[Pathogenic agents causing acute respiratory tract infections in pediatric patients in Spring, 2023, in Beijing].

Objective: To explore the pathogenic agents of acute respiratory infection (ARI) in children in Beijing. Methods: In the cross-sectional study, 3 groups of children from different departments were enrolled from Feb 6th, 2023 (6th week) to May 28th (21th week), 2023, including influenza-like case group from emergency department for nucleic acid testing of influenza virus (Flu) and human metapneumovirus (HMPV), the outpatient ARI group under nucleic acid testing for Flu, respiratory syncytial virus (RSV), adenovirus (ADV), and parainfluenza virus (PIV), and the inpatient ARI group under nucleic acid testing for Flu, RSV, HMPV, ADV, human bocavirus (HBoV), Rhinovirus (Rh), PIV, coronavirus (HCoV), Mycoplasma pneumoniae (Mp) and Chlamydia pneumonia (Cp). Results: There were 320 influenza-like cases enrolled, including 192 males and 128 females, aged 4.7 (3.6, 6.9) years, and 117 cases (36.6%) positive for Flu A, which contained similar proportion of pandemic H1N1 (H1N1) 47.0% (55/117) and H3N2 53.0% (62/117), and 13 cases for HMPV 4.1% (13/320). The rate of Flu reached its peak at the 10th week, with H1N1 as the predominant one from the 6th to 9th week (10.0%-50.0%) and then H3N2 from the 10th to 16th week (15.0%-90.0%). HMPV was detected from the 15th week 5.0% (1/20), and then reached to 30.0% (6/20) at the 20th week. In the outpatient ARI group, 7 573 were enrolled, including 4 131 males and 3 442 females, aged 4.0 (2.1, 5.3) years, and the highest positive rate for RSV 32.9% (2 491/7 573), followed by Flu A 12.1% (915/7 573). The dominant one was Flu A in weeks 6-14 (23.2%-74.7%), then RSV in the 15th week 24.8% (36/145). In the inpatient ARI group, 1 391 patients were enrolled, including 804 males and 587 females, aged 3.3 (0.4, 5.8) years, and the highest positive rate for Rh 18.7% (260/1 391), followed by RSV 12.4% (173/1 391), Flu A 10.2% (142/1 391, of which 116 cases (81.7%) were H1N1, and 26 cases (18.3%) were H3N2) and HMPV 3.1% (43/1 391). H1N1 was detected from the 7th week 10% (6/60), to peak in the 11th week 31.8% (21/66). H3N2 was detected from the 8th week 1.5% (1/68), and then kept in low level. The proportion of H1N1 among Flu was 81.7% (116/142) in the inpatient ARI group. RSV was detected from 12th week 1.3% (1/80), reaching 30.4% (35/115) at 19th week. The positive rate of HMPV reached 12.1% (14/116) at 21th week. Conclusions: In the spring of 2023, the first one in Beijing is the Flu epidemic, with H1N1 being the predominant one in the early stage and H3N2 in the later stage. Then, there is a postponed RSV epidemic and an increased HMPV detection. In addition, nucleic acid testing for outpatient children should be strengthened to provide early warning of epidemics.

[The role and mechanism of tumor metastasis-associated gene 1 in radiosensitivity of HeLa cells].

