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1.
J Archaeol Method Theory ; 30(3): 757-804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600347

RESUMO

Personal ornaments are widely viewed as indicators of social identity and personhood. Ornaments are ubiquitous from the Late Pleistocene to the Holocene, but they are most often found as isolated objects within archaeological assemblages without direct evidence on how they were displayed. This article presents a detailed record of the ornaments found in direct association with an Early Mesolithic buried female infant discovered in 2017 at the site of Arma Veirana (Liguria, Italy). It uses microscopic, 3D, and positional analyses of the ornaments as well as a preliminary perforation experiment to document how they were perforated, used, and what led to their deposit as part of the infant's grave goods. This study provides important information on the use of beads in the Early Mesolithic, in general, as well as the relationship between beads and young subadults, in particular. The results of the study suggest that the beads were worn by members of the infant's community for a considerable period before they were sewn onto a sling, possibly used to keep the infant close to the parents while allowing their mobility, as seen in some modern forager groups. The baby was then likely buried in this sling to avoid reusing the beads that had failed to protect her or simply to create a lasting connection between the deceased infant and her community. Supplementary Information: The online version contains supplementary material available at 10.1007/s10816-022-09573-7.

2.
J Biol Regul Homeost Agents ; 31(4 suppl 1)2017.
Artigo em Inglês | MEDLINE | ID: mdl-29186945

RESUMO

Gamma-glutamyltransferase (GGT) has been recently identified as a bone-resorbing factor. The aim of this study was to investigate the association between plasma GGT fractions levels and bone quality. Plasma GGT fractions were analysed by gel-filtration chromatography. Bone quality was established quantitatively by two micro-CT derived microarchitectural parameters: the BV/TV (mineralised bone volume/total volume), and the SMI (structure model index) that describes the rod-like (low resistant) or plate-like (high-resistant) shape of bone trabeculae. We enrolled 93 patients hospitalised for elective total hip replacement (group Arthrosis, n=46) or for proximal femoral fracture (group Fracture, n=47). Patients within the first quartile of BV/TV (Q1, osteoporotic patients, n=6) showed higher levels of b-GGT fraction [median (min-max): 3.37 (1.42­6.81)] compared to patients with normal bone density (fourth quartile Q4, n=10; 1.40 (0.83­4.36); p=0.0393]. Also, according to SMI, b-GGT value was higher in the subgroup with bone fragility [Q1, n=8: 1.36 (0.43­4.36); Q4, n=8: 5.10 (1.4 ­7.60); p=0.0117]. In conclusion, patients characterised by fragile bone structure showed specifically higher levels of plasma b-GGT activity thus suggesting fractional GGT analysis as a possible biomarker in the diagnosis of osteoporosis.

3.
Oxid Med Cell Longev ; 2017: 9085947, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28852434

RESUMO

Exposure to ionizing radiation during diagnostic procedures increases systemic oxidative stress and predisposes to higher risk of cancer and cardiovascular disease development. Many studies indicated that antioxidants protect against radiation-induced damage and have high efficacy and lack of toxicity in preventing radiation exposure damages. The purpose of this study was to investigate the in vitro protective effect of a new antioxidant mixture, named RiduROS, on oxidative stress generation and DNA double-strand breaks (DSBs) induced by low doses of X-rays in endothelial cells. Human umbilical vein endothelial cells (HUVEC) were treated with RiduROS mixture 24 h before a single exposure to X-rays at an absorbed dose of 0.25 Gy. The production of reactive oxygen species (ROS) was evaluated by fluorescent dye staining and nitric oxide (NO) by the Griess reaction, and DSBs were evaluated as number of γ-H2AX foci. We demonstrated that antioxidant mixture reduced oxidative stress induced by low dose of X-ray irradiation and that RiduROS pretreatment is more effective in protecting against radiation-induced oxidative stress than single antioxidants. Moreover, RiduROS mixture is able to reduce γ-H2AX foci formation after low-dose X-ray exposure. The texted mixture of antioxidants significantly reduced oxidative stress and γ-H2AX foci formation in endothelial cells exposed to low-dose irradiation. These results suggest that RiduROS could have a role as an effective radioprotectant against low-dose damaging effects.


