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1.
Post mortem brain studies indicate that alterations in serotonergic and catecholaminergic systems might be associated with Alzheimer's disease (AD). The aim of the study was to determine serotonin (5-HT) levels and monoamine oxidase type B (MAO-B) activity in platelets of psychotic and non-psychotic patients with AD, established according to the NINCDS-ADRDA and DSM-IV-TR criteria. Cognitive impairment and psychotic features were evaluated using Mini Mental Status Examination and Neuropsychiatric Inventory. Platelet 5-HT concentration and MAO-B activity were determined spectrofluorimetrically in 116 (51 male, 65 female) healthy subjects and 70 psychotic (10 male, 60 female) and 151 non-psychotic (32 male, 119 female) patients. Psychotic and non-psychotic female and psychotic male patients had significantly lower platelet 5-HT concentration than corresponding sex matched control subjects. Platelet MAO-B activity was significantly increased in both male and female non-psychotic patients compared to the sex matched controls. Non-psychotic female patients had significantly higher platelet MAO-B activity than psychotic female patients. Our data suggest that platelet MAO-B activity, but not platelet 5-HT concentration, could differentiate between psychotic and non-psychotic subtypes of AD.  相似文献   

2.
Subclinical psychotic experiences at the level of the general population are common, forming an extended psychosis phenotype with clinical psychosis. Persistence of subclinical experiences is associated with transition to later mental disorder. Increased daily life stress reactivity is considered an endophenotype for psychotic disorders. We examined, in a longitudinal framework, whether baseline momentary assessment markers of stress reactivity would predict persistence of subclinical psychotic experiences over time. In a general population sample of female twins (N = 566), the Experience Sampling Method (ESM; repetitive random sampling of momentary emotions, psychotic experiences and context) was used to assess (emotional and psychotic) daily life stress reactivity. Persistence of subclinical psychotic experiences was based on the Community Assessment of Psychic Experiences (CAPE), assessed three times over 14 months post-baseline. It was investigated whether baseline daily life emotional and psychotic stress reactivity predicted persistence of psychotic experiences over time. Higher levels of emotional stress reactivity (a decrease in positive and an increase in negative affect in response to stress), and increased psychotic reactivity to daily stress was found in individuals with persistent psychotic experiences over time compared to individuals with transient psychotic experiences. The results suggest that markers of daily life stress reactivity may predict “macro-level” persistence of normally transient expression of psychotic liability over time. Linking daily life markers of altered reactivity in terms of emotions and psychotic experiences to longitudinal persistence of psychotic experiences, associated with increased risk of transition to overt mental disorder, may contribute to earlier and more accurate diagnosis of risk.  相似文献   

3.
The female sex pheromone of Rhizoglyphus setosus Manson (Astigmata: Acaridae) was identified as S-isorobinal (4S-4-isopropenyl-3-oxo-1-cyclohexene-1-carboxyaldehyde), which stimulated males sexually and enhanced the frequency of the male’s tapping and mounting behavior. Although the female hexane extract indicated no sign of sex pheromone activity against tested males, possibly due to the presence of the alarm pheromone neryl formate, an SiO2 column fraction containing isorobinal elicited sex pheromone activity at a dose of one female equivalent. The stereochemistry of natural isorobinal was identified as S by an HPLC using a chiral column. Both S- and R-isorobinals exhibited maximum activity at the same dose of 1 and 10 ng with a convex dose–response relationship. Amounts of S-isorobinal were determined to be 11.7 ± 1.0 ng per female and 6.4 ± 1.3 ng per male by GLC. This is the second example of two pheromones (the alarm pheromone neryl formate, and the sex pheromone S-isorobinal) demonstrated to be components of the same opisthonotal gland secretion.Chemical ecology of astigmatid mites. LXXVIII  相似文献   

4.
Berk M  Plein H  Belsham B 《Life sciences》2000,66(25):2427-2432
Hypoglutamatergic function is implicated in the pathogenesis of schizophrenia, and supersensitivity of platelet NMDA receptors has been reported in schizophrenia. The aim of this study was to examine the platelet glutamate receptor sensitivity in patients with schizophrenia (n=12), mania with psychotic features (n=10) and depression with psychotic features (n=10) and matched controls (n=12) in order to assess if this is a marker of schizophrenia or occurs in other psychotic conditions. Glutamate receptor sensitivity was assessed using the intracellular calcium response to glutamate measured with spectrofluorometry. The percentage response of the schizophrenic and depressed psychotic subjects to glutamate stimulation was significantly greater than control subjects (p<0.005). The mania with psychotic features group was not significantly different to controls. This data suggests that platelet glutamate receptors may be supersensitive in schizophrenia and depression with psychotic features. Furthermore, the platelet may be a possible peripheral marker of glutamate function in schizophrenia and depression with psychotic features.  相似文献   

