Search PubMed⌕ Search

Biomedical subjects

B L Zhu

Publications and source records attributed to B L Zhu.

At least 19 recordsLinked to original sources

Praseodymium hydroxide and oxide nanorods and Au/Pr6O11 nanorod catalysts for CO oxidation.

Praseodymium hydroxide nanorods were synthesized by a two-step approach: First, metallic praseodymium was used to form praseodymium chloride, which reacted subsequently with KOH solution to produce praseodymium hydroxide. In the second step the hydroxide was treated with a concentrated alkaline solution at 180 degrees C for 45 h, yielding nanorods as shown by the scanning and transmission electron microscopy images. The results of X-ray diffraction and energy-dispersive X-ray spectroscopy experiments indicate that these nanorods are pure praseodymium hydroxide with a hexagonal structure, which can be converted into praseodymium oxide (Pr6O11) nanorods of a face-centered cubic structure after calcination at 600 degrees C for 2 h in air. Gold was loaded on the praseodymium oxide nanorods using HAuCl4 as the gold source, and NaBH4 was used to reduce the gold species to metallic nanoparticles with sizes of 8-12 nm on the nanorod surface. These Au/Pr6O11 nanorods exhibit superior catalytic activity for CO oxidation.

Journal Article↗

Effects of therapeutic agents on cellular respiration as an indication of metabolic activity.

Animal experiments are indispensable in the investigation of the toxicity of drugs on cells, but may not be preferred for ethical reasons and sensitivity. As an alternative procedure, we investigated the susceptibility of cells to drugs using the effect on cellular respiration as an indicator of cell activity (toxicity). The primary cultures (cell lines) used in this study included human fetal myocardial cells, skeletal muscle cells, nerve cells, hypophyseal cells, epithelial cells of gastric mucosa, lymphocytes, hepatocytes, pancreatic (exocrine) cells, renal tubular epithelial cells and fetal adrenal cortex cells, which were obtained from the American Type Culture Collection (ATCC). The drugs used were diazepam, haloperidol and levomepromazine maleate (psychoactive drugs), cisplatin and doxorubicin hydrochloride (anticancer agents). The cells were used at a density of 2 x 10(6) cells/2 mL of growth medium and, to test the susceptibility, each drug was prepared at a concentration of 10 g/mL. Experiment results indicated that, even with the same drug, sensitivity was markedly different depending on the cell lines. Cardiac muscle cells showed the strongest respiratory inhibition by Serenace and were least inhibited by Hirnamin. The highest sensitivity to Cercine was noted for neurons, while gastric mucosa cells had almost no sensitivity. Sensitivity to Serenace, which was expected to have a strong nerve action, was higher in myocardial cells instead. In the present study, we suggested the possibility of studying individual differences in drug sensitivity through investigation of toxicity in each organ as opposed to toxicity in the individual. In addition, Serenace, which was developed as a neurotopic agent, showed a higher toxicity in cardiac muscle cells than in neurons. This finding appeared noteworthy, not only for forensic toxicology, but also for clinical practice and drug development.

Cell Count↗

CeO2 nanorods and gold nanocrystals supported on CeO2 nanorods as catalyst.

The formation mechanism of uniform CeO2 structure at the nanometer scale via a wet-chemical reaction is of great interest in fundamental study as well as a variety of applications. In this work, large-scale well-crystallized CeO2 nanorods with uniform diameters in the range of 20-30 nm and lengths up to tens of micrometers are first synthesized through a hydrothermal synthetic route in 5 M KOH solution at 180 degrees C for 45 h without any templates and surfactants. The nanorod formation involves dehydration of CeO2 nanoparticles and orientation growth along the 110 direction in KOH solution. Subsequently, gold nanoparticles with crystallite sizes between 10 and 20 nm are loaded on the surface of CeO2 nanorods using HAuCl4 solution as the gold source and NaBH4 solution as a reducing agent. The synthesized Au/CeO2 nanorods demonstrate a higher catalytic activity in CO oxidation than the pure CeO2 nanorods.

Journal Article↗

DNA microarray: a high throughput approach for methylation detection.

