Reduction in overweight and obesity from a 3-year community-based intervention in Australia: the 'It's Your Move!' project

'It's Your Move!' was a 3-year intervention study implemented in secondary schools in Australia as part of the Pacific Obesity Prevention In Communities Project. This paper reports the outcome results of anthropometric indices and relevant obesity-related behaviours. The interventions focused on building the capacity of families, schools and communities to promote healthy eating and physical activity. Baseline response rates and follow-up rates were 53% and 69% respectively for the intervention group (n=5 schools) and 47% and 66% respectively for the comparison group (n=7 schools). Statistically significant relative reductions in the intervention versus comparison group were observed: weight (-0.74 kg, P < 0.04), and standardized body mass index (-0.07, P<0.03), and non-significant reductions in prevalence of overweight and obesity (0.75 odds ratio, P=0.12) and body mass index (-0.22, P=0.06). Obesity-related behavioural variables showed mixed results with no pattern of positive intervention outcomes. In conclusion, this is the first study to show that long-term, community-based interventions using a capacity-building approach can prevent unhealthy weight gain in adolescents. Obesity prevention efforts in this important transitional stage of life can be successful and these findings need to be translated to scale for a national effort to reverse the epidemic in children and adolescents.

Bronchobiliary fistula successfully treated surgically

Bronchobiliary fistula is a rare condition, arising as a complication of hydatid disease of the liver, hepatic tuberculosis, hepatic malignancy, chronic pancreatitis, hepatic trauma or surgery. Patients characteristically present with recurrent bilioptysis, and in the chronic stage, develops bronchiectasis of the affected segment of the lung. Conservative treatment is directed at non-surgical approaches of relieving biliary obstruction to allow for normal flow of bile into the duodenum via endoscopy or percutaneous routes. However in complicated cases which failed conservative non-surgical therapy, surgical intervention is usually required. We report a 29-year-old Malay man who presented with chronic bilioptysis from a bronchobiliary fistula resulting from occlusion of a biliary stent inserted to treat intrahepatic biliary strictures. This was successfully treated surgically with a right medial lobectomy and interposition of a piece of viable tissue between the fistula stump on the dome of the diaphragm and the remaining lung.

Treating leukemia in a resource poor setting

Acute lymphatic leukemia (ALL) is the commonest childhood malignancy in India; most patients have no access to specialized health care. Our experience in treating such children who are unable to avail of facilities at specialized centers is described here. The case records of 79 patients with acute lymphatic leukemia, treated at a Government Medical College in Kerala over 15 years were analyzed. Of the 73 patients who completed treatment, 23 survived (36%) 20 had event-free survival more than 5 years after remission. The utilization of available resources is described. We suggest twinning between specialized centers in India and peripheral hospitals as a means to reach more children.

Long-term persistence of Coxiella burnetii after acute primary Q fever

BACKGROUND

Long-term persistence of C. burnetii in infected animals was established in the 1950s and 60s, but the implications for human Q fever are not fully explored.

AIM

To compare the prevalence of markers of infection in a cohort of Q fever patients in Australia (up to 5 years after infection) with those in the 1989 Birmingham cohort (12 years after infection).

DESIGN

Case follow-up study.

METHODS

C. burnetii was tested for by: (i) antibodies to Phase 1 and 2 antigens in the three immunoglobulin classes; (ii) detection of DNA in bone marrow and peripheral blood mononuclear cells by PCR assays directed against several different targets in the genome; and (iii) attempts to isolate coxiellas in cell culture or mice from PCR-positive samples. Amplicon specificity was verified by fluorometric probing and by sequencing. Cross-contamination was excluded by extensive use of non-template controls, and in particular by the use of certain IS1111a target sequences.

RESULTS

Irrespective of clinical state, both groups remained seropositive, principally exhibiting medium levels of IgG antibody against C. burnetii Phase 2 antigen. C. burnetii genomic DNA was detected by PCR in 65% of bone marrow aspirates from Australian patients and approximately 88% of Birmingham patients. No coxiella were isolated from PCR positive samples.

DISCUSSION

We propose a provisional model for persistence. In Q fever without sequelae, the process is largely confined to the bone marrow. In Q fever fatigue syndrome (QFS), it is modulated by the patient's immunogenetic background to give higher levels of coxiella genomes in bone marrow and increased shedding into the peripheral blood. In Q fever endocarditis, late pregnancy, or during iatrogenic or other immunosuppression, the multiplication cycle is prolonged, and a potential source of live organisms.

