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2.
Nat Commun ; 13(1): 5052, 2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36030293

RESUMO

UV resonance Raman spectroscopy of size-selected linear sp-carbon chains unveils vibrational overtones and combinations up to the fifth order. Thanks to the tunability of the synchrotron source, we excited each H-terminated polyyne (HCnH with n = 8,10,12) to the maxima of its vibronic absorption spectrum allowing us to precisely determine the electronic and vibrational structure of the ground and excited states for the main observed vibrational mode. Selected transitions are shown to enhance specific overtone orders in the Raman spectrum in a specific way that can be explained by a simple analytical model based on Albrecht's theory of resonance Raman scattering. The determined Huang-Rhys factors indicate a strong and size-dependent electron-phonon coupling increasing with the sp-carbon chain length.

3.
Phys Rev Lett ; 126(3): 037002, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33543973

RESUMO

We report a comprehensive Cu L_{3}-edge resonant x-ray scattering (RXS) study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa_{2}Cu_{3}O_{6.67} under uniaxial compression up to 1% along the two inequivalent Cu─O─Cu bond directions (a and b) in the CuO_{2} planes. We confirm the strong in-plane anisotropy of the 2D charge correlations and observe their symmetric response to pressure: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic RXS measurements show that the 3D charge order resides exclusively in the CuO_{2} planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.

4.
Science ; 362(6418): 1040-1044, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30498124

RESUMO

Cuprates exhibit antiferromagnetic, charge density wave (CDW), and high-temperature superconducting ground states that can be tuned by means of doping and external magnetic fields. However, disorder generated by these tuning methods complicates the interpretation of such experiments. Here, we report a high-resolution inelastic x-ray scattering study of the high-temperature superconductor YBa2Cu3O6.67 under uniaxial stress, and we show that a three-dimensional long-range-ordered CDW state can be induced through pressure along the a axis, in the absence of magnetic fields. A pronounced softening of an optical phonon mode is associated with the CDW transition. The amplitude of the CDW is suppressed below the superconducting transition temperature, indicating competition with superconductivity. The results provide insights into the normal-state properties of cuprates and illustrate the potential of uniaxial-pressure control of competing orders in quantum materials.

5.
Vet J ; 229: 31-36, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183571

RESUMO

The aim of this study was to evaluate echocardiographic and electrocardiographic parameters during the normal canine postpartum period. Twenty clinically healthy pregnant bitches of toy breeds (11 Miniature poodles, five Yorkshire terriers, two Maltese terriers and two Bichons Frises) were evaluated on days -3, 3, 10, 17, 24, 38, 52 and 80 relative to parturition (day 0). During the first postpartum week, the width of the interventricular septum in systole, the shortening fraction and the left atrium size decreased, while the left ventricle internal diameter in systole and end systolic stress increased. There were progressive decreases in the velocity of circumferential fibre shortening, stroke volume, cardiac output, and mitral E and A wave values. Systolic blood pressure increased markedly during the first postpartum week to gradually increase thereafter. Heart rate and corrected QT interval progressively decreased, while P wave amplitude increased. QRS complex amplitude decreased in the second week after parturition and then increased during the following weeks. In conclusion, there were changes in systolic function and some structural adaptive changes in the bitch during the first 80days postpartum. In addition, maternal heart rate and corrected QT interval decreased, while P wave and QRS amplitudes increased.


Assuntos
Cães/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Animais , Cruzamento , Débito Cardíaco , Doenças do Cão/diagnóstico por imagem , Ecocardiografia/veterinária , Eletrocardiografia/veterinária , Feminino , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/veterinária , Período Pós-Parto , Gravidez , Transtornos Puerperais/diagnóstico por imagem , Transtornos Puerperais/veterinária , Valores de Referência , Volume Sistólico
6.
Theriogenology ; 85(7): 1258-61, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26810829

