Functional outcomes after transanal total mesorectal excision (TaTME): a random forest analysis to predict patients' outcomes

PURPOSE

Anorectal, sexual, and urinary dysfunction are common issues after rectal cancer surgery, although seldom explored. The primary aim of this study was to investigate postoperative anorectal functional results.

METHODS

Patients with mid/low-rectal cancer treated with transanal TME (TaTME) with primary anastomosis with/without diverting stoma between 2015 and 2020 were reviewed and selected if they had a minimum follow-up of 6 months (from the primary procedure or stoma reversal). Patients were interviewed using validated questionnaires and the primary outcome was bowel function based on Low Anterior Resection Syndrome (LARS) scores. Statistical analyses were performed to identify clinical/operative variables correlated with worse outcomes. A random forest (RF) algorithm was computed to classify patients at a greater risk of minor/major LARS.

RESULTS

Ninety-seven patients were selected out of 154 TaTME performed. Overall, 88.7% of the patients had a protective stoma and 25.8% reported major LARS at mean follow-up of 19.0 months. Statistical analyses documented that age, operative time, and interval to stoma reversal correlated with LARS outcomes. The RF analysis disclosed worse LARS symptoms in patients with longer operative time (> 295 min) and stoma reversal interval (> 5.6 months). If the interval ranged between 3 and 5.6 months, older patients (> 65 years) reported worse outcomes. Finally, no statistical difference was documented when comparing the rate of minor/major LARS in the first 27 cases versus others.

CONCLUSION

One-quarter of the patients developed major LARS after TaTME. An algorithm based on clinical/operative variables, such as age, operative time, and time to stoma reversal, was developed to identify categories at risk for LARS symptoms.

The role of open innovation in fostering SMEs’ business model innovation during the COVID-19 pandemic

Purpose

The economic crisis triggered by the COVID-19 pandemic has had significant consequences on the activities of companies worldwide. This study aims to unveil how open innovation fostered business model innovation in small and medium enterprises (SMEs) during the pandemic.

Design/methodology/approach

The research adopts a qualitative approach, involving a multiple case study methodology, and focusses on six SMEs operating in various traditional sectors.

Findings

The findings highlight the impact of the external stimulus, COVID-19, on business model innovation and the key role of open innovation management in pursuing the business model innovation, which may also involve a digital transformation.

Originality/value

While some studies have examined how the pandemic has fostered business model transformation, to the best of the authors’ knowledge, this is the first study analysing the pivotal role of open innovation in driving business model innovation during challenging times, such as the COVID-19 pandemic.

Strategic agility, openness and performance: a mixed method comparative analysis of firms operating in developed and emerging markets

This research delineates the relationship between strategic agility and performance, and proposes openness as a requisite means to fostering agility and enhancing performance. Methodologically, the research follows the pragmatist paradigm through a mixed-method research design, incorporating three separate studies. These comprise a CEO-based survey on foreign firms operating in emerging markets, a CEO-based survey on firms operating in developed countries, and CEO interviews, all of which are complimented by auxiliary instruments of secondary data and an expert panel. The research finds that strategic agility is vital for firms’ performance in both developed and developing markets. Moreover, we found that while search depth amplifies the above relationship in both contexts, search breadth does it only in the context of foreign firms operating in emerging markets. The value of these findings stems from their elucidation of the role of strategic agility in emerging markets and its comparison to that of firms operating in developed countries; their insights into strategic agility’s relationship with openness; their schematic culmination into a systemically and contextually depicted framework; and their prescriptive managerial implications.

Short-term electrocardiographic atrial remodelling after asd closure with the gco device in a pediatric population

Funding Acknowledgements

Type of funding sources: None.

Background and Aim

The GORE® CARDIOFORM septal occluder (GCO) is an atrial septal defect/patent foramen ovale (ASD/PFO) closure device with theoretical advantages over other commercialized devices thanks to its softness and anatomical compliance.

Our aim was to evaluate the short and medium-term electrocardiographic changes after percutaneous ASD closure with GCO in a pediatric population.

Methods

We enrolled 39 patients with isolated ASD submitted to trans-catheter closure with GCO from January 2020 to June 2021. EKG was performed before (T0), at 24 hours (T1) and 6 months (T2) after ASD transcatheter closure. P wave dispersion was calculated as the difference between maximum and minimum P- wave duration, PR interval as the interval between beginning of the P wave and beginning of the QRS complex and QT dispersion as the difference between maximun and minimun of QTc intervals. At 6-months from device implantation, the patients were submitted to ambulatory EKG Holter recording.

