Topographic differences in adult neurogenesis in the mouse hippocampus: A stereology‐based study using endogenous markers

The hippocampus plays a critical role in various cognitive and affective functions. Increasing evidence shows that these functions are topographically distributed along the dorsoventral (septotemporal) and transverse axes of the hippocampus. For instance, dorsal hippocampus is involved in spatial memory and learning whereas ventral hippocampus is related to emotion. Here, we examined the topographic differences (dorsal vs. ventral; suprapyramidal vs. infrapyramidal) in adult neurogenesis in the mouse hippocampus using endogenous markers. The optical disector was applied to estimate the numerical densities (NDs) of labeled cells in the granule cell layer. The NDs of radial glia‐like progenitors labeled by brain lipid binding protein were significantly lower in the infrapyramidal blade of the ventral DG than in other subdivisions. The NDs of doublecortin‐expressing cells presumed neural progenitors and immature granule cells were significantly higher in the suprapyramidal blade of the dorsal DG than in the other subdivisions. The NDs of calretinin‐expressing cells presumed young granule cells at the postmitotic stage were significantly higher in the suprapyramidal blade than in the infrapyramidal blade in the dorsal DG. No significant regional differences were detected in the NDs of dividing cells identified by proliferating cell nuclear antigen. Taken together, these findings suggest that a larger pool of immature granule cells in dorsal hippocampus might be responsible for spatial learning and memory, whereas a smaller pool of radial glia‐like progenitors in ventral hippocampus might be associated with the susceptibility to affective disorders. Cell number estimation using a 300‐μm‐thick hypothetical slice indicates that regional differences in immature cells might contribute to the formation of topographic gradients in mature granule cells in the adult hippocampus. Our data also emphasizes the importance of considering such differences when evaluating changes in adult neurogenesis in pathological conditions and following experimental procedures. © 2010 Wiley‐Liss, Inc.     

Influence of endogenous ciliary neurotrophic factor on neural differentiation of adult rat hippocampal progenitors

Ciliary neurotrophic factor is the only known neurotrophic factor that can promote differentiation of hippocampal neural progenitor cells to glial cells and neurons in adult rats. This process is similar to spontaneous differentiation. Therefore, ciliary neurotrophic factor may be involved in spontaneous differentiation of neural stem cells. To verify this hypothesis, the present study isolated neural progenitor cells from adult male rats and cultured them in vitro. Results showed that when neural progenitor cells were cultured in the absence of mitogen fibroblast growth factor-2 or epidermal growth factor, they underwent spontaneous differentiation into neurons and glial cells. Western blot and immunocytochemical staining showed that exogenous ciliary neurotrophic factor strongly induced adult hippocampal progenitor cells to differentiate into neurons and glial cells. Moreover, passage 4 adult hippocampal progenitor cells expressed high levels of endogenous ciliary neurotrophic factor, and a neutralizing antibody against ciliary neurotrophic factor prevented the spontaneous neuronal and glial differentiation of adult hippocampal progenitor cells. These results suggest that the spontaneous differentiation of adult hippocampal progenitor cells is mediated partially by endogenous ciliary neurotrophic factor.     

宫腹腔镜联合手术治疗内生型剖宫产瘢痕妊娠的临床效果

目的 探讨宫腹腔镜联合手术治疗内生型剖宫产瘢痕妊娠(CSP)的临床效果.方法 选取2019年2月至2021年1月我院收治的70例内生型CSP患者作为研究对象,根据手术方式不同将其分为乙组与甲组,各35例.乙组给予腹腔镜手术治疗,甲组在乙组基础上给予宫腔镜手术治疗.比较两组的手术相关情况、瘢痕形态、子宫内膜厚度、血清人绒...     

Role of Cyclooxygenases in the Stimulatory Effect of Carcinogen 1,2-Dimethylhydrazine on Stem Cell Survival in the Intestinal Epithelium and Bone Marrow

In vivo experimental studies showed that 1,2-dimethylhydrazine and product of its metabolism in the body azoximethane improve postradiation survival of two types of stem cells in the adult organism: hemopoietic stem cells and intestinal epithelial stem cells. This effect similar to the well-known radioprotective effect of E. coli lipopolysaccharide was observed, when the carcinogen was administered 1 day before γ-irradiation. Treatment with 1,2-dimethylhydrazine prolonged the mean life-span of mice irradiated in supralethal doses inducing death of the majority of intestinal epithelial stem cells. Nonspecific cyclooxygenase inhibitor indometacin weakened this radioprotective effect of 1,2-dimethylhydrazine. We also found that carcinogen 1,2-dimethylhydrazine improved survival of hemopoietic stem cells. However, in contrast to intestinal epithelial stem cells, indometacin did not inhibit the radioprotective effect of the carcinogen. The radioprotective effect of 1,2-dimethylhydrazine and lipopolysaccharide on stem cells in the presence of indometacin was a sum of individual effects of these preparations and indometacin. Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 4, pp. 226–229, November, 2008     

Enteral feeding tube guidewire—another factor in the retrograde contamination of enteral feeding systems?