An intervention technique for children with autistic spectrum disorder: joint attentional routines

Virtually all children with autism are deficient in joint attentional skills. The impact of this deficit may be understood in the context of pragmatically based explanations of language acquisition. In this view, each step in the ontongeny of joint attention is consequential for language development. Thus, it is important that speech-language pathologists understand the developmental course of joint attention so that intervention may start at the earliest step possible. In this article, we review the literature on joint attention and its relationship with other rule systems of language. We discuss the ontogeny of joint attention in typical children. Finally, we describe the developmental course of joint attention as a framework for language intervention through the study of one case.

Knowledge of disease and dietary compliance in patients with end-stage renal disease

Noncompliance is a common problem in patients with end-stage renal disease. In this study, we assessed the relationship between knowledge of disease and dietary compliance in a cohort of 56 dialysis patients. Based on a health belief model of adherence, we predicted that dialysis patients who knew more about kidney disease and its treatment would be more complaint than those who knew less about these matters. We also examined the relationship between dietary compliance and patients' emotional well-being. We used a composite measure of compliance consisting of serum K, P, and interdialytic weight gain. A 30-item "Kidney Disease Questionnaire" was used to assess patients' knowledge of their illness. Contrary to prediction, compliers did not score higher on the knowledge questionnaire; in fact, the observed correlation of .32 was in the opposite direction. In the same vein, we found no relationship between compliance and emotional well-being. These results, although somewhat surprising, add to a growing body of research which indicates that medical compliance involves more than educating patients about the mechanisms and treatment of their illness.

Changes in nuclear localization of An3, a RNA helicase, during oogenesis and embryogenesis in Xenopus laevis

The immunolocalization of An3 protein, an ATP-dependent RNA helicase and a member of the DEAD box family, was compared with the localization of fibrillarin, a protein essential for rRNA processing, and snRNPs, which are involved in mRNA splicing reactions, during oogenesis and embryogenesis in Xenopus laevis. Although An3 protein was detected in the cytoplasm of all stages of oocytes, in most stages An3 protein was also present in the nucleus. Prior to stage I An3 protein was uniformly dispersed throughout the entire germinal vesicle; from stages I to V it was in nucleoli. By stage VI nucleolar labeling with anti-An3 disappeared and the protein was no longer present within nuclei. An3 reactivity was also present throughout the nuclei of follicle cells surrounding prestage I to stage VI oocytes. Both cytoplasmic and nuclear An3 staining were present in cells of stages 8 to 35 embryos; however, nuclear staining was punctate and uniformly distributed throughout the nucleoplasm. Fibrillarin was diffusely distributed throughout the entire germinal vesicle prior to stage I, localized exclusively to nucleoli of oocytes between stages I and VI and in nucleoli of stages 12 and 35 embryonic cells. Reactivity for snRNPs (anti-Sm) in germinal vesicles of prestage I oocytes was diffuse, and similar to the distribution of An3 and fibrillarin; in later stage oocytes anti-Sm staining was restricted to a population of granules, much fewer in number and more heterogeneous in size than nucleoli. Anti-Sm activity was apparent in nuclei of embryonic cells of stages 8 to 35 embryos. Although colocalization of the Sm epitope and An3 was not observed in developing oocytes and in embryonic cells, Sm reactive material was frequently found in close association with An3-positive nucleoli (oocytes) and nuclear deposits (embryonic cells). In stage IV and V oocytes treated with actinomycin D (4 micrograms/ml) to inhibit rRNA synthesis, nucleoli, which continued to possess fibrillarin, lacked An3; staining of follicle cell nuclei for An3 was unchanged. Treatment with 200 micrograms/ml actinomycin D to block mRNA synthesis, inhibited An3 but not fibrillarin staining in nuclei of prestage I oocytes and follicle cells. The changing patterns of An3 reactivity and the differential effects of actinomycin D on such localizations observed here are consistent with a role for An3 in the processing/production of RNA.

Amplification of antibody production by phosphorothioate oligodeoxynucleotides

A phosphorothioate oligodeoxynucleotide that is complementary (antisense) to the initiation region of the rev gene of HIV-1 causes hypergammaglobulinemia and splenomegaly in mice, and it induces B cell proliferation and differentiation in mouse spleen mononuclear cells (SMNCs) and human peripheral blood mononuclear cells in vitro. The current studies were performed to investigate the specificity of these immunomodulatory effects. Both the sense and antisense rev oligomers stimulated tritiated thymidine incorporation and secretion of immunoglobulin M (IgM) and immunoglobulin G (IgG) by mouse SMNCs in a concentration-dependent fashion, but the antisense oligomer produced greater immune effects. Studies comparing phosphorothioate oligomers (anti-rev, c-myc, and c-myb) either methylated or unmethylated at CpG dinucleotides showed that methylation effectively abrogated the proliferative effect and tended to reduce the immunoglobulin secretory activity, but the latter was not statistically significant except in the case of IgG in anti-rev oligomer-treated cultures. Mice were injected with the sense or antisense rev oligomers singly or in combination. The animals then were immunized with tetanus toxoid and received a booster 21 days later. Oligodeoxynucleotide-treated mice had significantly higher levels of IgM antibodies on days 28 and 35 and of IgG antibodies on days 14 and 35 as compared with mice that were immunized but received vehicle alone. There was no evidence for additive, synergistic, or antagonistic interactions of the sense and antisense rev oligomers. These results indicate that the unmethylated anti-rev oligomer is the most potent of the phosphorothioate oligomers tested at activating lymphocyte proliferation and differentiation and that a single intravenous injection of this oligodeoxynucleotide augments antibody production to a specific antigen as long as 35 days later.

