Biphoton generation enhanced by nonlocal nonlinearity via Rydberg interactions.

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.

Intracranial dural based marginal zone MALT-type B-cell lymphoma: a case - Based update and literature review.

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.

Lumbo-sacral pedicular aplasia diagnosis and treatment: a systematic literature review and case report.

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.

Umbilical Cord Mesenchymal Stromal Cells for Cartilage Regeneration Applications.

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.

Controlled unidirectional reflection in cold atoms via the spatial Kramers-Kronig relation.

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.

Parietal interhemispheric transfalcine transtentorial approach for posterior incisural space lesions: from the lab to the operative room.

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.

Efficient generation of heralded narrowband color-entangled states.

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.

Trans-sulcal versus trans-parenchymal approach in supratentorial cavernomas. A multicentric experience.

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.

Outbreak of COVID-19 infection in children: fear and serenity.

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.

Non-AIDS defining cancers: a comprehensive update on diagnosis and management.

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.

Management of the delicate phase of the temporary crown: an in vitro study.

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.

The post-surgical era of GBM: How molecular biology has impacted on our clinical management. A review.

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.

Preliminary experience with 4K ultra-high definition endoscope: analysis of pros and cons in skull base surgery.

During the last two decades endoscopic skull base surgery observed a continuous technical and technological development 3D endoscopy and ultra High Definition (HD) endoscopy have provided great advances in terms of visualisation and spatial resolution. Ultra-high definition (UHD) 4K systems, recently introduced in the clinical practice, will shape next steps forward especially in skull base surgery field. Patients were operated on through transnasal transsphenoidal endoscopic approaches performed using Olympus NBI 4K UHD endoscope with a 4 mm 0° Ultra Telescope, 300 W xenon lamp (CLV-S400) predisposed for narrow band imaging (NBI) technology connected through a camera head to a high-quality control unit (OTV-S400 - VISERA 4K UHD) (Olympus Corporation, Tokyo, Japan). Two screens are used, one 31" Monitor - (LMD-X310S) and one main ultra-HD 55" screen optimised for UHD image reproduction (LMD-X550S). In selected cases, we used a navigation system (Stealthstation S7, Medtronic, Minneapolis, MN, US). We evaluated 22 pituitary adenomas (86.3% macroadenomas; 13.7% microadenomas). 50% were not functional (NF), 22.8% GH, 18.2% ACTH, 9% PRL-secreting. Three of 22 were recurrences. In 91% of cases we achieved total removal, while in 9% near total resection. A mean follow-up of 187 days and average length of hospitalisation was 3.09 ± 0.61 days. Surgical duration was 128.18± 30.74 minutes. We experienced only 1 case of intraoperative low flow fistula with no further complications. None of the cases required any post- or intraoperative blood transfusion. The visualisation and high resolution of the operative field provided a very detailed view of all anatomical structures and pathologies allowing an improvement in safety and efficacy of the surgical procedure. The operative time was similar to the standard 2D HD and 3D procedures and the physical strain was also comparable to others in terms of ergonomics and weight.

Coherent perfect absorption in one-sided reflectionless media.

In optical experiments one-sided reflectionless (ORL) and coherent perfect absorption (CPA) are unusual scattering properties yet fascinating for their fundamental aspects and for their practical interest. Although these two concepts have so far remained separated from each other, we prove that the two phenomena are indeed strictly connected. We show that a CPA-ORL connection exists between pairs of points lying along lines close to each other in the 3D space-parameters of a realistic lossy atomic photonic crystal. The connection is expected to be a generic feature of wave scattering in non-Hermitian optical media encompassing, as a particular case, wave scattering in parity-time (PT) symmetric media.

From less to maximally invasiveness in cervical spine surgery: A "nightmare" case who deserve consideration.

INTRODUCTION: Multilevel cervical myelopathy without surgical treatment is generally poor in the neurological deficit without surgical decompression. The two main surgical strategies used for the treatment of multilevel cervical myelopathy are anterior decompression via anterior corpectomy or posterior decompression via laminctomy/laminoplasty. PRESENTATION OF CASE: We present the case of a 62 year-old lady, harboring rheumatoid artritis (RA) with gait disturbances, pain, and weakness in both arms. A C5 and C6 somatectomy, C4-C7 discectomy and, instrumentation and fusion with telescopic distractor "piston like", anterior plate and expandable screws were performed. Two days later the patient complained dysfagia, and a cervical X-ray showed hardware dislocation. So a C4 somatectomy, telescopic extension of the construct up to C3 with expandible screws was performed. After one week the patient complained again soft dysfagia. New cervical X-ray showed the pull out of the cranial screws (C3). So the third surgery "one stage combined" an anterior decompression with fusion along with posterior instrumentation, and fusion was performed. DISCUSSION: There is a considerable controversy over which surgical approach will receive the best clinical outcome for the minimum cost in the compressive cervical myelopathy. However, the most important factors in patient selection for a particular procedure are the clinical symptoms and the radiographic alignment of the spine. the goals of surgery for cervical multilevel stenosis include the restoration of height, alignment, and stability. CONCLUSION: We stress the importance of a careful patients selection, and invocated still the importance for 360° cervical fixation.

Non-Hermitian degeneracies and unidirectional reflectionless atomic lattices.

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.