OBJECTIVETo study possible correlation between matrix metalloproteinases (MMPs) activities and myocardial injury after asphyxia in neonatal Wistar rats.

METHODSixty neonatal Wistar rats (7 to 10 days old) were randomly divided into four groups: control group (group D); asphyxia groups A, B and C (1 day, 7 days, 14 days after asphyxia), every group had 15 rats. In the asphyxia groups, animal model was produced by normobaric asphyxia. Groups A, B and C were sacrificed on days 1, 7 and 14 days after asphyxia, and group D rats were sacrificed on the 7 th day. Then the heart blood was taken to tested the serum cTnI. The myocardial MMPs-3 and 9 activity was measured by using immunohistochemical assay. Histological sections of the hearts were stained with hematoxylin-eosin and myocardial histopathological scores were determined under an optical microscope. The amount of myocardial collagen was measured by means of chloramines T.

RESULTScTnI was significantly higher in group A (0.3680 +/- 0.40 ng/ml) than group D (0.0783 +/- 0.06 ng/ml) (P < 0.05), and was lower in group B (0.1889 +/- 0.15 ng/ml) but still significantly different from that of group D (P < 0.05), and declined to the normal level in group C (0.1338 +/- 0.07 ng/ml), but the difference between groups C and D was not significant (P > 0.05). Myocardial tissue MMPs-3 activity was transiently high in group A (0.1847 +/- 0.04), higher in group B (0.2780 +/- 0.05) as compared to group D (0.1213 +/- 0.03) (P < 0.05 for all). The activity of MMPs-3 increased earlier than that of MMPs-9. The amount of myocardial collagen of group B (38.94 +/- 0.67) and C (40.69 +/- 0.75) was significantly greater than that of group D (P < 0.05). Myoardial tissue MMPs-3 and MMPs-9 positively correlated with myocardial histopathological scores (r = 0.669, 0.667, P < 0.05) and myocardial collagen (r = 0.482, 0.679, P < 0.05).

CONCLUSIONSIn rats with asphyxia, there was an excess activation of myocardial MMPs-3 and MMPs-9 activities and secondary to which, the quantity of myocardial collagen increased. The injuries of myocardium may be closely associated with myocardial tissue MMPs. MMPs may be used to evaluate the severity of myocardial interstitial damage.

Animals ; Asphyxia ; metabolism ; pathology ; Collagen ; metabolism ; Disease Models, Animal ; Matrix Metalloproteinase 3 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Myocardium ; metabolism ; pathology ; Rats ; Rats, Wistar ; Troponin I ; blood

Benign idiopathic neonatal convulsion is a rare disorder which has no family history of convulsion and develops before and after the 5th day in a healthy full-term neonate. Its characteristics appear focal, or multifocal clonic seizures but rare tonic seizures lasting about several minutes. It reveals non-specific findings in neurologic examination, neuroimaging and EEG(electroencephalography) so that it should be differentiated from those diseases such as eletronic imbalance, inborn errors of metabolism, other neonatal epileptic syndromes. We report two healthy full-term female neonates presented with multifocal clonic seizures before and after the 5th day after birth. They had no family history of convulsion, fetal asphyxia, fetal and maternal problems and the neurologic examination and neuroimagings were normal. The convulsions were controlled by intravenous phenobarbital injection. They had no more convulsions ever since and showed normal development at the follow-up performed one year later. We experienced a rare disorder, benign neonatal convulsion in healthy full-term neonates. We hope this report will help its diagnosis and treatment and prevent unnecessary long- term anticonvulsant medication.
Asphyxia ; Epilepsy, Benign Neonatal ; Female ; Follow-Up Studies ; Humans ; Infant, Newborn ; Metabolism, Inborn Errors ; Neuroimaging ; Neurologic Examination ; Parturition ; Phenobarbital ; Seizures

