Real-time lipid patterns to classify viable and necrotic liver tumors.

Real-time tissue classifiers based on molecular patterns are emerging tools for fast tumor diagnosis. Here, we used rapid evaporative ionization mass spectrometry (REIMS) and multivariate statistical analysis (principal component analysis-linear discriminant analysis) to classify tissues with subsequent comparison to gold standard histopathology. We explored whether REIMS lipid patterns can identify human liver tumors and improve the rapid characterization of their underlying metabolic features. REIMS-based classification of liver parenchyma (LP), hepatocellular carcinoma (HCC), and metastatic adenocarcinoma (MAC) reached an accuracy of 98.3%. Lipid patterns of LP were more similar to those of HCC than to those of MAC and allowed clear distinction between primary and metastatic liver tumors. HCC lipid patterns were more heterogeneous than those of MAC, which is consistent with the variation seen in the histopathological phenotype. A common ceramide pattern discriminated necrotic from viable tumor in MAC with 92.9% accuracy and in other human tumors. Targeted analysis of ceramide and related sphingolipid mass features in necrotic tissues may provide a new classification of tumor cell death based on metabolic shifts. Real-time lipid patterns may have a role in future clinical decision-making in cancer precision medicine.

Columellar Reconstruction After Nasal Continuous Positive Airway Pressure Associated Necrosis.

Though a life-saving modality in neonatal intensive care units, nasal continuous positive airway pressure (nCPAP) carries a small risk of irreversible ischemia and necrosis of the columella due to the configuration of the pressure delivery system. Iatrogenic injuries to the columella after nCPAP use result in a spectrum of disfigurement and functional airway obstruction. The authors performed a retrospective review of patients evaluated for nCPAP-related columellar deformities by the Division of Plastic and Reconstructive Surgery at the authors' institution over a 10-year period to assess reconstructive outcomes. Of 7 patients evaluated, 3 underwent reconstruction using a combination of cartilaginous framework reshaping and local tissue flaps. After a mean follow-up period of 78 months, patients had satisfactory aesthetic and functional results. Based on the authors' observations, columellar necrosis secondary to nCPAP can be divided into 3 categories: Type A demonstrates mild notching of the columella; Type B has an absent columella without notable nasal tip depression; Type C has an absent columella with nasal tip depression, with or without external nasal valve obstruction. Reconstructive needs should be individually tailored based on the degree of nasal tip depression, cartilaginous support, and soft tissue availability.

Necrotizing soft tissue infections in the intensive care unit.

Necrotizing soft tissue infection is a severe illness that is associated with significant morbidity and mortality. It is often caused by a wide spectrum of pathogens and is most frequently polymicrobial. Care for patients with necrotizing soft tissue infection requires a team approach with expertise from critical care, surgery, reconstructive surgery, and rehabilitation specialists. The early diagnosis of necrotizing soft tissue infection is challenging, but the keys to successful management of patients with necrotizing soft tissue infection are early recognition and complete surgical debridement. Early initiation of appropriate broad-spectrum antibiotic therapy must take into consideration the potential pathogens. Critical care management components such as the initial fluid resuscitation, end-organ support, pain management, nutrition support, and wound care are all important aspects of the care of patients with necrotizing soft tissue infection. Soft tissue reconstruction should take into account both functional and cosmetic outcome.

Acute lead arsenate poisoning in beef cattle in Uruguay.

We describe and illustrate lesions in an outbreak of lead arsenate poisoning in beef cattle that ingested pesticide residues stored in an abandoned building of a former orange orchard. Of 70 exposed cattle, 14 had diarrhea, paresis, ataxia, recumbency, and/or seizures. Ten of the affected animals died after a clinical course of 12-18 h. Pathologic findings in 3 steers included extensive necrohemorrhagic, ulcerative rumenitis, omasitis, and abomasitis; lymphocytolysis in lymphoid organs; and nephrosis. Hepatic arsenic and lead levels in cases 1-3 were 20, 24, and 31 ppm, and 8.3, 25, and 9.4 ppm, respectively. Lesions in the forestomachs and lymphoid tissues have been rarely reported in cases of lead arsenate poisoning. In southern South America, these lesions are indistinguishable from those produced by Baccharis coridifolia, a toxic plant that contains macrocyclic trichothecenes, thus these conditions should be considered in the differential diagnosis of necrotizing lesions in alimentary and lymphoid organs.

