What is the optimum post treatment surveillance imaging protocol for low grade appendiceal mucinous neoplasms and pseudomyxoma peritoneii?

Appendiceal mucinous neoplasms are rare and can be associated with the development of disseminated peritoneal disease known as pseudomyxoma peritonei (PMP). Mucinous tumours identified on appendicectomy are therefore followed up to assess for recurrence and the development of PMP. In additional, individuals who initially present with PMP who are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) are followed up to assess for recurrence. However, despite the concerted efforts of multiple expert groups, the optimal imaging follow-up protocol is yet to be established. The purpose of this paper is to review the available evidence for imaging surveillance in these populations to identify the optimum post-resection imaging follow-up protocol.

Two Prediction Error Systems in the Nonlemniscal Inferior Colliculus: "Spectral" and "Nonspectral".

According to the predictive processing framework, perception emerges from the reciprocal exchange of predictions and prediction errors (PEs) between hierarchically organized neural circuits. The nonlemniscal division of the inferior colliculus (IC) is the earliest source of auditory PE signals, but their neuronal generators, properties, and functional relevance have remained mostly undefined. We recorded single-unit mismatch responses to auditory oddball stimulation at different intensities, together with activity evoked by two sequences of alternating tones to control frequency-specific effects. Our results reveal a differential treatment of the unpredictable "many-standards" control and the predictable "cascade" control by lemniscal and nonlemniscal IC neurons that is not present in the auditory thalamus or cortex. Furthermore, we found that frequency response areas of nonlemniscal IC neurons reflect their role in subcortical predictive processing, distinguishing three hierarchical levels: (1) nonlemniscal neurons with sharply tuned receptive fields exhibit mild repetition suppression without signaling PEs, thereby constituting the input level of the local predictive processing circuitry. (2) Neurons with broadly tuned receptive fields form the main, "spectral" PE signaling system, which provides dynamic gain compensation to near-threshold unexpected sounds. This early enhancement of saliency reliant on spectral features was not observed in the auditory thalamus or cortex. (3) Untuned neurons form an accessory, "nonspectral" PE signaling system, which reports all surprising auditory deviances in a robust and consistent manner, resembling nonlemniscal neurons in the auditory cortex. These nonlemniscal IC neurons show unstructured and unstable receptive fields that could result from inhibitory input controlled by corticofugal projections conveying top-down predictions.

Appendiceal Mucinous Neoplasms: From Clinic to Pathology and Prognosis.

Appendiceal mucinous neoplasms have been classified differently over time causing confusion when comparing results between working groups in this field and establishing a prognosis of the disease. A historical perspective of the different classification systems of these tumors is essential for the understanding of the evolution of concepts and histopathological definitions that have led up to the present moment. We carried out a systematic review of the pathological classifications of appendiceal mucinous tumors and how they have included the new criteria resulting from clinical and pathological research. The latest classifications by PSOGI and AJCC 8th edition Cancer Staging have made a great effort to incorporate the new pathological descriptions and develop prognostic groups. The introduction of these new classification systems has posed the challenge of verifying how they adapt to our casuistry and which one defines best the prognosis of our patients. We reclassified our series of patients treated for mucinous appendiceal tumors with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy following the PSOGI and the AJCC 8th edition criteria and concluded that both classifications correspond well with the OS and DFS of these patients, with some advantage relative to the PSOGI classification due to a better histopathological description of the different groups.

Correlation between PSOGI pathological classification and survival outcomes of patients with pseudomyxoma peritonei treated using cytoreductive surgery and HIPEC: national referral centre experience and literature review.