Objective: To determine the effect of tumor metastasis-associated gene 1 (MTA1) on the sensitivity of HeLa cells to radiotherapy, and to clarify its molecular mechanism. Methods: The transcriptome differences between MTA1 knocked down Hela cells and control cells were analyzed, and the differentially expressed genes (DEGs) was used to perform Gene-Set Enrichment Analysis (GSEA) and Gene Ontology (GO) cluster analysis. Flow cytometry was used to detect apoptosis in MTA1-overexpressed HeLa cells and control cells before and after 10 Gy X-ray irradiation. Cloning formation assay and real-time cellular analysis (RTCA) were used to monitor the cell proliferation before and after 2 Gy X-ray irradiation. To dissect the underlying molecular mechanisms of MTA1 affecting the sensitivity of radiotherapy, the proteins encoded by the DEGs were selected to construct a protein-protein interaction network, the expression of γ-H2AX was detected by immunofluorescence assay, and the expression levels of γ-H2AX, ß-CHK2, PARP and cleaved caspase 3 were measured by western blot. Results: By transcriptome sequencing analysis, we obtained 649 DEGs, of which 402 genes were up-regulated in MTA1 knockdown HeLa cells and 247 genes were down-regulated. GSEA results showed that DEGs associated with MTA1 were significantly enriched in cellular responses to DNA damage repair processes. The results of flow cytometry showed that the apoptosis rate of MTA1 over-expression group (15.67±0.81)% after 10 Gy X-ray irradiation was significantly lower than that of the control group [(40.27±2.73)%, P<0.001]. After 2 Gy X-ray irradiation, the proliferation capacity of HeLa cells overexpressing MTA1 was higher than that of control cells (P=0.024). The numbers of colon in MTA1 over-expression group before and after 2 Gy X-ray irradiation were (176±7) and (137±7) respectively, higher than (134±4) and (75±4) in control HeLa cells (P<0.05). The results of immunofluorescence assay showed that there was no significant expression of γ-H2AX in MTA1 overexpressed and control HeLa cells without X-ray irradiation. Western blot results showed that the expression level of ß-CHK2 in MTA1-overexpressing HeLa cells (1.04±0.06) was higher than that in control HeLa cells (0.58±0.25, P=0.036) after 10 Gy X-ray irradiation. The expression levels of γ-H2AX, PARP, and cleaved caspase 3 were 0.52±0.13, 0.52±0.22, and 0.63±0.18, respectively, in HeLa cells overexpressing MTA1, which were lower than 0.87±0.06, 0.78±0.12 and 0.90±0.12 in control cells (P>0.05). Conclusions: This study showed that MTA1 is significantly associated with radiosensitivity in cervical cancer HeLa cells. MTA1 over-expression obviously reduces the sensitivity of cervical cancer cells to X-ray irradiation. Mechanism studies initially indicate that MTA1 reduces the radiosensitivity of cervical cancer cells by inhibiting cleaved caspase 3 to suppress apoptosis and increasing ß-CHK2 to promote DNA repair.

[Value of tumor growth rate in evaluating the early therapeutic efficacy of neuroendocrine neoplasm].

Objective: To determinate the value of tumor growth rate (TGR) in evaluating the efficacy of early drug treatment for neuroendocrine neoplasm (NEN). Methods: Patients with NEN who treated at Chinese Academy of Medical Sciences Cancer Hospital from January 2010 to December 2018 were retrospectively enrolled. A total of 30 patients (16 males and 14 females, aged from 26 to 73 (53±11) years) were enrolled. The sum of largest diameter of target lesions and the interval time were measured, TGR of 3 months after the first treatment was calculated using a formula. Intraclass correlation coefficient (ICC) were used to test the repeatability of TGR. Receiver operating characteristic curve (ROC) analysis was used to determine the optimal cut-off values of TGR for predicting progression-free survival (PFS). Overall patients and SD patients assessed by RECIST were grouped by the optimal cut-off values of TGR. Kaplan-Meier method was used to estimate PFS rates and plot patient survival curves of patients at different group of TGR. Cox risk proportional hazard model was used to assess the effect of TGR on the prognosis. Results: The optimal cut-off value of TGR was -5.8(%/m), the area under the curve was 0.921 (95%CI: 0.824-0.999, P<0.001). Interobserver ICC was 0.955 (95%CI: 0.907-0.978,P<0.001). Multivariate Cox analysis showed that compared with the patients with TGR<-5.8, the patients with TGR ≥-5.8 had a higher risk of progression in either overall population (HR: 10.906, 95%CI: 1.953-60.898, P=0.006) or the SD population (HR: 14.354, 95%CI: 1.602-128.627, P=0.017); TGR ≥-5.8 was an independent risk factor affecting the prognosis of NEN. Conclusions: TGR can evaluate the efficacy of NEN's early anti-tumor drug treatment, and associate with prognosis.

[Clinical characteristics of human adenovirus infection in hospitalized children with acute respiratory infection in Beijing].