Results

Patients’ age and BSA were 8.2±4.2 years (IQR 4.2-8.3, median 7.0) and 1.0±0.3 m2 (IQR 0.7-1.7, median 0.9), respectively. The strectched ASD diameter was 16.3±4.5 mm (median 16), resulting in QP/QS of 1.7±0.6 (median 1.5). At the baseline mean P wave dispersion was 40±15 msec and decreased to 30±13 msec (p<0.002) at 24h, without any further change at 6 months (30±13 msec, p<0.002). PR conduction significantly improved at 24 h from device implantation (from 175.0±20.8 to 144.0±22.7 msec, p=0.018) and did not significantly change at 6 months (164.0±19.5 msec, p=NS). QTc dispersion decreased at 24 hours (31.7±.20.3, p<0.02) and at 6 months (28.0±18.1, p<0.002) from device implantation. After device deployment, 2 pts (5%) developed transient, self-limited junctional rhythm and one of them needed a short course of anti-arrhythmic therapy for supra-ventricular tachycardia. No tachy/brady-arrhythmias were recorded at the 6-months follow-up EKG Holter monitoring.

Conclusions

Percutaneous ASD closure with the GCO device results in significant, sudden improvement of intra-atrial, atrio-ventricular and intraventricular electrical homogeneity. This benefit persists unaltered over a medium term follow-up. It might be due to a favourable volumetric remodelling that was not hindered by mechanical impact of the occluding prosthesis and could explain the low rate of arrhythmias found at the mid-term EKG evaluation.

C36 ATRIAL SEPTAL DEFECT CLOSURE WITH A NEW OCCLUDER DEVICE, EXPERIENCE ON 100 PATIENTS

Background

This perspective, observational study evaluated safety and efficacy of the GORE® Cardioform ASD Occluder (WL Gore & Associates, Flagstaff, AZ), compliant and potentially innovative prosthesis recently approved for closure of ostium secundum atrial septal defects (ASD).

Methods

100 unselected patients with significant ASD were submitted to trans–catheter closure with GORE® Cardioform ASD Occluder at two high–volume Italian Pediatric Cardiology centers. Primary endpoints were procedural success and safety. Secondary endpoints were closure rate and clinical safety at 1–month and 6–month follow–up.

Results

Patients‘age and weight were 7.8 (6.0–13.6)and 26.1 (20.0–54.0), respectively. ASD diameter was 17.4 + 4.4, resulting in QP/QS of 1.7 ± 0.7 (median 1.6). 33 patients presented an asd larger than 18mm in diameter. 58% of defects were considered complex based on the following characteristics: deficient rim(s) (except aortic rim), aneurismal/multi–fenestrated and ASD size/pt weight ratio >1.2. Device placement was successfully achieved in all but two patients (98%), in whom it embolized early after deployment, resulting in rescue surgical repair. No cross–over with different devices was recorded. Median procedure and fluoroscopy times were 54 and 11 min, respectively. Major adverse events were recorded in 7 pts. Complete closure rate was 87.3% at discharge, rising to 95.5% (39/42 pts) at 1 month evaluation, and 100% at 6 months without cardiac or extra–cardiac adverse events. “Complex” procedures were more time–consuming but as effective and safe as the “simple” ones.

Conclusions

The GORE® Cardioform ASD Occluder device was highly effective and versatile in closure of ASDs with different anatomy and size, even in challenging settings.

The impact of organizational ostracism on knowledge hiding: analysing the sequential mediating role of efficacy needs and psychological distress

Purpose

Drawing on the conservation of resources theory and need-threat model, this study aims to analyse the mediating role of efficacy needs (EN) and psychological distress (PD) on the relationship between workplace ostracism (WO) and knowledge hiding (KH) behaviour of employees.

Design/methodology/approach

Time-lagged data were collected from 225 employees working in the mobile telecommunication sector through online survey instruments prepared in light of past literature. SmartPLS3 was used to analyse the data.

Findings

The results obtained confirm the initial hypothesis that there exists a positive relationship between WO and KH. Furthermore, the results also established the sequential mediating roles of EN and PD between WO and KH behaviour of employees.

Originality/value

This study adds to the literature suggesting that WO represents a real threat to companies that aim to foster knowledge-sharing behaviours. Moreover, it reveals that EN and PD are two underlying mechanisms behind the baseline relationship.

Heller myotomy versus Heller myotomy with fundoplication in patients with achalasia: a systematic review and meta-analysis

INTRODUCTION

Heller myotomy (HM) remains the gold standard procedure for achalasia. The addition of different types of fundoplication to HM has been debated in several studies. Given the contradictory reports, this meta-analysis was undertaken to compare different outcomes after HM and HM with fundoplication (HMF).