Objectives: The Peritoneal Surface Oncology Group International (PSOGI) consensus subdivided pseudomyxoma peritonei (PMP) into four groups according to histopathological features. The aim of this paper is to report survival outcomes after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) from a national referral centre and to correlate the PSOGI classification with survival. Methods: A retrospective study of a prospectively maintained database was performed. Consecutive patients treated with CRS + HIPEC for PMP of appendiceal origin were included (September-2013 to December-2021). Pathological features of the peritoneal disease were used to classify patients into the four groups proposed by PSOGI. Survival analysis was performed to evaluate the correlation of pathology on overall survival (OS) and disease-free survival (DFS). Results: Overall, 104 patients were identified; 29.6 % were reclassified as acellular mucin (AM), 43.9 % as low-grade mucinous carcinoma peritonei (LGMCP), 22.4 % as high-grade MCP (HGMCP) and 4.1 % as HGMCP with signet ring cells (HGMCP-SRC). Median PCI and rate of optimal cytoreduction were 19 and 82.7 %, respectively. Median OS and DFS were not reached, 5-year OS and DFS were 88.6(SD 0.04) % and 61.6(SD 0.06) %, respectively. Log-Rank test revealed significant differences in terms of OS and DFS across the different histological subgroups (p<0.001 in both cases). However, histology did not retain its significance in the multivariate analysis for OS or DFS (p=0.932 and p=0.872, respectively). Conclusions: Survival outcomes after CRS + HIPEC for PMP are excellent. The PSOGI pathological classification correlates with OS and DFS, but differences were not significant at multivariate analysis when adjusted for other prognostic factors.

Prediction of Acute Myocardial Injury in Noncardiac Surgery in Patients at Risk for Major Adverse Cardiovascular and Cerebrovascular Events: A Multivariable Risk Model.

BACKGROUND: The best use of perioperative cardiac biomarkers assessment is still under discussion. Massive postoperative troponin surveillance can result in untenably high workloads and costs for health care systems and potentially harmful interventions for patients. In a cohort of patients at risk for major adverse cardiovascular and cerebrovascular events (MACCEs), we aimed to (1) determine whether preoperative biomarkers can identify patients at major risk for acute myocardial injury in noncardiac surgery, (2) develop a risk model for acute myocardial injury prediction, and (3) propose an algorithm to optimize postoperative troponin surveillance. METHODS: Prospective, single-center cohort study enrolling consecutive adult patients (≥45 years) at risk for MACCE scheduled for intermediate-to-high-risk noncardiac surgery. Baseline high-sensitivity troponin T (hsTnT) and N-terminal fragment of pro-B-type natriuretic peptide (NT-proBNP), as well as hsTnT on the first 3 postoperative days were obtained. The main outcome was the occurrence of acute myocardial injury. Candidate predictors of acute myocardial injury were baseline concentrations of hsTnT ≥14 ng/L and NT-proBNP ≥300 pg/mL and preoperative and intraoperative variables. A multivariable risk model and a decision curve were constructed. RESULTS: Of 732 patients, 42.1% had elevated hsTnT and 37.3% had elevated NT-proBNP levels at baseline. Acute myocardial injury occurred in 161 patients (22%). Elevated baseline hsTnT, found in 84% of patients with acute myocardial injury, was strongly associated with this outcome: odds ratio (OR), 12.08 (95% confidence interval [CI], 7.78-19.42). Logistic regression identified 6 other independent predictors for acute myocardial injury: age, sex, estimated glomerular filtration rate (eGFR) <45 mL·min -1 ·1.73 m -2 , functional capacity <4 METs or unknown, NT-proBNP ≥300 pg/mL, and estimated intraoperative blood loss. The c -statistic for the risk model was 77% (95% CI, 0.73-0.81). The net benefit of the model began at a risk threshold of 7%. CONCLUSIONS: Baseline determination of cardiac biomarkers in patients at risk for MACCE shortly before intermediate- or high-risk noncardiac surgery helps identify those with the highest risk for acute myocardial injury. A baseline hsTnT ≥14 ng/L indicates the need for postoperative troponin surveillance. In patients with baseline hsTnT <14 ng/L, our 6-predictor model will identify additional patients at risk for acute myocardial injury who may also benefit from postoperative surveillance.

Spontaneous variations in arousal modulate subsequent visual processing and local field potential dynamics in the ferret during quiet wakefulness.

