bluuebunny/crossref_metadata_2025 huggingface dataset:
Pleomorphic hyalinizing angiectatic tumor with a sarcomatous component recurring as high‐grade myxofibrosarcoma
Authors: Kazakov Dmitry V. , Pavlovsky Michal , Mukensnabl Petr , Michal Michal
Published: April 2007

Pleomorphic hyalinizing angiectatic tumor (PHAT) of the soft tissue is a rare distinctive tumor listed as a benign neoplasm in the new World Health Organization classification. It may recur and most reported recurrent tumors retained the typical morphological appearance of PHAT; rare tumors recurred with the appearance of a sarcoma. Reported herein is an additional example of recurrent PHAT, but in contrast to the previously described cases the present tumor morphologically qualified as a sarcoma from the very beginning; it recurred as a high‐grade myxofibrosarcoma. A 76‐year‐old woman presented with a solitary subcutaneous tumor in the axilla that was surgically removed. Seven months later, the patient experienced a local recurrence. Microscopically, the typical features of PHAT were identified in the initial lesion, namely hyalinized, fibrin‐containing vessels and pleomorphic stromal cells; there were areas of hemorrhage and necrosis. Additionally, peripherally located areas of the tumor manifested highly pleomorphic cells with frequent atypical mitoses, producing a sarcomatous appearance. The mitotic index in the sarcomatous part was 1/10 high‐power fields (HPF). Hyalinized, fibrin‐containing vessels were absent in these sarcomatous areas, and the stroma was myxoid. The recurrent lesion was composed of large highly pleomorphic oval, round, spindled or bizarre cells with a high mitotic rate, ranging from 3/10 HPF to 7/10 HPF. The neoplastic cells were arranged haphazardly in a myxoid matrix. Hyalinized, fibrin‐containing vessels typical for PHAT were absent. PHAT may be more aggressive than previously thought, and PHAT may encompass a morphological spectrum of the lesion ranging from benign to malignant.
Midkine expression in colorectal tumors: Correlation with Ki‐67 labeling in sporadic, but not ulcerative colitis‐associated ones
Authors: Tokuyama Wataru , Mikami Tetuo , Fujiwara Mutsunori , Matsui Takashi , Okayasu Isao
Published: April 2007

Midkine (MK) is a heparin‐binding growth factor encoded by a retinoic acid responsive gene. To investigate the possible contribution of MK to genesis of colorectal carcinomas, an immunohistochemical examination of protein expression was conducted in sporadic and ulcerative colitis (UC)‐associated tumors. MK expression significantly differed among normal mucosa, adenomas with low‐grade dysplasia (LGD), adenomas with high‐grade dysplasia (HGD) and invasive adenocarcinomas: MK expression was increased along with tumor progression. UC‐associated lesions (regenerative mucosa of UC, UC‐associated dysplasia and UC‐associated adenocarcinoma) had similar variations. MK expression in UC‐associated lesions was significantly higher than in normal mucosa, although there was no significant difference among UC‐associated lesions. However, in UC‐associated dysplasia, MK expression did not differ between the upper and lower halves, in contrast to adenoma with LGD and HGD, in which MK expression was significantly higher in the upper than lower halves, corresponding to cell proliferative zone. Furthermore, correlations with Ki‐67 and single‐strand DNA labeling, respectively, reflecting cellular proliferative activity and apoptosis, were noted in sporadic but not UC‐associated lesions. These results suggest that MK is involved in genesis/development of sporadic colorectal tumors as well as of UC‐associated tumors, but might contribute differently to genesis/development in these two types of tumors.
Role of matrix metalloproteinases and their tissue inhibitor of metalloproteinases in myxomatous change of cardiac floppy valves
Authors: Togashi Mayuko , Tamura Koichi , Nitta Takashi , Ishizaki Masamichi , Sugisaki Yuichi , Fukuda Yuh
Published: April 2007

To clarify the underlying cause of myxomatous changes in cardiac floppy valves, the expression of the matrix metalloproteinases (MMP) and the tissue inhibitors of metalloproteinases (TIMP) was investigated in cardiac valves. Valves were obtained from nine patients with floppy valves, from 13 patients with other valvular disease types, and from four patients with normal valves. Immunohistochemical analyses for MMP‐2, MMP‐9, TIMP‐1, and TIMP‐2, and gelatin zymography for MMP‐2 and MMP‐9 were performed. Compared with the spongiosa of normal valves, the myxomatous area of floppy valves had stronger immunohistochemical reaction to MMP‐2 and MMP‐9, and weaker reaction to TIMP‐2. Activated MMP‐2 and MMP‐9 were detected in eight out of nine cases of floppy valves. Activated MMP‐2 was detected at low levels in two cases of normal valves showing mild expansion of the spongiosa without macroscopic floppiness. The ratio of active/total MMP‐2 and MMP‐9 increased in floppy valves compared with normal valves. These results suggest that the imbalance between MMP and TIMP and the increased activity of MMP‐2 and MMP‐9 may correlate with myxomatous changes observed in floppy valves. Valves with a slight myxomatous change and activated MMP‐2 may develop into floppy valves with increases in the activity of MMP.
Historical use of substrate‐borne acoustic production within the Hemiptera: first record for an Australian Lophopid (Hemiptera, Lophopidae)
Authors: Soulier‐Perkins Adeline , Sueur Jérôme , Hoch Hannelore
Published: April 2007

