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OBJECTIVE: Despite advances in perioperative care, hepatectomy remains associated with morbidity rates of up to 40%. Currently, available nomograms for predicting severe post-hepatectomy complications do not include early postoperative data. This retrospective observational study aimed to determine whether the parameters routinely measured in patients admitted to the Intensive Care Unit (ICU) after hepatectomy could represent risk factors for severe morbidity and to propose a nomogram scoring system to predict severe postoperative complications. PATIENTS AND METHODS: 411 adult patients who underwent elective hepatectomy at a high-volume tertiary care center for hepatic surgery from December 2016 to June 2022 were enrolled. The primary outcome was the assessment of predictors of 30-day severe postoperative complications following hepatectomy, defined as Clavien-Dindo grade 3a or higher. As a secondary outcome, we aimed to develop an easy-to-use scoring system to estimate the risk of severe postoperative complications. RESULTS: Severe complications occurred in 78 patients (19%). The final model included body mass index, preoperative bilirubin level, and ICU data (i.e., pH, lactate clearance, arterial lactate concentration 12 hours after ICU admission, need for packed red blood cell transfusions, and length of stay). Notably, the latter three variables were proven to be independent predictors of the outcomes. The model showed an overall good fit (C-index=0.754, corrected Dxy=0.692). A calibration plot using bootstrap internal validity resampling confirmed the stability of the model (mean absolute error=0.017, root mean square error of approximation=0.00051). CONCLUSIONS: We developed an accurate and practical scoring system based on preoperative and early postoperative data to predict poor outcomes after hepatectomy. Further external validation on larger series could lead to the integration of such a tool in the routine clinical practice to support patients' management and early warning during ICU stay. [ABSTRACT FROM AUTHOR]

In this work, nonlinear variational optimization is used for obtaining minimal seeds for the formation of turbulent bands in channel flow. Using nonlinear optimization together with energy bisection, we have found that the minimal energy threshold for obtaining spatially patterned turbulence scales with Re-8.5 for Re > 1000. The minimal seed, which is different to that found in a much smaller domain, is characterized by a spot-like structure surrounded by a low-amplitude large-scale quadrupolar flow filling the whole domain. This minimal-energy perturbation of the laminar flow has dominant wavelengths close to 4 in the streamwise direction and 1 in the spanwise direction, and is characterized by a spatial localization increasing with the Reynolds number. At Re ≲ 1200, the minimal seed evolves in time, creating an isolated oblique band, whereas for Re ≲ 1200, a quasi-spanwise-symmetric evolution is observed, giving rise to two distinct bands. A similar evolution is found also at low Re for non-minimal optimal perturbations. This highlights two different mechanisms of formation of turbulent bands in channel flow, depending on the Reynolds number and initial energy of the perturbation. The selection of one of these two mechanisms appears to be dependent on the probability of decay of the newly created stripe, which increases with time, but decreases with the Reynolds number. [ABSTRACT FROM AUTHOR]

A new mathematical framework is proposed for characterizing the coherent motion of fluctuations around a mean turbulent channel flow. We search for statistically invariant coherent solutions of the unsteady Reynolds-averaged Navier–Stokes equations written in a perturbative form with respect to the turbulent mean flow, using a suitable approximation of the Reynolds stress tensor. This is achieved by setting up a continuation procedure of known solutions of the perturbative Navier–Stokes equations, based on the continuous increase of the turbulent eddy viscosity towards its turbulent value. The recovered solutions, being sustained only in the presence of the Reynolds stress tensor, are representative of the statistically coherent motion of turbulent flows. For small friction Reynolds number and/or domain size, the statistically invariant motion is almost identical to the corresponding invariant solution of the Navier–Stokes equations. Whereas, for sufficiently large friction number and/or domain size, it considerably departs from the starting invariant solution of the Navier–Stokes equations, presenting spatial structures, main wavelengths and scaling very close to those characterizing both large- and small-scale motion of turbulent channel flows. This article is part of the theme issue 'Mathematical problems in physical fluid dynamics (part 2)'. [ABSTRACT FROM AUTHOR]

