Natural Antibody Contributes to Host Defense against an Attenuated Brucella abortus virB Mutant

Brucella abortus is an intracellular pathogen that persists within phagocytic cells of the reticuloendothelial system. To identify in vivo interactions between B. abortus and the host that lead to persistent infection, we studied the persistence of B. abortus and an isogenic virB mutant deficient in the VirB type IV secretion system (T4SS) in knockout mice. In contrast to control mice, mice lacking B cells (Igh6^−/−) were permissive for infection with the attenuated virB mutant. To determine the basis for this phenotype, we characterized immune functions of Igh6^−/− mice in the context of B. abortus infection. Igh6^−/− mice had greater numbers of extracellular bacteria in the spleen and increased early expression of proinflammatory cytokines during B. abortus infection. Further, a virB mutant, despite its wild-type level of survival, failed to elicit microgranuloma formation in the spleens of Igh6^−/− mice, suggesting a requirement for the T4SS to elicit this pathological change. Passive transfer of immunoglobulin G from naïve mice restored the ability of Igh6^−/− mice to control the persistence of the virB mutant by a complement-independent mechanism. Further, adoptive transfer of CD11b⁺ cells from C57BL/6 mice to Igh6^−/− mice restored the ability of the knockout mice to limit the replication of the virB mutant in the spleen, suggesting that the Igh6^−/− mutation affects phagocyte function and that phagocyte function can be restored by natural antibody.Human brucellosis is a febrile disease resulting from the transmission of Brucella abortus, B. suis, B. melitensis, or B. canis from its respective zoonotic reservoir in cattle, swine, goats and sheep, or dogs (47). These pathogens are endemic in many areas of the world, including Central and South America, the Mediterranean, and Central Asia, and are responsible for an estimated 500,000 new brucellosis cases each year (1). In human brucellosis, as well as in the zoonotic reservoir species, bacteria may persist for long periods of time in the reticuloendothelial system (7). This aspect of infection can be modeled in the mouse, which has been used to identify and characterize the virulence factors involved in the systemic persistence of Brucella spp. (2, 22).One essential virulence factor of the human pathogenic Brucella species is the type IV secretion system (T4SS) encoded by the virB locus on chromosome II (18, 29, 40). The T4SS of Brucella spp., similar to those of other bacterial pathogens, mediates the translocation of proteins into host cells; however, the functions of two newly identified B. abortus T4SS substrates, VceA and VceC, is not yet known (12, 25, 39, 45, 46). In cultured macrophages and dendritic cells (DC), the T4SS is essential for the intracellular replication and persistence of B. abortus (13, 36, 40). The T4SS mediates exclusion of late endosomal/lysosomal markers from the Brucella-containing vacuole and targeting of B. abortus to exit sites of the endoplasmic reticulum, where replication occurs (5, 6, 12, 41), suggesting that T4SS effectors are involved in this function. After intraperitoneal (i.p.) inoculation of mice, the T4SS is required not for the initial systemic dissemination of B. abortus but rather for persistence in the reticuloendothelial system (31, 34). In order to better understand the interactions between the host and B. abortus that lead to the persistence of wild-type (WT) strains and the eventual clearance of virB mutants, we examined the immune mechanisms required for clearance of the virB mutant. Unexpectedly, mice lacking B cells (Igh6^−/−) were permissive for the splenic persistence of the virB mutant, while the persistence of WT B. abortus was not increased. When cultured ex vivo, macrophages from Igh6^−/− mice behaved identically to macrophages from control mice in their ability to control the intracellular replication of the virB mutant while permitting the replication of WT B. abortus (34).In this study, we attempted to pinpoint the defect in Igh6^−/− mice that renders them permissive for persistent infection by the virB mutant. Our results show that nonspecific antibody can reverse the defect of these mice in controlling virB mutant replication without affecting WT B. abortus. These results suggest that the T4SS mediates the evasion of a natural antibody-dependent immune clearance function by B. abortus during persistence in vivo.     

