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1.
Dissecting the complexity of the memory T cell response 总被引:2,自引:0,他引:2
Memory immune responses are classically attributed to the reactivation of long-lived, antigen-specific T lymphocytes that
persist in a quiescent state. Determining mechanisms for the generation of memory T cells and dissecting the functional nature
of the memory T cell pool has been encumbered by an inability to distinguish recently activated effector T cells from memory
T cells. We have established new activation and biochemical criteria that distinguish effector and memory T cells and have
applied these criteria to follow memory generation from activated cells in vivo. We found that the resultant memory T cell
pool is heterogeneous and consists of effector-like and resting memory-like subsets that differ in expression of the homing
receptor, CD62L. We discuss these findings in the context of memory T cell heterogeneity identified in human and mouse systems.
These results suggest that more than one type of previously activated T cell can mediate recall or memory immune responses
and that elucidating the fundamental phenotypic and functional features of memory T cell subsets is therefore critical to
deciphering the complex nature of the memory immune response. 相似文献
2.
Amin Sadeghi Dousari Seyed Soheil Hosseininasab Fatemeh Sadeghi Dousari Masoumeh Fuladvandi Naghmeh Satarzadeh 《World Journal of Virology》2023,12(2):91-99
The coronavirus disease 2019 (COVID-19) disease was first detected in December 2019 in Wuhan, China. This disease is currently one of the most important global health problems. The novel coronavirus COVID-19 is a respiratory illness, that has caused a deadly pandemic that is spreading rapidly around the world. It is not only a respiratory system virus that causes severe lung disease, but also a systemic disease agent that can affect all systems. People with COVID-19 disease usually have respiratory signs, however, the liver disorder is not an uncommon presentation. In addition, many studies around the world have revealed that the liver is injured to various degrees in patients with severe acute respiratory syndrome coronavirus 2 disease. This review mainly focuses on the impact of COVID-19 on Liver Injury at various ages. 相似文献
3.
Kiani Zahra Simbar Masoumeh Nazarpour Soheila Rashidi Fakari Farzaneh 《Archives of sexual behavior》2022,51(7):3223-3224
Archives of Sexual Behavior - 相似文献
4.
Mohammad Nasehi Omar Ahmadzadeh Ameneh Rezayof Mohammad-Reza Zarrindast 《Pathophysiology》2013,20(3):181-189
ObjectiveThere is some of evidence describing that cholestasis induces hypothermia. Meanwhile, there is paucity of comprehensive data on the mechanism(s) governing this phenomenon. The present study was undertaken to determine the effect of CA1 dopaminergica system on cholestasis induced hypothermia.MethodsMale NMRI mice weighing 25–30 g, were used. Bilateral cannulae were implanted in dorsal hippocampi (CA1) for drug microinjection. Animals were randomly divided into non-operated control, sham-operated and bile duct-ligated (BDL) groups. Cholestasis was induced by means of main bile duct ligation. Body temperatures were measured before, two and four days after BDL.ResultsData indicated that, two and four days post BDL, the body temperature decreases as compared to the sham-operated animals, which indicates hypothermia. Intra-CA1 injection of different doses of sulpiride (SUL; 0.25, 0.5 and 0.75 μg/mouse), SCH23390 (SCH; 0.125, 025 and 0.5 μg/mouse), SKF38393 (SKF; 0.25, 0.5 and 1 μg/mouse) and quinpirole (QUI; 0.25, 05 and 0.75 μg/mouse) exerted no effect on body temperature in non-operated and sham operated mice, by themselves. Moreover, intra-CA1 injection of SUL, QUI or SKF blocked, whereas, SCH tended to increase BDL induced hypothermia.ConclusionsThe present data revealed that the CA1 dopaminergic system is possibly involved in the BDL induced impairment of thermoregulation. 相似文献
5.
Ilnaz Sahragard Yahya Tahamtan Majid Valadan Masoumeh Hyati Farid Moazeni Zahra Shirazi 《Comparative clinical pathology》2012,21(6):1333-1336
Toxigenicity, species, and type species of Pasteurella multocida isolates cannot be differentiated by morphology or standard biochemical reactions. A more rapid method is needed for P. multocida detection from clinical cases. These findings provide rapid insights into the characteristics of P. multocida isolates and suggest that this method can identify toxigenic and specific capsular type P. multocida. A PCR assay has been developed for rapid detection of P. multocida and differentiation of capsular types A and D. In this rapid method, kmt1, capA and capD, and toxA genes were amplified and a reliable multiplex PCR method for the detection of P. multocida in sheep and goats in the south of Iran was designed. Twenty isolates were obtained, which evinced characteristic morphological and cultural properties. Ten samples were identified simultaneously through the presence of the kmt1 gene as P. multocida species, the hydD–hydC gene as type A capsule, and the toxA gene as dermonecrotic toxin by mPCR, but none of them belonged to type D. 相似文献
6.
