Development of a Strategy to Predict and Detect Falls Using Wearable Sensors.

Falls are a prevalent problem in actual society. Some falls result in injuries and the cost associated with their treatment is high. This is a complex problem that requires several steps in order to be tackled. Firstly, it is crucial to develop strategies that recognize the locomotion mode, indicating the state of the subject in various situations. This article aims to develop a strategy capable of identifying normal gait, the pre-fall condition, and the fall situation, based on a wearable system (IMUs-based). This system was used to collect data from healthy subjects that mimicked falls. The strategy consists, essentially, in the construction and use of classifiers as tools for recognizing the locomotion modes. Two approaches were explored. Associative Skill Memories (ASMs) based classifier and a Convolutional Neural Network (CNN) classifier based on deep learning. Finally, these classifiers were compared, providing for a tool with a good accuracy in recognizing the locomotion modes. Results have shown that the accuracy of the classifiers was quite acceptable. The CNN presented the best results with 92.71% of accuracy considering the pre-fall step different from normal steps, and 100% when not considering.

Effect of different instrumentation techniques on students' performance and outcomes of nonsurgical root canal treatment.

OBJECTIVES: This study compared, retrospectively, the incidence of clinical errors and effects on treatment outcomes, when students were exposed to two different instrumentation techniques: a hybrid rotary technique (HYB), consisting of both hand instrumentation with hand stainless steel and Ni-Ti files plus the use of a rotary system (Vortex Blue, Dentsply Sirona), versus a full reciprocation instrumentation technique (WaveOne Gold [WOG], Dentsply Sirona). METHODS: A total of 368 endodontic cases (n = 184) in anterior and premolar teeth, completed by dental students at the University of Michigan School of Dentistry from 2013 to 2022, were used for the study. The groups were evaluated by two calibrated clinicians, observing the incidence of clinical errors: file separations, over-instrumentation, ledges and transportations. Treatment outcomes were also observed. Data were analyzed statistically by Fisher's exact test and Mann-Whitney U test (p < 0.05). RESULTS: No significant difference in file separations, ledges, and transportation was observed between the two groups. However, the WOG Group experienced significantly more over-instrumentation than HYB group, although this did not significantly affect tooth survival or periapical index (PAI). Cases with PAI scores of 5 were found to have significantly less tooth survival compared to the other PAI scores. CONCLUSIONS: It can be concluded that both techniques in our study are well suited to advancing the endodontic dental education of students and novice operators, anticipating relatively successful outcomes of tooth survival, as long as the cases selected are less severe in progression preoperatively.

A multi-camera and multimodal dataset for posture and gait analysis.

Monitoring gait and posture while using assisting robotic devices is relevant to attain effective assistance and assess the user's progression throughout time. This work presents a multi-camera, multimodal, and detailed dataset involving 14 healthy participants walking with a wheeled robotic walker equipped with a pair of affordable cameras. Depth data were acquired at 30 fps and synchronized with inertial data from Xsens MTw Awinda sensors and kinematic data from the segments of the Xsens biomechanical model, acquired at 60 Hz. Participants walked with the robotic walker at 3 different gait speeds, across 3 different walking scenarios/paths at 3 different locations. In total, this dataset provides approximately 92 minutes of total recording time, which corresponds to nearly 166.000 samples of synchronized data. This dataset may contribute to the scientific research by allowing the development and evaluation of: (i) vision-based pose estimation algorithms, exploring classic or deep learning approaches; (ii) human detection and tracking algorithms; (iii) movement forecasting; and (iv) biomechanical analysis of gait/posture when using a rehabilitation device.

From raw measurements to human pose - a dataset with low-cost and high-end inertial-magnetic sensor data.

Wearable technology is expanding for motion monitoring. However, open challenges still limit its widespread use, especially in low-cost systems. Most solutions are either expensive commercial products or lower performance ad-hoc systems. Moreover, few datasets are available for the development of complete and general solutions. This work presents 2 datasets, with low-cost and high-end Magnetic, Angular Rate, and Gravity(MARG) sensor data. Provides data for the complete inertial pose pipeline analysis, starting from raw data, sensor-to-segment calibration, multi-sensor fusion, skeleton-kinematics, to complete Human pose. Contains data from 21 and 10 participants, respectively, performing 6 types of sequences, presenting high variability and complex dynamics with almost complete range-of-motion. Amounts to 3.5 M samples, synchronized with a ground-truth inertial motion capture system. Presents a method to evaluate data quality. This database may contribute to develop novel algorithms for each pipeline's processing steps, with applications in inertial pose estimation algorithms, human movement forecasting, and motion assessment in industrial or rehabilitation settings. All data and code to process and analyze the complete pipeline is freely available.

