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1.
Hum Pathol ; 152: 105640, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128557

RESUMO

The impact of special histological types (ST) in triple-negative breast cancer (TNBC) and its association with overall outcome has gained increasing relevance as survival has been linked to specific histological TNBC subtypes. We evaluated the clinicopathological and survival data of 598 patients with 613 TNBCs, including 464 TNBCs of no special type (NST) and 149 TNBCs ST (low-grade, n = 12, 8.1%; high-grade, n = 112, 75.2%; apocrine and androgen receptor-positive [APO AR], n = 25, 16.8%). Patients with low-grade TNBC ST and TNBC ST APO AR were significantly older (P < 0.001) and had a lower Ki67 index (P < 0.001) than those with TNBC NST. Patients with high-grade TNBC ST were significantly older (P = 0.006) and had poorer pathological responses to neoadjuvant chemotherapy (NAC) (P < 0.001) than those with TNBC NST. Significant survival differences were observed between low-grade TNBC ST, TNBC ST APO AR, high-grade TNBC ST, and TNBC NST in the entire study group (DFS, P = 0.002; DDFS, P = 0.001) and in the non-NAC subgroup (OS, P = 0.034; DFS, P = 0.001; DDFS, P < 0.001). Patients with low-grade TNBC ST had the best survival outcomes. Patients with high-grade TNBC ST showed significantly worse outcomes than those with TNBC NST (entire study group: OS, P = 0.049; DFS, P < 0.001; DDFS, P = 0.001; non-NAC subgroup: OS, P = 0.014; DFS, P < 0.001; DDFS, P < 0.001). We conclude that prognostic stratification of TNBC ST is ultimately important for optimizing the therapeutic management of patients with these rare tumor entities.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/terapia , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Prognóstico , Biomarcadores Tumorais/análise , Terapia Neoadjuvante , Gradação de Tumores , Receptores Androgênicos/análise , Intervalo Livre de Doença , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante
2.
Environ Sci Technol ; 58(26): 11292-11300, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38888518

RESUMO

Aluminum (Al) is the most abundant metal in the earth's crust, and humans are exposed to Al through sources like food, cosmetics, and medication. So far, no comprehensive data on the Al distribution between and within human tissues were reported. We measured Al concentrations in 24 different tissue types of 8 autopsied patients using ICP-MS/MS (inductively coupled plasma-tandem mass spectrometry) under cleanroom conditions and found surprisingly high concentrations in both the upper and inferior lobes of the lung and hilar lymph nodes. Al/Si ratios in lung and hilar lymph node samples of 12 additional patients were similar to the ratios reported in urban fine dust. Histological analyses using lumogallion staining showed Al in lung erythrocytes and macrophages, indicating the uptake of airborne Al in the bloodstream. Furthermore, Al was continuously found in PM2.5 and PM10 fine dust particles over 7 years in Upper Austria, Austria. According to our findings, air pollution needs to be reconsidered as a major Al source for humans and the environment.


Assuntos
Alumínio , Pulmão , Linfonodos , Humanos , Pulmão/metabolismo , Exposição Ambiental , Poluentes Atmosféricos , Poeira , Masculino , Feminino , Material Particulado , Áustria , Pessoa de Meia-Idade
4.
BMC Surg ; 24(1): 121, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658891

