery since the joint portion of the limb is not involved, whereas patients treated with megaprosthesis showed better local oncologic control. It is therefore possible to define the type of treatment not only on the localization of the fracture (diaphysis or epiphysis) but above all on the conditions and characteristics of the patient.


Assuntos
Neoplasias Ósseas , Fraturas Ósseas , Fraturas Espontâneas , Adulto , Feminino , Masculino , Humanos , Idoso , Ombro , Fraturas Espontâneas/cirurgia , Qualidade de Vida , Úmero , Epífises , Neoplasias Ósseas/cirurgia , Extremidade Superior , Dor
5.
Microbiol Spectr ; 10(6): e0289322, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36222693

RESUMO

Mycobacterium chimaera is ubiquitously spread in the environment, including factory and hospital water systems. Invasive cases of M. chimaera infection have been associated with aerosols produced by the use of heater-cooler units (HCU) during cardiac surgery. The aim of this study was to evaluate for the first time the performance of IR-Biotyper system on a large number of M. chimaera isolates collected from longitudinal environmental HCUs samples and water sources from hospitals located in three Italian provinces. In addition, IR-Biotyper results were compared with whole-genome sequencing (WGS) analysis, the reference method for molecular epidemiology, to investigate the origin of M. chimaera contamination of HCUs. From November 2018 to May 2021, 417 water samples from 52 HCUs (Stockert 3T, n = 41 and HCU40, n = 11) and 23 hospital taps (used to fill the HCU tanks) were concentrated, decontaminated, and cultured for M. chimaera. Positive cultures (n = 53) were purified by agar plate subcultures and analyzed by IR-Biotyper platform and Ion Torrent sequencing system. IR-Biotyper spectra results were analyzed using a statistical approach of dimensionality reduction by linear discriminant analysis (LDA), generating three separate clusters of M. chimaera, ascribable to each hospital. Furthermore, the only M. chimaera-positive sample from tap water clustered with the isolates from the HCUs of the same hospital, confirming that the plumbing system could represent the source of HCU contamination and, potentially, of patient infection. According to the genome-based phylogenies and following the classification proposed by van Ingen and collaborators in 2017, three distinct M. chimaera groups appear to have contaminated the HCU water systems: subgroups 1.1, 2.1, and branch 2. Most of the strains isolated from HCUs at the same hospital share a highly similar genetic profile. The nonrandom distribution obtained with WGS and IR-Biotyper leads to the hypothesis that M. chimaera subtypes circulating in the local plumbing colonize HCUs through the absolute filter, in addition with the current hypothesis that contamination occurs at the HCU production site. This opens the possibility that other medical equipment, such as endoscope reprocessing device or hemodialysis systems, could be contaminated by M. chimaera. IMPORTANCE Our manuscript focuses on interventions to reduce waterborne disease transmission, improve sanitation, and control infection. Sanitary water can be contaminated by nontuberculous Mycobacteria, including M. chimaera, a causative agent of invasive infections in immunocompromised patients. We found highly similar genetic and phenotypic profiles of M. chimaera isolated from heater-cooler units (HCU) used during surgery to thermo-regulate patients' body temperature, and from the same hospital tap water. These results lead to the hypothesis that M. chimaera subtypes circulating in the local plumbing colonize HCUs through the absolute filter, adding to the current hypothesis that contamination occurs at the HCU production site. In addition, this opens the possibility that other medical equipment using sanitized water, such as endoscope reprocessing devices or hemodialysis systems, could be contaminated by nontuberculous Mycobacteria, suggesting the need for environmental surveillance and associated control measures.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Infecções por Mycobacterium , Mycobacterium , Humanos , Infecções por Mycobacterium/epidemiologia , Infecções por Mycobacterium/microbiologia , Infecções por Mycobacterium/prevenção & controle , Espectroscopia de Infravermelho com Transformada de Fourier , Mycobacterium/genética , Complexo Mycobacterium avium , Contaminação de Equipamentos , Infecções por Mycobacterium não Tuberculosas/microbiologia
6.
Sci Rep ; 12(1): 9223, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654982

