Demographic monitoring is required in threatened species management, yet effective and efficient monitoring is challenging for species that are difficult to capture or susceptible to capture stress. One possible monitoring approach for such species is non-invasive genetic sampling with capture–recapture methods (genetic capture–recapture). We evaluated the performance of genetic capture–recapture in a challenging model system, monitoring the threatened Sonoran pronghorn Antilocapra americana sonoriensis. In an effort to determine the best (i.e. efficient, accurate, precise, cost-effective) method for abundance estimation, we used simulations to examine the optimal genetic capture–recapture faecal sampling design for this population. We simulated encounter histories for 100–300 individuals, with 0.33–3.33 samples/individual/session, in 1–3 sampling sessions. We explored trade-offs between sample size, number of sessions and multi-session (MARK) versus single-session (capwire) closed capture–recapture abundance estimators, and an accurate and precise estimate. We also compared the cost between the genetic capture–recapture approaches and current aerial monitoring methods. Abundance was biased positively in capwire and negatively in MARK. Bias increased and precision decreased with fewer samples/individual/session. Annual genetic capture–recapture monitoring cost was nearly twice the cost of aerial surveys, although genetic capture–recapture methods provided much higher precision. However at the current estimated abundance (c. 200), the same level of precision achieved with aerial methods can be obtained by collecting 0.75 samples/individual in a single session, for an annual cost saving of > USD 4,000. This approach of comparing estimator performance and cost can easily be applied to other systems and is a useful evaluation for managers to implement prior to designing capture–recapture studies.

The aim of this study was to evaluate the influence of two-dimensional (2D) and three-dimensional (3D) alginate culture systems on in vitro development of pre-antral caprine follicles. In addition, the influence of the reproductive age of the ovary donor on the in vitro culture success was investigated. Pre-antral follicles from pre-pubertal or adult goats were isolated and cultured directly on a plastic surface (2D) or encapsulated in an alginate-based matrix (3D). After 18 days, the oocytes underwent in vitro maturation (IVM) and in vitro fertilization (IVF) to produce embryos. The 3D system showed higher rates of follicle survival, lower rates of oocyte extrusion, and a greater number of recovered oocytes for IVM and IVF (P < 0.05). Only pre-antral follicles from adult animals produced MII oocytes and embryos. The estradiol concentrations increased from day 2 to day 12 of culture in all groups tested (P < 0.05). Conversely, progesterone concentrations were lower in 3D-cultured follicles than in 2D-cultured follicles, with differences on days 2 and 6 of culture (P < 0.05). We provide compelling evidence that a 2D or 3D alginate in vitro culture system offers a promising approach to achieving full in vitro development of caprine pre-antral follicles to produce mature oocytes that are capable of fertilization and viable embryos.

The hypothesis tested was that, in schizophrenia, corpus callosum size would be reduced, particularly in the region responsible for communication between both temporal lobes. This is supported by knowledge of: (a) anatomical homotopicity and functional specialization of fibres within the corpus callosum; (b) evidence linking structural and functional deficits of the corpus callosum and left temporal lobe with schizophrenia; and (c) that temporal lobe neuronal fibres pass through the middle region of the corpus callosum. Brain area and corpus callosum areas, widths and length were measured on mid-sagittal MRI scans using a computer outlining method. Scans from 30 schizophrenics and 44 normal subjects were compared. Mid-sagittal brain area, corpus callosum area, length and anterior widths were reduced in the schizophrenic group compared with controls. A significant area difference between schizophrenics and controls was seen in the mid-corpus callosum which communicates between the temporal lobes, including the superior temporal gyri. In schizophrenics, corpus callosum area reduction was not accounted for by brain area shrinkage alone. Differences between the two groups were accounted for by comparisons between males only. These findings support the hypothesis and the possibility that localized abnormalities of bilaterally connected brain regions might have secondary effects on their homotopically distributed fibres within the corpus callosum.

Background. A better understanding of the neural basis of social cognition including mindreading (or theory of mind) and empathy might help to explain some deficits in social functioning in people with schizophrenia. Our aim was to review neuroimaging and neuropsychological studies on social cognition, as they may shed light on the neural mechanisms of social cognition and its dysfunction in patients with schizophrenia.