Brain Abscess: A Rare Clinical Case with Oral Etiology.

Brain abscess is a very rare condition but has a significant mortality rate. The three main routes of inoculation are trauma, contiguous focus, and the hematogenous route. The odontogenic focus is infrequent and is usually a diagnosis of exclusion. This paper presents a brain abscess case proven to be of dental origin, caused by Actinomyces meyeri and Fusobacterium nucleatum. This case highlights the risk underlying untreated dental disease and why oral infectious foci removal and good oral health are essential in primary care.

The interaction of La(3+) complexes of DOTA/DTPA glycoconjugates with the RCA(120) lectin: a saturation transfer difference NMR spectroscopic study.

The study of ligand-receptor interactions using high-resolution NMR techniques, namely the saturation transfer difference (STD), is presented for the recognition process between La(III) complexes of 1,4,7,10-tetrakis(carboxymethyl)-1,4,7,10-tetraazacyclododecane monoamide and diethylenetriaminepentaacetic acid bisamide glycoconjugates and the galactose-specific lectin Ricinus communis agglutinin (RCA(120)). This new class of Gd(III)-based potential targeted MRI contrast agents (CAs), bearing one or two terminal sugar (galactosyl or lactosyl) moieties, has been designed for in vivo binding to the asialoglycoprotein receptor, which is specifically expressed at the surface of liver hepatocytes, with the aim of leading to a new possible diagnosis of liver diseases. The in vitro affinity constants for the affinity of the divalent La(III)-glycoconjugate complexes for RCA(120), used as a simple, water-soluble receptor model, were higher than those of the monovalent analogues. The combination of the experimental data obtained from the STD NMR experiments with molecular modelling protocols (Autodock 4.1) allowed us to predict the mode of binding of monovalent and divalent forms of these CAs to the galactose 1α binding sites of RCA(120). The atomic details of the molecular interactions allowed us to corroborate and supported the interaction of both sugar moieties and the linkers with the surface of the protein and, thus, their contribution to the observed interaction stabilities.

Gallium labeled NOTA-based conjugates for peptide receptor-mediated medical imaging.

We report a straightforward and efficient synthetic strategy for the synthesis of three model glycine-arginine-glycine-aspartic acid-glycine (GRGDG) conjugates based on derivatives of NOTA and of their Ga(III) complexes targeted to the integrin α(ν)ß(3) receptor. (71)Ga NMR spectroscopy showed that the Ga(III)-labeled conjugates are highly stable in aqueous solution. The (67)Ga-labeled conjugates proved to have high kinetic stability and showed a weak but specific binding to the receptors in a U87MG-glioblastoma cell line.

Open Proximal Contact with Implant-Supported Fixed Prostheses Compared with Tooth-Supported Fixed Prostheses: A Systematic Review and Meta-analysis.

PURPOSE: To investigate the odds of developing open proximal contact (OPC) between implant-supported fixed prostheses and adjacent teeth compared with that between tooth-supported fixed prostheses and adjacent teeth. MATERIALS AND METHODS: A search was conducted in the Ovid MEDLINE, Embase, and Web of Science databases for clinical studies on OPC developed with implant-supported prostheses or tooth-supported prostheses. A meta-analysis was performed using statistical software to estimate the odds of developing OPC with implant-supported prostheses compared with tooth-supported prostheses, with a 95% confidence interval (CI). The statistical significance was defined as P < .05. RESULTS: The odds ratio (OR) of developing OPC with implant-supported prostheses was 2.46 compared with tooth-supported prostheses (95% CI [1.21 to 5.01]; P = .013]. However, the data were highly heterogenous (τ2 = 0.40, I2 = 95.67%). The total estimates of developing OPC were 41% (95% CI [30% to 54%]) with implant-supported prostheses and 22% (95% CI [18% to 26%]) with tooth-supported prostheses. OPC was more prevalent at the mesial side than at the distal side of implant-supported prostheses (OR = 2.38, 95% CI [0.94 to 6]; P = .066), whereas OPC was more prevalent at the distal side than at the mesial side of tooth-supported prostheses (OR = 1.94, 95% CI [1.09 to 3.45]; P = .024). There was no statistically significant difference in developing OPC with covariates of sex, age, arch, splinting of implants or adjacent teeth, region, and vitality of adjacent teeth, retention type, opposing dentition, occlusal force, parafunctional activities, and follow-up time. OPC was found to increase 9% per year with implant-supported prostheses (OR = 1.09). The estimate of interproximal gap next to implant-supported prostheses was 245.8 µm (95% CI [86.4 to 405.3 µm]). CONCLUSION: Within the limitations of this systematic review and meta-analysis, the odds of developing OPC were significantly higher with implant-supported prostheses than with tooth-supported prostheses. However, the data were highly heterogenous, and thus, a well-designed randomized clinical study needs to be conducted to validate the results of this systematic review.

