Molecular mechanisms of lymphocyte extravasation. III. The loss of lymphocyte extravasation potential induced by pertussis toxin is not mediated via the activation of protein kinase C

The present study evaluated whether protein kinase C (PKC) activation was involved in the lymphocytosis promoting properties of pertussis toxin (Ptx). The exposure of mouse lymphocytes to phorbol esters (as a means to selectively activate PKC) caused a depression in their subsequent capacity to localize into lymph nodes and Peyer's patches in vivo. This pattern of inhibition was quite similar to that observed with lymphocytes treated with Ptx. The mechanisms responsible for the observed decreases in localization to lymphoid organs caused by these two agents, however, appeared to be distinct. Exposure of lymphocytes to PMA was followed by a time and dosage-dependent decrease in the surface density of MEL-14 defined homing receptors. Ptx-treated lymphocytes retained normal density of this homing receptor. Consequently, PMA-treated lymphocytes lost their capacity to bind to high-endothelial venules in in vitro lymph node binding assays while Ptx-treated cells retained normal high-endothelial venule binding potential. We conclude from this study that: 1) the activation of PKC in lymphocytes by PMA can alter their recirculation properties via mechanisms that diminish their expression of surface receptors which support extravasation into lymph node and mucosal lymphoid tissues, and 2) even though Ptx has been reported to elevate the rate of inositol phosphate turnover in lymphocytes, the loss of extravasation potential of Ptx-treated lymphocytes is not mediated via the modification of surface homing receptors as observed in cells exposed to the known PKC activator, PMA.

Identification of estrogenically synthesized LRP16 as an ERα coactivator and its role in ERα-positive breast cancer

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Background: Aberrant ERα activity is linked to genesis and malignant progression of breast cancer through direct target gene activation or repression. A complex network of coregulatory proteins is largely believed to determine the transcriptional activity of ERα. LRP16 was identified previously to be an estrogen (E2) responsive gene, but its function involving in conferring estrogen signalling pathway is not clear. Methods: Endogenous LRP16 expression in MCF-7 cells was stably suppressed by retrovirus-mediated small interference RNA (siRNA). The effects of LRP16 expression on E2-stimulated growth and invasive ability of MCF-7 cells were determined in vitro and in vivo assays. The effects of LRP16 expression on ERα transactivation were determined by luciferase assays. The interaction of LRP16 and ERα was examined by GST pull-down and coimmunopricipitation (CoIP) assays. Northern blot and Western blot were used to detect the mRNA and protein levels of ER target genes in LRP16-inhibited MCF-7 cells. The LRP16 expression levels in primary breast cancer were detected by Northern blot. Results: Fristly, LRP16 expression was characterized to be dependent on estrogen activities. Then, LRP16 was identified to be an estrogen-independent ERα cofactor in ER-positive breast cancer cells and demonstrate that LRP16 is an essential coactivator to ERα-mediated transactivation in an estrogen-dependent manner. Suppression of LRP16 expression in ER-positive breast cancer cells specifically inhibits the transcription of ER upregulated genes, results in the increase of E-cadherin expression through ER mediation. In vitro and in vivo data demonstrate that suppression of LRP16 inhibits the ability of estrogen-stimulated proliferation and invasiveness of ER-positive breast cancer cells. The pathological and clinical characteristics of human breast cancer includining ER/PR-positiveness, tumor diameter and the involvement of axillary lymphoid nodes were tightly linked with the LRP16 gene expression level. Conclusions: These results establish a mechanistic link between estrogen receptor status, its coactivator LRP16, and progression of ER-positive breast cancers, and may provide a novel antiestrogenic target for the therapy of ER positive breast cancer.

No significant financial relationships to disclose.

