Levy geometric graphs

We present a family of graphs with remarkable properties. They are obtained by connecting the points of a random walk when their distance is smaller than a given scale. Their degree (number of neighbors) does not depend on the graph's size but only on the considered scale. It follows a gamma distribution and thus presents an exponential decay. Levy flights are particular random walks with some power-law increments of infinite variance. When building the geometric graphs from them, we show from dimensional arguments that the number of connected components (clusters) follows an inverse power of the scale. The distribution of the size of their components, properly normalized, is scale invariant, which reflects the self-similar nature of the underlying process. This allows to test if a graph (including nonspatial ones) could possibly result from an underlying Levy process. When the scale increases, these graphs never tend towards a single cluster, the giant component. In other words, while the autocorrelation of the process scales as a power of the distance, they never undergo a phase transition of percolation type. The Levy graphs may find applications in community detection and in the analysis of collective behaviors as in face-to-face interaction networks.

Morphological differences in skulls and feeding apparatuses between Antarctic (Balaenoptera bonaerensis) and common (Balaenoptera acutorostrata) minke whales, and the implication for their feeding ecology

The differences in rorqual feeding ecology have been linked to the presence of different morphological markers. The Antarctic minke whale (Balaenoptera bonaerensis Burmeister, 1867) and the common minke whale (Balaenoptera acutorostrata Lacépède, 1804) are closely related species, but their morphological differences have not been fully investigated. In this study, we compared 21 skull and 11 feeding apparatus (baleen and mouth-related parts) measurement points between these two species using hundreds of individuals covering a wide range of body lengths in both sexes. Their engulfment capacities were estimated using these measurements. Our results show that Antarctic minke whales have (i) proportionally larger skulls to the body length, (ii) more dorsoventrally and laterally curved rostra, (iii) proportionally larger feeding apparatuses to the condylobasal length, and (iv) significantly larger engulfment capacity than common minke whales. These differences could indicate that Antarctic minke whales have developed a feeding strategy suitable for feeding on krill, which forms large schools. In contrast, common minke whales have adapted to prey on small pelagic fishes that are agile and form small schools.

Effective epidemic model for COVID-19 using accumulated deaths

The severe acute respiratory syndrome COVID-19 has been in the center of the ongoing global health crisis in 2020. The high prevalence of mild cases facilitates sub-notification outside hospital environments and the number of those who are or have been infected remains largely unknown, leading to poor estimates of the crude mortality rate of the disease. Here we use a simple model to describe the number of accumulated deaths caused by COVID-19. The close connection between the proposed model and an approximate solution of the SIR model provides estimates of epidemiological parameters. We find values for the crude mortality between 10 - 4 and 10 - 3 which are lower than estimated numbers obtained from laboratory-confirmed patients. We also calculate quantities of practical interest such as the basic reproduction number and subsequent increment after relaxation of lockdown and other control measures.

The Influence of Carbohydrate Structure on the Clearance of Recombinant Tissue-Type Plasminogen Activator

Modification of the carbohydrate structures of recombinant tissue-type plasminogen activator (rt-PA) can increase or decrease its rate of clearance in rabbits. When rt-PA was treated with sodium periodate to oxidize carbohydrate residues, the rate of clearance was decreased from 9.6 ± 1.9 ml min−1 kg−1 to 3.5 ± 0.6 ml min−1 kg−1 (mean ± SD, n = 5). A similar change in the clearance of rt-PA was introduced by the use of endo-β-N-acetyl- glucosaminidase H (Endo-H), which selectively removes high mannose asparagine-linked oligosaccharides; the clearance of Endo-H-treated rt-PA was 5.0 ± 0.5 ml min−1 kg−1. A mutant of rt-PA was produced with an amino acid substitution at position 117 (Asn replaced with Gin) to remove a potential glycosylation site that normally contains a high mannose structure. The clearance of this material was also decreased, similar to the periodate and Endo-H-treated rt-PA. Conversely, when rt-PA was produced in the CHO 15B cell line, which can produce only high mannose oligosaccharide structures on glycoproteins, the clearance was increased by a factor of 1.8. These results demonstrate that the removal of rt-PA from the blood depends significantly upon the nature of its oligosaccharide structures.

Enhancement of immune responses to an HBV DNA vaccine by electroporation

These studies document the ability of electroporation (EP)-based DNA vaccination to induce multi-specific CTL responses to hepatitis B virus (HBV) DNA vaccination in normal mice and marked immune responses to multivalent HBV DNA immunization in larger animal species. These results suggest that electroporation-mediated HBV DNA vaccination is worth pursuing as a treatment for chronic HBV infection.

Kidney-targeted naked DNA transfer by retrograde injection into the renal vein in mice

We recently developed a novel kidney-targeted gene transfer technique in rats, using the retrograde renal vein injection of naked plasmid DNA. Many animal disease models are created in mice by transgenic or knockout technologies. However, it is much harder to perform renal vein injection in mice than in rats because they have a thin and short vein. Here we transferred the mouse interleukin (IL)-10 gene into mice by retrograde renal vein injection, using an IL-10 and immunoglobulin fusion protein (IL-10/Fc) (96-kDa) expression plasmid, pCAGGS-IL10/Fc. We observed a dose-response relationship between serum IL-10 levels and the amount of injected DNA. The serum IL-10 levels peaked at day 1 and then were sustained for at least 2 weeks. These results demonstrate that the kidney-targeted naked plasmid DNA transfer of mice by retrograde renal vein injection can be achieved, and the kidney serves as a depot organ for the production of large proteins.

