Hepatocellular carcinoma tumour burden score to stratify prognosis after resection

BACKGROUND

Although the Barcelona Clinic Liver Cancer (BCLC) staging system has been largely adopted in clinical practice, recent studies have emphasized the need for further refinement and subclassification of this system.

METHODS

Patients who underwent hepatectomy with curative intent for BCLC-0, -A or -B hepatocellular carcinoma (HCC) between 2000 and 2017 were identified using a multi-institutional database. The tumour burden score (TBS) was calculated, and overall survival (OS) was examined in relation to TBS and BCLC stage.

RESULTS

Among 1053 patients, 63 (6·0 per cent) had BCLC-0, 826 (78·4 per cent) BCLC-A and 164 (15·6 per cent) had BCLC-B HCC. OS worsened incrementally with higher TBS (5-year OS 77·9, 61 and 39 per cent for low, medium and high TBS respectively; P < 0·001). No differences in OS were noted among patients with similar TBS, irrespective of BCLC stage (61·6 versus 58·9 per cent for BCLC-A/medium TBS versus BCLC-B/medium TBS, P = 0·930; 45 versus 13 per cent for BCLC-A/high TBS versus BCLC-B/high TBS, P = 0·175). Patients with BCLC-B HCC and a medium TBS had better OS than those with BCLC-A disease and a high TBS (58·9 versus 45 per cent; P = 0·005). On multivariable analysis, TBS remained associated with OS among patients with BCLC-A (medium TBS: hazard ratio (HR) 2·07, 95 per cent c.i. 1·42 to 3·02, P < 0·001; high TBS: HR 4·05, 2·40 to 6·82, P < 0·001) and BCLC-B (high TBS: HR 3·85, 2·03 to 7·30; P < 0·001) HCC. TBS could also stratify prognosis among patients in an external validation cohort (5-year OS 79, 51·2 and 28 per cent for low, medium and high TBS respectively; P = 0·010).

CONCLUSION

The prognosis of patients with HCC varied according to the BCLC stage but was largely dependent on the TBS.

The fate of W chromosomes in hybrids between wild silkmoths, Samia cynthia ssp.: no role in sex determination and reproduction

Moths and butterflies (Lepidoptera) have sex chromosome systems with female heterogamety (WZ/ZZ or derived variants). The maternally inherited W chromosome is known to determine female sex in the silkworm, Bombyx mori. However, little is known about the role of W chromosome in other lepidopteran species. Here we describe two forms of the W chromosome, W and neo-W, that are transmitted to both sexes in offspring of hybrids from reciprocal crosses between subspecies of wild silkmoths, Samia cynthia. We performed crosses between S. c. pryeri (2n=28, WZ/ZZ) and S. c. walkeri (2n=26, neo-Wneo-Z/neo-Zneo-Z) and examined fitness and sex chromosome constitution in their hybrids. The F1 hybrids of both reciprocal crosses had reduced fertility. Fluorescence in situ hybridization revealed not only the expected sex chromosome constitutions in the backcross and F2 hybrids of both sexes but also females without the W (or neo-W) chromosome and males carrying the W (or neo-W) chromosome. Furthermore, crosses between the F2 hybrids revealed no association between the presence or absence of W (or neo-W) chromosome and variations in the hatchability of their eggs. Our results clearly suggest that the W (or neo-W) chromosome of S. cynthia ssp. plays no role in sex determination and reproduction, and thus does not contribute to the formation of reproductive barriers between different subspecies.