DC‐induced CD8+ T‐cell response is inhibited by MHC class II‐dependent DX5+CD4+ Treg

CD4⁺ T cells are important for CD8⁺ T‐cell priming by providing cognate signals for DC maturation. We analyzed the capacity of CD4⁺ T cells to influence CD8⁺ T‐cell responses induced by activated DC. Surprisingly, mice depleted for CD4⁺ cells were able to generate stronger antigen‐specific CD8⁺ T‐cell responses after DC vaccination than non‐depleted mice. The same observation was made when mice were vaccinated with MHC class II^?/? DC, indicating the presence of a MHC class II‐dependent CD4⁺ T‐cell population inhibiting CD8⁺ T‐cell responses. Recently we described the expansion of DX5⁺CD4⁺ T cells, a T‐cell population displaying immune regulatory properties, upon vaccination with DC. Intriguingly, we now observe an inverse correlation between CD8⁺ T‐cell induction and expansion of DX5⁺CD4⁺ T cells as the latter cells did not expand after vaccination with MHC class II^?/? DC. In vitro, DX5⁺CD4⁺ T cells were able to limit proliferation, modulate cytokine production and induce Foxp3⁺ expression in OVA‐specific CD8⁺ T cells. Together, our data show an inhibitory role of CD4⁺ T cells on the induction of CD8⁺ T‐cell responses by activated DC and indicate the involvement of DX5⁺CD4⁺, but not CD4⁺CD25⁺, T cells in this process.     

Increased secretion of hyperimmune antibodies following lipopolysaccharide stimulation of CD40-activated human B cells in vitro

Human B cells can be cultured ex vivo for a few weeks, following stimulation of the CD40 cell surface molecule in the presence of recombinant cytokines such as interleukin-4 (IL-4). However, attempts to produce polyclonal antigen-specific human antibodies by in vitro culture of human B cells obtained from immunized donors have not been successful. It has been shown in mice that lipopolysaccharide (LPS) is a potent mitogen for B cells and plays an important role in the generation of antigen-specific antibody responses. Although it has long been believed that LPS has no direct effect on human B cells, recent data indicating that IL-4-activated human B cells are induced to express Toll-like receptor-4, the main LPS receptor, prompted us to study the effects of LPS on the proliferation and antibody secretion of human B cells. Our results showed that LPS caused a reduction in the expansion of CD40-activated human B cells, accompanied by an increase in antigen-specific antibody secretion. This result suggested that some, but not all, B cells were able to differentiate into antibody-secreting cells in response to LPS. This increased differentiation could be explained by the observation that LPS-stimulated human B cells were induced to secrete higher amounts of IL-6, a pleiotropic cytokine well-known for its B-cell differentiation activity. In vivo, the effect of LPS on cytokine secretion by B cells may not only enhance B-cell differentiation but also help to sustain a local ongoing immune response to invading Gram-negative bacteria, until all pathogens have been cleared from the organism.     

Effect of one-week treatment with vaginal estrogen preparations on serum estrogen levels in postmenopausal women

OBJECTIVE: Approximately 50% of postmenopausal women suffer from vaginal atrophy, and a large proportion of them choose intravaginal estrogen preparations administered for local action to avoid systemic exposure to estrogens and its associated risk of breast and uterine cancer. The primary objective of this study was the evaluation of the systematic bioavailability of estradiol and estrone and the pharmacokinetics of two of the most frequently used intravaginal estrogen preparations, namely Vagifem and Premarin cream. DESIGN: While immunobased assays could not previously provide accurate measurement of serum estrogen concentrations in postmenopausal women, we have used validated mass spectrometry assays to measure the pharmacokinetics of serum estradiol and estrone during the 24 hours following the seventh daily application of 25 microg estradiol (Vagifem) and 1 g (0.625 mg) conjugated estrogens (Premarin) cream in 10 postmenopausal women in each group. RESULTS: Serum estradiol was increased on average by 5.4-fold from 3 to 17 pg/mL during the 24-hour period after daily administration of 25 microg estradiol or 1 g (0.625 mg) conjugated estrogens cream. Serum estrone, conversely, increased 150% with Vagifem and 500% with Premarin cream. CONCLUSIONS: The present data using validated, accurate, and sensitive mass spectrometry assays of estrogens show that the Vagifem pill and Premarin cream, after 1 week of daily treatment, cause an approximately fivefold increase in serum estradiol in postmenopausal women, thus indicating that the effects are unlikely to be limited to the vagina and that systemic actions are expected after application of these intravaginal estrogen preparations.     