Objective: To compare the clinical characteristics of different types of human adenovirus (HAdV) infection in hospitalized children with acute respiratory infection in Beijing, and to clarify the clinical necessity of adenovirus typing. Methods: In a cross-sectional study, 9 022 respiratory tract specimens collected from hospitalized children with acute respiratory infection from November 2017 to October 2019 in Affiliated Children's Hospital, Capital Institute of Pediatrics were screened for HAdV by direct immunofluorescence (DFA) and (or) nucleic acid detection. Then the Penton base, Hexon and Fiber gene of HAdV were amplified from HAdV positive specimens to confirm their HAdV types by phylogenetic tree construction. Clinical data such as laboratory results and imaging data were analyzed for children with predominate type HAdV infection using t, U, or χ2 test. Results: There were 392 cases (4.34%) positive for HAdV among 9 022 specimens from hospitalized children with acute respiratory infection. Among those 205 cases who were successfully typed, 131 were male and 74 were female, age of 22.6 (6.7, 52.5) months,102 cases (49.76%) were positive for HAdV-3 and 86 cases (41.95%), HAdV-7, respectively, while 17 cases were confirmed as HAdV-1, 2, 4, 6, 14 or 21. In comparison of clinical characteristics between the predominate HAdV type 7 and 3 infection, significant differences were shown in proportions of children with wheezing (10 cases (11.63%) vs. 25 cases (24.51%)), white blood cell count >15 ×109/L (4 cases (4.65%) vs.14 cases (13.73%)), white blood cell count <5×109/L (26 cases (30.23%) vs.11 cases (10.78%)), procalcitonin level>0.5 mg/L (43 cases (50.00%) vs. 29 cases (28.43%)), multilobar infiltration (45 cases (52.33%) vs.38 cases (37.25%)), pleural effusion (23 cases (26.74%) vs. 10 cases (9.80%)), and severe adenovirus pneumonia (7 cases (8.14%) vs. 2 cases (1.96%)) with χ²=5.11, 4.44, 11.16, 9.19, 4.30, 9.25, 3.91 and P=0.024, 0.035, 0.001, 0.002, 0.038, 0.002, 0.048, respectively, and also in length of hospital stay (11 (8, 15) vs. 7 (5, 13) d, Z=3.73, P<0.001). Conclusions: HAdV-3 and 7 were the predominate types of HAdV infection in hospitalized children with acute respiratory tract infection in Beijing. Compared with HAdV-3 infection, HAdV-7 infection caused more obvious inflammatory reaction, more severe pulmonary symptoms, longer length of hospital stay, suggesting the clinical necessity of further typing of HAdVs.

LncRNA ZEB2-AS1 promotes the proliferation, migration and invasion of esophageal squamous cell carcinoma cell through miR-574-3p/HMGA2 axis.

The article "LncRNA ZEB2-AS1 promotes the proliferation, migration and invasion of esophageal squamous cell carcinoma cell through miR-574-3p/HMGA2 axis, by J.-H. Xu, R.-Z. Chen, L.-Y. Liu, X.-M. Li, C.-P. Wu, Y.-T. Zhou, J.-D. Yan, Z.-Y. Zhang, published in Eur Rev Med Pharmacol Sci 2020; 24 (10): 5391-5403-DOI: 10.26355/eurrev_202005_21323-PMID: 32495874" has been withdrawn from the authors due to some technical reasons. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/21323.

[Investigation of pathogenic agents causing acute respiratory tract infections in pediatric patients in a children's hospital assigned for case screening in Beijing during the outbreak of COVID-19].

Objective: To investigate the spectrum of pathogenic agents in pediatric patients with acute respiratory infections (ARI) during the outbreak of coronavirus infectious diseases 2019 (COVID-19). Methods: Three groups of children were enrolled into the prospective study during January 20 to February 20, 2020 from Capital Institute of Pediatrics, including children in the exposed group with ARI and epidemiological history associated with COVID-19 from whom both pharyngeal and nasopharyngeal swabs were collected, children in the ARI group without COVID-19 associated epidemiological history and children in the screening group for hospital admission, with neither COVID-19 associated epidemiological history nor ARI. Only nasopharyngeal swabs were collected in the ARI group and screening group. Each group is expected to include at least 30 cases. All specimens were tested for 2019-nCoV nucleic acid by two diagnostic kits from different manufacturers. All nasopharyngeal swabs were tested for multiple respiratory pathogens, whilst the results from the ARI group were compared with that in the correspondence periods of 2019 and 2018 used by t or χ(2) test. Results: A total of 244 children were enrolled into three groups, including 139 males and 105 females, the age was (5±4) years. The test of 2019-nCoV nucleic acid were negative in all children, and high positive rates of pathogens were detected in exposed (69.4%, 25/36) and ARI (55.3%, 73/132) groups, with the highest positive rate for mycoplasma pneumoniae (MP) (19.4%, 7/36 and 17.4%, 23/132, respectively), followed by human metapneumovirus (hMPV) (16.7%, 6/36 and 9.8%, 13/132, respectively). The positive rate (11.8%, 9/76) of pathogens in the screening group was low. In the same period of 2019, the positive rate of pathogens was 83.7% (77/92), with the highest rates for respiratory syncytial virus (RSV) A (29.3%, 27/92), followed by influenza virus (Flu) A (H1N1) (19.6%, 18/92) and adenovirus (ADV) (14.1%, 13/92), which showed significant difference with the positive rates of the three viruses in 2020 (RSV A: χ(2)=27.346, P<0.01; FluA (H1N1): χ(2)=28.083, P<0.01; ADV: χ(2)=7.848, P=0.005) . In 2018, the positive rate of pathogens was 61.0% (50/82), with the highest rate for human bocavirus (HBoV) (13.4%, 11/82) and followed by ADV (11.0%, 9/82), and significant difference was shown in the positive rate of HBoV with that in 2020 (χ(2)=6.776, P=0.009). Conclusions: The infection rate of 2019-nCoV is low among children in Beijing with no family clustering or no close contact, even with epidemiological history. The spectrum of pathogens of ARI in children during the research period is quite different from that in the previous years when the viral infections were dominant. MP is the highest positively detected one among the main pathogens during the outbreak of COVID-19 in Beijing where there is no main outbreak area.

