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The tribe Ranunculeae, Ranunculaceae, comprising 19 genera widely distributed all over the world. Although a large number of Sanger sequencing-based molecular phylogenetic studies have been published, very few studies have been performed on using genomic data to infer phylogenetic relationships within Ranunculeae. In this study, the complete plastid genomes of nine species (eleven samples) from Ceratocephala, Halerpestes, and Ranunculus were de novo assembled using a next-generation sequencing method. Previously published plastomes of Oxygraphis and other related genera of the family were downloaded from GenBank for comparative analysis. The complete plastome of each Ranunculeae species has 112 genes in total, including 78 protein-coding genes, 30 transfer RNA genes, and four ribosomal RNA genes. The plastome structure of Ranunculeae samples is conserved in gene order and arrangement. There are no inverted repeat (IR) region expansions and only one IR contraction was found in the tested samples. This study also compared plastome sequences across all the samples in gene collinearity, codon usage, RNA editing sites, nucleotide variability, simple sequence repeats, and positive selection sites. Phylogeny of the available Ranunculeae species was inferred by the plastome data using maximum-likelihood and Bayesian inference methods, and data partitioning strategies were tested. The phylogenetic relationships were better resolved compared to previous studies based on Sanger sequencing methods, showing the potential value of the plastome data in inferring the phylogeny of the tribe.
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Genoma de Plastidios , Ranunculaceae , Filogenia , Ranunculaceae/genética , Teorema de Bayes , Genoma de Plastidios/genética , NucleótidosRESUMEN
The competitive relationship is one of the important studies in population ecology. In this paper, we investigate the dynamical behaviors of a two-species Lotka-Volterra competition system in which intrinsic rates of increase are governed by the Ornstein-Uhlenbeck process. First, we prove the existence and uniqueness of the global solution of the model. Second, the extinction of populations is discussed. Moreover, a sufficient condition for the existence of the stationary distribution in the system is obtained, and, further, the formulas for the mean and the covariance of the probability density function of the corresponding linearized system near the equilibrium point are obtained. Finally, numerical simulations are applied to verify the theoretical results.
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The coupled Schrödinger-Korteweg-de Vries equation is a critical system of in nonlinear evolution equations. It describes various processes in dusty plasma, such as Langmuir waves, dust-acoustic waves, and electromagnetic waves. This paper uses the generalized coupled trial equation method to solve the equation. By the complete discrimination system for polynomial, a series of exact traveling wave solutions are obtained, including discontinuous periodic solutions, solitary wave solutions, and Jacobian elliptical function solutions. In addition, to determine the existence of the solutions and understand their properties, we draw three-dimensional images of the modules of the solutions with Mathematica. We obtain more comprehensive and accurate solutions than previous studies, and the results give the system more profound physical significance.
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The utility of transcriptome data in plant phylogenetics has gained popularity in recent years. However, because RNA degrades much more easily than DNA, the logistics of obtaining fresh tissues has become a major limiting factor for widely applying this method. Here, we used Ranunculaceae to test whether silica-dried plant tissues could be used for RNA extraction and subsequent phylogenomic studies. We sequenced 27 transcriptomes, 21 from silica gel-dried (SD-samples) and six from liquid nitrogen-preserved (LN-samples) leaf tissues, and downloaded 27 additional transcriptomes from GenBank. Our results showed that although the LN-samples produced slightly better reads than the SD-samples, there were no significant differences in RNA quality and quantity, assembled contig lengths and numbers, and BUSCO comparisons between two treatments. Using these data, we conducted phylogenomic analyses, including concatenated- and coalescent-based phylogenetic reconstruction, molecular dating, coalescent simulation, phylogenetic network estimation, and whole genome duplication (WGD) inference. The resulting phylogeny was consistent with previous studies with higher resolution and statistical support. The 11 core Ranunculaceae tribes grouped into two chromosome type clades (T- and R-types), with high support. Discordance among gene trees is likely due to hybridization and introgression, ancient genetic polymorphism and incomplete lineage sorting. Our results strongly support one ancient hybridization event within the R-type clade and three WGD events in Ranunculales. Evolution of the three Ranunculaceae chromosome types is likely not directly related to WGD events. By clearly resolving the Ranunculaceae phylogeny, we demonstrated that SD-samples can be used for RNA-seq and phylotranscriptomic studies of angiosperms.
