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1.
Opt Lett ; 48(19): 5105-5108, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773396

RESUMO

Strongly correlated Stokes and anti-Stokes photon pairs (biphotons) exhibiting very large generation rates and spectral brightnesses could be attained at extremely low pump powers and optical depths. This is realized via spontaneous four-wave mixing in cold atoms with enhanced nonlocal (Rydberg) optical nonlinearities and prepared into a dark state with a large population imbalance. The scheme works with all light fields on resonance yet with negligible linear absorption and Raman gain.

2.
Br J Neurosurg ; 37(6): 1480-1486, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34180316

RESUMO

OBJECTIVES: Dural based Marginal Zone MALT-type B-Cell Lymphoma (MZBCL) is an intracranial tumor that can mimicking meningioma both from a clinical and a radiological point of view. A standard treatment protocol is still lacking. Aim of the present work is to provide an update of the present literature regarding this rare neoplasia. PATIENTS AND METHODS: We report the case of a patient with a dural-based lesion mimicking a meningioma of the tentorium. After surgical treatment, the diagnosis was of MZBCL. A literature review is performed to highlight the typical characteristics of this rare intracranial lesion and to define the best therapeutic approach. RESULTS: Literature review included 38 articles describing 126 cases of intracranial dural-based MZBCL. No clinical trial has been found. Clinical and histopathological features are properly collected to provide a guide for future cases. Different treatment options have been attempted. Combination of surgery with adjuvant radiation therapy is the most used option. CONCLUSIONS: MZBCL should be considered in differential diagnosis for dural-based intracranial lesion. Surgery followed by radiation therapy is the most reported treatment. As a consequence of the rarity of this disease, of its indolent progression and of the lack of adequate follow-up, it is not possible to define it is the best treatment option.


Assuntos
Neoplasias Encefálicas , Linfoma de Zona Marginal Tipo Células B , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/patologia , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Linfoma de Zona Marginal Tipo Células B/cirurgia , Diagnóstico Diferencial , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia
3.
Br J Neurosurg ; : 1-7, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35393903

RESUMO

Aplasia of the lumbar pedicle is a rare condition, frequently associated with low back pain. Its recognition is fundamental in the definition of the correct treatment. We performed a literature review in order to clarify how to best diagnose and treat this rare anatomical condition. A comprehensive literature search for studies published through October 2020 was performed, using the following algorithm: "aplasia" OR "aplastic" OR "hypoplasia" OR "hypoplastic" OR "absent" OR absence" AND "pedicle" AND "lumbar" OR "sacral" OR "lumbosacral". References from reviewed papers were further evaluated for the inclusion of other relevant studies. Eighteen studies were included in the systematic review for a total of 24 adult patients. Another case of left L5 pedicle aplasia treated at our hospital has been described and included in the present review. This anatomical condition may be suspected in plain x-Ray, but CT scan 3D reconstructions may help to confirm the diagnosis in equivocal cases. Low-back pain and radiculopathy are the main signs and symptoms. The treatment was described in 14 cases. Eight patients underwent surgical intervention. In cases with spondylolisthesis, fusion surgery was performed with different techniques, obtaining an excellent clinical outcome. Pedicular aplasia is a rare condition that must be recognized in patients with a low back. When it is associated with spondylolisthesis, fusion surgery should be the preferred option.

4.
Opt Express ; 29(4): 5890-5900, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726121

RESUMO

It is known that the Kramers-Kronig (KK) relation between real and imaginary parts of the optical susceptibility in the frequency domain can also be realized in the space domain, as first proposed in [Nat. Photonics9(7), 436 (2015)10.1038/nphoton.2015.106]. We here study a mechanism to implement spatial KK relations in a cold atomic sample and use it to control unidirectional reflectionless for probe light incident from either the left or right side of the sample at will. In our model, the complex frequency dependent atomic susceptibility is mapped into a spatially dependent one, employing a far-detuned driving field of intensity linearly varied in space. The reflection of an incident light from one side of the sample can then be set to vanish over a specific frequency band directly by changing the driving field parameters, such as its intensity and frequency. Also, by incorporating the Bragg scattering into the spatial KK relation, the reflectivity from the opposite side of the sample, though typically small for realistic atomic densities, can be made to increase to improve the reflectivity contrast. The present scheme bears potentials for all-optical network applications that require controllable unidirectional light propagation.