LncRNA ZEB2-AS1 promotes the proliferation, migration and invasion of esophageal squamous cell carcinoma cell through miR-574-3p/HMGA2 axis.

OBJECTIVE: Esophageal squamous cell carcinoma (ESCC) is a common malignant epithelial tumor in the elderly, and the cause is very complicated. Therefore, the study of the pathogenesis of ESCC is conducive to the effective treatment of ESCC. Many studies indicated that lncRNAs were important regulatory factors in tumor formation and disease development. However, the regulatory network of lncRNA in ESCC has not been fully explored. MATERIALS AND METHODS: The expression of miR-574-3p, ZEB2-AS1, and HMGA2 was measured using qRT-PCR. The protein expression of PCNA, Cleaved-caspase3, MMP9, and HMGA2 was detected through Western blot. Cell proliferation or apoptosis of transfected cells was calculated via CKK-8 assay or flow cytometry. Transwell assay was applied to detect cell migration and invasion of ESCC cells. Luciferase reporter assay and RNA pull-down were used to determine the relationship among miR-574-3p, ZEB2-AS1, and HMGA2 in ESCC. Moreover, the regulatory network of ZEB2-AS1 has been verified in vivo in this study. RESULTS: We found that ZEB2-AS1 was upregulated in ESCC tissues and cells. The knockdown of ZEB2-AS1 could inhibit cell proliferation, invasion, and migration, as well as promoted cell apoptosis in ESCC. Interestingly, miR-574-3p deficiency or HMGA2 promotion could reverse the effects of si-ZEB2-AS1 on ESCC cell progression. Luciferase reporter assay indicated that miR-574-3p was a target miRNA of ZEB2-AS1 and HMGA2 was a target gene of miR-574-3p in ESCC. CONCLUSIONS: In this paper, we first verified the novel regulatory mechanism of lncRNA ZEB2-AS1 in ESCC cellular process. LncRNA ZEB2-AS1 promoted the proliferation, migration, and invasion of ESCC by modulating miR-574-3p/HMGA2 axis, indicating that ZEB2-AS1 played essential roles in cell progression in ESCC and providing a new therapeutic target of ESCC.

Quantitative analysis of multiple elements in healthy and remodeled epithelium from human upper airway mucosa using nuclear microscopy.

Elements are vital in airway mucosal physiology and pathology, but their distribution and levels in the mucosa remain unclear. This study uses the state-of-the-art nuclear microscopy facility to map and quantify multiple elements in the histology sections of nasal mucosa from patients with nasal polyps or inverted papilloma. Our results demonstrate that P and Ca are the most abundant elements in mucosa and their distinct difference between epithelial and subepithelial regions; more importantly, our results reveal decreased amounts of Cu and Zn in the remodeled epithelium as compared to the normal epithelium. These findings suggest that Cu and Zn may be beneficial targets to regulate aberrant epithelial remodeling in airway inflammation.