Abstract  Here the first record of communication through substrate‐borne vibrations for the Lophopidae family is reported. The signals from Magia subocellata that the authors recorded were short calls with a decreasing frequency modulation. Acoustic vibrations have been observed for other families within the Hemiptera and a scenario concerning the historical use of vibrational communication within the Hemiptera is tested using a phylogenetic inference. The most parsimonious hypothesis suggests that substrate‐borne communication is ancestral for the hemipteran order and highlights the groups for which future acoustic research should be undertaken.
Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) chemical control: insecticide efficacy associated with the three consecutive spray strategy
Authors: Broughton Sonya , Herron Grant A
Published: April 2007

Abstract  After the initial 1993 discovery of Frankliniella occidentalis, western flower thrips, in Australia, temporary chemical control permits were issued to facilitate their insecticidal control. However, these permits were based on established endemic pests of Australian horticulture rather than demonstrated efficacy against F. occidentalis, and laboratory bioassays of Australian field‐collected F. occidentalis suggested that some permit application rates were too low to be effective. In 2002 and 2003 field‐based trials were carried out in strawberry and lettuce to collect field‐generated efficacy data to verify the laboratory conclusions. It was found that by increasing field application rates above the existing permit rate, efficacy was increased, but not for all insecticides and not for all thrips life stages. Increasing the rate of abamectin and endosulfan in strawberry increased control of adults and larvae and increasing the rate of endosulfan in lettuce increased efficacy against larvae only. Spinosad was effective at both rates tested in strawberry, suggesting that the current permit rate could be reduced. The ability to use reduced rates may be useful if used in combination with Integrated Pest Management programs.
Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) chemical control: residues associated with the three consecutive spray strategy
Authors: Herron Grant , Broughton Sonya , Clift Alan
Published: April 2007

Abstract  Chemical control of western flower thrips Frankliniella occidentalis requires three consecutive applications of the same pesticide, 3–6 days apart. Initially, pesticides recommended for western flower thrips control were based on established maximum residue limits (MRLs) from previously established use on pests other than F. occidentalis, rather than product efficacy against F. occidentalis. Moreover, MRLs were based on a single application rather than three consecutive sprays. Chemical residues associated with the three‐spray strategy were not quantified. Here those residues are quantified and the scope for rate increases is further tested, as laboratory bioassays suggest that some current permit rates may be too low to be effective. At established withholding periods (WHPs), current permit rate applications of abamectin (0.018 g/L) on strawberry and tomato, and methidathion (0.5 g/L) and endosulfan (0.666 g/L) on lettuce produced residues above the current Australian MRL. Results indicated that a higher than the current permit rate for endosulfan (2.0 g/L) could be sustained on cucumber and strawberry at established WHPs, but would require an extension to the current WHP. Similarly, a modest increase in methidathion (1.0 g/L) rate on tomato could be practical, again with a WHP extension. In each instance additional supporting data are required to accurately quantify the proposed WHP extensions.
Short‐range dispersal of recently emerged males and females of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) monitored by sticky sphere traps baited with protein and Lynfield traps baited with cue‐lure
Authors: Weldon Christopher , Meats Alan
Published: April 2007

Abstract  Dispersal of immature male and female Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), was assessed over a period of 1 week from a single release point on three separate occasions using an array of Lynfield traps baited with cue‐lure and odouriferous yellow or black sticky spheres baited with food lure (protein autolysate). Lynfield traps recaptured males; yellow or black spheres recaptured both sexes in approximately equal proportions, although at a much lower rate. As a percentage of the recapture rate for males by Lynfield traps, the mean recapture rate for yellow spheres ranged from 1.0% to 7.5% for males and 0.7% to 4.0% for females, whereas the recapture rates for black spheres ranged from 0.4% to 3.6% and 0.6% to 1.8%, respectively. The rate of recapture of sterile male flies was greater than that of unsterilised flies; this may have been due to a faster maturation rate in sterile males or because a greater proportion of them remained within the trap array rather than dispersing. There was no significant trend in recapture rate with distance from the release point to the edge of the array (88 m), except in the case of females on sticky traps where no trend was detected between 19 and 88 m. These results lend support to assumptions made about the distribution of males and females with respect to the minimum breeding density of fruit fly propagules invading a fly‐free zone, and the method chosen to distribute sterile B. tryoni for the sterile insect technique.
Parasitoid complex of diamondback moth in south‐east Queensland: first records of Oomyzus sokolowskii (Hymenoptera: Eulophidae) in Australia
Authors: Furlong Michael J , Zalucki Myron P
Published: April 2007

