Miracle-dz/UniFAR-FTUs huggingface dataset:
Recollection is impaired, but familiarity remains intact in rats with lesions of the fornix

It has been argued that a neural system including the hippocampus, fornix, mamillary bodies, and anterior thalamus is specifically involved in recollection, but not in familiarity based memory processes. Here we test this hypothesis using a task of episodic‐like memory within an E‐shaped maze. Animals seek out a preferred object (what) in a particular location (where) that is unique to a particular context (which occasion). As objects are hidden from view at the point of decision making, the animals can only base their decision on recall of their previous episode in the E‐shaped maze. In contrast, once a decision has been made animals are free to explore both objects and display an object preference when objects are visible to the animal and decisions can be made on the basis of familiarity. Animals with fornix lesions are impaired at recalling a past event. However, the same animals on the same trials show no such impairment in a judgement of familiarity. We therefore demonstrate that recall is dependent upon the fornix, while familiarity based memory is not. © 2009 Wiley‐Liss, Inc.
Increased hippocampal neurogenesis in the progressive stage of Alzheimer's disease phenotype in an APP/PS1 double transgenic mouse model

Alzheimer's disease (AD) is a progressive neurodegenerative disease associated with senile β‐amyloid (Aβ) plaques and cognitive decline. Neurogenesis in the adult hippocampus is implicated in regulating learning and memory, and is increased in human postmortem brain of AD patients. However, little is currently known about the changes of hippocampal neurogenesis in the progression of AD. As brain tissues from patients during the progression of AD are generally not available, an amyloid precursor protein (APP)/presenilin1 (PS1) double transgenic mouse model of AD was studied. Bromodeoxyuridine (BrdU) labeling supported by doublecortin staining was used to detect proliferating hippocampal cells in the mice. Compared with age‐matched wild‐type controls, 9‐month‐old transgenic mice with memory impairment and numerous brain Aβ deposits showed increased numbers of proliferating hippocampal cells. However, 3‐month‐old transgenic mice with normal memory and subtle brain Aβ deposits showed normal hippocampal proliferation. Double immunofluorescent labeling with BrdU and either NeuN or glial fibrillary acidic protein was conducted in mice at 10 months (28 days after the last BrdU injection) to determine the differentiation of proliferating cells. The number of hippocampal BrdU‐positive cells and BrdU‐positive cells differentiating into neurons (neurogenesis) in 10‐month‐old mice was greater in transgenic mice compared with age‐matched controls, but the ratio of hippocampal BrdU‐positive cells differentiating into neurons and astroglia was comparable. These results suggest hippocampal neurogenesis may increase during the progression of AD. Targeting this change in neurogenesis and understanding the underlying mechanism could lead to the development of a new treatment to control the progression of AD. © 2009 Wiley‐Liss, Inc.
Quantitative changes in hippocampal microvasculature of chronically stressed rats: No effect of fluoxetine treatment

Exposure to chronic stress alters the number and morphology of neurons and glia in the hippocampal formation; however, little is known about possible changes in vasculature. Here, we examined the effect of chronic social defeat stress on hippocampal vascular supply in rats. Recent reports document that antidepressant treatment can influence angiogenesis in the hippocampus; therefore, we also studied the effect of antidepressant drug treatment on hippocampal capillarization. Animals were subjected to 5 weeks of daily social defeat by an aggressive conspecific and received concomitant, daily, oral fluoxetine (10 mg/kg) treatment during the last 4 weeks. Rat endothelial cell antigen‐1 (RECA‐1)‐labeling of capillaries and quantitative stereological techniques were used to evaluate the treatment effects on capillary number. Special attention was paid to analysis of the vascular supply of the subgranular zone, which is regarded as an important component of the neurogenic niche for adult hippocampal neurogenesis. Chronic stress significantly decreased the number of microvessels by 30% in all hippocampal subregions, whereas fluoxetine treatment had no influence on capillary number. Furthermore, chronic stress decreased the capillarization of the subgranular zone to a similar extent, indicating that chronic stress affects the vascular niche for adult hippocampal neurogenesis. However, fluoxetine treatment had no impact on capillarization in the subgranular zone. We also detected a decrease in hippocampal volume in the animals as a result of stress, which was mildly altered by fluoxetine treatment. These pronounced changes in vascular supply may explain why the hippocampus is more vulnerable to insults when chronic stress precedes or coincides with other harmful conditions. Reduced microvasculature may also contribute to hippocampal volume decrease in stress‐related disorders. © 2009 Wiley‐Liss, Inc.
Selective effect of age, Apo e4, and Alzheimer's disease on hippocampal subfields