We described a DNA microarray-based method combined with bisulphite treatment of DNA and regular PCR to examine hyper-methylation in promoter 1A of APC gene. A set of oligonucleotide probes were designed and immobilized on the aldehyde-coated glass slides for detecting the methylation pattern of 15 selected CpG sites in the region. The methylation status of 30 colorectal tumor samples have been examined by both of methylation-specific PCR (MS-PCR) and the present microarray method. The methylation pattern of the 15 CpG sites for the samples have been obtained with the microarray. A total of 19 samples out of 30 were methylated by microarray, in which five samples cannot be detected by MS-PCR due to the methylated CpG patterns not accordant to the MS-PCR primers. The detecting ratio for methylation of APC gene of colorectal tumor samples increased from 46.7% with MS-PCR to 63.3% with the microarray, which successfully demonstrated that DNA microarray-based method not only can obtained the methylation patterns for the related genes, but also decrease the false-negative results of methylation status by the conventional MS-PCR for the investigated genes.

Adenomatous Polyposis Coli Protein↗

Sudden death of an infant with 'an early epileptic encephalopathy'.

This article reports an autopsy case of sudden death of an infant with an infrequent encephalopathy involving epileptic episodes. The infant was a 1-year and 10-month-old boy, who had a history of the first convulsive seizures in the third month after birth. The clinical diagnosis was described as 'an early infantile epileptic encephalopathy with suppression-bursts' (Ohtahara syndrome). On a winter day, he was collapsed following a high fever and was already dead on the arrival at a hospital. The body was small for the age and poorly nourished. The autopsy and postmortem magnetic resonance imaging scan (MRI) of formalin-fixed brain revealed advanced unsymmetric brain atrophy with cortical dysplasia, which were prominent in the left temporal and right occipital lobes, and sclerotic atrophy of the parahippocampal gyri, additionally showing a feature of the olivo-ponto-cerebellar atrophy. However, the cause of death was pathologically and microbiologically determined as bacterial bronchopneumonia following pulmonary infection of the influenza A virus. In sudden death cases of physically handicapped infants, the investigation of viral infection in consideration of an epidemiological survey is important even when the death can be pathomorphologically explained.

Brain↗

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fatal poisoning.

To evaluate the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in fatal poisoning in relation to the effects of drugs and poisons on respiratory function, 42 forensic autopsy cases were examined by scoring the staining intensity. The highest scores of SP-A staining, with dense granular deposits (aggregates) in the intra-alveolar space, were observed in fatalities from pancuronium bromide (muscle relaxant) injection and petroleum (butane) gas inhalation. Poisoning with organophosphate pesticides and arsenic (ingestion) showed a second grade SP-A score. However, The SP-A scores were relatively low in ethanol and sedative-hypnotic intoxication. Carbon monoxide intoxication showed a varied degree of SP-A score, and the aggregated SP-A score tended to be higher in cases of lower blood carboxyhemoglobin concentration. A varied SP-A score was also observed in methamphetamine fatalities, in which the score was relatively low in cases with a higher serum drug level. Increase of SP-A was not always associated with the intra-alveolar effusion or hemorrhages. The above-described observations suggested that the immunohistochemical score of SP-A may be a possible indication for intensity and duration of drug/poison-dependent respiratory distress.

Adolescent↗

Fatal traumatic rupture of an aortic aneurysm of the sinus of Valsalva: an autopsy case.

This report describes an autopsy case of a rare type of aortic sinus of Valsalva aneurysm, which caused fatal rupture from a blunt chest impact. A 51-year-old male was hit in the chest with a fist, lost consciousness after about 15min and died after approximately 7h. The postmortem examination revealed a large saccular aneurysm of the right coronary sinus bulging on the right atrium, which had a full laceration causing pericardial hematoma (cardiac tamponade). A related chest wall injury was observed in the right outer mammary region. A rare type of bulging onto the right atrium and subsequent sclerosis of the right coronary artery appeared to have greatly contributed to the fatal rupture.

Aortic Rupture↗

Post-mortem urinary myoglobin levels with reference to the causes of death.