Suppression of in vitro proliferative scar fibroblast contraction by interferon alfa-2b

Increased fibroblast activity and collagen production have been observed frequently in proliferative scars. Previous studies have demonstrated that interferons suppress collagen production by means of normal, keloid, and hypertrophic scar-derived fibroblasts. The fibroblast-populated collagen lattice is an in vitro model used to study fibroblast function. We used fibroblast-populated collagen lattices to evaluate the effect of interferon on fibroblasts harvested from normal human skin, human keloid, and hypertrophic scar tissues. Human recombinant interferon alfa-2b (1000 IU/ml) was added to the culture media. The collagen gel, prepared from rat tail tendon bundles, was overlaid with 5 x 10(4) fibroblast cells. Keloid fibroblast-populated collagen lattices showed the highest contraction. Contraction in all the groups appeared suppressed by interferon alfa-2b during the first 72 hours of study (p < 0.05). The reduction in fibroblast-populated collagen lattice contraction by interferon alfa-2b was similar among the groups. The contractile properties of fibroblasts taken from normal human skin, keloids, and hypertrophic scars in this in vitro study were suppressed by interferon alfa-2b. This suggested that interferon alfa-2b may be beneficial for the treatment of proliferative scars.

Step-by-step evolution of neo-sex chromosomes in geographical populations of wild silkmoths, Samia cynthia ssp

Geographical subspecies of wild silkmoths, Samia cynthia ssp. (Lepidoptera: Saturniidae), differ considerably in sex chromosome constitution owing to sex chromosome fusions with autosomes, which leads to variation in chromosome numbers. We cloned S. cynthia orthologues of 16 Bombyx mori genes and mapped them to chromosome spreads of S. cynthia subspecies by fluorescence in situ hybridization (FISH) to determine the origin of S. cynthia neo-sex chromosomes. FISH mapping revealed that the Z chromosome and chromosome 12 of B. mori correspond to the Z chromosome and an autosome (A₁) of S. c. ricini (Vietnam population, 2n=27, Z0 in female moths), respectively. B. mori chromosome 11 corresponds partly to another autosome (A₂) and partly to a chromosome carrying nucleolar organizer region (NOR) of this subspecies. The NOR chromosome of S. c. ricini is also partly homologous to B. mori chromosome 24. Furthermore, our results revealed that two A₁ homologues each fused with the W and Z chromosomes in a common ancestor of both Japanese subspecies S. c. walkeri (Sapporo population, 2n=26, neo-Wneo-Z) and S. cynthia subsp. indet. (Nagano population, 2n=25, neo-WZ₁Z₂). One homologue, corresponding to the A₂ autosome in S. c. ricini and S. c. walkeri, fused with the W chromosome in S. cynthia subsp. indet. Consequently, the other homologue became a Z₂ chromosome. These results clearly showed a step-by-step evolution of the neo-sex chromosomes by repeated autosome-sex chromosome fusions. We suggest that the rearrangements of sex chromosomes may facilitate divergence of S. cynthia subspecies towards speciation.

Ecdysone response element in a baculovirus immediate-early gene, ie1, promoter

A computer-assisted analysis identified tentative target sequences for regulatory proteins including ecdysone-inducible factors such as BmFTZ-F1 and Broad-Complex Z4 (BR-C Z4) in the ie1 promoter of BmNPV. A transient expression experiment using BmN cells and a series of truncated ie1 promoter constructs demonstrated that the activity of the ie1 promoter responded to alpha-ecdysone and 20-hydroxyecdysone, which required a tridecameric nucleotide stretch (ie1EcRE, 5'-GTGTTATCGACCT-3') homologous to the ecdysone response element reported for Drosophila (DmEcRE). RT-PCR demonstrated the expression of BmEcR and BmUSP, which are required as ecdysone-specific activators for EcRE-mediated activation, in BmN cells. Furthermore, the ie1 EcRE-mediated response was confirmed by using a recombinant BmNPV possessing a luciferase gene under the control of the ie1 promoter with or without ie1 EcRE. This is the first report of an ecdysone response element in a baculoviral gene promoter. These results also suggested that the regulation of the ie1 by ecdysone may militate viral replication at least under certain conditions during natural infections in vivo.

