Postpartum depression and thyroid antibody status

It has long been known that primary thyroid disorder is associated with mood disorder and vice versa so that the features of major depression can occur in individuals with hypothyroidism. Also, primary depression is often associated with disturbance of the hypothalamic-pituitary-thyroid axis. Roberton's historic description of the relatively common occurrence of postpartum hyperthyroidism eventually led to the discovery that thyroid antibody-positive women are prone to hypothyroidism, which is often preceded by transient hyperthyroidism after delivery. Various aspects of depression and the association with thyroid antibody status are described and the importance of treatment and management of the condition emphasized, particularly in view of the risk of later permanent hypothyroidism in mothers. The effects of associated mood disorder on attachment to the baby, the family, and later development of the child are also described.

Exploiting antibody-based technologies to manage environmental pollution

Many commodities used in the food, cosmetic, chemical and environmental industrial sectors function by binding to other molecules. Antibodies can bind virtually any molecule, from large proteins to small organic ligands, and could replace substances with undesirable medical, social or environmental side effects, if they could be provided in stable configurations and in quantities and at costs acceptable to industry. Antibody fragments also offer the possibility of sensitive detection and efficient removal of organic pollutants from the environment.

Antioxidants protect against reactive oxygen species associated with adriamycin-treated cardiomyocytes

Adriamycin (ADM) is a broad-spectrum antineoplastic antibiotic used to treat cancer patients. However, the usefulness of this drug is presently limited by the development of a dose-dependent cardiotoxicity. A current hypothesis for the ADM-induced cardiotoxicity is the production of reactive oxygen radicals by the drug. We utilized the fluorescent indicator 2',7'-dichlorodihydrofluorescein diacetate (DCFH/DA), in which fluorescence appears if reactive oxygen species (ROS) are present, to investigate the ability of ADM to generate reactive oxygen species and the potential protective effect of antioxidants in a cultured cardiomyocyte model. All three of the antioxidants (alpha-phenyl-tert-butyl nitrone (PBN), trolox, and 5-aminosalicylic acid (5-ASA)) tested in our ADM-treated myocytes provided protection against the oxidative stress induced by the drug. These findings suggest that antioxidants modulate ADM-induced oxidative stress, and they are discussed in terms of a possible therapeutic strategy in the prevention of cardiotoxicity resulting from ADM administration.

Household, family and welfare: past, present and future

J. Robin, From childhood to middle age: cohort analysis in Colyton, 1851–1891. (Cambridge: Cambridge Group for the History of Population and Social Structure, Working Paper Series, no. 1, n.d.). Pages iv+83. £2.50.

H. Cunningham and P. P. Viazzo (eds.), Child labour in historical perspective, 1800–1985: case studies from Europe, Japan and Colombia. (Florence: United Nations Children's Fund, International Child Development Centre, 1996.) Pages 105. US$9.00.

L. Marks, Metropolitan maternity: maternal and infant welfare services in early-twentieth century London. (Amsterdam: Rodopi, 1996.) Pages xxii+344.

A. Walker (ed.), The new generational contract: intergenerational relations, old age and welfare. (London: UCL Press, 1996). Pages xiii+241.

These four publications vary significantly in their geographical coverage and general subject matter, but it is still possible to identify a number of common themes. They are particularly important for what they reveal about the links between formal welfare provision, protective legislation, family care, and the standard of living. They also yield many individual insights into such matters as family reconstitution, migration, child labour, working conditions, municipal welfare services, the decline of infant and maternal mortality, and the possible existence of a demographic threat to the viability of modern welfare states.

Approximate reliability of genetic evaluations under an animal model

A method was developed for calculating approximate reliability for national systems of evaluation. The method combined the reliability of three information sources: parent average, animal's own records, and progeny records. This method provided good approximation to the actual values with minimal upward bias and was considerably better than the current national method of New Zealand genetic evaluation or Meyer's method for all accuracy measures. Our method had an average absolute bias of 0.006 compared with 0.026 and 0.035 for the current national method and Meyer's method, respectively. Our method was less computationally demanding than the current New Zealand method. One of the major advantages of the method is that it can be extended to accommodate more complex models by altering the selection index equations within the method. An example is given for which the method was extended to account for a genetic correlation other than unity between an incomplete lactation and a complete lactation yield.