RESUMO

BACKGROUND: Nonoperative management of uncomplicated appendicitis is currently being promoted as treatment option, albeit 0.7-2.5% of appendectomies performed due to suspected acute appendicitis show histologically malignant findings. The purpose of this study was to investigate the incidence of neoplasm and malignancy of the appendix in patients presenting with suspected acute appendicitis in real world setting. METHODS: This is a retrospective single-centre investigation of 457 patients undergoing appendectomy between the years 2017-2020. The patients' demographics, symptoms and diagnosis, intraoperative findings, and histopathological results were analysed. RESULTS: In 3.7% (n = 17) histological analysis revealed neoplasms or malignancies. Median age was 48 years (20-90 years), without sex predominance. Leukocytes (11.3 ± 3.7 G/l) and C-reactive protein (54.2 ± 69.0 mg/l) were elevated. Histological analysis revealed low-grade mucinous appendiceal neoplasia (n = 3), sessile serrated adenoma of the appendix (n = 3), neuroendocrine tumours (n = 7), appendiceal adenocarcinoma of intestinal type (n = 3), and goblet cell carcinoma (n = 1). Additional treatment varied between no treatment or follow-up due to early tumour stage (n = 4), follow-up care (n = 3), additional surgical treatment (n = 8), or best supportive care (n = 2). CONCLUSIONS: Preoperative diagnosis of appendiceal tumours is difficult. Nonoperative management of patients with acute, uncomplicated appendicitis potentially prevents the correct diagnosis of malignant appendiceal pathologies. Therefore, close follow-up or surgical removal of the appendix is mandatory.


Assuntos
Apendicectomia , Neoplasias do Apêndice , Apendicite , Humanos , Neoplasias do Apêndice/epidemiologia , Neoplasias do Apêndice/diagnóstico , Neoplasias do Apêndice/patologia , Neoplasias do Apêndice/terapia , Neoplasias do Apêndice/cirurgia , Apendicite/epidemiologia , Apendicite/cirurgia , Apendicite/diagnóstico , Apendicite/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos , Masculino , Feminino , Adulto , Idoso , Apendicectomia/estatística & dados numéricos , Incidência , Idoso de 80 Anos ou mais , Adulto Jovem , Doença Aguda
5.
Gastric Cancer ; 27(4): 649-671, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38634954

RESUMO

BACKGROUND: Many gastric cancer patients in Western countries are diagnosed as metastatic with a median overall survival of less than twelve months using standard chemotherapy. Innovative treatments, like targeted therapy or immunotherapy, have recently proved to ameliorate prognosis, but a general agreement on managing oligometastatic disease has yet to be achieved. An international multi-disciplinary workshop was held in Bertinoro, Italy, in November 2022 to verify whether achieving a consensus on at least some topics was possible. METHODS: A two-round Delphi process was carried out, where participants were asked to answer 32 multiple-choice questions about CT, laparoscopic staging and biomarkers, systemic treatment for different localization, role and indication of palliative care. Consensus was established with at least a 67% agreement. RESULTS: The assembly agreed to define oligometastases as a "dynamic" disease which either regresses or remains stable in response to systemic treatment. In addition, the definition of oligometastases was restricted to the following sites: para-aortic nodal stations, liver, lung, and peritoneum, excluding bones. In detail, the following conditions should be considered as oligometastases: involvement of para-aortic stations, in particular 16a2 or 16b1; up to three technically resectable liver metastases; three unilateral or two bilateral lung metastases; peritoneal carcinomatosis with PCI ≤ 6. No consensus was achieved on how to classify positive cytology, which was considered as oligometastatic by 55% of participants only if converted to negative after chemotherapy. CONCLUSION: As assessed at the time of diagnosis, surgical treatment of oligometastases should aim at R0 curativity on the entire disease volume, including both the primary tumor and its metastases. Conversion surgery was defined as surgery on the residual volume of disease, which was initially not resectable for technical and/or oncological reasons but nevertheless responded to first-line treatment.


Assuntos
Consenso , Técnica Delphi , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/terapia , Metástase Neoplásica , Itália , Estadiamento de Neoplasias
6.
Nat Commun ; 14(1): 7470, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978298

RESUMO

Darier disease (DD) is a rare, inherited multi-organ disorder associated with mutations in the ATP2A2 gene. DD patients often have skin involvement characterized by malodorous, inflamed skin and recurrent, severe infections. Therapeutic options are limited and inadequate for the long-term management of this chronic disease. The aim of this study was to characterize the cutaneous immune infiltrate in DD skin lesions in detail and to identify new therapeutic targets. Using gene and protein expression profiling assays including scRNA sequencing, we demonstrate enhanced expression of Th17-related genes and cytokines and increased numbers of Th17 cells in six DD patients. We provide evidence that targeting the IL-17/IL-23 axis in a case series of three DD patients with monoclonal antibodies is efficacious with significant clinical improvement. As DD is a chronic, relapsing disease, our findings might pave the way toward additional options for the long-term management of skin inflammation in patients with DD.