5.
Neurosurg Rev ; 44(3): 1779-1788, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32840722

RESUMO

The operative approach to the posterior incisural space is challenging because of its deep location, the surrounding eloquent areas, and the intimate relationship with the deep veins. Several approaches have been proposed to manage the lesions in this region: supratentorial, infratentorial and a combination of them. Brain retraction, injury to the occipital lobe and corpus callosum, and venous bleeding are the principle drawbacks of these routes. We performed anatomical dissection study using 10 embalmed human cadaver specimens injected with colored latex exploring a different route, parietal interhemispheric transfalcine transtentorial (PITT). Then we used a PITT approach on two patients with posterior incisural space (PIS) lesions. The PITT approach led to successful and safe complete removal of PIS lesions in our cases. No complications were reported. The present approach could be a valuable option in case of PIS lesions, especially those associated with downward displacement of the deep venous complex; thanks to the gravity it reduce the complications related to the occipital lobe retraction and manipulation. Moreover, cutting the superior-anterior edge of the tentorium, the sub-tentorial space could be reached.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/cirurgia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/cirurgia , Idoso , Cadáver , Dura-Máter/diagnóstico por imagem , Dura-Máter/cirurgia , Feminino , Humanos , Procedimentos Neurocirúrgicos/tendências
6.
Opt Express ; 28(21): 31076-31092, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33115090

RESUMO

We show that narrowband two-color entangled single Stokes photons can be generated in a ultra-cold atoms sample via selective excitation of two spontaneous four-wave mixing (SFWM) processes. Under certain circumstances, the generation, heralded by the respective common anti-Stokes photon, is robust against losses and phase-mismatching and is remarkably efficient owing to balanced resonant enhancement of the two four-wave mixing processes in a regime of combined induced transparency. Maximally color-entangled states can be easily attained by adjusting the detunings of the external couplings and driving fields, even when these are quite weak.

7.
J Biol Regul Homeost Agents ; 34(6 Suppl. 3): 69-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33412782

RESUMO

The fundamental moment of prosthetic rehabilitation is the "temporary". Although the meaning of the term diminishes its importance, the provisional has fundamental biological, aesthetic and functional functions. The oral cavity must maintain an adequate level of oral hygiene to carry out this delicate phase in the best possible way; a result achieved only with the collaboration of the prosthetic dentist with the hygienist and the patient, as if they were a biological system in motion. The different methods of hygiene are effective in maintaining a good level of oral health; but they could, if too aggressive, affect the prosthetic restoration. Our objective in vitro is to understand, after applying a known bacterial load, which hygiene method is the most effective in removing bacterial biofilm but at the same time is less aggressive towards resinous material.


Assuntos
Coroas , Biofilmes , Saúde Bucal
9.
Phys Rev Lett ; 113(12): 123004, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25279626

RESUMO

Light propagation in optical lattices of driven cold atoms exhibits non-Hermitian degeneracies when the first-order modulation amplitudes of real and imaginary parts of the probe susceptibility are manipulated to be balanced. At these degeneracies, one may observe complete unidirectional reflectionless light propagation. This strictly occurs with no gain and can be easily tuned and fully reversed as supported by the transfer-matrix calculations and explained via a coupled-mode analysis.

10.
Phys Rev Lett ; 110(22): 223602, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23767722

RESUMO

Reciprocity is fundamental to light transport and is a concept that holds also in rather complex systems. Yet, reciprocity can be switched off even in linear, isotropic, and passive media by setting the material structure into motion. In highly dispersive multilayers this leads to a fairly large forward-backward asymmetry in the pulse transmission. Moreover, in multilevel systems, this transport phenomenon can be all-optically enhanced. For atomic multilayer structures made of three-level cold 87Rb atoms, for instance, forward-backward transmission contrast around 95% can be obtained already at atomic speeds in the meter per second range. The scheme we illustrate may open up avenues for optical isolation that were not previously accessible.