[Association between elective cesarean section and infants' developmental behaviors: a cohort study]

Objective: To investigate the effect of elective cesarean section (ECS) on infants' developmental behaviors. Methods: A total of 3 474 pregnant women living in Ma'anshan more than 6 months and accepting obstetric examination in Ma'anshan Maternal and Child Care Center were recruited from May 2013 to September 2014. Excluding participants with pregnancy termination (162), twin pregnancy (39), assisted delivery (14), emergency cesarean section (76) and unclear delivery mode (141), 3 042 pair of mother and infant entered the final analysis. Information of maternal basic demographic characteristics, pregnancy histories, pregnancy life style and pregnancy-related diseases were collected by using self-complied Maternal and Child Health Questionnaire. Information of infants' general condition and delivery modes were acquired from obstetric record. The Ages and Stages Questionnaires-third edition was used to assess infants' communication, gross motor, fine motor, problem solving and person-social function, which was completed at age of 6 months old and 18 months old, respectively. And multi-factor non-conditional logistic regression model was used to analyze the association between ECS and infants' developmental behaviors. Results: The prevalence of ECS was 47.5% (1 443/3 042), among which ECS without medical indication and ECS with medical indication were 27.2% (826/3 042) and 20.3% (617/3 042), respectively. After maternal demographic characteristics, pregnant exposure and infants' basic information adjusted, compared to women with vaginal delivery, both ECS with medical indication and without medical indication increased the risk of a delay in gross motor on infants at 6 months old (RR (95%CI: 1.72 (1.08-2.77) and 1.87 (1.11-3.15), respectively.) ECS without indication decreased the risk of a delay in fine motor on infants at 6 months old (RR (95%CI):0.48 (0.28-0.82)), both ECS without medical indication and with medical indication had no statistically significant effect on 18 months infants' communication, gross motor, fine motor, problem solving and person-social function, the RR (95%CI) for ECS without medical indication were 0.86 (0.43-1.74), 1.55 (0.86-2.78), 0.74 (0.49-1.15), 1.10 (0.68-1.78) and 1.17 (0.66-2.08), respectively; and the RR (95%CI) for ECS with medical indication were 0.33 (0.12-1.02), 1.10 (0.55-2.21), 0.79 (0.48-1.29), 0.58 (0.29-1.13) and 1.48 (0.78-2.81), respectively. Conclusion: ECS affected motor development in infants at the age of 6 months old, and no influence was found in infants at the age of 18 months old.

[Determinants of pregnancy rate in the donor oocyte model: a multivariate analysis of frozen-thawed embryo transfers]

Objective: To determine independent factors of pregnancy in the recipient after frozen-thawed embryo transfer (FTET). Methods: We performed a retrospective study of 431 patients who had undergone embryo transfer after oocyte donation (OD), in vitro fertilization and embryo cryopreservation between April 2009 and December 2018 at our Reproductive Center. Comparison of general data between clinical pregnant group and non-pregnant group; Logistic regression were used to identify independent factors of pregnancy. The ability of independent factors of pregnancy was assessed by receiver operating characteristics (ROC). Results: ①Pregnancy rates were significantly higher in women with more embryos, more high-quality embryos, more transferred embryos and higher basalfollicular stimulation hormone(FSH) (P<0.05). Pregnancy rate of premature ovarian insufficiency (POI) (75.00%) was higher than advanced age (55.83%,P=0.005) and chromosome abnormality (56.86%,P=0.021). ②Using logistic regression analysis, the POI (OR=2.065, 95%CI=1.026-4.156), basal FSH(OR=1.499, 95%CI=1.072-1.959), high-quality embryos (OR=1.449, 95%CI=1.072-1.959) and transferred embryos (OR=2.583, 95%CI=1.519-4.391)were independent predictors of pregnancy (P<0.05). ③The ROC curves revealed the cut-off points of basal FSH was 19.28U/L for pregnancy, the areas under the curve of basal FSH was 0.627, 95%CI=0.572-0.680. According basal FSH and age, all patients were further divided into four groups, pregnancy rates were significantly higher in ≤40 years and FSH>19U/L group (P<0.05). We contain pregnancy rates and multiple pregnancy rates of two transferred embryos were higher than one (P<0.01). Conclusions: This study supports that pregnancy rates of POI was higher than other infertility diagnosis needed OD. Pregnancy rates of two transferred embryos were higher than one, but multiple pregnancy rates was also higher than one.