Gallium(III) chelates of mixed phosphonate-carboxylate triazamacrocyclic ligands relevant to nuclear medicine: Structural, stability and in vivo studies.

Three triaza macrocyclic ligands, H6NOTP (1,4,7-triazacyclononane-N,N',N″-trimethylene phosphonic acid), H4NO2AP (1,4,7-triazacyclononane-N-methylenephosphonic acid-N',N″-dimethylenecarboxylic acid), and H5NOA2P (1,4,7-triazacyclononane-N,N'-bis(methylenephosphonic acid)-N″-methylene carboxylic acid), and their gallium(III) chelates were studied in view of their potential interest as scintigraphic and PET (Positron Emission Tomography) imaging agents. A 1H, 31P and 71Ga multinuclear NMR study gave an insight on the structure, internal dynamics and stability of the chelates in aqueous solution. In particular, the analysis of 71Ga NMR spectra gave information on the symmetry of the Ga3+ coordination sphere and the stability of the chelates towards hydrolysis. The 31P NMR spectra afforded information on the protonation of the non-coordinated oxygen atoms from the pendant phosphonate groups and on the number of species in solution. The 1H NMR spectra allowed the analysis of the structure and the number of species in solution. 31P and 1H NMR titrations combined with potentiometry afforded the measurement of the protonation constants (log KHi) and the microscopic protonation scheme of the triaza macrocyclic ligands. The remarkably high thermodynamic stability constant (log KGaL=34.44 (0.04) and stepwise protonation constants of Ga(NOA2P)2- were determined by potentiometry and 69Ga and 31P NMR titrations. Biodistribution and gamma imaging studies have been performed on Wistar rats using the radiolabeled 67Ga(NO2AP)- and 67Ga(NOA2P)2-chelates, having both demonstrated to have renal excretion. The correlation of the molecular properties of the chelates with their pharmacokinetic properties has been analysed.

Alkaline Earth Metal and Lanthanide(III) Complexes of Ligands Based upon 1,4,7,10-Tetraazacyclododecane-1,7-bis(acetic acid).

The macrocyclic ligand DO2A (1,4,7,10-tetraazacyclododecane-1,7-bis(acetic acid)) was prepared and used as a building block for four new macrocyclic ligands having mixed side-chain chelating groups. These ligands and their complexes with Mg(II), Ca(II), and Ln(III) were studied extensively by potentiometry, high-resolution NMR, and water proton relaxivity measurements. The protonation constants of all compounds compared well with those of other cyclen-based macrocyclic ligands. All Ca(II) complexes were found to be more stable than the corresponding Mg(II) complexes. Trends for the stabilities of the Ln(III) complexes are discussed and compared with literature data, incorporating the effects of water coordination numbers, Ln(III) contraction, and the nature of the side chains and the steric hindrance between them. (1)H NMR titrations of DO2A revealed that the first and second protonations take place preferentially at the secondary ring nitrogens, while the third and fourth involved protonation of the acetates. (17)O NMR shifts showed that the DyDO2A(+) complex had two inner-sphere water molecules. Water proton spin-lattice relaxation rates for the GdDO2A(+) complex were also consistent with water exchange between bulk water and two inner-sphere Gd(III) coordination positions. Upon formation of the diamagnetic complexes of DO2A (Ca(II), Mg(II), La(III), and Lu(III)), all of the macrocyclic ring protons became nonequivalent due to slow conformational rearrangements, while the signals for the acetate CH(2) protons remained a singlet.

In vivo and in vitro (27)Al NMR studies of aluminum(III) chelates of triazacyclononane polycarboxylate ligands.