Targeting of regulated necrosis in kidney disease.

The term acute tubular necrosis was thought to represent a misnomer derived from morphological studies of human necropsies and necrosis was thought to represent an unregulated passive form of cell death which was not amenable to therapeutic manipulation. Recent advances have improved our understanding of cell death in acute kidney injury. First, apoptosis results in cell loss, but does not trigger an inflammatory response. However, clumsy attempts at interfering with apoptosis (e.g. certain caspase inhibitors) may trigger necrosis and, thus, inflammation-mediated kidney injury. Second, and most revolutionary, the concept of regulated necrosis emerged. Several modalities of regulated necrosis were described, such as necroptosis, ferroptosis, pyroptosis and mitochondria permeability transition regulated necrosis. Similar to apoptosis, regulated necrosis is modulated by specific molecules that behave as therapeutic targets. Contrary to apoptosis, regulated necrosis may be extremely pro-inflammatory and, importantly for kidney transplantation, immunogenic. Furthermore, regulated necrosis may trigger synchronized necrosis, in which all cells within a given tubule die in a synchronized manner. We now review the different modalities of regulated necrosis, the evidence for a role in diverse forms of kidney injury and the new opportunities for therapeutic intervention.

A novel bowel necrosis classification system and examination of patient outcomes in incarcerated groin hernia patients.

The objective of this study was to determine a classification system for BN in incarcerated groin hernia patients and to explore the possible relationship between BN staging and patient outcomes. Incarcerated groin hernia patients treated with emergency bowel resection from January 2008 to December 2013 were screened for inclusion in a prospective study. A novel three-stage classification system was proposed for BN (BN stages I-III) and correlations between adverse events (AEs) and mortality with BN stage were determined. A total of 108 patients were included, with 71, 26, and 11 patients in BN stages I, II, and III, respectively. AEs, which included wound and intra-abdominal infections and other systemic complications, increased with higher BN stage (all P < 0.05). Mortality increased with BN stage, with 2.8%, 7.7%, and 27.3% at BN stages I, II, and III, respectively (P < 0.05). The proposed BN staging system can objectively reflect the degree of bowel damage and its corresponding adverse outcomes.

Classification of myonecrosis induced by snake venoms: venoms from the prairie rattlesnake (Crotalus viridis viridis), western diamondback rattlesnake (Crotalus atrox) and the Indian cobra (Naja naja naja).

The pathogenesis of myonecrosis induced by three different snake venoms was studied by light microscopic examination of skeletal muscle tissue taken at time periods ranging from 0.25 hr to 4 weeks after an intramuscular injection of the venom into mice. It was possible to identify different types of myonecrosis based on the abnormal morphologic states of the damaged cells. The types of myonecrosis observed correlated with the types of components present in the venom injected. Venoms containing direct acting toxins such as myotoxin a or phospholipase A2 induced specific types of myonecrosis. Also, venoms containing hemorrhagic toxins produced a type of myonecrosis similar to that induced by pure hemorrhagic toxins. The pathogenesis of each type of myonecrosis could be divided into the same four phases based on the pathologic states of the affected cells and the time after injection. During the 'early phase' (0.25-3 hr) affected muscle cells were in several different pathologic states reflecting the types of components present in the venom injected. During the 'intermediate phase' (6-24 hr) the pathologic state of the damaged cells had changed and depending on the venom new states might be present. By the 'late phase' (48-96 hr) all damaged cells have reached a common pathologic state of necrosis. The 'final phase' (1-4 weeks) is characterized by regeneration (partial or complete) of muscle cells. Although the number of different types of myonecrosis depended on the type of venom injected, i.e. Naja naja naja venom produced only two different types whereas Crotalus atrox venom produced at least four different types, cells of each tpe of myonecrosis progressed through the same four phases. In studies of the myotoxicity of snake venoms it is important to examine tissues taken during the early and intermediate phases to obtain accurate and useful information on the types of myonecrosis caused by the venom.

Necroptosis: an emerging form of programmed cell death.