11.
Stem Cells Int ; 2022: 2454168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035489

RESUMO

Chondropathies are increasing worldwide, but effective treatments are currently lacking. Mesenchymal stromal cell (MSCs) transplantation represents a promising approach to counteract the degenerative and inflammatory environment characterizing those pathologies, such as osteoarthritis (OA) and rheumatoid arthritis (RA). Umbilical cord- (UC-) MSCs gained increasing interest due to their multilineage differentiation potential, immunomodulatory, and anti-inflammatory properties as well as higher proliferation rates, abundant supply along with no risks for the donor compared to adult MSCs. In addition, UC-MSCs are physiologically adapted to survive in an ischemic and nutrient-poor environment as well as to produce an extracellular matrix (ECM) similar to that of the cartilage. All these characteristics make UC-MSCs a pivotal source for a stem cell-based treatment of chondropathies. In this review, the regenerative potential of UC-MSCs for the treatment of cartilage diseases will be discussed focusing on in vitro, in vivo, and clinical studies.

12.
Phys Rev Lett ; 107(4): 043602, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21867003

RESUMO

The force exerted on a material by an incident beam of light is dependent upon the material's velocity in the laboratory frame of reference. This velocity dependence is known to be difficult to measure, as it is proportional to the incident optical power multiplied by the ratio of the material velocity to the speed of light. Here we show that this typically tiny effect is greatly amplified in multilayer systems composed of resonantly absorbing atoms exhibiting ultranarrow photonic band gaps. The amplification effect for optically trapped 87Rb is shown to be as much as 3 orders of magnitude greater than for conventional photonic-band-gap materials. For a specific pulsed regime, damping remains observable without destroying the system and significant for material velocities of a few ms(-1).

13.
Eur Rev Med Pharmacol Sci ; 24(8): 4572-4575, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32373997

RESUMO

OBJECTIVE: The recent outbreak of SARS-CoV-2 greatly involves the resources of the global healthcare system, as it affects newborns, adults, and elders. This infection runs in three major stages: a mild cold-like illness, a moderate respiratory syndrome and a severe acute interstitial pneumonia. SARS-CoV-2 infection seems to have a more benign evolution in children. As a matter of fact, low susceptibility and minor aggressivity have been highlighted in most cases. There are currently no effective antiviral drugs treatment for the affected children. No sufficient results have been reached by the use of interferon (IFN), lopinavir/ritonavir, orbidol, and oseltamivir in the treatment of the coronaviruses infection. The aim of this short review is to highlight the differences existing between COVID-19 cases in adults and children.


Assuntos
Fatores Etários , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Adulto , Betacoronavirus , COVID-19 , Criança , Infecções por Coronavirus/epidemiologia , Humanos , Pandemias , Pneumonia Viral/epidemiologia , SARS-CoV-2
14.
Clin Neurol Neurosurg ; 197: 106180, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32877767

RESUMO

OBJECTIVES: Cavernous malformations (CM) are low-flow vascular lesions that can cause significant symptoms and neurological deficits. Different intraoperative surgical approaches have been developed. Aim of the present investigation is the comparison between the trans-sulcal approach (TS) and the trans-parenchymal neuronavigation-assisted approach (TPN) in a surgical series from two neurosurgical centers. The technique and clinical outcomes are discussed, with a specific focus on seizure outcome. PATIENTS AND METHODS: Clinical and radiological data from two neurosurgical centers ("A. Gemelli" Hospital in Rome and A.O.U. Città della Salute e della Scienza in Turin) were retrospectively reviewed in order to evaluate the different outcome of TS and TPN approach for cavernous malformation treatment. RESULTS: A total of 177 patients underwent surgical intervention for supratentorial CM, 130 patients with TPN approach and 47 with TS approach. TS approach was associated with higher rate of seizure in early post-operative period both in epileptic patients (p < 0,001) and in patients without history of seizures before surgery (p = 0,002). Moreover, length of incision (p < 0,001), area of craniotomy (p < 0,001) and corticectomy (p < 0,001) were bigger in TS than in TPN approach. Brain contusion (p < 0,001) and fluid collection (p < 0,001) were more likely to be discovered after TS approach. CONCLUSIONS: TPN is a valuable approach for resection of CM. Minor complications are significantly lower in TPN approach when compared with TS approach. In addition, it is associated with lower rate of early post-operative seizure and shorter length of stay.