The metallic radioisotope of a known radiopharmaceutical chelate, (67)Ga(NOTA) (NOTA=1,4,7-triazacyclonane-1,4,7-triacetic acid), used for tumor detection, was substituted by the chemically similar but non radioactive aluminum ion. Our aim was to detect and evaluate the in vivo behavior of the chelate. For this purpose, Al(NOTA) and the related chelate Al(NODASA) (NODASA=1,4,7-triazacyclononane-1-succinic acid-4,7-diacetic acid) were studied using in vitro and in vivo (27)Al NMR spectroscopy in rats. Both chelates showed high stability towards acid catalyzed dissociation and their (27)Al NMR resonances are characteristic of highly symmetrical species, with chemical shifts within the range for octahedral or pseudo-octahedral geometries. The thermodynamic stability constant of the novel chelate Al(NODASA) was estimated using (27)Al NMR. The value obtained suggested that the chelate does not undergo in vivo demetalation by transferrin. The in vivo spectroscopic studies and the analysis of blood and urine samples for Al(III) concentrations indicated that the chelates remain intact under physiological conditions and that they are mainly eliminated from the body through the kidneys.

Ga[NO2A-N-(α-amino)propionate] chelates: synthesis and evaluation as potential tracers for 68Ga PET.

The availability of commercial (68)Ge/(68)Ga cyclotron-independent (68)Ga(3+) generators is making Positron Emission Tomography (PET) accessible to most hospitals, which is generating a surge of interest in the design and synthesis of bi-functional chelators for Ga(3+). In this work we introduce the NO2A-N-(α-amino)propionic acid family of chelators based on the triazacyclononane scaffold. Complexation of the parent NO2A-N-(α-amino)propionic acid chelator and of a low molecular weight (model) amide conjugate with Ga(3+) was studied by (1)H and (71)Ga NMR. The Ga(3+) chelate of the amide conjugate shows pH-independent N3O3 coordination in the pH range 3-10 involving the carboxylate group of the pendant propionate arm in a 6 member chelate. For the Ga[NO2A-N-(α-amino)propionate] chelate, a reversible pH-triggered switch from Ga(3+) coordination to the carboxylate group to coordination to the amine group of the propionate arm was observed upon pH increase/decrease in the pH range 4-6. This phenomenon can conceivably constitute the basis of a physiological pH sensor. Both complexes are stable in the physiological range. The [(67)Ga][NO2A-N-(α-benzoylamido)propionate] chelate was found to be stable in human serum. Biodistribution studies of the (67)Ga(3+)-labeled pyrene butyric acid conjugate NO2A-N-(α-pyrenebutanamido)propionic acid revealed that, despite its high lipophilicity and concentration-dependent aggregation properties, the chelate follows mainly renal elimination with very low liver/spleen accumulation and no activity deposition in bones after 24 hours. Facile synthesis of amide conjugates of the NO2A-N-(α-amino)propionic acid chelator, serum stability of the Ga(3+) chelates and fast renal elimination warrant further evaluation of this novel class of chelators for PET applications.

Thermodynamic stability and relaxation studies of small, triaza-macrocyclic Mn(II) chelates.

Due to its favorable relaxometric properties, Mn(2+) is an appealing metal ion for magnetic resonance imaging (MRI) contrast agents. This paper reports the synthesis and characterization of three new triazadicarboxylate-type ligands and their Mn(2+) chelates (NODAHep, 1,4,7-triazacyclononane-1,4-diacetate-7-heptanil; NODABA, 1,4,7-triazacyclononane-1,4-diacetate-7-benzoic acid; and NODAHA, 1,4,7-triazacyclononane-1,4-diacetate-7-hexanoic acid). The protonation constants of the ligands and the stability constants of the chelates formed with Mn(2+) and the endogenous Zn(2+) ion have been determined by potentiometry. In overall, the thermodynamic stability of the chelates is lower than that of the corresponding NOTA analogues (NOTA = 1,4,7-triazacyclononane-1,4,7-triacetate), consistent with the decreased number of coordinating carboxylate groups. Variable temperature (1)H NMRD and (17)O NMR measurements have been performed on the paramagnetic chelates to provide information on the water exchange rates and the rotational dynamics. The values of the (17)O chemical shifts are consistent with the presence of one water molecule in the first coordination sphere of Mn(2+). The three complexes are in the slow to intermediate regime for the water exchange rate, and they all display relatively high rotational correlation times, which explain the relaxivity values between 4.7 and 5.8 mM(-1) s(-1) (20 MHz and 298 K). These relaxivities are higher than expected for Mn(2+) chelates of such size and comparable to those of small monohydrated Gd(3+) complexes. The amphiphilic [Mn(NODAHep)] forms micelles above 22 mM (its critical micellar concentration was determined by relaxometry and fluorescence), and interacts with HSA via its alkylic carbon chain providing a 60% relaxivity increase at 20 MHz due to a longer tumbling time.

