169 research outputs found
Necessity to Measure PCBs and Organochlorine Pesticide Concentrations in Human Umbilical Cords for Fetal Exposure Assessment
Three types of tissue samples—umbilical cord (UC), umbilical cord serum (CS), and maternal serum (MS)—have often been used to assess fetal exposure to chemicals. In order to know the relationship of contamination between mothers and fetuses, we measured persistent chemicals in comparable sets of the three tissue samples. Also, we analyzed the association between the chemicals in maternal and fetal tissues to know which tissue is the best sample for fetal exposure assessment. On a wet basis, the chemical concentrations were of the order MS > CS > UC, except for some chemicals such as cis-chlordane and endosulfan. On a lipid basis, the concentrations in UC were nearly equal or often higher than in MS, but the concentrations in CS were usually lower than in others. Hexachlorocyclohexanes and penta-, hexa-, and heptachlorinated biphenyls showed an association between the concentrations in UC versus MS, and UC versus CS. These chemicals also showed high correlation coefficients between the chemical concentrations in UC of first babies and maternal age. These chemicals were closely related to each other when grouped on the basis of their concentrations using cluster analysis. In conclusion, we insist that UC is the best sample to assess fetal contamination status of persistent chemicals. There is a possibility that the assessment based on the contamination levels in CS result in an underestimation
Rational and practical exfoliation of graphite using well-defined poly(3-hexylthiophene) for the preparation of conductive polymer/graphene composite
Spermatogenic cell-specific type 1 hexokinase is the predominant hexokinase in sperm
Hexokinase is the first enzyme in the glycolytic pathway and utilizes ATP to convert glucose to glucose-6-phosphate (G6P). We previously identified three variant transcripts of Hk1 that are expressed specifically in spermatogenic cells, have different 5′ untranslated regions, and encode a protein (HK1S, spermatogenic cell-specific type 1 hexokinase) in which the porin-binding domain (PBD) of HK1 is replaced by a novel N-terminal spermatogenic cell-specific region (SSR). However, the level of expression of the individual variant transcripts or of the other members of the hexokinase gene family (Hk2, Hk3, and Gck) in spermatogenic cells remains uncertain. We show that Hk1, Hk2, and Hk3 transcripts levels are quite low in spermatocytes and spermatids and Gck transcripts are relatively abundant in spermatids, but that GCK is not detected in spermatozoa. Using real time RT-PCR (qPCR) with primers specific for each of the three variant forms and RNA from whole testis and isolated germ cells, we found that transcripts for Hk1_v2 and Hk1_v3, but not for Hk1_v1, are relatively high in spermatids. Similar results were seen using spermatogenic cells isolated by laser-capture microdissection (LCM). Immunoblotting studies found that HK1S is abundant in sperm, and immunostaining confirmed that HK1S is located mainly in the principal piece of the sperm flagellum, where other spermatogenic cell-specific glycolytic enzymes have been found. These results strongly suggest that HK1, HK2, HK3 and GCK are unlikely to have a role in glycolysis in sperm and that HK1S encoded by Hk1_v2 and Hk1_v3 serves this role
Rhophilin, a small GTPase Rho-binding protein, is abundantly expressed in the mouse testis and localized in the principal piece of the sperm tail
AbstractTissue distribution and cellular localization of rhophilin, a 71 kDa Rho-binding protein, were examined in mice. Rhophilin mRNA was highly expressed in adult testis, but was absent in the testis of W/WV mice deficient in germ cells. An anti-rhophilin antibody detected a band of an expected size in sperm extracts, which was enriched in the tail fraction. Immunofluorescence analysis revealed two lines of striated staining running in parallel in the principal piece of the sperm tail. These results suggest that rhophilin is expressed in germ cells and localized in the fibrous sheath of the sperm tail
Cleavage of Disulfide Bonds in Mouse Spermatogenic Cell-Specific Type 1 Hexokinase Isozyme Is Associated with Increased Hexokinase Activity and Initiation of Sperm Motility1
During epididymal transit, sperm acquire the ability to initiate rapid forward progressive motility on release into the female reproductive tract or physiological media. Glycolysis is the primary source of the ATP necessary for this motility in the mouse, and several novel glycolytic enzymes have been identified that are localized to the principal piece region of the flagellum. One of these is the spermatogenic cell-specific type 1 hexokinase isozyme (HK1S), the only member of the hexokinase enzyme family detected in sperm. Hexokinase activity was found to be lower in immotile sperm immediately after removal from the cauda epididymis (quiescent) than in sperm incubated in physiological medium for 5 min and showing rapid forward progressive motility (activated). However, incubating sperm in medium containing diamide, an inhibitor of disulfide bond reduction, resulted in lower motility and HK activity than in controls. HK1S was present in dimer and monomer forms in extracts of quiescent sperm but mainly as a monomer in motile sperm. A dimer-size band detected in quiescent sperm with phosphotyrosine antibody was not detected in activated sperm, and the monomer-size band was enhanced. In addition, the general protein oxido-reductase thioredoxin-1 was able to catalyze the in vitro conversion of HK1S dimers to the monomeric form. These results strongly suggest that cleavage of disulfide bonds in HK1S dimers contributes to the increases in HK activity and motility that occur when mouse sperm become activated