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Ranunculaceae , Filogenia , Hojas de la Planta/genética , ARN , Gel de SíliceRESUMEN
In order to improve the willingness of continuous use of mobile social network information services, this study combines user behavior perception to analyze the continuous use of mobile social network information services and proposes a data coverage optimization strategy based on service quality perception. Furthermore, this study measures participants' regional preferences based on the duration of participants in the perceptual region and the number of historical perceptual tasks completed on the perceptual region. In addition, this study designs a perceptual data coverage optimization algorithm to optimize the perceptual data coverage and ensure the real-time validity of the perceptual data. Through algorithm research and systematic evaluation, it can be seen that the continuous use willingness system of mobile social network information service based on user behavior perception can basically meet the actual needs.
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Algoritmos , Intención , Humanos , Servicios de Información , Percepción , Red SocialRESUMEN
[This corrects the article DOI: 10.3389/fgene.2021.730495.].
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The evening primrose family, Onagraceae, is a well defined family of the order Myrtales, comprising 22 genera widely distributed from boreal to tropical areas. In this study, we report and characterize the complete chloroplast genome sequences of 13 species in Circaea, Chamaenerion, and Epilobium using a next-generation sequencing method. We also retrieved chloroplast sequences from two other Onagraceae genera to characterize the chloroplast genome of the family. The complete chloroplast genomes of Onagraceae encoded an identical set of 112 genes (with exclusion of duplication), including 78 protein-coding genes, 30 transfer RNAs, and four ribosomal RNAs. The chloroplast genomes are basically conserved in gene arrangement across the family. However, a large segment of inversion was detected in the large single copy region of all the samples of Oenothera subsect. Oenothera. Two kinds of inverted repeat (IR) region expansion were found in Oenothera, Chamaenerion, and Epilobium samples. We also compared chloroplast genomes across the Onagraceae samples in some features, including nucleotide content, codon usage, RNA editing sites, and simple sequence repeats (SSRs). Phylogeny was inferred by the chloroplast genome data using maximum-likelihood (ML) and Bayesian inference methods. The generic relationship of Onagraceae was well resolved by the complete chloroplast genome sequences, showing potential value in inferring phylogeny within the family. Phylogenetic relationship in Oenothera was better resolved than other densely sampled genera, such as Circaea and Epilobium. Chloroplast genomes of Oenothera subsect. Oenothera, which are biparental inheritated, share a syndrome of characteristics that deviate from primitive pattern of the family, including slightly expanded inverted repeat region, intron loss in clpP, and presence of the inversion.
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Diffuse axonal injury (DAI) is one of the most common and severe pathological consequences of traumatic brain injury (TBI). The molecular mechanism of DAI is highly complicated and still elusive, yet a clear understanding is crucial for the diagnosis, treatment, and prognosis of DAI. In our study, we used rats to establish a DAI model and applied isobaric tags for relative and absolute quantitation (iTRAQ) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis to identify differentially expressed proteins (DEPs) in the corpus callosum. As a result, a total of 514 proteins showed differential expression between the injury groups and the control. Among these DEPs, 14 common DEPs were present at all seven time points postinjury (1, 3, 6, 12, 24, 48, and 72 h). Next, bioinformatic analysis was performed to elucidate the pathogenesis of DAI, which was found to possibly involve calcium ion-regulatory proteins (e.g., calsenilin and ryanodine receptor 2), cytoskeleton organization (e.g., peripherin, NFL, NFM, and NFH), apoptotic processes (e.g., calsenilin and protein kinase C delta type), and inflammatory response proteins (e.g., complement C3 and C-reactive protein). Moreover, peripherin and calsenilin were successfully confirmed by western blotting to be significantly upregulated during DAI, and immunohistochemical (IHC) analysis revealed that their expression increased and could be observed in axons after injury, thus indicating their potential as DAI biomarkers. Our experiments not only provide insight into the molecular mechanisms of axonal injury in rats during DAI but also give clinicians and pathologists important reference data for the diagnosis of DAI. Our findings may expand the list of DAI biomarkers and improve the postmortem diagnostic rate of DAI.