Persistent pain associated with long-term intrathecal morphine administration

A 32-year-old man with chronic intractable right lower extremity pain unresponsive to multiple neurosurgical and pharmacologic treatments, including intrathecal morphine administration, was successfully treated with sciatic nerve block, discontinuance of opioid therapy, and psychologic interventions. Plasma and urine ratios of morphine metabolites morphine-3-glucuronide and morphine-6-glucuronide were analyzed at the beginning of our interventions, and the results indicated that morphine-3-glucuronide levels were significantly higher than morphine-6-glucuronide levels. The possible association between the observed morphine metabolite ratio and the intractable pain in patients resistant to opioids may have potential clinical implications.

Activin at parturition: changes of maternal serum levels and evidence for binding sites in placenta and fetal membranes

OBJECTIVE

To evaluate maternal serum activin A levels in pregnant women at parturition, correlated to the mode of delivery, and to localize activin receptor messenger RNA in human placenta and fetal membranes.

METHODS

A specific two-site enzyme-linked immunosorbent assay (ELISA) was used to measure maternal activin A levels. Activin receptor mRNA was localized in placenta and fetal membranes by in situ hybridization, using ActRII or ActRIIB antisense riboprobes.

RESULTS

Serum activin A levels increased significantly in pregnant women during vaginal or cesarean delivery after spontaneous labor. No significant changes of serum activin A were found in patients undergoing elective cesarean delivery. Syncytiotrophoblast and amnion cells hybridized to radiolabeled ActRIIB probe, whereas few cells within the structure of the villi and decidual cells hybridized to radiolabeled ActRII probe.

CONCLUSION

The present studies indicate that vaginal or cesarean delivery following spontaneous labor is characterized by increased activin A levels and that activin receptors are present on trophoblast and fetal membranes.

An3 mRNA encodes an RNA helicase that colocalizes with nucleoli in Xenopus oocytes in a stage-specific manner

An3 is a maternal mRNA localized to the animal hemisphere of oocytes and early embryos. We have analyzed the enzymatic activity and the subcellular localization of the protein encoded by An3 mRNA during Xenopus oogenesis. Antibodies raised using recombinant full-length and truncated An3 protein recognized a single protein in Xenopus and single proteins from HeLa cells, Drosophila, mouse testes, and Saccharomyces cerevisiae. An3 protein immunoprecipitated from stage IV and stage VI oocytes had ATP-dependent RNA helicase activity. The subcellular location of An3 protein changed during oocyte development. In previtellogenic oocytes, An3 was present throughout the nucleus; cytoplasmic localization was relatively sparse. Nuclear localization in mid-vitellogenic oocytes was primarily nucleolar; cytoplasmic staining increased relative to earlier stages. In stage VI oocytes, An3 protein was detected only in the cytoplasm. The temporal change in An3 protein localization is consistent with a role in the production of large maternal pools of rRNA during oogenesis.

Sperm nuclear transformations in cytoplasmic extracts from surf clam (Spisula solidissima) oocytes

Following their incorporation into oocytes, sperm nuclei (SN) of the surf clam, Spisula solidissima, undergo an initial expansion, followed by condensation and then a dramatic enlargement during their development into male pronuclei. These changes are temporally correlated with alterations in the maternal chromatin: germinal vesicle breakdown (GVBD), meiotic maturation, and female pronuclear development, respectively. To analyze possible changes occurring in SN at fertilization, surf clam oocyte extracts, prepared before and after parthenogenetic activation, were examined for their ability to affect SN in vitro. Sperm heads were incubated in extracts for variable periods up to 5 hr. Extracts prepared from oocytes following GVBD (15 min postactivation) induced an expansion in approximately 90% of SN by 60 min incubation. However, when SN were incubated in extracts from unactivated or 4-min-activated oocytes only approximately 30% underwent expansion. Ultrastructural examination of specimens taken at increasing periods of incubation in oocyte extracts revealed that SN expansion in vitro resembled chromatin decondensation in vivo. SN incubated 1 to 5 hr in extracts prepared from oocytes following GVBD consisted of decondensed chromatin surrounded to varying degrees by membranous cisternae. Staining with anti-lamin antibody was variable: some specimens (60-70%) were positive while others (30-40%) were weak to negative. In contrast, all decondensed SN incubated in extracts from postmeiotic oocytes (65 min postactivation) were delimited by an intact nuclear envelope possessing nuclear pores and reactive to anti-lamin antibody. Decondensation of SN in 15- or 65-min extracts was blocked by EDTA, 2,6-dimethyl-ami-nopurine, histone, and protamine. The presence (65-min extract) and absence (unactivated, 4- and 15-min extracts) of sperm nuclear envelope assembly in vitro is consistent with events in vivo, where such a structure forms after meiotic maturation in concert with the development of the female pronucleus.

