Fatal human herpes virus 6B myocarditis: Postmortem diagnosis of HHV-6B based on CD134+ T-cell tropism.

Human herpes virus 6 (HHV-6) is one of the most important pathogens of viral myocarditis, and is often responsible for sudden death in young adults. A 59-year-old immunocompetent man died of serious lymphocytic myocarditis, and his peripheral blood sample showed HHV-6 DNAemia. Recently, HHV-6 cell entry and reactivation have been suggested to be regulated by the expression of specific CD receptors on T lymphocytes. Here, we report a case of HHV-6 myocarditis diagnosed using an experimental method focused on this unique cell tropism. The interaction between HHV-6 and CD expression was assessed using an immunofluorescence assay. Colocalization between HHV-6B and CD134 was detected in lymphocytes infiltrating the myocardium, which was highly suggestive of an active HHV-6B infection and could be a useful criterion for postmortem diagnosis of HHV-6B myocarditis in the acute phase.

Pre-administration of low-dose methamphetamine enhances movement and neural activity after high-dose methamphetamine administration in the striatum.

Methamphetamine (METH) is a powerful stimulant drug of abuse, with potent addictive and neurotoxic properties. In this study, the effects of low-dose METH administration prior to high-dose METH administration on movement and neural activity in rats were examined. Rats were administered low-dose (1 mg/kg/day) METH or saline for 5 consecutive days (m5 and s5, respectively), followed by high-dose (10 mg/kg) METH on day 6 (m5M and s5M, respectively). An accelerometer was used to evaluate the frequency of movement when rats were placed in a cage for 30 min. The expression of c-fos, a neuronal activity marker, in the striatum was analyzed using immunohistochemistry. Striatal protein expression of neuronal markers, including vesicular glutamate transporter 2 (VGLUT2), glutamate decarboxylase 67 (GAD67), tyrosine hydroxylase (TH), tryptophan hydroxylase 2 (TPH2), and the glial marker, glial fibrillary acidic protein (GFAP), was analyzed by western blot. Accelerometer counts and the numbers of c-fos-positive cells in the striatum were significantly higher in the m5M than in the s5, m5, and s5M groups. The expression levels of VGLUT2 and GAD67, but not those of TH, TPH2, or GFAP, were significantly higher in the m5M than in the s5M group. These results suggest that pre-administration of low-dose METH prior to high-dose METH administration in rats may alter excitatory and inhibitory neurons in the striatum, thereby affecting movement and neural activity in rats.

An autopsy report of accidental burial in a beach sand hole.

We present a 23-year-old married couple who died by accidental burial in a beach sand hole. The victims fell into a hole that had been covered with a plastic sheet, and were buried suddenly by sand that had been piled on the top of the sheet. At autopsy, facial congestion; petechial hemorrhages in the conjunctivae and the oral mucosa; skin petechiae at the face, neck and upper chest; congestion and hemorrhages in the cervical lymph nodes; and some minor hemorrhages in the cervical muscles were found in both victims. Little sand was evident in the airway, while sand debris was found in the oral cavity. Prior reports suggest that aspiration of sand is a major contributing factor in asphyxia after accidental burials. However, neck and chest compression and face coverage by sand masses could induce lethal asphyxia without airway obstruction caused by sand aspiration. Asphyxia was deemed to be the cause of death in both individuals and was considered to result from chest compression by sand. In addition, compression of the neck may also have contributed to asphyxia. In this instance, the sand beach hole was excavated for recreational purposes. The potentially life-threatening implications of beach sand hole excavations should be recognized and highlighted to prevent lethal accidents such as those described in this report.

Hemophagocytic Lymphohistiocytosis in a Fatal Case of Severe Fever with Thrombocytopenia Syndrome.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease caused by a novel Bunyavirus with a high mortality rate. We herein report a fatal case of an 86-year-old woman with SFTS complaining of a fever, fatigue, and bicytopenia. Her condition deteriorated with rapid progression of bleeding tendency, disturbance of consciousness, and multiple organ failure leading to death on Day 6 of her illness. The histopathological findings in the autopsy revealed marked infiltration of macrophages with hemophagocytosis in the bone marrow, liver, and spleen leading to a diagnosis of hemophagocytic lymphohistiocytosis (HLH). HLH might be a critical pathogenesis in fatal cases of SFTS.

