Development and multicentre validation of the FLEX score: personalised preoperative surgical risk prediction using attention-based ICD-10 and Current Procedural Terminology set embeddings.

BACKGROUND: Preoperative knowledge of surgical risks can improve perioperative care and patient outcomes. However, assessments requiring clinician examination of patients or manual chart review can be too burdensome for routine use. METHODS: We conducted a multicentre retrospective study of 243 479 adult noncardiac surgical patients at four hospitals within the Mass General Brigham (MGB) system in the USA. We developed a machine learning method using routinely collected coding and patient characteristics data from the electronic health record which predicts 30-day mortality, 30-day readmission, discharge to long-term care, and hospital length of stay. RESULTS: Our method, the Flexible Surgical Set Embedding (FLEX) score, achieved state-of-the-art performance to identify comorbidities that significantly contribute to the risk of each adverse outcome. The contributions of comorbidities are weighted based on patient-specific context, yielding personalised risk predictions. Understanding the significant drivers of risk of adverse outcomes for each patient can inform clinicians of potential targets for intervention. CONCLUSIONS: FLEX utilises information from a wider range of medical diagnostic and procedural codes than previously possible and can adapt to different coding practices to accurately predict adverse postoperative outcomes.

Development and prospective validation of postoperative pain prediction from preoperative EHR data using attention-based set embeddings.

Preoperative knowledge of expected postoperative pain can help guide perioperative pain management and focus interventions on patients with the greatest risk of acute pain. However, current methods for predicting postoperative pain require patient and clinician input or laborious manual chart review and often do not achieve sufficient performance. We use routinely collected electronic health record data from a multicenter dataset of 234,274 adult non-cardiac surgical patients to develop a machine learning method which predicts maximum pain scores on the day of surgery and four subsequent days and validate this method in a prospective cohort. Our method, POPS, is fully automated and relies only on data available prior to surgery, allowing application in all patients scheduled for or considering surgery. Here we report that POPS achieves state-of-the-art performance and outperforms clinician predictions on all postoperative days when predicting maximum pain on the 0-10 NRS in prospective validation, though with degraded calibration. POPS is interpretable, identifying comorbidities that significantly contribute to postoperative pain based on patient-specific context, which can assist clinicians in mitigating cases of acute pain.

Roles of inter- and intramolecular tryptophan interactions in membrane-active proteins revealed by racemic protein crystallography.

Tryptophan is frequently found on the surface of membrane-associated proteins that interact with the lipid membrane. However, because of their multifaceted interactions, it is difficult to pinpoint the structure-activity relationship of each tryptophan residue. Here, we describe the use of racemic protein crystallography to probe dedicated tryptophan interactions of a model tryptophan-rich bacteriocin aureocin A53 (AucA) by inclusion and/or exclusion of potential ligands. In the presence of tetrahedral anions that are isosteric to the head group of phospholipids, distinct tryptophan H-bond networks were revealed. H-bond donation by W40 was critical for antibacterial activity, as its substitution by 1-methyltryptophan resulted in substantial loss of activity against bacterial clinical isolates. Meanwhile, exclusion of tetrahedral ions revealed that W3 partakes in formation of a dimeric interface, thus suggesting that AucA is dimeric in solution and dissociated to interact with the phosphate head group in the presence of the lipid membrane. Based on these findings, we could predict the tryptophan residue responsible for activity as well as the oligomeric state of a distant homologue lacticin Q (48%).

Association of Intraoperative Opioid Administration With Postoperative Pain and Opioid Use.

