Montgomery Salivary Bypass Tube vs Self-Expandable Metal Stents for the treatment of esophageal strictures after total laryngectomy: a crossover study.

Objectives: Dysphagia affects 16% of patients undergoing total laryngectomy; of these, a third is due to pharyngoesophageal stenosis. Currently, the treatment is cyclic dilation of the stricture and Montgomery Salivary Bypass Tube (MSBT) application. The aim of this study is to assess whether using Self-Expandable Metal Stent (SEMS) may give better results after a non-durable response to repeated dilatation and application of MSBT. Materials and Methods: We verified whether using SEMS after at least 3 cyclic dilations and application of MSBT results in a longer dysphagia-free time in laryngectomized patients with pharyngolesopha-geal stenosis. Secondary outcomes were the duration of the procedures, radiation exposure and complications. Results: We enrolled 6 patients with a median age of 65 years (QR 62.5 - 75.75), of which 50% had undergone radiotherapy. Friedman's test for the duration of the dysphagia-free period did not show a statistically significant difference between the two groups (Friedman chi-squared = 2.6667, df = 1, p-value = 0.1025). The time required to implant the MSBT was significantly less than that required to implant the SEMS (Friedman chi-squared = 6, df = 1, p-value = 0.01431). Radiation exposure was absent for MSBT, while SEMS implant required an exposure to X-rays during the procedure and after 48 hours for placement verification. Two patients experienced short-term complications after SEMS implantation and one after two weeks from MSBT implantation; none of them had any health consequences. Conclusion: In patients who are already undergoing cyclic dilations and application of MSBT, switching to SEMS is not beneficial. Furthermore, MSBT has a significantly shorter implant procedure, does not expose the patient to X-rays, and, in the absence of complications, has a longer duration before removal.

Effects of COVID-19 pandemic on head and neck oncology activity: the experience of our University Hospital.

OBJECTIVE: The COVID-19 pandemic has severely affected otolaryngology and head and neck activities, also involving diagnosis and treatment of patients with oncology diseases with consequent delays and tumor upstaging. The aim of this study was to describe the experience of our otolaryngology unit during the pandemic on patients with cancer of the head and neck, comparing data on anatomical site of origin and preferred treatment with pre-pandemic data. PATIENTS AND METHODS: This study retrospectively analyzed the clinical records of patients treated for oncology disorders of the head and neck in the Otolaryngology Unit of the Policlinico Umberto I, Sapienza University of Rome, between March 10, 2020, and March 9, 2021. Data were compared with the same period of the previous year (March 10, 2019 - March 9, 2020). RESULTS: During the pandemic, we treated 92 patients with malignant tumor of the head and neck, compared to 101 patients treated during the same period of 2019 (-8.91%). The most common anatomical sites of origin of the neoplasms were larynx, oral cavity, and oropharynx. Surgical approach was preferred in 57 patients (61.95%); non-surgical treatments were performed in 35 cases (38.05%). Compared to the same period of the previous year, we found a 12.90% decrease in the number of oncology patients undergoing surgery, while patients treated exclusively with non-surgical approaches increased by 18.42%. CONCLUSIONS: Despite the impact of COVID-19 on the activity of our otolaryngology unit and on the whole healthcare system, diagnostic and therapeutic procedures for patients affected by malignancy of head and neck region were only minimally impacted.

Evaluating very high energy electron RBE from nanodosimetric pBR322 plasmid DNA damage.

This paper presents the first plasmid DNA irradiations carried out with Very High Energy Electrons (VHEE) over 100-200 MeV at the CLEAR user facility at CERN to determine the Relative Biological Effectiveness (RBE) of VHEE. DNA damage yields were measured in dry and aqueous environments to determine that ~ 99% of total DNA breaks were caused by indirect effects, consistent with other published measurements for protons and photons. Double-Strand Break (DSB) yield was used as the biological endpoint for RBE calculation, with values found to be consistent with established radiotherapy modalities. Similarities in physical damage between VHEE and conventional modalities gives confidence that biological effects of VHEE will also be similar-key for clinical implementation. Damage yields were used as a baseline for track structure simulations of VHEE plasmid irradiation using GEANT4-DNA. Current models for DSB yield have shown reasonable agreement with experimental values. The growing interest in FLASH radiotherapy motivated a study into DSB yield variation with dose rate following VHEE irradiation. No significant variations were observed between conventional and FLASH dose rate irradiations, indicating that no FLASH effect is seen under these conditions.

The challenge of ionisation chamber dosimetry in ultra-short pulsed high dose-rate Very High Energy Electron beams.

