Participation of autophagy in acute lung injury induced by seawater.

Seawater drowning can lead to acute lung injury (ALI). However, the molecular and cellular mechanisms underlying this phenomenon remain elusive. The overall aim of this study is to clarify the role of autophagy in seawater-induced ALI, by which we can further understand the molecular mechanism and develop new methods for prevention and treatment of seawater-induced ALI. In this study, electron microscopy, western blot analysis, and RT-PCR were used to detect autophagy in lung tissues. Moreover, arterial blood gas analysis, lung weight coefficient, TNF-α, IL-8 in bronchoalveolar fluid (BALF), histopathology were used to detect the lung injury of seawater exposure. An inhibitor of autophagy (3-Methyladenine, 3-MA) was injected intraperitoneally before seawater exposure to further explore the role of autophagy in ALI. Electron microscopy revealed increasing autophagosomes in alveolar epithelial cell in seawater group compared with the control. The transcription and expression levels (mRNA and protein levels) of the LC3 II significantly increased in lung tissue of seawater group compared with those in control group. Furthermore, the alterations of autophage were basically consistent with the changes in arterial blood gas, lung weight coefficient, TNF-α, IL-8 in BALF and morphologic findings. In addition, inhibition of autophagy by 3-MA partly ameliorated seawater-induced ALI, as indicated by reduced lung weight coefficient and TNF-α in BALF, as well as increased PaO2. In conclusion, seawater aspiration triggered autophagy, and autophagy may be a scathing factor responsible for ALI induced by seawater.

Drowning.

Approximately 500,000 deaths due to drowning are reported annually, 30,000 of which are reported in Europe. Because of the relatively low incidence of drowning victims at emergency departments, most emergency physicians do not routinely handle drowning victims. Although confusion regarding the classification and pathophysiology of drowning could be reduced by following the Utstein style consensus, the application of therapeutic modalities and, most important, the estimation of probable prognostic outcomes remain difficult for emergency physicians. This article presents an overview of the classification, pathophysiology, emergency-department treatment and prognostic outcomes of drowning accidents.

Muertes por sumersión. Revisión y actualización de un tema clásico de la medicina forense / Deaths by drowning. A classic topic in forensic medicine revisited

La recuperación de un cadáver del agua plantea siempre múltiples y variadas cuestiones a las que no es posible encontrar respuesta adecuada en algunas ocasiones; y ello a pesar de la riqueza de signos que suelen ofrecer los cuadros de asfixia por sumersión. En el presente trabajo se realiza una revisión crítica y actualización de las muertes por sumersión a la vista de los recientes conocimientos sobre las alteraciones fisiopatológicas inducidas por estos cuadros, poniendo especial interés en los casos de cuerpos recuperados del agua con “pulmones secos”. Los hallazgos necrópsicos son objeto de revisión, así como los estudios histopatológicos e histoenzimáticos. Se realiza, asimismo, una amplia revisión de los exámenes complementarios de tipo biológico y tanatoquímico, incidiendo de manera particular sobre el estudio de los componentes químicos (estroncio) y sobre el papel diagnóstico que puede representar el estudio de las diatomeas, con sus posibles causas de error. También se analizan las aportaciones diagnósticas que pueden realizar, en determinados casos, el estudio de los protozoos ciliados, las algas verdes o el análisis bacteriológico de la sangre. Otros marcadores son objeto de consideración, y de manera particular, el estudio del surfactante pulmonar que está abriendo nuevas vías de diagnóstico en los cuadros de sumersión. Se formulan, finalmente, algunas consideraciones en torno a los diferentes procedimientos propuestos para el establecimiento de la data de la muerte

The recovery of a corpse from the water raises always multiple and varied questions, to which it is not possible to find an adequate answer in some occasions, in spite of the richness of signs that use to offer the cases of asphyxia by drowning. In this paper, a critical review and update of deaths by drowning is presented, taking into account the recent knowledge on the physiopathological alterations induced by these pictures, with special interest to the cases of bodies recovered of the water with "dry lungs ". The postmortem findings are reviewed, as well as the histopathological and histoenzymatic studies. A wide review of the ancillary examinations from biology to tanatochemistry is also performed, stressing particularly the study of the chemical components (Strontium) and the diagnostic role that can represent the study of diatoms, with their possible causes of error. The diagnostic contributions that can made, in certain cases, the study of the ciliated protozoa, the green algae or the bacteriological analysis of blood are also analyzed. Other markers are object of consideration, specifically the study of the pulmonary surfactant that is opening new diagnostic ways in drowning cases. Finally, some considerations concerning the different procedures proposed for the establishment of the time of death are formulated

Pleural effusion in bodies recovered from water.