Partial deletions of the W chromosome due to reciprocal translocation in the silkworm Bombyx mori

In the silkworm, Bombyx mori (female, ZW; male, ZZ), femaleness is determined by the presence of a single W chromosome, irrespective of the number of autosomes or Z chromosomes. The W chromosome is devoid of functional genes, except the putative female-determining gene (Fem). However, there are strains in which chromosomal fragments containing autosomal markers have been translocated on to W. In this study, we analysed the W chromosomal regions of the Zebra-W strain (T(W;3)Ze chromosome) and the Black-egg-W strain (T(W;10)+(w-2) chromosome) at the molecular level. Initially, we undertook a project to identify W-specific RAPD markers, in addition to the three already established W-specific RAPD markers (W-Kabuki, W-Samurai and W-Kamikaze). Following the screening of 3648 arbitrary 10-mer primers, we obtained nine W-specific RAPD marker sequences (W-Bonsai, W-Mikan, W-Musashi, W-Rikishi, W-Sakura, W-Sasuke, W-Yukemuri-L, W-Yukemuri-S and BMC1-Kabuki), almost all of which contained the border regions of retrotransposons, namely portions of nested retrotransposons. We confirmed the presence of eleven out of twelve W-specific RAPD markers in the normal W chromosomes of twenty-five silkworm strains maintained in Japan. These results indicate that the W chromosomes of the strains in Japan are almost identical in type. The Zebra-W strain (T(W;3)Ze chromosome) lacked the W-Samurai and W-Mikan RAPD markers and the Black-egg-W strain (T(W;10)+(w-2) chromosome) lacked the W-Mikan RAPD marker. These results strongly indicate that the regions containing the W-Samurai and W-Mikan RAPD markers or the W-Mikan RAPD marker were deleted in the T(W;3)Ze and T(W;10)+(w-2) chromosomes, respectively, due to reciprocal translocation between the W chromosome and the autosome. This deletion apparently does not affect the expression of Fem; therefore, this deleted region of the W chromosome does not contain the putative Fem gene.

Use of RNAi technology to confer enhanced resistance to BmNPV on transgenic silkworms

dsRNA is a powerful tool for gene-specific silencing in plants and animals. In this study, we examined the use of gene silencing in generating transgenic silkworms resistant to the Bombyx mori nucleopolyhedrovirus (BmNPV). Using a transposon piggyBac system, we first generated BmN cells (rBmN-lef1), which carried artificial genes designed for expressing dsRNAs with sequences of the essential viral gene lef-1. NPV DNA microarray analysis revealed that the accumulation of lef-1 mRNA was successfully inhibited in rBmN-lef1 infected with BmNPV. The virus titer in the culture medium of rBmN-lef1 at 48 hr post-infection (h.p.i.) was 50% of that of the control cells. Moderate BmNPV-resistance caused by transgenesis of the artificial dsRNA-expressing gene was confirmed in the transgenic silkworms. Virus production was reduced in transgenic silkworms relative to controls up to 96 hrs after viral inoculation. Although complete protection was not achieved and the transgenic larvae ultimately died, this is the first report to show the use of RNAi in confering enhanced viral resistance on transgenic animals.

Glucose and ecdysteroid increase apyrene sperm production in in vitro cultivation of spermatocysts of Bombyx mori

Two types of sperm, nucleate eupyrene and anucleate apyrene, occur in the silkworm as in other lepidopteran species. Hormones and other substances have been assumed to play important roles in sperm dimorphism. We established an in vitro cultivation system for silkworm spermatocytes, and found that apyrene sperm are not produced when spermatocytes from larval testes are cultivated, though eupyrene spermatocytes develop normally into mature sperm. Based on the fact that ecdysteroid titers increase rapidly and peak 1 day after spinning, and that the amount of glycogen reaches its peak 1 day before the spinning stage, we studied the effects of adding glucose and/or 20-hydroxyecdysone to the culture medium. The experiments disclosed a significant additive effect of both substances on apyrene sperm production.