Assuntos
Antioxidantes/farmacologia , Citoproteção , Dano ao DNA , Células Endoteliais da Veia Umbilical Humana/patologia , Células Endoteliais da Veia Umbilical Humana/efeitos da radiação , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Substâncias Protetoras/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Citoproteção/efeitos dos fármacos , Relação Dose-Resposta à Radiação , Histonas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Raios X
4.
Science ; 348(6236): 793-6, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25908660

RESUMO

The Protoaurignacian culture is pivotal to the debate about the timing of the arrival of modern humans in western Europe and the demise of Neandertals. However, which group is responsible for this culture remains uncertain. We investigated dental remains associated with the Protoaurignacian. The lower deciduous incisor from Riparo Bombrini is modern human, based on its morphology. The upper deciduous incisor from Grotta di Fumane contains ancient mitochondrial DNA of a modern human type. These teeth are the oldest human remains in an Aurignacian-related archaeological context, confirming that by 41,000 calendar years before the present, modern humans bearing Protoaurignacian culture spread into southern Europe. Because the last Neandertals date to 41,030 to 39,260 calendar years before the present, we suggest that the Protoaurignacian triggered the demise of Neandertals in this area.


Assuntos
Extinção Biológica , Homem de Neandertal/classificação , Homem de Neandertal/genética , Filogenia , Animais , Arqueologia , Sequência de Bases , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Esmalte Dentário/química , Genoma Mitocondrial/genética , Humanos , Incisivo/anatomia & histologia , Incisivo/química , Dados de Sequência Molecular , Homem de Neandertal/anatomia & histologia , Dente Decíduo/anatomia & histologia , Dente Decíduo/química
5.
Phys Med ; 28(2): 166-73, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21501966

RESUMO

This study investigates the reproducibility of the reconstructed image sharpness, after modifications of the geometry setup, for a variable magnification micro-CT (µCT) scanner. All the measurements were performed on a novel engineered µCT scanner for in vivo imaging of small animals (Xalt), which has been recently built at the Institute of Clinical Physiology of the National Research Council (IFC-CNR, Pisa, Italy), in partnership with the University of Pisa. The Xalt scanner is equipped with an integrated software for on-line geometric recalibration, which will be used throughout the experiments. In order to evaluate the losses of image quality due to modifications of the geometry setup, we have made 22 consecutive acquisitions by changing alternatively the system geometry between two different setups (Large FoV - LF, and High Resolution - HR). For each acquisition, the tomographic images have been reconstructed before and after the on-line geometric recalibration. For each reconstruction, the image sharpness was evaluated using two different figures of merit: (i) the percentage contrast on a small bar pattern of fixed frequency (f = 5.5 lp/mm for the LF setup and f = 10 lp/mm for the HR setup) and (ii) the image entropy. We have found that, due to the small-scale mechanical uncertainty (in the order of the voxel size), a recalibration is necessary for each geometric setup after repositioning of the system's components; the resolution losses due to the lack of recalibration are worse for the HR setup (voxel size = 18.4 µm). The integrated on-line recalibration algorithm of the Xalt scanner allowed to perform the recalibration quickly, by restoring the spatial resolution of the system to the reference resolution obtained after the initial (off-line) calibration.


Assuntos
Engenharia , Processamento de Imagem Assistida por Computador/métodos , Software , Microtomografia por Raio-X/instrumentação , Animais , Calibragem , Fenômenos Mecânicos , Camundongos , Reprodutibilidade dos Testes
6.
Appl Radiat Isot ; 69(12): 1717-20, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21458282

RESUMO

The present study focuses on a micro-PET/CT application to be used for experimental Boron Neutron Capture Therapy (BNCT), which integrates, in the same frame, micro-CT derived anatomy and PET radiotracer distribution. Preliminary results have demonstrated that (18)F-fluoroethyl-tyrosine (FET)/PET allows the identification of the extent of cerebral lesions in F98 tumor bearing rat. Neutron autoradiography and α-spectrometry on axial tissues slices confirmed the tumor localization and extraction, after the administration of fructose-boronophenylalanine (BPA). Therefore, FET-PET approach can be used to assess the transport, the net influx, and the accumulation of FET, as an aromatic amino acid analog of BPA, in experimental animal model. Coregistered micro-CT images allowed the accurate morphological localization of the radiotracer distribution and its potential use for experimental BNCT.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Tirosina/análogos & derivados , Animais , Modelos Animais de Doenças , Ratos , Tirosina/administração & dosagem
7.
Int J Oral Maxillofac Surg ; 40(8): 874-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21470821

RESUMO

Synovial cysts are lesions that usually occur on the wrist, foot and knee. They are rarely involved in the region of the temporomandibular joint (TMJ), with only 10 cases reported from 1978 to 2007. The authors report a case of a synovial cyst of the TMJ in a 45-year-old woman. The patient presented with a right preauricular swelling, 1cm anterior to the tragus. A computed tomography (CT) scan showed a small oval hypodense mass of soft tissue in the right temporomandibular region with no relation to the condyle. Fine needle aspiration reported a synovial cyst of the TMJ. The patient was taken to the operating room and a preauricular approach extending to the temporal region was carried out resulting in surgical excision of the mass. The histological findings were consistent with the diagnosis of a synovial cyst. The long term clinical and radiological follow-up (after 18 months) showed no sign of recurrence. The authors suggest, in accordance with the literature, that a surgical approach should be the treatment of choice in the case of a synovial cyst of the TMJ.