Structure and expression of 12-oxophytodienoate reductase (subgroup I) genes in pea, and characterization of the oxidoreductase activities of their recombinant products

Recently, we observed that expression of a pea gene (S64) encoding an oxophytodienoic acid reductase (OPR) was induced by a suppressor of pea defense responses, secreted by the pea pathogen Mycosphaerella pinodes. Because it is known that OPRs are usually encoded by families of homologous genes, we screened for genomic and cDNA clones encoding members of this putative OPR family in pea. We isolated five members of the OPR gene family from a pea genomic DNA library, and amplified six cDNA clones, including S64, by RT-PCR (reverse transcriptase-PCR). Sequencing analysis revealed that S64 corresponds to PsOPR2, and the amino acid sequences of the predicted products of the six OPR-like genes shared more than 80% identity with each other. Based on their sequence similarity, all these OPR-like genes code for OPRs of subgroup I, i.e., enzymes which are not required for jasmonic acid biosynthesis. However, the genes varied in their exon/intron organization and in their promoter sequences. To investigate the expression of each individual OPR-like gene, RT-PCR was performed using gene-specific primers. The results indicated that the OPR-like gene most strongly induced by the inoculation of pea plants with a compatible pathogen and by treatment with the suppressor from M. pinodes was PsOPR2. Furthermore, the ability of the six recombinant OPR-like proteins to reduce a model substrate, 2-cyclohexen-1-one (2-CyHE), was investigated. The results indicated that PsOPR1, 4 and 6 display robust activity, and PsOPR2 has a most remarkable ability to reduce 2-CyHE, whereas PsOPR3 has little and PsOPR5 does not reduce this compound. Thus, the six OPR-like proteins can be classified into four types. Interestingly, the gene structures, expression profiles, and enzymatic activities used to classify each member of the pea OPR-like gene family are clearly correlated, indicating that each member of this OPR-like family has a distinct function.

Hydrodynamics-based transfer of PCR-amplified DNA fragments into rat liver

A high level of plasmid DNA expression in rat liver can be achieved by the rapid injection of a large volume of a naked DNA solution into the tail vein, called the 'hydrodynamics-based procedure.' The preparation of PCR-amplified DNA fragments is easier than that of naked DNA. In this paper we evaluated the effects of expressing the erythropoietin (Epo) gene in the rat liver by injecting fCAGGS-Epo, an Epo-expressing PCR-amplified DNA fragment, via the tail vein. After injection of 5 pmol fCAGGS-Epo (10 microg) or pCAGGS-Epo (18.4 microg), plasmid DNA, the serum Epo levels peaked at week 1, then persisted for at least 12 weeks. Transgene-derived Epo secretion resulted in significant erythropoiesis. These results demonstrated that transfer of PCR-amplified DNA fragments into the rat liver via rapid tail vein injection can be achieved. This method may provide a useful means for studying the physiologic function of a putative gene.

Binding protein-3-selective insulin-like growth factor I variants: engineering, biodistributions, and clearance

Insulin-like growth factor I (IGF-I) is a potent anabolic peptide that mediates most of its pleiotropic effects through association with the IGF type I receptor. Biological availability and plasma half-life of IGF-I are modulated by soluble binding proteins (IGFBPs), which sequester free IGF-I into high affinity complexes. Elevated levels of specific IGFBPs have been observed in several pathological conditions, resulting in inhibition of IGF-I activity. Administration of IGF-I variants that are unable to bind to the up-regulated IGFBP species could potentially counteract this effect. We engineered two IGFBP-selective variants that demonstrated 700- and 80,000-fold apparent reductions in affinity for IGFBP-1 while preserving low nanomolar affinity for IGFBP-3, the major carrier of IGF-I in plasma. Both variants displayed wild-type-like potency in cellular receptor kinase assays, stimulated human cartilage matrix synthesis, and retained their ability to associate with the acid-labile subunit in complex with IGFBP-3. Furthermore, pharmacokinetic parameters and tissue distribution of the IGF-I variants in rats differed from those of wild-type IGF-I as a function of their IGFBP affinities. These IGF-I variants may potentially be useful for treating disease conditions associated with up-regulated IGFBP-1 levels, such as chronic or acute renal and hepatic failure or uncontrolled diabetes. More generally, these results suggest that the complex biology of IGF-I may be clarified through in vivo studies of IGFBP-selective variants.

High prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium in female commercial sex workers in Japan

Our objectives were to explore the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium in Japanese female commercial sex workers (CSWs), in comparison with pregnant women as controls. A high-risk group of 174 female CSWs and 90 asymptomatic pregnant women were enrolled in this study. Detection of C. trachomatis, N. gonorrhoeae, and M. genitalium on the endocervix of the women was performed mainly by using polymerase chain reaction (PCR)-based assays. The prevalence rates of C. trachomatis, N. gonorrhoeae, and M. genitalium were 19.0%, 32.8%, and 12.6%, respectively, in the CSWs, compared with 5.6%, 0%, and 1.1% respectively, in the pregnant women. These results suggest a high prevalence of C. trachomatis, N. gonorrhoeae, and M. genitalium in Japanese CSWs. We conclude that continued close monitoring of the prevalence of C. trachomatis, N. gonorrhoeae, and M. genitalium infection in CSWs is important for preventing the dissemination of these microorganisms, and that further investigation of M. genitalium as a sexually transmitted pathogen in women is needed.

Eosinophilia of dystrophin-deficient muscle is promoted by perforin-mediated cytotoxicity by T cell effectors

Previous investigations have shown that cytotoxic T lymphocytes (CTLs) contribute to muscle pathology in the dystrophin-null mutant mouse (mdx) model of Duchenne muscular dystrophy through perforin-dependent and perforin-independent mechanisms. We have assessed whether the CTL-mediated pathology includes the promotion of eosinophilia in dystrophic muscle, and thereby provides a secondary mechanism through which CTLs contribute to muscular dystrophy. Quantitative immunohistochemistry confirmed that eosinophilia is a component of the mdx dystrophy. In addition, electron microscopic observations show that eosinophils traverse the basement membrane of mdx muscle fibers and display sites of close apposition of eosinophil and muscle membranes. The close membrane apposition is characterized by impingement of eosinophilic rods of major basic protein into the muscle cell membrane. Transfer of mdx splenocytes and mdx muscle extracts to irradiated C57 mice by intraperitoneal injection resulted in muscle eosinophilia in the recipient mice. Double-mutant mice lacking dystrophin and perforin showed less eosinophilia than was displayed by mdx mice that expressed perforin. Finally, administration of prednisolone, which has been shown previously to reduce the concentration of CTLs in dystrophic muscle, produced a significant reduction in eosinophilia. These findings indicate that eosinophilia is a component of the mdx pathology that is promoted by perforin-dependent cytotoxicity of effector T cells. However, some eosinophilia of mdx muscle is independent of perforin-mediated processes.

Correlation between microvessel density and tumor cell proliferation with clinical factors in breast carcinomas

Fifty-nine methacarn-fixed, paraffin-embedded human breast carcinomas were immunostained by QB-END/10 (an antibody to CD34 antigen) to observe microvessels and by PC10 (an antibody to proliferating cell nuclear antigen; PCNA) to determine tumor cell proliferation; 9 normal human breast tissue specimens were also immunostained by QB-END/10. The number of microvessels in the periphery of the breast carcinoma was significantly greater than both that in the center of the breast carcinoma and that in the normal breast. There was also a significant relationship between the number of microvessels in the periphery of breast carcinomas and the histological tumor size and lymph node status. However, there was no significant relationship between the tumor cell proliferation activity (PCNA positive cell ratio) and any clinical or histopathological variables. The number of microvessels and the tumor cell proliferation activity showed a weak negative correlation.

Ablation depths and morphological changes in human enamel and dentin after Er:YAG laser irradiation with or without water mist

OBJECTIVE

This investigation was performed quantitatively to determine the ranges of ablation and to evaluate the morphological changes in human enamel and dentin irradiated by Er:YAG laser with or without water mist.

SUMMARY BACKGROUND DATA

Recently, several infrared lasers have been introduced in the dental clinic to remove carious dental hard tissues in anticipation of replacing the high-speed dental drill. Among them, the Er:YAG laser has shown the most promise for hard tissue ablation.

METHODS

An Er:YAG laser was used to ablate human dental hard tissues using a pulse energy that ranged from 100 to 400 mJ at a frequency of 2 Hz for 5 seconds. Ablation rates with or without water mist at different pulse energies were measured, and the morphological changes on enamel and dentin were also investigated by stereomicroscopy and scanning electron microscopy (SEM).

RESULTS

The relationship between ablation depths and energies was almost linear at both enamel and dentin samples. The irradiation with water mist reduced the ablation depths, but only minimally, when compared to those irradiated without water mist. Morphological findings by SEM indicated that Er:YAG laser irradiation with water mist could produce the cavities without signs of thermal damage to the surrounding enamel and dentin.

CONCLUSIONS

The results of this study suggest that addition of a fine water mist directed at the ablation sites does not greatly decrease the ablation, and does not cause any carbonization and melting in the surrounding dental hard tissues.

Immunohistochemical study of mammary and extramammary Paget's disease

Immunophenotypes of mammary (MPD) and extramammary Paget's disease (EPD) are still not well understood. Thirty-four formalin-fixed paraffin-embedded tissue sections from 33 patients with 6 MPD and 28 EPD were studied immunohistochemically with the use of polyclonal c-erbB-2 and pS2 antisera, and monoclonal nm23, B6.2, GCDFP-15, and p53 antibodies. Cases of MPD expressed a high incidence of c-erbB-2 and nm23 compared with those of EPD (100% vs. 29%; p < 0.01, and 83% vs. 29%; p < 0.05, respectively). Although high expression of B6.2 (> 83%) and moderate expression of GCDFP-15 (33-39%), pS2 (33-46%) and p53 (39-50%) were seen, the positivity was not significantly different between MPD and EPD. These findings indicate that MPD and EPD share immunohistochemical features but partially differ in their patterns of antigen expression.