Presence of inositol 1,4,5-trisphosphate receptor, calreticulin, and calsequestrin in eggs of sea urchins and Xenopus laevis

The presence of inositol 1,4,5-triphosphate receptor (InsP3R), calreticulin, and calsequestrin was demonstrated in eggs of sea urchins (Lytechinus pictus, Lytechinus variegatus, and Strongylocentroutus purpuratus) and Xenopus laevis. Binding of inositol 1,4,5-trisphosphate (InsP3) to microsomes of L. pictus eggs was inhibited by heparin and NaCl. An affinity-purified antibody against the C-terminal of the type I InsP3R, which recognizes InsP3R isoforms of rabbit brain (273 kDa) and Xenopus oocytes and eggs (256 kDa), reacted with a 373-kDa protein in sea urchin eggs. The 373-kDa protein was tentatively identified as the sea urchin egg InsP3R. Observations with fluorescence microscopy indicated that the InsP3R is present throughout the cytoplasm of sea urchin eggs in a pattern consistent with the distribution of endoplasmic reticulum. Small differences in the relative amount of reaction deposits in cortex vs subcortex were noted among the species of sea urchins examined. Reaction product was also localized to the periphery of female pronuclei in eggs of all three sea urchins. InsP3R reactivity was present in the perinuclear region, along the periphery of the germinal vesicle, and throughout the animal and vegetal hemispheres of Xenopus oocytes. A similar cytoplasmic staining pattern was also observed in eggs, although islands of reactivity, much larger than those in oocytes, were present in the animal hemisphere of eggs. Calreticulin and calsequestrin in sea urchin eggs had the same molecular mass as in rabbit brain (56 and 60 kDa, respectively), but differed from those present in Xenopus oocytes/eggs (61 and 57 kDa, respectively). The distribution of calreticulin and calsequestrin in both sea urchin and Xenopus oocytes and eggs was similar to that observed for the InsP3R. These results are discussed in relation to previous studies of Ca2+ regulation during egg development and fertilization and suggest that in the oocytes and eggs of the species examined, InsP3-sensitive Ca2+ stores play an important role in the regulation of cellular Ca2+.

Infrared laser diode irradiation has no behavioral or biochemical effect on pain in the sciatic nerve ligation-induced mononeuropathy in rat

The aim of this study was to evaluate the effect of acute and repeated (5 days) treatment with various types of infrared (IR) diode lasers and probes (single- vs cluster-beam) on the pain response in rats with peripheral mononeuropathy produced by sciatic nerve ligation. Male Sprague-Dawley rats were anesthetized with sodium pentobarbital, and the mid-thigh was surgically exposed to reveal the sciatic nerve, around which four ligatures were loosely tied. On postoperative day 5, the skin over the sciatic nerve lesion was subjected to a 30-min daily local exposure from a 904-nm IR diode laser (700 Hz, average output power 10 mW) with a single-beam probe, a 830-nm IR diode laser (700 Hz) with either a single-beam (average output power 50 mW) or cluster-beam probe (average output power 15 mW), or placebo for 5 consecutive days. Two pain responses (foot-withdrawal time and the hind-paw elevation time) were measured on both sides using the radiant heat method on days 5 and 9. In addition, cold allodynia was measured on day 9 of treatment by placing the rats on a chilled metal plate (4 degrees C) and measuring the duration of elevation of either of the hind paws. On day 9, the animals were sacrificed for collection of the samples of brain and lumbar spinal cord for the determination of the tissue concentrations of dynorphin A1-8-like immunoactivity (DYN) using specific radioimmunoassay (RIA). The hind-paw withdrawal and elevation times on the right side in all groups subjected to the various methods of IR laser irradiation did not differ significantly as compared with the placebo-treated group when measured on days 5 and 9 after surgery. No statistically significant differences in withdrawal response and elevation time of the unaffected left hind paw were noted either. The measurement of cold allodynia similarly failed to reveal any effect in laser-treated groups versus placebo. The RIA analysis found that tissue concentrations of DYN were significantly elevated in the spinal cord ipsilaterally to the ligation side, as compared with the contralateral side, in all rats with sciatic nerve ligation. All modalities of IR diode laser treatment did not produce any significant difference in the brain and spinal cord level of DYN on postoperative day 9 in all treatment groups. It is concluded that repeated IR diode laser treatment did not reduce hyperalgesia induced by sciatic nerve ligation in rats.