To evaluate pathophysiological significance of post-mortem urinary myoglobin levels in determining the cause of death, we investigated 210 forensic autopsy cases, partially in comparison with serum levels. Post-mortem serum myoglobin levels were extraordinary high in most cases possibly due to post-mortem change. Urinary myoglobin levels did not correlate with the serum levels, showing possible post-mortem elevation in cases of a prolonged post-mortem period over 48h. A high (>1000 ng/ml), moderate (100-1000 ng/ml), slight (50-100 ng/ml) and not significant (<50 ng/ml) elevation of urinary myoglobin were observed in 26, 43, 31 and 110 cases, respectively. Half the highly elevated cases were those with a survival time over 24h. In cases of minor muscle injury such as head trauma, elevation of urinary myoglobin level was closely related to longer survival. In acute/subacute deaths with a post-mortem interval within 48h, a significant difference was observed in relation to the blood carboxyhemoglobin (COHb) levels of fire victims: myoglobinuria over 100 ng/ml was more frequently and markedly observed in cases with COHb below 60% than over 60%, suggesting muscle damage in fatal burns. Similar elevation was observed in heat stroke victims, and also in some cases of acute and subacute death from polytrauma, asphyxiation, drowning, electricity and spontaneous cerebral bleeding, but not in myocardial infarction. Thus, it was suggested that high post-mortem urinary myoglobin levels in acute and subacute death cases may be a possible indicator of antemortem massive skeletal muscle damage as well as exertional muscle hyperactivity or convulsive disorders associated with hypoxia.

Adolescent↗

Intranuclear ubiquitin immunoreactivity in the pigmented neurons of the substantia nigra in fire fatalities.

To evaluate the significance of immunohistochemical staining of ubiquitin (heat shock protein) in the midbrain for medico-legal investigation of death in fires, we examined forensic autopsy cases of fire fatalities (n = 35) in comparison with controls (n = 27; brain stem injury, acute myocardial infarction and carbon monoxide poisoning other than fire fatality). There were two intranuclear staining patterns in the nuclei of pigmented substantia nigra neurons: a type of inclusion (possible Marinesco bodies) and a diffuse staining. Percentage of nuclear ubiquitin positivity (Ub-positive %) in fire fatalities (2.7-44.7%; mean, 18.5%) was significantly higher than in brain stem injury (n = 9; 0-10.4%; mean, 4.5%) and myocardial infarction (n = 14; 1.5-14.6%; mean, 6.9%), independently of blood carboxyhemoglobin (COHb) levels. Age-dependent increase in Ub-positive % was observed in lower COHb (< 60%) cases. The intranuclear diffuse ubiquitin staining was not observed in cases of high blood cyanide level (> 1.0 microg/ml). These observations showed that intranuclear ubiquitin immunoreactivity of the pigmented substantia nigra neurons in the midbrain was induced by severe stress in fires.

Aged↗

Intranuclear ubiquitin immunoreactivity of the pigmented neurons of the substantia nigra in fatal acute mechanical asphyxiation and drowning.

To evaluate the significance of immunohistochemical staining of ubiquitin (heat shock protein) in the midbrain for the medico-legal diagnosis of fatal asphyxiation and drowning, we investigated forensic autopsy cases of fatal mechanical asphyxia (n = 18), manual/ligature strangulation (n = 9), hanging (n = 4), aspiration/choking (n = 5) and drowning (n = 16). These were compared to control groups (n = 30) consisting of fatalities from brainstem injury (n = 12) and acute myocardial infarction (n = 18). Ubiquitin was clearly demonstrated in the nuclei of pigmented substantia nigra neurons, showing two intranuclear staining patterns: a type of inclusion (possibly Marinesco bodies) and a diffuse staining. The diffuse staining was significantly more frequently observed in cases of drowning. The percentage of total ubiquitin positive neurons was frequently higher in strangulation (5.1-28.4%, mean 17.0%), aspiration/choking (5.3-32.0%, mean 17.6%) and drowning (7.0-34.1%, mean 19.8%), but relatively low in hanging (5.1-12.7%, mean 8.6%), brainstem injury (0-10.4%, mean 5.0%) and acute myocardial infarction (1.5-16.9%, mean 8.3%). These observations suggest that intranuclear ubiquitin immunoreactivity of the pigmented substantia nigra neurons in the midbrain was induced by a fatal severe stress on the central nervous system in asphyxiation and drowning.