Abstract  Surveys for parasitoids attacking larvae and pupae of Plutella xylostella L. (Lepidoptera: Plutellidae) were conducted in the Brassica agro‐ecosystem of the Lockyer valley, south‐east Queensland between 1999 and 2002. Parasitised hosts were collected from infested plants placed in Brassica crops during the growing season (February–October) and from the natural P. xylostella population on the common weed Rapistrum rugosum L. (Brassicaceae) during the summer production break (November–January). Five species of primary parasitoids were recorded and they ranked in order of abundance: Diadegma semiclausum Hellén (Hymenoptera: Ichneumonidae) > Diadromus collaris Gravenhorst (Hymenoptera: Ichneumonidae) = Apanteles ippeus Nixon (Hymenoptera: Braconidae) > Brachymeria phya Walker (Hymenoptera: Chalcididae) = Oomyzus sokolowskii Kurdjumov (Hymenoptera: Eulophidae). In crops, parasitoids were reared from 23 of the 30 P. xylostella cohorts studied; D. semiclausum was collected at 21 sites, O. sokolowskii at eight sites, D. collaris at six sites, A. ippeus at three sites and B. phya at a single site. The incidence and abundance of hosts parasitised by D. semiclausum increased markedly in winter and early spring months and parasitism rates as high as 95% were recorded. Diadromus collaris and O. sokolowskii were recovered at low levels throughout 2000 and 2001 but parasitism rates never exceeded 11% or 8%, respectively. Parasitism rates are compared with other mortality factors and the contribution that each species of parasitoid makes to the biological control of the pest in the region is considered. Oomyzus sokolowskii has also been reared from P. xylostella collected in Tasmania and Western Australia. This study is the first report of the incidence O. sokolowskii in Australia; however, its wide distribution indicates that its establishment is not a recent event.
Distribution of sibling species of the Anopheles annulipes complex (Diptera: Culicidae) in the Townsville region of Australia
Authors: Boyd Ann‐Marie , Foley Desmond H
Published: April 2007

Abstract  As members of the Anopheles annulipes species complex have been implicated as possible malaria vectors in the past, their response to dams and urban development is of medical interest. We collected An. annulipes sensu lato (s.l.) Walker from the Ross River Dam and environs of tropical north Queensland, and scored them for 28 allozyme loci. Allozyme genotype data were analysed by the Unweighted Pair Group Method of Analysis applied to percentage fixed allelic differences (%FD) and by a Bayesian clustering approach. Both approaches revealed four groups, which differed by more than 25%FD, suggesting four species. Specimens sequenced for the Internal transcribed spacer subunit 2 of rDNA suggested that three of these groups were An. annulipes species D, species I and species O. Anopheles annulipes species D occurred in the Ross River and the Ross River Dam, An. annulipes species O inhabited rock pools, and An. annulipes species I inhabited both rock pools and artificial containers in domestic situations. Construction of the Ross River Dam appears to have benefited at least An. annulipes species D, and nearby housing development An. annulipes species I. Although An. annulipes s.l. does not appear to be a major medical risk, mosquito monitoring around Townsville may need to take into account the multispecies status of this taxon.
Results of primary percutaneous coronary intervention in a consecutive group of patients with acute ST elevation myocardial infarction at a tertiary Australian centre
Authors: Van Gaal W. J. , Clark D. , Barlis P. , Lim C. C. S. , Johns J. , Horrigan M.
Published: April 2007

Background: Multicentre randomized controlled trials (RCT) of primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI) have consistently shown lower mortality compared with fibrinolysis, if carried out in a timely manner. Although primary PCI is now standard of care in many centres, it remains unknown whether results from RCT of selected patients are generalizable to a ‘real‐world’ Australian setting. The primary goal of this study was to evaluate whether a strategy of routine invasive management for patients with STEMI can achieve 30‐day and 12‐month mortality rates comparable with multicentre RCT. Secondary goals were to determine 30‐day mortality rates in prespecified high‐risk subgroups, and symptom‐onset‐ and door‐to‐balloon‐inflation times.

Methods: A retrospective observational study of 189 consecutive patients treated with primary PCI for STEMI in a single Australian centre performing PCI for acute STEMI.

Results: All‐cause mortality was 6.9% at 30 days, and 10.4% at 12 months. Mortality in patients presenting without cardiogenic shock was low (2.4% at 30 days; 5.0% at 12 months), whereas 12‐month mortality in patients with shock was higher, particularly in the elderly (29.4% for patients <75 years; 85.7% for patients ≥75 years, P = 0.01). Symptom‐onset‐to‐balloon‐inflation time was ≤4 h in 56% of patients (median 231 min); however, a door‐to‐balloon time of <90 min was achieved in only 20% (median 133 min).

Conclusion: Mortality and symptom‐onset‐to‐balloon‐inflation times reported in RCT of primary PCI for STEMI are generalizable to ‘real‐world’ Australian practice; however, further efforts to reduce door‐to‐balloon times are required.
Viral hepatitis among male amphetamine‐inhaling abusers
Authors: Lai S.‐W. , Chang W.‐L. , Peng C.‐Y. , Liao K.‐F.
Published: April 2007

Background: Few studies have focused on the clandestinely consumed amphetamine as a primary drug. The purpose of this study was to estimate the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and the related factors in male amphetamine‐inhaling abusers.

Methods: This was a cross‐sectional study. From November 2004 to February 2005, 285 amphetamine‐inhaling male subjects at one prison in Taiwan and 285 age‐matched healthy men without history of using illicit drugs or tattooing were enrolled. A face‐to‐face interview focusing on amphetamine‐addicted history and sociodemographic information was used. Hepatitis B surface antigen (HBsAg) and anti‐HCV were tested.

Results: The mean age of the subjects was 34.1 ± 8.6 years (range 17–75 years). Among 285 subjects, 13.3% were positive for HBsAg, 20.0% positive for anti‐HCV and 2.5% positive for combined HBsAg and anti‐HCV. Multivariate logistic regression analysis showed that tattoo (odds ratio (OR) 2.97, 95% confidence interval (CI) 1.37–6.43) and elevated alanine aminotransferase (ALT) (OR 3.15, 95% CI 1.49–6.66) were independently related to persons being anti‐HCV positive. Elevated ALT was related to persons being HBsAg positive (OR 2.60, 95% CI 1.15–5.89).