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Lesión Axonal Difusa/diagnóstico , Lesión Axonal Difusa/metabolismo , Lesión Axonal Difusa/patología , Animales , Axones/metabolismo , Biomarcadores/metabolismo , Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/patología , Cromatografía Liquida/métodos , Biología Computacional/métodos , Cuerpo Calloso/metabolismo , Femenino , Pronóstico , Proteómica/métodos , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem/métodosRESUMEN
Primary intraventricular hemorrhage (PIVH) is a rare type of stroke defined as bleeding within the ventricles of the brain without any associated parenchymal hemorrhage. Here, we reported two cases of sudden death due to PIVH. One of the patients was found dead under a highway bridge without witnesses, and the other patient was hospitalized with hemorrhage in the ventricular system, as revealed by a head computed tomography scan. In these two patients, autopsy and macroscopic examination only showed hemorrhages in the ventricular system without any traumatic brain injury or other intraparenchymal hemorrhage. The sources of bleeding for both patients were ultimately confirmed as ruptured brain arteriovenous malformations located in the subventricular zone. We reported these cases to broaden our understanding of sudden death associated with PIVH, especially when caused by brain arteriovenous malformation. We also summarized the essential details of the diagnoses and available technical methods for PIVH cases.
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Hemorragia Cerebral/patología , Muerte Súbita/etiología , Malformaciones Arteriovenosas Intracraneales/patología , Actinas/metabolismo , Adulto , Humanos , Malformaciones Arteriovenosas Intracraneales/metabolismo , Ventrículos Laterales/patología , Masculino , Miocitos del Músculo Liso/metabolismo , Rotura EspontáneaRESUMEN
CONTEXT: Terbufos (TBF) is a class Ia (extremely hazardous) organophosphate pesticide (OP) and its distribution in industrialized countries has been severely restricted. Thus, acute occupational poisoning is rather uncommon. However, it still occurs in rural areas of some developing countries, where the sale of TBF is not controlled and its use is thus not properly regulated. We report a case of a 43-year-old female farmer who died after applying TBF granules. CASE: The patient died within 3 h after applying 20 bags of 5% TBF granules (900 g per bag). Investigation showed that her personal protective equipment (PPE) did not provide effective protection against dermal and inhalational exposure. Postmortem analysis revealed extremely low red blood cell acetylcholinesterase activity. Toxicological analysis of TBF showed 1.45 × 10-2 µg/ml in the heart blood and 0.17 µg/g in the liver. DISCUSSIONS: This patient died as a result of toxicity from dermal and inhalational exposure to TBF. Over-application, improper equipment, inadequate and defective PPE, and lack of hygienic precautions were all contributing factors. CONCLUSIONS: TBF is a highly toxic OP. Inadequate regulatory control, improper environmental application, and ineffective PPE resulted in a fatal human exposure.
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Insecticidas/envenenamiento , Exposición Profesional/efectos adversos , Intoxicación por Organofosfatos/etiología , Compuestos Organotiofosforados/envenenamiento , Acetilcolinesterasa/sangre , Adulto , Eritrocitos/enzimología , Resultado Fatal , Femenino , Humanos , Exposición por Inhalación , Hígado/química , Miocardio/química , Intoxicación por Organofosfatos/enzimología , Ropa de Protección , Absorción CutáneaRESUMEN
Malignant hyperthermia (MH) is an autosomal dominant disorder characterized by abnormal calcium homeostasis in skeletal muscles in response to triggering agents. Autopsy, morphology, and genetic analysis were performed on a 19-year-old man who died rapidly after exposure to sevoflurane during maxillofacial surgery. Muscle spasm around the operation area and limb rigidity occurred and renal tubules full of myoglobin casts were observed by microscopy. Ultrastructural changes in the skeletal muscles and the myocardium were detected by transmission electron microscopy (TEM). Genetic analysis disclosed a ryanodine receptor type 1 (RYR1) gene mutation and a nucleoide mutation in chromosome 19q (G1021A) in the deceased and his father. According to the fore mentioned results, the relationship between the cause of death and MH was confirmed. Thus, genetic analysis can be an important procedure in diagnosing MH.