A transdiagnostic and translational framework for delineating the neuronal mechanisms of compulsive exercise in anorexia nervosa

OBJECTIVE

The development of novel treatments for anorexia nervosa (AN) requires a detailed understanding of the biological underpinnings of specific, commonly occurring symptoms, including compulsive exercise. There is considerable bio-behavioral overlap between AN and obsessive-compulsive disorder (OCD), therefore it is plausible that similar mechanisms underlie compulsive behavior in both populations. While the association between these conditions is widely acknowledged, defining the shared mechanisms for compulsive behavior in AN and OCD requires a novel approach.

METHODS

We present an argument that a better understanding of the neurobiological mechanisms that underpin compulsive exercise in AN can be achieved in two critical ways. First, by applying a framework of the neuronal control of OCD to exercise behavior in AN, and second, by taking better advantage of the activity-based anorexia (ABA) rodent model to directly test this framework in the context of feeding pathology.

RESULTS

A cross-disciplinary approach that spans preclinical, neuroimaging, and clinical research as well as compulsive neurocircuitry and behavior can advance our understanding of when, why, and how compulsive exercise develops in the context of AN and provide targets for novel treatment strategies.

DISCUSSION

In this article, we (i) link the expression of compulsive behavior in AN and OCD via a transition between goal-directed and habitual behavior, (ii) present disrupted cortico-striatal circuitry as a key substrate for the development of compulsive behavior in both conditions, and (iii) highlight the utility of the ABA rodent model to better understand the mechanisms of compulsive behavior relevant to AN.

PUBLIC SIGNIFICANCE

Individuals with AN who exercise compulsively are at risk of worse health outcomes and have poorer responses to standard treatments. However, when, why, and how compulsive exercise develops in AN remains inadequately understood. Identifying whether the neural circuitry underlying compulsive behavior in OCD also controls hyperactivity in the activity-based anorexia model will aid in the development of novel eating disorder treatment strategies for this high-risk population.

[Preoperative diagnostic value of 99mTc- MIBI SPECT/CT imaging combined with semiquantitative analysis in hyperparathyroidism and factors affecting its efficacy]

OBJECTIVE

To evaluate the diagnostic efficacy of technetium-99m methoxyisobutylisonitrile single photon emission/ computed tomography (^99mTc- MIBI SPECT/CT), ^99mTc- MIBI double- phase scintigraphy (DPS) DPS and ultrasound (US) in preoperative localization of hyperparathyroidism (HPT) and explore the factors affecting the diagnostic efficacy of ^99mTc-MIBI SPECT/CT.

METHODS

We retrospectively analyzed the data of 104 patients with HPT undergoing surgical resection between January, 2015 and July, 2019. Preoperative ^99mTc-MIBI imaging was performed in all the patients, and 82 patients also received US examination preoperatively. Semi-quantitative analysis was used to draw the region of interest and calculate the lesion/ ipsilateral deltoid muscle (T/NT) uptake ratio. The sensitivity and detection performance of ^99mTc-MIBI SPECT/CT, DPS and US in the diagnosis of HPT patients were compared, and the correlations of the T/NT ratios of parathyroid adenoma (PA) and parathyroid hyperplasia (PH) with the expression levels of COX-2 and Bcl-2 were analyzed.

RESULTS

The diagnostic sensitivity of ^99mTc- MIBI SPECT/CT, DPS and US for HPT was 95.19% (99/104), 91.3% (95/104) and 81.71% (67/82), respectively, demonstrating a significantly higher diagnostic sensitivity of ^99mTc-MIBI SPECT/CT than US (χ²=9.59, P=0.008). For PH lesions, ^99mTc-MIBI SPECT/CT had the highest diagnostic sensitivity, followed by DPS and then by US (P < 0.05), but their sensitivity did not differ significantly for PA (P>0.05). The T/NT ratio in fatty hyperplastic glands was significantly lower than that in fat-free hyperplastic glands (P=0.009). In PA, Bcl-2 expression was significantly lower in false negative lesions than in true positive lesions (P=0.046), but Cox-2 expression did not show such a difference (P>0.05). In PH lesions, the expressions of Bcl-2 and Cox- 2 did not differ significantly between false negative than true positive lesions (P>0.05).