RESUMO

We report pump-probe transient absorption measurements addressing the photocycle of the Germanium lone pair center (GLPC) point defect with an unprecedented time resolution. The GLPC is a model point defect with a simple and well-understood electronic structure, highly relevant for several applications. Therefore, a full explanation of its photocycle is fundamental to understand the relaxation mechanisms of such molecular-like systems in solid state. The experiment, carried out exciting the sample resonantly with the ultraviolet (UV) GLPC absorption band peaked at 5.1 eV, gave us the possibility to follow the defect excitation-relaxation dynamics from the femto-picosecond to the nanosecond timescale in the UV-visible range. Moreover, the transient absorption signal was studied as a function of the excitation photon energy and comparative experiments were conducted on highly- and weakly-germanium doped silica glasses. The results offer a comprehensive picture of the relaxation dynamics of GLPC and allow observing the interplay between electronic transitions localized on the defect and those related to bandgap transitions, providing a clear evidence that the role of dopant high concentration is not negligible in the earliest dynamics.


Assuntos
Germânio , Fótons , Dióxido de Silício
7.
Phys Chem Chem Phys ; 24(21): 12974-12983, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35582872

RESUMO

In recent times, nanoscience is devoting growing interest to the easy assembly of well-established nanomaterials into hybrid nanostructures displaying new emerging features. Here, we study the photophysicochemical response of binary nanohybrids obtained by the spontaneous coupling of luminescent carbon dots to silver nanoparticles with controlled surface charge. Evidence of the successful coupling is obtained by steady-state and time resolved optical measurements and further confirmed by direct imaging. We demonstrate strong interactions within nanohybrids, which can be modelled in terms of a sub-picosecond electron transfer from photoexcited carbon dots to silver nanoparticles. Accordingly, newly designed nanohybrids display significant photocatalytic performance demonstrated by the photodegradation of methylene blue under ultraviolet-visible light. Our results provide an exhaustive picture of the optical response of these self-assembled carbon-silver nanohybrids and show their promise as a new class of eco-friendly materials for light-driven catalytic applications.

8.
Am J Clin Dermatol ; 22(4): 567-579, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33786754

RESUMO

BACKGROUND: Drug survival analysis of biologic agents in psoriasis is of extreme importance, as it allows not only the evaluation of objective clinical outcomes (such as effectiveness and safety) but also of factors that are associated with patients' adherence to treatment. The aim of this study was to evaluate and compare the drug survival of the most recent biologic agents approved for the treatment of moderate-to-severe psoriasis-ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab, and risankizumab-and to identify clinical predictors that can influence the drug survival of these drugs. METHODS: This retrospective multicentric cohort study from 16 dermatology centers in Portugal, Spain, Italy, Switzerland, Czech Republic, Canada, and the United States included patients that started IL-12/23, IL-17 (IL-17A and IL-17R) and IL-23 inhibitors for the treatment of psoriasis between January 1, 2012 and December 31, 2019. Survival analysis was performed using a Kaplan-Meier estimator, to obtain descriptive survival curves, and proportional hazard Cox regression models. RESULTS: A total of 3312 treatment courses (total patients: 3145) were included in the study; 1118 (33.8%) with an IL-12/23 inhibitor (ustekinumab), 1678 (50.7%) with an IL-17 inhibitor [911 (27.5%) on secukinumab, 651 (19.7%) on ixekizumab, 116 (3.5%) on brodalumab], and 516 (15.5%) with an IL-23 inhibitor [398 (12.0%) on guselkumab, 118 (3.5%) on risankizumab]. At 18 months, the cumulative probability of survival was 96.4% for risankizumab, 91.1% for guselkumab, 86.3% for brodalumab, 86.1% for ustekinumab, 82.0% for ixekizumab, and 79.9% for secukinumab. Using ustekinumab as reference, drug survival of guselkumab was higher (HR 0.609; 95% CI 0.418-0.887) and that of secukinumab was lower (HR 1.490; 95% CI 1.257-1.766). In the final multivariable model, secukinumab, female sex, higher BMI, and prior exposure to biologic agents significantly increased the risk of drug discontinuation, whereas risankizumab was protective. CONCLUSION: In this multinational cohort with 8439 patient-years of follow-up, the cumulative probability of drug survival for all drugs was >79% at 18 months. Prescribed biologic, female sex, higher BMI, and previous exposure to biologic agents were predictors of drug discontinuation. Drug survival of guselkumab and risankizumab was higher than that of ustekinumab, and secukinumab was lower.


