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1.
Acta Crystallogr D Struct Biol ; 79(Pt 10): 944-952, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37747292

RESUMO

Over the past two decades, serial X-ray crystallography has enabled the structure determination of a wide range of proteins. With the advent of X-ray free-electron lasers (XFELs), ever-smaller crystals have yielded high-resolution diffraction and structure determination. A crucial need to continue advancement is the efficient delivery of fragile and micrometre-sized crystals to the X-ray beam intersection. This paper presents an improved design of an all-polymer microfluidic `chip' for room-temperature fixed-target serial crystallography that can be tailored to broadly meet the needs of users at either synchrotron or XFEL light sources. The chips are designed to be customized around different types of crystals and offer users a friendly, quick, convenient, ultra-low-cost and robust sample-delivery platform. Compared with the previous iteration of the chip [Gilbile et al. (2021), Lab Chip, 21, 4831-4845], the new design eliminates cleanroom fabrication. It has a larger imaging area to volume, while maintaining crystal hydration stability for both in situ crystallization or direct crystal slurry loading. Crystals of two model proteins, lysozyme and thaumatin, were used to validate the effectiveness of the design at both synchrotron (lysozyme and thaumatin) and XFEL (lysozyme only) facilities, yielding complete data sets with resolutions of 1.42, 1.48 and 1.70 Å, respectively. Overall, the improved chip design, ease of fabrication and high modifiability create a powerful, all-around sample-delivery tool that structural biologists can quickly adopt, especially in cases of limited sample volume and small, fragile crystals.


Assuntos
Cicloparafinas , Muramidase , Cristalografia , Muramidase/química , Microfluídica/métodos , Temperatura , Desenho de Equipamento , Cristalografia por Raios X , Proteínas , Polímeros
2.
Opt Express ; 31(8): 12717-12724, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157427

RESUMO

We demonstrate ultra-broadband spectral combining of ultrashort pulses from Yb-doped fiber amplifiers, with coherently spectrally synthesized pulse shaping, to achieve tens-of-fs pulses. This method can fully compensate for gain narrowing and high order dispersion over broad bandwidth. We produce 42fs pulses by spectrally synthesizing three chirped-pulse fiber amplifiers and two programmable pulse shapers across an 80nm overall bandwidth. To the best of our knowledge, this is the shortest pulse duration achieved from a spectrally combined fiber system at one-micron wavelength. This work provides a path toward high-energy, tens-of-fs fiber chirped-pulse amplification systems.

3.
Ear Nose Throat J ; 102(9): NP436-NP439, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34074156

RESUMO

Perineurioma (PN) is an uncommon benign peripheral nerve sheath tumor. For the rarity of this tumor in the oral cavity, otolaryngologists and oral surgeons might not be familiar with this entity. Perineuriomas are typically benign and complete excision is deemed adequate management. Thus, their histological recognition is mandatory to avoid unnecessary overtreatment. We report the clinicopathologic findings of an uncommon variant, the Extraneural Sclerosing PN, in an unusual and never described site, the tongue.


Assuntos
Neoplasias dos Nervos Cranianos , Neoplasias de Bainha Neural , Humanos , Língua/patologia , Boca/patologia , Neoplasias de Bainha Neural/diagnóstico , Neoplasias de Bainha Neural/cirurgia , Neoplasias de Bainha Neural/patologia
4.
Ear Nose Throat J ; 102(1): NP46-NP48, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33459562

RESUMO

Schwannomas are neurogenic benign tumors originating from the myelin sheath of peripheral nerves, and hypoglossal Schwannomas account for 5% of nonvestibular ones. Extracranial localizations are substantially rare, especially those affecting exclusively the parapharyngeal space; for this reason, the retrostyloid neoformations could initially masquerade as a carotid tumor or deep organized neck abscess. The purpose of this report is to highlight the importance of a multidisciplinary approach in the correct management of differential diagnosis.


Assuntos
Nervo Hipoglosso , Espaço Parafaríngeo , Humanos , Abscesso/diagnóstico por imagem
5.
Ear Nose Throat J ; 102(5): NP220-NP222, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-33764199

RESUMO

Salivary Bypass Tube is an important tool to prevent or treat some complications of laryngeal and hypopharyngeal surgery and its placement may prove difficult. In this article, we propose a new technique to simplify its management by using an Oral/Nasal Tracheal Tube Cuffed-Reinforced that allowed us to reduce operating times, complications related to prolonged general anesthesia, and the traumas on the tissues incurred during the forced positioning of the device with standard techniques.