Morphogenesis of Maternal and Paternal Genomes in Fertilized Oyster Eggs (Crassostrea gigas): Effects of Cytochalasin B at Different Periods During Meiotic Maturation

Fertilized oyster (Crassostrea gigas) eggs, treated with and without cytochalasin B (CB) at varying periods during meiotic maturation, were examined following 7-aminoactinomycin D (7-AAD) and anti-{beta} tubulin staining for DNA and microtubular patterns, respectively. Electron microscopic observations of untreated fertilized eggs revealed the development of an extensive network of endoplasmic reticulum during germinal vesicle breakdown. Germinal vesicle breakdown was not accompanied by the disappearance of the nucleolus; the latter persisted morphologically unchanged throughout fertilization. The first meiotic spindle [12.4 +/- 1.0 {mu}m (1) x 5.4 +/- 0.55 {mu}m (diameter (d); metaphase plate)] was oriented with its long axis perpendicular to the egg's surface. In contrast, the second meiotic spindle was approximately one half the size of the first [7.4 +/- 0.65 {mu}m (1) x 2.91 +/- 0.29 {mu}m (d)] and initially oriented with its long axis parallel to the egg's surface. Just prior to anaphase II, the spindle rotated so that its long axis became perpendicular to the egg's surface. Following its incorporation into the egg cytoplasm, the sperm nucleus dispersed but did not form a nuclear envelope until the completion of polar body formation. Just prior to pronuclear migration, an array of microtubules assembled around the female pronucleus, and then regressed; concomitantly, a sperm aster formed in conjunction with the centrosome associated with the developing male pronucleus. Following their migration and apposition with one another, both pronuclei underwent prophase as independent structures. Chromosomes from the male and female pronuclei became organized on a mitotic spindle in preparation for first cleavage. In zygotes treated with CB continuously or for just meiosis I, anaphase I occurred; however, a polar body failed to form. Consequently, all the diads were retained within the zygote and became situated on a tripolar spindle. In such cases, anaphase II resulted in the production of a variable number of chromosomal aggregations that developed into pronuclei (3 to 6). In contrast, zygotes treated with CB during meiosis II developed spindles characteristic of untreated specimens; however, polar body formation was blocked, resulting in the development of usually two maternal pronuclei. Morphogenesis of C. gigas fertilized eggs is discussed in reference to similar processes in other species and with respect to strategies of triploid embryo production using CB.

Immune stimulation by an antisense oligomer complementary to the rev gene of HIV-1

Mice developed massive splenomegaly and polyclonal hypergammaglobulinemia within 2 days after intravenous injection of a phosphorothioate oligomer that is antisense to a portion of the rev region of the HIV-1 genome. Histologic examination of spleens from injected animals showed marked expansion of a uniform-appearing population of small lymphocytes and many mitoses. Spleen mononuclear cells (SMNCs) from injected animals showed approximately a 10-fold-increased uptake of [3H]thymidine and production of IgM and IgG. Flow cytometry analysis indicated that the responding cells were predominantly B-lymphocytes. The anti-rev oligomer also was mitogenic in vitro and stimulated immunoglobulin production by normal mouse SMNCs and human peripheral blood mononuclear cells. Similar immunologic effects were observed with an anti-rev 21-mer phosphorothioate, truncated at the 3' end, but not with a 20-mer human p53 antisense phosphorothioate or a 28-mer anti-rev phosphodiester. These observations are consistent with the possibility that DNA sequences homologous to the rev gene participate in the regulation of mammalian lymphocyte activation, proliferation and maturation.

Cortical localization of a calcium release channel in sea urchin eggs

We have used an antibody against the ryanodine receptor/calcium release channel of skeletal muscle sarcoplasmic reticulum to localize a calcium release channel in sea urchin eggs. The calcium release channel is present in less than 20% of immature oocytes, where it does not demonstrate a specific cytoplasmic localization, while it is confined to the cortex of all mature eggs examined. This is in contrast to the cortical and subcortical localization of calsequestrin in mature and immature eggs. Immunolocalization of the calcium release channel reveals a cortical reticulum or honeycomb staining network that surrounds cortical granules and is associated with the plasma membrane. The network consists of some immunoreactive electron-dense material coating small vesicles and elongate cisternae of the endoplasmic reticulum. The fluorescent reticular staining pattern is lost when egg cortices are treated with agents known to affect sarcoplasmic reticulum calcium release and induce cortical granule exocytosis (ryanodine, calcium, A-23187, and caffeine). An approximately 380-kD protein of sea urchin egg cortices is identified by immunoblot analysis with the ryanodine receptor antibody. These results demonstrate: (a) the presence of a ryanodine-sensitive calcium release channel that is located within the sea urchin egg cortex; (b) an altered calcium release channel staining pattern as a result of treatments that initiate the cortical granule reaction; and (c) a spatial and functional dichotomy of the ER which may be important in serving different roles in the mobilization of calcium at fertilization.