Importance: Opioids administered to treat postsurgical pain are a major contributor to the opioid crisis, leading to chronic use in a considerable proportion of patients. Initiatives promoting opioid-free or opioid-sparing modalities of perioperative pain management have led to reduced opioid administration in the operating room, but this reduction could have unforeseen detrimental effects in terms of postoperative pain outcomes, as the relationship between intraoperative opioid usage and later opioid requirements is not well understood. Objective: To characterize the association between intraoperative opioid usage and postoperative pain and opioid requirements. Design, Setting, and Participants: This retrospective cohort study evaluated electronic health record data from a quaternary care academic medical center (Massachusetts General Hospital) for adult patients who underwent noncardiac surgery with general anesthesia from April 2016 to March 2020. Patients who underwent cesarean surgery, received regional anesthesia, received opioids other than fentanyl or hydromorphone, were admitted to the intensive care unit, or who died intraoperatively were excluded. Statistical models were fitted on the propensity weighted data set to characterize the effect of intraoperative opioid exposures on primary and secondary outcomes. Data were analyzed from December 2021 to October 2022. Exposures: Intraoperative fentanyl and intraoperative hydromorphone average effect site concentration estimated using pharmacokinetic/pharmacodynamic models. Main Outcomes and Measures: The primary study outcomes were the maximal pain score during the postanesthesia care unit (PACU) stay and the cumulative opioid dose, quantified in morphine milligram equivalents (MME), administered during the PACU stay. Medium- and long-term outcomes associated with pain and opioid dependence were also evaluated. Results: The study cohort included a total of 61 249 individuals undergoing surgery (mean [SD] age, 55.44 [17.08] years; 32 778 [53.5%] female). Increased intraoperative fentanyl and intraoperative hydromorphone were both associated with reduced maximum pain scores in the PACU. Both exposures were also associated with a reduced probability and reduced total dosage of opioid administration in the PACU. In particular, increased fentanyl administration was associated with lower frequency of uncontrolled pain; a decrease in new chronic pain diagnoses reported at 3 months; fewer opioid prescriptions at 30, 90, and 180 days; and decreased new persistent opioid use, without significant increases in adverse effects. Conclusions and Relevance: Contrary to prevailing trends, reduced opioid administration during surgery may have the unintended outcome of increasing postoperative pain and opioid consumption. Conversely, improvements in long-term outcomes might be achieved by optimizing opioid administration during surgery.

Age-Dependent Electroencephalogram Features in Infants Under Spinal Anesthesia Appear to Mirror Physiologic Sleep in the Developing Brain: A Prospective Observational Study.

BACKGROUND: Infants under spinal anesthesia appear to be sedated despite the absence of systemic sedative medications. In this prospective observational study, we investigated the electroencephalogram (EEG) of infants under spinal anesthesia and hypothesized that we would observe EEG features similar to those seen during sleep. METHODS: We computed the EEG power spectra and spectrograms of 34 infants undergoing infraumbilical surgeries under spinal anesthesia (median age 11.5 weeks postmenstrual age, range 38-65 weeks postmenstrual age). Spectrograms were visually scored for episodes of EEG discontinuity or spindle activity. We characterized the relationship between EEG discontinuity or spindles and gestational age, postmenstrual age, or chronological age using logistic regression analyses. RESULTS: The predominant EEG patterns observed in infants under spinal anesthesia were slow oscillations, spindles, and EEG discontinuities. The presence of spindles, observed starting at about 49 weeks postmenstrual age, was best described by postmenstrual age ( P =.002) and was more likely with increasing postmenstrual age. The presence of EEG discontinuities, best described by gestational age ( P = .015), was more likely with decreasing gestational age. These age-related changes in the presence of spindles and EEG discontinuities in infants under spinal anesthesia generally corresponded to developmental changes in the sleep EEG. CONCLUSIONS: This work illustrates 2 separate key age-dependent transitions in EEG dynamics during infant spinal anesthesia that may reflect the maturation of underlying brain circuits: (1) diminishing discontinuities with increasing gestational age and (2) the appearance of spindles with increasing postmenstrual age. The similarity of these age-dependent transitions under spinal anesthesia with transitions in the developing brain during physiological sleep supports a sleep-related mechanism for the apparent sedation observed during infant spinal anesthesia.

Characterizing brain dynamics during ketamine-induced dissociation and subsequent interactions with propofol using human intracranial neurophysiology.

