Molecular docking and simulation studies of 3-(1-chloropiperidin-4-yl)-6-fluoro benzisoxazole 2 against VP26 and VP28 proteins of white spot syndrome virus

White spot syndrome virus (WSSV), an aquatic virus infecting shrimps and other crustaceans, is widely distributed in Asian subcontinents including India. The infection has led to a serious economic loss in shrimp farming. The WSSV genome is approximately 300 kb and codes for several proteins mediating the infection. The envelope proteins VP26 and VP28 play a major role in infection process and also in the interaction with the host cells. A comprehensive study on the viral proteins leading to the development of safe and potent antiviral therapeutic is of adverse need. The novel synthesized compound 3-(1-chloropiperidin-4-yl)-6-fluoro benzisoxazole 2 is proved to have potent antiviral activity against WSSV. The compound antiviral activity is validated in freshwater crabs (Paratelphusa hydrodomous). An in silico molecular docking and simulation analysis of the envelope proteins VP26 and VP28 with the ligand 3-(1-chloropiperidin-4-yl)-6-fluoro benzisoxazole 2 are carried out. The docking analysis reveals that the polar amino acids in the pore region of the envelope proteins were involved in the ligand binding. The influence of the ligand binding on the proteins is validated by the molecular dynamics and simulation study. These in silico approaches together demonstrate the ligand's efficiency in preventing the trimers from exhibiting their physiological function.

Development of simple, rapid and sensitive detection assay for grouper nervous necrosis virus using real-time loop-mediated isothermal amplification

A quantitative rapid detection method based on loop-mediated isothermal amplification has been developed for red-spotted grouper nervous necrosis virus (RGNNV). The nested polymerase chain reaction (PCR) assay is the mainstream inspection of the brooder in the hatchery. In this study, a real-time loop-mediated isothermal amplification (LAMP) method has been applied for RGNNV detection, known as a high-speed gene amplification procedure. Of the three temperatures (60 °C, 63 °C and 65 °C) attempted, it has been found that 63 °C is giving higher amplification from 11th minute onwards. Sensitivity analysis performed in comparison with real-time polymerase chain reaction, reverse transcriptase PCR and nested RT-PCR using various concentrations of template revealed that real-time LAMP method is efficient in terms of cost and time consumption. Specificity analysis revealed that the method developed is specific to RGNNV, whereas it has sequence cross-match with tiger puffer NNV giving advantage in detecting both the viruses. This method could be much efficient in analysing RGNNV in combination with TPNNV.

Cloning and expression of a surface immunogenic protein in Streptococcus dysgalactiae isolated from fish and its application in enzyme-linked immunosorbent assays to diagnose S. dysgalactiae infections in fish

Lancefield group C Streptococcus dysgalactiae (GCSD) causes severe necrotic lesions in the caudal peduncle in the genus Seriola farmed in Japan. To develop a sero-diagnostic method for GCSD infection in farmed fish, we attempted to identify a surface immunogenic protein that induces an antibody after infection with GCSD by immunoblot analysis using sera collected from infected fish. A protein obtained from sodium dodecyl sulfate (SDS) extracts of GCSD was identified as S. dysgalactiae surface immunogenic protein (Sd-Sip). Sd-Sip exhibited more than 94% homology with a surface antigen or a hypothetical protein from S. dysgalactiae mammalian isolates at the nucleotide sequence level. Expression of the recombinant Sd-Sip (rSd-Sip) was confirmed by immunoblot analysis, that is, its reactivity to GCSD-infected sera. Antibody detection ELISA using rSd-Sip and their usefulness for diagnosis of GCSD infection were examined. GCSD-infected sera collected from farmed amberjack, Seriola dumerili (Risso), showed strong reaction with immobilized rSd-Sip. Meanwhile, sera immunized by other pathogenic bacteria of fish were showed ELISA values similar to those of non-infected sera. These results of this study suggest that the antibody detection ELISA using rSd-Sip is an effective diagnostic method for GCSD infection in fish.

Isolation of lactic acid bacteria from kuruma shrimp (Marsupenaeus japonicus) intestine and assessment of immunomodulatory role of a selected strain as probiotic

Fifty-one lactic acid bacteria (LAB) strains were isolated and identified based on 16S ribosomal DNA sequence from the intestinal tracts of 142 kuruma shrimps (Marsupenaeus japonicus) collected from Kanmon Strait, Fukuoka and Tachibana Bay, Nagasaki, Japan. Cellular immunomodulatory function of 51 isolated LAB strains was assessed by measuring the level of interferon (IFN)-γ induction in mouse spleen cell culture. The strain Lactococcus lactis D1813 exhibited the highest amount of IFN-γ production and also bactericidal activity and was selected for testing its immunomodulatory role as a probiotic in kuruma shrimp. We also assessed the effect of dietary incorporation of this probiotic on resistance to Vibrio penaeicida infection in the kuruma shrimp. Our results demonstrate that probiotic L. lactis D1813-containing diet-fed (10⁵ cfu g⁻¹) shrimps displayed a significant up-regulation of lysozyme gene expressions in the intestine and hepatopancreas. However, insignificantly higher expression of anti-lipopolysaccharide factor, super oxide dismutase, prophenoloxidase, and toll-like receptor 1 was recorded in the intestine of shrimps fed the probiotic diet. Moreover, significantly increased (P < 0.01) resistance to the bacterial pathogen in term of better post-infection survival (61.7 %) was observed in the shrimps fed with the probiotic-incorporated diet compared with the control diet-fed group (28.3 %). The present study indicates the immunomodulatory role of the LAB L. lactis D1813 on the kuruma shrimp immune system and supports its potential use as an effective probiotic in shrimp aquaculture.