High dose-rate radiotherapy, known as FLASH, has been shown to increase the differential response between healthy and tumour tissue. Moreover, Very High Energy Electrons (VHEEs) provide more favourable dose distributions than conventional radiotherapy electron and photon beams. Plane-parallel ionisation chambers are the recommended secondary standard systems for clinical reference dosimetry of electrons, therefore chamber response to these high energy and high dose-per-pulse beams must be well understood. Graphite calorimetry, the UK primary standard, has been employed to measure the dose delivered from a 200 MeV pulsed electron beam. This was compared to the charge measurements of a plane-parallel ionisation chamber to determine the absolute collection efficiency and infer the ion recombination factor. The dose-per-pulse measured by the calorimeter ranged between 0.03 Gy/pulse and 5.26 Gy/pulse, corresponding to collection efficiencies between 97% and 4%, respectively. Multiple recombination models currently available have been compared with experimental results. This work is directly applicable to the development of standard dosimetry protocols for VHEE radiotherapy, FLASH radiotherapy and other high dose-rate modalities. However, the use of secondary standard ionisation chambers for the dosimetry of high dose-per-pulse VHEEs has been shown to require large corrections for charge collection inefficiency.

The role of cytokines in head and neck squamous cell carcinoma: A review.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, accounting for approximately 6% of all cancer cases and responsible for an estimated 1-2% of all cancer deaths. Much research evidence has accumulated in the recent years on the changes in the expression of pro-inflammatory and, to a lesser extent, anti-inflammatory cytokines, that (i) may have a role in the malignant transformation of HNSCC, (ii) may be used as diagnostic markers in the sera of patients because of their excessive production by the tumor cells and (iii) may act as possible immunotherapeutic targets. Among pro-inflammatory cytokines, interleukin-8 (IL--8) has been reported to have an important role in cancer invasion, angiogenesis and metastasis. Recent studies have shown an increased concentration of IL--8 in patients with HNSCC and a positive association with lymph node metastasis and tumor classification, although IL--8 was not significantly associated with shorter overall survival and cancer progression-free survival. Additional evidence on the pathological mechanism of origin, invasion, and metastasis of HNSCC, as well as a better understanding of the implications of cytokines, chemokines and growth factors, are of paramount importance for the advancement of research in head and neck oncology.

High-Throughput Fluorescence Polarization Assay to Identify Ligands Using Purified G Protein-Coupled Receptor.

The development of cell-free high-throughput (HT) methods to screen and select novel lead compounds remains one of the key challenges in G protein-coupled receptor (GPCR) drug discovery. Mutational approaches have allowed the stabilization of GPCRs in a purified and ligand-free state. The increased intramolecular stability overcomes two major drawbacks for usage in in vitro screening, the low receptor density on cells and the low stability in micelles. Here, an HT fluorescence polarization (FP) assay for the neurotensin receptor type 1 (NTS1) was developed. The assay operates in a 384-well format and is tolerant to DMSO. From a library screen of 1272 compounds, 12 (~1%) were identified as primary hits. These compounds were validated in orthogonal assay formats using surface plasmon resonance (SPR), which confirmed binding of seven compounds (0.6%). One of these compounds showed a clear preference for the orthosteric binding pocket with submicromolar affinity. A second compound revealed binding at a nonorthosteric binding region and showed specific biological activity on NTS1-expressing cells. A search of analogs led to further enhancement of affinity, but at the expense of activity. The identification of GPCR ligands in a cell-free assay should allow the expansion of GPCR pharmaceuticals with antagonistic or agonistic activity.

Biophysical characterization of E. coli TolC interaction with the known blocker hexaamminecobalt.

BACKGROUND: The tripartite efflux pump AcrAB-TolC in E. coli is involved in drug resistance by transporting antibiotics out of the cell. The outer membrane protein TolC can be blocked by various cations, including hexaamminecobalt, thereby TolC represents a potential target for reducing antimicrobial resistance as its blockage may improve efficacy of antibiotics. METHODS: We utilized single channel electrophysiology measurements for studying TolC conductance in the absence and presence of the known TolC blocker hexaamminecobalt. Association and dissociation constants of hexaamminecobalt were determined using surface plasmon resonance measurements. Minimum inhibitory concentration (MIC) assays in the absence and presence of antibiotics were carried out for investigating the antibacterial effect of hexaamminecobalt and its potential to reduce MICs. RESULTS: TolC gating in the absence of any ligand is voltage dependent and asymmetric at high applied voltages. Hexaamminecobalt binds to TolC with high affinity and kinetic data revealed fast association and dissociation rates. Despite potent binding to TolC, hexaamminecobalt does not possess an intrinsic antimicrobial activity against E. coli nor does it reduce MIC values of antibiotics erythromycin and fusidic acid. CONCLUSIONS: TolC opening can be effectively blocked by small molecules. More potent channel blockers are needed in order to investigate the eligibility of TolC as drug target. GENERAL SIGNIFICANCE: TolC, a potentially interesting pharmaceutical target can be addressed by small molecules, blocking the channel. Biophysical characterization of the binding processes will support future identification and optimisation of more potent TolC blockers in order to validate TolC as a pharmaceutical target.

