Respiratory effects and skin allergy in workers exposed to tetrachloroisophthalonitrile.
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Biomedical subjects
Publications and source records attributed to K Aoyama.
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Two-dimensional crystals of soluble proteins were formed at the interface between an aqueous solution of proteins and a thin organic liquid (dehydroabietylamine). Proteins were adsorbed to the interface from the aqueous side and formed a two-dimensional crystal under suitable conditions. This method offers the advantage of great surface mobility and ideal homogeneity. Furthermore, the positive charge attracted negatively charged proteins well to the interface and no denaturation of the proteins was observed. With this technique, two-dimensional crystals of ferritin, catalase, chaperonin and 50S ribosome were prepared and their structural features were determined.
We present a case of synchronous triple primary lung cancer. 69-year-old male admitted after mass examination with the tumor shadows on right S3, left S4 and left S8. Further examinations confirmed as squamous cell carcinoma of right S3 and left S8 and as benign tumor of left S4 with right hillar lymph nodal swelling. In addition to these lesion, bronchofiberscopy revealed the squamous cell carcinoma of left basal bronchus. The secondlook operation was planned for bilateral primary lung cancer. At first, patient underwent right S3 segmentectomy with regional lymph nodes dissection. Two month later, left thoractomy was performed, followed by left lower lobectomy. Histopathological examination defined as well differentiated squamous cell carcinoma, moderately differentiated squamous cell carcinoma, squamous cell carcinoma in situ and hamartoma for right S3, left S8, left basal bronchus and left S4, respectively. Lymph node metastasis was found only in #121. Although tumors were resected with good curability, respiratory function was depressed and performance status deteriorated. It is important to attention to the preservation of respiratory function for the surgical treatment to multiple lesions and the combined therapy with radiation, chemotherapy and/or laser may be considered.
An animal exposure experiment which simulated a workplace exposure situation was made to compare toluene diisocyanate (TDI) concentrations which resulted in antibody production with those which elicited pulmonary responses. Groups of guinea pigs were exposed to inhaled TDI from 0.02 to 1.0 ppm (micrograms/g) for 3 h/day on 5 consecutive days. Three weeks later the animals were challenged with 0.02 ppm of free TDI for 15 min. TDI specific antibodies and pulmonary responses were evaluated. Specific antibody production showed a linear correlation to TDI concentration at induction. Most of the animals exposed to TDI levels above 0.2 ppm displayed significant pulmonary responses, but no correlation was found between TDI concentration at induction and the intensity of pulmonary response upon challenge to free TDI. These results indicated that there was a threshold concentration of 0.02 ppm TDI for antibody production and for the development of pulmonary response. It was also found that exposure to TDI at a level lower than its threshold concentration for sensitization may elicit a response in previously sensitized individuals.
The cps cluster of Escherichia coli K-12 comprises genes involved in synthesis of capsular polysaccharide colanic acid. Part of the E. coli K-12 cps region has been cloned and sequenced and compared to its Salmonella enterica LT2 counterpart. The cps genes from the two organisms are homologous; in the case of the LT2 genes, with G+C content of 0.61 and codons characteristic of high G+C species, it seems clear that they have been acquired relatively recently by lateral transfer from a high G+C species. The K-12 form of these cps genes is closely related to those of LT2 so must derive from the same high G+C species, but it appears to have transferred much earlier such that random genetic drift has brought P3 (the corrected G+C content of codon base 3) down from 0.77 to 0.64, more than halfway to the E. coli average of 0.57. We estimate, using an equation developed by Sueoka, that the lateral transfer to E. coli took place approximately 45 million years ago. This is the first report we are aware of demonstrating the expected adjustment of P3 after lateral transfer between species with different G+C content DNA.
The delayed-type allergenicity of triforine (Saprol), 1,4-bis (2,2,2-trichloro-1-formamidoethyl) piperazine, was studied. In a mass examination of chrysanthemum growers among whom triforine was commonly used, the highest rate of positive patch test reaction was seen to triforine (17%) among the 7 pesticides and chrysanthemum extracts tested. A higher prevalence rate of work-related skin symptoms was seen in subjects with a positive patch test reaction to triforine (44%) than in those with negative reactions to all allergens tested (15%) (p < 0.05). 12 subjects (67%) with positive patch test reactions to triforine were also positive to dichlorvos (DDVP), with a high kappa coefficient (0.65). The grading of guinea pig maximization test to triforine was grade IV (66%), defined as "strong". Cross-sensitization between triforine and dichlorvos was also shown. The present results confirm that triforine is capable of including delayed-type allergy among chrysanthemum growers and of showing cross-reactivity with dichlorvos.