Assuntos
Doença de Darier , Humanos , Doença de Darier/genética , Doença de Darier/metabolismo , Doença de Darier/patologia , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-23/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Pele/patologia , Células Th17/metabolismo
7.
Virchows Arch ; 483(5): 611-619, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37653260

RESUMO

Minimally invasive autopsies (MIAs) allow the collection of tissue samples for diagnostic and research purposes in special situations, e.g., when there is a high risk of infection which is the case in the context of COVID-19 or restrictions due to legal or personal reasons. We performed MIA to analyze lung tissue from 92 COVID-19 patients (mean age 78 years; range 48-98; 35 women, 57 men), representing 44% of all patients who died from the disease between October 2020 and April 2021. An intercostal approach was used with removal of a 5-cm rib section followed by manual collection of four lung tissue samples (5-8 cm in size). Diffuse alveolar damage (DAD) was found in 89 (97%) patients at various stages. Exudative DAD (eDAD) predominated in 18 (20%) patients, proliferative DAD (pDAD) in 43 (47%) patients, and mixed DAD (mDAD) in 31 (34%) patients. There were no significant differences in the predominant DAD pattern between tissue samples from the same patient. Additional purulent components were present in 46 (50%) cases. Fungi were detected in 11 (12%) patients. The pDAD pattern was associated with longer hospital stay including intensive care unit (p=0.026 and p<0.001) and younger age (p=0.019). Positive bronchoalveolar lavage and blood cultures were observed more frequently in pDAD patterns (p<0.001; p=0.018). In contrast, there was no significant association between intravital positive microbiological results and superimposed bronchopneumonia or fungal infection at autopsy. Having demonstrated the characteristic lung changes in a large longitudinal autopsy series, we conclude that the presented MIA approach can be considered a reliable and safe method for performing post mortem lung diagnostics in COVID-19 and other high-risk situations. The lack of correlation between histological changes indicative of bacterial or fungal superinfection and microbiology could have clinical implications for disease and treatment surveillance.


Assuntos
COVID-19 , Masculino , Humanos , Feminino , Idoso , COVID-19/patologia , Autopsia/métodos , Pulmão/patologia
8.
Cancer Cell ; 41(9): 1650-1661.e4, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37652006

RESUMO

Deep learning (DL) can accelerate the prediction of prognostic biomarkers from routine pathology slides in colorectal cancer (CRC). However, current approaches rely on convolutional neural networks (CNNs) and have mostly been validated on small patient cohorts. Here, we develop a new transformer-based pipeline for end-to-end biomarker prediction from pathology slides by combining a pre-trained transformer encoder with a transformer network for patch aggregation. Our transformer-based approach substantially improves the performance, generalizability, data efficiency, and interpretability as compared with current state-of-the-art algorithms. After training and evaluating on a large multicenter cohort of over 13,000 patients from 16 colorectal cancer cohorts, we achieve a sensitivity of 0.99 with a negative predictive value of over 0.99 for prediction of microsatellite instability (MSI) on surgical resection specimens. We demonstrate that resection specimen-only training reaches clinical-grade performance on endoscopic biopsy tissue, solving a long-standing diagnostic problem.


Assuntos
Algoritmos , Neoplasias Colorretais , Humanos , Biomarcadores , Biópsia , Instabilidade de Microssatélites , Neoplasias Colorretais/genética
9.
J Cancer Res Clin Oncol ; 149(14): 13345-13352, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37491637