Deletion of N-myc downstream-regulated gene 2 attenuates reactive astrogliosis and inflammatory response in a mouse model of cortical stab injury.

N-myc downstream-regulated gene 2 (Ndrg2) is a differentiation- and stress-associated molecule predominantly expressed in astrocytes in the CNS. In this study, we examined the expression and the role of Ndrg2 after cortical stab injury. We observed that Ndrg2 expression was elevated in astrocytes surrounding the wounded area as early as day 1 after injury in wild-type mice. Deletion of Ndrg2 resulted in lower induction of reactive astroglial and microglial markers in the injured cortex. Histological analysis showed reduced levels of hypertrophic changes in astrocytes, accumulation of microglia, and neuronal death in Ndrg2(-/-) mice after injury. Furthermore, activation of the IL-6/signal transducer and activator of transcription 3 (STAT3) pathway, including the expression of IL-6 family cytokines and phosphorylation of STAT3, was markedly reduced in Ndrg2(-/-) mice after injury. In a culture system, both of Il6 and Gfap were up-regulated in wild-type astrocytes treated with forskolin. Deletion of Ndrg2 attenuated induction of these genes, but did not alter proliferation or migration of astrocytes. Adenovirus-mediated reexpression of Ndrg2 rescued the reduction of IL-6 expression after forskolin stimulation. These findings suggest that Ndrg2 plays a key role in reactive astrogliosis after cortical stab injury through a mechanism involving the positive regulation of IL-6/STAT3 signaling.

Sudden death of an infant with coronary involvement due to Takayasu arteritis.

We present an unusual case of sudden death of an 8-month-old female infant with coronary involvement due to Takayasu arteritis. She had been thought to be healthy, but died after presenting to a hospital with complains of vomiting. At autopsy, the aorta and its main branches were thickened and stenotic, with the abdominal aorta below the level of the orifice of renal arteries most severely affected. The ascending aorta was thickened and showed ostial stenosis in the coronary arteries bilaterally. The proximal segment of the left and right coronary arteries showed approximately 60% and over 90% occlusion, respectively. Microscopically, the intima was thickened due to an increase of intimal cells and fibers, and the adventitia showed thickening with fibrosis. In addition, remarkable infiltration of inflammatory cells, including multinuclear giant cells phagocytosing fragmented elastic fibers, and destruction of elastic fibers were observed in the media. We diagnosed the cause of death as coronary insufficiency induced by coronary involvement due to Takayasu arteritis. Takayasu arteritis was not considered as a cause of sudden infant death, although this disease can affect the coronary artery. This report suggests that Takayasu arteritis can be a life-threatening condition even in infants.

The effects of low-dose methamphetamine pretreatment on endoplasmic reticulum stress and methamphetamine neurotoxicity in the rat midbrain.

Methamphetamine (METH) neurotoxicity is involved in METH-related deaths. It has been suggested that the midbrain, together with the striatum, is affected by METH neurotoxicity and the endoplasmic reticulum (ER) stress is induced in the processes of METH neurotoxicity. In this study, we examined the effects of low-dose METH administration for 5d on GRP78 and C/EBP homologous protein (CHOP), both of which are induced under ER stress, and METH neurotoxicity in the rat midbrain. We showed that 1mg/kg of METH induced an increase in GRP78 protein and mRNA expression 1d after the last injection, but had no effect on the levels of CHOP, tyrosine hydroxylase (TH), or GFAP. Secondly, we evaluated the induction of ER stress and the extent of METH neurotoxicity in the midbrain of animals pretreated with METH. In animals pretreated with saline, we observed elevated CHOP levels, together with decreased TH levels and increased GFAP levels, indicative of METH neurotoxicity, after neurotoxic METH administration, while there was no significant change in GRP78 levels. In contrast, low-dose METH (1.0mg/kg) pretreatment increased GRP78 levels and inhibited the induction of CHOP in the midbrain without METH neurotoxicity. These findings of ER stress in animals pretreated with METH were associated with an early increase in SOD1 levels and upregulation of Bcl-2. Therefore, our study suggests that pretreatment with low-dose METH may be protective against METH neurotoxicity in the midbrain, leading to the suppression of oxidative stress and apoptotic mechanisms, in part via ER stress-related pathways. Because chronic human METH abusers administrate low-dose METH repeatedly over an extended period before lethal injection, investigation of the pathophysiology of METH neurotoxicity in animals pretreated with low-dose METH might provide useful information on the pathophysiology of chronic and/or lethal METH use in cases of METH-related deaths.