The SOCS and STAT from JAK/STAT signaling pathway of kuruma shrimp Marsupenaeus japonicus: molecular cloning, characterization and expression analysis

Signal transducer and activators of transcription (STAT) gene, suppressors of cytokine signaling (SOCS) has been isolated from kuruma shrimp, Marsupenaeus japonicus and characterized. The kuruma shrimp STAT (MjSTAT) cDNA was composed of 2901 bp consisting of 801 amino acid residues which includes a protein interaction domain, all alpha domain, DNA binding domain and SH2 domain. Homology analysis of MjSTAT showed 94.1% and 34.0% identities with Penaeus monodon STAT (PmSTAT) and Drosophila melanogaster STAT92E (DmSTAT), respectively. The kuruma shrimp SOCS (MjSOCS) cDNA was composed of 1675 bp consisting of 342 amino acid residues including a SH2 domain and C-terminal SOCS domain. Homology analysis of MjSOCS showed 52.6% and 21.3% identities with Chinese mitten crab (Eriocheir sinensis) SOCS2 and fruit fly (D. melanogaster) SOCS44A, respectively. The MjSTAT and MjSOCS genes are constitutively expressed in the muscle, stomach, brain and gill of kuruma shrimp. In lymphoid organ cells, an enhanced expression of both MjSTAT and MjSOCS genes are observed following stimulation with peptidoglycan and polycytidylic acid. These observations suggest that MjSTAT and MjSOCS might play a major role in the innate immune defense of kuruma shrimp. The discovery of JAK/STAT signaling pathway in shrimp will allow a complete and concrete understanding of shrimp cytokine signaling.

Deciphering the DNA repair protein, Rad23 from kuruma shrimp Marsupenaeus japonicus: full-length cDNA cloning and characterization

AIMS

 Lesions of DNA are removed by nucleotide excision repair (NER) process in the living systems. NER process-related host factors are believed to aid recovery steps during viral integration. Here, we report identification and characterization of a DNA repair molecule Rad23 from kuruma shrimp Marsupenaeus japonicus.

METHODS AND RESULTS

The full-length cDNA of M. japonicus Rad23 gene (MjRad23) has 1149 bp coding for a putative protein of 382 amino acids with a 5' untranslated region (UTR) of 92 bp and 3' UTR region of 1116 bp. Quantitative expression analysis revealed MjRad23 is constitutively expressed in all the organs of healthy shrimp, whereas with high level in muscle tissue. Although MjRad23 expression is observed in every haemolymph samplings to post-white spot syndrome virus infection, high expression is recorded at 2 h post infection (h.p.i.). MjRad23 consists of putative functional domains including one ubiquitin domain (UBQ), two ubiquitin-associated domains (UBA) and one heat-shock chaperonin-binding motif (STI1). Multiple alignment of MjRad23 with Rad23 of other species showed highly significant identity ranging from 37 to 53%; however, high homology is observed with Rad23 of Bombyx mori (BmRad23). UBQ domain region alignment revealed maximum of 66% homology with Rad23 of Apis melifera (AmRad23). MjRad23 clustered with invertebrate sector along with insect species in evolution analysis. Three-dimensional structural analyses demonstrated the highest identity between MjRad23 and human Rad23A (hHR23A).

CONCLUSIONS

The present work revealed the presence of MjRad23 gene, which is essential in DNA repair process. Further studies are required to clarify the involvement of MjRad23 in NER process.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report on identification and characterization of DNA repair protein in crustaceans, which will lead to further investigation to explore the molecular mechanisms behind the NER process.

Molecular cloning and transcriptional analysis of a newly identified anti-lipopolysaccharide factor gene in kuruma shrimp, Marsupenaeus japonicus

AIM

In the present study, we have cloned a new family of anti-lipopolysaccharide factor (ALF) from haemocytes of kuruma shrimp Marsupenaeus japonicus (MjALF2) using RACE method.

METHODS AND RESULTS

Transcriptional analysis of MjALF2 gene in the organs of healthy shrimp revealed prominent expression in gills and muscle. In vitro LPS stimulation in the lymphoid organ cells resulted in significant increase in expression at 48, 8 and 12 h poststimulation, compared to the nonstimulated cells. In vivo injection of V. penaeicida does not show any high expression in time course assay. Phylogenetic analysis showed MjALF2 is placed in the group closer to P. monodon isoform 1 and 2 than to MjALF1. The full-length MjALF2 gene consists of 558 bp with a 363 -bp open reading frame, encoding 121 amino acids. The deduced peptide contains a putative signal peptide of 22 amino acids with molecular mass of about 13.8 kDa molecular mass. The deduced amino acid sequence of MjALF2 showed 83.3 and 56.7% identity with ALF sequences of P. monodon.

CONCLUSIONS

The present work revealed the presence of MjALF2 gene, which is highly expressed in gills and muscle of healthy kuruma shrimp. Further studies are required to clarify the involvement of MjALF2 in immune responses for using as a therapeutic agent.

SIGNIFICANCE AND IMPACT OF THE STUDY

Antimicrobial peptides are promising potential therapeutic agents for disease control in aquaculture. Understanding the relation of MjALF2 with innate immunity mechanism will lead to develop better health management strategies for long-term sustainability of the shrimp industry.