Both in saltwater and freshwater drowning cases, a common autopsy sign is pleural effusion. However, the factors that determine the amount of pleural effusion have not been well established. An attempt was therefore made to correlate the amount of pleural fluid in bodies recovered from water with several parameters registered on the judicial files as well as autopsy findings from the years 1994-1998. The number of cases with pleural fluid increase was found to be very high in saltwater drowning (P<0.001). But, when the freshwater and saltwater drowning cases with pleural fluid increase were compared according to pleural fluid amount, no significant difference was detected (521+/-340 and 768+/-536 ml, respectively). Although there was a positive correlation between the decomposition degree and the fluid in the pleural cavity, a relative decrease was detected in the amount of effusion contrary to the expectations in cases of extreme decomposition. Pleural fluid amount provides significant data about the type of water and the cause of death in early postmortem interval. And there is a link between the time spent in water and the amount of pleural effusion. With the advance of the postmortem interval, decomposition level and the duration of immersion should be taken into account in differential diagnosis.

Hypoxic encephalopathy after near-drowning studied by quantitative 1H-magnetic resonance spectroscopy.

Early prediction of outcome after global hypoxia of the brain requires accurate determination of the nature and extent of neurological injury and is cardinal for patient management. Cerebral metabolites of gray and white matter were determined sequentially after near-drowning using quantitative 1H nuclear magnetic resonance spectroscopy (MRS) in 16 children. Significant metabolite abnormalities were demonstrated in all patients compared with their age-matched normal controls. Severity of brain damage was quantified from metabolite concentrations and ratios. Loss of N-acetylaspartate, a putative neuronal marker, from gray matter preceded that observed in white matter and was more severe. Total creatine decreased, while lactate and glutamine/glutamate concentrations increased. Changes progressed with time after injury. A spectroscopic prognosis index distinguished between good outcome (n = 5) and poor outcome (n = 11) with one false negative (bad outcome after borderline MRS result) and no false positive results (100% specificity). The distinction was made with 90% sensitivity early (after 48 h) and became 100% later (by days 3 and 4). This compared with 50-75% specificity and 70-100% sensitivity based upon single clinical criteria. MRS performed sequentially in occipital gray matter provides useful objective information which can significantly enhance the ability to establish prognosis after near-drowning.

[Accident in the labor room. Monitoring responsibility of the midwife in relaxing baths before delivery]. / Ein Unglücksfall im Kreisssaal. Aufsichtspflicht der Hebamme bei Entspannungsbädern vor der Geburt.

During a relaxation bath, a 20-years old I-Para had an accident by submersion. In succession, both, mother and child, experienced irreparable cerebral injuries. While the counsel of prosecution pleads for manslaughter, forensic scientists and gynaecologists advise to discuss the inaccuracies in the law of midwife.

Drowning.

A body recovered from the water does not necessarily imply that death was due to drowning. The diagnosis of drowning is discussed together with the significance of the "diatom" and biochemical tests.

[Radiologic picture of the thorax in acute asphyxia caused by near drowning. A caseload contribution]. / Il quadro radiologico del torace nell'asfissia acuta da semi-annegamento. Contributo casistico.

One hundred-fifteen drowning and near-drowning patients were hospitalized in Jesolo and Mestre over the last 10 years. A correlation between radiological patterns and clinical features was thoroughly investigated by the authors. A close relationship was found between clinical findings and the X-ray pattern of the first radiography, taken immediately after the rescue. The longer the hospitalization (or when SNC is assessed) the less significant the correlation. According to the author's experience, prognosis is good when the first radiograph does not demonstrate any lesions. On the contrary, when lesions are seen on the first radiograph the patient is to be carefully monitored in order to treat every complication promptly, including ARDS (10% of all cases). Chest radiographs are also useful to explain autopsy findings. No typical radiological pattern was found: however, four signs were observed, which were very frequently associated-i.e., bilateral parenchymal shadows, pneumothorax, pneumopericardium, and gastrectasia. These findings appear to be characteristic of near-drowning.