METHODS

An electronic search was performed among five major databases (PubMed, Ovid, Scopus, Cochrane Library, Google Scholar) from inception to October 2019, identifying all randomised and non-randomised studies comparing HM with HMF. Two authors searched electronic databases using the keywords 'achalasia' AND 'dysphagia' AND 'gastroesophageal reflux' and all data were pooled for random-effects meta-analysis. The primary and secondary outcomes were gastroesophageal reflux and dysphagia, respectively.

RESULTS

A total of six studies were included and involved 576 patients comparing HM and HMF. There was no statistically significant difference between gastroesophageal reflux in the HM vs HMF group (21.3% vs 22.9%, RR 1.32, 95% CI 0.60-2.88, p = 0.49). There was a slightly higher incidence of dysphagia observed in HM vs HMF (14.8% vs 10.8%, RR 1.54, 95% CI 0.98-2.41, p = 0.06).

CONCLUSIONS

There was no statistically significant difference in long-term outcomes between a group of patients undergoing HM and a group who underwent HM with fundoplication.

The adding value of fluid challenge and balloon occlusion tests in patients with atrial septal defect

Background

Careful, step-wise assessment is required in all patients with an atrial septal defect (ASD) to exclude pre-existing pulmonary vascular disease or left ventricular disease. Fluid challenge test (FCT) and balloon occlusion testing (BOT) may unmask left ventricular disease and challenge the pulmonary circulation, but their complementary role in the evaluation of patients with “operable” ASD is not well established.

Aim

To evaluate the haemodynamic changes of the pulmonary circulation by FCT and BOT in ASD patients undergoing percutaneous closure according to the current guidelines.

Methods

Consecutive patients selected for percutaneous ASD closure underwent invasive hemodynamic assessment at baseline and after BOT, FCT and both.

Results

Fifty patients (mean age 47.3±11.7 years, 72% female) were included. All patients had a pulmonary-to-systemic flow ratio (QP/QS) ≥1.5, pulmonary vascular resistance (PVR) <5 WU and pulmonary arterial wedge pressure (PAWP) <15 mmHg. Individuals with a PVR ≥2 WU at baseline were older, more symptomatic, with a higher baseline systemic vascular resistance compared to the lower PVR group (PVR <2 WU; p<0.0001). The response of Qp/Qs to FCT was different between groups (p<0.0001, Figure 1). Patients with a lower baseline PVR experienced an increase in Qp/Qs, which remained above 1.5 in all patients, whereas in almost all (90%) patients with a higher baseline PVR, the Qp/Qs fell to below 1.5.

FCT caused a marked increase in pulmonary blood flow of almost 2 liters (p<0.0001) accompanied by increases in PAWP (p<0.0001). BOT led to a modest increase in PAWP (Δ1.5 [−1.0–7.0] mmHg, p<0.0001). FCT added to BOT caused a further increase in PAWP and Qs (both p<0.0001), while PVR was unchanged (p>0.1).

No difference was observed in the PAWP response to FCT, BOT or both between groups; no patients reached a PAWP ≥18 mmHg following FCT or BOT alone, but 4 (8%) patients did following the addition of FCT to BOT. No acute clinical adverse events were experienced by any patients.

Conclusions

None of the reported ASD patients presented with FCT criteria of post-capillary PH (that is a PAWP >18 mmHg). Even small rises in PVR may have significant implications on cardiovascular haemodynamics. In fact, patients with PVR <2 WU showed an increase in Qp/Qs, which remained above 1.5 in all patients, suggesting that they still had a distensible pulmonary circulation, whereas in almost all patients with a PVR ≥2 WU, the Qp/Qs fell to below 1.5.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Internal and external antecedents of open innovation adoption in IT organisations: insights from an emerging market

Purpose

This study aims to propose and test a theoretical model exploring the impact of internal and external factors of social media use by IT organisations on open innovation (OI) adoption with the mediating effect of knowledge management capabilities.

Design/methodology/approach

Data were collected from 200 IT firms and partial least squares structural equation modelling was used to analyse the data of this study and to test the research hypotheses.

Findings

The results revealed that both customer involvement in social media and top management support (TMS) for social media had a significant impact on OI adoption. However, only the relationship between TMS for social media usage and OI link was mediated by knowledge management capability.

Practical implications

This study stresses the importance of social media policy development for business managers to create an interactive platform for their customers to participate in the activities of the firm. Moreover, the results suggest that for developing open knowledge management capabilities, leaders must focus on and support the use of social media technologies by the firms.

Originality/value

Social media technologies have taken the world by storm. Organisations and individuals are influenced by the knowledge available on Web 2.0 platforms. Most of the current research has focussed on the impact of social media use on OI in developed countries, but developing nations on the Asian continent have been left out of this discussion. Moreover, while most studies have focussed on the OI outcomes, less efforts have been directed towards understanding and exploring the OI antecedents.