RAGE mediates vascular injury and inflammation after global cerebral ischemia.

The receptor for advanced glycation end products (RAGE) is a multi-ligand receptor involved in a diverse range of pathological conditions. To analyze the roles of RAGE and its decoy receptor, endogenous secretory RAGE (esRAGE), in the global cerebral ischemia, three different mouse cohorts, wild-type, RAGE⁻/⁻, and esRAGE transgenic (Tg) mice were subjected to bilateral common carotid artery occlusion (BCCAO). RT-PCR and immunohistochemical analysis revealed that expression of RAGE was induced in the vascular cells at 12 h, and then in the neurons and glia from 3 to 7 days in the hippocampus after BCCAO. The numbers of surviving neurons in the hippocampal CA1 region were significantly higher in RAGE⁻/⁻ and esRAGE Tg mice than those in wild-type mice in the periods between 24 h and 7 days after BCCAO. Lower levels of 3-nitrotyrosine (3-NT) and higher levels of endothelial nitric oxide synthase (eNOS), together with enlarged vascular areas were observed in RAGE⁻/⁻ and esRAGE Tg mice at 12 h after BCCAO. In the later periods, expressions of glia-derived inflammatory mediators TNFα and inducible nitric oxide synthase (iNOS) were reduced in RAGE⁻/⁻ and esRAGE Tg mice. These results suggest that RAGE may contribute to delayed neuronal death after global cerebral ischemia by enhancing vascular injury and deleterious glia-mediated inflammation.

The effect of Ndrg2 expression on astroglial activation.

N-myc downstream-regulated gene 2 (Ndrg2) is a differentiation- and stress-associated molecule predominantly expressed in astrocytes in the central nervous system (CNS). To study the expression and possible role of Ndrg2 in quiescent and activated astrocytes, mice were administrated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropypridine (MPTP), a Parkinson disease (PD)-related neurotoxin which causes both neurodegeneration and glial activation. Immunohistological analysis revealed that Ndrg2 was highly expressed in both types of astrocytes, but less so in astrocytes during the early process of activation. Ndrg2 was also expressed in astrocyte-like cells, but not in neurons, in human brains from PD and Cortico-basal degeneration (CBD) patients. In cultured astrocytes, gene silencing of Ndrg2 significantly enhanced the numbers of 5-bromo-2'-deoxy-uridine (BrdU)-incorporated and proliferating cell nuclear antigen (PCNA)-positive cells, and reduced the length of cell processes and the amount of F-actin. In contrast, adenovirus-mediated overexpression of Ndrg2 significantly reduced the numbers of BrdU-incorporated and PCNA-positive cells, and enhanced the amount of F-actin. Fractionation and immunocytochemical analysis further revealed that Ndrg2 was located in different cellular fractions including the cytosol and cell surface membranes. These results suggest that Ndrg2 may regulate astroglial activation through the suppression of cell proliferation and stabilization of cell morphology.

Microglial and astrocytic changes in the striatum of methamphetamine abusers.