Putative role of ischemic postconditioning in a rat model of limb ischemia and reperfusion: involvement of hypoxia-inducible factor-1? expression

Hypoxia-inducible factor-1α (HIF-1α) is one of the most potent angiogenic growth factors. It improves angiogenesis and tissue perfusion in ischemic skeletal muscle. In the present study, we tested the hypothesis that ischemic postconditioning is effective for salvaging ischemic skeletal muscle resulting from limb ischemia-reperfusion injury, and that the mechanism involves expression of HIF-1α. Wistar rats were randomly divided into three groups (n=36 each): sham-operated (group S), hindlimb ischemia-reperfusion (group IR), and ischemic postconditioning (group IPO). Each group was divided into subgroups (n=6) according to reperfusion time: immediate (0 h, T0), 1 h (T1), 3 h (T3), 6 h (T6), 12 h (T12), and 24 h (T24). In the IPO group, three cycles of 30-s reperfusion and 30-s femoral aortic reocclusion were carried out before reperfusion. At all reperfusion times (T0-T24), serum creatine kinase (CK) and lactate dehydrogenase (LDH) activities, as well as interleukin (IL)-6, IL-10, and tumor necrosis factor-α (TNF-α) concentrations, were measured in rats after they were killed. Histological and immunohistochemical methods were used to assess the skeletal muscle damage and HIF-1α expression in skeletal muscle ischemia. In groups IR and IPO, serum LDH and CK activities and TNF-α, IL-6, and IL-10 concentrations were all significantly increased compared to group S, and HIF-1α expression was up-regulated (P<0.05 or P<0.01). In group IPO, serum LDH and CK activities and TNF-α and IL-6 concentrations were significantly decreased, IL-10 concentration was increased, HlF-1α expression was down-regulated (P<0.05 or P<0.01), and the pathological changes were reduced compared to group IR. The present study suggests that ischemic postconditioning can reduce skeletal muscle damage caused by limb ischemia-reperfusion and that its mechanisms may be related to the involvement of HlF-1α in the limb ischemia-reperfusion injury-triggered inflammatory response.

Putative role of ischemic postconditioning in a rat model of limb ischemia and reperfusion: involvement of hypoxia-inducible factor-1α expression.

Hypoxia-inducible factor-1α (HIF-1α) is one of the most potent angiogenic growth factors. It improves angiogenesis and tissue perfusion in ischemic skeletal muscle. In the present study, we tested the hypothesis that ischemic postconditioning is effective for salvaging ischemic skeletal muscle resulting from limb ischemia-reperfusion injury, and that the mechanism involves expression of HIF-1α. Wistar rats were randomly divided into three groups (n=36 each): sham-operated (group S), hindlimb ischemia-reperfusion (group IR), and ischemic postconditioning (group IPO). Each group was divided into subgroups (n=6) according to reperfusion time: immediate (0 h, T0), 1 h (T1), 3 h (T3), 6 h (T6), 12 h (T12), and 24 h (T24). In the IPO group, three cycles of 30-s reperfusion and 30-s femoral aortic reocclusion were carried out before reperfusion. At all reperfusion times (T0-T24), serum creatine kinase (CK) and lactate dehydrogenase (LDH) activities, as well as interleukin (IL)-6, IL-10, and tumor necrosis factor-α (TNF-α) concentrations, were measured in rats after they were killed. Histological and immunohistochemical methods were used to assess the skeletal muscle damage and HIF-1α expression in skeletal muscle ischemia. In groups IR and IPO, serum LDH and CK activities and TNF-α, IL-6, and IL-10 concentrations were all significantly increased compared to group S, and HIF-1α expression was up-regulated (P<0.05 or P<0.01). In group IPO, serum LDH and CK activities and TNF-α and IL-6 concentrations were significantly decreased, IL-10 concentration was increased, HlF-1α expression was down-regulated (P<0.05 or P<0.01), and the pathological changes were reduced compared to group IR. The present study suggests that ischemic postconditioning can reduce skeletal muscle damage caused by limb ischemia-reperfusion and that its mechanisms may be related to the involvement of HlF-1α in the limb ischemia-reperfusion injury-triggered inflammatory response.

Sulforaphane enhances the activity of the Nrf2-ARE pathway and attenuates inflammation in OxyHb-induced rat vascular smooth muscle cells.