Response to fluid challenge in patients with atrial septal defect

Background

A fluid challenge test (FCT) with a rapid infusion of saline allows for discrimination between pre- and post-capillary pulmonary hypertension (PH) and may unmask hidden post-capillary PH. Patients with atrial septal defect (ASD) may develop pre- or post-capillary PH after shunt closure respectively in case of pulmonary vascular disease or left ventricular disease.

Aim

To evaluate the haemodynamic changes of the pulmonary circulation in ASD patients undergoing percutaneous closure with indicated according to the current ESC guidelines.

Methods

Twenty-three patients (mean age 42.9±12.4 years; 15 female) underwent right heart catheterization in basal conditions and after FCT (volume loading with rapid saline infusion of 7 ml/kg in 10 min) before percutaneous closure of the ASD.

Right atrial pressure (RAP), systolic, mean and diastolic pulmonary arterial pressure (sPAP, mPAP and dPAP), pulmonary arterial wedge pressure (PAWP), cardiac output (CO), pulmonary vascular resistance (PVR), systemic vascular resistance (SVR) and the ratio between pulmonary and systemic flow (QP/QS) were calculated four times: before and after inflating the sizing balloon both at baseline and immediately after FCT (Fig. 1).

Results

The patients had an increase in pressures and flows after FCT with open ASD: mPAP (18.7±4.4 vs 16.7±4.6 mmHg, p<0.001), PAWP (11.3±3.1 vs 9.2±3.0 mmHg, p<0.001), QP (12.5±2.3 vs 10.3±2.0 l/min, p<0.001), and QS (6.6±1.4 vs 5.9±1.2 l/min, p<0.001) but RAP remained unchanged (8.7±3.0 vs 8.3±2.4 mmHg, p=0.35). PVR (0.2±0.4 vs 0.8±0.3 Wood Units, p<0.001) and SVR (11.2±3.2 vs 12.5±3.2 Wood Units, p=0.02) decreased, and PVR/SVR (0.06±0.02 vs 0.06±0.3, p=0.25) remained unchanged. QP/QS increased in all patients after FCT (mean±SD: 2.0±0.4 vs 1.8±0.4, p<0.001).

During a temporary ASD closure by sizing balloon, the patients had increases of RAP (9.0±2.6 vs 7.6±2.6 mmHg, p<0.001) mPAP (19.5±4.0 vs 17.4±3.7 mmHg, p<0.001), PAWP (13.2±2.1 vs 11.2±2.9 mmHg, p<0.001), and CO (7.7±2.7 vs 6.8±2.3 l/min, p<0.001) after FCT. PVR remained unchanged (0.9±0.4 vs 1.1±0.6, p=0.12) and SVR reduced (9.8±2.7 vs 11.3±2.9, p<0.001) after FCT.

Conclusions

None of the reported ASD patients presented with FCT criteria of post-capillary PH (that is a PAWP >18 mmHg). The FCT was associated with an increase in QP/QS suggesting that the patients still had a distensible pulmonary circulation. Further studies are needed to explore the relevance of a FCT in ASD patients, particularly those with higher PVR values.

Figure 1

Funding Acknowledgement

Type of funding source: None

Broad band high resolution rotational spectroscopy for Laboratory Astrophysics

We present a new experimental setup devoted to the study of gas phase molecules and processes using broad band high spectral resolution rotational spectroscopy. A reactor chamber has been equipped with radio receivers similar to those used by radio astronomers to search for molecular emission in space. The whole Q (31.5-50 GHz) and W bands (72-116.5 GHz) are available for rotational spectroscopy observations. The receivers are equipped with 16×2.5 GHz Fast Fourier Transform spectrometers with a spectral resolution of 38.14 kHz allowing the simultaneous observation of the complete Q band and one third of the W band. The whole W band can be observed in three settings in which the Q band is always observed. Species such as CH3CN, OCS, and SO2 are detected, together with many of their isotopologues and vibrationally excited states, in very short observing times. The system permits automatic overnight observations and integration times as long as 2.4×105 seconds have been reached. The chamber is equipped with a radiofrequency source to produce cold plasmas and with four ultraviolet lamps to study photochemical processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2, among other species, have been generated and the molecular products easily identified by their rotational spectrum, and mass spectrometry and optical spectroscopy. Finally, the rotational spectrum of the lowest energy conformer of CH3CH2NHCHO (N-Ethylformamide), a molecule previously characterized in microwave rotational spectroscopy, has been measured up to 116.5 GHz allowing the accurate determination of its rotational and distortion constants and its search in space.