COMPARISON BETWEEN MAGNETIC RESONANCE IMAGING AND ULTRASONOGRAPHY AS THE BEST EXAMINATION TO MEASURE MALIGNANT BREAST TUMORS IN SURGICAL PLANNING / Comparação entre ressonância magnética e ultrassonografia como melhor exame para mensurar tumores malignos da mama no planejamento cirúrgico

Objective: To evaluate which examination, ultrasonography or magnetic resonance imaging, is more accurate in the measurement of malignant breast tumors in the pre-surgical evaluation, according to hormonal status. Method: This is a descriptive, crosssectional study in which we compared the largest tumor-size visualized by magnetic resonance imaging and ultrasonography before excision with the largest size visualized in the anatomopathological report. The sample was divided according to hormonal status: premenopausal women, postmenopausal women who have already had hormone-replacement therapy, and postmenopausal women who have never done hormone-replacement therapy. We evaluated which of the exams had a greater correlation with the size measured by the anatomopathological report using the Pearson correlation coefficient. Results: All the 39 patients had invasive-ductal carcinoma. When the total sample was analyzed (n=39), it was observed that the correlation between the ultrasonography and the anatomopathological report (r=0.73; p<0.001) was higher than the correlation between the magnetic resonance imaging and the anatomopathological report (r=0.57; p<0.001). In the premenopausal subgroup, the correlation between the ultrasonography and the anatomopathological report (r=0.46; p=0.05) was lower than the correlation between the magnetic resonance imaging and the anatomopathological report, (r=0.56; p=0.01). In the postmenopausal subgroup, Pearson's correlation shows that ultrasonography is better at assessing tumor size than magnetic resonance imaging, regardless of hormonereplacement therapy. Conclusion: Ultrasonography is satisfactory for pre-surgical staging in invasive-ductal carcinoma, but, when available, magnetic resonance imaging may be a better indication in premenopausal patients

Objetivo: Avaliar qual exame, ultrassonografia ou ressonância magnética, é mais preciso para dimensionar tumores malignos da mama na avaliação pré-cirúrgica, de acordo com o status hormonal. Metodologia: Trata-se de um estudo descritivo e transversal, no qual comparamos o maior diâmetro do tumor visualizado pela ressonância magnética e pela ultrassonografia antes da excisão com o maior tamanho visualizado no exame anatomopatológico da peça cirúrgica. A amostra foi dividida conforme o estado hormonal: mulheres pré-menopáusicas; pós-menopáusicas que já tiveram terapia de reposição hormonal; e pós-menopáusicas sem terapia de reposição hormonal. Avaliamos qual dos exames teve maior correlação com o tamanho medido pelo laudo anatomopatológico usando o coeficiente de correlação de Pearson. Resultados: Todas as 39 pacientes apresentavam carcinoma ductal invasivo. Na amostra total (n=39), a correlação entre ultrassonografia e exame anatomopatológico (r=0,73; p<0,001) foi maior que a correlação entre ressonância magnética e exame anatomopatológico (r=0,57; p<0,001). No subgrupo pré-menopausa, a correlação entre ultrassonografia e exame anatomopatológico (r=0,46; p=0,05) foi inferior à correlação entre ressonância magnética e exame anatomopatológico (r=0,56; p=0,01). Nas pós-menopáusicas, a correlação de Pearson mostra que a ultrassonografia é melhor para avaliar o tamanho do tumor do que a ressonância magnética, independentemente da utilização de terapia de reposição hormonal. Conclusão: A ultrassonografia é satisfatória para mensuração pré-operatória do carcinoma ductal invasivo, mas quando disponível, a ressonância magnética pode estar bem indicada em pacientes pré-menopáusicas.

Ga(III) chelates of amphiphilic DOTA-based ligands: synthetic route and in vitro and in vivo studies.