Assuntos
Produtos Biológicos/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Idoso , Produtos Biológicos/farmacologia , Fármacos Dermatológicos/farmacologia , Feminino , Seguimentos , Humanos , Interleucina-12/antagonistas & inibidores , Interleucina-12/imunologia , Interleucina-17/antagonistas & inibidores , Interleucina-17/imunologia , Interleucina-23/antagonistas & inibidores , Interleucina-23/imunologia , Masculino , Pessoa de Meia-Idade , Psoríase/imunologia , Indução de Remissão/métodos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
9.
Phys Chem Chem Phys ; 22(24): 13398-13407, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32377658

RESUMO

Carbon dots are a family of optically-active nanoparticles displaying a combination of useful properties that make them attractive for many applications in photonics and photochemistry. Despite the initial claims of high photostability of carbon dots even under prolonged illuminations, several recent studies have evidenced their photobleaching (PB) under UV light, detrimental for some applications. A study of the mechanism and dynamics of carbon dot PB can be considered a useful route to gather relevant information on the underlying photophysics of these nanoparticles, which is still widely debated. Here we report a study of the PB of carbon dots under UV light, conducted through optical experiments under well-controlled illumination conditions. In particular, the use of a laser as an irradiation source allows a precise control of the irradiated volume, and provides accurate estimates and control of the administered energy. Besides, our setup allows spectroscopic measurements to be carried out in situ at the irradiated site, thus allowing us to investigate in real time the progress of photobleaching effects through a time-resolved approach. Therefore, our experiments allow the precise kinetics of the undergoing PB process to be captured which is found to be significantly affected by disorder and photoselection effects. Furthermore, our study discloses several pieces of information on the nature of the main blue chromophore absorbing at 340 nm and emitting at 430 nm, and on its PB mechanism. We propose that the emissive units consist in small molecular-like chromophores adsorbed on carbon dot surfaces and are in a dynamical equilibrium with free diffusing molecules in solution. Their photobleaching proceeds in two distinct steps: in the first phase, linear absorption of UV photons rapidly converts the molecular surface chromophores into a non-emissive form, likely through an isomerization, causing the disappearance of the fluorescence properties but almost no changes in the optical absorption spectra. At higher fluences, a complete destruction of the optically-active centers is observed, which completely wipes out all the absorption features of surface chromophores and only leaves a fully carbonized, yet non-fluorescent, dot core.

12.
Med Mycol ; 58(1): 22-29, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874811

RESUMO

Paracoccidioidomycosis (Pm) is a systemic disease, endemic in the American continent. There are two different clinical forms, the infant-juvenile or subacute form (PmS) and the chronic adult form (PmC). The human immunodeficiency virus (HIV) associated paracoccidioidomycosis (PmHIV) shares characteristics with both of the previously mentioned forms. The objective of this work was to describe the epidemiological, clinical and laboratory features of the PmHIV and to compare them with the ones of PmS and the PmC. A retrospective analysis of 119 patients with paracoccidioidomycosis was performed. Ninety four suffered the chronic form, 11 the subacute one and 14 were coinfected with HIV. Patients with PmHIV presented a CD4+ T lymphocytes median of 70.5 cells/µl, 71.4% had fever, 64.3% had a miliary pattern on the chest radiography, 64.3% had hepatosplenomegaly, 64.3% had mucosal lesions and 50% had skin lesions. One patient died during his hospitalization. The clinical presentation of Pm in patients with HIV resembled the subacute form with fever, hepatomegaly and skin lesions. However, they also tended to present mucosal lesions, positive serology for Pm and pulmonary parenchyma lesions as usually seen in PmC (9/14 PmHIV patients had overlapping features, while 4/14 PmHIV patients clinically resembled PmS and 1/14 PmC). The incidence of Pm has not changed with the burden of AIDS as it has happened with other fungal infections but it appears clinically different from the classic clinical forms of the disease.


Assuntos
Síndrome de Imunodeficiência Adquirida/complicações , Síndrome de Imunodeficiência Adquirida/microbiologia , Paracoccidioidomicose/microbiologia , Adulto , Antifúngicos/uso terapêutico , Argentina/epidemiologia , Linfócitos T CD4-Positivos , Feminino , Febre/microbiologia , Infecções por HIV/microbiologia , Hepatomegalia/microbiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/epidemiologia , Radiografia , Estudos Retrospectivos , Tórax/diagnóstico por imagem , Tórax/microbiologia
13.
Prensa méd. argent ; 104(10): 510-515, dic 2018. graf, tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1046997