How can health professionals contribute to the internet of things body of knowledge

Purpose

Internet of Things (IoT) as the new technological paradigm has found many applications in different domains. Nowadays, more than 30,000 records related to IoT research can be accessed in Scopus (Scopus.com). Health care is the one of domains which benefits from IoT. However, observations indicate that most active researchers in this area are technical people not health professionals. The purpose of this paper is to understand how health professionals can contribute to the IoT body of knowledge.

Design/methodology/approach

IoT professionals are asked to provide their views regarding research concerns, and the collected data are analyzed by phenomenography research methodology.

Findings

Findings indicate that health professionals can contribute through providing information, requirement or standards for developing IoT systems or devices. They can also introduce new applications or domains for which IoT is fit.

Originality/value

This paper tries to fill the gap concerning the lack of attention to undertaking IoT-related research from health professionals’ side and highlights ways that health professionals can contribute IoT body of knowledge.

The Risk of Breast Cancer Subsequent to Histologic Diagnosis of Benign Intraductal Papilloma Follow-Up Study of 339 Cases

The risk of developing breast cancer was investigated in 339 patients in whom histologically confirmed intraductal papilloma had been surgically removed. Follow-up ranged from 2 to 14 years, (average, 6.62 years). Ten breast cancers were observed, whereas 3 were expected on the basis of age-specific incidence rates drawn from local cancer registries (relative risk = 3.33, 95% confidence interval = 1.60-6.13). No significant difference in the relative risk was observed as far as papilloma type (single or multiple) was concerned. All breast cancers observed occurred in the same breast as the papilloma. Women in whom a benign intraductal papilloma has been excised should be carefully followed since they at are higher risk for ipsilateral breast cancer.

Knowledge exploration and ICT knowledge exploitation through human resource management

Purpose

The purpose of the study is to assess the relationships among human resource management (HRM), information and communication technology (ICT), knowledge exploitation and knowledge exploration.

Design/methodology/approach

To reach the study’s goal, The authors applied a quantitative methodology involving ordinary least squares on a sample of 129 Italian firms.

Findings

Results confirm a direct and significant effect of HRM practices on knowledge exploration and a moderation effect of ICT knowledge exploitation on the relationship between HRM practices and knowledge exploration.

Originality/value

The relationship between knowledge management (KM) and HRM is relevant given that HRM can affect organizational culture and the management of strategic knowledge within firms, which is a primary resource to achieve better positioning in the markets. Nevertheless, the implicit link between KM and HRM has been theoretically suggested, but it requires further exploration, in particular through quantitative analysis.

Pyrazinamide susceptibility testing: proposed new standard with the BACTECTM MGITTM 960 system

The susceptibility of 253 Mycobacterium tuberculosis complex isolates to pyrazinamide (PZA) was assessed using the BACTECTM MGITTM 960 (M960) system. Resistant strains underwent paired repeat testing using 1) a critical concentration of 200 g/ml (PZA-200), and 2) a reduced inoculum of 0.25 ml. They were also examined using the BACTEC 460 (B460) reference method and investigated for pncA mutations. On M960, 37 isolates were resistant. In the PZA-200 assay, 20 of these were resistant and 17 susceptible, while 18 were resistant and 19 susceptible with reduced inoculum. The B460 assay and pncA sequencing confirmed results with reduced inoculum.

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactors and the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40 cm long gas cell placed in the beam path of the Aries 40 m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH₃OH, CH₃CH₂OH, HCOOH, OCS, CS, SO₂ (<10^-3 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O₂ and CS₂ was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.

High-quality PVD graphene growth by fullerene decomposition on Cu foils

We present a new protocol to grow large-area, high-quality single-layer graphene on Cu foils at relatively low temperatures. We use C₆₀ molecules evaporated in ultra high vacuum conditions as carbon source. This clean environment results in a strong reduction of oxygen-containing groups as depicted by X-ray photoelectron spectroscopy (XPS). Unzipping of C₆₀ is thermally promoted by annealing the substrate at 800ºC during evaporation. The graphene layer extends over areas larger than the Cu crystallite size, although it is changing its orientation with respect to the surface in the wrinkles and grain boundaries, producing a modulated ring in the low energy electron diffraction (LEED) pattern. This protocol is a self-limiting process leading exclusively to one single graphene layer. Raman spectroscopy confirms the high quality of the grown graphene. This layer exhibits an unperturbed Dirac-cone with a clear n-doping of 0.77 eV, which is caused by the interaction between graphene and substrate. Density functional theory (DFT) calculations show that this interaction can be induced by a coupling between graphene and substrate at specific points of the structure leading to a local sp³ configuration, which also contribute to the D-band in the Raman spectra.