RESUMO

Doppler ultrasound is a useful diagnosis tool to evaluate uterine blood flow in different canine reproductive states. The aim of this study was to describe and compare uterine blood flow in bitches suffering from cystic endometrial hyperplasia (CEH) and CEH-pyometra complex (CEH-P). Ninety diestrous bitches were clinically, hematologically, and ultrasonographically classified into four groups: (1) clinical signs, leukocytosis, CEH, and uterine luminal contents (CEH-P, n = 31); (2) asymptomatic bitches with CEH and uterine contents (CEH-C, n = 15); (3) asymptomatic bitches with CEH without uterine contents (CEH, n = 16); and (4) normal diestrous bitches (ND, n = 28). The widest cross-sectional diameter and uterine wall thickness (W) of uterine horns were measured using two-dimensional ultrasound. Peak systolic velocity and end diastolic velocity of uterine arteries were measured by Doppler ultrasound in all the bitches. Peak systolic velocity and end diastolic velocity were higher in CEH-P than in CEH-C, CEH, and ND (P < 0.01); although both parameters did not show differences among the latter three groups (P > 0.1). Conversely, resistance index (RI) reported lower values in CEH-P than that in the other three groups (P < 0.01), being ND higher (P < 0.01) than both CEH-C and CEH which did not differ between themselves (P > 0.1). When all the bitches were considered, correlation between RI and cross-sectional diameter was r = -0.69 (P < 0.01) and between RI and uterine wall thickness was r = -0.02 (P > 0.1). It is concluded that the uterine artery blood flow velocity of bitches suffering from pyometra was higher, not only from normal bitches, but also from females with endometrial hyperplasia. Furthermore, endometrial hyperplasia, accompanied or not by luminal contents, had a higher blood flow velocity than normal uterus. Hemodynamic parameters appear as useful markers to differentiate uterine pathologic conditions.


Assuntos
Doenças do Cão/patologia , Hiperplasia Endometrial/veterinária , Piometra/veterinária , Útero/irrigação sanguínea , Animais , Cães , Hiperplasia Endometrial/patologia , Feminino , Piometra/patologia
7.
J Mater Chem B ; 4(40): 6516-6523, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263696

RESUMO

We present a combined spectroscopic and computational approach aimed to elucidate the mechanism of formation and activity of etoposide nanoaggregates upon release from dextran-etoposide conjugates. Etoposide is an anticancer drug that inhibits cell growth by blocking Topoisomerase II, the key enzyme involved in re-ligation of the DNA chains during the replication process. In silico and spectroscopic analysis indicate that released etoposide nanoaggregates have a different structure, stability, and bioactivity, which depend on the pH experienced during the release. Molecular dynamics simulation and in silico docking of etoposide dimers suggest that the aggregation phenomena inhibit etoposide bioactivity, yet without drastically preventing Topoisomerase II binding. We correlated the diminished cytotoxic activity exerted by dextran-etoposide conjugates on the A549 lung cancer cells, compared to the free drug, to the formation and stability of drug nanoaggregates.

8.
J Hosp Infect ; 88(4): 183-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25447199

RESUMO

The development of new antimicrobial therapeutic tools addresses the emergence of multidrug-resistant micro-organisms or clones and the need for more effective antimicrobial strategies. Overcoming the hurdles in providing early diagnosis and intervention on hard-to-reach and/or resting bacteria (i.e. biofilm-embedded cells) represents a challenging task. In this review, we identify a set of organic, inorganic, and hybrid materials that might be used for prevention and control of healthcare-associated infections. We report the current knowledge on nano- and microparticle-based antimicrobial agents and describe the possible mode of their action.


Assuntos
Anti-Infecciosos/farmacologia , Nanomedicina , Anti-Infecciosos/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Polímeros/química , Prata/química , Prata/farmacologia
9.
Anim Reprod Sci ; 146(1-2): 63-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24602508