RESUMO

La criptococosis es una micosis grave de distribución universal, que afecta principalmente a huéspedes inmunocomprometidos. Es una de las principales causas de morbilidad y mortalidad en los pacientes infectados con el virus de la inmunodeficiencia humana (HIV). Provoca al menos 620 000 muertes al año, representando entre el 13% al 44% de la mortalidad en pacientes HIV positivos según datos de cohortes correspondientes a países en desarrollo. (1, 2) La letalidad de la criptococosis meníngea en estudios de Argentina y Brasil muestra valores que van desde el 26% hasta el 63%. El complejo Cryptococcus neoformans/ Cryptococcus gattii, es el responsable de esta enfermedad. Existen alrededor de 70 especies pero solo dos de ellas son patógenas para el hombre: C. neoformans y C. gattii. Se reconocen 8 genotipos de este complejo, C. neoformans: VNI y VNII (C. neoformans var. grubii), VNIII (C. neoformans híbrido intervariedad AD), VNIV (C. neoformans var. neoformans) y C. gattii: genotipos VGI, VGII, VGIII y VGIV. Se han descripto híbridos interespecie VNIV/VGI, VNI/VGI, VNI/VGII. Se estudiaron 207 aislamientos de Cryptococcus, elegidos aleatoriamente, de un total de 2593 pacientes con diagnóstico de criptococosis diseminada. A los mismos se les realizó la genotipificación mediante una PCR-RFLP del gen URA5, y posterior digestión enzimática con enzimas Sau96I y HhaI. De las 207 cepas estudiadas, 174 fueron VNI (84,05%), 14 VNII (6,76%), 10 VNIII (4,83%), 2 VNIV (0,97%), 3 VGI (1,45%), 3 VGII de (1,45%) y 1 VGIII (0,49%).


Cryptococcosis is a severe worldwide mycosis, which mainly affects immunocompromised hosts and is a major cause of morbidity and mortality in HIV-infected patients. It causes 620,000 annual deaths, accounting for 13-44 % of mortality in HIV-positive individuals in developing countries. Mortality rates of meningeal cryptococcosis in studies from Argentina and Brazil go from 26 to 63 %. Cryptococcus neoformans/Cryptococcus gattii is the species complex responsible for this disease. There are about 70 species, however, only two are human pathogens: C. neoformans and C. gattii. C. neoformans genotypes are VNI and VNII (C. neoformans var. grubii), VNIII (C. neoformans intervariety hybrid AD), VNIV (C. neoformans var. neoformans). C. gattii genotypes are VGI, VGII, VGIII and VGIV. Interspecies hybrids were described: VNIV/VGI, VNI/VGI, VNI/ VGII. A total of 207 Cryptococcus isolates were randomly selected from 2593 patients with diagnosis of disseminated cryptococcosis. Genotyping was performed by PCRRFLP of UR A5 gene with restriction enzyme digestion using Sau96I and HhaI enzymes. Among the 207 studied isolates, 174 resulted VNI (84.05%), 14 VNII (6.76%), 10 VNIII (4.83%), 2 VNIV (0.97%), 3 VGI (1.45%), 3 VGII (1.45%) and 1 VGIII (0.49%).


Assuntos
Humanos , Estudos Transversais/estatística & dados numéricos , Morbidade , HIV/isolamento & purificação , Meningite Criptocócica/epidemiologia , Cryptococcus neoformans/isolamento & purificação , Cryptococcus gattii/isolamento & purificação , Genótipo
14.
J Evol Biol ; 31(2): 302-313, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29220874

RESUMO

Resource competition is frequently strong among parasites that feed within small discrete resource patches, such as seeds or fruits. The properties of a host can influence the behavioural, morphological and life-history traits of associated parasites, including traits that mediate competition within the host. For seed parasites, host size may be an especially important determinant of competitive ability. Using the seed beetle, Callosobruchus maculatus, we performed replicated, reciprocal host shifts to examine the role of seed size in determining larval competitiveness and associated traits. Populations ancestrally associated with either a small host (mung bean) or a large one (cowpea) were switched to each other's host for 36 generations. Compared to control lines (those remaining on the ancestral host), lines switched from the small host to the large host evolved greater tolerance of co-occurring larvae within seeds (indicated by an increase in the frequency of small seeds yielding two adults), smaller egg size and higher fecundity. Each change occurred in the direction predicted by the traits of populations already adapted to cowpea. However, we did not observe the expected decline in adult mass following the shift to the larger host. Moreover, lines switched from the large host (cowpea) to the small host (mung bean) did not evolve the predicted increase in larval competitiveness or egg size, but did exhibit the predicted increase in body mass. Our results thus provide mixed support for the hypothesis that host size determines the evolution of competition-related traits of seed beetles. Evolutionary responses to the two host shifts were consistent among replicate lines, but the evolution of larval competition was asymmetric, with larval competitiveness evolving as predicted in one direction of host shift, but not the reverse. Nevertheless, our results indicate that switching hosts is sufficient to produce repeatable and rapid changes in the competition strategy and fitness-related traits of insect populations.