Behavioral states affect neuronal responses throughout the cortex and influence visual processing. Quiet wakefulness (QW) is a behavioral state during which subjects are quiescent but awake and connected to the environment. Here, we examined the effects of pre-stimulus arousal variability on post-stimulus neural activity in the primary visual cortex and posterior parietal cortex in awake ferrets, using pupil diameter as an indicator of arousal. We observed that the power of stimuli-induced alpha (8-12 Hz) decreases when the arousal level increases. The peak of alpha power shifts depending on arousal. High arousal increases inter- and intra-areal coherence. Using a simplified model of laminar circuits, we show that this connectivity pattern is compatible with feedback signals targeting infragranular layers in area posterior parietal cortex and supragranular layers in V1. During high arousal, neurons in V1 displayed higher firing rates at their preferred orientations. Broad-spiking cells in V1 are entrained to high-frequency oscillations (>80 Hz), whereas narrow-spiking neurons are phase-locked to low- (12-18 Hz) and high-frequency (>80 Hz) rhythms. These results indicate that the variability and sensitivity of post-stimulus cortical responses and coherence depend on the pre-stimulus behavioral state and account for the neuronal response variability observed during repeated stimulation.

Which classification system defines best prognosis of mucinous neoplasms of the appendix with peritoneal dissemination: TNM vs PSOGI?

AIMS: Several classification systems are used for pseudomyxoma peritonei. The four-tiered classification system proposed by Peritoneal Surface Oncology Group International (PSOGI) and the two-tiered proposed by the eighth edition of the American Joint Committee on Cancer (AJCC) result from evolution in terminology and pathological insight. The aim is to evaluate the impact of PSOGI and eighth edition of the AJCC classifications on survival. METHODS: Pathological slides were reviewed from a prospectively maintained database including patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for an appendiceal mucinous neoplasm with peritoneal dissemination between January 2009 and December 2019. Patients were reclassified according to PSOGI and AJCC eighth edition criteria. Survival analysis evaluated the impact of each classification system on overall survival (OS) and disease-free survival (DFS) while the concordance-index evaluated their predictive power. RESULTS: 95 patients were identified; 21.1% were reclassified as acellular mucin, 55.8% as low-grade mucinous carcinoma peritonei, 8.4% as high-grade MCP (HGMCP) and 14 as HGMCP with signet ring cells. Median OS was not reached, 5-year OS and DFS were 86.1% and 51.5%, respectively. Multivariate analysis revealed significant associations with OS (PSOGI: HR 10.2, p=0.039; AJCC: HR 7.7, p=0.002) and DFS (PSOGI: HR 12.7, p=0.001; AJCC: HR 3.7, p<0.001). The predictive capacity of both classification systems was unacceptable for OS and DFS (concordance-index values <0.7). CONCLUSIONS: Both classification systems behaved similarly when stratifying our series into prognostic groups. The PSOGI classification provides better histopathological description, but histology alone is insufficient for adequate patient prognostication.

Mortality and incidence of cardiovascular events in patients treated with aspirin and statins at one year after myocardial injury in noncardiac surgery: a prospective observational study.

BACKGROUND: Recommendations on the diagnosis and management of myocardial injury in noncardiac surgery (MINS) show remarkable variability. Mortality reports also vary. We aimed to describe mortality and major adverse cardiovascular and cerebrovascular event (MACCE) rates in patients with silent MINS treated with postoperative aspirin-statin therapy and with cardiology follow-up. METHODS: Prospective descriptive cohort study of patients aged 45 years or older scheduled for noncardiac surgery with high risk for cardiovascular complications from May 2017 to April 2019. Aspirin-statin therapy and cardiology follow-up were prescribed for patients with silent (asymptomatic) MINS. The primary outcome was one-year mortality in patients with silent MINS, diagnosed by troponin concentration. Secondary outcomes were mortality in MINS patients with perioperative myocardial infarction (PMI) or chronic myocardial injury (CMI) and MACCE. RESULTS: We identified 766 eligible patients and enrolled 747. MINS occurred in 166 patients (22.2%); 151 (91%) had silent MINS and 15 (9%) had PMI. Thirty-one patients (4.1%) had CMI. One-year mortality was higher in patients with silent MINS (22.5%) than in patients with no MINS (7.8%) (P<0.001). One-year mortality rates in MINS patients with PMI or CMI were 27 and 19%, respectively. MACCE were more frequent in patients with silent MINS at 30 days and one year (18 and 25%) than in patients with no MINS (6 and 12%, respectively). CONCLUSIONS: Rates of mortality and MACCE in patients with silent MINS were high despite aspirin-statin therapy and cardiology follow-up. Further prospective research is needed to assess new postoperative care protocols that might effectively improve outcomes.