AIM: A growing body of evidence indicates that the nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) pathway plays a protective role in many physiological stress processes such as inflammatory damage, oxidative stress, and the accumulation of toxic metabolites, which are all involved in the cerebral vasospasm following subarachnoid hemorrhage (SAH). We hypothesized that the Nrf2-ARE pathway might have a protective role in cerebral vasospasm following SAH. MATERIALS AND METHODS: In our study, we investigate whether the oxyhemoglobin (OxyHb) can induce the activation of the Nrf2-ARE pathway in vascular smooth muscle cells (VSMCs), and evaluate the modulatory effects of sulforaphane (SUL) on OxyHb-induced inflammation in VSMCs. RESULTS: As a result, both the protein level and the mRNA level of the nuclear Nrf2 were significantly increased, while the mRNA levels of two Nrf2-regulated gene products, both heme oxygenase-1 and NAD(P)H: quinone oxidoreductase-1, were also up-regulated in VSMCs induced with OxyHb. A marked increase of inflammatory cytokines such as IL-1ß, IL-6 and TNF-α release was observed at 48 h after cells were treated with OxyHb. SUL enhanced the activity of the Nrf2-ARE pathway and suppressed cytokine release. CONCLUSIONS: Our results indicate that the Nrf2-ARE pathway was activated in OxyHb-induced VSMCs. SUL suppressed cytokine release via the activation of the Nrf2-ARE pathway in OxyHb-induced VSMCs.

BNIP-Salpha induces cell rounding and apoptosis by displacing p50RhoGAP and facilitating RhoA activation via its unique motifs in the BNIP-2 and Cdc42GAP homology domain.

Changes in cell morphology are linked to many cellular events including cytokinesis, differentiation, migration and apoptosis. We recently showed that BNIP-Salpha induced cell rounding that leads to apoptosis via its BNIP-2 and Cdc42GAP Homology (BCH) domain, but the underlying mechanism has not been determined. Here, we have identified a unique region (amino acid 133-177) of the BNIP-Salpha BCH domain that targets RhoA, but not Cdc42 or Rac1 and only the dominant-negative form of RhoA could prevent the resultant cell rounding and apoptotic effect. The RhoA-binding region consists of two parts; one region (residues 133-147) that shows some homology to part of the RhoA switch I region and an adjacent sequence (residues 148-177) that resembles the REM class I RhoA-binding motif. The sequence 133-147 is also necessary for its heterophilic interaction with the BCH domain of the Rho GTPase-activating protein, p50RhoGAP/Cdc42GAP. These overlapping motifs allow tripartite competition such that overexpression of BNIP-Salpha could reduce p50RhoGAP binding to RhoA and restore RhoA activation. Furthermore, BNIP-Salpha mutants lacking the RhoA-binding motif completely failed to induce cell rounding and apoptosis. Therefore, via unique binding motifs within its BCH domain, BNIP-Salpha could interact and activate RhoA while preventing its inhibition by p50RhoGAP. This concerted mechanism could allow effective propagation of the RhoA pathway for cell rounding and apoptosis.

The role of leptin resistance in the lipid abnormalities of aging.

Leptin resistance has been implicated in the pathogenesis of obesity-related complications involving abnormalities of lipid metabolism that resemble those of old age. To determine whether development of leptin resistance in advancing age might account for such abnormalities, we compared the effects of hyperleptinemia (>40 ng/ml) induced in 2-month-old and 18-month-old lean wild-type (+/+) Zucker diabetic fatty rats by adenovirus gene transfer. The decline in food intake, body weight, and body fat in old rats was only 25%, 50%, and 16%, respectively, of the young rats. Whereas in young rats plasma free fatty acids fell 44% and triacylglycerol (TG) 94%, neither changed in the rats. In hyperleptinemic young rats, adipocyte expression of preadipocyte factor 1 increased dramatically and leptin mRNA virtually disappeared; there was increased expression of acyl CoA oxidase, carnitine palmitoyl transferase 1, and their transcription factor peroxisome proliferator-activated receptor alpha, accounting for the reduction in body fat. These hyperleptinemia-induced changes were profoundly reduced in the old rats. On a high-fat diet, old rats consumed 28% more calories than the young and gained 1.5x as much fat, despite greater endogenous hyperleptinemia. Expression of a candidate leptin resistance factor, suppressor of cytokine signaling 3 (SOCS-3), was compared in the hypothalamus and white adipocytes of young and old rats before and after induction of hyperleptinemia; hypothalamic SOCS-3 mRNA was approximately 3x higher in old rats before, whereas it was 3x higher in WAT after, hyperleptinemia. We conclude that the anorexic and antilipopenic actions of leptin decline with age, possibly through increased SOCS-3 expression, and that this could account for the associated abnormalities in lipid metabolism of the elderly.