5.
It was observed that in the female gametophyte of Undaria pinnatifida (Harv.) Suringar (Phaeophyta, Laminariales) gametangial initials and maturing oogonia demonstrated different levels of alkaline‐phosphatase activity (APA). The oogonia exhibited a higher level of APA than in its initials. Electron‐dense granular ovoid structures ~0.5–0.6 μm were present in the cytoplasm of oogonia. These inclusions were not membrane bound and do not appear to be associated with any particular organelles. The number of the inclusions was 1 to 2 in a single section of the cell. In essential details, the specific APA and subcellular germinal body‐like structure of the developing female gamete in U. pinnatifida were very similar to those in metazoan oocytes.  相似文献   

6.
In species where males and females interact during mating, the role of females in sexual selection cannot always be demonstrated unambiguously. Here we present a model system to study female choice for mates. Orchesella cinca is a soil-dwelling hexapod with indirect sperm transfer. Females and males do not interact physically for reproduction. We gave females the choice between spermatophores produced by two different males. Paternity analysis based on microsatellite variation revealed that offspring in one clutch were sired by one male only. Direct observations showed that after a female has taken up a spermatophore, the female's receptivity to further spermatophore uptake seem to end. Our results imply that the female is in full control of paternity.  相似文献   

7.
Emil Kraepelin would clearly recognize his 19th century dichotomy within current operational classifications of psychosis. However, he might be surprised at its survival, given the extent to which it has been undermined by the weight of currently available empirical evidence. The failure of this evidence to influence diagnostic practice reflects not only the comfortable simplicity of the dichotomous approach, but also the fact that this approach has for many years continued to receive support from some areas of research, particularly genetic epidemiology. This, however, is changing and findings from genetic epidemiology are being reappraised. More importantly, the potential of molecular genetics to indicate biological systems involved in psychopathology has been recognized, and with it the potential to develop diagnostic classifications that have greater biological validity. Crucially, this will facilitate diagnostic schemes with much greater clinical utility, allowing clinicians to select treatments based on underlying pathogenesis. Recent molecular genetic findings have demonstrated very clearly the inadequacies of the dichotomous view, and highlighted the importance of better classifying cases with both psychotic and affective symptoms. In this article we discuss these issues and suggest ways forward, both immediately and for DSM-V and ICD-11. If psychiatry is to translate the opportunities offered by new research methodologies, we must move to a classificatory approach that is worthy of the 21st century.  相似文献   

8.
In the black chafer Holotrichia kiotonensis Brenske (Coleoptera: Scarabaeidae), mating behavior was observed between 1940 and 2010 hours at < 0.1 lx in both the laboratory and the field. In the laboratory, an ether extract of female abdominal glands induced a series of pre-mating behaviors such as short-distance orientation and abdominal bending. When the extract was fractionated by silica gel column chromatography, the active fraction was eluted with 50% ether in hexane and 100% ether. Gas chromatography–mass spectrometry analysis revealed that both active fractions contained anthranilic acid (2-amino-benzoic acid) as a major compound. The amount of this compound was determined to be ca. 600 ng/female by high performance liquid chromatography analysis with a fluorescence detector. In the field, male chafers were observed to land on cotton balls impregnated with 10 mg of authentic anthranilic acid. When a white ball treated with anthranilic acid was placed 2–10 cm away from an untreated black ball, males were observed to land significantly more frequently on the latter. These results suggest that males could recognize white balls below 0.1 lx and landed on black balls. When a treated black ball was placed beside an untreated black ball, more males landed on the former. The difference was significant when the distance between the two lures was 5 or 10 cm, but not significant when it was 2 cm. These observations demonstrated that anthranilic acid was the sex-attractant pheromone for the black chafer H. kiotonensis and that the males located and landed on a pheromone source by using olfaction in conjunction with visual orientation. The importance of visual orientation in this nocturnal species is discussed in comparison with the congeneric diurnal species Holotrichia loochooana loochooana.  相似文献   