Vitamin D Deficiency Reduces Postthyroidectomy Protracted Hypoparathyroidism Risk. Is Gland Preconditioning Possible?

Context: Hypoparathyroidism is the most frequent complication after total thyroidectomy (PT-hypoPTH). After 1 year, most patients recover parathyroid function; however, the implicated physiologic dynamics remain unknown. Vitamin D deficiency (VDD) is the main cause of secondary hyperparathyroidism. Whether this compensatory hyperparathyroidism could influence parathyroid function recovery (PFR) in the setting of PT-hypoPTH has not been studied. Objective: This work aimed to evaluate the effect of preoperative VDD on PFR. Methods: A retrospective study was conducted with a prospectively maintained database including patients undergoing a total thyroidectomy between May 2014 and June 2019. Preoperative vitamin D (25(OH)D) less than 20 mg/mL was defined as VDD. Intact PTH less than 14 pg/mL on postoperative day 1 was defined as PT-hypoPTH. Transient PT-hypoPTH displayed PFR within the first year (early recovery: < 30 days; protracted recovery: > 30 days) whereas definite PT-hypoPTH did not. Survival analysis evaluated the effect of preoperative VDD on PFR, and a binary logistic regression model identified associated factors. Results: A total of 397 patients were identified. The observed rates of transient, protracted, and definite PT-hypoPTH were 32.9%, 15.1%, and 5.2%, respectively. Rates of VDD were higher in the early-recovery PT-hypoPTH group (55.2% vs 31.5%; P = .01). Preoperative VDD was associated with faster PFR (19 vs 35 days; P = .03) and behaved as a protective factor for protracted PT-hypoPTH (odds ratio 0.47; 95% CI, 0.25-0.881; P = .016) in the multivariable analysis. Conclusion: Preoperative VDD could act as a preconditioning factor of the parathyroid glands prior to the surgical aggression exerted against them during surgery aiding PFR. Basic research studies and prospective clinical trials are needed to explain the underlying physiological mechanisms and to provide further evidence to improve clinical management.

Complications and Mortality Rate of Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy: Italian Peritoneal Surface Malignancies Oncoteam Results Analysis.

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy may significantly improve survival for selected patients with peritoneal surface malignancies, but it has always been criticized due to the high incidence of postoperative morbidity and mortality. METHODS: Data were collected from nine Italian centers with peritoneal surface malignancies expertise within a collaborative group of the Italian Society of Surgical Oncology. Complications and mortality rates were recorded, and multivariate Cox analysis was used to identify risk factors. RESULTS: The study included 2576 patients. The procedure was mostly performed for ovarian (27.4%) and colon cancer (22.4%). The median peritoneal cancer index was 13. Overall postoperative morbidity and mortality rates were 34% and 1.6%. A total of 232 (9%) patients required surgical reoperation. Multivariate regression logistic analysis identified the type of perfusion (p ≤ 0.0001), body mass index (p ≤ 0.0001), number of resections (p ≤ 0.0001) and colorectal resections (p ≤ 0.0001) as the strongest predictors of complications, whereas the number of resections (p ≤ 0.0001) and age (p = 0.01) were the strongest predictors of mortality. CONCLUSIONS: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is a valuable option of treatment for selected patients with peritoneal carcinomatosis providing low postoperative morbidity and mortality rates, if performed in high-volume specialized centers.