Can Quiet Standing Posture Predict Compensatory Postural Adjustment?

OBJECTIVE

The aim of this study was to analyze whether quiet standing posture is related to compensatory postural adjustment.

INTRODUCTION

The latest data in clinical practice suggests that static posture may play a significant role in musculoskeletal function, even in dynamic activities. However, no evidence exists regarding whether static posture during quiet standing is related to postural adjustment.

METHODS

Twenty healthy participants standing on a movable surface underwent unexpected, standardized backward and forward postural perturbations while kinematic data were acquired; ankle, knee, pelvis and trunk positions were then calculated. An initial and a final video frame representing quiet standing posture and the end of the postural perturbation were selected in such a way that postural adjustments had occurred between these frames. The positions of the body segments were calculated in these initial and final frames, together with the displacement of body segments during postural adjustments between the initial and final frames. The relationship between the positions of body segments in the initial and final frames and their displacements over this time period was analyzed using multiple regressions with a significance level of p ≤ 0.05.

RESULTS

We failed to identify a relationship between the position of the body segments in the initial and final frames and the associated displacement of the body segments.

DISCUSSION

The motion pattern during compensatory postural adjustment is not related to quiet standing posture or to the final posture of compensatory postural adjustment. This fact should be considered when treating balance disturbances and musculoskeletal abnormalities.

CONCLUSION

Static posture cannot predict how body segments will behave during compensatory postural adjustment.     

Risk factors for the formation of striae gravidarum in women in Jiangsu Province of China

ObjectiveWe study the risk factors that affect the formation of striae gravidarum in women in Jiangsu Province of China under current living habits.Materials and methodsThis sample is based on 400 primiparas from obstetric of the Affiliated Hospital of Jiangnan University in Wuxi from February 2017 to October 2017. Among them, there are 200 pregnant women with striae gravidarum and 200 without striae gravidarum. Striae gravidarum predictors were selected such as age, height, pre-pregnancy BMI, postpartum BMI, daily sitting time, weight gain during pregnancy, fetal weight, and diet on maternal.Results(1) The pregnant women who had striae gravidarum were generally lower in height than those who did not have striae gravidarum and had a higher BMI index than those who did not have striae gravidarum before and after childbirth. (2) In the pregnant women who have had striae gravidarum, the incidence of abdominal striae gravidarum in sedentary women is significantly lower than those in non-sedentary women, the incidence of striae gravidarum in legs is higher than those in non-sedentary women, and no significant difference in hip striae gravidarum. (3) In all pregnant women who have striae gravidarum, abdomen striae gravidarum tend to be lighter and leg striae gravidarum tends to be heavier in sedentary women, but no significant effect on the hip. (4) Regular consumption of honey, milk, trotters, freshwater fish, eggs, and tremella can reduce the incidence of striae gravidarum.ConclusionThe lifestyle and eating habits have a certain influence on the formation and severity of stretch marks.     

Increased expression of tuberin in human uterine leiomyoma

Female Eker rats harboring an insertional deletion in one copy of the tuberous sclerosis complex 2 (Tsc2) gene develop uterine leiomyoma, but the underlying mechanism of human uterine leiomyoma is not completely understood. To examine whether down-regulation of tuberin, a TSC2 gene product, is present in human uterine leiomyoma, we analyzed leiomyoma and matched myometrium tissues from 22 Chinese patients with Western blotting and real-time polymerase chain reaction analyses, and found that the expression of tuberin was significantly increased in leiomyoma tissues compared with matched myometrium tissues with inhibition of both the mammalian target of rapacmycin pathway and mitogen-activated protein kinase pathways.     