Little is known about the role of glial cells in the striatum of chronic methamphetamine (METH) users. In this study, we immunohistochemically examined glial reactions in the striatum of chronic METH users who did not abstain from METH use and died of drug intoxication. Human glucose transporter 5 (hGLUT), a useful marker of microglia, and CR3.43, a major histocompatibility complex class II antigen specific for reactive microglia, were immunostained. Glial fibrillary acidic protein (GFAP) and S100 Beta were used for astrocyte immunohistochemistry. We analyzed 12 chronic METH users and 13 control subjects, and detected a 200-240% increase in the number of hGLUT5-positive cells in chronic METH users (p<0.01). However, we did not detect any proliferation of CR3.43-positive cells. The number of GFAP-positive astrocytes increased, but this increase was not significant (p>0.05). Moreover, S100B-positive cell density between the two groups was not significant (p>0.05). This study demonstrates the absence of reactive gliosis in the striatum of chronic METH users who did not abstain for prolonged periods from METH use. The results suggest that chronic METH use by itself did not activate glial cells in humans and reactive gliosis may not be involved in the mechanism underlying the loss of control in drug intake, which is a characteristic feature of drug addiction.

Multiple hepatocellular carcinomas developed 15 months after commencement of chemotherapy for elderly acute myelogenous leukemia.

In May 2006, a 72-year-old man with acute myelogenous leukemia (M4Eo) was admitted to our hospital. He had been receiving antiandrogen treatment for prostate cancer (after an operation in 1998) and treatment for diabetes mellitus. He received chemotherapy according to the JALSG GML200 protocol, which led to complete remission; however, in January 2007, his leukemia recurred. CAG combination chemotherapy also resulted in complete remission by May 2007. In August 2007, he developed multiple liver tumors, abdominal pain, and fever. Contrast-enhanced computed tomography revealed hypovascular tumors in both early and delayed phases. Angiography showed ring-like tumor staining and a massive tumor, similar to those seen in metastatic hepatocellular carcinomas (HCCs). He eventually died because of aggressive enlargement of liver tumors during the following month accompanied by the simultaneous recurrence of leukemia and unsuccessful embolization of the hepatic artery. Autopsy specimens showed fibrosis and considerable iron deposition in the liver, suggested secondary hemochromatosis due to transfusion. We also detected multiple moderately differentiated primary HCCs. Secondary hemochromatosis, androgen imbalance, and humoral factors from leukemic cells were believed to be the causes of the rapid onset and development of HCCs.

Detection of diatom in formalin-fixed tissue by proteinase K digestion.

The diatoms detection has been proposed to be useful in the diagnosis of drowning. Enzymatic digestion of unfixed lung tissues and other organs with proteinase K is widely employed to detect diatoms. Handling unfixed organs or blood from the bodies with some infectious diseases could prove to be dangerous. In this study, we examined the application of enzymatic digestion for diatom detection to formalin-fixed lung obtained at autopsy. Furthermore, we assessed the effect of hydrogen peroxide on the contamination of the lung specimen with foreign bodies inhaled in the course of drowning, smoking, or air pollution. Formalin-fixed lung was heated in 0.01 M Tris-HCl buffer (pH 7.5) containing sodium dodecyl sulfate (SDS) (tissue lysis-buffer), with or without glycine. Thereafter, the lung was subjected to enzymatic digestion with proteinase K. A part of formalin-fixed or unfixed samples digested with proteinase K were incubated with hydrogen peroxide at 80 degrees C for 6 h or 12 h, while the residues were processed without incubation. Formalin-fixed samples heated in tissue lysis-buffer with glycine could be digested with proteinase K; further, the number and proportion of diatoms detected in both formalin-fixed and unfixed samples were observed to be similar. The results suggest that enzymatic detection of diatoms can be applied to formalin-fixed organs by heating the samples in glycine-containing tissue lysis-buffer. As the use of formalin-fixed tissue for diatom detection can decrease risk of contamination by pathogenic organisms during the course of enzymatic digestion, the method presented in this study would be beneficial, to some extent, to individuals performing diatom analysis. Moreover, our results suggest that archival organs stored in formalin solution could be available in diatom detection over a long time-period following autopsies. Clearer image of diatoms was observed in the specimen incubated with hydrogen peroxide for 6 h, in which inhaled foreign bodies were discolored, than those not subjected to incubation. Therefore, incubation of sample digested with hydrogen peroxide in the limited time would be helpful for quantitative and qualitative diatom analysis.