[The clinical and pathologic study of embeded supernumerary teeth].

OBJECTIVE: To analyse the clinic and pathologic features of 100 embedded supernumerary teeth, to find out the rule of cystic change of supernumerary teeth and its relationship to malocclusion, and to present the methods of therapy. METHODS: Analysis of clinical data, X-ray manifestation,comparison of the findings on operation and pathological changes demonstrated the correct diagnosis of supernumerary teeth. RESULTS: On statistics and analysis,66% of the crowns of the supernumerary teeth were showed different sizes of circular photic shades,but only 35% were proved to be cystic change by biopsies. CONCLUSION: This study showed that 35% had cystic change among 100 cases,so if the diagnosis can be made in these cases with indication of operation the extraction of the supernumerary teeth must be done as soon as possible.

Role of leptin in peroxisome proliferator-activated receptor gamma coactivator-1 expression.

Peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1), a cold-induced protein expressed in brown adipose tissue (BAT), plays a role in adaptive thermogenesis by up-regulating uncoupling proteins (UCP). Here, we explore its relationship to the thermogenic actions of leptin, which also up-regulates UCPs. We find that PGC-1 messenger RNA (mRNA) is markedly reduced in BAT of obese leptin-deficient (ob/ob mice) and leptin-unresponsive (db/db mice and Zucker diabetic fatty fa/fa rats) rodents. Whereas, after cold exposure (6 C for 7 h), PGC-1 mRNA increases 2.6-fold in BAT of lean +/+ rats, it rises only 30% in fa/fa rats. Four days after induction of hyperleptinemia (>30 ng/ml) in Wistar rats, by adenovirus gene transfer, PGC-1 mRNA in BAT was 2.3-fold and UCP-1, 4-fold above controls. In isolated white adipocytes, PGC-1 mRNA increased 4.4-fold within 6 h of incubation with 20 ng/ml of leptin. We conclude that leptin action is required for normal basal and cold-stimulated PGC-1 expression in BAT in rodents and that hyperleptinemia rapidly up-regulates its expression, at least in part, by direct action.

Leptin resistance of adipocytes in obesity: role of suppressors of cytokine signaling.

Liver-derived hyperleptinemia induced in normal rats by adenovirus-induced gene transfer causes rapid disappearance of body fat, whereas the endogenous adipocyte-derived hyperleptinemia of obesity does not. Here we induce liver-derived hyperleptinemia in rats with adipocyte-derived hyperleptinemia of acquired obesity caused by ventromedial hypothalamus lesioning (VMH rats) or by feeding 60% fat (DIO rats). Liver-derived hyperleptinemia in obese rats caused only a 5-7% loss of body weight, compared to a 13% loss in normoleptinemic lean animals; but in actual grams of weight lost there was no significant difference between obese and lean groups, suggesting that a subset of cells remain leptin-sensitive in obesity. mRNA and protein of a putative leptin-resistance factor, suppressor of cytokine signaling (SOCS)-1 or -3, were both increased in white adipose tissues (WAT) of VMH and DIO rats. Since transgenic overexpression of SOCS-3 in islets reduced the lipopenic effect of leptin by 75%, we conclude that the increased expression of SOCS-1 and -3 in WAT of rats with acquired obesity could have blocked leptin's lipopenic action in the leptin-resistant WAT population.

Echocardiographic destruction of albumin microbubbles directs gene delivery to the myocardium.

BACKGROUND: The noninvasive, tissue-specific delivery of therapeutic agents to the heart would be a valuable clinical tool. This study addressed the hypothesis that albumin-coated microbubbles could be used to effectively deliver an adenoviral transgene to rat myocardium by ultrasound-mediated microbubble destruction. METHODS AND RESULTS: Recombinant adenovirus containing beta-galactosidase and driven by a constitutive promoter was attached to the surface of albumin-coated, perfluoropropane-filled microbubbles. These bubbles were infused into the jugular vein of rats with or without simultaneous echocardiography. Additional controls included ultrasound of microbubbles that did not contain virus, virus alone, and virus plus ultrasound. One group underwent ultrasound-mediated destruction of microbubbles followed by adenovirus infusion. Rats were killed after 4 days and examined for beta-galactosidase expression. The hearts of all rats that underwent ultrasound-mediated destruction of microbubbles containing virus showed nuclear staining with 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside substrate, indicating expression of the transgene. None of the control animals showed myocardial expression of the beta-galactosidase transgene. By quantitative analysis, beta-galactosidase activity was 10-fold higher in the treated group than in controls (P<0.0001). CONCLUSIONS: Ultrasound-mediated destruction of albumin-coated microbubbles is a promising method for the delivery of bioactive agents to the heart.

