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1.
Nat Mater ; 23(7): 920-927, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38760518

RESUMO

Spin qubits defined by valence band hole states are attractive for quantum information processing due to their inherent coupling to electric fields, enabling fast and scalable qubit control. Heavy holes in germanium are particularly promising, with recent demonstrations of fast and high-fidelity qubit operations. However, the mechanisms and anisotropies that underlie qubit driving and decoherence remain mostly unclear. Here we report the highly anisotropic heavy-hole g-tensor and its dependence on electric fields, revealing how qubit driving and decoherence originate from electric modulations of the g-tensor. Furthermore, we confirm the predicted Ising-type hyperfine interaction and show that qubit coherence is ultimately limited by 1/f charge noise, where f is the frequency. Finally, operating the qubit at low magnetic field, we measure a dephasing time of T 2 * = 17.6 µs, maintaining single-qubit gate fidelities well above 99% even at elevated temperatures of T > 1 K. This understanding of qubit driving and decoherence mechanisms is key towards realizing scalable and highly coherent hole qubit arrays.

2.
Dalton Trans ; 44(8): 3633-9, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25470362

RESUMO

The interactions of three representative gold(III) complexes with human telomeric DNA sequences were analysed using a variety of biophysical methods, including DNA melting, circular dichroism, SPR and ESI MS; remarkable interactions were highlighted for all tested complexes, although they were associated to significantly different binding profiles. The most interesting compound was Auoxo6, a dinuclear gold(III) complex, which beyond manifesting a conspicuous binding affinity for the G-quadruplex conformation, turned out to be very effective in inducing a non-canonical secondary structure. These findings may clear the way for novel biological and pharmacological applications of this class of metal compounds.


Assuntos
Complexos de Coordenação/química , Quadruplex G , Ouro/química , Dicroísmo Circular , Complexos de Coordenação/síntese química , Humanos , Conformação de Ácido Nucleico , Espectrometria de Massas por Ionização por Electrospray , Ressonância de Plasmônio de Superfície
3.
Mycoses ; 52(1): 67-71, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18498297

RESUMO

Fourteen cases of dermatophytosis caused by Microsporum gypseum, representing 6.8% of all dermatophytic infections reported, were diagnosed in Siena, Italy, between 2005 and 2006. There were as follows: six cases of tinea corporis, one case of tinea corporis associated with tinea capitis, one case of tinea corporis associated with tinea barbae, one kerion on the head, one tinea cruris, one tinea faciei, one tinea barbae, two onychomycosis. In the three subjects with tinea corporis, the clinical appearance was impetigo-like, psoriasis-like and pityriasis rosea-like respectively. In another case, the lesion was indicative of tinea imbricata. The diagnosis was based on mycological examination. In six cases, the source of infection was a cat, whereas in the others it was contact with soil.


Assuntos
Dermatomicoses/epidemiologia , Microsporum/isolamento & purificação , Adolescente , Adulto , Animais , Doenças do Gato/transmissão , Gatos , Criança , Pré-Escolar , Dermatomicoses/transmissão , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Unhas/microbiologia , Unhas/patologia , Pele/microbiologia , Pele/patologia , Microbiologia do Solo
4.
Lymphology ; 41(1): 29-39, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18581956

RESUMO

We investigated lymphatic morphology and expression of endothelin (ET-1) axis molecules in human eyelids affected by an inflammatory state (chalazion) and an age-related degenerative condition (dermatochalasis). Lymphatics were immunohistologically detected by D2-40/LYVE-1 staining. Absorbing lymphatic vessels were localized in papillary dermis and around skin appendages with distinctive morphology. In chalazion, D2-40 reactive flattened lymphatic profiles were compressed by inflammatory infiltrate; in dermatochalasis, large fully opened lymphatics were observed, with a significantly wider total area (lymphatic lumina/200x field; p < 0.05). The lymphatic density (number/200x field) in the two groups was within the same range. Lymphatic dilation is possibly dependent on reduction and fragmentation of the dermal elastic network as well as of oxytalanic fibers in the papillary dermis of dermatochalasis, as shown by Weigert's reaction. Multifunctional peptide ET-1, involved in vasomotion, inflammation and connective proliferation, was faintly and discontinuously localized on lymphatics, as was its type A receptor. In contrast, the consistent expression of type B receptor indicates that lymphatic endothelium is a physiological target for ET-1, whose effects are modulated by multiple pathophysiological conditions. Thus, vasoactive factors play a role in the physiology of richly vascularized eyelids, and therefore, morphofunctional characterization of lymphatic vessels may be useful in suggesting treatment options.