Conclusion: Screening of HBV and HCV infection among amphetamine‐inhaling abusers remains necessary. Tattoo and elevated ALT are identified as the related factors for being anti‐HCV positive. Elevated ALT is the related factor for being HBsAg positive.
Lateral hypothalamic ‘command neurons’ with axonal projections to regions involved in both feeding and thermogenesis
Authors: Oldfield B. J. , Allen A. M. , Davern P. , Giles M. E. , Owens N. C.
Published: April 2007

The concept of ‘command neurons’, whereby single neurons mediate complex and complementary motor functions to generate a stereotyped behaviour, is well developed in invertebrate physiology. The term has also been adopted more recently to explain the neural basis of ‘fight or flight’. In this study we have investigated the possibility that single lateral hypothalamic neurons have the necessary neuroanatomical connections to coordinate two complementary limbs of body weight control, feeding and thermogenesis, thereby acting as ‘command neurons’. The transynaptic retrograde transport of pseudorabies virus (Bartha) from a thermogenic endpoint in the brown adipose tissue of rats has been used in conjunction with other neuronal tracers, introduced into putative CNS feeding centres, to assess the potential for the involvement of command neurons in coordinating these processes. In discrete regions of the lateral hypothalamus, neurons have been identified which have the necessary complement of orexigenic peptides and collateral branching axons to both putative feeding sites and thermogenic sites in brown fat to qualify as candidate central command neurons controlling body weight.
cAMP mediates ammonia‐induced programmed cell death in the microglial cell line BV‐2
Authors: Svoboda Nina , Zierler Susanna , Kerschbaum Hubert H.
Published: April 2007

Although ammonia is a well‐known neuropathogenic factor, the cellular mechanisms of ammonia toxicity are less characterized. Up to now, the main focus of ammonia toxicity has been on astrocytes and neurons. Despite the significance of microglia in neurodegenerative diseases, little is known about their responsiveness to ammonia. In the present study, we found that ammonia triggered mitosis at concentrations between 30 μm and 3.0 mm but apoptosis at concentrations ≥ 1.0 mm in the murine microglial cell line BV‐2. Most apoptotic cells showed an accumulation of condensed chromatin at the nuclear envelope, blebbing of the plasma membrane, formation of apoptotic bodies and an increase in caspase 3/7 activity. Blockade of caspase 3/7 activity by Ac‐DEVD‐CHO suppressed ammonia‐induced apoptosis. Surprisingly, some BV‐2 cells exposed to ammonia displayed clear signs of mitotic catastrophe, a type of cell death occurring during mitosis. In a further series of experiments, we found that cyclic adenosine 3′,5′‐monophosphate (cAMP) mediated the apoptogenic effects of ammonia, because (i) ammonia dose‐dependently elevated the intracellular cAMP level, (ii) blockade of the adenylyl cyclase by SQ‐22536 suppressed ammonia‐induced apoptosis, (iii) inhibition of phosphodiesterases (PDEs) by the nonselective PDE inhibitor IBMX, or by the PDE4‐selective inhibitor rolipram, increased the relative number of apoptotic cells, and (iv) the cAMP analogues 8‐bromoadenosine cAMP and Sp‐cAMP mimicked the effect of ammonia and triggered apoptosis. Taken together, our results indicate that distinct concentrations of ammonia trigger opposite signalling pathways in microglial cells.
Paradoxical opsin expressing cells in the inner retina that are augmented following retinal degeneration
Authors: Semo Ma'ayan , Vugler Anthony A. , Jeffery Glen
Published: April 2007

Here we reveal a population of cells that express cone photoreceptor opsins that are located in the inner retina, distant from outer retinal photoreceptors. These cells are present in rodents and human. They also express a range of key proteins critical in the cone phototransduction cascade and make contact with other retinal neurons. Their opsins are not generally confined to cellular specialized regions but are present throughout the plasma membrane, although their nuclear configurations are similar to those of outer retinal cones. This population is distinct from the ganglion cells that contain melanopsin and which are known to be inner retinal irradiance detectors regulating circadian behaviour. Surprisingly, the size of the population of short wavelength opsin positive cells in the ganglion cell layer is plastic. In normal animals their number declines with age. However, their numbers increase significantly in response to outer retinal photoreceptor loss, probably by drawing on a pool of inner retinal cells that express cone specific markers, but not opsins.
Neurotoxic lesions of ventrolateral prefrontal cortex impair object‐in‐place scene memory
Authors: Wilson Charles R. E. , Gaffan David , Mitchell Anna S. , Baxter Mark G.
Published: April 2007