Under hypoxia condition, microRNA （miRNA） can interact with transcription factors for regulating the cell metabolism, angiogenesis, erythropoiesis, cellular proliferation, differentiation and apoptosis. The biological processes above may play an important role in mechanical asphyxia death. This article reviews the regulating function of miRNA under hypoxia condition and the influence of hypoxia to biosynthesis of miRNA, which may provide some new ideas to the research of miRNA on determining the cause of mechanical asphyxia death in the field of forensic medicine.
Accidents ; Airway Obstruction/physiopathology* ; Apoptosis ; Asphyxia/pathology* ; Cause of Death ; Death ; Forensic Medicine ; Humans ; Hypoxia/physiopathology* ; MicroRNAs/metabolism* ; Oxygen

Pericardial fluid is a kind of serous fluid in pericardial cavity. Because blood undergoes postmortem changes such as autolysis and putrefaction, vitreous humor is limited,cerebrospinal fluid is easily mixed with blood, pericardial fluid, on the other hand, exists in a closed cavity and can be hardly contaminated by postmortem changes, and also is easily obtained. Pericardial fluid not only plays an important role in clinic practice, but also is widely applicable in forensic practice. This paper briefly presented the properties of pericardial fluid and its clinical significance. It reviewed biochemical changes in decedents died of heart diseases, drowning and asphyxia, and explored the significance in medico-legal investigation. Moreover, application of pericardial fluid in forensic serology, forensic toxicological analysis and other fields were also discussed. Pericardial fluid analysis may provide important information for determination of the cause of death with further investigation concerning forensic applicability of pericardial fluid.
Asphyxia/pathology* ; Atrial Natriuretic Factor/metabolism* ; Biomarkers/metabolism* ; Calcium/metabolism* ; Drowning/pathology* ; Forensic Pathology ; Heart Diseases/pathology* ; Humans ; L-Lactate Dehydrogenase/metabolism* ; Magnesium/metabolism* ; Myocardium/metabolism* ; Natriuretic Peptide, Brain/metabolism* ; Pericardium/metabolism* ; Postmortem Changes ; Troponin I/metabolism*

OBJECTIVETo study the application of positron emission tomography (PET) in detection of myocardial metabolism in pig ventricular fibrillation and asphyxiation cardiac arrest models after resuscitation.

METHODSThirty-two healthy miniature pigs were randomized into a ventricular fibrillation cardiac arrest (VFCA) group (n=16) and an asphyxiation cardiac arrest (ACA) group (n=16). Cardiac arrest (CA) was induced by programmed electric stimulation or endotracheal tube clamping followed by cardiopulmonary resuscitation (CPR) and defibrillation. At four hours and 24 h after spontaneous circulation was achieved, myocardial metabolism was assessed by PET. 18F-FDG myocardial uptake in PET was analyzed and the maximum standardized uptake value (SUVmax) was measured.

RESULTSSpontaneous circulation was 100% and 62.5% in VFCA group and ACA group, respectively. PET demonstrated that the myocardial metabolism injuries was more severe and widespread after ACA than after VFCA. The SUVmax was higher in VFCA group than in ACA group (P<0.01). In VFCA group, SUVmax at 24 h after spontaneous circulation increased to the level of baseline.

CONCLUSIONACA causes more severe cardiac metabolism injuries than VFCA. Myocardial dysfunction is associated with less successful resuscitation. Myocardial stunning does occur with VFCA but not with ACA.

Animals ; Asphyxia ; physiopathology ; Cardiopulmonary Resuscitation ; Gene Expression Regulation ; Heart Arrest ; etiology ; metabolism ; therapy ; Myocardium ; metabolism ; Positron-Emission Tomography ; methods ; Random Allocation ; Swine ; Ventricular Fibrillation ; metabolism

BACKGROUNDMorbidity and mortality after resuscitation largely depend on the recovery of brain function. Ventricular fibrillation cardiac arrest (VFCA) and asphyxial cardiac arrest (ACA) are the two most prevalent causes of sudden cardiac death. Up to now, most studies have focused on VFCA. However, results from the two models have been largely variable. So, it is necessary to characterize the features of postresuscitation cerebral metabolism of both models.