Effects of two different doses of leuprolide acetate depot on uterine cavity area in patients with uterine leiomyomata

OBJECTIVE

To compare the effects of two different doses of a monthly depot injection of a GnRH agonist (GnRH-a) on uterine cavity area in patients with uterine leiomyomata.

DESIGN

Prospective, randomized study.

SETTING

Hospital department of obstetrics and gynecology.

PATIENTS

Thirty-six premenopausal women, 25 to 52 years of age, with uterine leiomyomata.

INTERVENTION

Leuprolide acetate (LA) depot, 1.88 or 3.75 mg, was administered SC every 4 weeks for 24 weeks.

MAIN OUTCOME MEASURE

Uterine cavity area before and after treatment was assessed by hysterosalpingography.

RESULTS

The 1.88- and 3.75-mg LA depots significantly reduced uterine cavity area by 40.8% and 40.2%, respectively. No significant difference was observed between the two groups.

CONCLUSION

Monthly injection of 1.88 or 3.75 mg LA depots appears to reduce uterine cavity area to a similar extent in patients with uterine leiomyomata.

Cytotoxic cells directed against placental cells detected in human habitual abortions by an in vitro terminal labeling assay

PROBLEM

From the clinical point of view, it has been proposed that an immunological imbalance between the mother and the fetus might exist in one of the mechanisms for human habitual abortion. However, in the definition of habitual abortion, we have no distinct immunological criteria for this clinical entity at the moment.

METHOD

We employed aborted placental cells as the target cells in an in vitro terminal labeling (IVTL) assay system, in which the cytotoxic activity of maternal peripheral blood mononuclear cells (PBMCs) against the placental cell was examined.

RESULTS

Our results showed that the cytotoxic activity of maternal PBMCs was significantly higher in the habitual aborters (the mean target cell destruction: %TCD = 34.9%, N = 14) than that in the women with a normal first trimester (the mean % TCD = 8.9%, N = 14, P < .01). The results from the IVTL assay did not correlate with other assays using paternal lymphocytes as the target cells. The surface marker analyses revealed that CD16+ cells, CD14+ cells, and CD5+ cells were involved in the cytotoxic response against the placental cells in various degrees among the cases.

CONCLUSIONS

The above evidence suggests that a variety of cytotoxic cells participate in the phenomenon of human habitual abortion.

A rapid microassay for dichloroacetate in serum by gel-permeation chromatography

We have developed a novel, rapid microassay for dichloroacetate in the serum. The serum sample is directly injected into a gel-permeation high-performance liquid chromatography apparatus. The peak of dichloroacetate appears after a giant protein peak. The method requires a very small amount of serum (10 microliters), and the analysis time is short (20 min). Using this micro method, we measured the serum concentrations of dichloroacetate in healthy adult volunteers and paediatric patients with congenital lactic acidosis. Although the effect of dichloroacetate on the neurological manifestations of congenital lactic acidosis has not been proved to be beneficial, the potential usefulness of dichloroacetate in refractory lactic acidosis in cardiac and respiratory failure has been recognized, and human as well as animal studies have been undertaken in many laboratories. To prevent possible side effects of dichloroacetate, it has been recommended that the minimal effective dose be used. Our microassay method is useful for both human and animal experiments, even after administration of minimal doses.

Changes in phospholipase A2 activity of the rabbit ampullary epithelium by ovarian steroids

Phospholipase A2 (EC 3.1.1.4) activity of the ampullary epithelium from rabbit oviducts was compared in the presence of various ovarian steroids to assess how they could modulate prostaglandins (PG) biosynthesis in the oviduct. The phospholipase A2 (PLA2) activity of the cells from ovariectomized rabbits (control) was 190.8 +/- 9.8 pmol/min/mg. The PLA2 activity of the cells from progesterone-treated rabbits was 156.0 +/- 41.8 pmol/min/mg and was not significantly different from the control activity. However, the PLA2 activity of the cells from the estrogen-treated rabbits was 233.5 +/- 29.0 pmol/min/mg, which was significantly higher than the control activity (p < 0.05). On the other hand, the PLA2 activity of the cells from progesterone-treated rabbits after being primed with estrogen was 116.3 +/- 25.9 pmol/min/mg, which was significantly lower than the control activity (p < 0.01). These results suggest that the effects on PLA2 activity of ovarian steroids could regulate the local production of PG which plays a role in both smooth muscle contractility and ciliary activity.