Recently, many authors have investigated the origin and growth of turbulent bands in shear flows, highlighting the role of streaks and their inflectional instability in the process of band generation and sustainment. Recalling that streaks are created by an optimal transient growth mechanism, and motivated by the observation of a strong increase of the disturbance kinetic energy corresponding to the creation of turbulent bands, we use linear and nonlinear energy optimisations in a tilted domain to unveil the main mechanisms allowing the creation of a turbulent band in a channel flow. Linear transient growth analysis shows an optimal growth for wavenumbers having an angle of approximately 35°, close to the peak values of the premultiplied energy spectra of direct numerical simulations. This linear optimal perturbation generates oblique streaks, which, for a sufficiently large initial energy, induce turbulence in the whole domain, due to the lack of spatial localisation. However, spatially localised perturbations obtained by adding nonlinear effects to the optimisation or by artificially confining the linear optimal to a localised region in the transverse direction are characterised by a large-scale flow and lead to the generation of a localised turbulent band. These results suggest that two main elements are needed for inducing turbulent bands in a tilted domain: (i) a linear energy growth mechanism, such as the lift-up, for generating large-amplitude flow structures, which produce inflection points; (ii) spatial localisation, linked to the presence or generation of large-scale vortices. We show that these elements alone generate isolated turbulent bands also in large non-tilted domains. [ABSTRACT FROM AUTHOR]

Summary: A 3‐year‐old Warmblood gelding was evaluated for intermittent respiratory distress and an inspiratory noise. These signs were mainly observed at exercise but sometimes occurred at rest as well. At the age of 2 months, a severe episode of respiratory distress had necessitated a temporary tracheotomy, which had then healed uneventfully. Examination of the patient and resting endoscopy revealed no structural laryngeal alterations. Exercise endoscopy revealed episodes of active bilateral laryngeal adduction during inspiration. Spirometrically, a corresponding impairment of inspiratory airflow was identified. These abnormalities were most pronounced at the trot but they occurred at magnitudes of inspiratory airflow lower than those inducing dynamic arytenoid collapse in horses with recurrent laryngeal neuropathy. Therefore, the diagnosis of a laryngeal dyskinesia characterised by an active bilateral arytenoid adduction during inspiration was made. No specific treatment was implemented. Three years later, the owner reported that the condition was markedly improved and the horse was used for pleasure riding. [ABSTRACT FROM AUTHOR]

Summary: Background: Guttural pouch mycosis (GPM) is a cause of nasal discharge, dysphagia and fatal haemorrhage in the horse. Objectives: To report the complications and success of salpingopharyngeal fistulation in horses with GPM. We hypothesised that creating a direct static opening into the guttural pouch from the pharynx would cause a regression of fungal plaques due to a change in the guttural pouch environment and that this treatment would result in resolution of infection prior to secondary complications. Study design: Retrospective case series. Methods: The medical records of all horses diagnosed with GPM that were presented to New Bolton Center between the years 2006 and 2017 were examined retrospectively. Seven cases of guttural pouch mycosis treated with salpingopharyngostomy without other surgical intervention were included. Information collected included signalment, presenting complaint, which pouch was affected, size and location of the plaques, laryngeal and pharyngeal function, concurrent medical therapy, location of the fistula, surgical time, time to resolution of clinical signs, time to full resolution of the mycotic plaque, and patency of the salpingopharyngostomy site. Results: Nasal discharge resolved in 10–30 days post‐operatively in all cases where nasal discharge was present. The mycotic plaques showed complete resolution at time points ranging from 1 to 6 months post‐operatively. No case developed epistaxis or neurological deficits post‐operatively that were not present at presentation. Main limitations: There were differing adjunctive treatments between cases. This technique is not appropriate for horses that have had epistaxis or are currently bleeding. Conclusions: Salpingopharyngostomy can minimise cost of treatment, be performed on an outpatient basis and provide better exposure of the infected area with few complications. This case series documents seven cases treated with this method that resolved the infection without any further complications of the mycosis. [ABSTRACT FROM AUTHOR]

That situation is very different from the horse that has an underlying neuromuscular problem that is causing a primary functional inability of the oropharynx resulting in the dysphagia and possibly persistent palate displacement. If the palate is persistently above the epiglottis despite multiple stimulated swallows, a lateral radiograph (as was performed in this case report) can yield valuable information about any structural abnormalities associated with the epiglottis or palate. Infrequently entrapment of the epiglottis can precipitate persistent displacement of the palate, or the ventral surface of the epiglottis can be very abnormal and result in significant performance problem or dysphagia while appearing normal on the dorsal surface. [Extracted from the article]