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Muerte Súbita/etiología , Hipertermia Maligna/genética , Mutación , Canal Liberador de Calcio Receptor de Rianodina/genética , Sustitución de Aminoácidos , Anestésicos por Inhalación/efectos adversos , Pruebas Genéticas , Humanos , Masculino , Éteres Metílicos/efectos adversos , Microscopía Electrónica de Transmisión , Sevoflurano , Adulto JovenRESUMEN
BACKGROUND: Intravascular large B-cell lymphoma (IVLBCL) is a subtype of diffuse large B-cell lymphoma (DLBCL) that is rare and highly aggressive and that may progressively involve many organs. CNS (central nervous system), BM (bone marrow) and skin are the most common systems involved. To date, only 2 cases of IVLBCL involving the thyroid have been reported. CASE PRESENTATION: Here, we report a case of IVLBCL involving the thyroid and accompanied by bilateral nodular goiter. In this case, a thyroid mass was identified in a physical examination of a 68-year-old male who initially presented with dyspnea accompanied by intermittent headache for approximately 1 month. Computed tomography scans revealed that the left lobar thyroid was occupied by a large, slightly lower density mass (5.8 × 4.7 × 8.4 cm). However, the patient had no hyperthyroidism or hoarseness. Levels of thyroid hormones and anti-thyroid autoantibodies in the serum were normal preoperatively. Thyroid mass resection was performed to establish a diagnosis and to relieve symptoms. CONCLUSIONS: Pathological results of the surgical specimen revealed that large atypical lymphoma cells filled the capillaries in the lesion area. Immunohistochemical staining revealed that the large-sized tumor cells were positive for CD20, PAX-5, MUM-1 and BCL-2, and were negative for CD3, CD5, CD43, CD10, CD23, CyclinD1, CD138, CD30, ALK, CD56, MPO, S-100, TTF-1, TG (thyroglobulin) and CT (calcitonin). The Ki-67 index was estimated to be approximately 85%. The patient was subsequently diagnosed as "Classical" IVLBCL non-germinal center B-cell type. The patient declined chemotherapy and died in the fifth month after operation.
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Bocio Nodular/etiología , Linfoma de Células B Grandes Difuso/patología , Anciano , Humanos , MasculinoRESUMEN
INTRODUCTION: Atrioventricular node (AVN) contusion usually results in cardiogenic shock and arrhythmia and is a rare but fatal condition. The condition is difficult to diagnose and easily overlooked because it develops rapidly and is asymptomatic. We here report 3 cases that demonstrate blunt chest impact and hemorrhages of the posterior atrioventricular junction, eventually result in death. CLINICAL FINDINGS: Autopsy and histological examination were performed on all cases. External inspection revealed bruises in the hearts and fractures in the sternum and ribs. However, histological examinations were conclusive and showed cardiac contusion on the surface of the posterior atrioventricular junction of the individuals, and the death was due to the AVN contusion. The position of the AVN on the heart surface is determined by detailed examinations via an autopsy and microscopic, both of which are critical in the certification of cause of death. CONCLUSION: The report is intended to raise our understanding and make forensic pathologists aware of the surface of the posterior atrioventricular junction.
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Nodo Atrioventricular/lesiones , Contusiones/complicaciones , Muerte Súbita Cardíaca/etiología , Adolescente , Adulto , Humanos , Masculino , Adulto JovenRESUMEN
BACKGROUND: Branchial cleft anomalies constitute a frequently encountered and commonly non-lethal disease in otolaryngology, and result from aberrant embryonic development. The third branchial cleft fistula is one of the four known specific types of branchial cleft anomalies, and always presents as recurrent neck abscess and suppurative thyroiditis. Here, we report an unexpected death due to severe neck infection following a third branchial cleft fistula. CASE PRESENTATION: A 19-year-old man was sent to the hospital with a 1-week history of recurrent left-sided neck abscess, and was scheduled for incision and drainage of the abscess. However, before the surgery was performed, the man's condition deteriorated and he died. A review of his medical history showed that he had undergone a previous incision and drainage for a neck abscess 2 years ago. Postmortem examination revealed that the fatal neck abscess was induced by a third branchial cleft fistula. CONCLUSIONS: We conclude that a histopathological examination of neck tissue combined with a detailed review of medical history and examination of ultrasonographic and CT images can provide a rapid and accurate diagnosis of third branchial cleft fistula. This common, non-lethal disease can potentially lead to death if the neck infection is not properly diagnosed and treated. In medico-legal practice, medical examiners should be aware of this condition, as this knowledge would be important in the diagnosis of the cause of death.