Assuntos
Calázio/patologia , Doenças Palpebrais/patologia , Pálpebras/patologia , Vasos Linfáticos/patologia , Adulto , Idoso , Anticorpos Monoclonais/análise , Anticorpos Monoclonais Murinos , Calázio/metabolismo , Endotelina-1/análise , Doenças Palpebrais/metabolismo , Pálpebras/química , Feminino , Humanos , Imuno-Histoquímica , Vasos Linfáticos/química , Masculino , Pessoa de Meia-Idade , Proteínas de Transporte Vesicular/análise
5.
Br J Pharmacol ; 153(8): 1706-17, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18297103

RESUMO

BACKGROUND AND PURPOSE: Evidence is accumulating to support a role for interleukin-1beta (IL-1beta) in astrocyte proliferation. However, the mechanism by which this cytokine modulates this process is not fully elucidated. EXPERIMENTAL APPROACH: In this study we used human astrocytoma U-373MG cells to investigate the role of nitric oxide (NO), intracellular Ca(2+) concentration ([Ca(2+)](i)), and extracellular signal-regulated protein kinase (ERK) in the signalling pathway mediating IL-1beta-induced astrocyte proliferation. KEY RESULTS: Low IL-1beta concentrations induced dose-dependent ERK activation which paralleled upregulation of cell division, whereas higher concentrations gradually reversed both these responses by promoting apoptosis. Pretreatment with the nonspecific NOS inhibitor, N-omega-nitro-l-arginine methyl ester (L-NAME) or the selective iNOS inhibitor, N-[[3-(aminomethyl)phenyl]methyl]-ethanimidamide dihydrochloride (1400W), antagonized ERK activation and cell proliferation induced by IL-1beta. Inhibition of cGMP formation by the guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), partially inhibited ERK activation and cell division. Functionally blocking Ca(2+) release from endoplasmic reticulum with ryanodine or 2-aminoethoxydiphenylborane (2-APB), inhibiting calmodulin (CaM) activity with N-(6-aminohexyl)-5-chloro-1-naphthalenesulphonamide hydrochloride (W7) or MAPK kinase activity with 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthiol]butadiene (U0126) downregulated IL-1beta-induced ERK activation as well as cell proliferation. The cytokine induced a transient and time-dependent increase in intracellular NO levels which preceded elevation in [Ca(2+)](i). CONCLUSIONS AND IMPLICATIONS: These data identified the NO/Ca(2+)/CaM/ERK signalling pathway as a novel mechanism mediating the mitogenic effect of IL-1beta in human astrocytes. As astrocyte proliferation is a hallmark of reactive astrogliosis, our results reveal a new potential target for therapeutic intervention in neuroinflammatory disorders.


Assuntos
Regulação da Expressão Gênica , Interleucina-1beta/fisiologia , Transdução de Sinais , Astrocitoma/metabolismo , Cálcio/metabolismo , Calmodulina/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Mitose/fisiologia , Óxido Nítrico/metabolismo , Fatores de Tempo
6.
Histol Histopathol ; 22(12): 1343-54, 2007 12.
Artigo em Inglês | MEDLINE | ID: mdl-17701914

RESUMO

Endothelin-1 (ET-1), a potent vasoconstrictor peptide, is involved in several functions of eye pathophysiology, such as regulation of intraocular tension and retinal reactive vasoconstriction. As ET-1 pro-inflammatory and fibrosing activity is emerging in different fields of pathology, we investigated the expression of ET-1 and endothelin-converting enzyme-1 (ECE-1) in chalazia, granulomatous lesions of the eyelid. ET-1 and ECE-1 were analyzed by immunohistochemistry (IHC) in twenty surgically removed chalazia, with regard to expression in eyelid structures and inflammatory infiltrate. Phenotype of ET-1 expressing inflammatory cells was established by double immunofluorescence. The cellular localization of prepro-ET-1 (pp-ET-1) mRNA and ECE-1 mRNA was studied by nonisotopic in situ hybridization (ISH). Neutrophils (PMNs), macrophages and T-lymphocytes were scattered in stroma, around alveoli and grouped in lipogranulomas. PMNs, macrophages, basal epithelium of meibomian adenomers and central ducts immunostained for ET-1. ECE-1 protein was found in meibomian adenomers, conjunctival epithelium, tarsal mucous glands and in inflammatory cells. Hybridization signals for pp-ET-1 mRNA and ECE-1 mRNA were recognized in healthy and degenerating meibomian ducts, adenomers, inflammatory cells, as well as in vessel walls. ECE-1 mRNA was also present in conjunctival epithelium and Henle's crypts. Our findings suggest that the multifunctional peptide ET-1 may have a role in molecular genesis of tissue damage in chalazia. ET-1 cytokine activity is likely to support the migration of inflammatory cells and the setting of lipogranulomas; ET-1 stimulation might contribute to proliferation of fibroblasts and collagen synthesis. ET-1 upregulation on meibomian adenomers and ducts may further enhance granulomas formation by stimulating lipid release.