9.
10.
Clinical and laboratory features of seven patients with acute leukemia associated with the (4;11) chromosome translocation are presented. Leukemic blasts of these patients showed lymphoid morphology in 6 (although 1 was treated for monoblastic leukemia 3 years earlier) and monocytoid morphology in 1, were positive for TdT and HD 37 (CD 19) in 6 patients, whereas weak expression of CALLA was seen in only 1 patient and T-lineage-associated antigens in none. Leukemic blasts from four patients showed the simultaneous expression of B-lymphoid and myeloid antigens, suggesting leukemogenesis in a very early multipotent progenitor cell. In 2 patients an isochromosome of the long arm of No. 7 chromosome was found in the leukemic karyotypes in addition to t (4; 11) (q 21; q 23); in one instance present at diagnosis, in the other one occurring at relapse. In one other patient leukemia karyotype also demonstrated trisomy 8. Leukemic cells of three patients were investigated by molecular genetics and demonstrated immunoglobulin gene rearrangements for the Ig heavy chain sequences but not for the light chain constant regions and T cell receptor sequences. All patients were treated by intensive chemotherapy. Four of the 7 patients are in continuous complete remission. The longest event-free survival time (over 2 1/2 years) was seen in one patient who had also DOWN-syndrome. Including these 7 patients a clinical analysis of 71 patients with t (4; 11) acute leukemia was made, emphasizing the following characteristics at diagnosis: female sex (62%), age under 2 years (49%), leukocyte count over 100 X 10(9)/1 (61%), splenomegaly (80%), CNS-disease (11%). Survival of over 2 years was reported in less than 15% of the patients. It remains to be seen if risk-adapted treatment can alter the course of this early B-precursor acute leukemia with hitherto very bad prognosis.  相似文献   

11.
The LEW/Ztm-ci2 rat is an autosomal recessive mutant that displays circling behavior, deafness, progressive retinopathy, locomotor hyperactivity, ataxia, and opisthotonus. We performed a genome-wide scan of a (LEW/Ztm-ci2 × BN/Ztm) F1 × LEW/Ztm-ci2 backcross population with anonymous microsatellite markers to analyze the genetics of this mutant rat. This linkage analysis demonstrated a very strong association of RNO10 SSLP markers to the phenotype with a core region in the central part of the chromosome. The knowledge of genes mapping to this part of the rat genome and their linkage to SSLP markers is still poor. We developed SSLP markers closely linked to genes, which might be responsible for the mutant phenotype by using the growing amount of rat-specific DNA sequences available at World Wide Web databases. Application of this method facilitated the search for candidate genes for the phenotype of the LEW-ci2 rat. We were able to map Myo15 and its neighboring genes, Znf179 and Aldh3a1, to the region of interest and Myo1c to a more distal location on RNO10. Further rat BAC clones were used to create a physical map of the region of interest. This map revealed the position of further genes. Among those is Kcnj12. Owing to their localization on RNO10 and their involvement in a similar pathology in human and mouse, Myo15 and Kcnj12 can be regarded as candidate genes for the deafblind phenotype of the LEW-ci2 rat.  相似文献   

12.
Culture filtrates (conditioned medium, CM) containing exudates obtained from cells of Scenedesmus subspicatus grown in batch culture were tested for their autoinduction activity. Undiluted CM completely inhibited the proliferation of cells due to depletion of nitrogen in this medium. When undiluted CM was supplemented with fresh bold basal medium (BBM) medium, enhancement of population growth in a dilution-dependent manner was observed. The most effective was 2-fold diluted CM (CM/2), whereas the growth activity of CM/20 decreased considerably. The proliferation of cells at a very low initial density (10 cells mL−1) was induced by the addition of CM/2. Biovolume, dry matter production and oxygen evolution by cells grown in 2-, 5- and 10-fold diluted CM increased markedly in both a concentration- and time-dependent manner. Conditioned medium factor (CMF) was mainly a product of rapidly dividing cells. Preliminary characterisation revealed that CMF is heat-stable, resistant to very low pH, highly hydrophilic (poorly soluble in ethanol or diethyl ether) and diffuses through a 1 kDa dialysis membrane. CM can be stored for long periods due to the time-stable activity of CMF. Depending on the enzyme applied, proteolytic digestion completely (papain, bromelain) or partially (subtilisin) abolished the activity of CM. This effect of CM was enhanced by digestion with trypsin. We suggest that CMF may be a low-molecular-weight peptide(s) or glycopeptide(s).  相似文献   