Histopathological studies and animal models suggest that different physiological and pathophysiological processes exert different subfield specific effects on the hippocampus. High‐resolution images at 4T depict details of the internal structure of the hippocampus allowing for in vivo volumetry of hippocampal subfields. The aims of this study were (1) to determine patterns of hippocampal subfield volume loss due to normal aging and Apo e4 carrier state, (2) to determine subfield specific volume losses due to preclinical (MCI) and clinical Alzheimer's disease (AD) and their modification due to age and Apo e4 carrier state. One hundred fifty seven subjects (119 cognitively healthy elderly controls, 20 MCI and 18 AD) were studied with a high resolution T2 weighted imaging sequence obtained at 4T aimed at the hippocampus. Apo e4 carrier state was known in 95 subjects (66 controls, 14 MCI, 15 AD). Subiculum (SUB), CA1, CA1‐CA2 transition zone (CA1‐2 transition), CA3‐ dentate gyrus (CA3&DG) were manually marked. Multiple linear regression analysis was used to test for effects of age, Apo e4 carrier state and effects of MCI and AD on different hippocampal subfields. Age had a significant negative effect on CA1 and CA3&DG volumes in controls (P < 0.05). AD had significantly smaller volumes of SUB, CA1, CA1‐2 transition, and MCI had smaller CA1‐2 transition volumes than controls (P < 0.05). Apo e4 carrier state was associated with volume loss in CA3&DG compared to non‐Apo e4 carriers in healthy controls and AD. Based on these findings, we conclude that subfield volumetry provides regional selective information that allows to distinguish between different normal and pathological processes affecting the hippocampus and thus for an improved differential diagnosis of neurodegenerative diseases affecting the hippocampus. © 2009 Wiley‐Liss, Inc.
Measuring children's self-efficacy and proxy efficacy related to fruit and vegetable consumption.

BACKGROUND Social cognitive theory describes self-efficacy and proxy efficacy as influences on fruit and vegetable consumption (FVC). Proxy efficacy was defined as a child's confidence in his or her skills and abilities to get others to act in one's interests to provide fruit and vegetable (FV) opportunities. The purpose of this study was to develop a scale assessing children's self-efficacy and proxy efficacy for FVC at after-school programs and at home. METHODS Elementary-aged children (n = 184) attending 7 after-school programs completed a self-efficacy questionnaire relevant to FVC. Questionnaire validity was investigated with exploratory factor analysis and mixed-model analysis of covariance. Internal consistency reliability and readability were also assessed. RESULTS The questionnaire assessed 4 constructs: self-efficacy expectations for fruit consumption, self-efficacy expectations for vegetable consumption, proxy efficacy to influence parents to make FV available, and proxy efficacy to influence after-school staff to make FV available. Children perceiving FV opportunities in after-school had greater self-efficacy expectations for FVC and greater proxy efficacy to influence after-school staff compared to students who did not perceive FV opportunities. Children attending schools of higher socioeconomic status (SES) and less diversity were more confident they could influence their parents to make FV available than students attending lower SES and less diverse schools. Adequate internal consistency and test-retest reliabilities were established. CONCLUSIONS Self-efficacy is a multicomponent construct that can be assessed in children using the reliable and valid instrument evaluated by the current study.
Racial, ethnic, and sex differences in the associations between violence and self-reported health among US high school students.