Necrosis plays an important role in multiple physiological and pathological processes. Recently, a relatively new form of necrosis has been characterized as "necroptosis". Morphologically, necroptosis exhibits the features of necrosis; however, necroptosis exhibits a unique signaling pathway that requires the involvement of receptor interaction protein kinase 1 and 3 (RIP1 and RIP3) and can be specifically inhibited by necrostatins. Necroptosis has been found to contribute to the regulation of immune system, cancer development as well as cellular responses to multiple stresses. In this review, we will summarize the signaling pathway, biological effects and pathological significance of this specific form of programmed cell death.

Terapia fotodinâmica em células de tumores pancreáticos humanos: eficiência e análise das vias mediadoras de citotoxicidade / Photodynamic therapy in human pancreatic tumors: efficiency and analysis of cytotoxicity mediator pathways

O adenocarcinoma de ducto pancreático (PDAC) é a quarta causa de morte em decorrência de neoplasias nos países ocidentais. Atualmente, a cirurgia ressectiva é a única possibilidade de cura para a doença, porém, a recidiva tumoral acontece em menos de um ano após a intervenção cirúrgica, mesmo com a quimioterapia adjuvante. A terapia fotodinâmica (PDT) é uma alternativa promissora no tratamento do câncer. No entanto, pouco se sabe sobre o uso da PDT em tumores pancreáticos. Portanto, o objetivo deste trabalho foi avaliar a eficiência da PDT com o azul de metileno (MB) como fotossensibilizador (MB-PDT) em induzir a morte de linhagens de PDAC humanas (AsPC-1, Panc-1, MIAPaCa-2 e BxPC-3) e estudar a contribuição de vias de necrose regulada nos efeitos citotóxicos da terapia sobre estes modelos. Os resultados obtidos mostraram que a MB-PDT foi capaz de induzir a morte massiva das células de PDAC. Além disso, eles indicaram que há dois perfis de susceptibilidade entre as quatro linhagens estudadas quando submetidas a MBPDT com 4,5 J/cm2 de energia e 6min de irradiação. De acordo com os dados apresentados, a diferença nas sensibilidades das linhagens à terapia não está associada à diferenças na capacidade de incorporação do MB ou na localização sub-celular do fotossensibilizador nas diferentes células, uma vez que a localização é, predominantemente, lisossomal em todas elas. Adicionalmente, mostrou-se que as linhagens menos susceptíveis ao tratamento, MIAPaCa-2 e Panc-1, apresentam níveis significativamente menores de RIPK3 e MLKL, dois dos componentes do necrossomo, essenciais para a execução da necroptose. Além disso, foi visto que a MB-PDT induz um aumento de fosforilação de MLKL em AsPC-1, demonstrando a ativação da necroptose após a terapia nestas células, mas não em MIAPaCa-2 (menos responsiva à terapia com 4,5 J/cm2 deenergia e 6min de tempo de irradiação). Ainda, a inibição da via de sinalização necroptótica diminuiu significativamente as porcentagens de morte das células mais susceptíveis (BxPC-3 e AsPC-1), não alterando a resposta de Panc-1 e MIAPaCa-2, corroborando a ativação e importância da necroptose para a citotoxicidade da MB-PDT. Finalmente, neste trabalho foi mostrado que o aumento do tempo de irradiação, mantendo-se a quantidade total de energia aplicada no tratamento, melhora a eficiência da MB-PDT em induzir a morte das células que apresentam limitações para executar a necroptose, sugerindo que mais de uma via de morte esteja sendo ativada após a terapia e que o tempo de irradiação atuaria modulando esta ativação. Complementarmente, foi mostrado que os tempos maiores de irradiação aumentam o estresse oxidativo intracelular que é acompanhado por uma diminuição significativa do conteúdo intracelular de glutationa reduzida (GSH), indicando, preliminarmente, que a ferroptose pode estar sendo acionada após os protocolos mais longos de irradiação. Coletivamente, os resultados apresentados neste trabalho confirmam a eficiência da MB-PDT no tratamento de diferentes linhagens de PDAC, indicando que a necroptose está sendo ativada e contribuindo para a citotoxicidade da terapia sobre as células que não apresentam resistência à esta via de morte. Ainda, eles demonstram que o aumento do tempo de irradiação pode transpor a barreira de resistência de algumas linhagens à terapia, provavelmente por induzir a ativação de outras vias de necrose regulada, mostrando a importância da otimização do protocolo de tratamento no aumento da eficiência da MB-PDT sobre os tumores de pâncreas. Finalmente, os resultados confirmam a MB-PDT como alternativa eficaz no tratamento do PDAC, apresentando um amplo espectro de atuação sobre subtipos tumorais resistentes à vias clássicas de morte celular, uma característica importante no contexto de uma terapia anti-cancer