Meiotic pairing of sex chromosome fragments and its relation to atypical transmission of a sex-linked marker in Ephestia kuehniella (Insecta: Lepidoptera)

The physical basis of non-Mendelian segregation of a sex-linked marker was studied in sex- chromosome mutant females of eight ASF ('abnormal segregating females') lines in the flour moth, Ephestia kuehniella. Electron microscopical analysis of microspread synaptonemal complexes revealed that in one line, the Z chromosome segment that contained the dz+ allele was translocated onto an autosome. The resulting quadrivalent visible in early female meiosis was 'corrected' into two bivalents in later stages. This explains autosomal inheritance of the sex chromosome marker in this strain. In the other seven ASF lines, the type of meiotic pairing of an additional fragment (Zdz+) of the Z chromosome was responsible for abnormal segregation of the marker gene. In several of these lines, Zdz+ contained a piece of the W chromosome in addition to the Z segment, as was confirmed by comparative genomic hybridization (CGH). Zdz+ formed three alternative pairing configurations with the original sex chromosomes: (i) a WZZdz+ trivalent, (ii) a WZ bivalent and a Zdz+ univalent or (iii) a ZZdz+ bivalent and a W univalent. In the most frequent WZZdz+ configuration, Zdz+ synapsed with Z and, consequently, segregated with W, simulating W linkage. This explains the predominant occurrence of the parental phenotypes in the progeny. Zdz+ univalents or W univalents, on the other hand, segregated randomly, resulting in both parental and nonparental phenotypes. In two of these lines, the Zdz+ was transmitted only to females. The results suggest that the W chromosome segment in Zdz+ of these lines contains a male-killing factor which makes it incompatible with male development. Our data provide direct evidence for the regular transmission of radiation-induced fragments from lepidopteran chromosomes through more than 50 generations. This is facilitated by the holokinetic nature of lepidopteran chromosomes. We conclude that Zdz+ fragments may persist as long as they possess active kinetochore elements.

Significance of peristaltic squeezing of sperm bundles in the silkworm, Bombyx mori: elimination of irregular eupyrene sperm nuclei of the triploid

Silkworm (Lepidoptera) males produce dimorphic sperm: nucleate eupyrene sperm and anucleate apyrene sperm. The eupyrene sperm are ordinary sperm to fertilise the eggs, while the function of apyrene sperm remains uncertain. After meiosis, 256 sperm cells are enclosed by a layer of cyst cells, forming a sperm bundle. We have previously documented that the nucleus of eupyrene sperm anchors to the head cyst cell, which locates at the anterior apex of the bundle, by an acrosome tubule-basal body assembly. Neither the basal body attachment to the nucleus nor the acrosome is seen in apyrene sperm, and the nuclei remain in the middle region of the bundle. Peristaltic squeezing starts from the anterior of the bundles in both types of sperm, and cytoplasmic debris of the eupyrene sperm, and both the nuclei and debris of apyrene sperm, are eliminated at the final stage of spermatogenesis. Since the irregularity of meiotic division in apyrene sperm is known, we used triploid silkworm males that show irregular meiotic division even in eupyrene spermatocytes and are highly sterile. The irregular nuclei of the triploid are discarded by the peristaltic squeezing just as those of the apyrene sperm. Transmission electron microscopic observations disclose the abnormality in the acrosome tubule and in the connection to the basal body. The peristaltic squeezing of sperm bundles in the silkworm appears to be the final control mechanism to eliminate irregular nuclei before they enter female reproductive organs.

Peristaltic squeezing of sperm bundles at the late stage of spermatogenesis in the silkworm, Bombyx mori

Silkworm (Lepidoptera) males produce dimorphic sperm, nucleate eupyrene sperm, and anucleate apyrene sperm. The eupyrene sperm is the ordinary sperm fertilizing eggs, while the function of the apyrene sperm, which are about four times as numerous as the eupyrene sperm, is still uncertain. We found the peristaltic phenomenon at the very late stage of spermatogenesis. Peristalsis occurs in both eupyrene and apyrene sperm bundles. Through peristaltic action, cytoplasm of the eupyrene sperm and both cytoplasm and nuclei of the apyrene sperm are discarded from the posterior end of the sperm bundles. Peristaltic squeezing seems to be a process to eliminate the irregular nuclei of apyrene sperm while preserving the nuclei of eupyrene sperm.