Assuntos
Ácido Aspártico Endopeptidases/biossíntese , Endotelina-1/biossíntese , Pálpebras/metabolismo , Granuloma/metabolismo , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Metaloendopeptidases/biossíntese , Adolescente , Adulto , Idoso , Enzimas Conversoras de Endotelina , Feminino , Regulação da Expressão Gênica , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade
7.
Mycoses ; 50(2): 150-2, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17305781

RESUMO

We report the case of a 36-year-old Senegalese male with non-scarring alopecia of the scalp, including nodules and pustules, diagnosed as tinea capitis caused by Trichophyton soudanense. This dermatophyte is endemic in Central Africa and is becoming more frequent in Europe because of immigration. It has seldom been isolated in Italy. Tinea capitis is common in childhood and it is rare in adults, in which female sex is preferred. In adults, alopecic patches have to be distinguished from those due to other dermatoses inducing alopecia.


Assuntos
Infecções Bacterianas/diagnóstico , Foliculite/diagnóstico , Tinha do Couro Cabeludo/diagnóstico , Tinha do Couro Cabeludo/patologia , Trichophyton/isolamento & purificação , Adulto , Alopecia/microbiologia , Diagnóstico Diferencial , Humanos , Hifas/ultraestrutura , Itália , Masculino , Microscopia Eletrônica de Varredura , Tinha do Couro Cabeludo/microbiologia
8.
Mycoses ; 50(1): 82-4, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17302755

RESUMO

A case of primary subcutaneous zygomycosis due to Rhizopus oryzae is described in a 71-year-old man with normal immune status. Diagnosis was based on histological examination and culture of biopsy fragments from skin lesions. The patient recovered after itraconazole therapy (200 mg day(-1) for 60 days followed by 100 mg day(-1) for 45 days).


Assuntos
Dermatomicoses/diagnóstico , Mucormicose/diagnóstico , Rhizopus/isolamento & purificação , Idoso , Dermatomicoses/imunologia , Dermatomicoses/microbiologia , Dermatomicoses/patologia , Humanos , Masculino , Mucormicose/imunologia , Mucormicose/microbiologia , Mucormicose/patologia , Rhizopus/classificação , Tela Subcutânea/microbiologia
9.
Lymphology ; 39(4): 171-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17319628

RESUMO

Lymphatics were detected in the epineurium of the human sural nerve by D-240 immunostaining and confirmed by ultrastructural examination.


Assuntos
Anticorpos Monoclonais , Vasos Linfáticos/anatomia & histologia , Nervo Sural/anatomia & histologia , Anticorpos Monoclonais Murinos , Humanos , Técnicas Imunoenzimáticas , Vasos Linfáticos/ultraestrutura , Nervo Sural/ultraestrutura
10.
Mycoses ; 48(5): 343-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16115106

RESUMO

Consecutive cases of tinea faciei diagnosed in Siena between 1989 and 2003 were studied retrospectively for differences in clinical form, demographic data and species of dermatophyte isolated. The series consisted of 84 cases (59 females, 25 males) with a mean age of 27 years. Mean age of females (32.4 years) was significantly greater than that of males (14.2 years). The dermatophytes most frequently isolated were Microsporum canis (38 cases) and Trichophyton rubrum (31 cases). Clinical form was typical of tinea in 54 subjects (64.3%) and was tinea incognito because of inappropriate therapy in the other 30 (35.7%) subjects. The mean age of patients with the typical form (19.2 years) was significantly lower than that of those with tinea incognito (41.1 years). All cases in the age range 6-15 years had typical tinea, whereas the maximum frequency of cases with tinea incognito was 46-50 years. In the group with tinea incognito there was a majority of women and the dermatophytes isolated differed with gender. No such difference was observed in the group with typical tinea.