Assuntos
Cisto Sinovial/diagnóstico , Transtornos da Articulação Temporomandibular/diagnóstico , Biópsia por Agulha Fina , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia , Líquido Sinovial , Tomografia Computadorizada por Raios X
8.
Nutr Metab Cardiovasc Dis ; 21(9): 726-32, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21427012

RESUMO

BACKGROUND AND AIMS: Chronic hyperglycaemia aggravates obesity and diabetes mellitus. The use of glucose by body organs depends on several factors. We sought to investigate the role of blood flow, intrinsic tissue glucose clearance and blood glucose levels in regulating tissue glucose uptake under fasting conditions (FCs) and in response to acute hyperglycaemia (AH) in obese and type 2 diabetic rats. METHODS AND RESULTS: Thirty-six Zucker rats were studied by positron emission tomography to quantify perfusion and glucose uptake during FC and after AH in the liver, myocardium, skeletal muscle and subcutaneous adipose tissue. Progressively higher glucose uptake rates were observed from lean to obese (p < 0.05) and to diabetic rats (p < 0.05) in all tissues during both FC and AH. In FC, they were increased of 7-18 times in obese rats and 11-30 times in diabetic rats versus controls. Tissue glucose uptake was increased by over 10-fold during AH in controls; this response was severely blunted in diseased groups. AH tended to stimulate organ perfusion in control rats. Tissue glucose uptake was a function of intrinsic clearance and glycaemia (mass action) in healthy animals, but the latter component was lost in diseased animals. Differences in perfusion did not account for those in glucose uptake. CONCLUSIONS: Each organ participates actively in the regulation of its glucose uptake, which is dependent on intrinsic tissue substrate extraction and extrinsic blood glucose delivery, but not on perfusion, and it is potently stimulated by AH. Obese and diabetic rats had an elevated organ glucose uptake but a blunted response to acute glucose intake.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Glucose/administração & dosagem , Hiperglicemia/fisiopatologia , Obesidade/fisiopatologia , Fluxo Sanguíneo Regional , Doença Aguda , Animais , Velocidade do Fluxo Sanguíneo , Glicemia/análise , Jejum , Glucose/farmacocinética , Fígado/metabolismo , Masculino , Modelos Animais , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Tomografia por Emissão de Pósitrons , Ratos , Ratos Zucker
9.
Phys Med Biol ; 53(14): 3841-61, 2008 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-18583729

RESUMO

In this paper we present a new method for the determination of geometrical misalignments in cone-beam CT scanners, from the analysis of the projection data of a generic object. No a priori knowledge of the object shape and positioning is required. We show that a cost function, which depends on the misalignment parameters, can be defined using the projection data and that such a cost function has a local minimum in correspondence to the actual parameters of the system. Hence, the calibration of the scanner can be carried out by minimizing the cost function using standard optimization techniques. The method is developed for a particular class of 3D object functions, for which the redundancy of the fan beam sinogram in the transaxial midplane can be extended to cone-beam projection data, even at wide cone angles. The method has an approximated validity for objects which do not belong to that class; in that case, a suitable subset of the projection data can be selected in order to compute the cost function. We show by numerical simulations that our method is capable to determine with high accuracy the most critical misalignment parameters of the scanner, i.e., the transversal shift and the skew of the detector. Additionally, the detector slant can be determined. Other parameters such as the detector tilt, the longitudinal shift and the error in the source-detector distance cannot be determined with our method, as the proposed cost function has a very weak dependence on them. However, due to the negligible influence of these latter parameters in the reconstructed image quality, they can be kept fixed at estimated values in both calibration and reconstruction processes without compromising the final result. A trade-off between computational cost and calibration accuracy must be considered when choosing the data subset used for the computation of the cost function. Results on real data of a mouse femur as obtained with a small animal micro-CT are shown as well, proving the capability of the proposed calibration method. In principle, the method can be adapted to other cone-beam imaging modalities (e.g., single photon emission computed tomography).