A comparison of the performance of rating scales used in the diagnosis of postnatal depression

The results of a study looking into the association between thyroid status and depression in the postpartum period were reanalysed to explore the psychometric properties of the rating scales employed. The performance of the Edinburgh Postnatal Depression Scale was found to be superior to that of the Hospital Anxiety and Depression Scale in identifying RDC-defined depression, and on a par with the observer-rated Hamilton Rating Scale for Depression, which it also matched for sensitivity to change in mood state over time. The anxiety subscale of the Hospital Anxiety and Depression Scale performed well, reflecting the fact that anxiety represents a prominent symptom in postnatal depression.

Synthesis and evaluation of analogues of the partial agonist 6-(propyloxy)-4-(methoxymethyl)-beta-carboline-3-carboxylic acid ethyl ester (6-PBC) and the full agonist 6-(benzyloxy)-4-(methoxymethyl)-beta-carboline-3-carboxylic acid ethyl ester (Zk 93423) at wild type and recombinant GABAA receptors

A pharmacophore and an alignment rule have previously been reported for BzR agonist ligands. The design and synthesis of 6-(propyloxy)-4-(methoxymethyl)-beta-carboline-3-carboxylic acid ethyl ester (6-PBC, 24, IC50 = 8.1 nM) was based on this pharmacophore. When evaluated in vivo this ligand exhibited anticonvulsant/anxiolytic activity but was devoid of the muscle relaxant/ataxic effects of "classical" 1,4-benzodiazepines (i.e., diazepam). Significantly, 6-PBC 24 also reversed diazepam-induced muscle relaxation in mice. The 3-substituted analogues 40-46 and 48 of 6-PBC 24 and Zk 93423 27(IC50 = 1 nM) were synthesized and evaluated in vitro to determine what affect these modifications would have on the binding affinity at recombinant BzR subtypes. With the exception of the 3-amino ligands 40 and 41, all the beta-carbolines were found to exhibit high binding affinity at BzR sites. The 3-propyl ether derivative 45 was also evaluated in vivo and found to be devoid of any proconvulsant or anticonvulsant activity at doses up to 40 mg/kg. The 6-(1-naphthylmethyloxy) and 6-octyloxy analogues 25, 26, 28, and 29 of 6-PBC 24 were synthesized to further evaluate the proposed alignment of agonists vs inverse agonists in the pharmacophore of the BzR. In addition, ligands 26 and 29 were designed to probe the dimensions of lipophilic pocket L3 at the agonist site. The activity of 29 was evaluated in vivo; however, this analogue elicited no pharmacological effects at doses up to 80 mg/kg. These and other related beta-carbolines were also examined in five recombinant GABAA receptor subtypes. Ligands 52-61 all exhibited moderate to high affinity at GABAA receptors containing alpha1 subunits. These ligands will be useful in further defining the pharmacophore at alpha1 beta3 gamma2 receptors.

Mitochondrial oxidative function in human saponin-skinned muscle fibres: effects of prolonged exercise

1. The influence of prolonged exhaustive exercise on mitochondrial oxidative function was investigated in ten men. 2. Muscle biopsies were taken before and after exercise and mitochondrial respiration investigated in fibre bundles made permeable by pretreatment with saponin. 3. After exercise, respiration in the absence of ADP increased by 18 % (P < 0.01), but respiration at suboptimal ADP concentration (0.1 mM) and maximal ADP-stimulated respiration (1 mM ADP) remained unchanged. 4. In the presence of creatine (20 mM), mitochondrial affinity for ADP increased markedly and respiration at suboptimal ADP concentration (0.1 mM) was similar (pre-exercise) or higher (post-exercise; P < 0.05) than with 1 mM ADP alone. The increase in respiratory rate with creatine was correlated to the relative type I fibre area (r = 0.84). Creatine-stimulated respiration increased after prolonged exercise (P < 0.01). 5. The respiratory control index (6.8 +/- 0.4, mean +/- s.e.m.) and the ratio between respiration at 0.1 and 1 mM ADP (ADP sensitivity index, 0.63 +/- 0.03) were not changed after exercise. The sensitivity index was negatively correlated to the relative type I fibre area (r = -0.86). 6. The influence of exercise on muscle oxidative function has for the first time been investigated with the skinned-fibre technique. It is concluded that maximal mitochondrial oxidative power is intact or improved after prolonged exercise, while uncoupled respiration is increased. The latter finding may contribute to the elevated post-exercise oxygen consumption. The finding that the sensitivity of mitochondrial respiration for ADP and creatine are related to fibre-type composition indicates intrinsic differences in the control of mitochondrial respiration between fibres.