METHODSForty-four Wuzhishan miniature inbred pigs were randomly divided into three groups: 18 for VFCA group, ACA group, respectively, and other 8 for sham-operated group (SHAM). VFCA was induced by programmed electric stimulation, and ACA was induced by endotracheal tube clamping. After 8 min without treatment, standard cardiopulmonary resuscitation (CPR) was initiated. Following neurological deficit scores (NDS) were evaluated at 24 h after achievement of spontaneous circulation, cerebral metabolism showed as the maximum standardized uptake value (SUVmax) was measured by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. Levels of serum markers of brain injury, neuron specific enolase (NSE), and S100β were quantified with an enzyme-linked immunosorbent assay.

RESULTSCompared with VFCA group, fewer ACA animals achieved restoration of spontaneous circulation (61.1% vs. 94.4%, P < 0.01) and survived 24-h after resuscitation (38.9% vs. 77.8%, P < 0.01) with worse neurological outcome (NDS: 244.3 ± 15.3 vs. 168.8 ± 9.71, P < 0.01). The CPR duration of ACA group was longer than that of VFCA group (8.1 ± 1.2 min vs. 4.5 ± 1.1 min, P < 0.01). Cerebral energy metabolism showed as SUVmax in ACA was lower than in VFCA (P < 0.05 or P < 0.01). Higher serum biomarkers of brain damage (NSE, S100β) were found in ACA than VFCA after resuscitation (P < 0.01).

CONCLUSIONSCompared with VFCA, ACA causes more severe cerebral metabolism injuries with less successful resuscitation and worse neurological outcome.

Animals ; Asphyxia ; complications ; physiopathology ; Brain ; metabolism ; Cardiopulmonary Resuscitation ; Heart Arrest ; metabolism ; pathology ; therapy ; Positron-Emission Tomography ; Swine ; Ventricular Fibrillation ; metabolism ; pathology ; therapy

OBJECTIVE: To observe the postmortem degradation process in rat myocardium and skeletal muscle using Fourier transform infrared (FTIR) spectroscopy and to provide a new method for estimating postmortem interval (PMI). METHODS: Left ventricle and skeletal muscles of rats dying of mechanical asphyxiated were sampled at different PMIs. The changes of different chemical functional group in the myocardium and skeletal muscle samples were measured by FTIR spectroscopy. The different absorbance (A) ratios of peaks were calculated and the curve estimation analysis between absorbance ratios (x) and PMI (y) were performed to establish six mathematical models. RESULTS: FTIR spectral absorption peak of rat myocardium and skeletal muscle showed three changes: increase, decrease and stable. The cubic model function showed the strongest correlation coefficient. The A1080/A1396 ratio of skeletal muscle showed the strongest correlation coefficient (r = 0.832) with more accurate determination of PMI. CONCLUSION FYIR spectroscopy can be potentially used as an effective method for estimating PMI in forensic practice using myocardium and skeletal muscle.
Animals ; Asphyxia/metabolism* ; Forensic Pathology/methods* ; Male ; Muscle, Skeletal/metabolism* ; Myocardium/metabolism* ; Postmortem Changes ; Rats ; Rats, Sprague-Dawley ; Spectroscopy, Fourier Transform Infrared ; Time Factors

OBJECTIVETo investigate, from cytoprotein and molecular levels, the action mechanism of astragalus injection (ASI) on the signal conduction of human renal tubular cells (HK-2) injury induced by neonatal postasphyxial-serum (NPS), whether it is through activating the nuclear factor kappaB (NF-kappaB) signaling pathway.

METHODSTaking HK-2 as the target cell and the 20% NPS as the attacking factor, the experiment was conducted by dividing the target cells into two groups before attacking, the blank control group and the ASI pretreated group. The nuclear translocation of NF-kappaB was detected by confocal microscopy with indirect immunofluorescence stain, and the amount of NF-kappaB inhibitor subunit (I-kappaBalpha) was detected by Western blot before attacking. The detections were repeated at various time points in the experiment, i.e., 15 min, 1 h and 2 h after attacking, respectively.

