bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Response to Acidic pH Through OGR1 in a Human Osteoblastic Cell Line
Authors: Tomura Hideaki , Wang Ju-Qiang , Liu Jin-Peng , Komachi Mayumi , Damirin Alatangaole , Mogi Chihiro , Tobo Masayuki , Nochi Hiromi , Tamoto Koichi , Im Doon-Soon , Sato Koichi , Okajima Fumikazu
Published: February 2008

Acidosis has been shown to induce depletion of bone calcium from the body. This calcium release process is thought to be partially cell mediated. In an organ culture of bone, acidic pH has been shown to induce cyclooxygenase-2 (COX-2) induction and prostaglandin E2 (PGE2) production, resulting in stimulation of bone calcium release. However, the molecular mechanisms whereby osteoblasts sense acidic circumstances and thereby induce COX-2 induction and PGE2 production remain unknown. In this study, we used a human osteoblastic cell line (NHOst) to characterize cellular activities, including inositol phosphate production, intracellular Ca2+ concentration ([Ca2+]i), PGE2 production, and COX-2 mRNA and protein expression, in response to extracellular acidification. Small interfering RNA (siRNA) specific to the OGR1 receptor and specific inhibitors for intracellular signaling pathways were used to characterize acidification-induced cellular activities. We found that extracellular acidic pH induced a transient increase in [Ca2+]i and inositol phosphate production in the cells. Acidification also induced COX-2 induction, resulting in PGE2 production. These proton-induced actions were markedly inhibited by siRNA targeted for the OGR1 receptor and the inhibitors for Gq/11 protein, phospholipase C, and protein kinase C. We conclude that the OGR1/Gq/11/phospholipase C/protein kinase C pathway regulates osteoblastic COX-2 induction and subsequent PGE2 production in response to acidic circumstances.
NSM and cognitive-functional models of grammar
Authors: Michaelis Laura A
Published: February 2008

The Natural Semantic Metalanguage (NSM) approach articulated by Uwe Durst is a componential theory of meaning, and it inherits many of the strengths of such theories. This is especially evident when we compare NSM with componential models that share its view of linguistic cognition as a reflex of the human meaning-making capacity in general. One such strength is the model's ability to account for prototype effects in categorization judgments without assuming scalar category membership or fuzzy category boundaries. Durst argues (section 3.3) that “[s]ince meaning is more than reference, one cannot conclude from referential fuzziness or vagueness that the meanings of words are fuzzy or vague as well”. The view is reminiscent of Lakoff's (1987) radial model of category structure, in which prototypicality ratings reflect not category structure but divergence of cognitive submodels that jointly define the best exemplars. Another strength of NSM that can likewise be traced to its decompositional base is its ability to capture cross-linguistic differences in lexical conflation patterns, as exemplified by Durst's comparison of words denoting anger in a variety of languages (section 3.3). Similarities and differences among the cognate words are captured by partial overlaps in their propositional representations, and what emerges is a relatively constrained picture of the range of typological variation. This is a strength that NSM shares with Talmy's (1985) model of motion-verb lexicalization patterns: these models allow otherwise ineffable translation problems to be described in rigorous ways. Just as Talmy's model enables us to talk about rhetorical-style differences among languages (or language families) by reference to fundamental features of event schematization (Slobin 1996), so the NSM approach captures ‘connotational’ differences among cognate lexical items that have been neglected in denotation-based lexicography.
About NSM: A general reply
Authors: Durst Uwe
Published: February 2008

1. Is NSM ‘scientific’?

The absence of technical terms and formal devices in NSM explications seems to invite some critics to dispute the scientific nature of the theory. In one example, Riemer2 states that “[the] commitment to naturalness seems contradictory because in other areas of investigation, the development of a ‘scientific’ (i.e. empirical and testable) theory necessitates the very type of technical, artificial vocabulary which NSM explicitly repudiates”. To support this criticism, Riemer refers to evolutionary theory and generative phonology. But evolutionary theory is about the development of natural species, and generative phonology investigates (the rules of) phonological representations on the basis of phonological features. Both disciplines can rely on physical data, and hypotheses can be tested on this physical basis. Even abstract phonological features such as [±vocalic] or [±grave] can be described in physical terms.
Pizzas und Pizzen – die Pluralformen (un)assimilierter Fremdwörter im Deutschen
Authors: Wegener Heide
Published: February 2008

The paper takes plural formation as an example of morphological assimilation of loanwords into the German inflectional system and shows that the assimilation process proceeds in two steps. German speakers first create intermediate plural forms with the non syllabic suffix -s, later the definite forms with a schwa suffix. Both kinds of plural forms are analysed in the framework of Optimality Theory. The forms created during the two stages are shown to follow from different hierarchies of wellformedness constraints and correspondence constraints respectively. Correspondence constraints are highly ranked for unassimilated borrowings as they are for peripheral word classes of proper names and onomatopoeia, by contrast, prosodic and phonological, esp. phonotactic wellformedness constraints are highly ranked for assimilated borrowings as they are for common nouns in the native lexicon. The shape of both kinds of plural forms will be shown to be functionally motivated. Whereas the schwa plural formation is rooted in the pressure for plural forms to be easy to articulate, the -s plural is rooted in the need for preservation of the sound shape of the stems: The syllabic schwa suffixes provide trochaic plural forms, words of optimal length with optimal syllable structure, the non syllabic -s provides structure preserving forms where the base is easy to recognize.
Behavior and Mechanisms of Irradiation—Thermal Creep of Cladding Tubes Made of Zirconium Alloys
Authors: Rogozyanov A. Ya. , Kobylyansky G. P. , Nuzhdov A. A.
Published: February 2008