Ketamine produces antidepressant effects in patients with treatment-resistant depression, but its usefulness is limited by its psychotropic side effects. Ketamine is thought to act via NMDA receptors and HCN1 channels to produce brain oscillations that are related to these effects. Using human intracranial recordings, we found that ketamine produces gamma oscillations in prefrontal cortex and hippocampus, structures previously implicated in ketamine's antidepressant effects, and a 3 Hz oscillation in posteromedial cortex, previously proposed as a mechanism for its dissociative effects. We analyzed oscillatory changes after subsequent propofol administration, whose GABAergic activity antagonizes ketamine's NMDA-mediated disinhibition, alongside a shared HCN1 inhibitory effect, to identify dynamics attributable to NMDA-mediated disinhibition versus HCN1 inhibition. Our results suggest that ketamine engages different neural circuits in distinct frequency-dependent patterns of activity to produce its antidepressant and dissociative sensory effects. These insights may help guide the development of brain dynamic biomarkers and novel therapeutics for depression.

Opposites Attract: Electrostatically Driven Loading of Antimicrobial Peptides into Phytoglycogen Nanocarriers.

Antimicrobial peptides, such as GL13K, have a high binding selectivity toward bacterial membranes, while not affecting healthy mammalian cells at therapeutic concentrations. However, delivery of these peptides is challenging since they are susceptible to proteolytic hydrolysis and exhibit poor cellular uptake. A protective nanocarrier is thus proposed to overcome these obstacles. We investigate the potential to employ biodegradable phytoglycogen nanoparticles as carriers for GL13K using a simple loading protocol based on electrostatic association rather than chemical conjugation, eliminating the need for control of chemical cleavage for release of the peptide in situ. Both the native (quasi-neutral) and carboxymethylated (anionic) phytoglycogen were evaluated for their colloidal stability, loading capacity, and release characteristics. We show that the anionic nanophytoglycogen carries a greater cationic GL13K load and exhibits slower release kinetics than native nanophytoglycogen. Isotope exchange measurements demonstrate that the antimicrobial peptide is entrapped in the pores of the dendritic-like macromolecule, which should provide the necessary protection for delivery. Importantly, the nanoformulations are active against a Pseudomonas aeruginosa clinical isolate at concentrations comparable to those of the free peptide and representative, small molecule antibiotics. The colloidal nanocarrier preserves peptide stability and antimicrobial activity, even after long periods of storage (at least 8 months).

Evaluation of different nitrogen sources on growth and fermentation performance for enhancing ethanol production by wine yeasts.

The utilization of grape juice from low oenological value grape varieties for bioethanol production represent an alternative for diversification and value addition in viticulture. Optimizing Very High Gravity (VHG) fermentation can significantly increase ethanol productivity while reducing water and energy consumption. In this study, the impact of different nitrogen sources on growth and fermentative performance of locally selected yeast strains was investigated. Five yeast strains of species Saccharomyces cerevisiae and Zygosaccharomyces rouxii were cultured in both synthetic culture media and natural grape juice supplemented with ammonium sulfate (NH), yeast extract (YE), Fermaid K (FERM), and urea (U) at varying concentrations. Due to the very low fermentation rate, the Z. rouxii strain was excluded from the selection. The results obtained in synthetic medium showed that nitrogen sources that promoted growth (NH and YE) had minimal effects on fermentative performance and were highly dependent on the specific yeast strain. However, the combination of urea and ammonium favored the rate of sugar consumption. When validated in natural grape juice, urea combined with ammonium (U + NH 300 + 75 mg/L) improved both growth parameters and ethanol yield. Doubling the concentration (U + NH 600 + 150 mg/L) further enhanced sugar consumption and ethanol production while reducing unwanted by-products. The combined use of urea and ammonium exhibited a synergistic effect, making it a cost-effective nitrogen supplement for VHG fermentations.

Hybridization and spore dissection of native wine yeasts for improvement of ethanol resistance and osmotolerance.

Global warming has a significant impact on different viticultural parameters, including grape maturation. An increment of photosynthetic activity generates a rapid accumulation of sugars in the berry, followed by a dehydration process which leads to a higher concentration of soluble solids. This effect is exacerbated by current viticultural practices which favor the harvest of very mature grapes to obtain wines with sweet tannins. Considering the initial hyperosmotic stress conditions and the high ethanol concentration of the produced wine, fermentation of grape musts with high sugar content could be problematic for yeast starters. In the present study, we were able to obtain by classical hybridization and spore dissection methods one hybrid and one monosporic wine yeast strain with a combined ethanol and osmotolerant phenotype. The improved yeasts were tested in vinification trials with high sugar concentration and displayed excellent fermentation performance. Importantly, the obtained wines also showed good organoleptic properties during sensory analysis. Based on our results, we believed our improved hybrid and monosporic strains can be considered good alternatives to be used as yeast starters for fermentations with high sugar content.