Regional differences of phospholipase A2 activity in the rabbit oviductal epithelium

To evaluate the biosynthesis of prostaglandins in the oviducts, phospholipase A2 (EC 3.1.1.4) activities were first measured in the epithelial cells obtained from rabbit oviducts. At least four kinds of phospholipase A2 (PLA2) activities with respect to calcium dependency and pH requirement were observed. There were two calcium-dependent, pH optima of 7.5 and 8.5 activities, and two calcium-independent, pH optima of 4.0 and 8.0 activities. One of those activities, a calcium-dependent and alkaline active PLA2 activity of the epithelial cells was then compared between the ampullary portion and the isthmic portion of the oviducts. The activity was significantly higher in the ampullary epithelium than in the isthmic epithelium (223.2 +/- 57.2 or 103.8 +/- 32.3 pmol/min/mg, p < 0.05). These results support the idea that the production of prostaglandins, which is dependent upon the activity of the arachidonate cascades, was higher in the ampullary portion of oviduct than that in the isthmic portion. The PLA2 activity of the ampullary epithelium may thus play an important role in the regulation of smooth muscle contractility and ciliary movement.

Efficacy of a low-dose leuprolide acetate depot in the treatment of uterine leiomyomata in Japanese women

OBJECTIVE

To compare the efficacy of two different doses, 1.88 mg and 3.75 mg, of a monthly depot injection of a gonadotropin-releasing hormone agonist (GnRH-a) in the treatment of uterine leiomyomata.

DESIGN

A prospective randomized study.

SETTING

Hospital department of gynecology and obstetrics.

PATIENTS

Forty-one premenopausal Japanese women, 25 to 53 years of age, with uterine leiomyomata.

INTERVENTIONS

Depot type of GnRH-a, leuprolide acetate (LA) 1.88 mg or 3.75 mg was administered subcutaneously every 4 weeks for 24 weeks.

MAIN OUTCOME MEASURES

Efficacy of treatment was assessed in terms of uterine volume, serum levels of estradiol (E2), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and adverse symptoms during treatment.

RESULTS

In both groups, a significant reduction in uterine volume, 52% in 1.88 mg group and 47% in 3.75 mg group, was obtained at week 24, with near maximal reduction (41%, 45%) apparent by 12 weeks. No significant difference was observed between the groups in percent uterine volume reduction at each treatment week. Both groups showed significant and equal suppression of serum levels of E2, LH, and FSH. In addition, the incidence of adverse symptoms was not significantly different between the two groups.

CONCLUSIONS

Monthly injection of 1.88 mg or 3.75 mg LA depot has equivalent treatment efficacy in reducing uterine volume. Twelve weeks of treatment is enough to obtain near maximal reduction.

Cervical cancers in uterus didelphys

Two cases of cervical cancer in uterus didelphys are presented. One was extensive adenocarcinoma and one was squamous cell carcinoma in situ. In both cases the cancers appeared to have originated separately in each cervix.

Vascular pedicle transposition of an ovary with subsequent intrauterine pregnancy

In a patient who underwent both a right salpingectomy because of right tubal pregnancy and left ovarian cystectomy due to an ovarian cyst, we performed an operation whereupon the normal right ovary was shifted toward the position of the left ovary together with the pelvic infundibular ligament. By observation of the ovarian follicle through ultrasonic tomography, the follicle, as seen only from the right preoperatively, was seen only from the left after the operation. The patient delivered a baby by normal pregnancy 3 months after the operation. This method requires no complicated technique and could prove to be a promising therapeutic procedure treating patients with infertility.

Effects of lathyrogens on the mechanical strength of the periodontal ligament in the rat mandibular first molar

Effects of lathyrogens such as aminoacetonitrile (AAN), beta-aminopropionitrile (BAPN) and cysteamine--known inhibitors of cross-linking of collagen--on the mechanical strength of the periodontal ligament of the rat mandibular first molar were examined by measuring the ultimate load required to extract the tooth from its socket in the dissected jaw. Single injections of AAN (40 approximately 100 mg/100 g body weight) or of BAPN (100 mg/100 g body weight) caused significant decreases of the mechanical strength 24 h after administration of the drugs but that of cysteamine (30 mg/100 g body weight) did not. Significant correlations between the dose of AAN or of BAPN and the mechanical strength were found following daily administrations of the drugs for 5 days. The relative potency of AAN to BAPN was estimated to be 4.5 by a slope ratio assay. The rapid appearance and disappearance of the effect of lathyrogens on the mechanical strength of the periodontal ligament of the rat mandibular first molar provide further evidence that the turnover of the collagen in the tissue is fast. The half-time of collagen synthesis was estimated to be approximately 3 d.