The objective of this work was to study the irradiation-thermal creep behavior of cladding tubes made of two Russian zirconium alloys: the widely used E110 (Zr-1Nb) alloy and the advanced E635 (Zr-1Nb-1.2Sn-0.35Fe); and to demonstrate the advantages of E365 claddings for VVER fuel rod application with respect to fuel pellet-cladding gap at high burnups. For this purpose, a creep test concept and an analysis methodology were developed. Creep tests using cladding tubes made from both alloys were carried out. The test results along with published data allowed development of predictive models of irradiation-thermal creep for the cladding tubes of both alloys. The models describe strain processes in non-irradiated claddings and in claddings under and after irradiation. The models benchmark well to dimensional changes in VVER fuel rods. The models show the fuel pellet-cladding gap to disappear at higher burnup values if E635 is used for VVER cladding as opposed to the E110 alloy.
A Standardization Method for Respiratory Sinus Arrhythmia Using Breathing Frequency (the 2nd Report): Efficiency of Assessing Changes in Cardiac Parasympathetic Activity with Posture
Authors: Kageyama Takayuki , Imai Hideki , Kabuto Michinori
Published: February 2008

A Standardization Method for Respiratory Sinus Arrhythmia Using Breathing Frequency (the 2nd report) : Efficiency of Assessing Changes in Cardiac Parasympathetic Activity with Posture : Takayuki Kageyama, et at. Urban Environment and Health Project, National Institute for Environmental Studies Respiratory sinus arrhythmia (RSA) provides a noninvasive index of cardiac parasympathetic activity, although it appears to be modified by breathing frequency (BF) without any change in the tonic level of vagal activity. In the previous study, we proposed a statistical method for respiratory standardization of RSA amplitude at supine rest. Although RSA amplitude in other postures provide useful information on cardiac autonomic function or activity, they also appear to be modified by BF. We therefore examined RSA amplitude at sitting rest and that at standing rest as functions of BF intentionally maintained constant (0.180.33 Hz) for 1 1 nonsmokers (5 males and 6 females aged 19‐28) in order to develop similar respiratory standardization methods in those postures. In those postures, RSA amplitudes linearly decreased with the increase in BF on a log‐log scale, regardless of whether it was paced or nonpaced regular breathing. The respiratory modification of RSA amplitude at standing rest was greater than that at sitting rest, and both of them were greater than that at supine rest. This shows that RSA amplitude in the postures during nonpaced regular breathing can be statistically standardized based on the BF according to posture. Applying these methods to the data obtained from another experiment concerned with changes in RSA amplitude with posture, the efficiency of the standardization was confirmed.
Organic Solvents and the Kidney
Authors: Mutti Antonio
Published: February 2008

Organic Solvents and the Kidney: Antonio Mum. Laboratory of industrial Toxicology, University of Parma Medical School—The association between solvent exposure and chronic glomerulonephritis is still a controversial scientific issue. Almost all published case‐referent studies consistently show an association between chronic glomerulonephritis and exposure to volatile hydrocarbons. Two nested prospective studies and a recent case‐referent study also suggest a role of solvent exposure in the progression of renal changes towards chronic renal failure. Cross‐sectional studies carried out in groups of workers exposed to relatively low concentrations of single solvents or mixtures demonstrate tubular damage frequently associated with high molecular weight proteinuria and changes in the glomerular basal membrane. In some studies, immunological disturbances (increased titer of antilaminin and/or anti‐glomerular basement membrane antibodies) have been found. Whereas unequivocal evidence of solvent‐induced renal disturbances is apparent on a group basis, the health significance of such changes is difficult to assess at the individual level. Although renal cancer in the male rat chronically exposed to a variety of hydrocarbons including several organic solvents is not a good model for assessing human risk, experimental studies may not be used as a proof to exclude the cancerogenic properties of all organic solvents. Indeed, epidemiological investigations suggest that a small excess mortality from renal‐cell cancer may occur as a consequence of exposure to some organic solvents, including dry‐cleaning products and petroleum‐derived hydrocarbons. Despite consistent results indicating renal effects of solvent exposure, no specific agents appeared to be implied more frequently, neither dose‐ effect nor dose response relationships were found and, finally, possible risk factors accounting for an increased individual susceptibility were not identified. Early markers of renal damage are very useful to identify groups at risk, since these subtle abnormalities may represent an early stage of clinically silent but potentially progressive renal diseases. Follow‐up should confirm the observed changes and assess their course and prognostic meaning. Repeatedly positive markers of renal damage also indicate the need for intervention, including job counseling and removal from exposure.
The Role of Biomarkers in Detecting Early Changes Relating to Exposure to Occupational Carcinogens
Authors: Shaham Judith , Ribak Joseph
Published: February 2008