[Epidemiological analysis of influenza B virus belonging to B/Victoria/2/87 lineage isolated in off-season of 1998 and late epidemic season in Shizuoka Prefecture]

In Shizuoka Prefecture, influenza B viruses belonging to B/Victoria/2/87 lineage caused an outbreak among school children in the off-season of 1998, and the same B viruses were mainly isolated during the following epidemic. Low titer of HI antibody among children for influenza B virus belonging to the same lineage was a recognized factor in the causation of the distinctive epidemic. The herald virus strains seemed to be antigenically similar to the late epidemic virus strains, but the former strains were not genetically close to the latter. This indicates that the herald viruses are not always the parental viruses for the following influenza season.

Analysis of proteins encoded in the bipartite genome of a new type of parvo-like virus isolated from silkworm - structural protein with DNA polymerase motif

Bombyx mori densonucleosis virus type 2 (BmDNV-2) is a small, spherical virus containing two complementary single-stranded linear DNA molecules (VD1, VD2). BmDNV-2 is a new type of virus with a unique, yet unspecified replication mechanism which is different from that of parvoviruses (Bando, H., Choi, H., Ito, Y., Nakagaki, M. , Kawase, S., 1992. Structural analysis on the single-stranded genomic DNAs of the virus newly isolated from silkworm: the DNA molecules share a common terminal sequence, Arch. Virol. 124, 187-193; Bando, H., Hayakawa, T., Asano, S., Sahara, K., Nakagaki, M. , Iizuka, T., 1995. Analysis of the genetic information of a DNA segment of a new virus from silkworm, Arch. Virol., 140, 1147-1155; Hayakawa, T., Asano, S., Sahara, K., Iizuka, T., Bando, H., 1997. Detection of replicative intermediate with closed terminus of Bombyx densonucleosis virus. Arch. Virol. 142, 1-7). Recent analyses on the genomic information of BmDNV-2 identified open reading frames which code for three tentative nonstructural proteins and four (VP1 to 4) of the six known structural proteins (Bando, H., Hayakawa, T., Asano, S., Sahara, K., Nakagaki, M., Iizuka, T., 1995. Analysis of the genetic information of a DNA segment of a new virus from silkworm, Arch. Virol., 140, 1147-1155; Nakagaki et al., in preparation). In this report we demonstrate that the two largest ORFs, VD1-ORF1 and VD2-ORF1, code for the two remaining structural proteins. In addition, computer-assisted analysis revealed that the structural protein encoded in VD1-ORF1 contains sequences conserved among various DNA polymerases, and showed an evolutionary relationship with the DNA polymerases involved in protein-primed replication.

TTAGG telomeric repeats in chromosomes of some insects and other arthropods

We studied the occurrence of the TTAGG telomere repeats by fluorescence in-situ hybridization (FISH) and Southern hybridization in ten insect species and two other arthropods. (TTAGG)n-containing telomeres were found in three Lepidoptera species, the silkworm Bombyx mori (in which the telomeric sequence was recently discovered), the flour moth Ephestia kuehniella, and the wax moth Galleria mellonella, in one species of Hymenoptera, the honey bee Apis mellifera, in one species of Coleoptera, the bark beetle Ips typographus, in one species of Orthoptera, the locust Locusta migratoria, and in a crustacean, the amphipod Gammarus pulex. They were absent in another species of Coleoptera, the mealworm Tenebrio molitor, two representatives of Diptera, Drosophila melanogaster and Megaselia scalaris, a species of Heteroptera, the bug Pyrrhocoris apterus and a spider, Tegenaria ferruginea. Our results, which confirm and extend earlier observations, suggest that (TTAGG)n was a phylogenetically ancestral telomere motif in the insect lineage but was lost independently in different groups, being replaced probably by other telomere motifs. In the Coleoptera this must have happened rather recently as even members of the same family, Curculionidae, differ with respect to the telomeric DNA.