The development of general practice standards in Australia. Royal Australian College of General Practitioners

The Royal Australian College of General Practitioners has spent 4 years developing a set of entry standards which define the minimum features of general practices expected for the mid-1990s. The project design followed a slow, iterative process, with several opportunities for wide consultation with professional, consumer and Government groups. The draft standards were piloted in 25 volunteer practices, modified and then field-tested in 200 randomly selected practices representing urban and rural practices. Results of this field testing showed that the standards had content validity and that reliable measures were possible using triangulation from several data sources. The current version of the standards has been distributed widely for voluntary application in Australian general practices from early 1997.

The effect of microgravity on testicular androgen secretion

BACKGROUND

Spaceflight causes a number of physiological changes in the human body. Most would consider space travel to be a stressful event even for well-trained astronauts. Should this be true, pituitary gonadotrophins (mainly LH) and testicular androgens, like testosterone (T), should decrease inflight in male astronauts. We therefore hypothesized that lowered testicular androgen levels might occur in men during spaceflight, due to stress-dependent lowered LH concentrations.

METHODS

In order to test this hypothesis, on different day pre-, in- and postflight we assayed wake-time salivary and urinary T in four astronauts, as well as wake-time plasma levels of adrenocorticotropin (ACTH), cortisol (CS), LH, T and its peripherally active metabolite 3-alpha-diol glucuronide (3ADG). In order to compare clinical to subjective data, all 7 male crewmembers anonymously answered a daily questionnaire from pre- to postflight asking them to self-rate sexual drive and potency, muscle strength and mood.

RESULTS

Salivary, urinary and plasma T, as well as 3ADG, decreased during flight, while LH unexpectedly increased inflight (p < 0.05). A parallel decrease in sexual drive was observed (p < 0.05). A dramatic recovery of salivary T was found on R + 1.

CONCLUSIONS

This was the first time that spaceflight was demonstrated to cause temporary, still dramatic hypoandrogenism which was not due to blunted pituitary gonadotrophin secretion. The cause for hypoandrogenism is unknown but it may depend on fluid shift affecting testicular function or androgen distribution in various body compartments.

Fatal Erysipelothrix rhusiopathiae septicemia in a captive Pacific white-sided dolphin (Lagenorhyncus obliquidens)

One male of a group of seven Pacific white-sided dolphins (Lagenorhynchus obliquidens) died after a brief period of nonspecific clinical signs. Four beluga whales (Delphinapterus leucas) and four harbor seals (Phoca vitulina) were managed in the same water system. Gross examination of the dolphin revealed only moderately enlarged mesenteric lymph nodes. Histopathology revealed small to massive numbers of gram-positive bacilli, usually intravascular, in all tissues. Bacteria were both extracellular and present in macrophages, monocytes, and neutrophils. Aerobic bacterial culture of lung, liver, kidney, and spleen yielded pure cultures of Erysipelothrix rhusiopathiae. Based on clinical course, histopathology, and bacteriology, a diagnosis of acute erysipelas septicemia was made. None of the other cetaceans or pinnipeds exhibited clinical signs.

Synthesis of green fluorescent protein-ricin and monitoring of its intracellular trafficking

We performed genetic engineering to fuse enhanced green fluorescent protein (EGFP) to the N terminus of RTA, expressed the fusion protein in Escherichia coli, purified and reassociated EGFP-RTA with plant RTB, and purified EGFP-ricin by size exclusion HPLC. The fusion heterodimer was able to bind galactosides, intoxicate cells, and show strong fluorescence. Mammalian cells incubated with EGFP-ricin showed strong cell surface fluorescence at 4 degrees C and, on incubation at 37 degrees C, distributed initially to endosomes and then to Golgi vesicles. Variable sensitivity of mammalian cells to ricin and ricin fusion proteins may be due in part to different patterns of intracellular routing. Cells were incubated with ricin or EGFP-ricin, and inhibition of protein synthesis was measured. Human hepatocellular carcinoma Hep3B cells were 10-fold more sensitive to ricin and 85-fold more sensitive to EGFP-ricin than human epidermoid carcinoma KB cells. Epifluorescence microscopy of cells incubated with EGFP-ricin showed greater localization of the fluorescence signal in the Golgi compartments in Hep3B cells than in KB cells. These data support a model requiring a Golgi-dependent step in cell intoxication by ricin. The work further identifies the usefulness of green fluorescent protein fusions in the study of retrograde transport of internalized peptides.