The Role of Biomarkers in Detecting Early Changes Relating to Exposure to Occupational Carcinogens: Judith Shaham et al. Occupational Cancer Unit, Occupational Health and Rehabilitation Institute at Loewenstein Hospital—Increasing evidence points to the role of chemical exposure in the etiology of cancer. Approximately 4% (1‐10%) of all deaths due to cancer are caused by occupational carcinogens. In recent years carcinogenic mechanisms have been equated with a continuum multistage process driven by carcinogen induced genetic and epigenetic damage. This process reflects the natural history of chemically induced neoplasia and is translated into the latency period. The development and implementation of laboratory techniques to detect biomarkers that reflect these changes provide opportunities for early diagnosis of both occult and preneoplastic tumors. In order to facilitate the use of biomarkers in the assessment of health risk, they have been divided into categories that represent the continuum between different stages involved in the carcinogenic process from exposure to disease. Thus, the focus of biomarkers has been on the internal dose, biological effective dose and biological response and their use has become an integral part of molecular epidemiology. Biomarkers are useful in strengthening the causality between exposure and malignant transformation or to serve as an indicator warning of a potential carcinogen when epidemiological data concerning the exposure‐disease relationship is inconclusive or unavailable. A battery of markers that reflect different stages of the carcinogenesis process can be used to provide information on the etiology of occupational cancer, to monitor exposed populations, and to identify high risk populations in order to encourage appropriate surveillance with regard to cancer prevention, although there are ethical issues regarding risk assessment.
Evidence for an Acceleration of Programmed Cell Death in Bronchiolar Epithelium after Exposure to O,O,S‐Trimethyl Phosphorothioate
Authors: Koizumi Akio , Naruse Mayumi , Hirosawa Iwao , Ohtomo Kazuo
Published: February 2008

Evidence for an Acceleration of Programmed Cell Death in Bronchiolar Epithelium after Exposure to O, O, S‐Trimethyl Phosphorothioate: Akio Koizumi, et al. Akita University School of Medicine—Exfoliation of Clara cells is a prelude to pathological alterations after exposure to a variety of toxicants. The reported morphological features of exfoliating Clara cells share similarity with some types of programmed cell death (PCD). The purpose of the present study is to characterize morphological changes in Clara cells in the process of PCD in physiological and pathological conditions. We used 0,0,S‐trimethyl phosphorothioate (OOS‐TMP) as a lung toxicant. Morphological changes in the lungs of control rats and rats killed at 2 to 48 hr after treatment with OOS‐TMP (po. 60 mg/kg) were investigated by electron microscopy. In situ DNA‐ fragmentation was determined by 3’‐OH end labeling in these rats. Immunoelectron microscopy was conducted to examine the morphological changes in Clara cells in PCD. Exfoliation of Clara cells started at 2 hr after dosing. At 6 hr, many Clara cells were sloughed. In situ DNA‐fragmentation positive cells were detected in the bronchiolar epithelium of both control and treated rats. Their relative incidences increased 13 fold by 6 hr and returned to basal levels by 48 hr. In contrast, no positive cells were detected in the alveolar cells of either group. Positive cells in the bronchiolar epithelium were identified exclusively as Clara cells. The ultrastructure of the DNA‐ fragmentation positive cells revealed similar changes in control and treated rats. DNA‐fragmentation, a hallmark of PCD, was detected in Clara cells of both control and treated rats, but not in alveolar cells. The relative increases in the DNA‐fragmentationpositive cells suggest an acceleration in PCD after treatment with OOS‐TMP. The results of this study indicate that different mechanisms of cellular death occur in Clara and alveolar cells in response to toxic insults. This difference most likely reflects the cell‐ specific mode of the action of lung toxicants.
A Survey of Blood Pressure in Cadmium‐Exposed Workers
Authors: Zhang Guicheng , Li Xuegui , Guo Baocheng , Tian Guojun
Published: February 2008

A Survey of Blood Pressure in Cadmium‐Exposed Workers. Guicheng Zhang, et al. Xin‐ xiang Occupational Institute—An investigation was performed on the prevalence of hypertension and hypotension among 362 cadmium‐exposed workers in a nickel‐cadmium battery factory with 526 control workers/farmers. Cadmium in urine was 1 2.5μg/l in the cadmium workers and 2.4μg/l in the control group. Increased risk of hypertension had not been found in the workers exposed to cadmium. The prevalence of hypotension which was 3.9% in cadmium workers was lower than that in the control group. Logistic regression analysis revealed that the odds ratio of hypotension was 0.26 cadmium‐exposed workers (p = 0.0004). The results showed that cadmium exposure could decrease the prevalence of hypotension.
A Standardization Method for Respiratory Sinus Arrhythmia at Supine Rest as an Index of Cardiac Parasympathetic Activity Using Breathing Frequency
Authors: Kageyama Takayuki , Imai Hideki , Kabuto Michinori
Published: February 2008