Evaluation of Symptoms and Prevention of Cancer in Menopause: The Value of Vulvar Exam

Vulvar and vaginal atrophy (VVA), is a chronic medical condition experienced by postmenopausal women, with prevalence estimated ranging from 10% to 50% [1]. VVA is characterized by a constellation of symptoms, that may affect daily activities, sexuality, relationships, and quality of life [3]. Early recognition and effective treatment of VVA may enhance sexual health and the quality of life of women and their partners. Some vulvar conditions such as lichen sclerosus are more prevalent in the postmenopausal years. Lichen sclerosus has been suggested as a precursor of Vulvar squamous cell carcinoma. The vulvar exam in post-menopausal women plays an essential role in prevention of cancer because it allows to identify women who should undergo vulvar skin biopsy in order to early detect pre-neoplastic lesions for early diagnosis of cancer of the vulva.

Encefalopatia di Wernicke in corso di iperemesi gravidica

L'encefalopatia di Wernicke in corso di iperemesi gravidica è un'entità patologica estremamente rara. Il ruolo della risonanza magnetica, in tale condizione morbosa, è quello di svelare precocemente le caratteristiche alterazioni di segnale a carico del Sistema Nervoso Centrale, in modo da consentire un adeguato intervento terapeutico.

Fourth cranial nerve: surgical anatomy in the subtemporal transtentorial approach and in the pretemporal combined inter-intradural approach through the fronto-temporo-orbito-zygomatic craniotomy. A cadaveric study

Despite the recent progress in surgical technology in the last decades, the surgical treatment of skull base lesions still remains a challenge. The purpose of this study was to assess the anatomy of the tentorial and cavernous segment of the fourth cranial nerve as it appears in two different surgical approaches to the skull base: subtemporal transtentorial approach and pretemporal fronto-orbito-zygomatic approach. Four human cadaveric fixed heads were used for the dissection. Using both sides of each cadaveric head, we made 16 dissections: 8 with subtemporal transtentorial technique and 8 with pretemporal fronto-orbito-zygomatic approach. The first segment that extends from the initial point of contact of the fourth cranial nerve with the tentorium (point Q) to its point of entry into its dural channel (point D) presents an average length of 13.5 mm with an extremely wide range and varying between 3.20 and 9.3 mm. The segment 2, which extends from point D to the point of entry into the lateral wall of the cavernous sinus, presents a lesser interindividual variability (mean 10.4 mm, range 15.1-5.9 mm). A precise knowledge of the surgical anatomy of the fourth cranial nerve and its neurovascular relationships is essential to safely approach. The recognition of some anatomical landmarks allows to treat pathologies located in regions of difficult surgical access even when there is an important subversion of the anatomy.

Lung cancer screening with low dose CT: experience at Campus Bio-Medico of Rome on 1500 patients

AIM

The main purpose of our project was to evaluate the prevalence of lung cancer in high risk, asymptomatic individuals in addition to quantifying the rate of surgically resectable tumors, and evaluating the role of lung cancer with low dose computed tomography (LDCT) as a tool for lung cancer screening.

METHODS

Between June 2011 and March 2014, 1500 volunteers at high risk for lung cancer were enrolled in our study and underwent LDCT in our institution. The subsequent diagnostic and therapeutic steps were planned in relation to the results emerging from LDCT. To evaluate speed and type of growth, solid nodules ≤4 mm were reassessed with annual LDCT, those >4-6 mm or >6-8 mm were reassessed with LDCT in 6 or 3 months while nodules suspicious for malignancy were investigated with PET-CT or biopsy according to NCCN guidelines.

RESULTS

Non-calcified nodules were detected in 525 subjects (35% of population): among these 42% had a diameter ≤4 mm, 43% had a diameter >5 mm but <10 mm, 3% appeared as "ground glass" lesions, and 63 (12% of detected nodules) had malignant characteristics (irregular margins, retraction of the surrounding parenchyma, diameter >10 mm). Among the 63 patients who underwent PET-CT or biopsy, 25 cases resulted positive for lung cancer (1.7% of population). These patients underwent surgical treatment with histological detection of tumors in stages IA, IB or IIB.

CONCLUSION

Our study confirmed the emerging data on the use of LDCT as a screening tool for lung neoplasm in individuals at risk. Due to the LDCT low rate of specificity complementary biomarkers are required to properly define patients at risk and to reduce the number of further radiological examinations.

Body composition and cardiac dimensions in elite rhythmic gymnasts

AIM

Rhythmic gymnasts are often believed to be a population at risk of malnutrition because of their tendency to keep a low weight and a lean appearance for better athletic performance, and because they start intensive training at a very young age. The purpose of this study was to evaluate in adolescent elite gymnasts the effects of physical activity on body composition and cardiac morphology and function.