A simple non-enzymatic method for the preparation of white spot syndrome virus (WSSV) DNA from the haemolymph of Marsupenaeus japonicus using FTA matrix cards

White spot syndrome virus (WSSV) is an important shrimp pathogen responsible for large economic losses for the shrimp culture industry worldwide. The nucleic acids of the virus must be adequately preserved and transported from the field to the laboratory before molecular diagnostic analysis is performed. Here, we developed a new method to isolate WSSV-DNA using Flinders Technology Associates filter paper (FTA matrix card; Whatman) without centrifugation or hazardous steps involved. FTA technology is a new method allowing the simple collection, shipment and archiving of nucleic acids from haemolymph samples providing DNA protection against nucleases, oxidation, UV damage, microbial and fungal attack. DNA samples prepared from 10-fold dilutions of moribund shrimp haemolymph using FTA matrix cards were analysed using semi-quantitative and quantitative polymerase chain reaction (PCR) and were compared with two commercially available DNA isolation methods, the blood GenomicPrep Mini Spin Kit (GE Healthcare) and the DNAzol (Invitrogen). Sequence analysis was performed for the DNA samples prepared using the various isolation procedures and no differences in the sequence among these methods were identified. Results based on the initial copy number of DNA prepared from the GenomicPrep Mini Spin Kit are a little more sensitive than the DNA prepared from FTA matrix cards, whereas the DNAzol method is not suitable for blood samples. Our data shows the efficiency of retention capacity of WSSV-DNA samples from impregnated FTA matrix cards. Matrix cards were easy to store and ship for long periods of time. They provide ease of handling and are a reliable alternative for sample collection and for molecular detection and characterization of WSSV isolates.

Real-time quantitative loop-mediated isothermal amplification as a simple method for detecting white spot syndrome virus

AIMS

White spot syndrome virus (WSSV) continues to be the most pathogenic virus among the crustacean aquaculture causing mass mortality. In the present study, we established a one-step, single tube, real-time accelerated loop-mediated isothermal amplification (real-time LAMP) for quantitative detection of WSSV.

MATERIALS AND METHODS

A set of six specially designed primers that recognize eight distinct sequences of the target. The whole process can be completed in 1 h under isothermal conditions at 63 degrees C. Detection and quantification can be achieved by real-time monitoring in an inexpensive turbidimeter based on threshold time required for turbidity in the LAMP reaction. A standard curve was constructed by plotting viral titre against the threshold time (T(t)) using plasmid standards with high correlation coefficient (R(2) = 0.988).

CONCLUSIONS

Sensitivity analysis using 10-fold dilutions (equivalent to 35 ng microl(-1) to 35 ag microl(-1)) of plasmid standards revealed this method is capable of detecting upto 100 copies of template DNA. Cross-reactivity analysis with DNA/cDNA of IHHNV, TSV, YHV-infected and healthy shrimp showed this method is highly specific for quantitative detection of WSSV.

SIGNIFICANCE AND IMPACT OF THE STUDY

WSSV real-time LAMP assay appears to be precise, accurate and a valuable tool for the detection and quantification of WSSV in large field samples and epidemiological studies.

Genetic and phenotypic comparison of Nocardia seriolae isolated from fish in Japan

The phenotypic and genetic characterizations of 58 isolates of the fish pathogen Nocardia seriolae, from amberjack, Seriolae dumerili, yellowtail, Seriola quinqueradiata, Japanese flounder, Paralichthys olivaceus, and chub mackerel, Scomber japonicus, in Japan from 1970-2005, were examined to investigate the epidemiological relationship between isolates. The phenotypic and genetic characterizations were determined by alpha-glucosidase activity and biased sinusoidal field gel electrophoresis (BSFGE) analysis, respectively. There was no alpha-glucosidase activity in strains isolated from 2000-05 (n = 50) with a few exceptions (n = 3), while all strains isolated from 1970-90 (n = 8) were positive. In BSFGE analysis, digestions with restriction enzymes Xba I and Ase I produced 15 and 16 restriction patterns, respectively. All restriction patterns obtained from 50 strains isolated during 2000-05 were unrelated to those obtained from eight strains isolated during 1970-90, with the exception of two strains isolated during recent outbreaks. Based on the phenotypic and genetic characterizations, recent outbreaks of nocardiosis in Japan are suggested to be epidemiologically unrelated to earlier outbreaks in Japan. Although a low genetic relationship was observed in the restriction pattern between recent and earlier isolates, identity was confirmed between these groups of isolates because five representative strains showed 99.9% homology with N. seriolae ATCC43993(T) in the 16S rRNA sequence.

Characterization of Lancefield group C Streptococcus dysgalactiae isolated from farmed fish

A Lancefield group C streptococcal (GCS) infection caused by Streptococcus dysgalactiae that is characterized by severe necrotic lesions of the caudal peduncle has been an increasing cause of mortality in farmed fish such as amberjack, Seriola dumerili, and yellowtail, Seriola quinqueradiata, in the southern part of Kyushu, Japan. In this study, enzymatic profiles of GCS strains from fish and mammals were investigated using the API ZYM system, and genotypic characterization of GCS strains was performed using biased sinusoidal field gel electrophoresis (BSFGE). The partial sequence of the 16S-23S rDNA intergenic spacer region of the GCS strain isolates from fish and mammals was also compared. The API ZYM test indicated that it is difficult to differentiate isolates of S. dysgalactiae from fish and animals based on enzymological variations. In the BSFGE analysis, the macrorestriction profiles, which were obtained using SmaI or ApaI as a restriction enzyme, revealed variations between the fish and animal isolates. The partial sequence of the 16S-23S rDNA intergenic spacer region of all the tested fish isolates differed from all mammalian isolates in one or two nucleotides. The possibility of a clonal expansion of S. dysgalactiae strains in farmed fish was also suggested by the BSFGE profiles of fish isolates.

Loop-mediated isothermal amplification: an emerging technology for detection of fish and shellfish pathogens

Fish and shellfish diseases are a constant threat to the sustainability and economic viability of aquaculture. Early diagnosis plays a vital role in management of fish and shellfish diseases. Traditionally, various biochemical and serological tests have been used for fish disease diagnosis. However, the time and expertise required for such diagnoses makes it difficult for aquaculturists to easily adopt them under production conditions. Polymerase chain reaction and probe-based nucleic acid detection have become increasingly popular in fish and shellfish diagnostics. Recently, a novel technique called loop-mediated isothermal amplification (LAMP) has been developed, which is highly sensitive and rapid. LAMP has been used for the detection of bacterial, viral, fungal and parasitic diseases in both animal and plants. In aquaculture, LAMP-based detection of pathogens like Edwardsiella tarda, E. ictaluri, Nocardia seriolae, Tetracapsuloides bryosalmonae, white spot syndrome virus and infectious haematopoietic necrosis virus have been reported. In this review, the application of LAMP for the detection of aquaculture-associated pathogens is discussed.