A Standardization Method for Respiratory Sinus Arrhythmia at Supine Rest as an Index of Cardiac Parasympathetic Activity Using Breathing Frequency: Takayuki Kageyama, et al. Urban Environment and Health Project, National Institute for Environmental Studies—Two spectral components of heart rate variability, respiratory sinus arrhythmia (RSA) and Mayer wave‐related sinus arrhythmia (MWSA) provide noninvasive indices of cardiac vagal activity and systemic sympathetic activity with vagal modulation, respectively. But the basic problem that breathing frequency (BF) appears to modify RSA without any change in the tonic level of vagal activity remains, indicating the need for respiratory standardization. In the present study, RSA amplitude at supine rest was examined as a function of BF intentionally maintained constant (0.18‐0.33 Hz) for 11 nonsmokers (5 males and 6 females aged 19‐28) with consideration of time after meals, which may affect RSA. The amplitude calculated by autoregressive spectral analysis linearly decreased with the increase in BF on a log‐log scale. This held in the case of RSA for nonpaced regular breathing with the mean BF corresponding to the center frequency of RSA. The amplitude during nonpaced regular breathing could therefore be statistically standardized to that at BF of, e.g., 0.25 Hz, which agreed well with that at the paced BF of 0.25 Hz (r = 0.958). This suggests a simple, efficient method for the reliable assessment of vagal activity based on RSA amplitude and of sympathetic activity indicated by the ratio of MWSA amplitude to RSA amplitude.
Acute and Subacute Inhalation Toxicity of Highly Purified Phosphine (PH3) in Male ICR Mice
Authors: Omae Kazuyuki , Ishizuka Chizuru , Nakashima Hiroshi , Sakurai Haruhiko , Yamazaki Kazuto , Mori Koji , Shibata Toshikatsu , Kanoh Hirokazu , Kudo Mitsuhiro , Tati Masatomo
Published: February 2008

Acute and Subacute Inhalation Toxicity of Highly Purified Phosphine (PH3) in Male ICR Mice: Kazuyuki Omae, et al. Department of Preventive Medicine and Public Health, School of Medicine, Keio University—The acute and subacute inhalation toxicity of highly purified phosphine (PH3, CAS No. 7803‐51‐2, 99.995%) in male ICR mice was investigated. LC50 for one‐hour exposure was greater than 59.2 ppm and that for four‐hour exposure was between 26.5 ppm and 33.4 ppm. Experiments involving acute exposure to 25 ppm PH3 for one, two, four or eight hours, and subacute exposure to 5 ppm PH3 for six hours/day, five days/week, for two or four weeks were conducted. All mice subjected to acute eight‐hour exposure died but a histopathological examination failed to reveal the actual causes of death. In the nasal cavity, exposure‐time related inflammatory changes were observed in the acute two‐, four‐, and eight‐hour exposure groups, and in the subacute four‐week exposure group. Other his‐ topathological, hematological, and serum biochemical examinations did not reveal PH3‐related changes. Further study is necessary to assess the actual effects of PH3 on the cause of death.
Biochemical Changes as Biomarkers of Pyrethroid Toxicity in Rats
Authors: Tong Jian , Tian Hai‐lin
Published: February 2008

Biochemical Changes as Biomarkers of Pyrethroid Toxicity in Rats:ToNG Jian, et at. Department of Public Health, Suzhou Medical College—Biochemical changes reflecting toxic effects of two pyrethroid pesticides were pursued under experimental conditions of single and multiple exposures. Two pesticides, fenvalerate and cypermethrin, were administered to rats, and biochemical indices such as levels of enzymes and proteins in blood and bron‐ choalveolar lavage fluid (BALF) were measured. Results indicated that with multiple oral administration of cypermethrin to rats, a significant decrease in blood cholinesterase (ChE) activity could be observed after 1 wk of daily treatment, which suggested a secondary and indirect response. On the other hand, lung damage induced by fenvalerate seemed to be an acute effect, since all the biochemical effects measured in the present study appeared within 1 d after the single exposure, and could no longer be detected 1 wk later. These findings indicated that biochemical changes in biological samples could be used as biomarkers, which in turn may provide a supplementary means for the recognition of potential adverse effects of the pesticides as well as for the protection of sensitive individuals in an occupational context.
Silicosis Caused by Rice Husk Ashes
Authors: Liu Shuchun , Liu Ning , Li Jie
Published: February 2008

Silicosis Caused by Rice Husk Ashes: Shuchun Liu, et al. School of Public Health, Harbin Medical Univeraity—The processing of rough rice (paddy) can produce rice husk which is about 20% of paddy. Rice husk is utilized as an energy resource in many countries. Rice husk ash is used to a great extent as an industrial raw material in the ceramic and metallurgical industries. A number of workers are exposed to rice husk ash dust. Whether rice husk ashes can cause pneumoconiosis and other adverse effects is still a problem awaiting solution. In this connection, we performed epidemiological, experimental and aetiological studies. Rice husk ash dust can cause silicosis characterized by diffuse interstitial fibrosis and nodules. The free silica content increased as the treatment temperature for rice husk rose, and so did cristobalite and tridymite content. When rice husk was treated at 1,300°C, free silica content amounted to 93.8%, of which cristobalite was 38.0% and tridymite 6.1%. These products are the main agents in the development of diffuse pulmonary fibrosis and silicotic nodules.
Analysis of the Expression of TcR Vβ Repertoires in Patients with Silicosis
Authors: Ueki Ayako , Nakashima Masamitsu , Kishimoto Takumi , Nakamura Junichiro , Kinugawa Keigo , Sakaguchi Haruko
Published: February 2008