We examined whether distress responses of rats would be a negative reinforcer or not. In Experiment 1, two rats were placed in adjacent compartments. One rat was reinforced by a food pellet for pressing either of two levers. One of the levers produced food while the other produced food plus electric shock (0.5-2.0 mA) to the other rat. All rats preferred the former lever. In addition, this tendency was more prominent in rats that had experienced shock previously than those without experience. In Experiment 2, one lever produced food while the other produced food plus auditory stimuli, a recorded distress scream (65 dB) or a pure tone (3 kHz, 65 dB). Rats that chose between food and food plus another rat's scream avoided being exposed to the scream. Rats that chose between food and food plus the pure tone chose the two levers equally. These results suggest that negative emotional responses of the conspecifics could be a negative reinforcer.
A non-staining bacterial flagellum filament only 24 nm in diameter has been observed clearly by using a phase-shifting electron holographic technique. This method produces a sufficiently high contrast in-focus image that could never be obtained by ordinary transmission electron microscopic (TEM) methods.
We report a case of localized cardiac tamponade after aortic valve replacement. A 56-year-old man had an aortic valve replacement for his aortic valve steno-insufficiency. At 3-postoperative day, severe hypotension occurred, causing acute renal failure. There were no cardiomegaly, high central venous pressure, nor echo-free space. A mass shadow, appearing on chest X-ray at 37-postoperative day, was diagnosed as a localized tamponade by means of a computed tomography and a radioangiography at 38 postoperative day. After the spontaneous drainage of old bloody effusion from the partially opened wound in mid-line, his cardiac and renal failure improved rapidly. When the hematoma is localized, computed tomography is most diagnostic while conventional echo-cardiography often fails to show echo-free spaces.
Groups of guinea pigs were exposed via inhalation to toluene diisocyanate (TDI) ranging from 0.02 to 1.0 ppm for 3 h/day on 5 consecutive days. Three weeks later, guinea pigs were challenged with TDI-GSA conjugates. Evaluations were based on TDI specific antibodies, pulmonary response and antigen stimulated histamine release from lung mast cells (LMC). The results indicated that both the antibody titer and the severity of pulmonary response followed a concentration-dependent pattern, with corresponding threshold levels. Antibodies and pulmonary responses were undetectable in animals exposed to 0.02 ppm TDI; however, exposure to 0.2 ppm TDI resulted in significant antibody production and pulmonary responses. Animals showed higher antibody titers and more severe pulmonary responses as TDI concentration increased from 0.6 ppm to 1.0 ppm. A discrepancy which was noted between antibody production and pulmonary responses was thought to be relevant to the discrimination of the potentials of antigen stimulated histamine release from LMC mediating between these two responses.
The replication region of the 2.77-kilobases (kb) plasmid pST1 from Streptococcus thermophilus No. 29 was identified. Deletion derivatives of pST1 were introduced into plasmid-free S. thermophilus No. 29 and examined for their ability to replicate autonomously. The nucleotide sequence had one open reading frame encoded for a 315 amino acid protein (Rep). Comparisons with proteins encoded by other Gram-positive bacterial plasmids strongly suggest that the deduced protein (RepS) encoded by pST1 has a replicative role. pST1 also contains a DNA sequence similar to the origin nick sequences of pLP1 or pLAB1000, which initiate plasmid replication at the plus origin. In a maxicell system, E. coli CSR603 carrying pSTUC4 produced a protein that was considered to correspond to the product of the RepS gene. These results strongly suggest that pST1 is replicated following a rolling-circle mechanism via single-stranded DNA intermediates.
The first total syntheses of disialoganglioside GD1 alpha and its alpha 2-6 positional isomer are described. Suitably protected pentasaccharide derivatives, derived from known pentasaccharide precursors, were selected as the glycosyl acceptors. Using our facile method of stereoselective alpha-glycosidation of sialic acid, these acceptors were coupled with methyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-D-galact o-2- nonulopyranosid)onate in acetonitrile medium in the presence of dimethyl(methylthio)sulfonium triflate (DMTST) to get the desired di-alpha-sialyl hexasaccharide derivatives in moderate yields. The hexasaccharide trichloroacetimidates upon coupling with (2S,3R,4E)-2-azido-3-O-benzoyl-4-octadecene-1,3-diol gave the corresponding beta-linked sphingosine glycosides in high yields. These were subjected in sequence to selective reduction of the azido group and coupling of the thus formed amino group with octadecanoic acid, O-deacylation, and saponification of the methyl ester groups to obtain ganglioside GD1 alpha and its positional isomer having the main-chain residue 2-6 linked.