Lancefield group C Streptococcus dysgalactiae infection responsible for fish mortalities in Japan

A Lancefield serological group C Streptococcus sp. was isolated from cultured amberjack, Seriola dumerili Risso, and yellowtail, Seriola quinqueradiata Temminck and Schlegel, immunized with Lactococcus garvieae commercial vaccines in Japan. The isolated bacteria were Gram-positive cocci, auto-aggregating in saline, morphologically long chains in growth medium, catalase negative and alpha-haemolytic on blood agar. An almost complete gene sequence of the 16S rDNA of two isolates was determined and compared with that of bacterial strains in the database. The isolates were identified as Streptococcus dysgalactiae based on the results of the 16S rDNA sequence, the bacteriological properties and the Lancefield serological grouping. Oligonucleotide primers specifically designed for the 16S-23S rDNA intergenic spacer region of S. dysgalactiae amplified a gene from all the fish isolates, as well as the type strains alpha-haemolytic S. dysgalactiae subsp. dysgalactiae ATCC430738 and beta-haemolytic S. dysgalactiae subsp. equisimilis ATCC35666, but not those of S. equi ATCC33398, Lactococcus garvieae ATCC43921 and L. garvieae KG9408. The severe necrotic lesions of the caudal peduncle seen in experimentally infected fish were similar to those seen in naturally infected fish.

Improved conception in timed-artificial insemination using a progesterone-releasing intravaginal device and Ovsynch protocol in postpartum suckled Japanese Black beef cows

The primary objective was to determine the effect of supplemental progesterone, administered via an intravaginal device (CIDR), on conception rates to timed-artificial insemination (timed-AI) in postpartum suckled Japanese Black beef cows treated with the Ovsynch protocol. A secondary objective was to compare the effects of treatments on plasma concentrations of progesterone and estradiol. Cows in the control group (Ovsynch, n=38) received a standard Ovsynch protocol (100 microg GnRH analogue on Day 0, 500 microg PGF2alpha analogue on Day 7, and 100 microg GnRH analogue on Day 9), with AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the treatment group (Ovsynch+CIDR; n=40) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Plasma progesterone concentrations were determined on Days 0, 1, 7, 9, 10, and 17 and plasma estradiol-17beta concentrations were determined on Days 7, 9, 10, and 17. The odds ratio for likelihood of conception was 3.29 times greater (P=0.02) in the Ovsynch+CIDR group compared to Ovsynch group. The conception rate was greater (P=0.03) in the Ovsynch+CIDR group than in the Ovsynch group (72.5% versus 47.7%). Insertion of a CIDR device significantly increased plasma progesterone concentrations only on Days 1 and 7 (P<0.001 and P=0.05, respectively), but had no significant effect on plasma estradiol-17beta concentrations. Including a CIDR with the Ovsynch protocol significantly improved conception rates in postpartum suckled Japanese Black beef cows.

Red swamp crawfish (Procambarus clarkii): an alternative experimental host in the study of white spot syndrome virus

The pathogenicity of white spot syndrome virus (WSSV) for the red swamp crawfish (Procambarus clarkii) was investigated after infection by intramuscular (i.m.) injection and oral route. The cumulative mortality of crawfish injected i.m. with WSSV reached 100% in 5 days. After oral feeding WSSV-infected kuruma shrimp (Penaeus japonicus) muscle tissues to the crawfish the cumulative mortality of this host reached 100% in 11 days. On reinfection trials, all the crawfish fed WSSV-infected crawfish muscle tissues died in 9 days. All the shrimp injected with a filtrate of infected crawfish heart tissues died in 12 days with typical signs of white spot syndrome (WSS). Electron microscopy clearly demonstrated that WSSV propagated in the cells of the crawfish midgut. This study showed that the red swamp crawfish can be used as alternative experimental host in the study of WSSV.

Primary culture of lymphoid organ cells and haemocytes of kuruma shrimp, Penaeus japonicus

A primary cell culture system was developed for the cells of lymphoid organ tissue of kuruma shrimp, Penaeus japonicus. Minced tissues of lymphoid organs were seeded and incubated at 30 degrees C in medium 199 supplemented with 20% foetal bovine serum, a salt mixture and a lactalbumin hydrolysate (0.1 g/l). Fibroblast-like cells and epithelioid-like cells survived for 54 days. Cells did not survive after trypsin, collagenase or hyaluronidase treatment used for cell dissociation. Mitogens (Con A, PHA-P, Pokeweed) and insulin did not enhance cell proliferation. When penaeid rod-shaped DNA virus (PRDV) was inoculated into the lymphoid organ cell culture, a cytopathic effect was observed within 8 days. On the other hand, large granular haemocytes that were fractionated using a Percoll continuous density gradient were not infected with PRDV in vitro within 10 days, which was the longest period of haemocyte maintenance.

Teratogenic evaluation of di-n-butyl phthalate in rats

Pregnant rats were given di-n-butyl phthalate (DBP) by gastric intubation at a dose of 0, 0.5, 0.63, 0.75 or 1.0 g/kg on days 7-15 of pregnancy. A significant decrease in the maternal body weight gain after treatment with DBP was found at a dose of 0.63 g/kg and above. Maternal death and complete resorption of implanted embryos in all the surviving dams were observed in the 1.0 g/kg group. Significantly increased incidence of postimplantation loss and decreased fetal weight were detected at doses of 0.63 and 0.75 g/kg. The incidence of fetuses with malformations was higher in the 0.63 and 0.75 g/kg groups than in the control group, and the difference was significant in the 0.75 g/kg group. Cleft palate were predominantly observed.