Analysis of the expression of TcR Vß repertoires in patients with silicosis.: Ayako Ueki, et al. Department of Hygiene, Kawasaki Medical School—Several environmental factors have been reported to induce autoimmune diseases, e. g. progressive systemic sclerosis in the patients with silicosis. In previous papers, we reported the superantigenicity of silicate to human lymphocytes in vitro. This study was intended to determine whether the modulation of TcR Vß repertoires can be observed in peripheral blood lymphocytes from patients with silicosis. Twenty‐four patients with silicosis and 11 individuals who had no experience of exposure to silica dust donated periphral blood only after their informed consent was obtained. Peripheral blood mononuclear cells (PBMC) were separated from 10 m/ of blood by the Ficoll‐Hypaque density centrifugation method, stained with fluorescein isothiocyanate (FITC)‐conjugated monoclonal antibody specific to the TcR Vß repertoires, and analyzed flow cytometrically. The V/3 repertoires analyzed were Vß 5.3 + 5.2, 5.2, 5.1, 6.7, 8, and 12. Some distinct V/3 repertoires, V/3 5.2 + 5.3 and V/3 5.3 were predominantly but not significantly expressed in the peripheral blood lymphocytes from the patients compared with the control group, and at the same time the repertoire V/3 8 decreased in the patients, especially those with profusion rate (PR) 3. These results support the possibility that silicate acts as a superantigen in human beings as in the observations in vitro.
Estimation of Background Exposure to Toluene Using a Physiologically‐Based Kinetic Model
Authors: Pierce Crispin H. , Dills Russell L. , Lewandowski Thomas A. , Morgan Michael S. , Wessels Mike A. , Shen Danny D. , Kalman David A.
Published: February 2008

Estimation of Background Exposure to Toluene Using a Physiologically‐Based Kinetic Model: Crispin H. Pierce, et al. Department of Environmental Health, University of Washington—Estimation of environmental exposure to toxicants has generally been limited to concentration measurements in air, water, and foods. Measurement of background levels of toxicants in biological tissues for this purpose has been limited by analytical detection. After developing a sensitive headspace GC‐MS method, we conducted 33 controlled human exposures of 50 ppm 1Hg8‐toluene and 50 ppm 2H8‐toluene for 2 h, and measured concentrations in blood and breath for 100 h post‐exposure. Blood and breath samples from a separate cohort of 9 men exposed to 2H8‐toluene only were also measured for background 1H ‐toluene levels. A physiologically‐based kinetic (PBK) model, previously constructed and validated in an analysis of the 2H8‐toluene data, was used to predict the level of ambient 1H8‐toluene exposure that produced the observed breath levels. The model‐derived estimate of mean background 1H8‐toluene exposure was 47 ± 44 ppb (mean ± s.d.), which is consistent with indoor air measurements from this and previous studies of 3‐27 ppb and outdoor measurements of 2‐43 ppb. According to the PBK model, background exposure was expected to produce an average blood concentration of 5.9 nmol/l, which was within a measured range of 3‐16 nmol/l, and a corresponding alveolar air concentration of 310 nmol/m3, within a range of 138‐764 nmol/m3. This work extends the use of physiologic modeling to back‐predict environmental dose, and found that significant differences in inter‐individual 1H8‐toluene background exposures exist.
An Outbreak of Hematopoietic and Reproductive Disorders Due to Solvents Containing 2‐Bromopropane in an Electronic Factory, South Korea: Epidemiological Survey
Authors: Park Jung‐Sun , Kim Yangho , Park Dong Wook , Choi Kyeong Sook , Park Seung‐Hyun , Moon Young‐Hahn
Published: February 2008

An Outbreak of Hematopoietic and Reproductive Disorders Due to Solvents Containing 2‐Bromopropane in an Electronic Factory, South Korea: Epidemiological Survey: Jung‐Sun Park, et al. Industrial Health Research Institute, Korea Industrial Safety Corporation (KISCO)

Objectives

This survey was conducted to identify the causative agent in the outbreak in an electronic factory in Korea.

Methods

The questionnaire administered to subjects consisted of questions regarding medical and occupational history, including current work practices. Employees were also examined for liver, kidney, brain, reproductive organ and bone marrow function, etc. Detailed investigation of industrial hygiene was conducted to identify the potential source of occupational exposure.

Results

Among the three subject groups, all 23 intoxication cases (6 males and 17 females) were found in the only section using a new cleaning solution, the Tactile Switch Assembly Operation (total workers: 8 males and 25 females). Abnormal findings in the cases were only hypofunctions of the reproductive organs (ovarian failure, azoospermia or oligospermia) and the bone marrow (pancytopenia). 2‐bromopropane is the main component in the cleaning solution (97.4%). Until late November, 1994, workers were exposed to the cleaning solution directly without using proper protective equipment. The solvent was changed from Freon 113 to the above mixture solution in February, 1994. There has been no case among workers who quit before February, 1994. Freon 113 can therefore be excluded as a possible causative agent in the outbreak.

Conclusions

The outbreak in the section of Tactile Switch Assembly Operation was caused by exposure to the new cleaning solution. The causative agent is most likely to be 2‐bromopropane.
Ovarian Toxicity of 2‐Bromopropane in the Non‐Pregnant Female Rat
Authors: Kamijima Michihiro , Ichihara Gaku , Kitoh Junzoh , Tsukamura Hiroko , Maeda Kei‐ichiro , Yu Xiaozhong , Xie Zhenlin , Nakajima Tamie , Asaeda Nobuyuki , Hisanaga Naomi , Takeuchi Yasuhiro
Published: February 2008