Expression and immunogenicity of the extracellular domain of the human immunodeficiency virus type 1 envelope glycoprotein, gp160

The envelope glycoprotein of human immunodeficiency virus type 1 is synthesized as a precursor, gp160, that subsequently is cleaved to yield mature gp120 and gp41. In these studies, the gene encoding gp160 was mutagenized so as direct the synthesis of a truncated protein consisting of the extracellular domains of both gp120 and gp41. The variant protein, termed sgp160, consisted of 458 amino acids of gp120 and 172 amino acids of gp41. To facilitate protein purification, the normal polyglycoprotein processing site between gp120 and gp41 was deleted through the use of site-directed mutagenesis. This allowed for the synthesis of a molecule that could be purified by affinity chromatography, using acid elution, without dissociation of the gp120 polypeptide from the gp41 polypeptide. The conformation of the sgp160 variant appeared to be functionally relevant, as reflected by its ability to bind to CD4 with an affinity comparable to that of the variant rgp120. The structure of the sgp160-containing polypeptide differed from that of rgp120 in that it tended to form high-molecular-weight aggregates that could be dissociated to monomers and dimers in the presence of reducing agents. Antibodies against the sgp160 protein reacted with authentic virus-derived gp160, gp120, and gp41; neutralized viral infectivity; and inhibited the binding of rgp120 to CD4. Rabbit antibodies to the sgp160 protein differed from those raised against rgp120 in that they were enriched for populations that blocked CD4 binding but did not prevent human immunodeficiency virus type 1-induced syncytium formation.

Two-dimensional pulsed Doppler echocardiographic technique for estimating pulmonary to systemic blood flow ratio in children with atrial septal defect and patent ductus arteriosus

A two-dimensional pulsed Doppler echocardiographic method was evaluated for quantifying the pulmonary (Qp) to systemic (Qs) blood flow ratio. Twenty six patients were studied, 15 with atrial septal defect (ASD) and 11 with patent ductus arteriosus (PDA). An apical four-chamber view was used to measure the maximal Doppler flow velocities in the right and left ventricular inflow regions (RVIR and LVIR) and the maximal diameters of the tricuspid and mitral anuli at diastole. The two-dimensional pulsed Doppler pulmonary to systemic blood flow ratio (Qp/Qs) estimation involved calculating the area of the Doppler flow velocity signal along the time scale multiplied by the diameter of either the tricuspid or mitral anulus as measured on the apical four-chamber view. In ASD patients, Qp was measured at RVIR and Qs at LVIR. In PDA patients, Qp was calculated at LVIR and Qs at RVIR. Twenty-six healthy children comprised the control group. The areas of the Doppler flow velocity signals along the time scales of RVIR and LVIR were also quantified and the diameters of the tricuspid and mitral anuli were measured. In the control group, the linear correlation of the trans-mitral M(d)*M(a) to trans-tricuspid T(d)*T(a) value was r = 0.909, n = 26. The correlations between Doppler Qp/Qs ratio estimates and those obtained at cardiac catheterization were r = 0.902, n = 15 in ASD and r = 0.967, n = 11 in PDA. These results suggest a clinical application of this Doppler echocardiographic method in the noninvasive estimation of the cardiac shunt in ASD and PDA.

Environment: peculiar pigment cell neoplasm in fish

Chromatophoroma in the croaker (Nibea mitsukurii) showed a unique geographic distribution. The contribution of environmental chemicals to the cause of chromatophoroma in the feral croaker is considered likely on the basis of the following results in our studies. 1) Chromatophoroma was induced in tank-reared N. mitsukurii by administration of certain kinds of known carcinogens such as 7,12-dimethyl-benz(a)anthracene, N-methyl-N'-nitro-N-nitrosoguanidine, and nifurpirinol. 2) Local accumulation of pigment-cell hyperplasia in the catfish (Protosus anguillaris) showed similar tendencies to those of chromatophoroma in N. mitsukurii. 3) Removal of contaminated sediment from the harbor and the river appeared to reduce the incidence from 47% in 1973-1983 to about 20% in 1985-1987. 4) Waste water from a factory located at the station where the incidence of the neoplasm was the highest contained mutagenic substances such as chloroacetones and glyoxals [5]. Exposure of catfish to the waste water induced pigment-cell hyperplasia on the skin.

Evaluation and comparison of the axis of the interventricular septum by two-dimensional echocardiography among the patients with congenital heart disease (ASD, VSD, PDA, PS, TOF) and the normal subjects

A two-dimensional echocardiographic method was applied to determine the axis of interventricular septum (IVS) in the horizontal plane. This study comprised 19 subjects with ASD, 15 subjects with VSD(I), 20 subjects with VSD(II), 13 subjects with PDA, 16 subjects with PS, 15 subjects with TOF and 99 normal children. Parasternal left ventricular short axis view was taken, and the IVS was recorded by using the polaroid prints. The axis of the IVS in the horizontal plane was measured from the recorded polaroid prints. The value of the angularity of IVS (IVS-A) expressed as means +/- one standard deviation (mean +/- 1S.D.) is 52.0 +/- 13.7 degrees in ASD, 42.2 +/- 9.7 degrees in VSD(I), 43.7 +/- 9.1 degrees in VSD(II), 41.6 +/- 11.4 degrees in PDA, 38.6 +/- 10.9 degrees in PS, 61.0 +/- 8.5 degrees in TOF and 40.1 +/- 8.2 degrees in normal controls. There was no significant difference among VSD(I), VSD(II), PDA, PS and normal controls but a highly significant difference was noted in ASD and TOF as compared to other groups. The correlation coefficient of the IVS-A with (1) the Qp/Qs ratio, (2) the magnitude of shunt (%), (3) the right ventricular pressure and (4) the hematocrits were evaluated among the patient groups. The IVS-A of ASD and VSD(II) had a good correlation with the shunt flow (r = 0.921 and 0.88 respectively) and/or the Qp/Qs ratio (r = 0.782 and 0.955 respectively); while that of VSD(I), PDA, and PS had a good correlation with the right ventricular pressure (r = 0.956, 0.953, 0.842 respectively) and that of TOF was mostly concerned with the hematocrits (r = 0.911). Besides, the IVS-A in each severe CHD subgroup was significantly (p less than 0.005 or a better value) higher than the normal control group. Thus an alternative method was validated for evaluating the severity of congenital heart disease by using a noninvasive two-dimensional echocardiographic technique.