The effects of chemotherapy-induced alopecic experience on daily living
がん化学療法に伴う脱毛体験が患者の日常生活にもたらす影響について明らかにすることを目的に,15名の患者に対して自由回答法による半構造化面接を実施した.同意を得て録音した面接内容の逐語録をデータとして,Krippendorff. Kの内容分析の手法を用いて分析を行った.分析の結果,がん化学療法に伴う脱毛体験が患者の日常生活にもたらす影響として,【脱毛した自分に違和感を感じながら人目を気にして生活する】【脱毛に備えて事前に準備する】【脱毛は仕方がないと捉え治療を受けることを優先させる】【予想以上の急速大量脱毛にがんであることの事実を突きつけられる】【時間をかけて脱毛の事実を受け入れ違う捉え方を見出す努力をする】【他者と距離を取りながら生活する】【立場,性差による脱毛の捉え方の違いを実感する】【脱毛した毛髪の処理を気にかけながら生活する】【脱毛のつらい経験から検診の啓蒙活動を行う】の9つが明らかとなった.脱毛に対して事前に十分な準備が行え,自分なりの対処法についてイメージできるよう具体的な情報提供を行うとともに,性差,治療効果や患者の治療への思いなどによって脱毛に対する捉え方はさまざまであることから,看護師はその人自身の脱毛の受け止め方や,脱毛が及ぼす生活への支障について把握し,必要な情報を提供することや患者の思いが表出しやすい環境を整えることが大切である.The present study aimed to clarify the effects of chemotherapy-induced alopecia on the daily lives of cancer patients. Semi-structured interviews comprising free-answer questions based on an interview guide were conducted on 15 cancer patients experiencing chemotherapy-induced alopecia. Analysis revealed the following 9 effects of chemotherapy-induced alopecia on patients’ daily lives : ‘self-consciousness accompanied by feeling strange about oneself due to hair loss’, ‘preparing for hair loss in advance’, ‘prioritizing treatment and perceiving hair loss as inevitable’, ‘come to terms with chemotherapy-induced alopecia gradually, make an effort to find out a different kind of ways for it’, ‘being hit by the reality of cancer due to greater than anticipated rapid loss of large quantities of hair’, ‘intentionally living daily life at a distance from others’, ‘recognizing the situation and the gender-based differences in perception of hair loss’, ‘worrying about disposing of the lost hair’, ‘becoming more informed about medical examinations due to the hard experience of hair loss’. The present findings indicated that chemotherapy-induced alopecia is perceived in various ways depending on gender, treatment effectiveness and patients’ feelings towards treatment. It is important for nurses to understand patients’ individual acceptance of alopecia and related difficulties in daily life while creating an environment that allows patients to express their feelings. Nurses should also provide specific information enabling patients to visualize personal coping techniques and sufficiently prepare for alopecia
Abdominal subcutaneous adipose tissue accumulation is positively correlated with hepatic steatosis in Sprague-Dawley rats
The precise roles of visceral (VAT) or subcutaneous adipose tissue (SAT) on hepatic fat accumulation have not been fully elucidated. In this report, we examined the correlation between VAT or SAT volume and severity of hepatic fat accumulation. In the present study, Sprague-Dawley (SD) rats were fed a standard diet containing 10% fat or a high-fat diet containing 45% or 60% fat for 16 weeks. Abdominal VAT and SAT volume, as well as fat percentage of the liver were measured by computed tomography (CT). Hepatic triglyceride (TG) content and histopathological findings of hepatic steatosis were also examined. Abdominal SAT weight/body weight ratio was positively and strongly correlated with abdominal VAT weight/body weight ratio. Fat percentage of the liver by CT evaluation, hepatic TG content, and hepatic steatosis score by histopathological evaluation showed positive correlations with one another. Fat percentage of the liver by CT evaluation and hepatic TG content was positively correlated with both the abdominal VAT weight/body weight ratio and SAT weight/body weight ratio, respectively. Furthermore, hepatic TG content was negatively correlated with the abdominal VAT weight/SAT weight ratio. Our data suggest that abdominal SAT accumulation is positively correlated with hepatic steatosis in SD rats, rather than abdominal VAT accumulation. Further investigations are needed in order to clarify the precise mechanisms of SAT and VAT effects on the development of hepatic fat accumulation
Chiba University\u27s approach to international-standard education : A report of study tour to International Organizations in Geneva
[要旨] 千葉大学予防医学センターでは,グローバルな視点や課題解決能力を持った学生を育成するための取組みのひとつとして,2013年度よりWHO本部等と連携した「国際機関視察研修」を実施している。千葉大学は2016年4月より三大学(千葉大学・金沢大学・長崎大学)共同大学院として先進予防医学共同専攻を開講したが,2016年9月に実施した第4回目となる同研修には,三大学の一つである金沢大学からも教員・学生が参加し,WHOをはじめとする国際機関の視察や職員からの講義を受ける等,社会医学に関する国際機関の取組み等について幅広く理解を深めた。[Summary] In April 2016, Center for Preventive Medical Sciences(CPMS), Chiba University launched the Division of Advanced Preventive Medical Sciences in cooperation with Kanazawa University and Nagasaki University in order to nurture research in and further clinical practice of“personalized preventive medicine”with the aim of developing understanding of the impact of biological characteristics and environmental factors to individuals and so that disease can be prevented even before a prodrome appears. As one sphere of its activities, Chiba University and Kanazawa University jointly provided the special training program in cooperation with international organizations such as the WHO, IOM and IFRC, and the Permanent Mission of Japan to the International Organizations in Geneva for three days in September 2016. A total of 40 clinicians, researchers, students and administrative staff from both universities participated in the program and studied through lectures and discussion a range of current global issues relating to public health
Polychlorinated biphenyl levels in the blood of Japanese individuals ranging from infants to over 80 years of age
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