Nascent protein requirement for completion of meiotic maturation and pronuclear development: examination of fertilized and A-23187-activated surf clam (Spisula solidissima) eggs

The involvement of newly synthesized proteins and calcium in meiotic processes, sperm nuclear transformations, and pronuclear development was examined in emetine-treated, fertilized, and A-23187-activated Spisula eggs by observing changes in the morphogenesis of the maternal and paternal chromatin. Emetine treatment (50 micrograms/ml) initiated 30 min before fertilization or A-23187 activation inhibited incorporation of [3H]leucine into TCA-precipitable material and blocked second polar body formation. Sperm incorporation and the initial enlargement of the sperm nucleus were unaffected; however, the dramatic enlargement and transformation of the sperm nucleus into a male pronucleus, which normally follow polar body formation, were delayed 10 to 20 min. Unlike the situation in untreated, control eggs, male pronuclear development took place while the maternally derived chromosomes remained condensed. It was not until approximately 20 min after the normal period of pronuclear development that the maternal chromosomes dispersed and formed a female pronucleus in emetine-treated, fertilized eggs. Formation of pronuclei, however, was unaffected in both emetine-treated, A-23187-activated eggs and fertilized eggs incubated with A-23187. These observations indicate that germinal vesicle breakdown, first polar body formation, and initial transformations of the sperm nucleus are independent of newly synthesized proteins. Inhibition of second polar body formation and the delay in pronuclear development brought about by emetine, as well as the appearance of silver grains over pronuclei in autoradiographs of control eggs incubated with [3H]leucine demonstrate that nascent proteins are involved with the completion of meiotic maturation and the development of male and female pronuclei. The ability of A-23187 to override the inhibitory effects of emetine on pronuclear development suggests that both nascent protein and calcium signals are involved in regulating the status of the maternal and paternal chromatin during pronuclear development.

Pronuclear formation in starfish eggs inseminated at different stages of meiotic maturation: correlation of sperm nuclear transformations and activity of the maternal chromatin

Changes in sperm nuclei incorporated into starfish, Asterina miniata, eggs inseminated at different stages of meiosis have been correlated with the progression of meiotic maturation. A single, uniform rate of sperm expansion characterized eggs inseminated at the completion of meiosis. In oocytes inseminated at metaphase I and II the sperm nucleus underwent an initial expansion at a rate comparable to that seen in eggs inseminated at the pronuclear stage. However, in oocytes inseminated at metaphase I, the sperm nucleus ceased expanding by meiosis II and condensed into chromosomes which persisted until the completion of meiotic maturation. Concomitant with the formation and expansion of the female pronucleus, sperm chromatin of oocytes inseminated at metaphase I enlarged and developed into male pronuclei. Condensation of the initially expanded sperm nucleus in oocytes inseminated at metaphase II was not observed. Instead, the enlarged sperm nucleus underwent a dramatic increase in expansion commensurate with that taking place with the maternal chromatin to form a female pronucleus. Fusion of the relatively large female pronucleus and a much smaller male pronucleus was observed in eggs fertilized at the completion of meiotic maturation. In oocytes inseminated at metaphase I and II, the male and female pronuclei, which were similar in size, migrated into juxtaposition, and as separate structures underwent prophase. The chromosomes in each pronucleus condensed, intermixed, and became aligned on the metaphase palate of the mitotic spindle in preparation for the first cleavage division. These observations demonstrate that the time of insemination with respect to the stage of meiotic maturation has a significant effect on sperm nuclear transformations and pronuclear morphogenesis.

Growth hormone regulation of the growth hormone receptor mRNA in cultured rat epiphyseal chondrocytes