Summary: Recurrent laryngeal neuropathy appears to be a simple problem that should have a simple solution, yet the complexity and dynamic nature of laryngeal function is underappreciated. This review highlights the challenges and accomplishments that work towards that greater understanding of what is necessary to find a successful solution. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Alpha-lipoic acid is a natural molecule, which directly or by means of its reduced form, dihydrolipoic acid, exerts antioxidant, anti-inflammatory and immunomodulatory activities, very helpful also in preventing miscarriage and preterm delivery. Used as dietary supplement alpha-lipoic acid was demonstrated to be safe for living organisms even when administered at high doses. However, no study was made so far to verify the safety of its continuous administration on a substantial number of pregnant women. The present investigation was performed to answer this issue. PATIENTS AND METHODS: An observational retrospective study was carried out analyzing 610 expectant mothers. They had been treated daily by oral route with 600 mg alpha-lipoic acid, for at least 7 weeks during gestation. The primary outcome was to verify alpha-lipoic acid safety in the mother and infant. Maternal safety was assessed by monitoring for adverse reactions, physical and clinical examination, including a morbidity assessment. Laboratory and clinical examinations were performed monthly. Neonatal safety was assessed by the evaluation of birth weight, gestational age, Apgar scores, neonatal death with the related cause of death. Data collected from the Birth Registry of Campania Region were used as control. RESULTS: This study provided a very clear and reassuring picture about the safety of alpha-lipoic acid oral treatment during pregnancy. No adverse effect was noticed in mothers or newborns. The two sets of monitored data, from treated and controls, were completely superimposable or, in some cases, better in alpha-lipoic acid group. CONCLUSIONS: Our results open a reassuring scenario regarding the administration of alpha-lipoic acid during pregnancy. [ABSTRACT FROM AUTHOR]

This review outlines the recent advances in the knowledge on aerobic and respiratory growth of lactic acid bacteria, focusing on the features of respiration-competent lactobacilli. The species of the genus Lactobacillus have been traditionally classified as oxygen-tolerant anaerobes, but it has been demonstrated that several strains are able to use oxygen as a substrate in reactions mediated by flavin oxidases and, in some cases, to synthesize a minimal respiratory chain. The occurrence of genes related to aerobic and respiratory metabolism and to oxidative stress response apparently correlates with the taxonomic position of lactobacilli. Members of the ecologically versatile Lactobacillus casei, L. plantarum and L. sakei groups are apparently best equipped to deal with aerobic/respiratory growth. The shift from anaerobic growth to aerobic (oxygen) and/or respiratory promoting (oxygen, exogenous haem and menaquinone) conditions offers physiological advantages and affects the pattern of metabolite production in several species. Even if this does not result in dramatic increases in biomass production and growth rate, cells grown in these conditions have improved tolerance to heat and oxidative stresses. An overview of benefits and of the potential applications of Lactobacillus cultures grown under aerobic or respiratory conditions is also discussed. [ABSTRACT FROM AUTHOR]

Background and study aims: Colorectal cancer (CRC) screening aims to reduce mortality by detecting cancers at an early stage and removing adenomatous polyps at an acceptable cost. The aim of the current study were to assess the outcomes and costs of the first two biennial rounds of a population-based CRC screening program using the immunochemical fecal occult blood test (i-FOBT) in a northern Italian province. Methods: All residents aged 50-69 yearswere invited to take part in a biennial screening program using a 1-day i-FOBT, followed by colonoscopy in positive individuals. The i-FOBT uptake, compliance to colonoscopy, detection rate for cancer or advanced adenomas according to age and sex, and direct cost analysis were carried out separately for the 1st and 2nd rounds of screening. Results: In 78083 (1st round) and 81619 (2nd round) individuals whowere invited to screening, the participation rates were 49.7% and 54.4% and i-FOBT positivity rates were 6.2% and 5.8 %, respectively. Detection rates for cancer and advanced adenomas were lower in the 2nd screening compared with the 1st one (1.6‰ vs. 2.5‰ for cancers and 15.8‰ vs. 17.9‰ for advanced adenomas, respectively), whereas positive predictive values for cancer and advanced adenoma were similar in both rounds. In 165 adenocarcinomas detected, 52% were Dukes' stage A and 21% were stage B. All cost indicators were slightly higher in the 1st round of screening compared with the 2nd. The direct cost per cancer or advanced adenoma detection was similar in the two rounds (€1252 and €1260, respectively). Conclusions: Compliance and diagnostic yield of i-FOBT screening were satisfactory. Most detected cancers were at a very early stage. Program costs were reasonable and did not increase with repeat screening. Screening could contribute to decreasing the cost of CRC care by improving the stage at diagnosis. [ABSTRACT FROM AUTHOR]

Aim: To compare the changes in the upper lip (UL) length after performing incisions with scalpel and electrocautery for maxillary impaction. Patients and methods: Patients submitted to maxillary superior repositioning greater than 3 mm were randomly assigned to two groups. Only cases with a smaller maxillary advancement were included. Incisions were made with scalpel in Group 1 and with electrocautery in Group 2. Pre- and post-operative lateral cephalometric radiographs were used to calculate the changes in the UL length (subnasal and stomium superior), and superior movement of the UL relative to maxillary impaction. Results: Sixteen patients that underwent maxillary impaction were evaluated. Four patients were previously excluded. The mean maxillary impaction was 4.85 mm and the mean advancement was 1.87 mm. The mean UL shortening was 0.53 mm, and the mean UL superior movement relative to maxillary impaction was 11.88%. In the five patients of Group 1, the mean lip shortening was 0.32 mm and superior movement of the UL relative to maxillary impaction was 10.91% on average. The seven patients of Group 2 presented a mean lip shortening of 0.68 mm, and superior movement of the UL relative to maxillary impaction was 15.41% on average. Conclusion: Although Group 2 showed greater UL shortening than Group 1, it was not statistically significant. [ABSTRACT FROM AUTHOR]