Ovarian Toxicity of 2‐Bromopropane in the Non‐Pregnant Female Rat: Michihiro Kamijima, et al. Department of Hygiene, Nagoya University School of Medicine—A cluster of patients with amenorrhea, oligospermia and anemia were found among workers in an electronics factory in the Republic of Korea. 2‐Bromopropane was suspected to cause the disorders. This study aimed to clarify its ovarian toxicity in the virgin rat. Female Wistar rats were daily exposed to 0, 100, 300, or 1,000 ppm 2‐bromopropane for eight hours a day for 9 weeks. During the experimental period, vaginal smears were taken everyday to monitor ovarian cyclicity. Tissues were histopathologically examined and plasma concentrations of luteinizing hormone (LH) and follicle‐stimulating hormone (FSH) were determined at the end of experiment. The vaginal smear test showed that the number of normal cycles decreased significantly both in the 300 and 1,000 ppm groups. The histopathological examination revealed dose‐dependent ovarian follicle atresia accompanied by a decreased number of normal antral and growing follicles in the 300 and 1,000 ppm groups. Especially, in the ovaries of rats with persistent estrous smears in the 1,000 ppm group, most of the follicles were atretic and there were no newly formed corpora lutea. There still remained normal antral follicles and corpora lutea in the ovaries of the remaining rats of the group and of the 300 ppm group with constant diestrous and occasional estrous smears. Hormonal examination revealed no statistically significant change in LH or FSH concentrations between any groups. The results showed that 2‐bromopropane has ovarian toxicity in rats, indicating that the secondary amenorrhea in human cases was due to 2‐bromopropane exposure.
A Review on Toxicity of 2‐Bromopropane: Mainly on its Reproductive Toxicity
Authors: Takeuchi Yasuhiro , Ichihara Gaku , Kamijima Michihiro
Published: February 2008

A Review on Toxicity of 2‐Bromopropane : Mainly on its Reproductive Toxicity: Yasuhiro Takeuchi, et al. Department of Hygiene, Nagoya University School of Medicine—2‐Bromopropane has been used mostly as an intermediate for medicines, pesticides and other chemicals in closed systems. Recently it has come to be used as an alternative solvent in open systems instead of ozone layer depleting chlorofluorocarbons. An outbreak of reproductive and hematopoietic disorders occurred in workers exposed to solvents containing 2‐bromopropane in a Korean factory in 1995. After that some animal experiments revealed that 2‐bromopropane has a severe toxic effect on the female and male reproductive organs and hematopoietic organs. We reviewed the toxicity of 2‐bromopropane based on the recent data obtained in epidemiological surveys and animal experiments. Toxicities of structurally related bromopropanes were compared with that of 2‐bromopropane and its risk assessment was discussed. The conclusions are as follows: 1. 2‐Bromopropane has a specific reproductive and hematopoietic toxicity in both sexes in humans and experimental animals. 2. It could impair the testes, especially spermatogonia in males. 3. It could impair the ovarian function, resulting in a disturbed estrous cycle and loss of oocytes in females. 4. It could impair the bone marrow, resulting in pancytopenia. 5. It has a weak potent mutagenicity in bacterial mutation assays. 6. A risk assessment suggests that around 0.3‐10 ppm might be recommended as an occupational exposure limit for 2‐bromopropane.
A Study on Extremely Low‐Frequency Electric and Magnetic Fields and Cancer: Discussion of EMF Safety Limits
Authors: Nakagawa Masayoshi
Published: February 2008

A Study on Extremely Low‐Frequency Electric and Magnetic Fields and Cancer: Discussion of EMF Safety Limits: Masayoshi Nakagawa, Railway Technical Research Institute—Since Wertheimer and Leeper reported in 1979 that the incidence of cancer in children living near distribution lines is twice or three times as high as normal, the association between leukemia or cancer and extremely‐low‐frequency (ELF) electric and magnetic fields (EMF, electromagnetic fields) has often been the subject of debate. Compared with the thermal effect of high frequency bands, the non‐thermal effects of ELF‐electromagnetic fields on animals are very weak and have been studied in the recent past. A positive correlation between low level ELF electromagnetic fields and some specific cancers was detected by epidemiological studies but not directly by laboratory experiments. Nevertheless it has been reported that very low‐level (0.1μT order) ELF electromagnetic fields can induce cell proliferation and a high transcription rate in human lymphocytes and human carcinoma cell lines. However, more investigations are necessary to arrive at an appropriate conclusion as to whether a low level ELF electromagnetic field induces mutation or acts as a promotor of cancer.

In the last two decades, equipment using high power EMF e.g. pulse magnetic fields have come into common use and the effects of eddy currents, which are induced by the time‐varying magnetic fields, in humans and animals are clearly noticed. These effects are magnetophosphenes, spastic contraction of muscles and stimulation of nerves. In 1990, the American Conference of Governmental Industrial Hygienists (ACGIH) published the threshold limit values (TLV) of ELF magnetic fields as a function of 60/f (frequency) mT while in 1993 the National Radiation Protection Board (NRPB of the UK) published 80/f mT safety guideline. These magnetic flux densities i.e. 1.2 mT at 50 Hz recommended ACGIH or 1.6 mT at 50 Hz by NRPB were calculated so as to obtain a current density of 1‐10 mAm’2 i.e. the supposed minimum electric current to affect animals. While these recommended values are 100 to 1,000 times higher than the flux density levels in our living environment, the suggested value that epidemiologists think has deleterious effects on humans is 0.2μT. It is difficult to decide which is the right guideline to adopt: the one suggested by the results of epidemiological surveys indicating that very low‐level EMF raises the incidence of leukemia and other cancer, or the one which was recommended as the minimum level of magnetic flux density inducing a current that would supposedly affect humans and animals. Therefore this disparity between the values arrived at by epidemiological surveys and that recommended by regulatory agencies has to be resolved.
Role Perception and Expectation of Occupational Health Nursing from a Survey in North Carolina
Authors: Sato Naoko
Published: February 2008