Background: In vitro enteral feeding systems were used to investigate the effect that withdrawal of the guidewire from the feeding tube has on bacteria ascending from a patients’ stomach or intestine via the feeding tube to the giving set and nutrient container of the feeding system. Methods: Enteral feeding systems were assembled with the feeding tube running into nutrient broth contaminated with Klebsiella aerogenes. The enteral feeding tubes were held in different orientations (horizontal and vertical) to examine the effect in both prostrate and ambulant patients. The guidewire was removed either prior to or after the enteral feeding tube had been inserted into the K. aerogenes broth. Feed was then run through the systems for 24 h, with feed samples being collected from the distal (patient) end of the giving set at 0 and 24 h. Results: After 24 h, 10^3–108 c.f.u. (colony forming units) K. aerogenes/ml were detected in feed samples taken from the distal end of the giving set in systems where the guidewire had been removed after the enteral feeding tube had been inserted into the contaminated broth (both orientations), but K. aerogenes was not detected in samples from systems in which the guidewire had been removed before the end of the tube was inserted into the broth (both orientations). However, when the latter feed samples were enriched (i.e. incubated at 37 °C for a further 24 h to detect if very low levels of bacteria were present in the original sample), 40% of samples from systems with horizontally orientated tubes, and 20% from systems with vertically orientated tubes were positive for the test organism. K. aerogenes was not detected in any samples of feed taken from the nutrient container or just below the drip chamber. Conclusion: The results demonstrate: (i) that bacteria ascend the feeding tube over a 24-h period (retrograde contamination) and (ii) removal of the guidewire can contribute to the colonization of the lumen of the feeding tube and distal end of the giving set with bacteria from a patients’ own flora.     

Signal splitting as the basis for involvement of natural cytotoxicity system in endogenous biological retranslation

The ability of natural killers to split biological signal (dissociation of cytotoxic and interferon-producing activities) is the main precondition of the involvement of the natural cytotoxicity system in endogenous biological retranslation. Dissociation of the primary functions of natural cytotoxicity effectors is provided by enhanced interferon production against the background of decreased cytotoxicity of natural killers, or by enhanced natural cytotoxicity against the background of almost complete inhibition of interferon production. Dissociation of the primary functions of natural killers is a physiological phenomenon; it is induced and maintained by factors, which are not directly connected with induction or suppression of the immune response. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 12, pp. 604–612, December, 1999     

小儿体外循环术中抑肽酶对IL-10的影响及临床意义

目的 :探讨小儿体外循环术中抑肽酶对IL 10的影响及量效关系。方法 :按入选标准筛选病例并分成三组 :对照组 (A组 ,n =12 )、小剂量抑肽酶组 (B组 ,n =12 )、大剂量抑肽酶组 (C组 ,n =2 0 )。用酶联免疫吸附试验法测定各患儿在术前、体外循环 (ECC) 3 0min、ECC结束后 2h、2 4h、7d五个时间点血清IL 10的浓度。结果 :各组ECC3 0min ,ECC结束后 2h血清IL 10浓度与术前相比显著增高 (P <0 .0 1) ,且B、C组与A组相比 ,C组与B组相比 ,IL 10水平增高更为明显 ,各组间差异有显著性 (P <0 .0 1) ;C组术后住院日明显缩短 (P <0 .0 1)。结论 :抑肽酶能促进内源性IL 10的释放 ,从而抑制小儿ECC引起的全身炎性反应 ,且药效与抑肽酶剂量呈正相关     

猪内源性反转录病毒在中国实验小型猪中的存在与表达

目的对中国实验小型猪中内源性反转录病毒的存在与mRNA的表达进行检测,摸清中国实验小型猪中内源性反转录病毒的携带情况.方法根据已发表的PERV的序列设计并合成了三对引物,分别用于检测PERV核心蛋白基因(gag)、多聚酶基因(pol)及囊膜基因(env)的存在与表达;同时,根据目前通用的env基因分型方法合成了三对用于分型检测的引物env-A、env-B、env-C.应用PCR、RT-PCR扩增的方法,对来自于中国实验小型猪外周血淋巴细胞的DNA和RNA样品进行了检测.结果在6个被检DNA样品中均检出了PERV特异性DNA的存在;同样,在被检RNA样品中均有PERV特异性RNA的表达,且所表达的PERV均为A型和B型,在所有样品中均未检出C型PERV的表达.结论初步表明中国实验小型猪中存在内源性反转录病毒序列,且能以mRNA的形式表达,这一结果为我国特有小型猪的开发、利用及其病毒安全性评价奠定了基础.     

Involvement of natural killer cells in endogenous biological retranslation

Analysis of functional properties of natural killer cells displayed in reactions of natural cytotoxicity and noncytotoxic regulatory intercellular interactions suggests that this population of lymphocytes is involved in endogenous biological retranslation. In the immune system, retranslation is the production of regulatory immunoactive cytokines by a cell, cellular complex, or functional complex. The substances produced are identical to those affecting these structures. Various forms of endogenous biological retranslation in humans and higher animals, as well as its phylogenetic and ontogenetic manifestations (on the basis of noncytotoxic regulatory interactions of natural killer cells with cells of lymphoid or nonlymphoid nature) during evolution of the complex of immunobiological surveillance are considered. The axiomatic basis of retranslation realized through the system of natural cytotoxicity was established. Prospects for application of the methodology of endogenous biological retranslation to experimental and clinical studies of functioning of natural killer cells are considered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 124–135, August, 1998     

Systemic lupus erythematosus and human endogenous retroviruses

 Human endogenous retroviruses (HERV) are known to be widely present in the human genome. Several investigations have suggested a possible etiological role of HERV in certain human disorders, including systemic lupus erythematosus (SLE). Here we review and discuss the possible role of HERV, especially HERV clone 4-1, in the onset of SLE, based on recent findings including our own data. Received: September 25, 2002 / Accepted: December 10, 2002