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A total of 18 patients with hepatocellular carcinoma (HCC) were treated by transcatheter arterial embolization (TAE) with a 4'-epi-doxorubicin (EDX)-lipiodol emulsion. Infusion of the EDX-lipiodol emulsion (EDX-L) via the hepatic artery was followed by the injection of gelatin sponge in 12 cases. The response and survival of these 12 patients following EDX-L treatment were compared with those of 42 subjects treated with a doxorubicin-lipiodol emulsion (DX-L) and those of 23 patients treated by TAE with gelatin sponge (GS) only. In the group treated with EDX-L, nine cases were AFP-positive in sera and four showed a decrease in serum AFP values to less than 10% of the pretreatment level. Seven cases showed a partial response, and nine cases showed no change in the size of the tumor. In the group treated with EDX-L, nine cases are alive, and the oldest has survived for more than 431 days since the treatment. The half-year survival value was 57%, and the 1-year survival value was 49%. These values did not differ significantly from those calculated for the group treated with DX-L. The 1-year survival value determined for patients treated with a lipiodol emulsion (EDX-L or DX-L) followed by GS was 65%, and the 2-year survival value was 39%. These results rates are significantly better than those obtained in patients treated with GS only (1-year survival, 39%; 2-year survival, 13%.
Three statis growers complaining of immediate allergic symptoms induced by harvesting statis in a plastic greenhouse were examined to clarify their allergic conditions. Distinct positive reactions in the intradermal test and nasal and eye provocation test to the statis extracts were shown in all three cases. High score of radioallergosorbent test (RAST) IgE and remarkable RAST inhibitory effects to the statis extracts were seen in these cases. The immunologic cross-reactivity between statis and chrysanthemum was absent in the RAST inhibition in the patient labeled case C who had complained of the same allergic symptoms when handling chrysanthemums in the off-season for harvesting statis. Those results indicated that the allergic conditions of the present cases were from an immediate type of allergy mediated by a specific IgE antibody to the statis extract.
A 42-year-old female shiitake grower was investigated to clarify the etiology of skin lesions which developed during the planting of shiitake hyphae into bed logs. She complained of repeated eczematous skin lesions during the planting season, from March to July, for 10 years. She handled 7,000 pieces of small conic blocks made of beech, with shiitake hyphae attached to their surface, per day, and 300,000 pieces altogether per season. She was positive on patch testing with extracts of shiitake hyphae. In contrast, female shiitake growers with skin lesions associated with work other than planting, and without skin lesions, were negative on patch testing to the hyphae. Moderate allergenicity was observed to extracts of shiitake hyphae in a guinea pig maximization test. These findings indicated the etiology of skin lesions in shiitake growers to be allergic contact dermatitis induced by shiitake hyphae.
Skin blood flow in allergic contact reactions and cross-sensitivity were evaluated using laser Doppler flowmetry (LDF) to study the dose-response relationships in phases of induction and challenge in guinea pigs. Guinea pigs were sensitized with different doses of 1-chloro-2,4-dinitrobenzene (DNCB) and challenged with different doses of DNCB and 2,4-dinitrobenzene sulfonic sodium salt (DNBS). The skin reactions were evaluated by LDF and visual reading score. The results indicated that there were dose-response relationships between the doses of DNCB and LDF measurements in both phases of induction and challenge, that there was a cross-reaction between DNCB and DNBS, and that the reactions at 24 h were greater than that at 48 h after removal of the patches. LDF may discriminate between positive patch test reactions and negative or doubtful reactions, but not between weak positive and strong positive reactions. This is because vascular dilatation and increase of flow already reaches a maximum in weak reactions. The more advanced phases are dominated by oedema formation. This is simply the nature of the inflammatory reaction, rather than a methodological error. The important point is that LDF can separate positive reactions from negative/uncertain reactions. The results indicated that LDF, as a non-invasive technique, may objectively and quantitatively evaluate the dose-response relationships of contact sensitivity of sensitizers.
The present report describes experimental studies on the proteolytic activity of the secretion on the surface of okra pods and the allergenicity of okra components, to clarify the etiology of skin lesions due to okra. Proteolytic activity was detected on the surface of immature okra pods and seemed to be sufficient to cause the skin lesions. Further, in vivo, intradermal injection of the enzyme solution prepared from immature okra pods led to increased capillary permeability in guinea pigs, in contrast to heated preparations. The fraction purified by preparative paper chromatography from an ethyl acetate extract of okra pods showed moderate allergenicity in the guinea pig maximization test. The present experimental evidence supports our suggestions from previous surveys that the proteolytic enzyme of okra may be responsible for development of skin lesions, and that allergic contact dermatitis may also play a part in addition to irritant contact dermatitis.