This study was designed to investigate whether growth hormone (GH) influences the expression of its own receptor in chondrocytes. To investigate this possibility GH-receptor mRNA was measured in cultured rat epiphyseal chondrocytes in the absence or presence of GH under various experimental conditions. Chondrocytes were isolated enzymatically from epiphyseal growth plates of the proximal tibia of 20-day-old male rats and cultured in monolayer in Ham's F-12 medium supplemented with 10% calf serum and 1% of a serum substitute. The cells were seeded at various densities (100,000-1,000,000 cells per flask) and cultured for 14 days. Subsequently, the calf serum-containing medium and the cells cultured for various periods of time (0-24 h) before total nucleic acid preparation. GH-receptor mRNA was measured with a solution hybridization technique using [35S]UTP-labeled RNA growth hormone receptor cloned from rat liver cDNA. Human GH (hGH; 50 ng/ml) increased GH-receptor mRNA after 3 h and maximal levels were seen 12 h after GH addition. This effect of hGH was time and dose dependent with a significant effect of hGH at a concentration of 0.5 ng/ml and a maximal effect at 50 ng/ml. The hGH-stimulated increase of GH-receptor mRNA was completely blocked by actinomycin-C1 (1.0-0.1 micrograms/ml), while cycloheximide (10 micrograms/ml) only slightly counteracted the hGH effect. Rat and human GH were equally potent, and ovine prolactin was effective at 500 ng/ml but not 5 and 50 ng/ml. A high dose of insulin-like growth factor-I (IGF-I; 1 microgram/ml) caused a small stimulatory effect and addition of 10% calf serum caused a marked increase in GH-receptor mRNA. The level of GH receptor mRNA after 14 days of culture was inversely proportional to the cell density at the start of culture. These results show that GH specifically regulates mRNA levels for its own receptor in rat epiphyseal chondrocytes by interacting with somatogenic binding sites. These findings also suggest a transcription-dependent regulatory system between the GH-receptor and the GH-receptor gene.

Metabolic epidemiology of colon cancer: fecal mutagens in healthy subjects from rural Kuopio and urban Helsinki, Finland

Fecal mutagenic activity and dietary pattern of rural and urban Finnish population groups with distinct risk for the development of colon cancer were studied in a low-risk population in rural Kuopio and an intermediate-risk population in urban Helsinki. The average daily intake of protein and fat was the same in the two groups but the frequency of consumption of whole-grain cereals and whole-grain bread, as well as the amount of fiber from the bread were higher in Kuopio as compared to Helsinki. Fecal samples collected for 2 days were incubated under anaerobic conditions at 37 degrees C for 96 h, extracted with hexane: peroxide-free diethyl ether, partially purified on a silica Sep-Pak cartridge, and assayed for mutagenic activity using the Salmonella typhimurium/mammalian microsome system. The fecal mutagenic activity was observed with the tester strains TA98 and TA100 with and without microsomal activation in both the population groups. The percentage of samples showing fecal mutagenic ratio greater than 3 with TA98 and TA100 with microsomal activation, was higher in volunteers from Helsinki than in Kuopio.

Effect of Japanese seaweed (Laminaria angustata) extracts on the mutagenicity of 7,12-dimethylbenz[a]anthracene, a breast carcinogen, and of 3,2'-dimethyl-4-aminobiphenyl, a colon and breast carcinogen

Animal model studies suggest that diets containing Laminaria angustata, a brown seaweed commonly eaten in Japan, inhibit breast carcinogenesis. In order to identify the compound(s) in the seaweed responsible for tumor-inhibiting activity, we used Ames/mammalian microsome assay system to determine the antimutagenic (or anticarcinogenic) effect of various solvents and water extracts of Laminaria angustata. The antimutagenic effects of acetone, ether, chloroform, chloroform + methanol, hot water and cold water extracts on the mutagenicity induced by 7,12-dimethylbenz[a]anthracene (DMBA), a breast carcinogen, and 3,2'-dimethyl-4-aminobiphenyl (DMAB), a colon and breast carcinogen, was studied using the Salmonella typhimurium strains TA98 and TA100. All extracts were nonmutagenic in both bacterial tester strains. The addition of 10-100 mg solvent extracts of seaweed/plate greatly inhibited DMAB-induced mutagenicity in both tester strains (80-96% inhibition) and DMBA-induced mutagenicity in TA100 (about 82%), whereas hot and cold water extracts produced a moderate inhibition in a dose-related manner in both strains.

Fecal mutagens from subjects consuming a mixed-western diet

Because of potential significance of fecal mutagens (presumptive carcinogens) in the pathogenesis of colon cancer, feces from 99 healthy subjects from the New York metropolitan area were studied. The diet histories indicate that all participants were consuming a mixed-western diet which is high in total fat and low in fiber. Fecal samples that were incubated under anaerobic conditions at 37 degrees C for 96 h or frozen without incubation, were extracted with hexane: peroxide-free diethyl ether (1:1), partially purified on a silica Sep-pak cartridge and assayed for mutagenicity using the Salmonella typhimurium/mammalian microsome system. Aliquots of fecal samples incubated anaerobically showed a higher frequency of mutagenic activity (per cent samples showing activity) in strains TA98 and TA100 with and without microsomal (S9) activation. In addition, the mutagens requiring S9 activation, were more frequently inactivated when the fecal samples were frozen immediately after defecation and transported to the laboratory. Compared with hexane: ether, extraction of fecal samples with acetone increased the mutagenic activity mostly with TA98 with S9 activation. The HPLC fractionation of hexane: ether extract with methanol: water gradient using reverse phase C-18 column and UV detector at 254 nm indicated that the mutagenic activity (TA98 with S9 activation) is concentrated in several peaks. This is the first demonstration of HPLC profile of fecal samples that are active in TA98 with S9 activation. HPLC profile of fecal extracts and mutagenic activity of these extracts in strains TA98 and TA100 suggest the presence of several types of mutagens in the feces of healthy subjects consuming a high-fat, low-fiber mixed-western diet.

