Health advantage for black women: patterns in pre-menstrual dysphoric disorder

BACKGROUND

Pre-menstrual dysphoric disorder (PMDD) is commonly studied in white women; consequently, it is unclear whether the prevalence of PMDD varies by race. Although a substantial proportion of black women report symptoms of PMDD, the Biocultural Model of Women's Health and research on other psychiatric disorders suggest that black women may be less likely than white women to experience PMDD in their lifetimes.

METHOD

Multivariate multinomial logistic regression modeling was used with a sample of 2590 English-speaking, pre-menopausal American women (aged 18-40 years) who participated in the Collaborative Psychiatric Epidemiology Surveys in 2001-2003. The sample consisted of 1672 black women and 918 white women. The measure of PMDD yields a provisional diagnosis of PMDD consistent with DSM-IV criteria.

RESULTS

Black women were significantly less likely than white women to experience PMDD [odds ratio (OR) 0.44, 95% confidence interval (CI) 0.25-0.79] and pre-menstrual symptoms (OR 0.64, 95% CI 0.47-0.88) in their lifetimes, independently of marital status, employment status, educational attainment, smoking status, body mass index, history of oral contraceptive use, current age, income, history of past-month mood disorder, and a measure of social desirability. The prevalence of PMDD was 2.9% among black women and 4.4% among white women.

CONCLUSIONS

This study showed for the first time that black women were less likely than white women to experience PMDD and pre-menstrual symptoms, independently of relevant biological, social-contextual and psychological risk factors. This suggests that PMDD may be an exception to the usual direction of racial disparities in health. Further research is needed to determine the mechanisms that explain this health advantage.

Possible suppression of fetal erythropoiesis by the Kell blood group antibody anti-Kp(a)

Antibodies to antigens in the Kell blood group system are usually immunoglobulin G, and, notoriously, anti-K, anti-k, and anti-Kp(a) can cause severe hemolytic transfusion reactions, as well as severe hemolytic disease of the fetus and newborn (HDFN). It has been shown that the titer of anti-K does not correlate with the severity of HDFN because, in addition to immune destruction of red blood cells (RBCs), anti-K causes suppression of erythropoiesis in the fetus, which can result in severe anemia. We report a case involving anti-Kp(a) in which one twin was anemic and the other was not. Standard hemagglutination and polymerase chain reaction (PCR)-based tests were used. At delivery, anti-Kp(a) was identified in serum from the mother and twin A, and in the eluate prepared from the baby’s RBCs. PCR-based assays showed twin A (boy) was KEL*841T/C (KEL*03/KEL*04), which is predicted to encode Kp(a+b+). Twin B (girl) was KEL*841C/C (KEL*04/KEL*04), which is predicted to encode Kp(a–b+). We describe the first reported case of probable suppression of erythropoiesis attributable to anti-Kp(a). One twin born to a woman whose serum contained anti-Kp(a) experienced HDFN while the other did not. Based on DNA analysis, the predicted blood type of the affected twin was Kp(a+b+) and that of the unaffected twin was Kp(a–b+). The laboratory findings and clinical course of the affected twin were consistent with suppression of erythropoiesis in addition to immune RBC destruction.

Role of forensic odontology in the world's major mass disasters: facts and figures

Forensic identification of the victims in mass disasters is essential, not only for humanitarian reasons, but also for civil or criminal investigative need. The number of victims identified with the help of forensic odontology in various mass disasters in the world has been analysed and discussed. The result depicts the necessity of keeping proper dental records at institutional and individual level. Thus the use of forensic odontology in a series of mass disasters has been explored. The most common aspect of forensic odontology that a general practitioner is likely to encounter is the supply of ante-mortem records to aid in human identification.

CLINICAL RELEVANCE

The need for proper dental record-keeping by general dental practitioners is highlighted by discussing the role of forensic odontology in some of the world's major mass disasters.

Three-photon microscopy shows that somatic release can be a quantitatively significant component of serotonergic neurotransmission in the mammalian brain

Recent experiments on monoaminergic neurons have shown that neurotransmission can originate from somatic release. However, little is known about the quantity of monoamine available to be released through this extrasynaptic pathway or about the intracellular dynamics that mediate such release. Using three-photon microscopy, we directly imaged serotonin autofluorescence and investigated the total serotonin content, release competence, and release kinetics of somatic serotonergic vesicles in the dorsal raphe neurons of the rat. We found that the somata of primary cultured neurons contain a large number of serotonin-filled vesicles arranged in a perinuclear fashion. A similar distribution is also observed in fresh tissue slice preparations obtained from the rat dorsal raphe. We estimate that the soma of a cultured neuron on an average contains about 9 fmoles of serotonin in about 450 vesicles (or vesicle clusters) of < or =370 nm average diameter. A substantial fraction (>30%) of this serotonin is released with a time scale of several minutes by K(+)-induced depolarization or by para-chloroamphetamine treatment. The amount of releasable serotonin stored in the somatic vesicles is comparable to the total serotonin content of all the synaptic vesicles in a raphe neuron, indicating that somatic release can potentially play a major role in serotonergic neurotransmission in the mammalian brain.