RESUMO

BACKGROUND: Combination of immunotherapy and chemotherapy is recommended for first line treatment of gastric adenocarcinoma (GC) patients with locally advanced unresectable disease or metastatic disease. However, data regarding the concordance rate between PD-L1 combined positive score (CPS) in primary GC and matched regional lymph node metastasis (LNmet) or matched distant metastasis (Dmet) is limited. METHODS: Tissue microarray sections from primary resected GC, LNmet and Dmet were immunohistochemically stained with anti-PD-L1 (clone SP263). PD-L1 expression was scored separately in tumour cells and immune cells and compared between matched primary GC, LNmet and/or Dmet. CPS was calculated and results for CPS cut-offs 1 and 5 were compared between matched samples. RESULTS: 275 PD-L1 stained GC were analysed. 189 primary GC had matched LNmet. CPS cut-off 1 concordance rate between primary GC and LNmet was 77%. 23 primary GC had matched Dmet but no matched LNmet, CPS cut-off 1 concordance rate was 70%. 63 primary GC had both matched LNmet and matched Dmet, CPS cut-off 1 concordance rate of 67%. CPS cut-off 5 results were similar. The proportion of PD-L1 positive tumour cells increased from primary GC (26%) to LNmet (42%) and was highest in Dmet (75%). CONCLUSION: Our study showed up to 33% discordance of PD-L1 CPS between primary GC and LNmet and/or Dmet suggesting that multiple biopsies of primary GC and metastatic sites might need to be tested before considering treatment options. Moreover, this is the first study that seems to suggest that tumour cells acquire PD-L1 expression during disease progression.

10.
Br J Cancer ; 128(12): 2318-2325, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37029200

RESUMO

BACKGROUND: Only a subset of gastric cancer (GC) patients with stage II-III benefits from chemotherapy after surgery. Tumour infiltrating lymphocytes per area (TIL density) has been suggested as a potential predictive biomarker of chemotherapy benefit. METHODS: We quantified TIL density in digital images of haematoxylin-eosin (HE) stained tissue using deep learning in 307 GC patients of the Yonsei Cancer Center (YCC) (193 surgery+adjuvant chemotherapy [S + C], 114 surgery alone [S]) and 629 CLASSIC trial GC patients (325 S + C and 304 S). The relationship between TIL density, disease-free survival (DFS) and clinicopathological variables was analysed. RESULTS: YCC S patients and CLASSIC S patients with high TIL density had longer DFS than S patients with low TIL density (P = 0.007 and P = 0.013, respectively). Furthermore, CLASSIC patients with low TIL density had longer DFS if treated with S + C compared to S (P = 0.003). No significant relationship of TIL density with other clinicopathological variables was found. CONCLUSION: This is the first study to suggest TIL density automatically quantified in routine HE stained tissue sections as a novel, clinically useful biomarker to identify stage II-III GC patients deriving benefit from adjuvant chemotherapy. Validation of our results in a prospective study is warranted.


Assuntos
Linfócitos do Interstício Tumoral , Neoplasias Gástricas , Humanos , Biomarcadores , Quimioterapia Adjuvante , Linfócitos do Interstício Tumoral/patologia , Prognóstico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
11.
Br J Cancer ; 128(11): 2036-2043, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36966233

RESUMO

BACKGROUND: No definitive largescale data exist evaluating the role of pathologically defined regression changes within the primary tumour and lymph nodes (LN) of resected oesophagogastric (OG) adenocarcinoma following neoadjuvant chemotherapy and the impact on survival. METHODS: Data and samples from two large prospective randomised trials (UK MRC OE05 and ST03) were pooled. Stained slides were available for central pathology review from 1619 patients. Mandard tumour regression grade (TRG) and regression of tumour within LNs (LNR: scored as present/absent) were assessed and correlated with overall survival (OS) using a Cox regression model. An exploratory analysis to define subgroups with distinct prognoses was conducted using a classification and regression tree (CART) analysis. RESULTS: Neither trial demonstrated a relationship between TRG score and the presence or absence of LNR. In univariable analysis, lower TRG, lower ypN stage, lower ypT stage, presence of LNR, presence of well/moderate tumour differentiation, and absence of tumour at resection margin were all associated with better OS. However, the multivariable analysis demonstrated that only ypN, ypT, grade of differentiation and resection margin (R0) were independent indicators of prognosis. Exploratory CART analysis identified six subgroups with 3-year OS ranging from 83% to 22%; with ypN stage being the most important single prognostic variable. CONCLUSIONS: Pathological LN stage within the resection specimen was the single most important determiner of survival. Our results suggest that the assessment of regression changes within the primary tumour or LNs may not be necessary to define the prognosis further.