Adult↗

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fire victims.

To evaluate the forensic pathological significance of the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in determining the cause of death in fires, 57 fire victims were examined by scoring the staining intensity. The highest SP-A score with dense granular deposits (aggregates) in the intra-alveolar space was frequently observed in cases with a lower blood carboxyhemoglobin (COHb) level (<60%). The SP-A score was relatively low in carbon monoxide intoxication due to causes other than fires. High SP-A scores showed a relation to the serum level and in part related to the bloody exudate in the lower airway. These observations suggested that the increase in SP-A in fire victims may be mainly related to pulmonary alveolar injury due to the inhalation of hot air and/or irritant gases rather than hypoxia.

Journal Article↗

Immunohistochemistry of pulmonary surfactant-associated protein A in acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a fatal complication in severe traumas and diseases. Although the contribution of pulmonary surfactant abnormality to the pathogenesis of ARDS has been clinically fairly well investigated, the histopathological evidence has not been established. The aim of this study was to clarify the immunohistochemical distribution of surfactant-associated protein A (SP-A) for early diagnosis of ARDS with special regard to hyaline membrane (HM) formation. Two-hundred-and-ten autopsy cases of prolonged death from various traumas and diseases were investigated. ARDS were observed in 23 cases, showing speckled SP-A immunostaining. During the early, exudative phase of ARDS, characteristic SP-A distribution showed intense staining in the intra-alveolar massive aggregates and thick 'peeling'-like substances accompanied with a lot of granular staining. During the proliferative phase, localized accumulation of granular SP-A and macrophages containing dense granular SP-A became predominant. During the final fibrotic phase, SP-A staining in HMs became weak, and disseminated granular staining was observed in the alveolar spaces. These findings provide morphological evidence of the increase of SP-A during the early phase of ARDS, including some molecular alteration and its decrease during the late phase. Characteristic SP-A distribution in the exudative phase appeared to be especially useful for early histopathological diagnosis of respiratory distress, even prior to the appearance of typical HMs.

Journal Article↗

[Radiographic examination of skeletalized remains of an abandoned infant: a case report with special reference to odontological findings].

A homeless couple confessed that they had buried their baby, who died at the age of three months, in the graveyard two years earlier. The recovered infantile remains had been already completely skeletonized and dismembered. However, the maxilla and mandibula of the average matured infants, the age of the body was estimated to be 1 to 2.5 months old on the basis of the degree of calcification of deciduous teeth.

Age Determination by Teeth↗

Child and elderly victims in forensic autopsy during a recent 5 year period in the southern half of Osaka city and surrounding areas.

To outline the recent features of child and elderly victims from the medico-legal perspective with special reference to abuse and neglect, a retrospective investigation of forensic autopsy cases over a 5 year period (1994-1998) in the southern half of Osaka city and surrounding areas (a population of 1.57 million) was undertaken. Among 646 autopsy cases, there were 53 child cases (under the age of 15 years, about 80% below 6) and 121 elderly cases (65 years old and above). Nearly half of the child deaths and more than half of the elderly deaths were described as accidental. Fire and traffic victims were much more frequent in the elderly. Child victims included those of neonaticide/infanticide (n=6), physical abuse (n=10), unintentional fatal infliction (n=2), neglect (n=2), mutual suicide (n=2), suicide (n=1) and murder (n=3). Child abuse and neglect were domestic maltreatment by the parents. In this series, there was a comparable number of fatalities due to maltreatment in the elderly (n=13) and in children, and non-domestic violence was more frequent in the elderly than domestic violence. Elderly females tended to be battered by their sons or grandsons in domestic violence cases, whereas males were predominantly attacked by younger males in non-domestic violence. The other elderly victims included those of self-neglect (n=2), murder (n=7) and suicide (n=9). Non-domestic homicide of the elderly occurred mainly in the center of the city, whereas domestic maltreatment of children and the elderly was sporadic, although somewhat more frequent in the peripheral zone of the city and the surrounding areas. The above profile of child and elderly abuse suggests a substantial influence of social and familial backgrounds.