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Algoritmos , Animais , Calibragem , Fêmur/efeitos da radiação , Processamento de Imagem Assistida por Computador , Camundongos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
J Environ Qual ; 35(4): 1297-308, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16825449

RESUMO

Two swine feeding trials were conducted (initial body weight = 47 +/- 2 and 41 +/- 3 kg for Trials 1 and 2, respectively) to evaluate reduced crude protein (CP) and yucca (Yucca schidigera Roezl ex Ortgies) extract-supplemented diets on NH3 emissions. In Trial 1, nine pigs were offered a corn-soybean meal diet (C, 174 g kg(-1) CP), a Lys-supplemented diet (L, 170 g kg(-1) CP), or a 145 g kg(-1) CP diet supplemented with Lys, Met, Thr, and Trp (LMTT). In Trial 2, nine pigs were fed diet L supplemented with 0, 62.5, or 125 mg of yucca extract per kg diet. Each feeding period consisted of a 4-d dietary adjustment followed by 72 h of continuous NH3 measurement. Urine and fecal samples were collected each period. Feeding the LMTT diet reduced (P < 0.05) average daily gain (ADG) and feed efficiency (G:F) compared to diet L. Fecal N concentration decreased with a reduction in dietary CP, but urinary ammonium increased from pigs fed diet LMTT (2.0 g kg(-1), wet basis) compared to those fed diet C (1.1 g kg(-1)) or L (1.0 g kg(-1)). When pigs were fed reduced CP diets NH3 emission rates decreased (2.46, 2.16, and 1.05 mg min(-1) for diets C, L, and LMTT). Yucca had no effect on feed intake, ADG, or G:F. Ammonium and N concentrations of manure and NH3 emission rates did not differ with yucca content. Caution must be executed to maintain animal performance when strategies are implemented to reduce NH3 emissions.


Assuntos
Amônia/análise , Ração Animal , Fezes/química , Nitrogênio/análise , Suínos/metabolismo , Urina/química , Amônia/metabolismo , Animais , Nitrogênio/metabolismo , Fatores de Tempo
11.
Comput Med Imaging Graph ; 29(8): 587-96, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16290284

RESUMO

At the University of Pisa we are building a PEM prototype, the YAP-PEM camera, consisting of two opposite 6 x 6 x 3 cm3 detector heads of 30 x 30 YAP:Ce finger crystals, 2 x 2 x 30 mm3 each. The camera will be equipped with breast compressors. The acquisition will be stationary. Compared with a whole body PET scanner, a planar Positron Emission Mammography (PEM) camera allows a better, easier and more flexible positioning around the breast in the vicinity of the tumor: this increases the sensitivity and solid angle coverage, and reduces cost. To avoid software rejection of data during the reconstruction, resulting in a reduced sensitivity, we adopted a 3D-EM reconstruction which uses all of the collected Lines Of Response (LORs). This skips the PSF distortion given by data rebinning procedures and/or Fourier methods. The traditional 3D-EM reconstruction requires several times the computation of the LOR-voxel correlation matrix, or probability matrix {p(ij)}; therefore is highly time-consuming. We use the sparse and symmetry properties of the matrix {p(ij)} to perform fast 3D-EM reconstruction. Geometrically, a 3D grid of cubic voxels (FOV) is crossed by several divergent 3D line sets (LORs). The symmetries occur when tracing different LORs produces the same p(ij) value. Parallel LORs of different sets cross the FOV in the same way, and the repetition of p(ij) values depends on the ratio between the tube and voxel sizes. By optimizing this ratio, the occurrence of symmetries is increased. We identify a nucleus of symmetry of LORs: for each set of symmetrical LORs we choose just one LOR to be put in the nucleus, while the others lie outside. All of the possible p(ij) values are obtainable by tracking only the LORs of this nucleus. The coordinates of the voxels of all of the other LORs are given by means of simple translation rules. Before making the reconstruction, we trace the LORs of the nucleus to find the intersecting voxels, whose p(ij) values are computed and stored with their voxel coordinates on a hard disk. Only the non-zero p(ij) are considered and their computation is performed just once. During the reconstruction, the stored values are loaded and are available in the random access memory for all of the operations of normalization, backprojection and projection: these are now performed rapidly, because the application of the translation rules is much faster than the probability computations. We tested the algorithm on Monte Carlo data fully simulating the typical YAP-PEM clinical condition. The adopted algorithm gives an excellent positioning capability for hot spots in the camera FOV. To use all of the possible skew LORs in the FOV avoids the software rejection of collected data. Reconstructed images indicate that a 5mm diameter tumor of 37 kBq/cm3, in an active breast with a 10:1 Tissue to Background ratio (T/B), with a 10 min acquisition, for a head distance of 5 cm, can be detected by the YAP-PEM with a SNR of 8.7+/-1.0. The obtained SNR values depend linearly on the tumor volume. The algorithm allows one to discriminate between two hot sources of 5.0 mm diameter if they do not lie on the same axis. The YAP-PEM is now in the assembly stage.