Disconnection of the frontal lobe from the inferotemporal cortex produces deficits in a number of cognitive tasks that require the application of memory‐dependent rules to visual stimuli. The specific regions of frontal cortex that interact with the temporal lobe in performance of these tasks remain undefined. One capacity that is impaired by frontal–temporal disconnection is rapid learning of new object‐in‐place scene problems, in which visual discriminations between two small typographic characters are learned in the context of different visually complex scenes. In the present study, we examined whether neurotoxic lesions of ventrolateral prefrontal cortex in one hemisphere, combined with ablation of inferior temporal cortex in the contralateral hemisphere, would impair learning of new object‐in‐place scene problems. Male macaque monkeys learned 10 or 20 new object‐in‐place problems in each daily test session. Unilateral neurotoxic lesions of ventrolateral prefrontal cortex produced by multiple injections of a mixture of ibotenate andN‐methyl‐d‐aspartate did not affect performance. However, when disconnection from inferotemporal cortex was completed by ablating this region contralateral to the neurotoxic prefrontal lesion, new learning was substantially impaired. Sham disconnection (injecting saline instead of neurotoxin contralateral to the inferotemporal lesion) did not affect performance. These findings support two conclusions: first, that the ventrolateral prefrontal cortex is a critical area within the frontal lobe for scene memory; and second, the effects of ablations of prefrontal cortex can be confidently attributed to the loss of cell bodies within the prefrontal cortex rather than to interruption of fibres of passage through the lesioned area.
Transplantation of conditionally immortal auditory neuroblasts to the auditory nerve
Authors: Sekiya Tetsuji , Holley Matthew C. , Kojima Ken , Matsumoto Masahiro , Helyer Richard , Ito Juichi
Published: April 2007

Cell transplantation is a realistic potential therapy for replacement of auditory sensory neurons and could benefit patients with cochlear implants or acoustic neuropathies. The procedure involves many experimental variables, including the nature and conditioning of donor cells, surgical technique and degree of degeneration in the host tissue. It is essential to control these variables in order to develop cell transplantation techniques effectively. We have characterized a conditionally immortal, mouse cell line suitable for transplantation to the auditory nerve. Structural and physiological markers defined the cells as early auditory neuroblasts that lacked neuronal, voltage‐gated sodium or calcium currents and had an undifferentiated morphology. When transplanted into the auditory nerves of rats in vivo, the cells migrated peripherally and centrally and aggregated to form coherent, ectopic ‘ganglia’. After 7 days they expressed β3‐tubulin and adopted a similar morphology to native spiral ganglion neurons. They also developed bipolar projections aligned with the host nerves. There was no evidence for uncontrolled proliferation in vivo and cells survived for at least 63 days. If cells were transplanted with the appropriate surgical technique then the auditory brainstem responses were preserved. We have shown that immortal cell lines can potentially be used in the mammalian ear, that it is possible to differentiate significant numbers of cells within the auditory nerve tract and that surgery and cell injection can be achieved with no damage to the cochlea and with minimal degradation of the auditory brainstem response.
Topographic distribution of output neurons in cerebellar nuclei and cortex to somatotopic map of primary motor cortex
Authors: Lu Xiaofeng , Miyachi Shigehiro , Ito Yumi , Nambu Atsushi , Takada Masahiko
Published: April 2007

To investigate the somatotopic organization of the cerebellum, we analysed multisynaptic inputs to the primary motor cortex (MI) using retrograde transneuronal transport of rabies virus. At 3 days after rabies injections into proximal forelimb, distal forelimb and hindlimb representations of the macaque MI, second‐order neurons via the thalamus were labeled in the deep cerebellar nuclei, including the dentate (DN), anterior interpositus (AIN) and posterior interpositus nuclei. In the DN, the labeling of both the forelimb and hindlimb was seen mainly in the dorsal aspect. The labeling of the hindlimb was located rostral to that of the forelimb and the labeling of the proximal forelimb was located slightly rostral to that of the distal forelimb. The same rostrocaudal arrangement was observed in the AIN. In the posterior interpositus nucleus, however, labeling from the MI hindlimb and forelimb representations largely overlapped. At the 4‐day postinjection period, third‐order labeling occurred in Purkinje cells of the cerebellar hemisphere. The Purkinje cell labeling from the forelimb representation, including the proximal and distal regions, was observed primarily in lobules IV–VI and crus I. The proximal forelimb labeling was both rostral and lateral to that of the distal forelimb within lobules IV–VI. However, the hindlimb labeling was seen both rostral and lateral to that of the proximal forelimb within lobules III–VI. These results indicate that the hindlimb, proximal forelimb and distal forelimb are arranged rostrocaudally in the DN and AIN, whereas there is dual somatotopy along the rostrocaudal and lateromedial axes in the cerebellar cortex.
Lesions of rat infralimbic cortex enhance renewal of extinguished appetitive Pavlovian responding
Authors: Rhodes S. E. V. , Killcross A. S.
Published: April 2007

It is well established that extinction is highly context dependent, and several behavioural phenomena associated with the expression of extinction (spontaneous recovery, reinstatement and renewal) have been described as resulting from this context dependency. It has previously been shown that lesions of the infralimbic (IL) region of the medial prefrontal cortex result in increased levels of spontaneous recovery and reinstatement of an extinguished appetitive Pavlovian conditioned response. The current study shows that lesions of the IL cortex also result in increased renewal of a conditioned response when tested in the acquisition context. Thirteen IL‐lesioned and 14 sham‐lesioned rats were trained on an appetitive Pavlovian task in one context (Context A) followed by extinction in a different context (Context B); animals were then tested for renewal of responding in both Context A and B. Both groups demonstrated similarly low levels of responding when tested in the extinction context (B), and greater responding (i.e. renewal) when tested in the acquisition context (A). Further, the level of response renewal was greater in IL‐lesioned animals. The results are discussed in relation to the possible role of the IL cortex in contextual control of extinction.
Constant light housing during nursing causes human DSPS (delayed sleep phase syndrome) behaviour in Clock‐mutant mice
Authors: Wakatsuki Yukako , Kudo Takashi , Shibata Shigenobu
Published: April 2007

