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A 5.5-yr-old female baboon was evaluated for sexual immaturity. She was small for her age and had normal external female genitalia. However, she lacked cyclical perineal turgescence and displayed atypical coloration of the perineal skin. Laparoscopy revealed a small uterus and absence of both ovaries. Cytogenetic analysis revealed a 42,X,i(X)(q10) karyotype. DNA analysis using loci DXS1683, which maps to Xp22.1, and DXS297, which maps to Xq27.3, was consistent with inheritance of the normal X chromosome from the dam and formation of the isochromosome Xq from the paternal X. [ABSTRACT FROM AUTHOR]

Abstract: The CROZet natural iron bloom and EXport experiment (CROZEX) was carried out around the Crozet Plateau (Southern Ocean) in late austral spring-early summer 2004/2005. The primary aim of this study was to test the hypothesis that natural Fe fertilisation from the islands enhanced primary production to the north of the plateau, leading to elevated carbon export. During the 12-week shipboard study (November–January), size-fractionated chlorophyll-a (chl-a), primary productivity and phytoplankton pigments were determined at 20 stations around the Crozet Plateau, both inside and outside the expected bloom region. Satellite-derived chl-a data from August 2004 to April 2005 revealed that the cruise period covered the declining stage of a large phytoplankton bloom north of the Crozet Plateau. Productivity derived from satellite chl-a data showed a strong north–south gradient, with productivity reaching a maximum of 1.9gCm−2 d−1 in the north (late October), 0.6 over the plateau (late March) and 0.4 in the south (early December). From November to early December, measured chl-a and productivity were still relatively high northwest of the plateau (54–74mgchl-a m−2 and 0.5–1.1gCm−2 d−1), the assemblage being dominated by Phaeocystis sp. and microplankton representing ∼50% of total chl-a. Declining biomass and productivity to the northwest in mid-December was associated with a picoplankton (∼52%) dominated community (19–38mgchl-a m−2 and 0.1–0.4gCm−2 d−1). In contrast, at the north eastern edge of the plateau, a mixed diatom/Phaeocystis dominated bloom (229mgchl-a m−2 and 3gCm−2 d−1) developed in mid-January. South of the plateau in the control high-nutrient low-chlorophyll (HNLC) region, biomass and productivity were always significantly lower, with only a small chl-a peak in December, and a community composed of microflagellates, cyanobacteria and some giant diatoms. Particulate organic carbon (POC):chl-a ratios provided physiological evidence for the impact of Fe fertilisation north of the plateau. The assimilation rate (i.e. integrated productivity normalised to integrated chl-a, ∫P/∫chl-a) did not show significant differences between the north and south, probably due to the late sampling period relative to the bloom peak. Overall, measurements of primary productivity during CROZEX supported the hypothesis of enhanced biomass and production due to natural iron enrichment of the region north of the Crozet Plateau, while south of the plateau, low biomass and productivity resulted primarily from Fe limitation. [Copyright &y& Elsevier]

Background Superior temporal cortices include brain regions dedicated to auditory processing and several lines of evidence suggest structural and functional abnormalities in both schizophrenia and bipolar disorder within this brain region. However, possible glutamatergic dysfunction within this region has not been investigated in adult patients. Methods Thirty patients with schizophrenia (38.67 ± 12.46 years of age), 28 euthymic patients with bipolar I disorder (35.32 ± 9.12 years of age), and 30 age-, gender- and education-matched healthy controls were enrolled. Proton magnetic resonance spectroscopy data were acquired using a 3.0 T Siemens MAGNETOM TIM Trio MR system and single voxel Point REsolved Spectroscopy Sequence (PRESS) in order to quantify brain metabolites within the left and right Heschl's gyrus and planum temporale of superior temporal cortices. Results There were significant abnormalities in glutamate (Glu) (F(2,78) = 8.52, p < 0.0001), N-acetyl aspartate (tNAA) (F(2,81) = 5.73, p = 0.005), creatine (tCr) (F(2,83) = 5.91, p = 0.004) and inositol (Ins) (F(2,82) = 8.49, p < 0.0001) concentrations in the left superior temporal cortex. In general, metabolite levels were lower for bipolar disorder patients when compared to healthy participants. Moreover, patients with bipolar disorder exhibited significantly lower tCr and Ins concentrations when compared to schizophrenia patients. In addition, we have found significant correlations between the superior temporal cortex metabolites and clinical measures. Conclusion As the left auditory cortices are associated with language and speech, left hemisphere specific abnormalities may have clinical significance. Our findings are suggestive of shared glutamatergic abnormalities in schizophrenia and bipolar disorder. [ABSTRACT FROM AUTHOR]

Abstract: The Southern Ocean is largely a High Nutrient Low Chlorophyll (HNLC) region where macronutrient concentrations are high and phytoplankton productivity is low. However, there are productive ‘hot spots’ that sustain large phytoplankton blooms. These areas, maintained by natural iron (Fe) fertilization, are important for the Southern Ocean ecosystem and for driving carbon export. Fe addition on-deck bioassay experiments were conducted on two cruises to the Scotia Sea region of the Southern Ocean (austral spring 2006 and summer 2008) to better understand how Fe controls the microplankton (20–200μm) community structure on a seasonal basis. Light microscopy and fast-repetition rate fluorometry were used to examine changes in the species composition and physiological status of the microplankton community. Bioassays were carried out in three contrasting regions of the Scotia Sea: (1) a naturally Fe-fertilized, high chlorophyll area downstream (north and northwest) of the Islands of South Georgia (DSG); (2) a low Fe, low chlorophyll area upstream (south) of the Islands of South Georgia (USG); and (3) a naturally Fe-fertilized area north of the South Orkney Islands (SOI). Multivariate statistics were applied to the light microscopy results, showing significant differences between the initial microplankton communities for each of the bioassays. These differences were primarily spatial (between regions) and secondarily temporal (between seasons). Significant microplankton community shifts occurred in three of five bioassays, those in spring and summer USG and in summer DSG only. In summer, USG community responses increased significantly in medium (100–1000pgCcell−1) and large (>1000pgCcell−1) diatom species in response to Fe addition. Such a response was consistent with relief from in situ Fe limitation, which favours larger microplankton species with higher Fe requirements and subject to lower grazing pressures. The largest biomass increase in Fe-treated bioassay bottles was in Pseudonitzschia spp., which suggests that this genus may be a particularly important member of the microplankton community in the Scotia Sea. [Copyright &y& Elsevier]