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Absceso/microbiología , Región Branquial/anomalías , Anomalías Craneofaciales/complicaciones , Fístula Cutánea/complicaciones , Enfermedades Faríngeas/complicaciones , Tiroiditis Supurativa/microbiología , Absceso/diagnóstico , Absceso/cirugía , Autopsia , Región Branquial/diagnóstico por imagen , Anomalías Craneofaciales/diagnóstico , Anomalías Craneofaciales/diagnóstico por imagen , Fístula Cutánea/diagnóstico , Fístula Cutánea/diagnóstico por imagen , Progresión de la Enfermedad , Drenaje , Resultado Fatal , Humanos , Inmunohistoquímica , Masculino , Enfermedades Faríngeas/diagnóstico , Enfermedades Faríngeas/diagnóstico por imagen , Recurrencia , Choque Séptico/microbiología , Tiroiditis Supurativa/diagnóstico , Tiroiditis Supurativa/cirugía , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía , Adulto JovenRESUMEN
Vascular involvement is a well-recognized manifestation of neurofibromatosis type 1 (NF1) which has the potential to be fatal when disrupted. We here present a case of sudden death due to the fatal arterial rupture resulted from infiltration of the neurofibromas. A 42-year-old man who suffered from NF1 presented a 1-h history of sudden onset of pain in his right cervical region. His condition worsened and became unconscious on his way to the emergency room. Despite resuscitation efforts, he died 30min later without regaining consciousness. Autopsy examination showed that a neurofibroma located around the right internal carotid artery, confirmed immunohistochemically with S-100, vimentin and CD34. Furthermore, proliferation of spindle cells positive for S-100 was seen in the wall of right internal carotid artery, which was disrupted and resulted in a hemorrhage. These findings suggest that the artery was disrupted by neurofibromas in the vascular wall, which led to fragility of the vessel. On the basis of these findings, we concluded that the cause of death was asphyxia resulting from airway obstruction compressed by the hematoma due to the arterial rupture. As the locality of the neurofibroma and hemorrhage were closed to the carotid baroreflex, we considered another possible mechanism of his sudden death, which could be cardiac inhibition induced by vagal stimulation. We hope this case will increase recognition of NF-1 vasculopathy when encountering any sudden death in NF1 patients.
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Arteria Carótida Interna/fisiopatología , Muerte Súbita , Neurofibromatosis 1 , Rotura Espontánea/complicaciones , Adulto , Autopsia , Patologia Forense , Humanos , Masculino , Neurofibromatosis 1/fisiopatologíaRESUMEN
In emergency departments, intoxication with the muscle relaxant succinylcholine (SUX) often leads to a potentially lethal respiratory paralysis or other deleterious side effects. However, homicide cases with SUX poisoning are very rare because the toxic or lethal concentration ranges of SUX have not yet been determined. We described three uncommon homicide cases due to acute poisoning by darts contaminated with SUX. All the victims died quickly (less than 30 min) after being shot by an especially designed dart gun. Succinylmonocholine (SMC), a metabolite of SUX, was used as a marker to detect the latter. HPLC-MS/MS analysis demonstrated the presence of SUX in the droplet residues of the darts and SMC in the blood and urine in all cases. SMC concentrations of 0.45, 14.0, and 17.9 ng/ml were detected in the victims' blood and 259.0 ng/ml in the urine from the third case. The main pathological changes consisted of hemorrhage of the injured soft tissues, visceral congestion, severe pulmonary edema, and multifocal petechial hemorrhage of the heart and lungs. Taken together, the findings supported a diagnosis of fatal SUX poisoning. Futhermore, our study provided a reference for the lethal concentrations of SUX poisoning.