METHODS

Sixteen national level rhythmic gymnasts and 16 control adolescent female underwent anthropometric measurements, bioelectric impedance and echocardiography to assess body composition and cardiac morphology and function.

RESULTS

As compared to controls, gymnasts had lower body mass index (16.9±1.1 vs. 18.7±1.0, P<0.001), fatty mass (14.2±4.5 vs. 15.8±2.9 %, P<0.05) and greater fat-free mass (84.0±4.7 vs. 80.5±5.0 %, P<0.05), left ventricular end-diastolic dimension (4.7±0.4 vs. 4.4±0.3 cm) and left ventricular mass, as absolute (132.8±21.2 vs. 112.5±22.8 g, P<0.01) and indexed (44.5±9.3 vs. 36.1±8.2 g/m2.7, P<0.01). Left ventricular mass was directly related to fat-free mass as absolute (r=0.37, P<0.05) and indexed (r=0.43, P<0.02).

CONCLUSION

Body composition analysis showed a lower percentage of body fat in the gymnasts, together with a higher percentage of fat-free mass. Echocardiographic findings indicate that elite rhythmic gymnastics present left ventricular remodeling as training-induced cardiac adaptation. Intensive training, dietary attitude and evident leanness of rhythmic gymnasts are not associated with cardiac abnormalities, as it is the case of pathological leanness.

Sarcoglycan complex in masseter and sternocleidomastoid muscles of baboons: an immunohistochemical study

The sarcoglycan complex consists of a group of single-pass transmembrane glycoproteins that are essential to maintain the integrity of muscle membranes. Any mutation in each sarcoglycan gene causes a series of recessive autosomal dystrophin-positive muscular dystrophies. Negative fibres for sarcoglycans have never been found in healthy humans and animals. In this study, we have investigated whether the social ranking has an influence on the expression of sarcoglycans in the skeletal muscles of healthy baboons. Biopsies of masseter and sternocleidomastoid muscles were processed for confocal immunohistochemical detection of sarcoglycans. Our findings showed that baboons from different social rankings exhibited different sarcoglycan expression profiles. While in dominant baboons almost all muscles were stained for sarcoglycans, only 55% of muscle fibres showed a significant staining. This different expression pattern is likely to be due to the living conditions of these primates. Sarcoglycans which play a key role in muscle activity by controlling contractile forces may influence the phenotype of muscle fibres, thus determining an adaptation to functional conditions. We hypothesize that this intraspecies variation reflects an epigenetic modification of the muscular protein network that allows baboons to adapt progressively to a different social status.

Colloidal Nanoparticle Interaction Transition during Solvent Evaporation Investigated by in-Situ Small-Angle X-ray Scattering

In-situ scanning small-angle X-ray scattering (SAXS) experiments have been performed to probe the drying of a single suspended droplet of silica colloids. It has been demonstrated that the formation of a nanoparticle shell during drying can be confirmed just by measuring the temporal evolution of the spatial transmission profile across the drying droplet. The shrinkage of the droplet stops once the shell is formed. The temporal dependence of the shell thickness and droplet radius has been estimated by quantitative analysis of the functionality of the transmission profiles. It is revealed that the position of the correlation peak originating from interactions between silica nanoparticles evolves linearly during the initial stage of drying and exhibits sigmoidal growth behavior in later stages. The interaction between colloidal particles in different drying stages has been investigated. We provide experimental confirmation of the transition from repulsive interaction to a capillary-driven short-range attraction during shell formation. The present work demonstrates that in-situ scanning SAXS on a suspended droplet is an invaluable technique for monitoring the dynamic self-organization of colloids as it probes the drying of complex fluids without the interference of a substrate.

Laser-ablated titania nanoparticles for aqueous processed hybrid solar cells

Titania nanoparticles are produced by laser ablation in liquid in order to initiate functionalization of titania with the polymer for the active layer. By combining these titania nanoparticles and water-soluble poly[3-(potassium-6-hexanoate)thiophene-2,5-diyl] (P3P6T) hybrid solar cells are realized.