RESULTSBefore attacking, the nuclear translocation of NF-kappaB and the amount of I-kappaBalpha were not different in the two groups. But the former increased and the latter decreased significantly in the ASI group at all the time points after attacking with the topmost changes presented at 1 h after attacking, and significantly different to those in the control group at corresponding time

CONCLUSIONASI pretreatment could inhibit the activation of NF-kappaB induced by postasphyxial-serum.

Apoptosis ; Asphyxia Neonatorum ; blood ; Astragalus Plant ; Cell Line ; Humans ; I-kappa B Proteins ; metabolism ; Infant, Newborn ; Kidney Tubules ; cytology ; metabolism ; NF-KappaB Inhibitor alpha ; Signal Transduction

OBJECTIVE: The content changes of energy substances in the cardiac muscle of rat killed by different manners were investigated to elucidate evidence that can be used to determine the modes of death and postmortem interval. METHODS: One hundred and eighty rats were randomly allocated into 3 groups and killed by bleeding, suffocating, and neck breaking, respectively. The contents of ATP, ADP, and AMP in the cardiac muscle of rats killed by the different manners at different death intervals (0, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 18, and 24 h) were measured by HPLC. RESULTS: There were significant differences observed in the contents of ATP and AMP in the rats' cardiac muscle in different groups at most of the intervals (P < 0.05) and at all of the intervals within the same group (P < 0.01), but no differences were found in the ADP contents in any of the group at most of the intervals. CONCLUSION The content changes of energy substances (ATP and AMP) in the cardiac muscle of dead rats may provide a basis for determination of the death manners and postmortem intervals.
Adenosine Diphosphate/metabolism* ; Adenosine Monophosphate/metabolism* ; Adenosine Triphosphate/metabolism* ; Animals ; Asphyxia/metabolism* ; Cause of Death ; Cervical Vertebrae/injuries* ; Chromatography, High Pressure Liquid ; Female ; Male ; Myocardium/pathology* ; Postmortem Changes ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Shock, Hemorrhagic/metabolism* ; Time Factors

OBJECTIVETo study the role of serum from asphyxiated neonates in the inducement of human renal proximal tubular epithelial cells (HK-2) adhesion to neutrophils and possible mechanisms.

METHODSHK-2 cells were cultured randomly with 20% serum from neonates (1, 3, and 7 days after asphyxia), pyrrolidine dithiocarbamate (PDTC) or placebo. The activity of myeloperoxidase (MPO), an indicator of adhesion ability of HK-2 cells to neutrophils in suspensions, was detected by the biochemistry assay. Intercellular adhesion molecule-1 (ICAM-1) and nuclear factor-kappaB (NF-kappaB) of HK-2 cells were examined with the immunohistochemical staining.

RESULTSThe expression of MPO in the post-asphyxial 1-day serum treatment group were significantly higher than that in the PDTC treatment and the control groups as well as the post-asphyxial 3 and 7-day serum treatment groups (P<0.01). The expression of ICAM-1 and NF-kappaB in the post-asphyxial 1-day serum treatment group was also significantly higher than that in the other groups (P<0.01).

CONCLUSIONSSerum from asphyxiated neonates can induce HK-2 cell adhesion to neutrophils, possibly through activating NF-kappaB and increasing the synthesis and expression of ICAM-1 on the surface of renal tubular epithelial cells.

Asphyxia Neonatorum ; blood ; complications ; Cell Adhesion ; Cells, Cultured ; Humans ; Infant, Newborn ; Intercellular Adhesion Molecule-1 ; analysis ; biosynthesis ; Kidney Tubules ; pathology ; NF-kappa B ; analysis ; metabolism ; Neutrophils ; physiology