Balance and walking involvement in facioscapulohumeral dystrophy: a pilot study on the effects of custom lower limb orthoses.

BACKGROUND: Autosomal dominant facioscapulohumeral dystrophy (FSHD), the third most common muscular dystrophy, is characterised by asymmetric and highly variable muscle weakness. In FSHD patients, the coupling of the ankle muscles impairment with the knee, hip and abdominal muscles impairment, causes complex alterations of balance and walking with deterioration of quality of life (QoL). AIM: The aim of this pilot study is to evaluate the effects of custom orthoses (foot orthosis-FO and ankle foot orthosis-AFO) on balance, walking and QoL of FSHD patients through a multidimensional approach. DESIGN: Pilot study. SETTING: Outpatient Rehabilitation Department of Don Gnocchi Foundation. POPULATION: Fifteen patients with facioscapulohumeral muscular dystrophy were studied. METHODS: On 15 FSHD patients clinical evaluation (Manual Muscle Test-MMT, Clinical Severity Score), performance tests (10 meter Walking test-10mWT and 2 minute Walking Test-2minWT), instrumental assessment (stabilometric evaluation), disability (Rivermead Mobility Index- RMI, Berg Balance Scale-BBS) and patient-oriented (Medical Outcome Study 36-item Short Form-SF-36, North American Spine Society-NASS and Visual Analogue Scale-VAS) measures were performed. Patients were evaluated first, wearing their shoes and then wearing their shoes plus orthoses. This evaluation was performed 1 month after wearing the orthoses. RESULTS: The shoes plus orthoses evaluation, performed after one month in which the patients daily wore the custom lower limb orthoses, showed a significant improvement of walking performance (10-mWT p<0.01), balance (Romberg Index p<0.05; Medio-Lateral Velocity p<0.05) and QoL (PCS p<0.01). CONCLUSION: This pilot study shows that in FSHD patients' custom lower limb orthoses (foot-orthoses and ankle-foot-orthoses); evaluated by using a multidimensional approach, improve walking, balance and QoL. CLINICAL REHABILITATION IMPACT: These preliminary results suggest that custom lower limb orthoses could reduce the risk of falling with a positive effect on our patients' safety. Our results should encourage the scientific community to do efficacy study on this hot topic.

Balance and walking in facioscapulohumeral muscular dystrophy: multiperspective assessment.

BACKGROUND: In the Facioscapulohumeral muscular dystrophy (FSHD), the association of ankle muscle impairment with knee, hip and abdominal weakness causes complex alterations of static (postural) and dynamic (walking) balance, increasing the risk of recurrent falls. Stereophotogrammetric system and body-worn gyroscopes were used to focus on locomotor capacity and upper body movements in FSHD patients respectively. No data have been reported about static balance (plantar pressure and stabilometric parameters) and dynamic balance (spatio-temporal parameters during walking) in patients with FSHD. Moreover it is not known if the balance involvement influences disability and quality of life (QoL) of these patients. AIM: The aim of this study is to quantitatively assess static and dynamic balance in FSHD patients and their influence on disability and QoL. DESIGN: Case control-study. SETTING: Outpatient Rehabilitation Department. POPULATION: Sixteen FSHD patients were compared with 16 matched healthy subjects. METHODS: A baropodometric platform was used to measure plantar pressure and centre of pressure in stance (static evaluation), and spatio-temporal parameters during walking (dynamic evaluation). These quantitative results in FSHD patients were also correlated with validated clinical (Clinical Severity Scale), performance (10m and 2 min Walking Test), disability (Berg Balance Scale, Rivermead Mobility Index) and quality of life (QoL) measures (SF-36, NASS). RESULTS: The patients moved the plantar pressure forward from hindfoot to forefoot. Static balance was significantly reduced in patients compared with healthy subjects. Dynamic evaluation of walking showed a significant reduction of velocity and step length in the patients, and a significant increase in step width. Dynamic and static parameters were significantly related to a reduction of 10 mWT performance while only dynamic parameters were strongly related to disability and QoL. CONCLUSION: FSHD patients present an abnormal static and dynamic balance and they show compensation strategies to avoid falling . The involvement of the dynamic balance worsens the physical aspects of QoL and induces disability. The involvement of static balance induces a reduction of the performance in brief distances. CLINICAL REHABILITATION IMPACT: The balance training should be considered in the rehabilitation program of FSHD patients; the compensation strategies adopted by these patients should be considered in the ankle foot orthosis treatment. The static and dynamic balance assessment in FSHD patients can be used in natural history studies.