Assuntos
Fístula Traqueoesofágica , Humanos , Fístula Traqueoesofágica/etiologia , Fístula Traqueoesofágica/cirurgia , Constrição Patológica/etiologia , Hipofaringe/cirurgia
6.
Sensors (Basel) ; 22(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36366057

RESUMO

Rotating-coil measurement systems are widely used to measure the multipolar fields of particle accelerator magnets. This paper presents a rotating-coil measurement system that aims at providing a complete data set for the characterization of quadrupole magnets with small bore diameters (26 mm). The PCB magnetometer design represents a challenging goal for this type of transducer. It is characterized by an aspect ratio 30% higher than the state of the art, imposed by the reduced dimension of the external radius of the rotating shaft and the necessity of covering the entire magnet effective length (500 mm or higher). The system design required a novel design for the mechanical asset, also considering the innovation represented by the commercial carbon fiber tube, housing the PCB magnetometer. Moreover, the measurement system is based primarily on standard and commercially available components, with simplified control and post-processing software applications. The system and its components are cross-calibrated using a stretched-wire system and another rotating-coil system. The measurement precision is established in a measurement campaign performed on a quadrupole magnet characterized by an inner bore diameter of 45 mm.

7.
Cancers (Basel) ; 14(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36230786

RESUMO

The aim of this study was to systematically review the literature of sarcoma of the parotid gland in order to analyze the main factors affecting survival rate. A systematic literature review was performed between January 1990 to November 2021, and 88 patients affected by parotid gland sarcomas were included. The most common histological types were Rhabdomyosarcoma and Synovial Sarcoma. From our review, it emerges that primary sarcomas of the parotid glands are locally aggressive but show low tendency to metastasize to the lymph nodes of the neck and that surgery (i.e., total or radical parotidectomy) is the main approach for their treatment. The global overall survival (OS) is 52% at 5 years and 34.1% at 10 years. The OS for T1, T2, T3, T4 tumor at 5 years of follow up is 80.0%, 66.5%, 56.7% and 33.3%, respectively. Size/extension at the diagnosis and the sarcoma's histotype are the most important prognostic factors. Multivariate analysis showed that surgery (total or radical parotidectomy) performed on the tumor (p = 0.0008) was the only parameter that significantly affected the OS. Among the other variables, age (younger), use of adjuvant therapy and lymph node metastasis showed borderline significative values (p = 0.05). Our analysis suggests that, when a primitive parotid sarcoma is diagnosed, total or radical parotidectomy should be performed at any age independent of tumor histology. Because regional lymph node metastases from parotid sarcomas are uncommon, alternative strategies (e.g., close follow-up by imaging and evaluation of sentinel lymph nodes) should be pursued before lymph node (selective/radical) dissection.

8.
Ear Nose Throat J ; : 1455613221115119, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36125267

RESUMO

Attempts to analyze clinical unexpected cases of laryngeal fractures based on mild symptoms and physical findings. Even though a laryngeal fracture is rare in a living patient and when happens it is related to severe airways emergency, this case reported seems important to offer a possible differential diagnosis in patients who present with the same symptoms, if no other causes have been detected, like another one benign laryngeal disease.

9.
Sci Prog ; 105(3): 368504221110854, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35866218

RESUMO

Attempts to analyze respiratory function of the laryngectomized patient with tests such as spirometry and plethysmography have been described in the literature, highlighting however substantial difficulties. Oscillometry, through the forced oscillation technique (FOT), measures the mechanical properties of the respiratory system minimizing the problems related to the patient's lack of compliance. This methodology has never been applied to these patients and therefore represents a new perspective in the analysis of respiratory function.


Assuntos
Resistência das Vias Respiratórias , Doença Pulmonar Obstrutiva Crônica , Humanos , Oscilometria/métodos , Testes de Função Respiratória/métodos , Espirometria/métodos
10.
Opt Express ; 30(8): 12639-12653, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472897

RESUMO

An 8-beam, diffractive coherent beam combiner is phase controlled by a learning algorithm trained while optical phases drift, using a differential mapping technique. Combined output power is stable to 0.4% with 95% of theoretical maximum efficiency, limited by the diffractive element.