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Homicidio , Fármacos Neuromusculares Despolarizantes/envenenamiento , Succinilcolina/envenenamiento , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Cromatografía Líquida de Alta Presión , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Fármacos Neuromusculares Despolarizantes/análisis , Succinilcolina/análogos & derivados , Succinilcolina/análisis , Succinilcolina/sangre , Succinilcolina/orina , Heridas PunzantesRESUMEN
A 59-year-old man was struck in the abdomen and later presented to the emergency room. His blood pressure dropped and eventually died 16h post trauma and just before emergency exploratory laparotomy. Autopsy revealed two polycystic kidneys and a giant polycystic liver with two ruptures. Blood (2225g) was observed in the peritoneum and the body-surface injury was minor. Genetic testing was performed to confirm that the man had an autosomal dominant polycystic kidney disease (ADPKD) complicated by polycystic liver disease (PLD). Autopsy, histopathology and medical history showed that the cause of death was the ruptures of liver cysts due to trauma. In this communication, we describe a fatal case and hope to increase awareness and recognition of PLD and ADPKD. We also wish to indicate that due to the fragile condition of liver cysts, trauma should be considered even if the body-surface injury is minor in fatal cases of PLD patient with a traumatic history.
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Traumatismos Abdominales/complicaciones , Quistes/patología , Hepatopatías/patología , Riñón Poliquístico Autosómico Dominante/patología , Rotura/etiología , Resultado Fatal , Hemorragia/etiología , Hemorragia/patología , Humanos , Masculino , Persona de Mediana Edad , Peritoneo/patologíaRESUMEN
Traumatic coronary pseudoaneurysm has been described to be mainly associated to iatrogenic lesion of the coronary arteries. However, chest-stab-wound-related coronary pseudoaneurysm caused by isolated partial incision of a coronary artery giving rise to fatal delayed cardiac tamponade is very rare. We describe an autopsy case in which this potentially fatal complication developed 8 days later after a thoracic stab wound. Unfortunately, the imaging examination failed to detect this defect during hospitalization. Postmortem examination revealed that the posterior wall of the left anterior descending coronary artery was intact but that the anterior wall was incised, forming a micropseudoaneurysm which had ruptured. This case highlights that isolated coronary artery injuries must be considered in any patient with a penetrating wound to the thorax, and coronary pseudoaneurysms should not be missed in these patients.
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Aneurisma Falso/etiología , Aneurisma Roto/etiología , Taponamiento Cardíaco/etiología , Aneurisma Coronario/etiología , Vasos Coronarios/lesiones , Lesiones Cardíacas/etiología , Lesiones del Sistema Vascular/etiología , Heridas Punzantes/etiología , Adolescente , Aneurisma Falso/patología , Aneurisma Roto/patología , Autopsia , Taponamiento Cardíaco/patología , Causas de Muerte , Aneurisma Coronario/patología , Vasos Coronarios/patología , Errores Diagnósticos , Resultado Fatal , Lesiones Cardíacas/patología , Humanos , Masculino , Factores de Tiempo , Lesiones del Sistema Vascular/patología , Heridas Punzantes/patologíaRESUMEN
Vaginal tightening is a kind of esthetic surgery aimed at enhancing sexual satisfaction during intercourse. Although the injective vaginal tightening procedure is informal, there are already some reports of its application. But pulmonary embolism is a really rare therapeutic complication of this procedure. We report a case of death due to the non-thrombotic pulmonary embolism as a consequence of illegal cosmetic vaginal-tightening procedure using polyacrylamide hydrogel. A 34-year-old woman was hospitalized with paroxysmal abdominal cramps and diarrhea as initial symptoms, while she concealed the genital cosmetic surgery history. Respiratory distress presented only 1.5h before she died. The result of autopsy revealed the cause of death as pulmonary embolism due to the hydrogel which was injected into her vaginal wall. The emboli were confirmed as polyacrylamide hydrogel by Alcian-blue stain and the Fourier transform infrared scanning. It is suggested that pulmonary embolism should not be discarded in the expertise of deaths following cosmetic implant surgeries. It broadens our understanding about death associated with esthetic genital procedures and informs clinicians and medical examiners of the potential death of this type. And detailed investigations of previous medical and surgical history will always play a critical role in the certification of cause of death.