Assuntos
Neoplasias do Sistema Nervoso Central/cirurgia , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Craniotomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
15.
Eur Rev Med Pharmacol Sci ; 24(7): 3849-3875, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32329861

RESUMO

The increasing incidence of chronic pathologies and especially non-AIDS defining cancers, such as lung cancer, hepatocellular carcinoma, breast cancer, colorectal cancer, prostate cancer, and Hodgkin's lymphoma after the introduction of combined antiretroviral therapy requires the infectious diseases specialist to know how and when to suspect and diagnose cancer in people living with HIV. The aim of this review is to provide updated studies and information about non-AIDS defining cancers and their management in PLWH sheading a light on possible futures scenarios.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Neoplasias/diagnóstico , Neoplasias/terapia , Humanos , Neoplasias/complicações
18.
Histopathology ; 52(2): 203-12, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18184269

RESUMO

AIMS: CD1a is a molecule belonging to the highly conserved group of CD1 proteins. Its expression in dendritic cells is related to the presentation of tumour-derived glycolipid antigens to T cells and, consequently, the development of a successful antitumour response. The aim was to investigate the presence of CD1a+ cells in both primary tumours and lymph nodes (LN) of a series of 35 invasive ductal carcinomas by both immunohistochemistry and reverse transcription-polymerase chain reaction. METHODS AND RESULTS: CD1a antigen was more expressed in N0 than N1 breast cancer (P < 0.0001) in both primary lesions and LN metastases and correlated positively and significantly with oestrogen (ER) (P = 0.0025) and progesterone (P = 0.0226) receptor (PR) status, as well as CD4+ and CD8+ T-lymphocyte infiltration. CONCLUSIONS: This is the first report to show a link between CD1a+ mononuclear cells in breast cancer and in paired LN metastases. The positive and significant correlations between the number of CD1a+ cells and positivity of the primary tumour for ER and PR suggest a possible role for CD1a as a prognostic marker for breast cancer, raising the possibility that hormone receptor-positive breast cancer patients may have a better prognosis in the presence of greater dendritic cell infiltration.


Assuntos
Antígenos CD1/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Regulação para Baixo , Metástase Linfática/diagnóstico , Adulto , Idoso , Antígenos CD1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Células Dendríticas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Metástase Linfática/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
19.
Clin Neurol Neurosurg ; 170: 120-126, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29777944

RESUMO

Glioblastoma (GBM) is the most common glioma in adults, with incidence increasing by 3% per year. According to the World Health Organization Classification of Central Nervous System Tumors, GBM is considered a grade IV tumor due to its malignant behavior. The aim of this review is to summarize the main biological aspects of GBM. In particular, we focused our attention on those alterations which have been proven to have an impact on patients' outcome, mainly in terms of overall survival (OS), or on the tumor response to therapies. We have also analyzed the cellular biology and the interactions between GBM and the surrounding environment.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Gerenciamento Clínico , Glioblastoma/diagnóstico , Glioblastoma/genética , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/terapia , Receptores ErbB/sangue , Receptores ErbB/genética , Glioblastoma/terapia , Humanos , Proteínas Proto-Oncogênicas B-raf/sangue , Proteínas Proto-Oncogênicas B-raf/genética
20.
Eur J Histochem ; 51 Suppl 1: 101-3, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17703600

RESUMO

During embryonic development, a pool of cells may become a reserve of undifferentiated cells, the embryo-stolen adult stem cells (ESASC). ESASC may be responsible for adult tissue homeostasis, as well as disease development. Transdifferentiation is a sort of reprogramming of ESASC from one germ layer-derived tissue towards another. Transdifferentiation has been described to take place from mesoderm to ectodermal- or endodermal-derived tissues and viceversa but not from ectodermal- to endodermal-derived tissues. We hypothesise that two different populations of ESASC could exist, the first ecto/mesoblast-committed and the second endo/mesoblast-committed. If confirmed, this hypothesis could lead to new studies on the molecular mechanisms of cell differentiation and to a better understanding of the pathogenesis of a number of diseases.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Adultas/fisiologia , Embrião de Mamíferos/citologia , Transplante de Células-Tronco , Ferimentos e Lesões/terapia , Adulto , Diferenciação Celular , Linhagem da Célula , Embrião de Mamíferos/fisiologia , Humanos , Mesoderma/citologia , Mesoderma/fisiologia
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