Assuntos
Adenocarcinoma , Margens de Excisão , Humanos , Estudos Prospectivos , Linfonodos/patologia , Prognóstico , Adenocarcinoma/patologia , Terapia Neoadjuvante , Estadiamento de Neoplasias , Estudos Retrospectivos
12.
Gastric Cancer ; 26(2): 264-274, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36264524

RESUMO

BACKGROUND: Computational pathology uses deep learning (DL) to extract biomarkers from routine pathology slides. Large multicentric datasets improve performance, but such datasets are scarce for gastric cancer. This limitation could be overcome by Swarm Learning (SL). METHODS: Here, we report the results of a multicentric retrospective study of SL for prediction of molecular biomarkers in gastric cancer. We collected tissue samples with known microsatellite instability (MSI) and Epstein-Barr Virus (EBV) status from four patient cohorts from Switzerland, Germany, the UK and the USA, storing each dataset on a physically separate computer. RESULTS: On an external validation cohort, the SL-based classifier reached an area under the receiver operating curve (AUROC) of 0.8092 (± 0.0132) for MSI prediction and 0.8372 (± 0.0179) for EBV prediction. The centralized model, which was trained on all datasets on a single computer, reached a similar performance. CONCLUSIONS: Our findings demonstrate the feasibility of SL-based molecular biomarkers in gastric cancer. In the future, SL could be used for collaborative training and, thus, improve the performance of these biomarkers. This may ultimately result in clinical-grade performance and generalizability.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Instabilidade de Microssatélites , Biomarcadores Tumorais/genética
13.
Updates Surg ; 75(2): 395-402, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36001283

RESUMO

Classification of adenocarcinomas (AC) arising around or within the gastroesophageal junction (GEJ) is hampered by major morphologic and phenotypic overlaps. We reviewed the surgical pathology of esophagectomy specimens of 115 primary resected AC of the esophagus as defined by the 5th edition of the WHO classification regarding the anatomical site of the tumor, with corresponding categorization according to the Siewert AEG Classification and the preceding 4th edition of the WHO (discriminating esophageal adenocarcinomas/EAC and adenocarcinomas of the gastroesophageal junction/AdGEJ), and further histology findings. In addition, immunohistochemistry (IHC) for CDX2, CK7, CK20, MUC2, MUC5AC and MUC6 was performed. Sixty-eight cases were Siewert AEG type I and 47 cases Siewert AEG type II. Out of the AEG I tumors, 26 were classified as AdGEJ. Regardless of the classification system, more proximally located tumors showed less aggressive behavior with lower rates of lymph node metastases, lymphatic, venous and perineural invasion, better histological differentiation (p < 0.05 each) and were more frequently associated with pre-neoplastic Barrett's mucosa (p < 0.001). Histologically, the tumors displayed intestinal morphology in the majority of cases. IHC showed non-conclusive patterns with a frequent CK7+/CK20+ immunophenotype in all tumors, but also a gastric MUC5AC+ and MUC6+ phenotype in some proximal tumors. In conclusion, histology of the tumors and IHC failed to distinguish reliably between more proximal and more distal tumors. The presence of Barrett's mucosa rather than location alone, however, may help to further differentiating adenocarcinomas arising in this region and may be indicative for a particular biologic type.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Neoplasias Esofágicas , Patologia Cirúrgica , Neoplasias Gástricas , Humanos , Esôfago de Barrett/cirurgia , Esôfago de Barrett/complicações , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Adenocarcinoma/patologia
14.
Cancers (Basel) ; 14(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36551654