Teratogenic phase specificity of butyl benzyl phthalate in rats

Pregnant rats were given butyl benzyl phthalate (BBP) by gastric intubation at a dose of 0.6, 0.75 or 1.0 g/kg on days 7-9, 10-12 or 13-15 of pregnancy. While treatment with BBP on days 7-9 or 13-15 at doses of 0.75 and 1.0 g/kg was significantly teratogenic, no evidence of teratogenicity was detected when BBP was given on days 10-12. The incidence of malformed fetuses was proportional to the dose of BBP. Treatment on days 7-9 with BBP at doses of 0.75 g/kg and above caused a significant increase in the number of skeletal malformations, such as fusion of the cervical vertebral arches and deformity of the thoracic vertebrae, but neither external nor internal malformations. Treatment on days 13-15 with two higher doses of BBP resulted in a significantly increased incidence of fetuses with external and skeletal malformations such as cleft palate and fusion of the sternebrae. The highest incidence of malformed fetuses occurred after treatment with BBP on days 13-15. It could be concluded that the susceptibility to the teratogenicity of BBP varies with the developmental stage at the time of administration.

Teratogenic evaluation of p-tert-butylphenol formaldehyde resin (novolak type) in rats following oral exposure

The teratogenicity of p-tert-butylphenol formaldehyde resin, novolak type, (PTBP-FR) was examined in Wistar rats. Pregnant rats were fed diets containing 0, 2.5, 5 or 10% of PTBP-FR ad libitum from day 6 to day 15 of pregnancy. Maternal toxicity, as evidenced by a decreased maternal body weight gain and food consumption, was observed in the 5 and 10% dose groups. However, treatment-related clinical signs were not observed. No significant reductions in the fetal body or placental weights were observed in any dose group. There were no significant differences in the number of live fetuses, intrauterine deaths (dead fetuses and resorptions), or fetal sex ratios found between the PTBP-FR-treated and control groups. Although external and internal malformations including short tail, dilatation of the cerebral ventricle and the renal pelvis and dextrocardia, and some skeletal variations were observed in fetuses at some groups treated with PTBP-FR, the incidences of these morphological alterations were not statistically different from controls. In conclusion, PTBP-FR administered orally to Wistar rats during days 6-15 of gestation produced no related signs of developmental toxicity.

Teratological assessment of glutaraldehyde in rats by gastric intubation

Pregnant rats were given glutaraldehyde (GA) by gastric intubation at a dose of 0, 25, 50 or 100 mg/kg on days 6-15 of pregnancy. Maternal toxicity occurred in the 100 mg/kg group as evidenced by a significant increase in maternal death and a significant decrease in maternal body weight gain and food consumption. A significantly lowered fetal weight was also found in the 100 mg/kg group. No significant change induced by GA was detected in the incidence of postimplantation loss. Morphologic examinations of fetuses revealed no evidence of teratogenicity of GA. It could be concluded that GA has no teratogenic effects on rat offspring even at a dose which induced severe maternal toxicity.

Teratological assessment of diiodomethyl p-tolyl sulfone in rats

Pregnant rats were given diiodomethyl p-tolyl sulfone (DIMPTS) at a dose of 0, 0.125, 0.25, 0.5 or 1.0% in the diet on days 6-15 of pregnancy. Maternal body weight gain and food consumption during the administration period were significantly lowered in the 0.25, 0.5 and 1.0% groups. No significant changes induced by DIMPTS were detected in the number of resorptions and dead fetuses, and body weight of live fetuses. Morphological examinations of fetuses revealed no evidence of teratogenesis. It could be concluded that DIMPTS has no teratogenic effects on rat offspring, even at doses which induced maternal toxicity.

Teratogenic evaluation of butyl benzyl phthalate in rats by gastric intubation

Pregnant rats were given butyl benzyl phthalate (BBP) by gastric intubation at a dose of 0, 0.5, 0.75 or 1.0 g/kg on days 7-15 of pregnancy. In the 0.5 g/kg group, food consumption during the administration period was significantly decreased, but no adverse effect on the embryo-fetus was detected. High maternal lethality and complete resorption of implanted embryos in all the surviving dams were observed in the 1.0 g/kg group. Increased embryo-fetal death and decreased fetal weight were found at a dose of 0.75 g/kg which also caused reductions in maternal body weight gain and food consumption. A significantly and markedly increased incidence of fetal malformations was also detected in the 0.75 g/kg group. Cleft palate, fusion of the sternebrae and dilatation of the renal pelvis were mostly observed.

Embryolethality and teratogenicity of butyl benzyl phthalate in rats

Pregnant Wistar rats were given butyl benzyl phthalate (BBP) at a dose of 2.0% in the diet on days 0-20, days 0-11 or days 11-20 of pregnancy. Food consumption and body weight gain were decreased in pregnant rats given BBP. Pre-implantation loss in the BBP-treated groups was comparable to that in the control and pair-fed groups. All dams given BBP on days 0-20 or days 0-11 exhibited complete resorption of all the implanted embryos. No increase in post-implantation loss was found in pregnant rats given BBP on days 11-20. Marked teratogenicity was detected in fetuses of the dams given BBP on days 11-20. Cleft palate and fusion of the sternebrae were predominantly observed. Seventy-two of the 134 fetuses had a cleft palate. The incidence of malformations in this group was significantly and markedly higher than that in the control and pair-fed groups. In conclusion, the administration of BBP during the first and second half of pregnancy produced embryolethality and teratogenicity, respectively.