Relationship between the anatomical location and the selective non-operative management of penetrating stab wounds in the abdomen.

INTRODUCTION: The relationship between the anatomical location of penetrating abdominal stab wounds (SW) and the rate of selective non-operative management (SNOM) based on that location is scarcely reflected in the specialized literature. Our main objective has been to assess this rate based on the anatomical location, and our results. METHODS: Retrospective review of a prospective registry of abdominal trauma from April 1993 to June 2020. The two study groups considered were the Operative Management (OM), and the SNOM, including in this one the use of diagnostic laparoscopy. Penetrating SWs in the abdomen were classified according to anatomical location. RESULTS: We identified 259 patients who fulfilled the inclusion criteria. SNOM was applied in 31% of the patients with a success rate of 96%, and it was more frequent in the lumbar, flank, and thoraco-abdominal regions; within the anterior abdomen it was more applicable in the RH, followed by the LH and epigastrium, respectively. An unnecessary laparotomy was done in 21% of patients, with the highest number in the epigastrium. Taking into account the unnecessary laparotomies and the rates of successful SNOM, 70.5% of lumbar, 66.5% of epigastric, 62% of flank, and 59% of RH penetrating SW could have been managed without a laparotomy. CONCLUSIONS: SNOM of penetrating SW in the abdomen has been safer and more applicable in those located in the lumbar, flank, epigastric, and RH regions.

Relación entre la localización anatómica y el manejo selectivo no operatorio de las heridas por arma blanca penetrantes en abdomen / Relationship between the anatomical location and the selective non-operative management of penetrating stab wounds in the abdomen

Introducción: La localización anatómica de las heridas por arma blanca (HAB) penetrantes en abdomen y su relación con el manejo selectivo no operatorio (MSNO) tiene escaso reflejo en la literatura especializada. Nuestro objetivo principal ha sido valorar la tasa de MSNO en función de esa localización anatómica, y sus resultados. Métodos: Revisión retrospectiva del registro prospectivo de trauma abdominal desde abril de 1993 hasta junio de 2020. Los dos grupos a estudio fueron manejo operatorio (MO) y MSNO, incluyendo en este último grupo el uso de laparoscopias exploradoras como método diagnóstico. Se clasificaron las HAB penetrantes en abdomen en función de su localización anatómica. Resultados: Identificamos 259 pacientes que cumplían los criterios de inclusión. El MSNO se aplicó en el 31% de los pacientes, con una tasa de éxito del 96,5%. En las HAB de las regiones lumbares, flancos y toracoabdominales fue donde se optó más frecuentemente por este manejo; y en el abdomen anterior fue más aplicable en el hipocondrio derecho (HD), seguido del hipocondrio izquierdo (HI) y epigastrio. Se realizó una laparotomía innecesaria en el 21%, con la cifra más alta en el epigastrio. Teniendo en cuenta los porcentajes de MSNO y laparotomías evitables en cada región, el 70,5% de las HAB lumbares, el 66,5% de las epigástricas, el 62% de flancos y el 59% de HD se podrían haber manejado con éxito sin laparotomía. Conclusiones: El MSNO de las HAB penetrantes en abdomen ha resultado más seguro y aplicable en las localizadas en las regiones lumbares, flancos, epigastrio e HD (AU)