BACKGROUND Involvement in interpersonal violence or suicidal behaviors can have a significant impact on an adolescent's physical health. Similarly, previous research has suggested that lived experiences, more than the presence or absence of physical ailments, can significantly influence self-assessed health status among adolescents. The purpose of this study was to examine the cross-sectional associations between involvement in violence and poor or fair self-reported health among US high school students. METHODS Data were obtained from the 2005 national Youth Risk Behavior Survey (n = 13,953). Logistic regression analyses were conducted to determine the associations between violence-related measures and self-reported health while controlling for demographic characteristics and potential confounders. Analyses are presented for students overall and stratified by sex and race/ethnicity. RESULTS Overall, 7.2% of students reported fair or poor self-rated health. Having been in a physical fight, having been injured in a physical fight, having attempted suicide, and having not gone to school because of safety concerns were significantly associated with fair or poor self-rated health after controlling for demographic characteristics and other potential confounders. Differences associated with race/ethnicity and sex are identified. CONCLUSIONS Four of the 5 violence-related measures included in these analyses were significantly associated with fair or poor self-rated health. Future studies should consider the impact of involvement in violent behaviors and perceptions of both physical and mental well-being.
Opioid withdrawal for 4 days prevents synaptic depression induced by low dose of morphine or naloxone in rat hippocampal CA1 area in vivo

The formation of memory is believed to depend on experience‐ or activity‐dependent synaptic plasticity, which is exquisitely sensitive to psychological stress since inescapable stress impairs long‐term potentiation (LTP) but facilitates long‐term depression (LTD). Our recent studies demonstrated that 4 days of opioid withdrawal enables maximal extents of both hippocampal LTP and drug‐reinforced behavior; while elevated‐platform stress enables these phenomena at 18 h of opioid withdrawal. Here, we examined the effects of low dose of morphine (0.5 mg kg−1, i.p.) or the opioid receptor antagonist naloxone (1 mg kg−1, i.p.) on synaptic efficacy in the hippocampal CA1 region of anesthetized rats. A form of synaptic depression was induced by low dose of morphine or naloxone in rats after 18 h but not 4 days of opioid withdrawal. This synaptic depression was dependent on both N‐methyl‐D‐aspartate receptor and synaptic activity, similar to the hippocampal long‐term depression induced by low frequency stimulation. Elevated‐platform stress given 2 h before experiment prevented the synaptic depression at 18 h of opioid withdrawal; in contrast, the glucocorticoid receptor (GR) antagonist RU38486 treatment (20 mg kg−1, s.c., twice per day for first 3 days of withdrawal), or a high dose of morphine reexposure (15 mg kg−1, s.c., 12 h before experiment), enabled the synaptic depression on 4 days of opioid withdrawal. This temporal shift of synaptic depression by stress or GR blockade supplements our previous findings of potentially correlated temporal shifts of LTP induction and drug‐reinforced behavior during opioid withdrawal. Our results therefore support the idea that stress experience during opioid withdrawal may modify hippocampal synaptic plasticity and play important roles in drug‐associated memory. © 2009 Wiley‐Liss, Inc.
Progesterone Promotes the Survival of Newborn Neurons in the Dentate Gyrus of Adult Male Mice

This study investigated the effects of progesterone (P4) on the production and survival of neurons in the hippocampal dentate gyrus of adult male mice. The administration of P4 (4 mg/kg) for 3 consecutive days beginning on the 0–2nd day after the first BrdU-injection (BrdU-D0–2) produced an approximately twofold increase in the number of 28and 56-day-old BrdU cells in comparison to the controls, whereas it did not alter the number of 24/48-h-old BrdU cells. P4 preferentially promoted the survival of newborn neurons when administered at BrdU-D5–7, but not at BrdU-D10–12 and BrdU-D15–17. Androstenedione (Ad), testosterone (TE), or estradiol (E2) at the same-dose of P4, when administered at BrdU-D0–2, could not replicate the effect of P4, while the inhibition of 5a-reductase by finasteride did not affect the P4action, indicating that the P4-effect is exerted by P4 itself but not by its metabolites. On the other hand, the P4R antagonist RU486 partially suppressed the P4-effect, while inhibitors for Src, MEK, or PI3K totally suppressed the P4-effect. Finally, the P4-enhanced survival of newborn neurons was accompanied by a potentiation of spatial learning and memory, which was P4R-dependent. These findings suggest that P4 enhances the survival of newborn neurons through P4R and/or the SrcERK and PI3K pathways independent of its influence on cell proliferation, which is well correlated with the potentiated spatial cognitive function of P4-treated animals. VC 2009 Wiley-Liss, Inc.
Escore para rastrear idosos (> 75 anos) de alto risco para doença arterial periférica