7.
The association between obesity and migraine in a population of Iranian adults: a case-control study
Ali Miri Morteza Nasiri Sahar Zonoori Fatemeh Yarahmad Arasb Dabbagh-Moghadam Gholamreza Askari Omid Sadeghi Masoumeh Asadi 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(5):733-736
Aim
To assess the association between obesity and risk of migraine with aura and features of migraine attacks among a population of Iranian adults.Methods
In this case-control study, 102 confirmed cases of migraine with aura were matched based on age and gender with 102 healthy subjects. Data on demographic characteristics and anthropometric measurements were collected from all cases and controls by the same methods. Overweight and obesity were considered as body mass index ≥25–30?kg/m2 and?≥?30?kg/m2, respectively. Features of migraine attacks including frequency, duration and headache daily result were determined for patients based on international headache society criteria.Results
Mean age of subjects was 34.5?±?7.4 years and 77.9% of them were female. Compared with subjects with normal body mass index, those with obesity had greater odds for having migraine with aura (OR: 3.06, 95% CI: 1.11–8.43). Such finding was also seen even after adjusting for confounding variables; in a way that subjects with obesity were 2.92 times more likely for having migraine with aura compared with those with normal weight (OR: 2.92, 95% CI: 1.03-8.33). Among migraine with aura patients, we found that those with obesity had higher headache daily result compared with subjects with normal weight. However, obesity was not associated with frequency and duration of migraine attacks.Conclusions
We found that obesity was positively associated with risk of migraine with aura. In addition, subjects with obesity had higher headache daily result compared with those with normal weight. 相似文献8.
Mahsa Lotfollahi Masoumeh Gity Jing Yong Ye A. Mahlooji Far 《Journal of Medical Ultrasonics》2018,45(2):205-212
Purpose
Ultrasound imaging is an effective approach for diagnosing breast cancer, but it is highly operator-dependent. Recent advances in computer-aided diagnosis have suggested that it can assist physicians in diagnosis. Definition of the region of interest before computer analysis is still needed. Since manual outlining of the tumor contour is tedious and time-consuming for a physician, developing an automatic segmentation method is important for clinical application.Methods
The present paper represents a novel method to segment breast ultrasound images. It utilizes a combination of region-based active contour and neutrosophic theory to overcome the natural properties of ultrasound images including speckle noise and tissue-related textures. First, due to inherent speckle noise and low contrast of these images, we have utilized a non-local means filter and fuzzy logic method for denoising and image enhancement, respectively. This paper presents an improved weighted region-scalable active contour to segment breast ultrasound images using a new feature derived from neutrosophic theory.Results
This method has been applied to 36 breast ultrasound images. It generates true-positive and false-positive results, and similarity of 95%, 6%, and 90%, respectively.Conclusion
The purposed method indicates clear advantages over other conventional methods of active contour segmentation, i.e., region-scalable fitting energy and weighted region-scalable fitting energy.9.
In this paper, an efficient and straightforward synthetic approach for the preparation of a number of symmetric carboxylic anhydrides was reported using Cu2(BDC)2(DABCO) as an efficient heterogeneous catalyst via the C–H bond activation of aldehydes with excellent yields and simple work up. This C–H bond activation reaction appears simple and convenient, has a wide substrate scope and makes use of cheap, abundant, and easily available reagents. The Cu-MOF catalyst was recycled and reused four times without any loss of catalytic activity.In this paper, an efficient synthetic method for the preparation of symmetric carboxylic anhydrides was reported using Cu2(BDC)2(DABCO) as an efficient heterogeneous catalyst via the C–H bond activation of aldehydes with good yields and simple work up. 相似文献
10.
Hassan Niknejad Ghasem Yazdanpanah Masoumeh Mirmasoumi Hassan Abolghasemi Habibollah Peirovi Abolhassan Ahmadiani 《Medical hypotheses》2013
Amniotic membrane (AM), the innermost layer of the fetal membrane, is considered as a suitable candidate for cancer therapy. In order to develop the AM as a new cancer therapeutic approach, it is essential to understand the molecular mechanism of the AM anti-cancer properties. Previous studies demonstrated that anti-proliferative effects of the AM on tumor cells were associated with induction of cell cycle arrest. Moreover, it has been shown that unknown substances in the AM induce apoptosis in cancer cells and inhibit angiogenesis in tumors. In contrast to the effects of the AM, heat shock proteins (HSPs), in particular HSP90, play a crucial role in development of tumorgenesis. HSP90 inhibits apoptosis in cancer cells and enhances angiogenesis and cell cycle progression. Based on the opposite effects of the amniotic membrane ingredients and HSP90, we hypothesized here that possible mechanism of the AM anti-cancer effects is through inhibition of HSP90. 相似文献