Effect of micronutrients, antioxidants and related compounds on the mutagenicity of 3,2'-dimethyl-4-aminobiphenyl, a colon and breast carcinogen

The possible antimutagenic effects of butylated hydroxytoluene (BHT), ethoxyquin, disulfiram, indole-3-carbinol, indole-3-acetonitrile, sodium selenite and alpha-tocopherol on 3,2'-dimethyl-4-aminobiphenyl-induced mutagenicity were studied using the Ames Salmonella/mammalian microsome assay system with strains TA98 and TA100. All seven compounds were nonmutagenic in both bacterial tester strains. The addition of or 50-250 micrograms of sodium selenite, 5-50 mg of alpha-tocopherol or 50-250 microgram of BHT per plate inhibited DMAB-induced mutagenicity in TA98 and/or TA100. Ethoxyquin, disulfiram and indole-3-carbinol increased DMAB-induced mutagenicity in TA100, whereas these compounds had little or no effect in TA98-3-acetonitrile had very little effect in either strain.

Effect of butylated hydroxytoluene and butylated hydroxyanisole on the mutagenicity of 3,2'-dimethyl-4-aminobiphenyl

This study was undertaken to investigate the possible antimutagenic effects of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on 3,2'-dimethyl-4-aminobiphenyl (DMAB)-induced mutagenicity, using the Ames Salmonella/mammalian microsome system. The addition of 100-250 micrograms of BHT or 25-500 micrograms of BHA/plate was found to inhibit DMAB-induced mutagenicity in Salmonella strains TA 98 and TA 100. In TA 100, the mutagenicity was further inhibited with the addition of S9 prepared from the livers of rats fed a 0.6% BHT diet as compared to S9 from the animals fed a diet containing no BHT.

Fecal sterols and bacterial beta-glucuronidase activity: a preliminary metabolic epidemiology study of healthy volunteers from Umea, Sweden, and metropolitan New York

The dietary pattern, fecal bile acid and neutral sterol concentrations, and the bacterial beta-glucuronidase activity of 2 population groups with a varied risk for colon cancer development (i.e., a high-risk population in the metropolitan New York area and an intermediate-risk population in Umea, Sweden) were investigated. The average daily intake of dietary protein was the same in the 2 groups, but the fat intake was higher in Umea than in New York. The daily total fiber intake was also higher in Umea, as was the daily total stool output. The concentration of fecal secondary bile acids and beta-glucuronidase activity was lower in Umea than in New York, but the total daily excretion of these constituents was the same in both groups. The data suggest that one of the factors contributing to the lower risk of colon cancer in Umea, despite the high dietary fat intake, is the high intake of dietary whole grain and cereal fiber, which leads to an increase in stool bulk, thus diluting and/or binding promoters.

Effect of high-fat, high-beef diet and of mode of cooking of beef in the diet on fecal bacterial enzymes and fecal bile acids and neutral sterols

The effect of a high-fat, high-beef diet and of method of preparation of beef in the diet on the fecal bile acids and neutral sterols and on the activities of fecal bacterial beta-glucuronidase, cholesterol dehydrogenase and 7 alpha-dehydroxylase was studied in healthy men and women, 24-41 years old, who were consuming a customary mixed-western diet. The experimental diets were high in fat and beef, which was cooked rare, medium or well-done. The sequence of dietary regimen was selected at random and each diet phase lasted for 4 weeks. Individual 24-hour fecal specimens were collected from each volunteer for the final 3 days during each dietary period, including pre- and post-experimental periods while they were consuming a customary mixed-western diet. The mode of cooking beef in the high-fat, high-beef experimental diets had no influence on the fat and protein content of the diets but the fat content of experimental diets was high compared to customary mixed-western diet. Fecal bacterial beta-glucuronidase activity and fecal secondary bile acid and cholesterol metabolite levels were significantly higher during the experimental diet periods but the fecal bacterial activities of 7 alpha-dehydroxylase and cholesterol dehydrogenase were unaffected. The mode of cooking beef in experimental diets had no influence on the fecal bacterial enzymes and on the excretion of fecal bile acids and cholesterol metabolites.