BACKGROUND: The prevalence of peripheral arterial disease (PAD) in the elderly is high. Most are asymptomatic and the sensitivity of the physical exam is low. In Brazil, little is known in regard to PAD risk factors in the elderly. OBJECTIVES: To identify risk factors for PAD among elderly individuals (> 75 years) in the community and to develop a prediction score. METHODS: Cross-sectional, prospective, community-based study nested within a cohort study ("Epidoso"). A total of 176 individuals were assessed. PAD was defined as an ankle-brachial index 18 points defined the "high risk" individuals and yielded sensitivity, specificity, positive predictive value and negative predictive value of 85.9%, 71.4%, 63.2% and 89.9%, respectively. Receiver-operator characteristic analysis yielded area under curve of 85%, indicating excellent discrimination and goodness-of-fit statistics indicated excellent calibration (p=0.639). CONCLUSION: Because of its good performance, the proposed score can become a simple and useful tool to identify elderly community residents at higher risk of PAD who should be considered for further investigation.
Selective populations of hippocampal interneurons express ErbB4 and their number and distribution is altered in ErbB4 knockout mice

Neuregulins (NRGs) are ligands of ErbB receptor tyrosine kinases. The NRG1‐ErbB4 pathway has been shown to modulate hippocampal synaptic plasticity and network oscillations in the adult rodent brain. To identify cells that mediate these effects, here we determine the expression pattern of ErbB4 in four functionally distinct classes of interneurons that represent the majority of all inhibitory neurons in the adult hippocampus. On the basis of data from nine mice and 25,000 cells, we show that ErbB4 is expressed in cells that are positive for cholecystokinin (CCK, 54%), parvalbumin (PV, 42%), or neuronal nitric oxide synthase (nNOS, 39%) in a layer‐specific and region‐specific manner, whereas cells expressing somatostatin (SOM) are rarely immunoreactive for ErbB4 (1%). We next compared the numerical density (cells/mm3) and the distribution of interneurons between ErbB4−/− mice and wildtype controls. Based on data from 25 mice and 56,000 cells, we detected reductions of PV‐positive and nNOS‐positive cells in knockouts (−24% and −27%, respectively) but only a minor reduction of CCK‐positive cells; no changes in SOM‐positive cells were observed. The overall reduction of interneurons was verified by quantification of GAD67‐immunoreactive cells (−24% in ErbB4−/− mice). The reduction of interneurons along the dorsoventral axis was more severe in intermediate and ventral portions than in the dorsal hippocampus, and regional reductions occurred in the CA1–3 regions and subiculum, whereas we found no significant changes in the dentate gyrus (DG). The expression by different populations of interneurons suggests that ErbB4 can modulate several microcircuits within the hippocampus and mediate the previously reported effects of NRG1 on network oscillations and synaptic plasticity. The selective reduction of GABAergic cells in ErbB4−/− mice is consistent with the role of NRG‐ErbB4 signaling in the generation and migration of interneurons during development, and with neuronal and behavioral functional deficits in adult ErbB4 knockouts. © 2009 Wiley‐Liss, Inc.
Factors facilitating and constraining the scaling up of an evidence-based strategy of community-based primary care: Management perspectives from northern Ghana

From 1994 to 2003, the government of Ghana investigated the child survival and fertility impacts of community-based primary care nurses and volunteer mobilisation efforts. This study, known as the Navrongo Project, demonstrated improved health outcomes and was scaled-up as the Community-based Health Planning and Services (CHPS) Initiative. Studies suggest that scaled-up CHPS services have not fully replicated the impact of the Project. This study investigates implementation challenges that could explain this atrophy by assembling the perspectives of health care managers that have experience with both the Project and CHPS. Data from in-depth interviews of health managers are analysed using deductive content analysis. Respondents exhibited a consistent vision of doorstep services with regard to the Project and CHPS. They shared the perspective that while scale-up has progressed slowly, it has expanded the range of services provided. Respondents felt, however, that the original emphasis on community involvement has atrophied with scale-up and that current operations are managed less rigorously than during the Project. Thus, while the expanded scope of CHPS has increased access to health care, the original focus on community engagement has faded. The original Project leadership strategy merits review for ways to integrate leadership development into scale-up activities.
Causal evidence for the involvement of the neural cell adhesion molecule, NCAM, in chronic stress‐induced cognitive impairments