Molecular differentiation of sex chromosomes probed by comparative genomic hybridization

Comparative genomic hybridization (CGH) was used to identify and probe sex chromosomes in several XY and WZ systems. Chromosomes were hybridized simultaneously with FluorX-labelled DNA of females and Cy3-labelled DNA of males in the presence of an excess of Cot-1 DNA or unlabelled DNA of the homogametic sex. CGH visualized the molecular differentiation of the X and Y in the house mouse, Mus musculus, and in Drosophila melanogaster: while autosomes were stained equally by both probes, the X and Y chromosomes were stained preferentially by the female-derived or the male-derived probe, respectively. There was no differential staining of the X and Y chromosomes in the fly Megaselia scalaris, indicating an early stage of sex chromosome differentiation in this species. In the human and the house mouse, labelled DNA of males in the presence of unlabelled DNA of females was sufficient to highlight Y chromosomes in mitosis and interphase. In WZ sex chromosome systems, the silkworm Bombyx mori, the flour moth Ephestia kuehniella, and the wax moth Galleria mellonella, the W chromosomes were identified by CGH in mitosis and meiosis. They were conspicuously stained by both female- and male-derived probes, unlike the Z chromosomes, which were preferentially stained by the male-derived probe in E. kuehniella only but were otherwise inconspicuous. The ratio of female:male staining and the pattern of staining along the W chromosomes was species specific. CGH shows that W chromosomes in these species are molecularly well differentiated from the Z chromosomes. The conspicuous binding of the male-derived probe to the W chromosomes is presumably due to an accumulation of common interspersed repetitive sequences.

Flow-through vascularized toe-joint transfer for reconstruction of segmental loss of an amputated finger

A segmental finger defect was reconstructed in a 46-year-old woman with a free flow-through vascularized toe-joint, including the proximal interphalangeal joint, the plantar digital nerve, and tendons of the second toe. The advantages of this composite flap are: (1) The segmental loss of the finger can be easily reconstructed to achieve a normal anatomic structure. (2) Excellent cosmesis is achieved, compared with conventional flaps such as the groin flap. (3) The distal segment of the donor toe can be preserved. (4) The transected digital arteries of the amputated finger can be simultaneously reconstructed with a flow-through arterial interposition. (5) The digital nerve can be repaired with a vascularized plantar digital nerve graft.

Analysis of genetic information of an insect picorna-like virus, infectious flacherie virus of silkworm: evidence for evolutionary relationships among insect, mammalian and plant picorna(-like) viruses

We synthesized the cDNAs of an insect picornavirus, infectious flacherie virus of silkworm (IFV), genomic RNA and inserted it into a bacterial plasmid (pUC119). The 9,650 nucleotides (nts) sequence except for the poly(A) tail was obtained from the cloned cDNAs, and the sequence integrity was confirmed by primer extension and direct RNA sequencing. The sequence has a large open reading frame (ORF) of 9,255 nts (3,085 codons) flanked by the short 5' non-coding region (156 nts) and by the rather long 3' non-coding (239 nts). The structural proteins VP3, 4, 1 and 2 were located at the N-terminus of the polyprotein in this order and were preceded by a tentative small peptide. Computer analysis identified the sequences similar to the consensus sequences of 2C (helicase?), 3C (protease), and 3D (RNA polymerase) conserved among mammalian and plant picorna(-like) viruses. In addition, the predicted genome organization of IFV was quite similar to those of picornaviruses. Further analyses of the characteristics of the genome structure and a tentative phylogenetic tree constructed on the basis of the amino acid sequence similarity emphasized the evolutionary relationships among the insect and plant viruses.