RESUMO

Background: The applicability of UICC TNM staging for gastric cancer (GC) patients treated with neoadjuvant chemotherapy (nCTX) and surgery was not yet analyzed in comparison to patients undergoing primary surgery (PS). The purpose of this analysis was to analyze if the prognostic impact of TNM staging after nCTx is comparable with PS. Methods: Data for patients having been treated for GC with or without nCTx between 1990 and 2016 were analyzed. Uni-(URA) and multivariable regression analyses (MRA) were performed to identify predictors. Survival according to the UICC 8th edition stages was analyzed by the Kaplan−Meier method and cox regression analysis. Propensity score matching (PSM) was performed to balance for confounders. Results: 1149 patients with GC were eligible for primary analysis. URA demonstrated age (p < 0.0001), tumor localization (p < 0.0001), clinical UICC-stage, complications, UICC stage 0, IIB-IIIC, Lauren subtype, grading, and R-stage to be significantly associated with OS. MRA revealed that age, distal tumor localization, more than 25 dissected lymph nodes, UICC stage 0, IIB-IIIC, and Lauren subtype were significantly and independently related to OS. After PSM, survival analyses revealed only a significant difference for pN2/ypN2 (p = 0.03), while all other T and N stages were comparable. Conclusion: UICC dependent survival stages do not change significantly after nCTx treatment for GC. Therefore, UICC staging in its present version is applicable to patients undergoing nCTx.

15.
J Clin Med ; 11(23)2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36498752

RESUMO

(1) Background: Minimally invasive oesophagectomy (MIE) with intrathoracic anastomosis is increasingly used in treating patients with oesophageal cancer. Anastomotic leakage (AL) remains a critical perioperative complication, despite recent advances in surgical techniques. It remains unclear to what extent the size of the circular stapler (CS), a 25 mm CS or a bigger CS, may affect the incidence of AL. This study aimed to evaluate whether the CS size in oesophagogastrostomy affects the postoperative AL rates and related morbidity in MIE. (2) Methods: We conducted a retrospective review of consecutive patients who had undergone thoracic MIE between August 2014 and July 2019 using a CS oesophagogastric anastomosis at the level of the Vena azygos. The patients were grouped according to CS size (mm): small-sized (SS25) and large-sized (LS29). The patient demographics, data regarding morbidity, and clinical outcomes were compared. The primary outcome measure was the AL rate related to the stapler size. (3) Results: A total of 119 patients were included (SS25: n = 65; LS29: n = 54). Except for the distribution of squamous cell carcinoma, the demographics were similar in each group. The AL rate was 3.7% in the LS29 group and 18.5% in the SS25 group (p = 0.01). The major morbidity (CD ≥ 3a) was significantly more frequent in the SS25 group compared with the LS29 group (p = 0.02). CS size, pulmonary complications, and cardiovascular disease were independent risk factors for AL in the multivariate analysis. (4) Conclusions: A 29 mm CS is associated with significantly improved surgical outcomes following standard MIE at the level of the azygos vein and should be conducted whenever technically feasible.

16.
Sci Rep ; 12(1): 19279, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369521

RESUMO

Autonomic and vascular failures are common phenotypes of sepsis, typically characterized by tachycardia despite corrected hypotension/hypovolemia, vasopressor resistance, increased arterial stiffness and decreased peripheral vascular resistance. In a 5-day swine experiment of polymicrobial sepsis we aimed at characterizing arterial properties and autonomic mechanisms responsible for cardiovascular homeostasis regulation, with the final goal to verify whether the resuscitation therapy in agreement with standard guidelines was successful in restoring a physiological condition of hemodynamic profile, cardiovascular interactions and autonomic control. Twenty pigs were randomized to polymicrobial sepsis and protocol-based resuscitation or to prolonged mechanical ventilation and sedation without sepsis. The animals were studied at baseline, after sepsis development, and every 24 h during the 3-days resuscitation period. Beat-to-beat carotid blood pressure (BP), carotid blood flow, and central venous pressure were continuously recorded. The two-element Windkessel model was adopted to study carotid arterial compliance, systemic vascular resistance and characteristic time constant τ. Effective arterial elastance was calculated as a simple estimate of total arterial load. Cardiac baroreflex sensitivity (BRS) and low frequency (LF) spectral power of diastolic BP were computed to assess autonomic activity. Sepsis induced significant vascular and autonomic alterations, manifested as increased arterial stiffness, decreased vascular resistance and τ constant, reduced BRS and LF power, higher arterial afterload and elevated heart rate in septic pigs compared to sham animals. This compromised condition was persistent until the end of the experiment, despite achievement of recommended resuscitation goals by administered vasopressors and fluids. Vascular and autonomic alterations persist 3 days after goal-directed resuscitation in a clinically relevant sepsis model. We hypothesize that the addition of these variables to standard clinical markers may better profile patients' response to treatment and this could drive a more tailored therapy which could have a potential impact on long-term outcomes.