Assuntos
Evolução Biológica , Besouros/crescimento & desenvolvimento , Comportamento Competitivo , Interações Hospedeiro-Parasita , Animais , Feminino , Fertilidade , Larva , Masculino , Seleção Genética
15.
Prensa méd. argent ; 103(7): 394-400, 20170000. tab, fig
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1372368

RESUMO

La Paracoccidioidomicosis es la micosis endémica más frecuente en América latina en enfermos HIV negativos. Objetivo: analizar las características clínicas, epidemiológicas, evolución y tratamiento de los pacientes con diagnóstico de paracoccidioidomicosis asistidos en un hospital de referencia en enfermedades infecciosas en un período de 10 años. Materiales y métodos: Estudio descriptivo y retrospectivo. Se analizaron las historias clínicas de 70 pacientes con diagnóstico de paracoccidioidomicosis en el período comprendido entre Enero de 2001 y Diciembre de 2010. Resultados: se incluyeron 70 pacientes. Cincuenta y nueve presentaron la forma crónica de la enfermedad, siete la infanto-juvenil y solo cuatro resultaron positivos para el HIV. La mayoría de los enfermos fueron de nuestro país y habían nacido en Chaco y Misiones. Veintiséis eran oriundos de Paraguay. El 81,4% de los casos tuvieron compromiso pulmonar y el patrón radiológico hilio-fugal, en "alas de mariposa", fue el más frecuente. Se observaron lesiones cutáneo-mucosas en 38,57% de los enfermos. El examen directo en fresco de esputo y la escarificación de las lesiones mucocutáneas resultó ser la prueba más útil para el diagnóstico de esta micosis endémica. La serología fue positiva en el 81,3 % de los pacientes con formas crónicas y en el 42,8% de la forma infanto-juvenil. La mayoría de los enfermos fueron tratados con itraconazol; sólo dos fallecieron. Conclusión: El diagnóstico de la paracoccidioidomicosis se basa principalmente en el examen microscópico directo; los cultivos de muestras clínicas pueden fallar. La paracoccidioidomicosis debe incluirse en el diagnóstico diferencial de los pacientes que provengan de áreas endémicas y presenten compromiso de piel, mucosas o del aparato respiratorio asociado a un síndrome infeccioso inespecífico


Paracoccidioidomycosis is the most frequent endemic mycosis in Latin America in HIV negative patients. Objective: to analyze the clinical, epidemiological and treatment characteristics and the evolution of patients with diagnosis of paracoccidioidomycosis. Materials and methods: Descriptive and retrospective study. The clinical records of 70 patients with paracoccidioidomycosis were analyzed in the period between January 2001 and December 2010. Results: 70 patients were included. Fifty-nine presented the chronic form, seven had the juvenile (acute) clinical picture and only four were HIV positive. The majority of the Argentinian patients had been born in Chaco and Misiones provinces. Twenty-six were from Paraguay. 81.4% of the patients had lung involvement, the "butterfly wing" pattern was the most frequent. Muco cutaneous lessions were observed in 38.57% of the patients. Wet mount microscopy examination of sputum and mucocutaneous scarification proved to be the most useful tests for the disease diagnosis Serology tests were positive in 81.3% of patients with the chronic form and in 42.8% of those with the juvenile clinical presentation. Most of the patients were treated with itraconazole. Only two deceased. Conclusion: The diagnosis of paracoccidiodomycosis is mainly based on direct microscopic examination of clinical smears. Cultures of clinical samples may fail. Paracoccidioidomycosis should be included in the differential diagnosis of patients who come from the endemic area and present skin, mucous membranes or respiratory system compromise associated with a non-specific infectious syndrome