Assuntos
Dermatomicoses/epidemiologia , Microsporum/imunologia , Tinha/epidemiologia , Trichophyton/isolamento & purificação , Adolescente , Adulto , Dermatomicoses/microbiologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores Sexuais , Tinha/microbiologia
11.
Mycoses ; 47(7): 346-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15310343

RESUMO

A case of disto-lateral onychomycosis of the third toe of the right foot of a 45-year-old man is reported. The agent of infection was Ulocladium botrytis, a mycete not hitherto reported to infect humans. The patient underwent mycological examination consisting of direct microscope observation and culture of pathological material. Diagnosis was based on the macro- and microscopic characteristics of the colonies. Fragments of the latter were also examined by scanning electron microscope. Clinical and mycological recovery was achieved after 3 months of topical therapy with ciclopiroxolamine.


Assuntos
Ascomicetos/isolamento & purificação , Dermatoses do Pé/microbiologia , Onicomicose/microbiologia , Dermatoses do Pé/diagnóstico , Humanos , Masculino , Onicomicose/diagnóstico
12.
Mycoses ; 45(9-10): 368-72, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12421283

RESUMO

Immunohistochemical study of inflammatory infiltrate was carried out in five cases of subcutaneous phaeohyphomycosis before and after therapy. The infections were due to the genus Alternaria in four cases and genus Cladosporium in one. In four cases, infiltrating T cells with helper memory phenotype were slightly more abundant after therapy (70-80% versus 75-90% of T lymphocytes) and those with suppressor cytotoxic phenotype were slightly less abundant (20-25% versus 10-15%). In one case, CD8+, Tia-1+ lymphocytes constituted 50% of the T-cell infiltrate before and after therapy. In all cases, the infiltrate contained many CD79 a+ plasma cells, which increased slightly after therapy, and a high CD1a positivity of dendritic cells (presumably Langerhans cells) before and after therapy. The CD1a+ cells were detected in the epidermis and in granulomatous infiltrate; in the dermis and subcutis, many were close to fungal structures. In four cases, intra-epidermal CD1a+ cell number was slightly lower than in control skin. CD68+ cells were not found in the epidermis.


Assuntos
Células Gigantes/patologia , Linfócitos/patologia , Micoses/patologia , Dermatopatias/patologia , Pele/patologia , Humanos , Técnicas Imunoenzimáticas , Linfócitos/imunologia , Micoses/tratamento farmacológico , Micoses/imunologia , Pele/imunologia , Dermatopatias/tratamento farmacológico , Dermatopatias/imunologia
13.
Mycoses ; 45(1-2): 45-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11856437

RESUMO

A case of rhinocerebral zygomycosis due to Rhizopus oryzae, arising after trauma in a 53-year-old diabetic man, is reported. Diagnosis was based on histological and mycological examination. Fragments of the colonies were observed by scanning electron microscopy. This is the first case diagnosed in Tuscany.


Assuntos
Encefalopatias/microbiologia , Traumatismos Faciais/complicações , Mucormicose/microbiologia , Doenças Nasais/microbiologia , Doenças Profissionais/complicações , Rhizopus/isolamento & purificação , Encefalopatias/diagnóstico , Complicações do Diabetes , Evolução Fatal , Humanos , Itália , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
14.
Mycoses ; 44(7-8): 334-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11714072

RESUMO

Dermatophyte infections due to Trichopkyton verrucosum are not frequent in Europe. Six cases observed in Italy in the period 1995-99 are reported. Two were cases of tinea barbae, two of tinea corporis and two of tinea capitis, one of which had been preceded by tinea faciei. In three cases the source of contagion was horses, in two it was cattle and in one case it was another person. The two cases of tinea barbae were initially interpreted and treated as bacterial infections, a diagnostic error reported with increasing frequency in the literature regarding dermatophytosis due to T. verrucosum.


Assuntos
Tinha/diagnóstico , Trichophyton/isolamento & purificação , Adolescente , Adulto , Animais , Bovinos , Diagnóstico Diferencial , Cavalos , Humanos , Masculino , Pele/patologia , Tinha/transmissão , Tinha/veterinária
16.
Life Sci ; 69(8): 961-8, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11488408

RESUMO

Ten handball players, members of the Italian National Team (aged 20-25 years), were studied in two sessions corresponding to different performance levels. The first session occurred one week after the end of the regular season of the Italian Handball Federation: it corresponded to the beginning of the training cycle for the European Handball Championship. The second session occurred ten weeks after the first session. During this period, training consisted of 3 weeks of active recovery and 7 weeks of increasing workload. For each session, jumping performances (maximal height in a single jump, average mechanical power for a 15-s set of consecutive jumps) were evaluated. Venous blood samples were collected in resting conditions immediately before jumping performances to assess cortisol and testosterone plasma concentrations and glucocorticoid receptors (GcR) binding capacity and affinity in peripheral blood mononuclear cells (PBMCs). All the parameters, except GcR binding affinity, increased in the second session. The trends of variation in jumping performances, steroid hormone levels and GcR binding capacity were similar. For testosterone, this agrees with the hypothesis that an adequate level of this hormone is a prerequisite for improvement in explosive performances. For cortisol, higher GcR binding capacity after 10 weeks of training (with respect to initial values) indicated an up-regulation of GcR concomitant with the increase in hormone levels and performances. These findings suggest that the adaptation to training, confirmed by the improvement in performance, is characterized by a high value of GcR binding capacity and that it is mediated, among other factors, by the hormone levels and up-regulation of the receptors.