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of death due to neoplasms in western countries. Currently, resective surgery is the only therapetical approach to cure this disease, but tumor´s recurrence occurs less than one year after the surgery, even with adjuvant chemotherapy. Photodynamic therapy (PDT) is a promising alternative for the cancer treatment. However, the efficacy of PDT to treat pancreatic tumors as well as the mechanisms involved in the induction of tumorigenic cell death remain unclear. For this purpose, in this study, we set out to evaluate the efficacy of PDT using methylene blue (MB) as a photosensitizer (MB-PDT), in inducing death of human PDAC derived cell lines (AsPC-1, Panc-1, MIAPaCa-2 and BxPC-3) and to deeper investigate the contribution of necroptosis to the cytotoxic effects of the therapy. We observed that MB-PDT was able to induce massive death of PDAC cells. Moreover, our results indicated that upon MB-PDT (4.5 J/cm2 energy and 6min of irradiation time), there were two susceptibility profiles among the four cell lines studied. Data also showed that this differential profile of cell response was neither associated with the differences in the MB incorporation capacity nor with the subcellular location of the photosensitizer, since the localization was predominantly lysosomal in all of tested cell lines. In addition, less susceptible cells, MIAPaCa-2 and Panc-1, showed significantly lower levels of RIPK3 and MLKL, two of the necrosome components, essential for triggering necroptosis. Furthermore, while MB-PDT (4.5 J/cm2 and 6min of irradiation) has been able to increase MLKL´s phosphorylation levels, an essential step in necroptosis induction, in AsPC-1cells, less responsive MIAPaCa-2 cells presented no variations on the phosphorylation state of this pseudokinase. Moreover, pharmacological inhibition of the necroptotic signaling pathway significantly decreased cell death percentages of the most susceptible cells (BxPC-3 andAsPC-1), without altering the response of Panc-1 and MIAPaCa-2, corroborating that activation of necroptosis was strongly involved in the cytotoxicity of MB-PDT. Finally, this work showed that increasing the irradiation time improved the efficacy of MB-PDT in killing cells which display limitations to perform necroptosis, suggesting that the irradiation time would be modulating the degree of oxidative stress generated and this stimuli would in turn, be responsible for triggering other regulated cell death pathways in a RIKP3 and MLKL independent way. Indeed, this increase in oxidative stress was accompanied by a significant decrease in GSH, a global indicatior of less antioxidant cell capacity, preliminarily pointing at the induction of ferroptosis by longer irradiation protocols. In summary, we demonstrated that MB-PDT is able to induce cell death in different PDAC cell lines and that different regulated cell death mechanisms are being activated upon MB-PDT induction. Furthermore, it was demonstrated that increased irradiation time may overcome the resistance barrier of some cell lines, probably inducing the activation of other regulated cell death pathways, showing the importance of optimizing the irradiation protocol in order to maximize the efficacy of the therapy. Finally, our observations point MB-PDT as an alternative and effective therapy for pancreatic cancer treatment, displaying a broad-spectrum action on tumors displaying different resistance mechanisms to classic cell death pathways, a desired property for improving an anticancer therapy

AIF-mediated programmed necrosis: a highly regulated way to die.