13.
A large body of research indicates that weak expressions of positive psychotic symptoms (“psychotic experiences”) can be measured in the general population, and likely represent the behavioural manifestation of distributed multifactorial (genetic and non‐genetic) risk for psychosis. Psychotic experiences are a transdiagnostic phenomenon: the majority of individuals with these experiences have a diagnosis of non‐psychotic disorder, particularly common mental disorder, in which psychotic experiences predict greater illness severity and poorer treatment response. Some of the people with common mental disorder and psychotic experiences will present to mental health services meeting criteria for “clinical high risk”. Treatment of the transdiagnostic dimension of psychosis in individuals with common mental disorder who meet “clinical high risk” criteria thus may improve outcome (which cannot be interpreted as prevention of “schizophrenia”). Subthreshold psychotic experiences are transitory in about 80% of individuals, while around 20% go on to develop persistent psychotic experiences and 7% a psychotic disorder, with an annual transition rate of 0.5‐1%. Persistence is associated, on the one hand, with environmental exposures, particularly childhood trauma, and, on the other, with network‐type dynamic interactions between psychotic experiences themselves (e.g., interactions between hallucinatory experiences and delusional ideation) and between symptom dimensions (e.g., interactions between affective symptoms and psychotic experiences, or interactions between subthreshold negative symptoms and psychotic experiences). The study of psychotic experiences is helping to elucidate the mechanisms by which environmental and genetic influences shape the transdiagnostic expression of psychosis proneness, that is mostly transitory but may first become persistent over time and eventually give rise to transition to a psychotic disorder.  相似文献   

14.
Childhood psychotic symptoms are associated with increased rates of schizophrenia, other psychiatric disorders, and suicide attempts in adulthood; thus, elucidating early risk indicators is crucial to target prevention efforts. There is considerable discordance for psychotic symptoms between monozygotic twins, indicating that child-specific non-genetic factors must be involved. Epigenetic processes may constitute one of these factors and have not yet been investigated in relation to childhood psychotic symptoms. Therefore, this study explored whether differences in DNA methylation at age 10 were associated with monozygotic twin discordance for psychotic symptoms at age 12. The Environmental Risk (E-Risk) Longitudinal Twin Study cohort of 2,232 children (1,116 twin pairs) was assessed for age-12 psychotic symptoms and 24 monozygotic twin pairs discordant for symptoms were identified for methylomic comparison. Children provided buccal samples at ages 5 and 10. DNA was bisulfite modified and DNA methylation was quantified using the Infinium HumanMethylation450 array. Differentially methylated positions (DMPs) associated with psychotic symptoms were subsequently tested in post-mortem prefrontal cortex tissue from adult schizophrenia patients and age-matched controls. Site-specific DNA methylation differences were observed at age 10 between monozygotic twins discordant for age-12 psychotic symptoms. Similar DMPs were not found at age 5. The top-ranked psychosis-associated DMP (cg23933044), located in the promoter of the C5ORF42 gene, was also hypomethylated in post-mortem prefrontal cortex brain tissue from schizophrenia patients compared to unaffected controls. These data tentatively suggest that epigenetic variation in peripheral tissue is associated with childhood psychotic symptoms and may indicate susceptibility to schizophrenia and other mental health problems.  相似文献   

15.
Jatropha curcas L. is a commercially important plant with biodiesel and medicinal potential. It is a monoecious plant with staminate and pistillate flowers in same inflorescence with number of staminate flowers being higher than pistillate ones resulting in very low fruit yield. Altering sex ratio to increase the number of female flowers would lead to better yield. Phytohormones are most important factors known to alter sex ratio in plants. The mechanism by which phytohormones alter sex ratio differs in different plant species. Among phytohormones, GA plays an important role in sex alteration. In this study, we report the effect of exogenous application of GA on sex modification in J. curcas. There was considerable increase in number of female flowers by application of GA. At lower concentrations (10 and 100 ppm), increase in number of female flowers and fruit yield was proportionate to the concentration of hormone used but at higher concentration (1,000 ppm) though there was an increase in number of female flowers, fruit yield decreased. This was due to an increased peduncle length and enhanced cell death as a consequence of endogenous release of hydrogen peroxide in response to increased GA, resulting in withering of fruits.  相似文献   

16.
A unifying theory is presented to explain the lithium exchange capacity of rocksalt‐like structures with any degree of cation ordering, and how lithium percolation properties can be used as a guideline for the development of novel high‐capacity electrode materials is demonstrated. The lithium percolation properties of the three most common lithium metal oxide phases, the layered α‐NaFeO2 structure, the spinel‐like LT‐LiCoO2 structure, and the γ‐LiFeO2 structure, are demonstrated and a strong dependence of the percolation thresholds on the cation ordering and the lithium content is observed. The poor performance of γ‐LiFeO2‐type structures is explained by their lack of percolation of good Li migration channels. The spinel‐like structure exhibits excellent percolation properties that are robust with respect to off‐stoichiometry and some amount of cation disorder. The layered structure is unique, as it possesses two different types of lithium diffusion channels, one of which is, however, strongly dependent on the lattice parameters, and therefore very sensitive to disorder. In general it is found that a critical Li‐excess concentration exists at which Li percolation occurs, although the amount of Li excess needed depends on the partial cation ordering. In fully cation‐disordered materials, macroscopic lithium diffusion is enabled by ≈10% excess lithium.  相似文献   