Detection of replicative intermediate with closed terminus of Bombyx densonucleosis virus

Two kinds of Bombyx densonucleosis virus (BmDNV), BmDNV-1 and 2, have been isolated from sericultural farms in Japan or China. These viruses are classified into the family Parvoviridae because of the small spherical virus particle containing a single-stranded linear DNA genome. Recent studies on the genome structure of these viruses suggested that BmDNV-2 was a new type of virus with unique replication mechanism, though that of BmDNV-1 was similar to parvoviruses. However, details about the replication mechanism of BmDNVs have not been reported so far. Here, in order to elucidate the difference on replication mechanism between BmDNVs and parvoviruses, we analyzed the structure of the replicative intermediate (RI) of BmDNV DNAs by PCR using specific primers designed for detection of RI with closed terminal structure (RI-CT) which is expected to be formed by replication with self-priming mechanism. PCR using the DNA from the cells infected with BmDNV-1 could detect the expected DNA fragment, showing the existence of RI-CT. On the other hand, no fragment could be amplified from the virion DNA of the BmDNVs and the DNA extracted from BmDNV-2-infected cells, respectively. These observations strongly suggested that the BmDNV-1 replicates with the "self-priming and hairpin-transfer" mechanism similar to the human parvoviruses, while BmDNV-2 does not.

[Invasive amebiasis at an institution for the mentally retarded in Shizuoka Prefecture]

Amebiasis caused by Entamoeba histolytica at an institution for mentally retarded in Shizuoka Prefecture is reported. Five of the 50 patients showed E. histolytica cysts in their stools and 4 were positive serologically. The polymerase chain reaction and restriction fragment length polymorphism revealed that the isolates were pathogenic-type E. histolytica. Epidemiological analysis revealed that the amebic infection was caused by the abnormal behavior of mentally retarded patients. Administration of diloxanide furoate and metronidazole for cyst-carriers eliminated cysts from the stool and lowered the antibody titer.

Analysis of the genetic information of a DNA segment of a new virus from silkworm

In 1983, a parvo-like virus (Yamanashi isolate) was newly isolated from silkworm. However, unlike parvovirus, two DNA molecules (VD1 and 2) were always extracted from purified virions. To investigate the structure and organization of the virus genomes, we determined the complete nucleotide sequence of VD2. The sequence consisted of 6031 nucleotides (nts) and contained a large open reading frame (ORF1) with 3513 nts. A smaller open reading frame (ORF2) with 702 nts was found in the complementary sequence. Computer analysis revealed that both ORFs did not code for the major structural proteins (VP1, 2, 3, and 4). These results suggest that VD2 has not enough information to produce progeny virions by itself. Further, the structural importance of the terminal sequence (CTS) common to both VD1 and VD2 was also predicted by a computer analysis.

Pathologic changes related to subcutaneous implantation of chlormadinone acetate for preventing estrus in bitches

Pathologic changes related to chlormadinone acetate (CAP) implantation were examined using 14 bitches given doses 2.5 to 25 mg/kg for 2 years. Absence of corpus luteum in bitches given 5 mg/kg or more supported long-term preventive effect of CAP on estrus. The uteri were dose-dependently enlarged and mucometra was occasionally found. Endometrial epithelium hyperplasia was observed but less in smaller doses. Changes in the mammary gland were only growth and lactation at normal degree. No remarkable changes were observed in ACTH and LH cells in the pituitary gland. Low, stable levels of CAP maintained in plasma by subcutaneous implantation seemed to be the main reason for absence or slight CAP-related pathologic changes.