11.
Clin Case Rep ; 10(1): e05300, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35079396

RESUMO

Hemangiomas are developmental vascular abnormalities that are common in the head and neck (60%), rare in the oral cavity, and uncommon in the tongue. A patient performed a multi-parametric MRI, which characterized the lesion of his tongue, providing relevant information for diagnostic, therapeutic orientation, and realization of slight aggressive surgery with consequent excellent recovery.

12.
Eur Arch Otorhinolaryngol ; 279(3): 1167-1173, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34351467

RESUMO

PURPOSE: Carcinosarcoma, also known as Spindle Cell Carcinoma (SpCC), is a rare type of malignant tumor. Generally, this type of pathology occurs in the urogenital tract, the gastrointestinal tract, respiratory tract and mammary gland; in the larynx, SpCC represents only 2-3% of all malignancies. Due to its rarity, there is currently no generally acceptable treatment guideline for this disease. The aim of this study was to systematically review the literature of SpCC of larynx and report epidemiologic, clinicopathologic and main therapeutic approaches for this entity. METHODS: A systematic literature review was performed using MEDLINE, EMBASE, PubMed and Scopus databases. For this review, the results were extrapolated in the period between January 1990 to September 2020. Data extraction was performed using a standard registry database. The clinical and pathological staging were recalculated according to the Eight Edition of AJCC Cancer Staging Manual and statistical analyses were performed using SPSS Version 25.0. RESULTS: A total of 111 patients affected by laryngeal carcinosarcoma were included. From our review arises that surgery is the main treatment for primary laryngeal carcinosarcoma. In this way, various techniques such as minimally invasive laryngoscopy excision, laser CO2 cordectomy, partial laryngectomy (vertical and horizontal) and total laryngectomy. The role of radiotherapy is still controversial. The overall survival (OS) for T1 stage tumor at 5 years of follow-up is 82.9%, the OS for T2 and T3 tumor is 74% and 73.4%. The OS at 5 years of follow-up is 91.7% for supraglottic tumor, 69.3% for glottic tumor and 50% for transglottic site. Subglottic site is described in only 2 cases [12-13], so the OS at 5 years is not statistically significant. The 5-year overall survival in patients without lymph nodes involvement (N0) is 90.2%, 66.7% and 50%, respectively, for N1 and N2 lesions. CONCLUSION: Primary laryngeal carcinosarcoma is a very rare malignancy. There are no clear guidelines in the management but in the literature, surgery is described as the best modality of therapy; radiation only can be a reasonable alternative with controversial efficacy. The most important prognostic factor is the nodal metastasis.


Assuntos
Carcinossarcoma , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Laringe , Carcinossarcoma/diagnóstico , Carcinossarcoma/cirurgia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Laringectomia/métodos , Laringe/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos
13.
Head Neck Pathol ; 15(4): 1308-1312, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33394373

RESUMO

Carcinoma cuniculatum (CC) is a rare clinicopathologic variant of squamous cell carcinoma. Histologically, it is characterized by invasive growth of bland, acanthotic, and keratinizing squamous epithelium that forms multiple rabbit burrow-like, keratin-filled crypts and sinuses. We present a 51-year-old male smoker with CC of the left vocal cord. The tumor was staged T1a and the patient was disease-free 12 months after surgery. To our knowledge, this is the fourth case of CC of the larynx reported in the English literature and the first, due to its early diagnosis, where radical surgery was not performed. We highlight the necessity for awareness of this entity and coordination between otolaryngologists, radiologists, and pathologists for early diagnosis and organ-sparing surgical treatment.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Laríngeas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Laringoscopia , Masculino , Pessoa de Meia-Idade , Fumantes , Tomografia Computadorizada por Raios X
14.
Artigo em Inglês | MEDLINE | ID: mdl-33276507

RESUMO

Occupational noise exposure accounts for approximately 16% of all disabling hearing losses, but the true value and societal costs may be grossly underestimated because current regulations only identify hearing impairments in the workplace if exposures result in audiometric threshold shifts within a limited frequency region. Research over the past several decades indicates that occupational noise exposures can cause other serious auditory deficits such as tinnitus, hyperacusis, extended high-frequency hearing loss, and poor speech perception in noise. Beyond the audiogram, there is growing awareness that hearing loss is a significant risk factor for other debilitating and potentially life-threatening disorders such as cardiovascular disease and dementia. This review discusses some of the shortcomings and limitations of current noise regulations in the United States and Europe.