In rodents, chronic stress induces long‐lasting structural and functional alterations in the hippocampus, as well as learning and memory impairments. The neural cell adhesion molecule (NCAM) was previously hypothesized to be a key molecule in mediating the effects of stress due to its role in neuronal remodeling and since chronic stress diminishes hippocampal NCAM expression in rats. However, since most of the evidence for these effects is correlative or circumstantial, we tested the performance of conditional NCAM‐deficient mice in the water maze task to obtain causal evidence for the role of NCAM. We first validated that exposure to chronic unpredictable stress decreased hippocampal NCAM expression in C57BL/6 wild‐type mice, inducing deficits in reversal learning and mild deficits in spatial learning. Similar deficits in water maze performance were found in conditional NCAM‐deficient mice that could not be attributed to increased anxiety or enhanced corticosterone responses. Importantly, the performance of both the conditional NCAM‐deficient mice and chronically stressed wild‐type mice in the water maze was improved by post‐training injection of the NCAM mimetic peptide, FGLs. Thus, these findings support the functional involvement of NCAM in chronic stress‐induced alterations and highlight this molecule as a potential target to treat stress‐related cognitive disturbances. © 2009 Wiley‐Liss, Inc.
Resisting the binarism of victim and agent: Critical reflections on 20 years of scholarship on young women and heterosexual practices in South African contexts

The last 20 years have seen a proliferation of research, spurred by the imperatives of the HIV epidemic and reportedly high rates of gender-based violence, on heterosexual practices in the South African context. Research has focused on how poverty, age and gender within specific cultural contexts shape sexual agency and provide a context for unequal, coercive and violent practices for young women. This paper takes stock of what we currently ‘know’ about heterosex and critically reflects on the political and ideological effects of such research, specifically in the light of young women's agency. A primary concern is that efforts to address gender inequality and the normative gender practices that shape inequitable heterosexual practices may have functioned to reproduce the very discourses that underpin such inequalities. The paper ‘troubles’ the victim–agency binarism as it has been played out in South African research on heterosex, raising concerns about how the research may reproduce gendered, classed and raced othering practices and discourses and bolstered regulatory and disciplinary responses to young women's sexualities. The paper argues for critical, feminist self-reflexivity that should extend to re-thinking methodologies entrenched in frameworks of authority and surveillance.
Gender does not moderate hippocampal volume deficits in adults with posttraumatic stress disorder: A meta‐analysis

Epidemiological studies show a higher point prevalence of posttraumatic stress disorder (PTSD) in women than in men, and early evidence has suggested that gender may moderate hippocampal volume deficits in PTSD. Our objective was to use random‐effects meta‐regression to assess gender effects on hippocampal volume deficits in PTSD. Using the terms posttraumatic stress disorder, gender, MRI, hippocampus, trauma, and abuse, we searched electronic databases for peer‐reviewed articles up to April 2009 containing data for hippocampal volume and gender composition in PTSD adults compared with controls. We identified 23 studies that met inclusion criteria and calculated effect sizes for differences in hippocampal mean volumes for each study and used the percentage of men with PTSD as a continuous moderating variable in meta‐regression. Additionally, we did a subgroup analysis of hippocampal volume deficits between women and men with gender as a categorical moderating variable. Hippocampal volumes were significantly smaller in the PTSD group compared to the control group, but gender did not significantly moderate any effect sizes in the meta‐regression or subgroup analyses. The lack of gender moderation on hippocampal volume deficits suggests that hippocampal volume deficits in PTSD are independent of gender. The higher prevalence of PTSD in females than in males does not correspond to increased hippocampal volume deficits in women with PTSD compared to men with PTSD, and neither gender appears protective against hippocampal volume deficits in adults with PTSD. © 2011 Wiley‐Liss, Inc.