Introduction: The relationship between the anatomical location of penetrating abdominal stab wounds (SW) and the rate of selective non-operative management (SNOM) based on that location is scarcely reflected in the specialized literature. Our main objective has been to assess this rate based on the anatomical location, and our results. Methods: Retrospective review of a prospective registry of abdominal trauma from April 1993 to June 2020. The two study groups considered were the Operative Management (OM), and the SNOM, including in this one the use of diagnostic laparoscopy. Penetrating SWs in the abdomen were classified according to anatomical location. Results: We identified 259 patients who fulfilled the inclusion criteria. SNOM was applied in 31% of the patients with a success rate of 96%, and it was more frequent in the lumbar, flank, and thoraco-abdominal regions; within the anterior abdomen it was more applicable in the RUQ, followed by the LUQ and epigastrium, respectively. An unnecessary laparotomy was done in 21% of patients, with the highest number in the epigastrium. Taking into account the unnecessary laparotomies and the rates of successful SNOM, 70,5% of lumbar, el 66,5% of epigastric, 62% of flank, and 59% of RUQ penetrating SWs could have been managed without a laparotomy. Conclusions: SNOM of penetrating SWs in the abdomen has been safer and more applicable in those located in the lumbar, flank, epigastric, and RUQ regions (AU)

Early procalcitonin to predict mortality in critically ill COVID-19 patients: a multicentric cohort study.

BACKGROUND: High levels of procalcitonin (PCT) have been associated with a higher risk of mortality in COVID-19 patients. We explored the prognostic role of early PCT assessment in critically ill COVID-19 patients and whether PCT predictive performance would be influenced by immunosuppression. METHODS: Retrospective multicentric analysis of prospective collected data in COVID-19 patients consecutively admitted to 36 intensive care units (ICUs) in Spain and Andorra from March to June 2020. Adult (>18 years) patients with confirmed COVID-19 and available PCT values (<72 hours from ICU admission) were included. Patients were considered as "no immunosuppression" (NI), "chronic immunosuppression" (CI) and "acute immunosuppression" (AIT if only tocilizumab; AIS if only steroids, AITS if both). The primary outcome was the ability of PCT to predict ICU mortality. RESULTS: Of the 1079 eligible patients, 777 patients were included in the analysis. Mortality occurred in 227 (28%) patients. In the NI group 144 (19%) patients were included, 67 (9%) in the CI group, 66 (8%) in the AIT group, 262 (34%) in the AIS group and 238 (31%) in the AITS group; PCT was significantly higher in non-survivors when compared with survivors (0.64 [0.17-1.44] vs. 0.23 [0.11-0.60] ng/mL; P<0.01); however, in the multivariable analysis, PCT values was not independently associated with ICU mortality. PCT values and ICU mortality were significantly higher in patients in the NI and CI groups. CONCLUSIONS: PCT values are not independent predictors of ICU mortality in COVID-19 patients. Acute immunosuppression significantly reduced PCT values, although not influencing its predictive value.

Systemic metastases from low-grade and high-grade pseudomyxoma peritonei: Treatments and outcomes.

BACKGROUND: The metastasizing potential of pseudomyxoma peritonei (PMP) is largely unknown. We assessed incidence, impact on prognosis, treatments, and outcomes of systemic metastases after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). METHODS: A prospective database of 327 patients undergoing CRS/HIPEC for PMP of appendiceal origin was reviewed. PMP was graded according to the Peritoneal Surface Oncology Group International (PSOGI) classification. Haematogenous metastases, and non-regional lymph-node involvement were considered as systemic metastases. RESULTS: After a median follow-up of 74.8 months (95% confidence interval [CI] = 68.0-94.8), systemic metastases occurred in 21 patients. Eleven patients were affected by low-grade PMP, and ten by high-grade PMP. Metastatic disease involved the lung (n = 12), bone (n = 1), liver (n = 4), distant nodes (n = 3), both lung and distant nodes (n = 1). Systemic metastases independently correlated with PSOGI histological subtypes (P = 0.001), and incomplete cytoreduction (P = 0.026). Median OS was 139.0 months (95%CI = 56.6-161.9) for patients who experienced systemic metastases, and 213.8 months (95%CI = 148.7-not reached) for those who did not (P = 0.159). Eight of eleven patients who had curative-intent surgery are presently alive at a median of 52.5 months (range 2.0-112.7). Seven are disease-free at a median of 27.4 months (range 2.0-110.4). At multivariate analysis, PSOGI histological subtypes (P = 0.001), completeness of cytoreduction (P = 0.001), and preoperative systemic chemotherapy (P = 0.020) correlated with poorer survival. Systemic metastases did not (P = 0.861). CONCLUSIONS: After CRS/HIPEC, systemic metastases occur in a small but clinically relevant number of patients, and the risk increases with incomplete cytoreduction and aggressive histology. In selected patients, surgical resection of metastatic disease can result in long survival.