Method. A selective literature review was undertaken.

Results. Neuroimaging and neuropsychological studies suggest convergence upon specific networks for mindreading and empathy (the temporal cortex, amygdala and the prefrontal cortex). The frontal lobe is likely to play a central role in enabling social cognition, but mindreading and empathic abilities may require relatively different weighting of subcomponents within the same frontal-temporal social cognition network.

Conclusions. Disturbances in social cognition may represent an abnormal interaction between frontal lobe and its functionally connected cortical and subcortical areas. Future studies should seek to explore the heterogeneity of social dysfunction within schizophrenia.

Background. Lack of insight is frequently observed in schizophrenia. Relationships have been noted between poor insight, clinical symptoms and cognitive impairments but the findings are inconsistent. There have been some recent attempts to relate poor insight to neuro-anatomical measures.

Method. We assessed insight, positive and negative symptoms of schizophrenia, cognitive performance, and whole brain volumes in a sample of 78 DSM-IV male schizophrenics and 36 normal male comparison subjects matched for age and IQ. Subjects underwent a dual-echo MRI brain scan to establish grey, white and whole brain volumes.

Results. Poor Wisconsin Card Sorting Test performance inversely correlated with insight in schizophrenic patients, as did the symptoms alogia, anhedonia, avolition/apathy, affective flattening, inappropriate affect, thought disorder and delusions. The presence of inappropriate affect, delusions and thought disorder, showed the most significant impact on insight levels. There were no significant correlations between whole brain, white and grey matter volume and degree of insight.

Conclusions. The results suggest that poor insight is significantly related to schizophrenic psychopathology, and confirm that there is a relationship between insight and executive performance. Awareness of illness is not related to any global brain measures, suggesting future investigations should pay attention to more specific cortical regions such as the frontal cortex.

Rates of acute hepatitis B are high in Moldova, but the prevalence of chronic infection is unknown. In 1994, we surveyed children and pregnant women, collected demographic information, and drew blood for laboratory testing. Among the 439 children (mean age, 5 years), the prevalence of antibody to hepatitis B core antigen (anti-HBc) and hepatitis B surface antigen (HBsAg) were 17·1 and 6·8%, respectively. Among the 1098 pregnant women (mean age, 26 years), 52·4% were anti-HBc-positive and 9·7% were HBsAg-positive. Of the HBsAg-positive pregnant women, 35·6% were hepatitis B e antigen (HBeAg) positive and 18·3% had antibodies to hepatitis D virus. The prevalence of antibody to hepatitis C virus was 1·4% in children and 2·3% in pregnant women. The high HBeAg prevalence among HBsAg-positive pregnant women and the high anti-HBc prevalence among children indicate that both perinatal and early childhood transmission contribute to the high hepatitis B virus endemicity in Moldova.

Background. Many studies have separately reported abnormalities of frontal and temporal lobe structures in schizophrenia, but little is known of structural fronto-temporal associations in this condition. We investigated whether male patients with chronic schizophrenia would show abnormal patterns of correlation between regional brain volumes.

Methods. Structural magnetic resonance images of the brain in 42 patients were compared with 43 matched unaffected controls. We explored the pattern of association between regional brain volumes by correlational analyses, and non-parametrically tested for significance of between-group differences by randomization.

Results. The schizophrenics demonstrated significant volume deficits in several brain regions (left temporal lobe and hippocampus, right dorsolateral prefrontal cortex), and significant volume increases in the ventricular system (third ventricle and left temporal horn of the lateral ventricle). Controls demonstrated large positive correlations (r>0·4) between prefrontal and temporal lobe regions. By contrast, inter-regional correlations significantly reduced in schizophrenics included those between prefrontal, anterior cingulate and temporal regions, and between posterior cingulate and hippocampus (P<0·05). The most salient abnormality in patients was a dissociation between prefrontal and superior temporal gyrus volumes (P<0·01).

Conclusions. These results support the existence of a relative ‘fronto-temporal dissociation’ in schizophrenia which we suggest may be due to lack of mutually trophic influences during frontal and temporal lobe development.