Delayed sleep phase syndrome (DSPS) is very often seen among patients with sleep‐wake rhythm disorders. Humans with the 3111C allele of the human Clock gene tend to demonstrate a higher evening preference on the morningness–eveningness (ME) preference test. DSPS is thought to be an extreme form of this evening preference. Clock‐mutant mice have been proposed as an animal model of evening preference. In this study, we looked at whether constant light (LL) housing of Clock‐mutant mice during lactation would result in evening preference and/or DSPS. Housed under light–dark (LD) or constant dark (DD) conditions during the lactation period, both wild‐type and Clock‐mutant mice did not show a phase‐delay in the locomotor activity measured under light–dark conditions, whereas constant light housing during lactation significantly caused a delayed onset. The magnitude of the delay during the light–dark cycle was positively associated with free‐running period measured during constant darkness. Among wild, heterozygote, and homozygote pups born from heterozygous dams, only homozygote pups showed a delayed onset. Constant light–housed Clock‐mutant mice exhibited a lower number and delayed peak of phospho‐MAPK‐immunoreactive cells in core regions of the suprachiasmatic nucleus (SCN) compared to light–dark housed wild‐type or Clock‐mutant mice. Activity onset returned to normal with daily melatonin injection at the lights‐off time for 5 days. The present results demonstrate that Clock‐mutant mice exposed to constant light during lactation can function as an animal model of DSPS and can be used to gain an understanding of the ethological aspects of DSPS as well as to find medication for its treatment.
Illusory shape representation in the monkey inferior temporal cortex
Authors: Sáry Gy. , Chadaide Z. , Tompa T. , Köteles K. , Kovács GY. , Benedek G.
Published: April 2007

Perceived boundaries without physical differences between shape and background are called illusory contours (ICs). ICs and real contours (RCs) activate the early processing stages of the macaque visual pathway and the occipitotemporal areas of the human visual system in a similar way. However, it is not known how these contours are processed further in the highest visual areas. We tested how the responses of inferior temporal cortical (IT) neurons of macaque monkeys change in relationship to figures with RCs or ICs. The same set of figures [coloured pictures, ICs and silhouettes (SILs)] was presented to awake, fixating rhesus monkeys while the single‐cell activity was recorded in the anterior part of the IT. Most of the neurons responsive to RCs were also responsive to the same shapes presented as ICs. The average net firing rates, however, were significantly lower for the illusory stimuli than for the stimuli in the RC conditions, and the latency of the responses was significantly longer for the ICs than for the RCs. The shape selectivity was found to be different for coloured stimuli and ICs, and similar for SILs and ICs, suggesting the invariance of selectivity to shapes having the same contour but lacking internal surface information. These results suggest different modes of processing of RCs and ICs in the IT, which might explain the differences in their perception.
Emergence of topography in the developing hamster retinocollicular projection: axial differences and the role of cell death
Authors: Upton A. L. , Cordery P. M. , Thompson I. D.
Published: April 2007

The precise ordering of the hamster retinocollicular projection is established over the first two postnatal weeks, coincident with developmental cell death. We have used quantitative retrograde labelling to define topographic precision in the early postnatal projection, to describe its refinement and to assess the contribution played by selective retinal ganglion cell death. The hamster's short gestation period allows the investigation of events occurring prenatally in other rodents. Discrete injections of fluorescent beads in the superior colliculus followed by isodensity contour analysis of labelled retinal cells reveals a dramatic decrease in the extent of retina labelled between postnatal days 2, 6 and 12 (P2, P6, P12): the 20% contour encloses 38.3%, 8.3% and 1.8% of the retina at these ages. Paired injections of two different tracers at variable rostrocaudal (R–C) separations at P2 produced complete overlap of label even when injections were separated by over 1 mm. This was not true for paired mediolateral injections at P2 that were separated by more than 500 µm. Analysis of the segregation of the two tracers (‘nearest‐neighbour analysis’) shows topography improving with age so that by P12 injections separated rostrocaudally by more than 500 µm produced no overlap in the retina. To examine the contribution of selective ganglion cell death to topographic refinement, animals given paired R–C injections at P2 were allowed to survive until P12. Nearest‐neighbour analysis reveals significantly more order in the P2–P12 retinae than after overnight survival. Thus, selective cell death plays a small but appreciable role in correction of topographical errors.
The innervation of parvalbumin‐containing interneurons by VIP‐immunopositive interneurons in the primary somatosensory cortex of the adult rat
Authors: Dávid Csaba , Schleicher Axel , Zuschratter Werner , Staiger Jochen F.
Published: April 2007

γ‐Aminobutyric acid (GABA)ergic interneurons of neocortex consist of many subgroups with extremely heterogeneous morphological, physiological and molecular properties. To explore the putative effect of the vasoactive intestinal polypeptide‐immunopositive (VIP +) neurons on neocortical circuitry, the number and distribution of VIP + boutons were analysed on somatodendritic domains of 272 parvalbumin immunopositive (PV +) 3D‐reconstructed neurons. The synaptic nature of 91% of somatic and 76% of dendritic contacts was verified by electron microscopy. The target PV + neurons were separated in two significantly different groups by means of cluster analysis. The first group (Cluster 1, 26%) received on average five times more VIP + synapses than those of the second group. The second group (Cluster 2, 74%) contained cells that were poorly innervated by VIP + boutons or did not have either somatic or dendritic or any VIP innervation at all. The cells of Cluster 1 had a soma size and total dendritic length significantly smaller than that of Cluster 2, however, they received three times more dendritic synapses, which resulted in a five times higher VIP + synaptic density on dendrites. Our results showed that although most of the PV + cells are innervated by VIP + boutons at a varying degree, some 6% of PV + cells received no input from VIP + interneurons. This suggests a refined morphological basis to influence the majority of the PV + interneurons, which are very effectively controlling pyramidal cell firing. Together with metabolic and neuromodulatory effects of VIP, this would probably result in an enhanced responsiveness of the latter cell type to tactile stimuli.
Glycogen synthase kinase 3 activation is essential for the snake phospholipase A2 neurotoxin‐induced secretion in chromaffin cells
Authors: Giner Daniel , López Inmaculada , Ñeco Patricia , Rossetto Ornella , Montecucco Cesare , Gutiérrez Luis M.
Published: April 2007