Relevance of pneumoperitoneum in the conservative approach to complicated acute diverticulitis. A retrospective study identifying risk factors associated with treatment failure.

BACKGROUND: The aim of this study is to evaluate the relevance of pneumoperitoneum on the success rate of non-operative management (NOM) of patients with complicated acute diverticulitis (AD), and the risk factors associated with failure. METHODS: Observational retrospective cohort study of patients attended at the emergency department for AD from January 2015-August 2019. Patient demographics, blood tests, radiological data and initial treatment strategies were registered. NOM, based on intravenous antibiotics (ATB) and bowel rest, was defined as unsuccessful when emergency surgery (ES) and/or infection-related death took place. Patients initially treated with ES were excluded. Analysis was done with the IBM SPSS statistics 23.0.0.2 software. RESULTS: According to modified Hinchey and WSES criteria, 99 (12%) of 826 AD episodes were complicated, with pneumoperitoneum on the CT scan in 89 (90.5%). NOM was undertaken in 93 (94%) cases, with a 91.5% success rate. Multivariate analysis revealed ASA class III-IV, and the presence of fluid collections >3 cm in diameter, but not distant free air, to be associated with NOM failure. However, the success rate of NOM was significantly higher in patients with pericolic pneumoperitoneum (98.5%) than in those with distant free air (80%) (P=0.02). Risk factors of NOM failure were an advanced age, high CRP and WBC values, and the presence of free fluid in >2 abdominal quadrants. CONCLUSIONS: NOM in hemodynamically stable patients with complicated AD is a safe and feasible approach, even in the context of distant free air. Nevertheless, patients with isolated pericolic air did better in our series.

The posterior auditory field is the chief generator of prediction error signals in the auditory cortex.

The auditory cortex (AC) encompasses distinct fields subserving partly different aspects of sound processing. One essential function of the AC is the detection of unpredicted sounds, as revealed by differential neural activity to predictable and unpredictable sounds. According to the predictive coding framework, this effect can be explained by repetition suppression and/or prediction error signaling. The present study investigates functional specialization of the rat AC fields in repetition suppression and prediction error by combining a tone frequency oddball paradigm (involving high-probable standard and low-probable deviant tones) with two different control sequences (many-standards and cascade). Tones in the control sequences were comparable to deviant events with respect to neural adaptation but were not violating a regularity. Therefore, a difference in the neural activity between deviant and control tones indicates a prediction error effect, whereas a difference between control and standard tones indicates a repetition suppression effect. Single-unit recordings revealed by far the largest prediction error effects for the posterior auditory field, while the primary auditory cortex, the anterior auditory field, the ventral auditory field, and the suprarhinal auditory field were dominated by repetition suppression effects. Statistically significant repetition suppression effects occurred in all AC fields, whereas prediction error effects were less robust in the primary auditory cortex and the anterior auditory field. Results indicate that the non-lemniscal, posterior auditory field is more engaged in context-dependent processing underlying deviance-detection than the other AC fields, which are more sensitive to stimulus-dependent effects underlying differential degrees of neural adaptation.

Advances in neoadjuvant therapy for resectable pancreatic cancer over the past two decades.