RESUMO

The aim of this study was to describe Doppler parameters of uterine, umbilical, fetal abdominal aorta, fetal renal and fetal internal carotid arteries, as well as fetal heart rate (FHR), during normal feline gestation. Fifteen, 1-4 years of age, weighing 2.5-3.9kg, domestic short-hair pregnant queens, which were born in our institutional cat colony were included in this study. Color and pulsed-wave Doppler evaluations of uterine arteries were performed every 10 days (Day 0, 10, 20, 30, 40, 50, 60) from mating. Fetal Doppler and M-mode ultrasonography were performed to assess umbilical, fetal abdominal aorta, fetal renal, fetal internal carotid arteries and FHR. Both peak systolic velocity (PSV) and end diastolic velocity (EDV) of uterine artery increased up to parturition (P<0.01), while resistance index (RI) decreased from Day 10 onwards (P<0.01). From Day 40 onwards, RI of umbilical artery diminished, while PSV and EDV augmented (P<0.01). Fetal abdominal aorta (P<0.01), renal (P<0.01) and internal carotid (P<0.01) arteries diminished their RI from Days 40, 60 and 40 onwards, respectively. Both PSV and EDV of these three arteries increased progressively. Fetal heart rate was first registered on Day 20 when it began to increase up to Day 40 and then diminished to the end of gestation (P<0.01). It is concluded that blood flow of uterine, umbilical, fetal abdominal aorta, fetal renal and fetal internal carotid arteries progressively increased during normal feline pregnancy, while FHR rose to mid gestation and then decreased up to parturition.


Assuntos
Gatos/anatomia & histologia , Feto/irrigação sanguínea , Troca Materno-Fetal/fisiologia , Placenta/irrigação sanguínea , Útero/irrigação sanguínea , Animais , Aorta Abdominal/embriologia , Artérias/diagnóstico por imagem , Artéria Carótida Interna/embriologia , Gatos/fisiologia , Feminino , Frequência Cardíaca Fetal/fisiologia , Gravidez , Artéria Renal/embriologia , Ultrassonografia Doppler/veterinária , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/veterinária , Útero/diagnóstico por imagem , Resistência Vascular
10.
Anim Reprod Sci ; 126(1-2): 130-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21616613

RESUMO

The aim of this study was to describe the changes of uterine artery, umbilical artery and fetal abdominal aorta, renal and internal carotid arteries blood flow in abnormal canine pregnancy. Twenty-two, Brucella-negative pregnant bitches were retrospectively classified into abnormal (which had either interrupted their pregnancy between days 52 and 60 or had perinatal death >60% of the litter; n=11) and normal (which had delivered healthy puppies at term; n=11). In all the animals, color and pulsed-wave Doppler examinations of uterine artery were conducted every 10 days from Day 20 to 50 from estimated luteinizing hormone peak. Doppler ultrasonography was also conducted in the fetuses to assess umbilical artery, abdominal aorta, renal and internal carotid arteries from Day 40 to 60 of gestation. Throughout the study, resistance index (RI) of uterine, umbilical and fetal renal arteries decreased up to -15% compared to -36% (P<0.01), -11% compared to -23% (P<0.05) and 2% compared to -13% (P<0.05), respectively in the abnormal and normal bitches. Fetal abdominal aorta and internal carotid did not differ between groups (P>0.05). It is concluded that in dogs, uterine artery, umbilical artery and fetal renal artery RI differ between normal and abnormal gestation being useful for the prediction of adverse obstetric outcome.


Assuntos
Feto/irrigação sanguínea , Prenhez , Ultrassonografia Doppler/veterinária , Ultrassonografia Pré-Natal/veterinária , Artéria Uterina/diagnóstico por imagem , Aborto Animal , Animais , Animais Recém-Nascidos , Aorta Abdominal/diagnóstico por imagem , Cães , Feminino , Frequência Cardíaca Fetal , Gravidez , Artéria Renal/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos
11.
Injury ; 41(11): 1140-4, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20850743

RESUMO

Paediatric pelvic fractures are rare lesions. In the literature still controversy exists regarding the management of these injuries. The sequelae of these types of lesions has been described. We report the management and long term outcome of 8 patients with paediatric pelvic fractures treated in our institution. Associated injuries to the Risser's growth nuclei are described that has not been previously reported. Anatomical reduction of the displaced fracture should be considered to minimise the risk of long term functional impairment.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Ossos Pélvicos/lesões , Adolescente , Criança , Pré-Escolar , Feminino , Consolidação da Fratura/fisiologia , Fraturas Ósseas/fisiopatologia , Fraturas Ósseas/reabilitação , Humanos , Masculino , Recuperação de Função Fisiológica/fisiologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Theriogenology ; 66(6-7): 1557-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16458958