Accidents↗

Automated determination of carboxyhemoglobin contents in autopsy materials using head-space gas chromatography/mass spectrometry.

To establish a method for the routine analysis of carboxyhemoglobin (COHb) in autopsy materials including those which have undergone postmortem changes, e.g. thermo-coagulation, putrifaction and contamination, an automated head-space gas chromatography/mass spectrometry (GC/MS) analysis was utilized. The procedure consisted of preparation of the sample in a vial and a carbon monoxide (CO) saturated sample, for estimation of hemoglobin content, in another vial, the addition of n-octanol, potassium ferricyanide and an internal standard (t-butanol), GC separation and determination of CO using a GC/MS system equipped with an automated head-space gas sampler. The method was practical not only with the blood and bone marrow aspirates to confirm the findings on the CO-oximeter system, but also with the thermo-coagulated and putrified blood.

Automation↗

Novel approach to quantitative reverse transcription PCR assay of mRNA component in autopsy material using the TaqMan fluorogenic detection system: dynamics of pulmonary surfactant apoprotein A.

A novel approach to quantitative reverse transcription (RT)-PCR assay of mRNA component using fluorescent TaqMan methodology and a new instrument (ABI Prism 7700 sequence detection system) was developed for autopsy materials. Pulmonary surfactant apoprotein A (SP-A) mRNA from a cadaveric lung was quantitated in real-time. The target SP-A gene and the endogenous reference of glyceraldehyde-3-phosphate (GAPDH) were amplified in the same tube, and an amount of the target was normalized to the reference. This assay had a high reproducibility and discrimination even in forensic autopsy materials up to 96 h postmortem. Elevated SP-A expressions were determined in some cases. This system without post-PCR sample handling would be a very useful tool in pathological diagnosis and DNA analysis.

Adolescent↗

Immunohistochemical distribution of C-reactive protein in the hepatic tissue in forensic autopsy.

Previously, we examined the expression of C-reactive protein (CRP) in hepatic tissues in fatal injuries (injury deaths) immunohistochemically, and classified the CRP distribution into three patterns: diffuse (D-) pattern, diffuse with strong positivity in the hepatic lobules; periportal (PP-) pattern, characterized by positive cells in the periportal region of some lobules; focal (F-) pattern, showing small islands of positive cells in some lobules. There was a relationship between the CRP distribution and the survival time. In this study, we further analyzed the deaths including those due to other than fatal injuries (non-injury deaths), and a study of a total of 314 deaths from various causes was performed. Generally, non-injury deaths showed findings similar to those in injury deaths. PP- and/or F-patterns were observed in 43.7% of cases having a short survival time (<6 h), but found in only 3% of those surviving longer (>6 h), showing that such findings are suggestive of a short survival time. D-pattern was found more frequently in non-acute deaths (60.4%), than in acute deaths (10.9%). In acute deaths, D-pattern was found in some cases showing extensive tissue injuries, such as burns and polytrauma, and inflammative predisposition. Immunohistochemical findings also showed some correlation with the serum CRP level. Our data suggest that hepatic CRP immunohistochemistry may be a useful tool for elucidating the dying process.

Acute Disease↗

Immunohistochemistry of pulmonary surfactant apoprotein A in forensic autopsy: reassessment in relation to the causes of death.

To reassess the immunohistochemical distribution of pulmonary surfactant apoprotein A (SP-A) in relation to the causes of death, 282 forensic autopsy cases were reviewed. The most intense and dense granular immunostaining of intra-alveolar SP-A was observed in the hyaline membrane syndrome from various traumas, protracted death from drowning, and perinatal aspiration of amniotic fluid. Similar granular staining pattern was found in fatal poisoning by a muscle relaxant and organophosphate pesticides. An evident increase of intra-alveolar granular staining was noted in most fatalities from mechanical asphyxia and drowning, and some cases of fire death. SP-A staining was usually very weak or sparse in alcohol intoxication, poisoning by hypnotics and also carbon monoxide poisoning. These findings suggest that the amount of intra-alveolar granular SP-A staining may be a possible indicator of severity and duration of respiratory distress (agony) from peripheral (non-central nervous system) origin and alveolar damage.

Asphyxia↗