Takahiro Umehara

Bio: Takahiro Umehara is an academic researcher from Nagasaki University. The author has contributed to research in topics: Hypothermia & microRNA. The author has an hindex of 9, co-authored 22 publications receiving 242 citations. Previous affiliations of Takahiro Umehara include Kyushu University.

Pattern of poisoning in Japan: selection of drugs and poisons for systematic toxicological analysis

Abstract: Patterns of poisoning are known to be different in different countries, because of the local environmental, cultural, and religious situations. Therefore, in Japan, it is important to know the pattern of poisoning in our own country and to prepare for every poisoning case by establishing an efficient systematic toxicological analysis system in forensic practice. We conducted a retrospective study of the kinds of compounds causing poisonings and the frequency of their use based on two series of reports dealing with poisoning cases in Japan prepared by the National Research Institute of Police Science and the Japanese Society of Legal Medicine for 2003 to 2006. From these reports, 459 and 177 compounds, respectively, were extracted as poisonous compounds over the study period. After data analysis, we selected 314 drugs and poisons as important target compounds for systematic drug analysis in Japan; they included 36 volatile compounds, 14 abused drugs, 170 medical drugs, 60 pesticides, 13 natural toxins, and 21 others. This is the first study to show the toxic drugs and poisons to be analyzed in Japan based on frequency of use, and as such the list will be useful in establishing the most efficient screening system in forensic practice.

Identification of Specific miRNAs in Neutrophils of Type 2 Diabetic Mice: Overexpression of miRNA-129-2-3p Accelerates Diabetic Wound Healing.

Abstract: Neutrophils are involved in the first stage of acute inflammation. After injury, they are mobilized and recruited to the injured tissue. In diabetes, wound healing is delayed and aberrant, leading to excessive recruitment and retention of neutrophils that fail to promote angiogenesis and prolong inflammation. However, the exact pathological mechanisms of diabetic-derived neutrophils in chronic inflammation remain unclear. Here, miRNA profiling of neutrophils from bone marrow in type 2 diabetic mice was performed using a microarray. miRNAs regulate the posttranscriptional expression of target mRNAs and are important in countering inflammation-related diseases. Our study revealed that miRNAs exhibit differential expression in diabetic-derived neutrophils compared with non-diabetic-derived neutrophils, especially miR-129 family members. miR-129-2-3p directly regulated the translation of Casp6 and Ccr2, which are involved in inflammatory responses and apoptosis. Furthermore, miR-129-2-3p overexpression at the wound site of type 2 diabetic mice accelerated wound healing. These results suggest possible involvement of miR-129-2-3p in diabetic-derived neutrophil dysfunction and that retention kinetics of neutrophils and chronic inflammation may be initiated through miR-129-2-3p-regulated genes. This study characterizes changes in global miRNA expression in diabetic-derived neutrophils and systematically identifies critical target genes involved in certain biological processes related to the pathology of diabetic wound healing.

Autopsy report for a caffeine intoxication case and review of the current literature

Abstract: Caffeine (1,3,7-trimethylxanthine) is a popular mild central nervous system stimulant found in the leaves, seeds and fruits of various plants and in foodstuffs such as coffee, tea, and chocolate, among others. Caffeine is widely used and is not associated with severe side effects when consumed at relatively low doses. Although rarely observed, overdoses can occur. However, only a few fatal caffeine intoxication cases have been reported in the literature. Herein, we report the pathological examination results and information on caffeine concentrations in the blood, urine and main organs in a fatal caffeine intoxication case. Even though high caffeine concentrations were found in the systemic organs, no caffeine-related pathological changes were detected.

Targeting miR‐223 in neutrophils enhances the clearance of Staphylococcus aureus in infected wounds

Abstract: Argonaute 2 bound mature microRNA (Ago2‐miRNA) complexes are key regulators of the wound inflammatory response and function in the translational processing of target mRNAs. In this study, we identified four wound inflammation‐related Ago2‐miRNAs ( miR‐139‐5p , miR‐142‐3p , miR‐142‐5p , and miR‐223 ) and show that miR‐223 is critical for infection control. miR‐223 Y /− mice exhibited delayed sterile healing with prolonged neutrophil activation and interleukin‐6 expression, and markedly improved repair of Staphylococcus aureus ‐infected wounds. We also showed that the expression of miR‐223 was regulated by CCAAT/enhancer binding protein alpha in human neutrophils after exposure to S. aureus peptides. Treatment with miR‐223 Y /− ‐derived neutrophils, or miR‐223 antisense oligodeoxynucleotides in S. aureus ‐infected wild‐type wounds markedly improved the healing of these otherwise chronic, slow healing wounds. This study reveals how miR‐223 regulates the bactericidal capacity of neutrophils at wound sites and indicates that targeting miR‐223 might be of therapeutic benefit for infected wounds in the clinic.

Sudden infant death syndrome

Abstract: The term: SID syndrome applies to sudden and unexpected death of the infant for which no diagnostic fetal factor has been found. It is also applied to sudden death of a less than one year old baby, the cause is not recognizable after complete post mortem study, and review of disease records. Such a death will be a very bitter and sorrowful experience for the family, therefor the nurses are bound to support the family both mentally and spiritually.

Pasteurella multocida: from Zoonosis to Cellular Microbiology

Abstract: In a world where most emerging and reemerging infectious diseases are zoonotic in nature and our contacts with both domestic and wild animals abound, there is growing awareness of the potential for human acquisition of animal diseases. Like other Pasteurellaceae, Pasteurella species are highly prevalent among animal populations, where they are often found as part of the normal microbiota of the oral, nasopharyngeal, and upper respiratory tracts. Many Pasteurella species are opportunistic pathogens that can cause endemic disease and are associated increasingly with epizootic outbreaks. Zoonotic transmission to humans usually occurs through animal bites or contact with nasal secretions, with P. multocida being the most prevalent isolate observed in human infections. Here we review recent comparative genomics and molecular pathogenesis studies that have advanced our understanding of the multiple virulence mechanisms employed by Pasteurella species to establish acute and chronic infections. We also summarize efforts being explored to enhance our ability to rapidly and accurately identify and distinguish among clinical isolates and to control pasteurellosis by improved development of new vaccines and treatment regimens.

Immunology of Acute and Chronic Wound Healing

Abstract: Skin wounds greatly affect the global healthcare system, creating a substantial burden on the economy and society. Moreover, the situation is exacerbated by low healing rates, which in fact are overestimated in reports. Cutaneous wounds are generally classified into acute and chronic. The immune response plays an important role during acute wound healing. The activation of immune cells and factors initiate the inflammatory process, facilitate wound cleansing and promote subsequent tissue healing. However, dysregulation of the immune system during the wound healing process leads to persistent inflammation and delayed healing, which ultimately result in chronic wounds. The microenvironment of a chronic wound is characterized by high quantities of pro-inflammatory macrophages, overexpression of inflammatory mediators such as TNF-α and IL-1β, increased activity of matrix metalloproteinases and abundance of reactive oxygen species. Moreover, chronic wounds are frequently complicated by bacterial biofilms, which perpetuate the inflammatory phase. Continuous inflammation and microbial biofilms make it very difficult for the chronic wounds to heal. In this review, we discuss the role of innate and adaptive immunity in the pathogenesis of acute and chronic wounds. Furthermore, we review the latest immunomodulatory therapeutic strategies, including modifying macrophage phenotype, regulating miRNA expression and targeting pro- and anti-inflammatory factors to improve wound healing.