RESUMO

Cystic endometrial hyperplasia-pyometra (CEH-P) complex is a progesterone-dependent disease that requires medical treatment in bitches intended for breeding. To test the efficacy and safety of a combined protocol and to assess the effect of age, stage of cycle, previous steroid hormone administration and parity on treatment, 29 bitches diagnosed with CEH-P complex were treated daily with cabergoline 5 microg/kg PO and cloprostenol 1 microg/kg SC for 7-14 days, along with supportive antibiotic and hydration therapies. Before treatment, and on Days 3, 7 and 14, all bitches were evaluated clinically and uterine horn diameter measured during trans-abdominal ultrasonography. Twenty-four of 29 bitches were cured by either Day 7 or 14. Nine bitches had mild digestive side effects. Clinical signs related to pyometra began to improve markedly as early as Day 2 of treatment. Uterine diameters decreased (P < 0.05) by Day 3 of treatment, and continued to gradually decrease, reaching normal size by Day 14. Relapses occurred in 6 of 29 cases. Pregnancy was achieved in one of the two young bitches bred after treatment. No significant relationships were found between success rate and age, stage of the estrous cycle, previous hormone administration or parity. Although no variables affecting treatment results could be identified, this combination of compounds was found to be an efficient and safe for treatment of CEH-P.


Assuntos
Cloprostenol/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Agonistas de Dopamina/uso terapêutico , Hiperplasia Endometrial/veterinária , Ergolinas/uso terapêutico , Prostaglandinas Sintéticas/uso terapêutico , Animais , Cabergolina , Doenças do Cão/diagnóstico por imagem , Cães , Quimioterapia Combinada , Hiperplasia Endometrial/diagnóstico por imagem , Hiperplasia Endometrial/tratamento farmacológico , Hiperplasia Endometrial/patologia , Endometrite/diagnóstico por imagem , Endometrite/tratamento farmacológico , Endometrite/veterinária , Feminino , Ultrassonografia , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/tratamento farmacológico , Doenças Uterinas/veterinária
13.
J Mol Recognit ; 11(1-6): 243-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10076848

RESUMO

We reported previously that TG19318, a synthetic ligand deduced from the screening of combinatorial libraries, displays specific and selective recognition properties for immunoglobulins of the G class and can be used conveniently for affinity chromatography purification of monoclonal and polyclonal antibodies. In this study we have extended the ligand characterization, examining its ability to bind IgA from cell culture supernatants and from IgG-deprived serum. Affinity columns prepared by immobilizing TG19318 on Sepharose allowed convenient one-step purification of monoclonal IgA directly from crude feedstocks, in high yield and with full recovery of immunoreactivity. Optimal column adsorption occurred with phosphate buffer at neutral pH, while elution of adsorbed IgA could be accomplished by a buffer pH change to acidic or basic conditions. Column capacity was close to 7 mg IgA/ml support.


Assuntos
Marcadores de Afinidade , Cromatografia de Afinidade/métodos , Imunoglobulina A/isolamento & purificação , Adsorção , Animais , Anticorpos Monoclonais/isolamento & purificação , Biotecnologia , Soluções Tampão , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina G/isolamento & purificação , Ligantes , Camundongos
14.
Protein Expr Purif ; 7(4): 347-54, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8776751

RESUMO

Amidating mouse pituitary cells (AtT-20) have been engineered to secrete human calcitonin (hCT) in the fully active amidated form, without the need of additional enzymatic or chemical modifications. The 141-residue human calcitonin precursor has first been cloned in the eucaryotic expression vector pRc/RSV, and the resulting plasmid pRc/RSV/hCT introduced in AtT-20 cells. After transfection, 122 independent clones resistant to G-418 were selected and screened for calcitonin production using a competitive ELISA specifically designed to detect the amidated form of calcitonin. One of these clones was amplified and showed expression of 17 ng/ml of hCT, with a 70% increase in productivity after cAMP treatment. Calcitonin was partially purified from culture medium by two sequential steps of reverse-phase chromatography and characterized in terms of immunoreactivity and molecular weight by TOF-MALDI mass spectroscopy, which confirmed the intended chemical nature and the presence of the C-terminal amidated residue.