17.
Successful reproduction of flowering plants requires constant communication between female tissues and growing pollen tubes. Female cells secrete molecules and peptides as nutrients or guidance cues for fast and directional tube growth, which is executed by dynamic changes of intracellular activities within pollen tubes. Compared with the extensive interest in female cues and intracellular activities of pollen tubes, how female cues are sensed and interpreted intracellularly in pollen is poorly understood. We show here that COBL10, a glycosylphosphatidylinositol (GPI)‐anchored protein, is one component of this pollen tube internal machinery. Mutations in COBL10 caused gametophytic male sterility due to reduced pollen tube growth and compromised directional sensing in the female transmitting tract. Deposition of the apical pectin cap and cellulose microfibrils was disrupted in cobl10 pollen tubes. Pollen tube localization of COBL10 at the apical plasma membrane is critical for its function and relies on proper GPI processing and its C‐terminal hydrophobic residues. GPI‐anchored proteins are widespread cell sensors in mammals, especially during egg‐sperm communication. Our results that COBL10 is critical for directional growth of pollen tubes suggest that they play critical roles in cell‐cell communications in plants.  相似文献   

18.
To improve the use of the Chinese loach, Misgurnus anguillicaudatus, as a sentinel species for environmental investigations, normal ranges of plasma vitellogenin (Vtg) was studied. Male and female loaches were collected every 2 months from November 2004 to September 2005, and a specific and sensitive competitive enzyme-linked immunosorbent assay (ELISA) was used to determine plasma Vtg levels. Our data indicated that the average maximum Vtg level of female loaches (757 ± 356 μg mL−1) appeared in March, approximately 1 month before spawning. Female plasma Vtg significantly correlated with gonadosomatic index (GSI) which indicated that female plasma Vtg can be used as an indicator of the reproductive stages of the ovary. Low detectable plasma Vtg levels was detected in a number of male loaches, and the highest average plasma Vtg concentration attained to the level of μg mL−1; after exposure to estrogenic compounds by waterborne, injection or oral food, Vtg can be induced in male fish, so the presence of Vtg in male loaches might be attributed to the ingestion of estrogenic substances in food, the contamination of estrogenic compounds from the living environment, or the estrogen used by the local fish breeders to accelerate the rate of growth during artificial culture. The results indicate that Vtg levels in male and female Chinese loaches will be very helpful in field studies which use Chinese loach as a sentinel species.  相似文献   

19.
Abstract.  1. The costs and benefits of behavioural care of offspring can often be easily quantified through observations and experiments. Other forms of parental investment, on the other hand, are usually less amenable to cost–benefit analysis.
2. Here, the costs and benefits are estimated for protective egg coating by a chrysomelid beetle, Cryptocephalus hypochaeridis , where the female spends a considerable amount of time adding extra structural components to each of the eggs after laying them.
3. Adding this protective coating was very costly, both in terms of material and energy used: the mass of the extrachorion is equivalent to half the mass of the egg, and water loss and energy expenditure while coating the egg is equivalent to half what would be lost while laying a further egg.
4. Choice tests with egg predators demonstrated that these high costs are offset by benefits in terms of protection against predation: whereas uncoated eggs are readily eaten by predators, coated eggs are always rejected.  相似文献   

20.
A synopsis of the annual genus Poteranthera is presented here. Three species are recognized including the newly described Poteranthera windischii. Poteranthera is characterized by its annual life cycle, generally linear leaves that have conspicuous gland-tipped hairs on the lamina margin, 5-merous flowers with a constriction at the level of the torus, one cycle of stamens reduced to staminodia or absent altogether, three locular ovary, and reniform seeds with a foveolate testa. The flowers of the new species P. windischii are strongly heterandrous, where the usual set of stamens that bees harvest pollen from is reduced to staminodia and the stamen set that deposits pollen on the bee has large yellow ventral appendages that possibly function as pollen mimics and result in deceit pollination. This hypothesis is supported by experiments that have demonstrated innate preferences of female bees for yellow, UV absorbing colors in flowers. Species of Poteranthera are extremely rare, known from very few specimens and possibly highly endangered.  相似文献   

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