In this work, we report on a synthetic strategy using amphiphilic DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-based chelators bearing a variable-sized α-alkyl chain at one of the pendant acetate arms (from 6 to 14 carbon atoms), compatible with their covalent coupling to amine-bearing biomolecules. The amphiphilic behavior of the micelles-forming Ga(III) chelates (critical micellar concentration), their stability in blood serum and their lipophilicity (logP) were investigated. Biodistribution studies with the (67)Ga-labeled chelates were performed in Wistar rats, which showed a predominant liver uptake with almost no traces of the radiochelates in the body after 24 h.

Triaza-based amphiphilic chelators: synthetic route, in vitro characterization and in vivo studies of their Ga(III) and Al(III) chelates.

Radiogallium chelates are important for diagnostic imaging in nuclear medicine (PET (positron emission tomography) and gamma-scintigraphy). Micelles are adequate colloidal vehicles for the delivery of therapeutic and diagnostic agents to organs and tissues. In this paper we describe the synthesis and in vitro and in vivo studies of a series of micelles-forming Ga(III) chelates targeted for the liver. The amphiphilic ligands are based on NOTA (NOTA=1,4,7-triazacyclonoane-N,N'N''-triacetic acid) and bear a alpha-alkyl chain in one of the pendant acetate arms (the size of the chain changes from four to fourteen carbon atoms). A multinuclear NMR study ((1)H, (13)C, (27)Al and (71)Ga) gave some insights into the structure and dynamics of the metal chelates in solution, consistent with their rigidity and octahedral or pseudo-octahedral geometry. The critical micellar concentration of the chelates was determined using a fluorescence method and (27)Al NMR spectroscopy (Al(III) was used as a surrogate of Ga(III)), both showing similar results and suggesting that the chelates of NOTAC6 form pre-micellar aggregates. The logP (octanol-water) determination showed enhancement of the lipophilic character of the Ga(III) chelates with the increase of the number of carbons in the alpha-alkyl chain. Biodistribution and gamma-scintigraphic studies of the (67)Ga(III) labeled chelates were performed on Wistar rats, showing higher liver uptake for [(67)Ga](NOTAC8) in comparison to [(67)Ga](NOTAC6), consistent with a longer alpha-alkyl chain and a higher lipophilicity. After 24h both chelates were completely cleared off from the tissues and organs with no deposition in the bones and liver/spleen. [(67)Ga](NOTAC8) showed high kinetic stability in blood serum.

Lanthanide chelates of (bis)-hydroxymethyl-substituted DTTA with potential application as contrast agents in magnetic resonance imaging.

A novel bis-hydroxymethyl-substituted DTTA chelator N'-Bz-C(4,4')-(CH(2)OH)(2)-DTTA () and its DTPA analogue C(4,4')-(CH(2)OH)(2)-DTPA () were synthesized and characterized. A variable-temperature (1)H NMR spectroscopy study of the solution dynamics of their diamagnetic (La) and paramagnetic (Sm, Eu) Ln(3+) complexes showed them to be rigid when compared with analogous Ln(3+)-DTTA and Ln(3+)-DTPA complexes, as a result of their C(4,4')-(CH(2)OH)(2) ligand backbone substitution. The parameters that govern the water (1)H relaxivity of the [Gd()(H(2)O)(2)](-) and [Gd()(H(2)O)](2-) complexes were obtained by (17)O and (1)H NMR relaxometry. While the relaxometric behaviour of the [Gd()(H(2)O)](2-) complex is very similar to the parent [Gd(DTPA)(H(2)O)](2-) system, the [Gd()(H(2)O)(2)](-) complex displays higher relaxivity, due to the presence of two inner sphere water molecules and an accelerated, near optimal water exchange rate. The [Gd()(H(2)O)(2)](-) complex interacts weakly with human serum albumin (HSA), and its fully bound relaxivity is limited by slow water exchange, as monitored by (1)H NMR relaxometry. This complex interacts weakly with phosphate, but does not form ternary complexes with bidentate bicarbonate and l-lactate anions, indicating that the two inner-sphere water molecules of the [Gd()(H(2)O)(2)](-) complex are not located in adjacent positions in the coordination sphere of the Gd(3+) ion. The transmetallation reaction rate of [Gd()(H(2)O)(2)](-) with Zn(2+) in phosphate buffer solution (pH 7.0) was measured to be similar to that of the backbone unsubstituted [Gd(DTTA-Me)(H(2)O)(2)](-), but twice faster than for [Gd(DTPA-BMA)(H(2)O)]. The in vivo biodistribution studies of the (153)Sm(3+)-labelled ligand () in Wistar rats reveal slow blood elimination and short term fixation in various organs, indicating some dissociation. The bis-hydroxymethyl-substituted DTTA skeleton can be seen as a new lead for the synthesis of high relaxivity contrast agents, although its low thermodynamic and kinetic stability will limit its use to in vitro and animal studies.