Assuntos
Monócitos/metabolismo , Receptores de Glucocorticoides/sangue , Esportes/fisiologia , Adulto , Humanos , Hidrocortisona/sangue , Itália , Masculino , Aptidão Física/fisiologia , Testosterona/sangue
17.
Mycoses ; 44(3-4): 83-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11413928

RESUMO

To determine whether there is a higher frequency of mycotic infections due to dermatophytes in diabetics, 171 diabetic outpatients and 276 controls were recruited in the period 1997-98. Patients with suspicious lesions underwent mycological examination which was positive in seven diabetics and 17 controls. In diabetics the most frequent infection was tinea pedis, followed by distal subungual onychomycosis; the most frequently isolated fungus was Trichophyton mentagrophytes. The results of the study did not show a prevalence of dermatophyte infections in diabetics. No correlation was found between dermatophytosis and duration or type of diabetes and its complications, blood sugar levels or levels of glycosylated haemoglobin. None of the diabetic patients with dermatophytosis had complications related to diabetes and basal blood sugar and glycosylated haemoglobin levels indicated good metabolic control.


Assuntos
Dermatomicoses/complicações , Complicações do Diabetes , Doenças da Unha/complicações , Trichophyton , Adulto , Idoso , Idoso de 80 Anos ou mais , Dermatomicoses/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças da Unha/epidemiologia , Onicomicose/complicações , Onicomicose/epidemiologia , Prevalência , Tinha dos Pés/complicações , Tinha dos Pés/epidemiologia
18.
Am J Reprod Immunol ; 45(4): 217-25, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11327548

RESUMO

PROBLEM: Plasma interferon (IFN)-beta levels, lymphocyte responsiveness, and evaluation of the relationship between circulating antiviral activity (AA) and IFN-gamma production were studied in pregnant women and nonpregnant age-matched controls with the objective of elucidating the downregulation of IFN-gamma production in successful pregnancy. METHOD OF STUDY: In plasma and supernatants of peripheral blood mononuclear cell (PBMC) cultures, stimulated with staphylococcal enterotoxin A (SEA) superantigen, from 43 pregnant women with a history of normal pregnancy and 30 healthy nonpregnant age-matched controls, levels of AA were measured in a micromethod by inhibition of the cytopathic effect (CPE) caused by vesicular stomatitis virus (VSV) in the human amnionic cell line (WISH). RESULTS: Significantly higher plasma AA (60% was IFN-gamma and residual activity was acid-labile IFN-like) was present in pregnant women than controls. On the other hand, SEA-activated PBMCs from pregnant women produced significantly lower IFN-gamma levels than those of nonpregnant women. Furthermore, maternal plasma AA levels correlated negatively with IFN-gamma production by SEA-stimulated PBMCs. CONCLUSION: The hypothesis that successful pregnancy requires downregulation of IFN-gamma is only partially sustained, suggesting that the immunology of pregnancy is more complex and that murine and human pregnancy have different cytokine profiles.


Assuntos
Antivirais/sangue , Interferon gama/sangue , Ativação Linfocitária/imunologia , Gravidez/imunologia , Adulto , Feminino , Humanos , Resultado da Gravidez , Trimestres da Gravidez/imunologia , Superantígenos/imunologia
20.
Mycoses ; 43(5): 169-72, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10948813

RESUMO

We describe 45 cases of dermatophytosis due to Trichophyton violaceum diagnosed in Tuscany from 1985 to 1997. Diagnosis was based on direct microscope mycological examination and culture. Nine of the 45 patients were Italian, eight of whom were born and resident in Tuscany; the others were Africans who contracted the infection in their country of origin. The first case in a non-European was observed in 1985, but since 1991 isolation from foreigners has become more frequent. The increase in cases of infection by T. violaceum in our region is certainly linked to immigration. The cases of epidermomycosis in Tuscans suggests that the fungus has already become autochthonous.


Assuntos
Tinha/epidemiologia , Tinha/microbiologia , Trichophyton/isolamento & purificação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade
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