Optimization of fermentation-relevant factors: A strategy to reduce ethanol in red wine by sequential culture of native yeasts.

Current consumer preferences are determined by well-structured, full-bodied wines with a rich flavor and with reduced alcohol levels. One of the strategies for obtaining wines with reduced ethanol content is sequential inoculation of non-Saccharomyces and Saccharomyces cerevisiae yeasts. However, different factors affect the production of metabolites like ethanol, glycerol and acetic acid by inoculated yeasts. In order to obtain low alcohol wines without quality loss, the aims of our study were: i) to determine optimum conditions (fermentation temperature and time of permanence and initial inoculum size of the non-Saccharomyces population at the beginning of the process, prior to inoculation with S. cerevisiae); ii) to validate the optimized factors; and iii) to assess sensory quality of the wines obtained after validation. Two combinations of yeasts were used in this study: Hanseniaspora uvarum BHu9/S. cerevisiae BSc114 and Candida membranaefaciens BCm71/S. cerevisiae BSc114. Optimization of three fermentation factors that affect to non-Saccharomyces yeasts prior to S. cerevisiae inoculation was carried out using a Box-Behnken experimental design. Applying the models constructed by Response Surface Methodology, the lowest ethanol production by H. uvarum BHu9/S. cerevisiae BSc114 co-culture was obtained when H. uvarum BHu9 was inoculated 48 h 37 min prior to S. cerevisiae inoculation, at a fermentation temperature of 25 °C and at an initial inoculum size of 5 × 106 cells/mL. Lowest alcohol production with C. membranaefaciens BCm71/S. cerevisiae BSc114 was observed when C. membranaefaciens BCm71 was inoculated 24 h 15 min prior to S. cerevisiae at a fermentation temperature of 24.94 °C and at an initial inoculum size of 2.72 × 106 cells/mL. The optimized conditions of the two co-cultures were subsequently submitted to lab-scale validation. Both proposed strategies yielded ethanol levels that were significantly lower than control cultures (S. cerevisiae). Wines fermented with non-Saccharomyces/Saccharomyces co-cultures under optimized conditions were also associated with higher aromatic complexity characterized by the presence of red fruit aromas, whereas wines obtained with S. cerevisiae BSc114 were described by parameters linked with high ethanol levels.

Construction of low-ethanol-wine yeasts through partial deletion of the Saccharomyces cerevisiae PDC2 gene.

We propose an alternative GMO based strategy to obtain Saccharomyces cerevisiae mutant strains with a slight reduction in their ability to produce ethanol, but with a moderate impact on the yeast metabolism. Through homologous recombination, two truncated Pdc2p proteins Pdc2pΔ344 and Pdc2pΔ519 were obtained and transformed into haploid and diploid lab yeast strains. In the pdc2Δ344 mutants the DNA-binding and transactivation site of the protein remain intact, whereas in pdc2Δ519 only the DNA-binding site is conserved. Compared to the control, the diploid BY4743pdc2Δ519 mutant strain reduced up to 7.4% the total ethanol content in lab scale-vinifications. The residual sugar and volatile acidity was not significantly affected by this ethanol reduction. Remarkably, we got a much higher ethanol reduction of 10 and 15% when the pdc2Δ519 mutation was tested in a native and a commercial wine yeast strain against their respective controls. Our results demonstrate that the insertion of the pdc2Δ519 mutation in wine yeast strains can reduce the ethanol concentration up to 1.89% (v/v) without affecting the fermentation performance. In contrast to non-GMO based strategies, our approach permits the insertion of the pdc2Δ519 mutation in any locally selected wine strain, making possible to produce quality wines with regional characteristics and lower alcohol content. Thus, we consider our work a valuable contribution to the problem of high ethanol concentration in wine.

Selection of non-Saccharomyces yeasts to be used in grape musts with high alcoholic potential: a strategy to obtain wines with reduced ethanol content.