Hashimoto thyroiditis onset after laparoscopic removal of struma ovarii: an overview to unravel a rare and intriguing finding

Struma ovarii is an uncommon type of ovarian tumor derived by germinal cells, characterized by the predominance of thyroid tissue (> 50%); 90-95% of these formations are benign and mainly affect the left ovary, while in 6% of the cases struma ovarii is bilateral. The malignant transformation is a rare condition that often occurs after 50 years. In most instances, diagnosis of malignant struma ovarii is made postoperatively during histological analysis. This tumor appears to derive by one germinal cell through loss of heterozygosity of the androgen receptor gene and of the X chromosome. Clinical symptoms comprise abdominopelvic mass, lower abdominal pain, abnormal vaginal bleeding, and ascites (the occurrence of this condition has been observed in one-third of the cases). The patients with struma ovarii generally do not manifest symptoms related to thyroid hyperfunction, reported only in 8% of the cases, and due to hyperstimulation of the thyroid by auto-antibodies. Thyroid tissue of the struma ovarii, often embedded in a teratoma, may be papillary, follicular or with mixed pattern and it can include elements of mucinous cystoadenomas, Brenner's tumor or carcinoid or melanomas cells. Here the authors report their experience with an unusual case of Hashimoto thyroiditis onset after laparoscopic removal of struma ovarii.

Use of intermediate focus for grazing incidence small and wide angle x-ray scattering experiments at the beamline P03 of PETRA III, DESY

We describe the new experimental possibilities of the micro- and nanofocus X-ray scattering beamline P03 of the synchrotron source PETRA III at DESY, Hamburg (Germany), which arise from experiments with smaller beam sizes in the micrometer range. This beamline has been upgraded recently to perform new kinds of experiments. The use of an intermediate focus allows for reducing the beam size of microfocused hard X-rays while preserving a large working distance between the focusing elements and the focus position. For the first time, this well-known methodology has been employed to grazing incidence small- and wide-angle X-ray scattering (GISAXS/GIWAXS). As examples, we highlight the applications to in situ studies using microfluidic devices in GISAXS geometry as well as the investigation of the crystallinity of thin films in GIWAXS geometry.

Probing evaporation induced assembly across a drying colloidal droplet using in situ small-angle X-ray scattering at the synchrotron source

Colloidal particles in a tiny drying droplet are forced to assemble due to attractive capillary forces. Jamming of the particles throughout the droplet remains either isotropic or anisotropic depending upon the drying kinetics and the physicochemical environment. In this work, we explore the dynamical evolution of such an assembly process across a single evaporative droplet by in situ scanning small-angle scattering using a micro-focused X-ray beam at the synchrotron source. A methodology has been elucidated to differentiate quantitatively between the isotropic and the anisotropic jamming process. Switching of jamming behaviour depending on the initial particle volume fraction in the droplet has been demonstrated. Three distinct stages of assembly, associated with droplet shrinkage, have been revealed even during isotropic jamming. This is in contrast to the drying of a pure liquid droplet under diffusion limited evaporation. It has been established that such in situ scattering measurements can also be used to estimate the temporal evolutions of the viscosity of a drying suspension as well as the diffusivity of nanoparticles in a droplet.

Time resolved growth of membrane stabilized silver NPs and their catalytic activity

Growth kinetics of membrane stabilized silver nanoparticles have been studied for the first time with time resolved in situ SAXS. The catalytic application of nanocomposite membranes thus formed has also been explored.

Effects of the commensurability and disorder on friction for the system Xe/Cu

We present molecular dynamics simulations of static friction for a monolayer of Xe deposited on a thick slab of Cu for two different geometries. The interaction potential between Xe and Cu has been derived from DFT calculations. The first geometry is the commensurate adsorption geometry (√3 × √3 suggested by LEED, corresponding to a coverage 1/3, where all Xe atoms are on top positions. The second one corresponds to a coverage 0.36 and is characterized by a large surface unit cell, containing 9 Xe atoms in different disordered positions. This large unit cell mimics an incommensurate case. Our analysis points out the effect of the order/disorder in tribological properties of a realistic three-dimensional system.

Pit and fissure sealants: review of literature and application technique

Molars and premolars are the most vulnerable teeth to caries attack. The high susceptibility of these teeth to caries is directly related to morphology of their occlusal surface that prevents both chemical cleaning by saliva and mechanical cleaning by toothbrush. Pit and fissures are therefore the most prone areas to caries and need special protection to prevent carious lesions. Fluoride is the only chemical element used for caries prevention. In fact, it favors the remineralisation of initial lesions, prevents the production of polysaccharides essential for the development and sustainment of bacterial plaque, and the absorption of salivary glycoprotein. Fluoride also reinforces enamel, making it less susceptible to caries. Two methods of fluoroprophylaxis have been proposed: the first is the systemic fluoroprophylaxis which is particularly efficient in preventing interproximal caries, but it does not form an adequate protective barrier on the occlusal surfaces; the other is the topical application of a fluoride gel to the tooth surface, although this second method does not significantly reduce the incidence of caries. The efficacy of the sealing procedures depends on the correct application technique. Observing an operative protocol will ensure a longer lasting retention of the sealant on the occlusal surface and subsequently prolongs the protection against caries.