Detection of diatom in formalin-fixed organs by enzymatic digestion.

The detection of diatoms has been proposed to be useful in the diagnosis of drowning. Enzymatic digestion of unfixed lungs and other organs is widely used to detect diatoms. In the present study, we examined the application of enzymatic digestion for diatom detection in formalin-fixed organs obtained at autopsy. Furthermore, we assessed the effect of hydrogen peroxide on contamination of the lung specimen with foreign bodies inhaled in the course of drowning or as a result of smoking or air pollution. Unfixed lung was digested with proteinase K for 2d and centrifuged; the supernatant was then removed. On the other hand, formalin-fixed lung samples were boiled in Tris-HCl buffer containing sodium dodecyl sulfate (SDS) and then subjected to enzymatic digestion. A portion of formalin-fixed or unfixed samples digested with proteinase K was incubated with hydrogen peroxide at 80 degrees C and mounted on a slide, while the remaining portion was processed without incubation. Samples incubated with hydrogen peroxide showed clearer image of diatoms than those not incubated with hydrogen peroxide; this is because the inhaled foreign bodies were discolored in the former samples. Therefore, incubation of digested samples with hydrogen peroxide would be helpful for quantitative and qualitative analyses of diatoms.

[A case of peritonitis carcinomatosa from goblet cell carcinoid of the appendix treated by intraperitoneal paclitaxel and systemic S-1 chemotherapy].

Goblet cell carcinoid of the appendix is a rare neoplasm and clinically tends to take a malignant course. Most cases are young and early stage, and the surgical strategy is available. But appropriate chemotherapy for inoperable cases with peritoneal dissemination is not established. A 77-year-old woman with a past history of appendectomy was admitted to our hospital complaining of abdominal fullness. Abdominal computed tomography showed massive ascites and slight contrast enhancement of appendix. A tumor was found by colonoscopic examination at the orifice of vermiform and was diagnosed pathologically as goblet cell carcinoid of the appendix. Laparoscopy showed multiple peritoneal dissemination. We performed intraperitoneal paclitaxel(PTX)administration at 70 mg/m(2) week without any resection of the tumor. Ascites were reduced immediately, but drug-induced interstitial pneumonia occurred due to PTX. After steroid therapy, we switched to systemic S-1 therapy. For about one year, her tumor was controlled but became worse thirteen months after diagnosis and died. It is thought that intraabdominal paclitaxel administration and systemic S-1 therapy can be one of appropriate forms of chemotherapy for inoperable peritoneal carcinomatosis from goblet cell carcinoid of appendix.

[A long-surviving patient with lung pleomorphic carcinoma treated with postoperative carboplatin and paclitaxel combination chemotherapy].

We presented the case of a 46-year-old man with no medical or family history but with a history of smoking 3 packs of cigarettes per day for the past 25 years. He was admitted to our hospital due to hemoptysis. Chest computed tomography revealed a tumor of right upper lung and interstitial pneumonia in the surrounding lung parenchyma. He was operated upon and diagnosed with stage IIB pleomorphic carcinoma of the lung with invasion of the chest wall. He underwent three courses of postoperative carboplatin (CBDCA) (area under the curve 5 on day 1, every 3 weeks and paclitaxel(PTX) (200 mg/m(2); day 1, every 3 weeks) combination chemotherapy. No recurrence was observed for a period of 760 days after the operation. According to previous reports, lung pleomorphic carcinoma is aggressive and has a poor prognosis. Further, the significance of chemotherapy in the management of this disease has not been established. Postoperative combination chemotherapy of CBDCA and PTX may result in a good prognosis for this disease.

Long-term inhibition of intimal hyperplasia using vascular photodynamic therapy in balloon-injured carotid arteries.

Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg, was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength 664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit restenosis after vascular intervention.