Role Perception and Expectation of Occupational Health Nursing from a Survey in North Carolina: Naoko Sato, Tokyo Women's Medical College. School of Nursing—A descriptive study was conducted of 32 occupational health nurses working in North Carolina, 54 of their employers and 87 of their company employees. By using self‐administered questionnaires, subjects were assessed as to the level of performance in 16 occupational health nursing activities to examine their current perceptions and future expectations for occupational health nursing roles. It was found that occupational health nurses currently perform numerous activities, such as direct care services, administrative tasks for the management of the occupational health department, and collaborative tasks with other health disciplines. Comparing the perceptions in the three groups, employees perceived greater needs than nurses with respect to planning and developing educational programs (p<0.05) and conducting research (p<0.01), whereas employers perceived the occupational health nursing roles similarly to nurses. Occupational health nurses, employers and employees had high expectations for the future in all activities. Among 16 activities, in particular, health policy development was reported as the priority activity by the nurses, in which they reported a significantly higher mean score for expectation than the employers (p<0.05). The results from this study indicate that occupational health nurses should have their autonomy increased in developing and managing high quality occupational health nursing. Occupational health nurses need to develop their ideal roles to meet the high expectations of employers and employees.
Effects of Intratracheally Administered Indium Phosphide on Male Fischer 344 Rats
Authors: Uemura Takamoto , Oda Kenichi , Omae Kazuyuki , Takebayashi Toru , Nomiyama Tetsuo , Ishizuka Chizuru , Hosoda Kanae , Sakurai Haruhiko , Yamazaki Kazuto , Kabe Isamu
Published: February 2008

Effects of Intratracheally Administered Indium Phosphide on Male Fischer 344 Rats: Takamoto Uemura, et al. Department of Preventive Medicine and Public Health, School of Medicine, Keio University—Objective—To examine the effects of intratracheally administered indium phosphide (InP) and distribution of indium on male Fischer 344 rats. Materials and methods—Rats were intratracheally given 0, 1, 10 or 100 mg/kg of InP with a mean diameter of 0.8pm and observed for 1 and 7 days. The bronchoalveolar lavage fluid (BALF) was examined biochemically and cytologically. Serum biochemical, hematological and histopathological examinations were done, and the indium concentration in organs and serum was determined. Findings—The number of neutrophils in BALF remarkably increased in a dose‐effect manner 1 and 7 days after administration and InP particles were phagocytized in the macrophages. Total protein (TP), lactate dehydrogenase (LDH), total phospholipid (TPL) and total cholesterol (T‐Cho) in BALF showed a clear dose‐effect relationship 7 days after administration. Indium was detected in the liver and spleen and increased in a dose‐related manner on the next day and 7 days after administration. Serum indium was detected in the group given more than 10 mg/kg but did not reveal a dose relationship. Histopathological examination of the lungs showed phagocytized InP particles in the macrophages and the migration of neutrophiles in the alveoli. InP particles remained in the bronchioles and alveoli until 7 days after. No histopathological changes were detected in the liver or spleen. A hematological study did not reveal significant findings, interpretation—Intratracheally administered InP particles cause pulmonary inflammation and those particles remain in the lower airways for at least 7 days. Phagocytosis of macrophages may contribute to their disposal and distribution to the liver and spleen. Further study is required with particles with a lower toxic activity than InP and with the same particle size as the InP used in this study, to clarify their specific toxicity. Simultaneously longer observation is needed to assess toxicity in the other organs after distribution.
Intraocular Pressure, Ocular Hypertension, and Glaucoma: A Comparison of White and Blue Collar Workers
Authors: Qureshi Imran Ahmad , Xi Xiao Rong
Published: February 2008

Intraocular Pressure, Ocular Hypertension, and Glaucoma: A Comparison of White and Blue Collar Workers: Imran Ahmad Qureshi, et al. Department of Physiology, Rawalpindi Medical College—The course of glaucoma is an insidious one and most cases remains asymptomatic until the visual field has been seriously diminished. Consequently, it is a disease suited to a preventive approach. The intraocular pressure (IOP) distribution and prevalence of ocular hypertension and glaucoma have never been described in industrial workers. After controlling all IOP affecting factors, we investigated levels of intraocular pressure and its association with certain health parameters along with the prevalence of ocular hypertension and glaucoma in healthy white and blue collar workers in Karachi, the largest city in the Islamic Republic of Pakistan. In both groups, the histogram shows a skew to the right, so that the distribution was not Gaussian. This study reports that on an average, per decade, white collars have 1.1 mmHg (p<0.001) higher IOP than blue collar subjects. The average per decade increases were 0.47 mmHg and 0.33 mmHg in white and blue collar workers respectively. The age effect was statistically insignificant until the age of 40 years in both groups, after which it became quite significant. Differences in mean IOP (left minus right) were found to be 0.15 mmHg (p<0.2), and 0.12 mmHg (p<0.05) in white and blue collar subjects, respectively. In normal subjects IOP was weakly but statistically significantly correlated with the heart rate and systolic blood pressure. Heart rate, systolic and diastolic blood pressures and age were found to be risk factors for ocular hypertension. In both normotensive and ocular hypertensive subjects, weight and height were not correlated significantly. Ocular hypertensive subjects (IOP>21 mmHg) were 2.48 times more numerous in white collar than in blue collar subjects. Most of the ocular hypertensive and several glaucoma patients were diagnosed during this survey. The results therefore strongly suggest that in routine health examination, tonometry should be included.
Prolonged Standing and Physical Exertion at Work during Pregnancy Increases the Risk of Preterm Birth for Thai Mothers
Authors: Ritsmitchai Skulrat , Geater Alan F. , Chongsuviwatvong Virasakdi
Published: February 2008