CONCLUSIONS

^99mTc-MIBI SPECT/CT has a high sensitivity for HPT localization, and the T/NT ratio is positively correlated with the lesion volume. An increased expression of Bcl-2 in PA lesions and a decreased cell fat content in PH lesions can facilitate the detection of HPT glands by ^99mTc-MIBI SPECT/CT.

Fine Particulate Matter Exposure, Genetic Susceptibility, and the Risk of Incident Stroke: A Prospective Cohort Study

BACKGROUND

Both genetic factors and environmental air pollution contribute to the risk of stroke. However, it is unknown whether the association between air pollution and stroke risk is influenced by the genetic susceptibilities of stroke and its risk factors.

METHODS

This prospective cohort study included 40 827 Chinese adults without stroke history. Satellite-based monthly fine particulate matter (PM2.5) estimation at 1-km resolution was used for exposure assessment. Based on 534 identified genetic variants from genome-wide association studies in East Asians, we constructed 6 polygenic risk scores for stroke and its risk factors, including atrial fibrillation, blood pressure, type 2 diabetes, body mass index, and triglyceride. The Cox proportional hazards model was applied to evaluate the hazard ratios and 95% CIs for the associations of PM2.5 and polygenic risk score with incident stroke and the potential effect modifications.

RESULTS

Over a median follow-up of 12.06 years, 3147 incident stroke cases were documented. Compared with the lowest quartile of PM2.5 exposure, the hazard ratio (95% CI) for stroke in the highest quartile group was 2.72 (2.42-3.06). Among individuals at high genetic risk, the relative risk of stroke was 57% (1.57; 1.40-1.76) higher than those at low genetic risk. Although no statistically significant interaction was found, participants with both the highest PM2.5 and high genetic risk showed the highest risk of stroke, with ≈4× that of the lowest PM2.5 and low genetic risk group (hazard ratio, 3.55 [95% CI, 2.84-4.44]). Similar upward gradients were observed in the risk of stroke when assessing the joint effects of PM2.5 and genetic risks of blood pressure, type 2 diabetes, body mass index, atrial fibrillation, and triglyceride.

CONCLUSIONS

Long-term exposure to PM2.5 was associated with a higher risk of incident stroke across different genetic susceptibilities. Our findings highlighted the great importance of comprehensive assessment of air pollution and genetic risk in the prevention of stroke.

Air Pollution and Cognitive Impairment Among the Chinese Elderly Population: An Analysis of the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

Cognitive impairment and dementia have long been recognized as growing public health threats. Studies have found that air pollution is a potential risk factor for dementia, but the literature remains inconclusive. This study aimed to evaluate the association between three major air pollutants (i.e., PM2.5, O3, and NO2) and cognitive impairment among the Chinese elderly population. Study participants were selected from the Chinese Longitudinal Health Longevity Survey (CLHLS) after 2005. We define cognitive impairment as a Chinese Mini-Mental-State Exam (CMMSE) score <24. The associations of air pollution with cognitive impairment and CMMSE score were evaluated with a logistic regression model and a linear mixed-effect model with random intercepts, respectively. A total of 3,887 participants were enrolled in this study. Of the 2,882 participants who completed at least one follow-up visit, 931 eventually developed cognitive impairment. In single-pollutant models, we found that yearly average PM2.5 and NO2 as well as warm season O3, were positively associated with cognitive impairment. NO2 remained positively associated with cognitive impairment in the multi-pollutant model. The linear mixed-effect models revealed that warm season O3 and yearly average NO2 were significantly associated with decreased CMMSE scores. Our research has established a positive association between cognitive impairment and air pollution in China. These findings underscore the imperative for the next iteration of China's Air Pollution Prevention and Control Action Plan to broaden its focus to encompass gaseous air pollutants since mitigating single air pollutant is insufficient to protect the aging population.