Preconceito contra homossexuais no contexto do futebol / Prejuicio contra homosexuales en el contexto de fútbol / Prejudice against homosexuals in the soccer context

Este estudo analisa a relação entre as crenças sobre a natureza da homossexualidade e a homofobia no futebol. Participaram 184 jogadores de futebol, a maioria do sexo masculino (74%), com idade média de 24,5 anos. Os participantes responderam as escalas de crenças sobre a homossexualidade, preconceito e expressão emocional. Os resultados demonstram que os participantes do sexo feminino apresentam-se com menos atitudes preconceituosas do que os do sexo masculino e os mais novos exprimem maior homofobia do que os participantes mais velhos. Relativamente às crenças, os esportistas com maior adesão às crenças de natureza ético-moral da homossexualidade exprimem mais atitudes homofóbicas. Já os esportistas com maior adesão à crença sobre a natureza da homossexualidade baseada em justificativas culturais são aqueles com atitudes menos homofóbicas. Os resultados são discutidos à luz do papel desempenhado pelas crenças sobre a natureza da homossexualidade enquanto princípios organizadores do preconceito homofóbico...

Este estudio examina la relación entre las creencias sobre la naturaleza de la homosexualidad y la homofobia en el fútbol. Participaron 184 jugadores de fútbol, la mayoría hombres (74%) con una edad media de 24,5 años, que completaron escalas de creencias sobre la homosexualidad, el prejuicio y la expresión emocional. Los resultados muestran que las mujeres presentan menos actitudes prejuiciosas que los hombres y los más jovenes presentan más homofobia que los de mayor edad. Los atletas con mayor adherencia a las creencias éticas y morales de la naturaleza de la homosexualidad expresaron actitudes más homofóbicas. Ya los atletas con mayor adhesión a la creencia sobre la naturaleza de la homosexualidad basada en justificaciones culturales son los que tienen menos actitudes homofóbicas. Los resultados se discuten a la luz del papel de las creencias acerca de la naturaleza de la homosexualidad como principios organizativos de los prejuicios homofóbicos...

This study examines the relationship between beliefs about the nature of homosexuality and homophobia in the soccer context. Participated 184 Portuguese soccer players, most of them were male (74%) with a mean age of 24.5 years. Participants responded to scales of beliefs about homosexuality, prejudice and emotional expression. The results show that female participants expressed less prejudiced attitudes than male ones, and that younger expressed greater homophobia than older participants. Regarding beliefs, participants who more adhered to ethical-moral beliefs about the nature of homosexuality expressed more homophobic attitudes, while participants who more strongly endorsed belief on the cultural nature of homosexuality expressed less homophobic attitudes. The results are discussed in light of the role played by the beliefs about the nature of homosexuality as organising principles of homophobic prejudice...

68Ga-PET: a powerful generator-based alternative to cyclotron-based PET radiopharmaceuticals.

PET (positron emission tomography) is a powerful diagnostic and imaging technique which requires short-lived positron emitting isotopes. The most commonly used are accelerator-produced (11)C and (18)F. An alternative is the use of metallic positron emitters. Among them (68)Ga deserves special attention because of its availability from long-lived (68)Ge/(68)Ga generator systems which render (68)Ga radiopharmacy independent of an onsite cyclotron. The coordination chemistry of Ga(3+) is dominated by its hard acid character. A variety of mono- and bifunctional chelators have been developed which allow the formation of stable (68)Ga(3+)complexes and convenient coupling to biomolecules. (68)Ga coupling to small biomolecules is potentially an alternative to (18)F- and (11)C-based radiopharmacy. In particular, peptides targeting G-protein coupled receptors overexpressed on human tumour cells have shown preclinically and clinically high and specific tumour uptake. Kit-formulated precursors along with the generator may be provided, similar to the (99)Mo/(99m)Tc-based radiopharmacy, still the mainstay of nuclear medicine.