Neuroendocrine chromaffin cells were used to study the mechanism of the snake phospholipase A2 (PLA2) neurotoxin enhancement of exocytosis. Notexin, β‐bungarotoxin, taipoxin or textilotoxin enhanced the fast release of catecholamines elicited by flash photolysis of cytosolic caged calcium. Such an increase correlates with the capacity of these neurotoxins to cause fragmentation of the F‐actin cortical barrier with subsequent accumulation of vesicles in the proximity of the plasma membrane. These PLA2 neurotoxins do not act via protein kinase C activation, which is known to promote F‐actin fragmentation. Lithium, RO31‐8220 and SB216763, three inhibitors of the glycogen synthase kinase 3, prevent both the alteration of the F‐actin peripheral cortex and the enhancement of fast release elicited by these neurotoxins. In addition, glycogen synthase kinase 3 has been detected by immunolocalization in a membranous compartment of the chromaffin cell endoplasmic reticulum (ER). These results suggest that the activation of this enzyme plays a major role in the enhancement of exocytosis of the readily releasable granules caused by PLA2 neurotoxins in neuroendocrine chromaffin cells.
Locomotor exercise alters expression of pro‐brain‐derived neurotrophic factor, brain‐derived neurotrophic factor and its receptor TrkB in the spinal cord of adult rats
Authors: Macias Matylda , Dwornik Anna , Ziemlinska Ewelina , Fehr Susanna , Schachner Melitta , Czarkowska‐Bauch Julita , Skup Malgorzata
Published: April 2007

Previous evidence indicates that locomotor exercise is a powerful means of increasing brain‐derived neurotrophic factor (BDNF) and its signal transduction receptor TrkB mRNA levels, immunolabeling intensity and number of BDNF‐ and TrkB‐immunopositive cells in the spinal cord of adult rats but the contribution of specific cell types to changes resulting from long‐term activity is unknown. As changes in BDNF protein distribution due to systemic stimuli may reflect either itsin‐situsynthesis or its translocation from other sources, we investigated where BDNF and TrkB mRNA are expressed in the spinal lumbar segments. We report on the cell types defined by size, BDNF mRNA levels and number of cells with TrkB transcripts in sedentary and exercised animals following 28 days of treadmill walking. In the majority of cells, exercise increased perikaryonal levels of BDNF mRNA but did not affect TrkB transcript levels. Bidirectional changes in a number of TrkB mRNA‐expressing cells occurred in small groups of ventral horn neurons. An increase in BDNF transcripts was translated into changes in pro‐BDNF and BDNF levels. A 7‐day walking regimen increased BDNF protein levels similarly to 28‐day treadmill walking. Our observations indicate that long‐ and short‐term locomotor activity of moderate intensity produce stimuli sufficient to recruit a majority of spinal cells to increased BDNF synthesis, suggesting that continuous tuning of pro‐BDNF and BDNF levels permits spinal networks to undergo trophic modulation not requiring changes in TrkB mRNA supply.
The neuroprotective effects of the Wlds gene are correlated with proteasome expression rather than apoptosis
Authors: Simonin Yannick , Ferrer‐Alcon Marcelino , Ferri Anna , Kato Ann C.
Published: April 2007

The Wlds gene (slow Wallerian degeneration) specifically delays axonal degeneration following injury and in several models of neurodegenerative diseases. It thus provides an interesting tool to study mechanisms of neurodegeneration. We previously crossed the Wlds mice with a mouse mutant that has a motoneuron disease (pmn for progressive motor neuronopathy) and showed that the Wlds gene prevented axonal loss, increased the life‐span and prolonged the survival of the motoneuron cell bodies. In this study we show that spinal motoneurons of pmn/pmn mice, as opposed to axons, die by apoptosis that cannot be prevented by the Wlds gene. However, this same gene could partially rescue the proteasome impairment observed in motoneuron cell bodies and axons of pmn/pmn mice. We conclude that the neuroprotective effect of the Wlds gene is not related to an inhibition of apoptosis but could possibly be linked to a regulation in proteasome expression.
Behavioral and neuroanatomical correlates of white matter asymmetries in chimpanzees (Pan troglodytes)
Authors: Hopkins William D. , Taglialatela Jared P. , Dunham Leslie , Pierre Peter
Published: April 2007