Summary Reasons for performing study: Loss of arytenoid abduction is a common post operative complication of laryngoplasty without a definitive cause. It has been a clinical impression during laryngoplasty surgery that there is great conformational variability along the caudal edge of the Thoroughbred cricoid cartilage that could impact post operative retention of suture position. A change in suture position would probably lead to some loss of abduction. Defining any structural variability of the cricoid would be an initial step in determining whether this variability could impact on the retention of suture position. Hypothesis: Anatomical variations in the larynx of Thoroughbred horses may be detected and measured using objective analysis and computed tomography. Methods: Larynges were harvested from 15 mature Thoroughbred horses. Helical CT scans were performed on each specimen. Three independent observers performed a series of measurements on 2D and 3D reconstruction images using digital software. Measurements included the lateral cricoid angle, the caudal cricoid prominences, the distance to the cricoid slope, the angle of the cricoarytenoid joints (CAJ), the cricoid thickness and the suture angle. Mean, standard deviation, coefficient of variation and linear regression analysis were performed among all observers and all measurements. Results: Notable conformational differences were evident on the 3D reconstructions. The highest degree of variability was found in 3 measurements: the distance to the lateral cricoid slope, the lateral cricoid angle and the cricoid thickness. A larger left CAJ angle directly and significantly correlated with a larger suture angle. Conclusions: There are notable conformational differences among cricoid specimens in the Thoroughbred larynx. Potential relevance: The morphometric differences identified may impact on optimal prosthesis placement and long-term retention. Since a larger lateral cricoid angle may facilitate abduction loss secondary to a displaced and loosened suture, alternative techniques for suture placement may be of value to prevent arytenoid abduction loss. [ABSTRACT FROM AUTHOR]

Summary Reasons for performing study: Although well documented in racehorses, there is paucity in the literature regarding the prevalence of dynamic upper airway abnormalities in nonracing performance horses. Objective: To describe upper airway function of nonracing performance horses with abnormal respiratory noise and/or poor performance via exercising upper airway videoendoscopy. Methods: Medical records of nonracing performance horses admitted for exercising evaluation with a chief complaint of abnormal respiratory noise and/or poor performance were reviewed. All horses had video recordings of resting and exercising upper airway endoscopy. Relationships between horse demographics, resting endoscopic findings, treadmill intensity and implementation of head and neck flexion during exercise with exercising endoscopic findings were examined. Results: Dynamic upper airway obstructions were observed in 72% of examinations. Head and neck flexion was necessary to obtain a diagnosis in 21 horses. Pharyngeal wall collapse was the most prevalent upper airway abnormality, observed in 31% of the examinations. Complex abnormalities were noted in 27% of the examinations. Resting laryngeal dysfunction was significantly associated with dynamic arytenoid collapse and the odds of detecting intermittent dorsal displacement of the soft palate (DDSP) during exercise in horses with resting DDSP was only 7.7%. Exercising endoscopic observations were different from the resting observations in 54% of examinations. Conclusions: Dynamic upper airway obstructions were common in nonracing performance horses with respiratory noise and/or poor performance. Resting endoscopy was only helpful in determining exercising abnormalities with recurrent laryngeal neuropathy. Potential relevance: This study emphasises the importance of exercising endoscopic evaluation in nonracing performance horses with abnormal respiratory noise and/or poor performance for accurate assessment of dynamic upper airway function. [ABSTRACT FROM AUTHOR]

Summary A case of paranasal sinus fibromatosis in an 11-year-old Thoroughbred gelding is reported. At admission the gelding underwent a unilateral frontal sinusotomy and a paranasal sinus mass was extensively debulked. The mass was diagnosed via histopathology as a desmoid fibromatosis with bone invasion, reactive osteoclastic osteolysis and osteoproliferation. The gelding had radiographic evidence of slow recurrence of the mass 8 months post operatively. The histopathological appearance and short-term outcome are presented for this previously undiagnosed condition of the horse. Recognition of paranasal fibromatosis and the resultant differentiation from other types of paranasal sinus neoplasia may allow for improved prognostication of equine sinus lesions. [ABSTRACT FROM AUTHOR]