[Antipyretic effects of traditional Chinese medicines in bacterial endotoxin-induced febrile rabbits]

The antipyretic effects of oral administration of eight traditional Chinese medicines (dried extracts) were tested in febrile rabbits injected with bacterial pyrogen, lipopolysaccharide (LPS) 0.05 micrograms/kg (i.v.). The traditional Chinese medicines were given 0.6-2 g/10 ml/kg (p.o.) simultaneously with LPS. The most potent antipyretic effect was observed in Dai-jyoki-to (Ta-chen-chi-tang). The moderate antipyretic effects were observed in Toki-syakuyaku-san (Tang-kuei-shao-yao-san) and Syo-saiko-to (Hssiao-chai-hu-tang). Koso-san (Hsiang-su-san), Oren-gedoku-to (Huang-lien-chieh-tu-tan), Gorei-san (Wu-ling-san), Kakkon-to (Ko-ken-tang) and Byakkoka-ninjin-to (Pai-hu-chia-jen-sheng-tang) showed no effects.

Effect of period of exposure on the developmental toxicity of butyl benzyl phthalate in rats

The objective of the present study was to determine if periods of exposure would modify the developmental toxicity of butyl benzyl phthalate (BBP). Pregnant Wistar rats were given BBP at a dose of 2.0% in the diet on days 0-20, days 0-7, days 7-16 or days 16-20 of pregnancy. Food consumption and body weight gain were decreased in the pregnant rats given BBP. All dams given BBP on days 0-20 exhibited complete resorption of all the implanted embryos. Post-implantation loss in the pregnant rats given BBP on days 0-7 or 7-16 was higher than that in the control and pair-fed pregnant rats. No increase in post-implantation loss was found in the pregnant rats given BBP on days 16-20. Pre-implantation loss in the BBP-treated groups was comparable to the control and pair-fed groups. Striking teratogenicity was detected in fetuses of the dams given BBP on days 7-16. Cleft palate and fusion of the sternebrae were predominantly observed. About 95% of the fetuses in this group had cleft palate. The incidence of malformations in this group was significantly and markedly higher than that in the control and pair-fed groups.

Susceptible period for the teratogenicity of di-n-butyltin dichloride in rats

Pregnant rats were given di-n-butyltin dichloride (DBT) by gastric intubation at a dose of 20 mg/kg on days 7-9, 10-12 or 13-15 of pregnancy or at a dose of 20 or 40 mg/kg on day 6, 7, 8 or 9 of pregnancy. While treatment with DBT on days 7-9 was significantly and highly teratogenic, no evidence of teratogenicity was detected when DBT was given on days 10-12 or 13-15. Treatment on day 7 or 8 with both doses of DBT, but neither on day 6 or 9, resulted in an increased incidence of fetuses with malformations. The highest incidence of malformed fetuses occurred after treatment on day 8. The incidence of malformed fetuses was proportional to the dose of DBT. Anomaly of tail, anal atresia, club foot, omphalocele, deformity of the vertebral column, defect of the ribs and anophthalmia or microphthalmia were predominantly observed. It could be concluded that, following maternal exposure to DBT in rats, developing offspring are not susceptible to teratogenic effects of DBT on day 6 and that day 7 is the earliest susceptible period, day 8 is the highest susceptible period and day 9 is no longer a susceptible period for teratogenesis of DBT.

Teratogenicity of di-n-butyltin dichloride in rats

Pregnant rats were given di-n-butyltin dichloride (DBT) by gastric intubation at a dose of 0, 2.5, 5.0, 7.5 or 10.0 mg/kg on days 7-15 of pregnancy. Maternal toxicity occurred in the 7.5 and 10.0 mg/kg groups as evidenced by a significant increase in maternal death and decrease in food consumption and body weight gain. The incidence of fetuses with malformations was roughly proportional to the dose of DBT, and was significantly increased in the 5.0, 7.5 and 10.0 mg/kg groups. Cleft jaw, ankyloglossia, defects of the mandible, fusion of the ribs and deformity of the vertebral column were predominantly found. It is concluded that DBT produced teratogenic effects in the absence of maternal toxicity.

Behavioral effects of acute exposure to tributyltin chloride in rats

The behavioral effects of a single acute exposure to nonlethal doses of tributyltin chloride (TBTCl) were studied in male Wistar rats. The rats were given TBTCl by oral gavage at doses of 0, 6.3, 12.5, 25.0 or 50.0 mg/kg, and spontaneous motor activity (SMA) and acquisition of conditioned avoidance responses in a shuttle box were monitored. Body weight gain in the 50.0-mg/kg group was significantly lowered, but weight gain in the 6.3-, 12.5- and 25.0-mg/kg groups was comparable to that in the control group. TBTCl caused a dose-related decrease in SMA during the dark phase. The 24-h total daily and 12-h nocturnal activity was decreased at doses of 12.5 mg/kg and above. The acquisition of shock avoidance responses was inhibited in all TBTCl-treated groups in a dose-dependent manner, and the difference was significant for rats given TBTCl at doses of 25.0 mg/kg and above. The data indicate that an acute exposure to TBTCl can cause significant changes in rat behavior and suggest that SMA can serve as a sensitive index for detecting its toxicity.

Simple determination of tin in biological materials by atomic absorption spectrometry with a graphite furnace

A simple and rapid determination of tin in biological materials (blood, brain, liver, kidney, etc,) by atomic absorption spectrometry (AAS) with a graphite furnace is described. Suppression of interferences by direct addition of ascorbic acid in wet-ashed biological materials was investigated for the determination of tin. This method involves no extraction with organic solvent for removal of the interferences, and therefore it is neither time consuming nor error prone, and is suitable for large sample sizes and small sample volumes. The limit of detection of this method is 0.002 microgram/mL, equivalent to a limit of detection in the materials of 0.02 microgram/g. The calibration graph is linear up to 1 microgram/mL of tin.