Assuntos
Calcitonina/biossíntese , Sequência de Aminoácidos , Animais , Ácido Ascórbico/farmacologia , Sequência de Bases , Bucladesina/metabolismo , Calcitonina/química , Calcitonina/genética , Calcitonina/isolamento & purificação , Células Cultivadas , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Primers do DNA/química , DNA Recombinante/genética , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos , Humanos , Soros Imunes/imunologia , Camundongos , Dados de Sequência Molecular , Hipófise/citologia , Hipófise/metabolismo , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta , Fatores de Tempo , Transfecção
15.
Am J Nephrol ; 14(4-6): 412-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7847477

RESUMO

Pliny the Elder described medicinal plants in books XX-XXVII of Naturalis Historia, reporting the therapeutic properties and preparations of the plants for use in different parts of the body. An exhibition of 20 plants chosen from those indicated for renal diseases is described.


Assuntos
Nefropatias/história , Fitoterapia/história , Plantas Medicinais , História Antiga , Humanos , Nefropatias/tratamento farmacológico , Cidade de Roma
16.
Am J Nephrol ; 14(4-6): 418-22, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7847478

RESUMO

The original De Materia Medica of Dioscorides has been lost, but several copies remain. Unlike the original, these contain an alphabetical listing of plants and color plates. The source for the plants described in this paper is a 16th century translation into vernacular Italian and the Codex Neapolitanus. In all, 12 plants listed by Dioscorides for treatment of renal diseases can be positively identified.


Assuntos
Nefropatias/história , Materia Medica/história , Plantas Medicinais , História Antiga , Humanos , Nefropatias/tratamento farmacológico , Sicília
17.
Conn Med ; 56(11): 607-10, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1490326

RESUMO

Six unusual surgical case are reported and the literature reviewed. The cases are: 1. Adenoid cystic carcinoma of the submaxillary gland 2. Parathyroid carcinoma 3. Squamous cell cancer of the pancreas 4. Leiomyosarcoma of the abdomen (two cases) 5. Myelolipoma of the adrenal gland These are representative cases from a general surgeon's practice, emphasizing the variety of interesting patients that the general surgeon cares for, and the scope of surgical knowledge that must be continually maintained. One of the attractions of having a practice in general surgery is that it provides the opportunity to diagnose and treat patients with a variety of conditions requiring surgical intervention. Reviewed here are six recent operative cases, their presentation, and management.


Assuntos
Neoplasias/cirurgia , Neoplasias Abdominais/cirurgia , Adulto , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
18.
Br J Rheumatol ; 29(1): 72-4, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2306577

RESUMO

Chronic arthritis, whether primary or reactive, is an unusual manifestation of long standing tuberculosis. We described the case of a 16-year-old gymnast with tuberculous rheumatism (Poncet's disease) secondary to Pott's disease of the dorsal spine. The possible pathogenetic mechanisms are discussed.


Assuntos
Ginástica , Doenças Reumáticas/etiologia , Tuberculose/complicações , Adolescente , Antituberculosos/uso terapêutico , Traumatismos em Atletas/diagnóstico , Doença Crônica , Erros de Diagnóstico , Feminino , Humanos , Radiografia , Doenças Reumáticas/diagnóstico por imagem , Tuberculose/tratamento farmacológico
19.
Nurs Forum ; 24(2): 8-12, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2628937

RESUMO

A computerized nursing system has many benefits for both the nursing staff and the hospital. Adequate planning and orientation are essential in order for nurses at the bedside to use the system and to reap its full benefits. The author gives an overview of some of the effects of nursing along with some applications to clinical practice that bear directly on staff nurses.


Assuntos
Sistemas de Informação , Enfermagem , Eficiência , Previsões , Humanos , Sistemas de Informação/economia , Sistemas de Informação/tendências , Diagnóstico de Enfermagem , Recursos Humanos de Enfermagem/provisão & distribuição , Admissão e Escalonamento de Pessoal
20.
Eur J Gynaecol Oncol ; 9(1): 1-4, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3278910

RESUMO

The author recalls the most important events in the life of George N. Papanicolaou, "the father of modern cytology", underlining the social message arising out of his scientific achievement and moral personality.


Assuntos
Feminino , Grécia , Ginecologia/história , História do Século XX , Humanos , Teste de Papanicolaou , Estados Unidos , Esfregaço Vaginal/história
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