[A systematic study on comprehensive utilization of fibers of radix Ophiopogonis]

The components, toxicology, bioactivity and application of fibers of Radix Ophiopogonis (RO) were studied. The components of its fibers and roots are similar. In a clinical study with 100 aged patients, the aging syndromes were markedly improved. No side-effect was found.

[Effect of phosphorylation by protein kinase C on the DNA binding activity of high mobility group protein I]

High mobility group protein I (HMG-I) is a nonhistone chromosomal protein. The present study aims to examine phosphorylation of HMG-I by protein kinase C (PKC) and its effect on HMG-I's DNA binding activity. HMG-I, extracted and purified from rat brain was phosphorylated in vitro equally well by PKC alpha, beta, gamma and delta. Phosphoamino acid analysis indicated that both serine and threonine residues were phosphorylated. The nonphosphorylated HMG-I was shown to bind specifically to the fragment of DNA containing bp -708 to -458 of RC3 genomic DNA, which is abundant in A-T sequences. In contrast, phosphorylation of HMG-I by PKC resulted in an attenuation of binding to the DNA fragment. It is suggested that phosphorylation of HMG-I by PKC may regulate DNA binding activity of HMG-I, thereby possibly altering its biological functions.

[Experimental studies about effect of dexamethasone on diaphragm of normal rats]

The influence of dexamethasone on diaphragm function, its oxidative capacity, fiber cross-sectional areas, the content of glycogen and ultrastructural changes were determined in Wistar rats by receiving dexamethasone (2 mg/kg) muscle injection for two weeks. We noted dexamethasone treatment leads to significant atrophy of the mass of diaphragm, reduction of fiber cross-sectional areas (CSA) of type II a, II b fibers. Under high frequency (100 Hz) stimulation, the tention of the diaphragm muscle strips was decreased and diaphragm fatigue resistance (1/2 RT) was significantly improved. Histochemically, ATPase activity in type I and type II b fibers of the diaphragm was significantly reduced and a significant reduction of succinate dehydrogenase activity in the diaphragm was also observed, but increased glycogen was seen in the diaphragm. Ultrastructural changes including mitochondrial hyperplasia, swelling, myofibillae focus destructure were evident. It is concluded that steroid-induced myopathy may also involve the diaphragm.

[Progress on evaluation criterion of wound healing]

OBJECTIVE

To set up some objective and accurate criteria to evaluate wound healing.

METHODS

Documents about wound healing were reviewed and summarized in detail.

RESULTS

Wound healing rate, wound healing time, histopathology analysis, quantity assay of macrophage, determination of hydroxyproline, proliferation of cell, assay of DNA contents and circle of cells, level of transforming growth factor-alpha, levels of interleukin-1, interleukin-6 and tumor necrosis factor, assay of keratinocyte collagenase-1, level of fibroblast growth factor receptor-1, level of monocyte chemoattractant protein-1 and level of keratinocyte plasminogen activator inhabitor type 2 were selected as the evaluation criteria of wound healing.

CONCLUSION

Wound healing rate, wound healing time and histopathology analysis are direct and efficient criteria of wound healing.

[Sequential non-invasive following short-term invasive mechanical ventilation in COPD induced hypercapnic respiratory failure]

OBJECTIVE

To estimate the feasibility and the efficacy of early extubation and sequential non-invasive mechanical ventilation(MV) in COPD with exacerbated hypercapnic respiratory failure.