Ethanol content of wine has increased over the last decades as consequence of searching phenolic maturity, requiring increased grape maturity. This may result in the production of wines with excessive alcohol levels (sometimes more than 15% (v/v)), sluggish and stuck fermentations and excessive volatile acidity. Many strategies to reduce ethanol in wines are being studied, and microbial methods have some additional advantages. However, because of the broad intra- and interspecies variability, new selection criteria should be included. Therefore, the goal of the present work was to design and evaluate a simple and integral procedure for non-Saccharomyces yeast selection. This strategy allowed selection of yeasts that presented successful implantation in grape must with high alcohol potential and their use in co-cultures could reduce the ethanol in wines. A total of 114 native non-Saccharomyces yeasts were assayed to determine their respiratory, fermentative and physiological characteristics of enological interest. Hanseniaspora uvarum BHu9 and BHu11, H. osmophila BHo51, Starmerella bacillaris BSb55 and Candida membranaefaciens BCm71 were selected as candidates to design co-culture starters.

Percepción de la iniciativa Instituciones Amigas de la Mujer y la Infancia (IAMI) en Cartagena, 2012 / Perception of the Mother- and Baby-Friendly Hospital Initiative (MBFHI) in Cartagena, Colombia, 2012 / Percepção da iniciativa Instituições Amigas da Mulher e a Infância (IHAC) em Cartagena, 2012

Objetivo: Establecer el grado de percepción de la implementación de los pasos de la iniciativa Instituciones Amigas de la Mujer y la Infancia (IAMI) en establecimientos de salud de la ciudad de Cartagena en 2012. Materiales y métodos: Estudio descriptivo, cuya población estuvo constituida por 21 instituciones públicas y privadas, la muestra fue de 8 instituciones seleccionadas aleatoriamente. Participó todo el personal capacitado en iniciativa de hospitales amigos de los niños que labora en las instituciones. La información fue analizada a partir de 2 instrumentos: "Evaluación del Grado de implementación de la estrategia Iniciativa de hospitales amigos de los niños" y "Formulario de autoapreciación y aplicación en instituciones hospitalarias y ambulatorios". Resultados: El grado de implementación de la iniciativa varía dependiendo de las características de la atención de la institución valorada. En el ámbito hospitalario, se encontró que disponer de una política de apoyo a la infancia, capacitación del personal -en este aspecto-, así como garantizar la calidad del parto, el inicio precoz de lactancia materna (LM) y su práctica, entre otros, (pasos 1, 2, 4 y 6) tuvieron un grado de implementación medio. Mientras que la conformación de grupos de apoyo (paso 10) presentó un grado bajo. En el nivel ambulatorio fueron los pasos 1, 4, 5 y 10 sobre los que se obtuvo un grado medio, los demás pasos mantuvieron un grado alto. Ninguna institución ofrece chupos o biberones. Conclusión: La iniciativa Instituciones Amigas de la Mujer y la Infancia en las instituciones de salud se encuentra en un grado de implementación alto y medio en los niveles de atención ambulatoria y alto, medio y bajo en el nivel hospitalario.

Objective: To establish the perception level of the implementation of the BFHI initiative stEPS in health institutions in Cartagena in 2012. Material and methods: Descriptive study in a population constituted by 21 public and private institutions, as well as all trained personnel in the initiative of baby friendly hospitals ,who work in these institutions, with a sample of 8 institutions. Information was collected by means of two instruments: "Assessment of the implementation levels of the initiative baby friendly hospitals' strategy" and "Application form of self-perception and application in hospitals and in ambulatory level". Results: The implementation level varies depending on the characteristics of each assessed institution. At hospital level the stEPS number 1, 2, 4 y 6 showed a middle implementation level, while the step number 10 indicated a low level. While at ambulatory level the stEPS number 1, 4, 5 and 10 presented a middle level, the others stEPS showed a high level. No institution offers pacifiers or baby bottles. Conclusion: Implementation of the BFHI initiative in health institutions is in a high and middle level in ambulatory institutions, while in hospitals it is in high, middle and low levels.