In the last two decades, pancreatic cancer has been undergoing important changes in its perioperative management due to the great interest in multidisciplinary management and preoperative multimodal therapy, which in numerous studies have shown promising clinical results. Although the standard of treatment for resectable pancreatic ductal adenocarcinoma (PDAC) today is surgery followed by adjuvant therapy, as it is a biologically aggressive disease, even with complete resection, it has high rates of local and distant relapse. Several retrospective and prospective phase I/II studies have opened the window for neoadjuvant therapy with chemotherapy (CT), chemoradiotherapy (CRT), or both, as an alternative treatment for resectable pancreatic cancer, with promising results. Neoadjuvant therapy could has some advantages, including early administration of systemic treatment, in vivo assessment of response to treatment, increase resectability rate in borderline patients, increase resection rate with negative margin and survival benefit. While it seems clear that even potentially resectable disease would benefit from preoperative multimodal therapy, the optimal neoadjuvant therapeutic strategy is still controversial and currently there are only recommendations for neoadjuvant treatment, in clinical guidelines such as the NCCN and ESMO, for borderline and/or locally advanced PDAC. This review provides an overview of recent studies available and how they relate to systemic treatment of resectable PDAC in the neoadjuvant setting.

Relationship between the anatomical location and the selective non-operative management of penetrating stab wounds in the abdomen. / Relación entre la localización anatómica y el manejo selectivo no operatorio de las heridas por arma blanca penetrantes en abdomen.

INTRODUCTION: The relationship between the anatomical location of penetrating abdominal stab wounds (SW) and the rate of selective non-operative management (SNOM) based on that location is scarcely reflected in the specialized literature. Our main objective has been to assess this rate based on the anatomical location, and our results. METHODS: Retrospective review of a prospective registry of abdominal trauma from April 1993 to June 2020. The two study groups considered were the Operative Management (OM), and the SNOM, including in this one the use of diagnostic laparoscopy. Penetrating SWs in the abdomen were classified according to anatomical location. RESULTS: We identified 259 patients who fulfilled the inclusion criteria. SNOM was applied in 31% of the patients with a success rate of 96%, and it was more frequent in the lumbar, flank, and thoraco-abdominal regions; within the anterior abdomen it was more applicable in the RUQ, followed by the LUQ and epigastrium, respectively. An unnecessary laparotomy was done in 21% of patients, with the highest number in the epigastrium. Taking into account the unnecessary laparotomies and the rates of successful SNOM, 70,5% of lumbar, el 66,5% of epigastric, 62% of flank, and 59% of RUQ penetrating SWs could have been managed without a laparotomy. CONCLUSIONS: SNOM of penetrating SWs in the abdomen has been safer and more applicable in those located in the lumbar, flank, epigastric, and RUQ regions.

In vivo whole-cell recordings of stimulus-specific adaptation in the inferior colliculus.

The inferior colliculus is an auditory structure where inputs from multiple lower centers converge, allowing the emergence of complex coding properties of auditory information such as stimulus-specific adaptation. Stimulus-specific adaptation is the adaptation of neuronal responses to a specific repeated stimulus, which does not entirely generalize to other new stimuli. This phenomenon provides a mechanism to emphasize saliency and potentially informative sensory inputs. Stimulus-specific adaptation has been traditionally studied analyzing the somatic spiking output. However, studies that correlate within the same inferior colliculus neurons their intrinsic properties, subthreshold responses and the level of acoustic stimulus-specific adaptation are still pending. For this, we recorded in vivo whole-cell patch-clamp neurons in the mouse inferior colliculus while stimulating with current injections or the classic auditory oddball paradigm. Our data based on cases of ten neuron, suggest that although passive properties were similar, intrinsic properties differed between adapting and non-adapting neurons. Non-adapting neurons showed a sustained-regular firing pattern that corresponded to central nucleus neurons and adapting neurons at the inferior colliculus cortices showed variable firing patterns. Our current results suggest that synaptic stimulus-specific adaptation was variable and could not be used to predict the presence of spiking stimulus-specific adaptation. We also observed a small trend towards hyperpolarized membrane potentials in adapting neurons and increased synaptic inhibition with consecutive stimulus repetitions in all neurons. This finding indicates a more simple type of adaptation, potentially related to potassium conductances. Hence, these data represent a modest first step in the intracellular study of stimulus-specific adaptation in inferior colliculus neurons in vivo that will need to be expanded with pharmacological manipulations to disentangle specific ionic channels participation.