Prolonged Standing and Physical Exertion at Work during Pregnancy Increases the Risk of Preterm Birth for Thai Mothers : Skulrat Ritsmitchai, et al. Epidemiology Unit, Faculty of Medicine, Prince of Songkla University—Women in Thailand are increasingly engaged in work which requires prolonged standing and physical exertion. Previous reports are inconclusive regarding the association between prolonged standing during pregnancy and preterm birth. A matched case‐control study was conducted at Hat Yai Hospital, Songkhla, Thailand, between May 1 and November 30, 1993, to determine whether prolonged standing and/or physical exertion during pregnancy are associated with preterm birth. Cases were mothers with a singleton preterm infant and controls were mothers with a singleton term infant giving birth following the case and matched with the case on age (case age±5 years) and parity. Two hundred and twenty‐three case‐control pairs were recruited. Indicators of work activity and other potential risk factors including socioeconomic status, maternal stress, medical complications, and obstetric problems were ascertained through the medical records and by questionnaire‐based interviews administered to each eligible subject immediately after delivery. Conditional logistic regression was employed for multivariate analysis. After adjustment for pregnancy complications, previous preterm birth, physical exertion and physical exercise, a significant association between prolonged standing longer than 3 hr per day throughout gestation and preterm birth was demonstrated, with an odds ratio of 4.10 (95% Cl, 1.29, 13.10) when compared to no prolonged standing. Physical exertion throughout pregnancy was also an independent risk factor of preterm birth (OR = 2.91, 95% Cl, 1.29, 6.58). In summary, standing longer than 3 hr per day at work throughout pregnancy, or lifting more than 10 kg weight at work, significantly increased the risk of preterm birth.
2‐Bromopropane‐Induced Hypoplasia of Bone Marrow in Male Rats
Authors: Nakajima Tamie , Shimodaira Shigetaka , Ichihara Gaku , Asaeda Nobuyuki , Kumazawa Toshihiko , Iwai Hisakazu , Ichikawa Ichihito , Kamijima Michihiro , Yu Xiaozhong , Xie Zhelin , Kondo Hidetaka , Takeuchi Yasuhiro
Published: February 2008

2‐Bromopropane‐lnduced Hypoplasia of Bone Marrow in Male Rats: Tamie Nakajima, et al. Department of Hygiene, Shinshu University School of Medicine—The hematotoxicity of 2 ‐bromopropane was investigated in thirty‐six male Wistar rats. The rats were put into four groups: three groups were exposed to 0, 300, and 1,000 ppm 2‐bromopropane for 8 hr per day, for 9 weeks, respectively, and the remaining group was exposed to 3,000 ppm only for 9‐11 days. Hematotoxicity was assessed by measuring peripheral blood cells as well as cellularity, the number of megakaryocytes and morphological findings in the bone marrow. Exposure to 2‐bromopropane decreased the numbers of erythrocytes in the peripheral blood at 300 ppm or higher, leukocytes at 1,000 ppm, and platelets at 300 and 1,000 ppm. Exposure to 300 ppm 2‐bromopropane did not influence the indices of bone marrow toxicity. Exposure to 1,000 ppm 2‐bromopropane or a higher dose‐dependently induced a hypoplastic profile with replacement of fatty spaces in the bone marrow, though the durations of exposure to 3,000 ppm were under one sixth. These exposures also induced dose‐dependent decreases in the number of megakaryocytes, with the maintained ratio of granulocytes to erythrocytes in the bone marrow. Residual progenitor cells showed some dysplastic or megaloblastic changes. These results suggest that exposure to 2‐bromopropane leads to a reduction in the numbers of hematopoietic cells in the bone marrow, the result being a persistent pancytopenia in male rats.
The Relationship between the White Blood Cell Count and Cigarette Smoking among Japanese Males
Authors: Momose Yoshito , Une Hiroshi , Ikui Haruhiko , Esaki Hiroji
Published: February 2008

The Relationship between the White Blood Cell Count and Cigarette Smoking among Japanese Males: Yoshito Momose, et al. Department of Hygiene and Preventive Medicine, School of Medicine, Fukuoka University—The cross‐sectional data for 1,155 men aged 20‐59 years obtained during annual health checkups in 1993 were used to study factors related to the WBC count. Current smokers have a WBC count averaging IQ‐15 percent higher than those of both ex‐smokers and those who never smoked. The current number of cigarettes smoked per day and the Brinkman index were also positively related to the WBC count after adjusting for such risk factors as the BMI, diastolic blood pressure, and HDL‐C level by means of a covariance analysis. We thus confirmed that an elevated WBC count is independently associated with the amount and duration of cigarette smoking among Japanese males.