Ewing sarcoma-primitive neuroectodermal tumor of the uterus: a clinicopathologic,immunohistochemical and ultrastructural study of one case

Introduction  

Ewing sarcoma-primitive neuroectodermal tumors (ES/PNET) constitute a family of neoplasms characterized by a continuum of neuroectodermal differentiation. ES/PNET of the uterus is rare. There are 43 cases published in the English literature as far as we know. We describe an additional case.     

Sexual Rehabilitation and Penile Pain Associated with Intracavernous Alprostadil after Radical Prostatectomy

IntroductionIntracavernous alprostadil injection (IAI) is widely used for sexual rehabilitation (SR) after radical prostatectomy (RP). However, the rate of spontaneous erection recovery with IAI remains unclear, and IAI causes pain that may hinder SR.AimsTo assess SR in IAI users after RP and to evaluate the course and impact on SR of postinjection penile pain.MethodsWe prospectively studied 87 patients who underwent nerve‐sparing laparoscopic RP, reported normal preoperative erectile function, and used IAI for 12 months. Patients started with 2.5 µg alprostadil and were advised to increase the dose gradually until erection hardness allowed vaginal penetration.Main Outcome MeasuresAt 6 and 12 months, the International Index of Erectile Function (IIEF‐15) and Erection Hardness Score (EHS) were determined with and without IAI, and injection‐related penile pain was assessed using a numeric rating scale. Correlations linking penile pain, IIEF‐15, and EHS scores were evaluated.ResultsThe mean alprostadil dose was 8.1 µg after 6 months and 9.9 µg after 12 months. With/without IAI, mean IIEF‐15 scores for erectile and orgasmic function and mean EHS score were 14.6/4.6, 4.1/2.1, and 2.5/0.4, respectively, after 6 months; and 17.2/5.4, 4.9/2.6, and 2.7/0.9 after 12 months. Pain scores were 3.2 ± 2.5/10 and 2.5 ± 2.5/10 after 6 and 12 months, respectively. Pain intensity correlated with erectile function (r = ?0.23), intercourse satisfaction (r = ?0.23), and overall satisfaction (r = ?0.24) after 6 months but not after 12 months. Follow‐up was short and only patients who used IAI for 12 months were included.ConclusionsIn patients who were willing and able to use IAI, erectile function improved after 1 year but remained below preoperative levels. The adverse impact of pain on SR was significant during the first 6 months and diminished over time. These data may help to counsel IAI users with painful erections. Yiou R, Cunin P, de la Taille A, Salomon L, Binhas M, Lingombet O, Paul M, and Abbou C. Sexual rehabilitation and penile pain associated with intracavernous alprostadil after radical prostatectomy.     

CaMKIIδ在破骨细胞分化不同阶段表达规律的研究

目的:研究钙离子/钙调蛋白依赖性蛋白激酶II(Ca MKII)δ在破骨细胞分化不同阶段的表达规律,以揭示其在破骨细胞分化中的作用。方法:应用50μg/L核因子κB受体激活因子配体(RANKL)诱导小鼠RAW264.7细胞向破骨细胞分化;通过抗酒石酸酸性磷酸酶(TRAP)染色及骨磨片吸收陷窝检测评价破骨细胞生成情况;同时于诱导第0、1、3、5天末通过免疫荧光细胞化学、RT-q PCR和Western blot法检测Ca MKIIδ的mRNA及蛋白表达水平。结果:TRAP染色及骨吸收陷窝检测显示于诱导第5天有多核破骨细胞生成。第0、1、3、5天Ca MKIIδ的mRNA表达水平分别为1.028±0.041、2.478±0.087、10.524±1.284和42.914±2.667,蛋白相对水平分别为0.762、0.963、1.802和3.136,免疫荧光细胞化学检测显示Ca MKIIδ的荧光6强度呈时间依赖性递增。结论:Ca MKIIδ的表达随破骨细胞分化逐步增高,提示Ca MKIIδ在破骨细胞分化中可能起着关键调控作用。