Historically, two main forms of cell death have been distinguished: apoptosis and necrosis. Apoptosis was initially considered as the only physiological and programmed form of cell death. This type of death is recurrently associated with caspases, a family of cysteine proteases activated in apoptotic conditions. However, it is now widely recognized that programmed cell death (PCD) can also occur in the complete absence of caspase activation. The existence of non-caspase PCD pathways was corroborated by the discovery of caspase-independent executioners, such as the mitochondrial protein Apoptosis-Inducing Factor (AIF). Necrosis has often been viewed as an accidental and uncontrolled cell death process. Nevertheless, increasing evidence shows that, like apoptosis, necrosis could be a highly orchestrated type of PCD. Indeed, apoptosis and necrosis present more similarities than it has been originally thought. Here, we summarize the different classifications of PCD and the current knowledge of a necrotic PCD pathway mediated by AIF: alkylating DNA-damage mediated death. We also outline the molecular mechanisms controlling this form of PCD and discuss their potential relevance in physiological and pathological settings. These emerging data on the molecular mechanisms regulating programmed necrosis may certainly have potent therapeutic consequences in treating both apoptotic-resistant tumors and degenerating adult neurons.

Patterns of cell death.

Cell death takes two distinct forms, necrosis and apoptosis. Necrosis is a degenerative phenomenon that follows irreversible injury. Apoptosis, in contrast, appears to be an active process requiring protein synthesis for its execution; it is implicated in physiological regulation of tissue size, and, where it occurs pathologically, a homeostatic role for the death is often evident. Morphologically, apoptosis involves condensation of the nuclear chromatin and cytoplasm, fragmentation of the nucleus, and budding of the whole cell to produce membrane-bounded bodies in which organelles are initially intact. These bodies are disposed of by adjacent cells without inflammation. Biochemically, there is distinctive internucleosome cleavage of DNA in apoptosis, which is quite different from the random DNA degradation observed in necrosis.

Anatomy and quantification of myocardial cell death.

Irreversible damage of the myocardial cells may show different morphologic aspects in relation to the type of dysfunction of their contraction-relaxation cycle. Attenuation of the muscle fibers with elongation of the sarcomeres and nuclei are the earliest modifications (systolic paradoxical bulging and stretching by the intraventricular pressure) when the myocells stop their function in irreversible relaxation. This 'atonic' death is pathognomonic of myocardial infarction (infarct or coagulation necrosis) and the lesion evolves with typical structural changes. An opposite and entirely different morphologic pattern is seen in the 'tetanic' death in which the myocardial cells arrest in irreversible contraction (coagulative myocytolysis or contraction band necrosis). Segmental (paradiscal bands) or pancellular hypercontraction with extreme shortening of the sarcomeres and subsequent myofibrillar rhexis alternated with irregular cross band formations (holocytic bands) are characteristic of this necrosis seen in numerous human and experimental conditions and specific of catecholamine toxicity. The third type of damage is observed in low output syndromes in which increasing edematous vacuolization and disappearance of the myofibrils (colliquative myocytolysis) are the main structural alterations. They are suggestive of progressive functional reduction leading to dilatative insufficiency ('failing' death). These clear-cut morphofunctional patterns indicate distinctive biochemical impairments and pathogenesis. In particular their frequent presence in and possible association with the different aspects of the ischemic heart disease presuppose other non-ischemic mechanisms responsible for complications and death in this modern epidemic.

Proposed classification and pathologic mechanisms of purpura fulminans and skin necrosis.

The syndromes of purpuric lesions associated with a thrombotic mechanism are very rare in the general population. Dermal vascular thrombosis, however, can be devastating and associated with significant morbidity and mortality. These syndromes share common features in their clinical course, pathogenesis, and histology. Although these syndromes can be initiated by either the hemostatic or inflammatory pathways, both pathways center around perturbations of the endothelial cell, which promote thrombosis. If animal models or better testing can be developed, enhanced appreciation of mechanisms underlying purpura fulminans may be deduced. Characterization of the pathophysiology may then allow directed treatment modalities that could limit the course of these syndromes and reduce morbidity and mortality.

Necrotizing fasciitis: a classification of necrotizing soft tissue infections.

Necrotizing fasciitis is a rare, often fatal soft tissue infection. It still remains a confusing entity because of the nomenclature and multiple subtypes described in the past. An interesting case study of a patient with necrotizing fasciitis secondary to nonclostridial gas gangrene is presented. A comprehensive review of necrotizing fasciitis, its disease process and treatment modalities will be discussed.