Assuntos
Sistema Nervoso Autônomo , Sepse , Animais , Sistema Nervoso Autônomo/fisiologia , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Artérias Carótidas , Frequência Cardíaca/fisiologia , Ressuscitação , Sepse/terapia , Suínos , Vasoconstritores
17.
Nat Commun ; 13(1): 5711, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175413

RESUMO

Artificial Intelligence (AI) can support diagnostic workflows in oncology by aiding diagnosis and providing biomarkers directly from routine pathology slides. However, AI applications are vulnerable to adversarial attacks. Hence, it is essential to quantify and mitigate this risk before widespread clinical use. Here, we show that convolutional neural networks (CNNs) are highly susceptible to white- and black-box adversarial attacks in clinically relevant weakly-supervised classification tasks. Adversarially robust training and dual batch normalization (DBN) are possible mitigation strategies but require precise knowledge of the type of attack used in the inference. We demonstrate that vision transformers (ViTs) perform equally well compared to CNNs at baseline, but are orders of magnitude more robust to white- and black-box attacks. At a mechanistic level, we show that this is associated with a more robust latent representation of clinically relevant categories in ViTs compared to CNNs. Our results are in line with previous theoretical studies and provide empirical evidence that ViTs are robust learners in computational pathology. This implies that large-scale rollout of AI models in computational pathology should rely on ViTs rather than CNN-based classifiers to provide inherent protection against perturbation of the input data, especially adversarial attacks.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Fontes de Energia Elétrica , Conhecimento , Fluxo de Trabalho
20.
Am J Physiol Gastrointest Liver Physiol ; 323(4): G348-G361, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36044679

RESUMO

Impaired oxygen utilization has been proposed to play a significant role in sepsis-induced liver dysfunction, but its magnitude and temporal course during prolonged resuscitation is controversial. The aim of this study is to evaluate the capability of the liver to increase oxygen extraction in sepsis during repeated acute portal vein blood flow reduction. Twenty anesthetized and mechanically ventilated pigs with hepatic hemodynamic monitoring were randomized to fecal peritonitis or controls (n = 10, each). After 8-h untreated sepsis, the animals were resuscitated for three days. The ability to increase hepatic O2 extraction was evaluated by repeated, acute decreases in hepatic oxygen delivery (Do2) via reduction of portal flow. Blood samples for liver function and liver biopsies were obtained repeatedly. Although liver function tests, ATP content, and Do2 remained unaltered, there were signs of liver injury in blood samples and overt liver cell necrosis in biopsies. With acute portal vein occlusion, hepatic Do2 decreased more in septic animals compared with controls [max. decrease: 1.66 ± 0.68 mL/min/kg in sepsis vs. 1.19 ± 0.42 mL/min/kg in controls; portal venous flow (Qpv) reduction-sepsis interaction: P = 0.028]. Hepatic arterial buffer response (HABR) was impaired but recovered after 3-day resuscitation, whereas hepatic oxygen extraction increased similarly during the procedures in both groups (max. increase: 0.27 ± 0.13 in sepsis vs. 0.18 ± 0.09 in controls; all P > 0.05). Our data indicate maintained capacity of the liver to acutely increase O2 extraction, whereas blood flow regulation is transiently impaired with the potential to contribute to liver injury in sepsis.NEW & NOTEWORTHY The capacity to acutely increase hepatic O2 extraction with portal flow reduction is maintained in sepsis with accompanying liver injury, but hepatic blood flow regulation is impaired.


Assuntos
Hemodinâmica , Sepse , Trifosfato de Adenosina , Animais , Artéria Hepática , Circulação Hepática/fisiologia , Oxigênio , Suínos
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