Evaluation of the embryolethality of butyl benzyl phthalate by conventional and pair-feeding studies in rats

The embryolethality of butyl benzyl phthalate (BBP) was studied in Wistar rats. Pregnant rats were given BBP at dosages of 0 (control) and 2.0% in the diet from day 0 to day 20 of pregnancy. Daily intake of BBP was 974 mg kg-1 for the 2.0% BBP group. In this group, all dams exhibited complete resorption of all the implanted embryos, and their food consumption, body weight gain and adjusted weight gain (body weight gain excluding the gravid uterus) during pregnancy were markedly lowered. To determine whether the embryolethality was the result of reduced food-consumption during pregnancy, a pair-feeding study was performed in which the pregnant rats received the same amount of diet consumed by the 2.0% BBP-treated pregnant rats. The pair-fed and 2.0% BBP-treated pregnant rats showed significant and comparable reductions in the adjusted weight gain. In the pair-fed group, the incidences of postimplantation and total losses were higher than those in the control group, and the number of live fetuses per litter was lower than the control value. However, the complete resorption of all the implanted embryos was not found in any of the pair-fed pregnant rats. It could be concluded that the embryolethality observed in the 2.0% BBP-treated pregnant rats is attributable to the effects of dietary BBP but not to the maternal malnutrition from reduced food consumption during pregnancy.

Changes of spontaneous motor activity of rats after acute exposure to tributyltin chloride

The effects of a single acute exposure to tributyltin chloride (TBTCl) on spontaneous motor activity (SMA) in home cage were studied in male Wistar rats. The rats were given TBTCl intraperitoneally at a dosage of 0, 1.6 or 3.3 mg/kg, and the SMA was measured for five days after administration of TBTCl. Body weight gain in the 3.3 mg/kg group was significantly lowered, but that in the 1.6 mg/kg group was comparable to that in the control group. The SMA during light phase was not affected by TBTCl treatment. However, the SMA during dark phase was decreased in both of the TBTCl-treated groups. These decreases in SMA gradually returned to the control levels. The 24-hr total daily and 12-hr nocturnal activity in the TBTCl-treated groups were decreased in a dose-dependent manner. These data indicate that TBTCl possesses behavioral toxicity and suggest that the decreased nocturnal SMA is a sensitive index for detecting toxicity of chemicals in rats.

Evaluation of the teratogenic potential of the plasticizer butyl benzyl phthalate in rats

The teratogenicity of butyl benzyl phthalate (BBP) was studied in Wistar rats. Pregnant rats were given BBP at a dosage of 0, 0.25, 0.5, 1.0 or 2.0% in the diet from day 0 to day 20 of pregnancy. Daily intakes of BBP were 185 mg kg-1 for the 0.25% group, 375 mg kg-1 for the 0.5% group, 654 mg kg-1 for the 1.0% group and 974 mg kg-1 for the 2.0% group. Adjusted maternal body weight gain (body weight gain excluding the gravid uterus) during pregnancy in the 1.0 and 2.0% groups was significantly lowered. Food consumption during pregnancy in the 0.25 and 0.5% groups did not differ from that in the control group. No death was noted in the pregnant females of any group. There was no significant compound-related effects on the incidence of preimplantation loss. All dams given 2.0% BBP exhibited complete resorption of all the implanted embryos. Morphological examinations of the fetuses revealed no evidence of teratogenesis. It could be concluded that the no-observable-effect-levels (NOEL) in rats were 0.5 and 1.0% BBP in the diet for maternal and embryofetal toxicity, respectively.

[National Institute of Hygienic Sciences Standard (the Japanese Pharmacopoeia Standard) "Endotoxin Reference Standard" (Control 891)]

The second "Endotoxin Reference Standard" (Control 891) of the National Hygienic Sciences (Japanese Pharmacopoeia Standard) was prepared. As a result of the test of its potency against the preceding lot of the Reference Standard (Control 881), the second "Endotoxin Reference Standard" (Control 891) containing 16000 endotoxin units per vial was authorized.

Teratogenic evaluation of tributyltin chloride in rats following oral exposure

The teratogenicity of tri-n-butyltin chloride (TBTC1) was examined in Wistar rats. The pregnant rats were administered orally 25, 15, 9, 5 and 0(Control) mg of TBTC1/kg of body weight/day from day 7 to 15 of pregnancy. Maternal toxicity, as evidenced by both of decreased body weight gain and food consumption was observed at 25, 15 and 9 mg/kg/day dose group. However, only in the 25 mg/kg/day dose group some clinical signs of toxicity (sedation, diarrhoea and salivation) were observed and 70 percent of the dams were dead. In the 25 mg/kg/day dose group, all fetuses were dead. Statistically significant reductions in the female fetal body weight were observed in 9 and 5 mg/kg/day dose groups. In all groups treated with TBTC1 except the 25 mg/kg/day dose group, no significant differences in the numbers of live fetuses and intrauterine death (dead fetuses and resorptions) or sex ratios of fetuses were found between the TBTC1-treated and control groups. Fetal external, skeletal and internal malformations were not observed at any of the dose levels. However, several types of skeletal and internal variations including delayed ossifications were observed in some groups treated with TBTC1, but the incidences were not significantly different from controls. Also, two fetuses with dilatation of the renal pelvis were found in 9 and 5 mg/kg/day dose group. Statistically significant increases of placental weight in all TBTC1-treated groups were observed when compared to that of control group. In conclusion, TBTC1 administered orally to Wistar rats during days 7-15 of pregnancy produced related signs of fetal toxicity but no evidence of teratogenicity and induced a marked increase in placental weight.

