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101.
Chronic unpredictable stress (CUS) was used to study the effects of a long-term treatment with either caffeine (8 mg/kg, orally) or desipramine (DMI) (10 mg/kg, intraperitoneally) in Wistar rats. The CUS procedure was applied for 6 weeks. Animals underwent a 2-week drug-free CUS procedure. Drugs were administered for 4 weeks alongside the stress and both drug and stress were continued throughout the behavioral testing period. CUS-exposed rats showed depressive-like behavior with reduced weight gain, reduced consumption of sucrose solution, increased immobility in the forced swimming test, and hypolocomotion in an open field. For the open field and elevated plus maze, calculation of an anxiety index confirmed that CUS increased anxiety, which was accompanied by an increase in the core temperature. DMI counteracted these physical and behavioral changes. Caffeine caused similar effects to DMI on weight gain, motor activity, anxiety level, and core temperature. In CUS-exposed rats, caffeine showed antidepressant and anxiolytic activity, accompanied by increased hippocampal dopamine and serotonin levels. However, no significant change in weight gain or core temperature was observed after caffeine treatment in CUS-exposed rats. These results suggest that, similar to the antidepressant DMI, long-term caffeine exposure exerts an antidepressant and anxiolytic effect in the CUS model. The involvement of the dopaminergic and serotonergic systems is discussed.  相似文献   
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Selectively breeding lines of mice and rats to differ in alcohol intake has proven useful for defining which traits correlate with high alcohol drinking behavior, as well as for creating animal models of alcoholism. This study reports the derivation of two novel sets of selected lines, High Alcohol Preferring (HAP) and Low Alcohol Preferring (LAP) replicate 2 and 3 lines. Mice were mass-selected using the same procedure as in the replicate 1 lines: using HS/Ibg as a progenitor, mice were selected for differences in 2-bottle choice intake of 10% alcohol during a 4-week testing period. In addition, another high-drinking line, the crossed HAP (cHAP) line was selectively bred from a progenitors that were a cross of replicate 1 (S27) × replicate 2 (S21) HAP lines. All lines were characterized for saccharin intake. Overall, the response to selection of the HAP and LAP replicate 2 and 3 lines was quite similar. As anticipated, following selection, the cHAP line drank more than either parent HAP line (consuming 26.0 g/kg per day of alcohol by S11), suggesting that this method of crossing replicate lines and selecting from that cross captures more alleles than any single selected line, as well as producing a line with exceptionally high voluntary alcohol intake. As expected, saccharin consumption was highly associated with alcohol consumption; data from 7 lines (HAP 1, 2, and 3, LAP 1, 2, and 3, and cHAP) indicated a genetic correlation between 10% alcohol and 0.32% saccharin intake of 0.91. Overall, these findings show the practicality of developing replicate lines divergent in alcohol preference, and validate a novel procedure for generating very high-drinking mouse populations.  相似文献   
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Objectives: To perform a psychometric evaluation of the Carers Assessment of Difficulties Index, Carers Assessment of Satisfactions Index and the Carers Assessment of Managing Index (CADI-CASI-CAMI).

Method: Data was collected in three European countries from informal carers of older people (n = 295) via a common protocol. Carers completed: (a) a questionnaire containing items on demographics and caregiving characteristics and (b) the CADI-CASI-CAMI indices. Principal component analysis of the CADI-CASI-CAMI indices was followed by internal consistency analysis of emergent components. Scales derived by summing items loading on the components were analysed for their association with the demographic and caregiving characteristic variables.

Results: CADI produced six internally consistent and interpretable components, CASI five and CAMI seven. Subscales derived from the components were significantly associated with the demographic and caregiving characteristic variables, providing initial support for construct validity.