Recurrent ameloblastoma of the infratemporal fossa: diagnostic implications and a review of the literature

It is unusual for odontogenic tumours such as ameloblastoma to occur in the infratemporal fossa. Although these odontogenic tumours usually arise in jaws, they can infiltrate into the infratemporal region, pterygomaxillary space or fissure, invading soft tissues by way of extension. A case of recurrent ameloblastoma in the infratemporal fossa region arising from an extension of the lesion from the site of previous occurrence in the right mandibular body is reported.

Zinc Lowers Amyloid-β Toxicity by Selectively Precipitating Aggregation Intermediates

Soluble amyloid-beta (Abeta) aggregates are suspected to play a major role in Alzheimer's disease. Zn2+ at a concentration of a few micromolar, which is too dilute to affect the precipitation equilibrium of Abeta, can destabilize these aggregates [Garai, K., Sengupta, P., Sahoo, B., and Maiti, S. (2006) Biochem. Biophys. Res. Commun. 345, 210-215]. Here we investigate the nature of these aggregates in the context of the precipitation pathway, the mechanism underlying their destabilization, and the biological consequences of this destabilization. We show that the larger soluble aggregates (size >10 nm) form only in supersaturated Abeta solutions, implying that they are intermediates in the pathway toward fibril formation. We also show that Zn2+ destabilizes these intermediates by accelerating their aggregation kinetics. The resulting change in the size distribution of the Abeta solution is sufficient to eliminate its toxicity to cultured mammalian neurons. Our results provide an explanation for the existing observations that Zn2+ at a concentration of a few micromolar significantly reduces Abeta toxicity.

Quantitative measurement of serotonin synthesis and sequestration in individual live neuronal cells

Synthesis and subsequent sequestration into vesicles are essential steps that precede neurotransmitter exocytosis, but neither the total neurotransmitter content nor the fraction sequestered into vesicles have been measured in individual live neurons. We use multiphoton microscopy to directly observe intracellular and intravesicular serotonin in the serotonergic neuronal cell line RN46A. We focus on how the relationship between synthesis and sequestration changes as synthesis is up-regulated by differentiation or down-regulated by chemical inhibition. Temperature-induced differentiation causes an increase of about 60% in the total serotonin content of individual cells, which goes up to about 10 fmol. However, the number of vesicles per cell increases by a factor of four and the proportion of serotonin sequestered inside the vesicles increases by a factor of five. When serotonin synthesis is inhibited in differentiated cells and the serotonin content goes down to the level present in undifferentiated cells, the sequestered proportion still remains at this high level. The total neurotransmitter content of a cell is, thus, an unreliable indicator of the sequestered amount.

Some neurophysiological constraints on models of word naming

The pronunciation of irregular words in deep orthographies like English cannot be specified by simple rules. On the other hand, the fact that novel letter strings can be pronounced seems to imply the existence of such rules. These facts motivate dual-route models of word naming, which postulate separate lexical (whole-word) and non-lexical (rule-based) mechanisms for accessing phonology. We used fMRI during oral naming of irregular words, regular words, and nonwords, to test this theory against a competing single-mechanism account known as the triangle model, which proposes that all words are handled by a single system containing distributed orthographic, phonological, and semantic codes rather than word codes. Two versions of the dual-route model were distinguished: an 'exclusive' version in which activation of one processing route predominates over the other, and a 'parallel' version in which both routes are equally activated by all words. The fMRI results provide no support for the exclusive dual-route model. Several frontal, insular, anterior cingulate, and parietal regions showed responses that increased with naming difficulty (nonword > irregular word > regular word) and were correlated with response time, but there was no activation consistent with the predicted response of a non-lexical, rule-based mechanism (i.e., nonword > regular word > irregular word). Several regions, including the angular gyrus and dorsal prefrontal cortex bilaterally, left ventromedial temporal lobe, and posterior cingulate gyrus, were activated more by words than nonwords, but these 'lexical route' regions were equally active for irregular and regular words. The results are compatible with both the parallel dual-route model and the triangle model. 'Lexical route' regions also showed effects of word imageability. Together with previous imaging studies using semantic task contrasts, the imageability effects are consistent with semantic processing in these brain regions, suggesting that word naming is partly semantically-mediated.

Spontaneous coronary artery dissection in the postpartum period: association with antiphospholipid antibody

Spontaneous coronary artery dissection (SCAD) is an extremely uncommon cause of myocardial infarction, occurring predominantly in women during or after pregnancy. The exact aetiology is unknown. This report describes a 33 year postpartum woman with diagnosed SCAD who tested positive for anticardiolipin antibody. This is the first case of SCAD in a patient with antiphospholipid antibody. The authors hypothesised that there should be a strong association between them.