Assuntos
Ruído Ocupacional/efeitos adversos , Limiar Auditivo , Europa (Continente) , Audição , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/epidemiologia , Perda Auditiva Provocada por Ruído/etiologia , Humanos
15.
Sci Rep ; 10(1): 11457, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651403

RESUMO

A method to monitor the length of a particle bunch, based on the combination of a Radio Frequency Deflector (RFD) with magnetic focusing elements, is presented. With respect to state-of-the-art bunch length measurement, the additional focusing element allows to measure also the correlations between the longitudinal and transverse planes in terms of both position and divergence. Furthermore, the quadrupole-based focusing increases the input dynamic range of the measurement system (i.e.  allows for a larger range of beam Twiss parameters at the entrance of the RFD). Thus, measurement resolution and precision are enhanced, by simultaneously preserving the accuracy. In this paper, the method is first introduced analytically, and then validated in simulation, by the reference tool ELEctron Generation ANd Tracking, ELEGANT. Finally, a preliminary experimental validation at CLEAR (CERN Linear Electron Accelerator for Research) is reported.

16.
Biomed Phys Eng Express ; 7(1)2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34037536

RESUMO

The aim of this work is the dosimetric characterization of a plane parallel ionization chamber under defined beam setups at the CERN Linear Electron Accelerator for Research (CLEAR). A laser driven electron beam with energy of 200 MeV at two different field sizes of approximately 3.5 mm FWHM and approximately 7 mm FWHM were used at different pulse structures. Thereby the dose-per-pulse range varied between approximately 0.2 and 12 Gy per pulse. This range represents approximately conventional dose rate range beam conditions up to ultra-high dose rate (UHDR) beam conditions. The experiment was based on a water phantom which was integrated into the horizontal beamline and radiochromic films and an Advanced Markus ionization chamber was positioned in the water phantom. In addition, the experimental setup were modelled in the Monte Carlo simulation environment FLUKA. In a first step the radiochromic film measurements were used to verify the beamline setup. Depth dose distributions and dose profiles measured by radiochromic film were compared with Monte Carlo simulations to verify the experimental conditions. Second, the radiochromic films were used for reference dosimetry to characterize the ionization chamber. In particular, polarity effects and the ion collection efficiency of the ionization chamber were investigated for both field sizes and the complete dose rate range. As a result of the study, significant polarity effects and recombination loss of the ionization chamber were shown and characterized. However, the work shows that the behavior of the ionization chamber at the laser driven beam line at the CLEAR facility is comparable to classical high dose-per-pulse electron beams. This allows the use of ionization chambers on the CLEAR system and thus enables active dose measurement during the experiment. Compared to passive dose measurement with film, this is an important step forward in the experimental equipment of the facility.


Assuntos
Elétrons , Radiometria , Método de Monte Carlo , Aceleradores de Partículas , Água
17.
Int Tinnitus J ; 23(2): 79-85, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32009339

RESUMO

Many studies have focused on the relationship between hearing loss and Alzheimer's Disease (AD). The mechanisms and causal relationship of this association are still partially unknown, and several theories have been proposed. The most accredited hypothesis is that peripheral hearing deprivation may lead to social isolation and subsequently to dementia. Another hypothesis supports the role of hearing loss on cortical processing, with an increased assignment of cognitive resources to auditory processing rather than to other cognitive processes; other theories suggest changes in the brain structure following reduced peripheral auditory stimulation, or a common cause to both conditions. These preliminary findings clearly delineate the importance of further research aimed at investigating hearing impairment in AD, to a) allow early detection of people with predisposition to AD, b) improve the quality of life in AD patients with hearing loss and c) possibly prevent the progression of the disease treating the hearing impairment. In this review paper, the authors discuss current evidence on the association between hearing impairment and dementia, the identification of peripheral and central auditory dysfunction in at-risk patients as a potential early indicator of incipient AD, and the clinical aspects and the management of patients with AD and hearing loss.


Assuntos
Doença de Alzheimer/complicações , Perda Auditiva/etiologia , Humanos
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