Evaluation of teratogenic potential of sodium sulfite in rats

The teratogenicity of sodium sulfite was examined in Wistar rats. The pregnant rats were fed diets containing 5, 2.5, 1.25, 0.63 or 0.32% of sodium sulfite heptahydrate(Na2SO3.7H2O) ad libitum from day 8 to 20 of pregnancy. Maternal toxicity, as evidenced by decreased body weight gain and decreased food consumption was observed at the 5% group, but no clinical signs of toxicity were observed. A significant reduction in the fetal body weight of both sexes was observed in all dose groups except 2.5% group. No significant differences in the numbers of live fetuses and intrauterine death (dead fetuses and resorptions) or sex ratios of fetuses were found between the sodium sulfite-treated and control groups. Fetal external, skeletal and internal malformations were not observed at any dose level. However, several types of skeletal and internal variations as well as delayed ossifications were observed in some groups treated with sodium sulfite, but the incidences were not significantly different from controls. Also, some fetuses with dilatation of the renal pelvis and the lateral ventricle were found in all groups except 1.25% group, but there was no dose-response. The live birth index and survival rate of offspring within 4 weeks and their body weight gain at 3 weeks after birth were not affected by sodium sulfite-treatment. In conclusion, sodium sulfite (0, 0.32, 0.63, 1.25, 2.5 or 5.0% as Na2SO3.7H2O) administered in the diet to Wistar rats during days 8-20 of pregnancy produced related signs of fetal toxicity but no evidence of teratogenicity.

Evaluation of the teratogenic potential of the rubber accelerator N-cyclohexyl-2-benzothiazylsulfenamide in rats

The teratogenicity of N-cyclohexyl-2-benzothiazylsulfenamide (CBS) was studied in Wistar rats. Pregnant rats were given CBS at a dosage of 0.001, 0.01, 0.1 or 0.5% in the diet from Day 0 to Day 20 of pregnancy. Daily intakes of CBS were 0.7 mg kg-1 for the 0.001% group, 7.1 mg kg-1 for the 0.01% group, 69.6 mg kg-1 for the 0.1% group and 288.8 mg kg-1 for the 0.5% group. Maternal body weight gain during pregnancy in the 0.1 and 0.5% groups was significantly lowered. Food consumption during pregnancy in the CBS-treated groups, except for the 0.5% group, did not differ from that in the control group. Neither death nor clinical signs of toxicity were noted in the pregnant females of any group. Lowered weight in fetuses and the placentae were observed in the 0.5% group. There were no significant compound-related effects on the incidences of pre- and post-implantation losses and the number and ratio of live fetuses. Morphological examinations of the fetuses revealed no evidence of teratogenesis. It could be concluded that CBS possesses no adverse effects on the prenatal development of the offspring in rats at doses employed in the present study.

Dolichol kinase in rat sarcoplasmic reticulum membrane preparations

A dolichol kinase (EC 2.7.1.108) was found in sarcoplasmic reticulum membrane fractions from rat leg muscle. This enzyme specifically required CTP as a phosphoryl donor and relatively little activity was found in the absence of exogenous detergent-suspended dolichol. Unlike other reported dolichol kinases, the kinase from skeletal muscle was activated almost equally well by Ca2+, Zn2+, or Mg2+, but not Mn2+. No effect of calmodulin was seen. The kinase exhibited a single pH optimum at pH 7-8 in contrast to kinases from certain other tissues. Despite the low level of dolichol present in skeletal muscle, the kinase in the sarcoplasmic reticulum fraction had an activity comparable to that of microsomal preparations from tissues such as brain and liver, which may indicate that skeletal muscle has a high capacity for dolichol phosphorylation and protein glycosylation.

Teratology study of diethylene glycol mono-n-butyl ether in rats

The teratogenicity of diethylene glycol mono-n-butyl ether (DEGMBE) was studied in Wistar rats. The pregnant rats were fed a diet containing DEGMBE from day 0 through day 20 of pregnancy. The dietary concentrations of DEGMBE were 0, 0.04, 0.2 and 1% and the daily intakes of DEGMBE were 0, 25, 115 and 633 mg/kg, respectively. In the DEGMBE-treated groups, the maternal body weight gain during pregnancy was significantly reduced, but neither decrease in food consumption during pregnancy nor any clinical sign of toxicity was observed. No significant differences between the DEGMBE-treated groups and the control group were found in the pre- and postimplantation losses, the number of live fetuses per litter, the sex ratio of live fetuses, the fetal body weight and the placental weight. External, skeletal and internal examinations of the fetuses revealed no evidence of teratogenesis. In the postnatal development of the offspring from the dams given DEGMBE, a high survival rate and good growth of the offspring were noted. It could be concluded that DEGMBE has no adverse effects on the pre- and postnatal development of the offspring in rats.

Teratology study of Tween 60 in rats

The teratogenicity of Tween 60 was studied in Wistar rats. Pregnant rats were given Tween 60 at a dose of 0, 0.1, 1.0 or 10% in the diet from day 7 to day 14 of pregnancy. Daily intakes of Tween 60 were 99 mg/kg for the 0.1% group, 960 mg/kg for the 1.0% group and 7693 mg/kg for the 10% group. No change induced by Tween 60 was detected in the number, sex ratio and body weight of live fetuses. External, skeletal and internal examinations of the fetuses revealed no evidence of teratogenesis. It could be concluded that Tween 60 has no harmful effects on the prenatal development of the rat offspring at doses employed in the present study.

[A cylindrical thermistor probe for experiments on suppositories in rabbits]

A cylindrical thermistor probe with a rubber disk stopper, which is beneficial for inserting a suppository into the rectum of rabbits without removal of the probe from the rectum, was developed. It is possible to measure body temperature continuously by using this probe in an experiment to assess the effects of a suppository on the body temperature of rabbits. After insertion of a suppository, leakage of the melted suppository from the rectum was not observed. No differences between this thermistor probe and an ordinary thermistor probe in the ability of the probe to detect the febrile response of rabbits injected with a bacterial pyrogen were observed. From these results, it could be concluded that this newly improved cylindrical thermistor probe is suitable for studying the effect of suppositories on the body temperature of rabbits.