Dating sonographic endometrial images in the normal ovulatory cycle

Pelvic sonograms were obtained from 5 fertile volunteers and 150 infertile patients with normal ovulatory cycles, using real-time ultrasound. The existence of a linear cavity echo (C), thick hypoechoic layer (H) and increased echogenicity (E) were chosen as the parameters of sonographic endometrial images to be studied for dating the ovulatory cycle. In 109 serial sonograms from the fertile volunteers, H was observed from 3 days before ovulation (day -3) to ovulation day (day 0). E was observed from day +1 to day +8, and C, from day -10 to day +3. Studies on 189 sonograms from the infertile patients revealed a similar pattern for these parameters. We tested the accuracy of sonographic images of the endometrium, using sonograms from five patients who underwent hysterectomy. The measurements of endometrial thickness, in vivo, and in vitro, showed little difference. Sonographic endometrial images are considered indicative of histological changes, under the influence of estradiol and progesterone. Therefore, observation of the combined quantitative changes in C, H and E facilitates dating of the sonographic endometrial images in a normal ovulatory cycle.

Sonographic study of the endometrial responses to ovarian hormones in patients receiving ovarian stimulation

A total of 486 endometrial sonograms from 60 cases were reviewed to study the endometrial responses. There was a significant change in the proportion of each sonographic criterion between the pre- and post-ovulatory phases. After ovulation endometrial image showed distinct changes, and its thickness increased. These results suggest that classification of endometrial sonograms according to criteria and thickness measurements provides useful information.

Epitope mapping of the human immunodeficiency virus type 1 gp120 with monoclonal antibodies

A soluble form of recombinant gp120 of human immunodeficiency virus type 1 was used as an immunogen for production of murine monoclonal antibodies. These monoclonal antibodies were characterized for their ability to block the interaction between gp120 and the acquired immunodeficiency syndrome virus receptor, CD4. Three of the monoclonal antibodies were found to inhibit this interaction, whereas the other antibodies were found to be ineffective at blocking binding. The gp120 epitopes which are recognized by these monoclonal antibodies were mapped by using a combination of Western blot (immunoblot) analysis of gp120 proteolytic fragments, immunoaffinity purification of fragments of gp120, and antibody screening of a random gp120 gene fragment expression library produced in the lambda gt11 expression system. Two monoclonal antibodies which blocked gp120-CD4 interaction were found to map to adjacent sites in the carboxy-terminal region of the glycoprotein, suggesting that this area is important in the interaction between gp120 and CD4. One nonblocking antibody was found to map to a position that was C terminal to this CD4 blocking region. Interestingly, the other nonblocking monoclonal antibodies were found to map either to a highly conserved region in the central part of the gp120 polypeptide or to a highly conserved region near the N terminus of the glycoprotein. N-terminal deletion mutants of the soluble envelope glycoprotein which lack these highly conserved domains but maintain the C-terminal CD4 interaction sites were unable to bind tightly to the CD4 receptor. These results suggest that although the N-terminal and central conserved domains of intact gp120 do not appear to be directly required for CD4 binding, they may contain information that allows other parts of the molecule to form the appropriate structure for CD4 interaction.

The influence of carbohydrate structure on the clearance of recombinant tissue-type plasminogen activator

Modification of the carbohydrate structures of recombinant tissue-type plasminogen activator (rt-PA) can increase or decrease its rate of clearance in rabbits. When rt-PA was treated with sodium periodate to oxidize carbohydrate residues, the rate of clearance was decreased from 9.6 +/- 1.9 ml min-1 kg-1 to 3.5 +/- 0.6 ml min-1 kg-1 (mean +/- SD, n = 5). A similar change in the clearance of rt-PA was introduced by the use of endo-beta-N-acetyl-glucosaminidase H (Endo-H), which selectively removes high mannose asparagine-linked oligosaccharides; the clearance of Endo-H-treated rt-PA was 5.0 +/- 0.5 ml min-1 kg-1. A mutant of rt-PA was produced with an amino acid substitution at position 117 (Asn replaced with Gln) to remove a potential glycosylation site that normally contains a high mannose structure. The clearance of this material was also decreased, similar to the periodate and Endo-H-treated rt-PA. Conversely, when rt-PA was produced in the CHO 15B cell line, which can produce only high mannose oligosaccharide structures on glycoproteins, the clearance was increased by a factor of 1.8. These results demonstrate that the removal of rt-PA from the blood depends significantly upon the nature of its oligosaccharide structures.

