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This study explored the prevalence of social phobia (SP) in the general population of Iran, the sociodemographic characteristics of subjects with SP, and its comorbidity with the other lifetime psychiatric disorders. Our study was part of the nationwide study on the prevalence of psychiatric disorders in Iran. Overall, 25,180 Iranian subjects, age 18 years and over, from urban and rural areas of Iran were selected by a clustered random sampling method and interviewed face-to-face by 250 trained clinical psychologists using DSM-IV diagnostic criteria. Out of 12,398,235 households, 7,795 households in the form of 1,559 clusters of five households were selected. The statistical framework was based on the household lists available from the Department of Health in the provinces. The response rate was 90%. The lifetime prevalence of SP was 0.82%. The rate was 0.4% in males and 1.3% in females. The rate was higher in younger age groups and widows/widowers. It was not related to educational level and residential area. Specific phobia (66.7%), obsessive-compulsive disorder (17.4%), major depressive disorder (15%), and panic disorder (12.1%) were the most common lifetime psychiatric disorders among subjects with SP. The rate of SP in Iran is more similar to that in other Asian countries, and it is lower than that in Western countries. The rate of other psychiatric disorders among subjects with SP is more than that in the general population, and the most common psychiatric disorders were the other anxiety disorders and major depressive disorder.  相似文献   
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Background: Learning and memory are among the most important cognitive functions of the brain. Melatonin receptor type 2 (MT2R) is located in the hippocampus and participates in learning and memory processes. In the present study, we examined the role of hippocampal MT2R activation in the acquisition, consolidation, and retrieval of learning and memory in novel object recognition (NOR) and passive avoidance (PA) tasks.

Methods: IIK7 (0.03, 0.3, and 3 μg/μl/side), as a selective MT2R agonist, or vehicle was injected bilaterally into the dentate gyrus (DG) region of the hippocampus in rats five minutes before training, immediately after training, and five minutes before the retrieval-behavioral tasks, respectively. The discrimination index (DI) was measured in the NOR task, while step-through latency in acquisition (STLa), number of trials to acquisition (NOT), step-through latency in the retention trial (STLr), and time spent in the dark compartment (TDC) were determined in the PA task.

Results: The pretraining intrahippocampal injection of IIK7 at all doses significantly improved acquisition in the PA task. On the other hand, the posttraining intrahippocampal administration of IIK7 had no significant effects on consolidation. The preretrieval intrahippocampal injection of IIK7 at different doses attenuated the retrieval of memory. However, the NOR data showed that the intrahippocampal injection of IIK7 at different doses had no significant effects on the acquisition, consolidation, or retrieval in this task.

Discussion: Based on the findings, stimulation of MT2R could improve acquisition, whereas it had no effects on consolidation. It could impair retrieval in the PA task, while it had no effects on object recognition in rats.  相似文献   

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Background

Mammalian erythropoiesis can be divided into two distinct types, primitive and definitive, in which new cells are derived from the yolk sac and hematopoietic stem cells, respectively. Primitive erythropoiesis occurs within a restricted period during embryogenesis. Primitive erythrocytes remain nucleated, and their hemoglobins are different from those in definitive erythrocytes. Embryonic type hemoglobin is expressed in adult animals under genetically abnormal condition, but its later expression has not been reported in genetically normal adult animals, even under anemic conditions. We previously reported that injecting animals with nitrogen-containing bisphosphonate (NBP) decreased erythropoiesis in bone marrow (BM). Here, we induced severe anemia in a mouse model by injecting NBP injection in combination with phenylhydrazine (PHZ), and then we analyzed erythropoiesis and the levels of different types of hemoglobin.

Methods

Splenectomized mice were treated with NBP to inhibit erythropoiesis in BM, and with PHZ to induce hemolytic anemia. We analyzed hematopoietic sites and peripheral blood using morphological and molecular biological methods.

Results

Combined treatment of splenectomized mice with NBP and PHZ induced critical anemia compared to treatment with PHZ alone, and numerous nucleated erythrocytes appeared in the peripheral blood. In the BM, immature CD71-positive erythroblasts were increased, and extramedullary erythropoiesis occurred in the liver. Furthermore, embryonic type globin mRNA was detected in both the BM and the liver. In peripheral blood, spots that did not correspond to control hemoglobin were observed in 2D electrophoresis. ChIP analyses showed that KLF1 and KLF2 bind to the promoter regions of β-like globin. Wine-colored capsuled structures were unexpectedly observed in the abdominal cavity, and active erythropoiesis was also observed in these structures.

Conclusion

These results indicate that primitive erythropoiesis occurs in adult mice to rescue critical anemia because primitive erythropoiesis does not require macrophages as stroma whereas macrophages play a pivotal role in definitive erythropoiesis even outside the medulla. The cells expressing embryonic hemoglobin in this study were similar to primitive erythrocytes, indicating the possibility that yolk sac-derived primitive erythroid cells may persist into adulthood in mice.

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