Assuntos
Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Paracoccidioidomicose/terapia , Epidemiologia Descritiva , Estudos Retrospectivos , HIV/imunologia , Itraconazol/uso terapêutico , Doenças Endêmicas/prevenção & controle , Micoses/terapia , Diagnóstico Diferencial
16.
Phys Chem Chem Phys ; 19(34): 22670-22677, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28812086

RESUMO

The photoluminescence behaviour of carbon-based nanodots is still debated. Both core and surface structures are involved in the emission mechanism, and the electronic transitions can be modified by external agents such as metal ions or pH, but the general relation between the structure and the optical function is poorly understood. Here, we report a comparative study on the effects of these variables, changing the core structure from crystalline to amorphous, and modifying the surface structure by different passivation procedures. Our results highlight that the emission mechanism of the tunable visible fluorescence is identical for crystalline and amorphous samples, indicating the independence of the emission from the core structure. Furthermore, surface functionalization weakly influences the emission peak position, but has large consequences on their interaction with different metal ions. This suggests the involvement of quasi-degenerate electronic states originating from the high density of different interacting groups on the surface. Finally, we report the presence of an unusual ultraviolet emission band for the amorphous sample, likely involving localized molecular-type chromophores with carboxyl ends. Our findings provide new information on the emission mechanisms of CDs and can be used to engineer sub-types of CDs displaying very similar emission features, but specifically tailored for different sensing applications.

17.
Nanoscale ; 9(33): 11902-11911, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28660936

RESUMO

Fluorescent carbon nanodots are a novel family of carbon-based nanoscale materials endowed with an outstanding combination of properties that make them very appealing for applications in nanosensing, photonics, solar energy harvesting and photocatalysis. One of the remarkable properties of carbon dots is their strong sensitivity to the local environment, especially to metal ions in solution. These interactions provide a testing ground for their marked photochemical properties, highlighted by many studies, and frequently driven by charge transfer events. Here we combine several optical techniques, down to femtosecond time resolution, to understand the interplay between carbon nanodots and aqueous metal ions such as Cu2+ and Zn2+. We find that copper inhibits the fluorescence of carbon dots through static and diffusional quenching mechanisms, and our measurements allow discriminating between the two. Ultrafast optical methods are then used to address the dynamics of copper-dot complexes, wherein static quenching takes place, and unveil the underlying complexity of their photocycle. We propose an initial increase of electronic charge on the surface of the dot, upon photo-excitation, followed by a partial electron transfer to the nearby ion, with 0.2 ps and 1.9 ps time constants, and finally a very fast (≪1 ps) non-radiative electron-hole recombination which brings the system back to the ground state. Notably, we find that the electron transfer stage is governed by an ultrafast water rearrangement around photo-excited dots, pointing out the key role of solvent interactions in the photo-physics of these systems.

18.
Clin Radiol ; 72(10): 904.e11-904.e20, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28506798

RESUMO

AIM: To assess observer reliability and diagnostic accuracy in children, of a semi-automated six-point technique developed for vertebral fracture (VF) diagnosis in adults, which records percentage loss of vertebral body height. MATERIALS AND METHODS: Using a semi-automated software program, five observers independently assessed T4 to L4 from the lateral spine radiographs of 137 children and adolescents for VF. A previous consensus read by three paediatric radiologists using a simplified algorithm-based qualitative technique (i.e., no software involved) served as the reference standard. RESULTS: Of a total of 1,781 vertebrae, 1,187 (67%) were adequately visualised according to three or more observers. Interobserver agreement in vertebral readability for each vertebral level for five observers ranged from 0.05 to 0.47 (95% CI: -0.19, 0.76). Intra-observer agreement using the intraclass correlation coefficient (ICC) ranged from 0.25 to 0.61. The overall sensitivity and specificity were 18% (95% CI: 14-22) and 97% (95% CI: 97-98), respectively. CONCLUSION: In contrast to adults, the six-point technique assessing anterior, middle, and posterior vertebral height ratios is neither satisfactorily reliable nor sensitive for VF diagnosis in children. Training of the software on paediatric images is required in order to develop a paediatric standard that incorporates not only specific vertebral body height ratios but also the age-related physiological changes in vertebral shape that occur throughout childhood.


Assuntos
Estatura/fisiologia , Densidade Óssea/fisiologia , Diagnóstico por Computador/métodos , Radiografia/métodos , Fraturas da Coluna Vertebral/diagnóstico , Adolescente , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software , Fraturas da Coluna Vertebral/fisiopatologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiopatologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...