Km mutant of acid alpha-glucosidase in a case of cardiomyopathy without signs of skeletal muscle involvement

A male patient is reported with a mutation of acid alpha-glucosidase causing an altered Km toward natural substrates. Cardiac arrhythmia was found at 12 years of age, and he died of heart failure at 15 years. No skeletal muscle involvement was observed either clinically or histologically. Acid alpha-glucosidase activity in fibroblasts was moderately low (43% of the control mean) with normal Km for 4-methylumbelliferyl alpha-D-glucoside. The hydrolysis of glycogen was markedly decreased (14% of the control mean), and the Km for maltose was increased 4-fold and for glycogen 5-fold. The biosynthesis and the posttranslational processing of the mutant enzyme appeared normal, but the total amount of the enzyme was lower than normal. This mutant enzyme comigrated with normal acid alpha-glucosidase on starch gel electrophoresis, and not with the rare isozyme, acid alpha-glucosidase 2. A possible role of this mutant enzyme in the pathogenesis of this disease and the relationship to glycogenesis II are discussed.

[Study on relationships between sonographic endometrial images and ovarian hormone levels]

Sixty-seven and 109 sonographic endometrial images obtained from 67 infertile patients and 5 healthy volunteers with normal ovulatory cycles, respectively, were investigated with regard to serum estradiol (E2) and progesterone (P) levels. The ultrasound devices used were sector electronic scanners (3.5 MHz). 1) Endometrial images were able to be classified into four pattern types, according to the criteria reported by Sakamoto (1985), using a gray-scale contact compound scan. Pattern 1: linear cavity echo, pattern 2: thick hypoechoic endometrium surrounded by thin border echo, pattern 3: thickened border echo, pattern 4: entire echogenic endometrium. 2) Both E2 and P levels were low in pattern 1. The E2 level was significantly higher in pattern 2 than in pattern 1 (p less than 0.01), indicating pattern 2 reflects E2 surges prior to ovulation. The P level was high in pattern 3; and in pattern 4, it was significantly higher than in patterns 1 and 2 (p less than 0.01), indicating that patterns 3 and 4 are in the early and mid-luteal phase, respectively. 3) Sonograms obtained from 12 cases with suspicious luteal phase defects showed an abnormal pattern in the mid-luteal phase. These results indicate that the sonographic endometrial images reflect respective ovarian hormone levels.

Delineation of a region of the human immunodeficiency virus type 1 gp120 glycoprotein critical for interaction with the CD4 receptor

The primary event in the infection of cells by HIV is the interaction between the viral envelope glycoprotein, gp120, and its cellular receptor, CD4. A recombinant form of gp120 was found to bind to a recombinant CD4 antigen with high affinity. Two gp120-specific murine monoclonal antibodies were able to block the interaction between gp120 and CD4. The gp120 epitope of one of these antibodies was isolated by immunoaffinity chromatography of acid-cleaved gp120 and shown to be contained within amino acids 397-439. Using in vitro mutagenesis, we have found that deletion of 12 amino acids from this region of gp120 leads to a complete loss of binding. In addition, a single amino acid substitution in this region results in significantly decreased binding, suggesting that sequences within this region are directly involved in the binding of gp120 to the CD4 receptor.

[Maternal beta-endorphin secretion during pregnancy--measurement of immunoreactive beta-endorphin in urine]

Gestational variations in maternal beta-endorphin (beta-end) secretion were investigated by simultaneous measurements of plasma and urinary immunoreactive beta-endorphin (ir-beta-end). Urinary ir-beta-end was extracted by using a Sep-Pak C18 column and was found to be stable for at least 24 hours at room temperature. Plasma and urine (2 hour collection) samples were obtained from 41 pregnant women and 7 non-pregnant women. Almost parallel increases in plasma and urinary ir-beta-end were observed during the course of pregnancy and there was a good correlation between them. Compared with non-pregnant values, significant increases (p less than 0.001) were observed after 36 weeks of gestation. We also studied chromatographic patterns of urinary extracts of non-pregnant and pregnant women. Both of them consist of 4 peaks and resemble each other. They were essentially similar to those of plasma extracts except for the third peak which appeared between the elution position of beta-lipotropin (beta-LPH) and beta-end. In conclusion, maternal beta-end secretions increase in late gestation not only in plasma but also in urine.

A novel macromolecular antibiotic, SN-07. Taxonomy of producing organism, isolation, characterization and biological activities

A novel macromolecular antibiotic SN-07 was obtained from the cultural supernatant of Actinomadura roseoviolacea var. miuraensis nov. var. The antibiotic was soluble in water, had a molecular weight of 18,000-22,000 daltons in 50 mM Tris-HCl buffer, pH 7.0, containing 2.0 M KCl as compared with authentic proteins. Its major constituents were nucleic acids. The substance had antibacterial activity against Gram-positive bacteria. It was also effective against lymphocytic leukemia P388 in vivo.

A new species of Actinomadura producing a polyether antibiotic, cationomycin

Taxonomic studies on the new species, Actinomadura azurea are presented. A significant property of this species is the production of a new polyether antibiotic, cationomycin.