Prevention of estrus in bitches by subcutaneous implantation of chlormadinone acetate

The efficacy and clinical safety of chlormadinone acetate (CAP) in preventing estrus were assessed in bitches on condition that CAP was subcutaneously implanted in silastic silicon rubber. To evaluate the long-term efficacy of implantation, 19 bitches were divided into 4 groups given doses of 2.5, 5, 10 and 25 mg/kg, respectively. Although estrus was observed within 13 months after implantation in all of the bitches given CAP in the 2.5 mg/kg dose, and in 13 to 15 months in 3 of the 5 bitches given the 5 mg/kg dose, it was prevented for at least 24 months in all of the bitches given doses of 10 mg/kg or more. Plasma progesterone levels remained low throughout the period of estrus prevention, indicating a close correlation with the effect of CAP. The mean body weight of the bitches in groups receiving higher doses increased slightly over the course of the experiment. Except this, no clinical, hematology or biochemistry abnormalities were found in any of the treated bitches. Another 6 bitches were given 10 to 30 mg/kg of CAP, but the implants were removed to observe the recurrence of estrus and to measure the amount of CAP in the removed implant. Estrus recurred after removal even in the bitch given 30 mg/kg. The concentrations of CAP in the plasma and the amounts of CAP remaining in the implants demonstrated the sustained release of CAP from the implants. The concentrations of CAP in the individual bitches indicated that the lowest concentration effective in preventing estrus is 0.7 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

[A waterborne outbreak of typhoid fever associated with a small drinking water supply system in Fuji city]

Fifteen cases of typhoid fever occurred in "HARADA" district Fuji City in Shizuoka Prefecture during the period of 1983 to 1985. Epidemiological and bacteriological investigations were carried out on the samples from a small water supply system, and drains of apartment houses in 1985. Water from a small river in the neighboring water supply system, and faecal specimens from people living in close proximity were investigated. The results obtained were as follows: 1) Salmonella typhi were isolated from 3/3 patients (1 pupil and 2 employees) in 1983, 3/5 patients (3 employees) in 1984, and from 4/7 patients (1 kindergartner, 1 pupil and 2 junior high school boys) in 1985. Phage type of these isolates were the same type "D1". 2) In the bacteriological survey on environment, S. typhi (phage type D1) were isolated from water of the water source of "HARADA" water supply in Fuji City with membrane filter methods, and from the sand source "HARADA" water supply with enrichment culture methods. Also, with an examination that tested 3,670 inhabitants, it was found that a carrier (phage type D1) was living near the "HARADA" water supply. 3) In the three selective media for the isolation of S. typhi, Bismuth sulfite agar (Difco) was the most sensitive, and detected 13 samples (61.9%) out of 21, from water source and sewage.

[Bacteriological and clinical evaluation of cefoxitin in the treatment of infections in 39 obstetric and gynecological patients]

A total of 39 patients was admitted to the obstetric and gynecological wards of Nagoya University Hospital and the University's 5 related hospitals during the period from July 1981 to March 1982. The efficacy of cefoxitin sodium was evaluated in the 39 patients with a wide variety of obstetric and gynecological infections. The findings are the follows: Of the 39 patients, the responses in 7 were judged "excellent", 28 "good" and 4 "poor" with the clinical efficacy rate of 89.7%. The causative pathogens in 23 of the cases were isolated from clinical materials submitted to the Institute of Anaerobic Bacteriology, School of Medicine, Gifu University. In these 23 cases, it was found that 8 were due to aerobic bacteria only (34.8%), 8 mixed aerobic-anaerobic bacteria (34.8%) and the remaining 6 anaerobic bacteria only (26.1%), i.e. a substantial percentage (60.9%) was due to anaerobic bacteria or mixed aerobic-anaerobic bacteria. Cefoxitin was active against most strains of Bacteroides spp. and was not affected by the inoculum size. On the other hand, most strains of Bacteroides spp. were resistant to cefazolin when the inoculum size was increased from 10(6)/ml to 10(8)/ml. Lincomycin was also found to be active against many fo the strains of Bacteroides spp. Cefoxitin and cefazolin were fairly active against anaerobic bacteria other than Bacteroides spp., while these same bacteria were resistant to sulbenicillin and many of them showed resistance to lincomycin. Cefoxitin was well tolerated and no untoward side effects were observed. The clinical and bacteriological results indicate that cefoxitin is a very effective antibiotic in the treatment of a wide variety of obstetric and gynecological infections and is a suitable choice as initial antibiotic therapy in these conditions.