Assuntos
Desenho de Equipamento , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional , Mamografia/instrumentação , Tomografia por Emissão de Pósitrons , Algoritmos , Feminino , Humanos , Itália , Método de Monte Carlo
12.
DNA Seq ; 11(6): 501-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11696976

RESUMO

The RET proto-oncogene is involved in the development of both kidney and neural crests derived tissues. RET deleterious mutations cause hereditary neuroendocrine tumours and congenital intestinal aganglionosis. Ongoing efforts aimed at elucidating the function of this gene include expression studies in different species and in transgenic mice. As first step in the study of Ret expression in mouse, we obtained the mouse Ret genomic structure. Intron-exon boundaries were determined and sequenced, all introns but the first one were amplified and cloned, and exons positioned in a restriction map. Mouse and human genes comparison indicates a highly conserved genomic organisation, except for exon 21 which is not conserved in mouse. A region extending 386 bp 5' to the first exon was sequenced and compared with its human counterpart. Some features, reported for the human promoter, like the absence of TATA or CAAT boxes and a high GC content, are conserved.


Assuntos
Proteínas de Drosophila , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Receptores Proteína Tirosina Quinases/genética , Animais , Sequência de Bases , DNA Complementar , Humanos , Camundongos , Dados de Sequência Molecular , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret , Homologia de Sequência do Ácido Nucleico , Distribuição Tecidual
14.
Can Oncol Nurs J ; 10(3): 96-100, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11894282

RESUMO

Sixty cancer patients who were undergoing radiation therapy to the pelvis of at least 4,000 cGy in 20 fractions over four weeks were randomized to take or not take Metamucil. Results were analyzed for the presence of radiation-induced diarrhea in two groups: patients taking Metamucil (n = 30) or not taking Metamucil (n = 30). The Murphy Diarrhea Scale was developed to assist in the synthesis of data collected in daily patient-reported diaries. Results were analyzed using ANOVA F-tests. Metamucil significantly decreased the incidence (p = 0.049) and severity (p = 0.030) of diarrhea and showed a strong trend in reducing the use of anti-diarrhea medication (p = 0.062). According to this pilot study, Metamucil was an effective method of controlling radiation-induced diarrhea. Results of this pilot study have implications for clinical practice and nursing research.


Assuntos
Catárticos/uso terapêutico , Diarreia/prevenção & controle , Neoplasias Pélvicas/radioterapia , Psyllium/uso terapêutico , Lesões por Radiação/complicações , Idoso , Análise de Variância , Diarreia/etiologia , Diarreia/enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Lesões por Radiação/enfermagem
15.
Aust N Z J Surg ; 49(2): 228-35, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-313786

RESUMO

One hundred and nineteen patients undergoing cardiac surgery had postoperative myocardial imaging performed with technetium pyrophosphate in order to assess the incidence of perioperative myocardial infarction. Fifty-six patients had only coronary artery bypass graft (CABG) surgery, of whom 13(23%) had a positive scintigram. Thirteen patients had CABG with other cardiac surgery and six (46%) had a positive scintigram. Fifty patients had other cardiac surgery but no CABG, and of these eight (16%) had a positive scintigram. The overall incidence of positive scintigrams was 23%, whereas definite or probable ECG diagnosis of infarction was present in 14 patients (12%). Serum levels of cardiac enzymes were higher in patients with positive scintigrams, but this finding did not consistently reach statistical significance. The use of a left ventricular vent during surgery did not correlate with a positive scintigram, nor did the total time on cardiopulmonary bypass or aortic cross-clamping. Patients having cardiac surgery, including CABG and valve replacement, have a 23% overall incidence of positive scintigrams. This suggests that the incidence of infarction after cardiac surgery is higher than can be recognized from the conventional criteria of ECG and enzyme changes.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Coração/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Ponte de Artéria Coronária , Creatina Quinase/sangue , Eletrocardiografia , Próteses Valvulares Cardíacas , Humanos , Valva Mitral/cirurgia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Complicações Pós-Operatórias , Cintilografia
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