[Necrotizing vasculitis with predominant kidney involvement]. / Vasculitis necrotizante con predominio de afección renal.

We report five patients with necrotizing vasculitis with predominant renal involvement; the diagnostic and therapeutics was effected completely at regional hospital. We detach: a) the clinical presentation's forms with rapidly progressive renal failure with microscopic hematuria and minimal proteinuria; b) the biopsy of kidney with necrotizing vasculitis or necrotizing glomerulonephritis (microscopic polyarteritis). We review the necrotizing vasculitis with predominant renal involvement in its pathogenic, clinical and histological aspects, and we insist that the diagnostic and early treatment are fundamental for prognostic's improvement of these patients. We conclude that this diagnostic and treatment can be made in regional hospitals with sensible physicians by the theme.

Oxigenoterapia hiperbárica para infecciones necrotizantes de partes blandas / Hyperbaric oxygenotherapy for necrotizing infections of soft parts

Introducción: La Oxigenoterapia Hiperbárica (OHB) se ha convertido en el tratamiento de elección de numerosas patologías. Sin embargo, su rol en el tratamiento de las Infecciones Necrotizantes de partes blandas (INPB) es aún controvertido.Objetivo: Evaluar el beneficio de la Oxigenoterapia Hiperbárica (OHB) en el tratamiento de las Infecciones Necrotizantes de partes blandas (INPB).Método: Retrospectivo, revisión de historias clínicas y seguimiento de los casos. Durante el período de Enero 1996 a Diciembre2002, una población de 42 pacientes con INPB, se categorizó las lesiones de acuerdo a profundidad según la clasificación de Ámsterdam y se los dividió en 2 grupos: el grupo I (n = 18) que completó el protocolo de 10 sesione de OHB de 60 minutos cada una a 2.5 atmósferas absolutas (ATA), iniciando el 1º día del postoperatorio y el grupo II (n = 24) que no lo completó. En todos los casos se realizó desbridamiento quirúrgico precoz y antibioticoterapia.Resultado: En el grupo I hubo 12 (66.6%) recuperaciones completas, 5 (27.7%) secuelas leves y 1 (5.7%) grave, en el grupo II hubo 5 (20.8%) recuperaciones completas, 8 (33.4%) secuelas leves y 5 (20.8%) graves. La flora patógena fue en el 85.7% de los casos polimicrobiana. La mortalidad global fue del 25%, todos del grupo II.Conclusión: Se observó una relación inversamente proporcional entre el número de sesiones de OHB y la morbimortalidad. La OHB fue beneficiosa en esta serie como tratamiento complementario a la cirugía y los antibióticos.

Análisis comparativo de la cirugía de la necrosis pancreática en las dos últimas décadas / Comparative study of surgery in pancreatic necrosis in the last 2 decades

Con la finalidad de examinar nuestros resultados en el tratamiento quirúrgico de la necrosis pancreática se analizan retrospectivamente 31 pacientes a los que se les practicó necrosectomía en un lapso de 20 años (1971-1990). En la serie predominó el sexo masculino (22 enfermos). Se detallan las características clínicas que, junto a las pruebas de laboratorio y diagnóstico por imágenes, permitieron sospechar la necrosis con infección y decidir la oportunidad quirúrgica. La mortalidad global postoperatoria fue de 11 pacientes (35,48 por ciento). En la primera década sobre 12 operados observamos una letalidad de 8 casos (66,66 por ciento), mientras que en el segundo decenio ésta se redujo a 3 observaciones (15,78 por ciento). La completa exéresis de los tejidos desvitalizados y el aporte de una correcta reanimación pre y postoperatoria en unidades de cuidado intensivo, sumados a una nutrición parenteral o enteral que permitió evitar una realimentación oral temprana, a un mejor manejo infectológico y a la incorporación de nuevos procedimientos de diagnóstico por imágenes constituyeron la base para mejorar los resultados en los últimos 19 casos de nuestra casuística

Loxosceles y loxoscelismo en Piura / Loxosceles and loxoscelism in Piura

Los autores presentan dos casos con loxocelismo cutaneo y mordedura de araña del género Loxoceles sp. en la casa de uno de los pacientes. Estos son uno de los primeros caos de loxocelismo y Loxoceles en Piura