Although behavioral and brain asymmetries have been documented in non‐human primates, lateralization in cortical connectivity as reflected in white matter has not been described in any species, despite the intrinsic theoretical interest in white matter expansion during primate brain evolution. Here we report evidence of population‐level leftward asymmetries in the white matter of chimpanzees. We further report that lateralization in white matter correlates with their handedness as well as neuroanatomical asymmetries in the precentral gyrus. These findings suggest that chimpanzees show asymmetries in cortical connectivity and these may serve as the foundation for morphological and behavioral laterality in primates, including humans.
Neonatal functional blockade of the entorhinal cortex results in disruption of accumbal dopaminergic responses observed in latent inhibition paradigm in adult rats
Authors: Peterschmitt Y. , Meyer F. , Louilot A.
Published: April 2007

Latent inhibition (LI) has been found to be disrupted in non‐treated patients with schizophrenia. Dopaminergic (DAergic) dysfunctioning is generally acknowledged to occur in schizophrenia. Various abnormalities in the entorhinal cortex (ENT) have been described in patients with schizophrenia. Numerous data also suggest that schizophrenia has a neurodevelopmental origin. The present study was designed to test the hypothesis that reversible inactivation of the ENT during neonatal development results in disrupted DA responses characteristic of LI in adult rats. Tetrodotoxin (TTX) was microinjected locally in the left ENT at postnatal day 8 (PND8). DA variations were recorded in the dorsomedial shell and core parts of the nucleus accumbens (Nacc) using in vivo voltammetry in freely‐moving grown‐up rats in a LI paradigm. In the first session the animals were pre‐exposed (PE) to the conditional stimulus (banana odour) alone. In the second they were aversively conditioned to banana odour. In the third (test) session the following results were obtained in PE animals subjected to temporary inactivation of the ENT at PND8: (1) aversive behaviour was observed in TTX–PE conditioned animals; (2) DA variations in the dorsomedial shell and core parts of the Nacc were similar in TTX–PE and non‐pre‐exposed conditioned rats.

These findings strongly suggest that neonatal disconnection of the ENT disrupts LI in adult animals. They may further our understanding of the pathophysiology of schizophrenia.
Domain‐related differentiation of working memory in the Japanese macaque (Macaca fuscata) frontal cortex: a positron emission tomography study
Authors: Kojima T. , Onoe H. , Hikosaka K. , Tsutsui K. , Tsukada H. , Watanabe M.
Published: April 2007

The lateral prefrontal cortex (LPFC) is important for working memory (WM) task performance. Neuropsychological and neurophysiological studies in monkeys suggest that the lateral prefrontal cortex is functionally segregated based on the working memory domain (spatial vs. non‐spatial). However, this is not supported by most human neuroimaging studies, and the discrepancy might be due to differences in methods and/or species (monkey neuropsychology/physiology vs. human neuroimaging). We used positron emission topography to examine the functional segregation of the lateral prefrontal cortex of Japanese macaques (Macaca fuscata) that showed near 100% accuracy on spatial and non‐spatial working memory tasks. Compared with activity during the non‐working memory control tasks, the dorsolateral prefrontal cortex (DLPFC) was more active during the non‐spatial, but not during the spatial, working memory task, although a muscimol microinjection into the dorsolateral prefrontal cortex significantly impaired the performance of both working memory tasks. A direct comparison of the brain activity between the two working memory tasks revealed no differences within the lateral prefrontal cortex, whereas the premotor area was more active during the spatial working memory task. Comparing the delay‐specific activity, which did not include task‐associated stimulus/response‐related activity, revealed more spatial working memory‐related activity in the posterior parietal and premotor areas, and more non‐spatial working memory‐related activity in the dorsolateral prefrontal cortex and hippocampus. These results suggest that working memory in the monkey brain is segregated based on domain, not within the lateral prefrontal cortex but rather between the posterior parietal‐premotor areas and the dorsolateral prefrontal‐hippocampus areas.
Sensitivity to direction and orientation of random dot stereobars in the monkey visual cortex
Authors: Gonzalez Francisco , Romero Maria C. , Castro Adrian F. , Bermudez Maria A. , Perez Rogelio
Published: April 2007

We are able to judge the direction of movement and orientation of objects because they have contrast‐defined edges. However, we are also able to perceive the orientation and direction of movement of stereobars made of random dot stereograms in the absence of contrast‐defined edges. We recorded 207 disparity‐sensitive cells from visual areas V1 and V2 of two Macaca mulatta monkeys while performing an attentive fixation task. Luminance defined bars and random‐dot stereo‐defined bars were used to assess direction and orientation selectivity of these cells. Orientation and direction preference for luminance bars and for stereobars showed a statistically significant relationship (r = 0.83, P < 0.01 for direction; r = 0.63, P < 0.01 for orientation). However, disparity‐sensitive cells from these areas seem to be more sensitive to luminance than to stereobars regarding orientation and direction of movement. Similar results were obtained when the two areas were considered separately. Our results show that cells in areas V1 and V2 of the monkey visual cortex are able to detect the orientation and direction of movement of stereobars in a manner similar to those of luminance‐defined bars. This finding is relevant because to detect the direction and orientation of stereobars a comparison between left and right eye inputs is required.
Institutional investment flows and the determinants of top fund manager turnover
Authors: Dishi Elor , Gallagher David R. , Parwada Jerry T.
Published: April 2007

This study examines how the termination of superannuation investment mandates contributes to the departure of top fund managers in companies delegated the portfolio management role. Terminations of superannuation plan mandates increase the probability of a fund company changing the responsible fund manager. Objective‐adjusted returns are also significant managerial turnover considerations. These results illustrate that significant losses of superannuation fund clients act as an external control mechanism in the investment management industry that complements internal managerial performance measures.