Objetivo: estabelecer o grau de percepção da implementação dos passos da iniciativa Instituições Amigas da Mulher e a Infância (IHAC) em estabelecimentos de saúde da cidade de Cartagena em 2012. Materiais e métodos: estudo descritivo, cuja população esteve constituída por 21 instituições públicas e privadas, a amostra foi de 8 instituições selecionadas aleatoriamente. Nelas participou tudo o pessoal capacitado em iniciativa de hospitais amigos das crianças que trabalha nas instituições. A informação foi analisada a partir de 2 instrumentos: "Avaliação do Grau de implementação da estratégia iniciativa de hospitais amigos das crianças" e "Formulário de auto-apreciação e aplicação em instituições hospitaleiras e ambulatórios". Resultados: o grau de implementação da iniciativa varia, dependendo das características da atenção da instituição valorada. No âmbito hospitaleiro, encontrou-se que dispor de uma política de apoio à infância, capacitação do pessoal -neste aspecto-, assim como garantir a qualidade d parto, o início precoce do aleitamento materno (AM) e sua prática, entre outros, (passos 1, 2, 4 e 6) tiveram um grau de implementação médio. Enquanto que a conformação de grupos de apoio (passo 10) apresentou um grau baixo. No nível ambulatório foram os passos 1, 4, 5 e 10 sobre os que se obteve um grau médio, os demais passos mantiveram um grau alto. Nenhuma instituição oferece chupetas ou biberões. Conclusão: a iniciativa Instituições Amigas da Mulher e a Infância nas instituições de saúde encontra-se em um grau de implementação alto e médio nos níveis de atenção ambulatória e alto, médio e baixo no nível hospitaleiro.

Biodiversity of Saccharomyces cerevisiae populations in Malbec vineyards from the "Zona Alta del Río Mendoza" region in Argentina.

The "Zona Alta del Río Mendoza" (ZARM) is the major Malbec grape viticulture region of Argentina. The aim of the present study was to explore Saccharomyces cerevisiae biodiversity in ZARM vineyards. Interdelta PCR and RFLP mtDNA molecular markers were applied to differentiate S. cerevisiae strains. The presence of commercial strains on ZARM vineyards was also assessed. Our results reveal a highly diverse, but genetically closely related, S. cerevisiae population (containing more than 190 molecular patterns among 590 S. cerevisiae isolates). According to the S. cerevisiae strain diversity found in vineyards, they were classified as vineyards with high and low polymorphic S. cerevisiae populations. Six vineyards showed a high polymorphic population, with more than 20 different S. cerevisiae molecular patterns. S. cerevisiae populations in these vineyards were diverse and irregularly distributed, with different strains in each vineyard site. Low polymorphic S. cerevisiae population vineyards displayed very low yeast diversity, with only 9 to 10 different S. cerevisiae strains and presence of two commercial strains widely distributed. Population diversity estimators were calculated to determine the population structure of S. cerevisiae in the ZARM vineyards. The obtained values support the hypothesis that the eight sampled subpopulations come indeed from a larger population.

Molecular relationships between Saccharomyces cerevisiae strains involved in winemaking from Mendoza, Argentina.

Three molecular typing techniques were applied to assess the molecular relationships of Saccharomyces cerevisiae strains isolated from winery equipment, grapes, and spontaneous fermentation in a cellar located in "Zona Alta del Río Mendoza" (Argentina). In addition, commercial Saccharomyces strains widely used in this region were also included. Interdelta PCR typing, mtDNA restriction analysis, and microsatellite (SSR) genotyping were applied. Dendrograms were constructed based on similarity among different patterns of bands. The combination of the three techniques discriminated 34 strains among the 35 isolates. The results of this study show the complex relationships found at molecular level among the isolates that share the same ecological environment, i.e., the winemaking process. With a few exceptions, the yeast isolates were generally clustered in different ways, depending on the typing technique employed. Three clusters were conserved independently of the molecular method applied. These groups of yeasts always clustered together and had high degree of similarity. Furthermore, the dendrograms mostly showed clusters combining strains from winery and fermentation simultaneously. Most of the commercial strains included in this study were clustered separately from the other isolates analyzed, and just a few of them grouped with the strains mainly isolated from spontaneous fermentation. Only one commercial strain was clustered repetitively with a noncommercial strain isolated from spontaneous fermentation in the three dendrograms. On the other hand, this study has demonstrated the importance of selecting an appropriate molecular method according to the main objectives of the research.