Comparing the hypothalamic and extrahypothalamic actions of endogenous hyperleptinemia.

To determine whether the depletion of body fat caused by adenovirus-induced hyperleptinemia is mediated via the hypothalamus, we used as a "bioassay" for hypothalamic leptin activity the hypothalamic expression of a leptin-regulated peptide, cocaine- and amphetamine-regulated transcript (CART). The validation of this strategy was supported by the demonstration that CART mRNA was profoundly reduced in obese rats with impaired leptin action, whether because of ablation of the ventromedial hypothalamus (VMH) or a loss-of-function mutation in the leptin receptor, as in Zucker diabetic fatty rats. We compared leptin activity in normal rats made hyperleptinemic by adenovirus-leptin treatment (43 +/- 9 ng/ml, cerebrospinal fluid leptin 100 pg/ml) with normal rats made hyperleptinemic by a 60% fat intake (19 +/- 4 ng/ml, cerebrospinal fluid leptin 69 +/- 22 pg/ml). CART was increased 5-fold in the former and 2-fold in the latter, yet in adenovirus-induced hyperleptinemia, body fat had disappeared, whereas in high-fat-fed rats, body fat was abundant. Treatment of the high-fat-fed rats with adenovirus-leptin further increased their hyperleptinemia to 56 +/- 6 ng/ml without changing CART mRNA or food intake, indicating that leptin action on hypothalamus had not been increased. Nevertheless, their body fat declined 36%, suggesting that an extrahypothalamic mechanism was responsible. We conclude that in diet-induced obesity body-fat depletion by leptin requires supraphysiologic plasma concentrations that exceed the leptin-transport capacity across the blood-brain barrier.

Hyperleptinemia depletes fat from denervated fat tissue.

Adenovirus-mediated transfer of the leptin gene causes severe hyperleptinemia with rapid disappearance of visible body fat. To determine if this dramatic lipopenic action is mediated by neurotransmitted signals from the central nervous system, we transplanted the right epididymal fat pad of normal rats to the anterior abdominal wall. Four weeks later, rats were infused with either adenovirus-leptin cDNA (AdCMV-leptin) or adenovirus-beta-galactosidase (AdCMV-beta-gal). Eight days later, plasma leptin averaged 23 +/- 12 ng/ml in the former and 1.2 +/- 0.4 ng/ml in the latter. The fat transplant was intact in all 4 AdCMV-beta-gal-infused rats but had disappeared in all 4 hyperleptinemic rats. Tyrosine hydroxylase staining of the fat pad remnant was negative, excluding regrowth of sympathetic nerves. Thus, the lipopenic action of severe hyperleptinemia on adipocytes is not mediated by neurotransmitters, but must have resulted either from direct action of leptin and/or from leptin-mediated neurohormones.

Regulation of fatty acid homeostasis in cells: novel role of leptin.

It is proposed that an important function of leptin is to confine the storage of triglycerides (TG) to the adipocytes, while limiting TG storage in nonadipocytes, thus protecting them from lipotoxicity. The fact that TG content in nonadipocytes normally remains within a narrow range, while that of adipocytes varies enormously with food intake, is consistent with a system of TG homeostasis in normal nonadipocytes. The facts that when leptin receptors are dysfunctional, TG content in nonadipocytes such as islets can increase 100-fold, and that constitutively expressed ectopic hyperleptinemia depletes TG, suggest that leptin controls the homeostatic system for intracellular TG. The fact that the function and viability of nonadipocytes is compromised when their TG content rises above or falls below the normal range suggests that normal homeostasis of their intracellular TG is critical for optimal function and to prevent lipoapoptosis. Thus far, lipotoxic diabetes of fa/fa Zucker diabetic fatty rats is the only proven lipodegenerative disease, but the possibility of lipotoxic disease of skeletal and/or cardiac muscle may require investigation, as does the possible influence of the intracellular TG content on autoimmune and neoplastic processes.