Conclusion: The CADI-CASI-CAMI indices are recommended as an assessment tool for in-depth work with family carers of older people and as a research tool for large-scale studies of family care.  相似文献   

107.
Lack of conservation of the Amazon tropical rainforest has imposed severe threats to its human population living in newly settled villages, resulting in outbreaks of some infectious diseases. We conducted a seroepidemiological survey of 1100 inhabitants of 15 villages of Paço do Lumiar County, Brazil. Thirty‐five (3%) individuals had been exposed to Trypanosoma cruzi (Tc), 41 (4%) to Leishmania braziliensis (Lb) and 50 (4.5%) to Leishmania chagasi (Lc) infections. Also, 35 cases had antibodies that were cross‐reactive against the heterologous kinetoplastid antigens. Amongst these, the Western blot assays revealed that 11 (1%) had Tc and Lb, that seven (0.6%) had Lc and Tc, and that 17 (1.6%) had Lb and Lc infections. All of these cases of exposures to mixed infections with Leishmania sp, and eight of 11 cases of Tc and Lb were confirmed by specific PCR assays and Southern hybridizations. Two cases had triple infections. We consider these asymptomatic cases showing phenotype and genotype markers consistent with mixed infections by two or more kinetoplastid flagellates a high risk factor for association with Psychodidae and Triatominae vectors blood feeding and transmitting these protozoa infections. This is the first publication showing human exposure to mixed asymptomatic kinetoplastid infections in the Amazon.  相似文献   
108.
OBJECTIVE: Enhanced lipid peroxidation is well established in traumatic brain injury. However, its molecular targets, identity of peroxidized phospholipid species, and their signaling role have not been deciphered. METHODS: Using controlled cortical impact as a model of traumatic brain injury, we employed a newly developed oxidative lipidomics approach to qualitatively and quantitatively characterize the lipid peroxidation response. RESULTS: Electrospray ionization and matrix-assisted laser desorption/ionization mass spectrometry analysis of rat cortical mitochondrial/synaptosomal fractions demonstrated the presence of highly oxidizable molecular species containing C(22:6) fatty acid residues in all major classes of phospholipids. However, the pattern of phospholipid oxidation at 3 hours after injury displayed a nonrandom character independent of abundance of oxidizable species and included only one mitochondria-specific phospholipid, cardiolipin (CL). This selective CL peroxidation was followed at 24 hours by peroxidation of other phospholipids, most prominently phosphatidylserine, but also phosphatidylcholine and phosphatidylethanolamine. CL oxidation preceded appearance of biomarkers of apoptosis (caspase-3 activation, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-positivity) and oxidative stress (loss of glutathione and ascorbate). INTERPRETATION: The temporal sequence combined with the recently demonstrated role of CL hydroperoxides (CL-OOH) in in vitro models of apoptosis suggest that CL-OOH may be both a key in vivo trigger of apoptotic cell death and a therapeutic target in experimental traumatic brain injury.  相似文献   
109.
BACKGROUND AND AIMS: The rates of fibrosis progression in chronic hepatitis C are significantly different between males and females. The antifibrogenic effect of oestrogen has been proposed, possibly via inhibition of stellate cells. The aim of this study was to evaluate the severity of chronic hepatitis C in women, in relation to the menopause, steatosis and hormone replacement therapy (HRT). METHODS: From November 2003 to October 2004, women with chronic hepatitis C were enrolled prospectively. A questionnaire was completed prospectively and a blood sample was obtained on the day of biopsy. We identified characteristics associated with moderate/severe fibrosis using univariate and multivariate analysis. RESULTS: 251 women were included in the study. 122 women (52%) were menopausal and 65 were receiving HRT. 61 (24%) women with moderate/severe fibrosis (F2-F4, Metavir score) had a longer known duration of infection (>15 years), a higher body mass index and presented with steatosis more frequently than 190 (76%) women with mild fibrosis (F0-F1). Women with F2-F4 were more often menopausal (67% v 47%). The probability of fibrosis F2-F4 was lower for menopausal women receiving HRT (p = 0.012). Steatosis was more frequent and more severe in menopausal women. CONCLUSIONS: Severity of fibrosis was associated with a longer duration of infection (>15 years), a higher body mass index, advanced steatosis and the menopause. Menopausal women receiving HRT presented with a lower stage fibrosis. These results reinforce the hypothesis of a protective role of oestrogens in the progression of fibrosis. Steatosis may be implicated in the progression of fibrosis after the menopause.  相似文献   
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Toxoplasmosis is a well recognized manifestation of AIDS, but the disseminated disease is a rare condition and it has not been associated to HIV seroconversion to our knowledge. We describe a fatal episode of disseminated T. gondii acute infection with massive organ involvement during primary HIV infection. The serological data demonstrate primary T. gondii infection. The avidity index for HIV antibodies supports recent HIV-1 infection.  相似文献   
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