Ricin fusion toxin targeted to the human granulocyte-macrophage colony stimulating factor receptor is selectively toxic to acute myeloid leukemia cells

Treatment failure of patients with acute myelogenous leukemia (AML) is frequently due to the development of multidrug resistance phenotype blasts. We have expressed a fusion protein consisting of human granulocyte-macrophage colony stimulating factor (GMCSF) fused to the N-terminus of a lectin-deficient ricin toxin B chain (RTB) in Spodoptera frugiperda insect cells. The fusion protein was purified by immunoaffinity chromatography and reassociated with chemically deglycosylated ricin toxin A chain (RTA). The resulting fusion toxin was found to react with antibodies to GMCSF, RTB and RTA and had the predicted molecular mass of 80 kDa. GMCSF-ricin bound poorly to asialofetuin (Kd = 10(6) M-1) and receptor negative cells indicating loss of lectin activity, but bound strongly to GMCSF receptor positive HL60 cells. Ligand displacement assays showed fusion toxin affinity 2.6-fold less than native GMCSF. Selective inhibition of protein synthesis was observed on receptor positive cells. Induction of apoptosis was also observed on receptor positive cells. Cells expressing multidrug resistance gene products (P-gp, Bcl2 and BclXL) were also sensitive to fusion toxin. These results suggest that GMCSF-ricin deserves further preclinical development.

Harlequin ichthyosis (ichq): a juvenile lethal mouse mutation with ichthyosiform dermatitis

The harlequin ichthyosis (ichq) mouse mutation arose spontaneously in 1989 in a colony of BALB/cJ mice at The Jackson Laboratory. Affected mice developed thick skin due to formation of compact, orthokeratotic scales that fractured over articular surfaces, secondary to bending. Harlequin ichthyosis mice on the inbred BALB/cJ background died between 9 and 12 days of age. Onset of the clinical phenotype corresponded with emergence of hair fibers from follicles at 5 days of age. There was marked proliferation of the root sheaths of anagen hair follicles, limited to the region within the dermis. Sebaceous glands were present but small compared with those of littermate controls. Emerging hair fibers were surrounded by a thick, compact sheath of cornified cells. Mutant skin contained large mitochondria with lamellar-shaped, electron-dense structures at the ultrastructural level. Keratohyalin granules were smaller and less pleomorphic than those in control mice. Lamellar bodies were not evident in either mutant or littermate control mice. Using a panel of antibodies to evaluate changes in keratinocyte differentiation, mouse-specific keratin 6 was overexpressed in the suprabasilar, hyperplastic epidermis. Loricrin expression, within the cytoplasm of cells in the stratum granulosum, decreased rapidly postmortem, unlike that in normal mice where it was stable for over 24 hours postmortem. Filaggrin expression, within granules of cells in the stratum granulosum, was prominent, corresponding to hypergranulosis evident by light microscopy in mutant mouse skin. Skin grafts from harlequin ichthyosis mice grafted onto immunodeficient nude mice maintained the phenotype for the 10-week observation period. The mutant gene locus mapped to the proximal end of mouse chromosome 19 and is inherited as a fully penetrant autosomal recessive gene. The harlequin ichthyosis mouse mutation is very similar to human type 2 harlequin ichthyosis for which it may be a good model.

Lectin-deficient ricin toxin intoxicates cells bearing the D-mannose receptor

Ricin toxin with genetic or chemical modification of lectin sites has been previously reported to show markedly reduced cytotoxicity to cells following uptake by several receptors including the mannose receptor. Investigators have hypothesized that an intracellular galactoside-binding function was required for optimal intracellular targeting of ricin for these receptors. We have prepared insect-derived mutant ricin toxin B chain (RTB) with modifications of three lectin side domains (1 alpha, 1 beta, and 2 gamma) yielding a 1000-fold reduced galactoside avidity. After reassociation with plant RTA, the recombinant heterodimer and plant ricin were tested for cytotoxicity on mammalian cells expressing (mouse peritoneal macrophages, J774E cells, and MMR61 cells) or not expressing (KB cells) the D-mannose receptor. Receptor expression was confirmed by immunofluorescence microscopy. Lactose was included in the media to block cell-surface galactoside binding, and mannan was added as a control in each experiment to confirm mannose receptor-specific targeting. Plant ricin A chain (RTA) and E. coli-derived RTA were also tested for cytotoxicity on J774E and KB cells. Both wild-type and lectin-deficient ricin displayed mannose-receptor mediated cell cytotoxicity. This is the first report of a genetically modified ricin showing that RTB intracellular galactose binding activity is not required for ricin cytotoxicity. Sensitivity of mannose-receptor bearing cells, but not control cells, to mannosylated RTA, but not unglycosylated RTA, confirmed these observations. These results imply fusion toxins employing ricin can be prepared with maximal reductions in normal tissue binding.