METHODS

22 intubated COPD cases with severe hypercapnic respiratory failure due to pulmonary infection (pneumonia or purulent bronchitis) were involved in the study. At the time pulmonary infection had been significantly controlled (resolution of fever and decrease in purulent sputum, radiographic infiltrations, and leukocytosis. We call the time as "Pulmonary Infection Control Window", PIC window) after the antibiotic and the comprehensive therapy, the early extubation was conducted and followed by non-invasive MV via facial mask immediately in 11 cases (study group). Other 11 COPD cases with similar clinical characteristics who continuously received invasive MV after PIC window were used as control group.

RESULTS

The groups had similar clinical characteristics and gas exchange, initially and at the time of PIC window. For study group and control group, the duration of invasive MV was (7.1 +/- 2.9) vs (23.0 +/- 14.0) days, P < 0.01; the total duration of ventilatory support was (13 +/- 7) vs (23 +/- 14) days, P < 0.05; the incidence of VAP were 0/11 vs 6/11, P < 0.01; the duration of ICU stay was (13 +/- 7) vs (26 +/- 14) days, P < 0.05, respectively.

CONCLUSIONS

In COPD patients requiring intubation and MV for pulmonary infection and hypercapnic respiratory failure, early extubation followed by non-invasive MV initiated at the point of PIC window may significantly decrease the invasive and total durations of ventilatory support, the risk of VAP, and the duration of ICU stay.

[Assay of sensitivity of Plasmodium falciparum to chloroquine, amodiaquine, piperaquine, mefloquine and quinine in Yunnan province]

AIM

To determine the sensitivity of P. falciparum to chloroquine, amodiaquine, piperaquine, mefloquine and quinine in Yunnan Province of China in 1992-1995.

METHODS

Rieckmann's in vitro microtechnigue was used. The sensitivity of P. falciparum was tested to the above-mentioned antimalarials.

RESULTS

The resistance rates of isolates of P. falciparum from the south, southeast and the west part of Yunnan to chloroquine and amodiaquine were 96.7% (29/30), 78.9% (30/38), 95.7% (22/23) and 100% (30/30), 85.3% (29/34), 8/9, respectively, with their corresponding ID50 of 125 nmol/L, 136 nmol/L and 176 nmol/L, and 52 nmol/L, 64 nmol/L and 72 nmol/L, respectively. All the isolates were sensitive to quinine and their ID50 were 480 nmol/L, 352 nmol/L, 608 nmol/L, respectively. The resistance rates of P. falciparum from the south part and southeast part of Yunnan to piperaquine were 96.4% (27/29), 72.9 (27/37), respectively, their ID50 were 320 nmol/L and 228 nmol/L; all the cases were sensitive to mefloqine, their ID50 were 68 nmol/L and 88 nmol/L.

CONCLUSION

P. falciparum generally produces resistance to chloroquine, amodiaquine and piperaquine in Yunnan Province; the degree of resistance to chloroquine of P. falciparum from the west part of Yunnan were higher than the P. falciparum from the southeast part of Yunnan; all the isolates were sensitive to mefloquine and quinine in this region.

[Studies on the ribosomal RNA gene(rDNA) of a microsporidium isolated from Pieris rapae L]

Nuclotide sequence (1205 bp) of small subunit ribosomal RNA (SSUrDNA) of a microsporidium isolated from Pieris rapae L. (abbr:MPr) was specifically amplified by polymerase chain reaction (PCR). Another fragment of 657 bp downstream of MPr SSUrDNA 3'end was amplified with two other primers. Within this 657 bp fragment, the putative 3'terminus of MPr SSUrDNA and the extreme 5' of large subunit ribosomal RNA gene. (LSUrDNA) were identified, which situated at base 145, 146-186 and 187, respectively. Then the full sequence of MPr ssurDNA is 1245 bp. Its GC content was also nearly 34%. The ITS region (internal transcribed spacer), positioned between the ssu and LSUrRNA genes, was found to be 41 bp in length. The LSUrDNA 580r region of MPr is 470 bp, longer than 437 bp of Nosema apis, 447 bp of Nosema algerae. The secondary structure of MPr SSUrRNA was constructed. These analyses of MPr rRNA gene contributed to the somewhat limited microsporidian taxonomic classification based on morphology.