Locating the source node of diffusion process in cyber-physical networks via minimum observers.

Locating the source node that initiates a diffusion process is an increasingly popular topic that contributes new insights into the maintenance of cyber security, rumor detection in social media, digital surveillance of infectious diseases, etc. Existing studies select the observers randomly or select them heuristically according to the network centrality or community measures. However, there still lacks a method to identify the minimum set of observers for accurately locating the source node of information diffusion in cyber physical networks. Here, we fill this knowledge gap by proposing a greedy optimization algorithm by analyzing the differences of the propagation delay. We use extensive simulations with both synthetic and empirical networks to show that the number of observers can be substantially decreased: Our method only uses a small fraction of nodes (10%-20%) as observers in most networks, whereas the conventional random selection methods have to use 2-3 times more nodes as observers. Interestingly, if a network has a large proportion of low-degree nodes (e.g., karate network), it is necessary to recruit more observers. In particular, the periphery nodes that are only connected with one edge must be observers. Combining our greedy optimization algorithm with the diffusion-back method, the performance of source localization is robust against noise.

Influences of epigallocatechin gallate and citric acid on Escherichia coli O157:H7 toxin gene expression and virulence-associated stress response.

Citric acid and EGCG at their minimum inhibitory concentrations were tested in this study. Logarithmic phase cells of Escherichia coli O157:H7 (ATCC 43895) were exposed to EGCG and citric acid respectively. The results of RT-real time PCR showed that both EGCG and citric acid increased stx2 and oxyR expression and decreased stx1, recA and Q expression. The result of Western blotting for RecA protein further indicated that both EGCG and citric acid decreased RecA production. Both EGCG and citric acid increased the level of intracellular reactive oxygen species and H2 O2 production and decreased superoxide dismutase activity. Therefore, EGCG and citric acid might induce stx2 production by increasing oxidative stress response and inhibit stx1 production by suppressing SOS response. In our study, the differential effects of the two antimicrobials were observed. EGCG reduced ompC and rpoS expression. However, citric acid caused an increase in ompC and rpoS expression. Membrane permeability is associated with toxin release. Citric acid increased the outer membrane permeability of E. coli O157:H7. However, the outer membrane of E. coli O157:H7 remained unaffected by EGCG. SIGNIFICANCE AND IMPACT OF THE STUDY: Shiga toxins are the major virulence factors of Escherichia coli O157:H7. The use of antimicrobials triggering Shiga toxin production is controversial. (-)-epigallocatechin-3-gallate (EGCG) citric acid are often used singly or in combination to prevent micro-organisms in some food products. This study evaluated toxin induction in E. coli O157:H7 in response to EGCG and citric acid and investigated the potential mechanism of action. The findings may contribute to the proper use of EGCG and citric acid as antimicrobials.

Totally minimally invasive two-stage esophagectomy with intrathoracic hand-sewn anastomosis: short-term clinical and oncological outcomes.

Several esophageal resection techniques have been reported in literature. The objective of this study is to assess postoperative and oncological outcomes of two-stage minimally invasive esophagectomy (MIE) in a prone position using thoracoscopic hand-sewn anastomosis. Consecutive patients who underwent two-stage MIE in 2016 performed by the senior author were included. This was compared with the preceding cohort of consecutive patients who underwent two-stage hybrid esophagectomy (HE). The primary outcome was 30-day morbidity and mortality. The secondary outcomes were operation duration, length of stay (LOS), total nodes examined (TNE), number of positive nodes (NPN), and resection margin. Overall, 15 patients underwent MIE and 11 patients underwent HE. Respiratory complications occurred in three (20.0%) patients in the MIE group and in five (45.5%) patients in the HE group (P = 0.218). Cardiac complications occurred in two (18.2%) patients, and two other patients (18.2%) experienced anastomotic leak in the HE group. Mean operative duration was 349 ± 41.6 min in MIE and 309 ± 47.8 min in HE (P = 0.040). Median LOS was 10 days (range: 7-70) in MIE and 13 days (range: 10-116) in HE (P = 0.045). Median TNE was 23 (range: 12-36) in MIE and 20 (range: 14-47) in HE (P = 0.775). Longitudinal margin was involved in one patient (9.1%) in HE and no longitudinal margin was involved in the MIE group. Circumferential resection margin was involved in seven patients (46.7%) in MIE and in four patients (36.4%) in HE (P = 0.391). Two-stage MIE using hand-sewn technique is safe and feasible without compromising surgical and oncological outcomes. A multicenter large trial is recommended to confirm these results.

Annual computed tomography scans do not improve outcomes following esophagectomy for cancer: a 10-year UK experience.

Evidence for the best approach to follow-up patients after esophagectomy for cancer is scant and conflicting, and has led to a wide variety in practice. The aim of this study was to evaluate whether our annual routine computed tomography (aCT) scan program changes outcomes. A retrospective review of 169 patients who underwent esophagectomy for cancer in our unit between 2001 and 2010 was performed. aCT scan was part of follow-up in all patients to 5 years. Minimum follow-up was 37 months. The primary outcome measure was survival. Recurrence was detected in 61 cases (36%). aCT scan diagnosed recurrence in only a minority of cases (17 cases, 28%). In the majority of patients, clinical evidence prompted an unplanned CT scan (uCT; 44 cases, 72%). There was no difference in unadjusted survival between the two groups (hazard ratio = 0.61, 95% confidence interval 0.34-1.08, P = 0.090), nor was one more likely to receive secondary oncological treatment (aCT 41% vs. uCT 44%, P = 1.000). When we adjusted survival patterns for confounding covariates, the uCT cohort showed a protective effect (hazard ratio = 0.54, 95% confidence interval 0.28-0.98, P = 0.042). These data suggest that aCT scans do not influence management or survival after esophagectomy. A consensus follow-up protocol for patients treated for esophageal cancer remains to be established.

[Esthetic analysis of upper lip morphology variation after the cross-arch fixed restoration of maxillary implant-supported prostheses via radiographic methods].

Objective: To measure and analyze upper lip morphology variation before and after the cross-arch fixed restoration of the maxillary implant-supported prostheses using cone- beam CT (CBCT) to provide an esthetic objective reference for maxillary edentulous patients. Methods: There were 32 maxillary edentulous patients selected in the Department of Dental Implantology, The Affiliated Stomatological Hospital of Nanjing Medical University from January 2010 to December 2023. The CBCT data of patients with maxillary full-arch implant-supported fixed prostheses were retrospectively collected before implantation (T0), at the time of radio-guide insertion (T1), and after final repair (T2). The length and thickness of the upper lip were measured and analyzed at each time point, and the correlation between the upper lip contour data and facial esthetic parameters was analyzed. Results: After the final prosthodontic treatment, the length of the upper lip was significantly increased from (21.72±2.84) mm to (24.98±2.93) mm (t=-8.13, P<0.001) compared with that before implant treatment. The widths of the middle and vermilion of the upper lip (Sm-Hm/Ls-UP), were reduced from (13.24±1.41), (12.81±1.67) mm to (11.36±1.67), (10.21±1.69) mm, with significant differences (t=7.79, P<0001; t=9.37, P<0.001). The lower face height (Sn-Gn) was increased from (54.52±4.95) mm to (58.70±4.42) mm, with significant differences (t=-11.05, P<0.001). However, the nasolabial angle reduced significantly from 95.35°± 7.70°to 90.53°±7.28°(t=7.68, P<0.001). The width of the middle of the upper lip with a radiation guide was (10.94±1.24) mm, and it increased significantly compared with that after the final prosthesis treatment (t=-0.76, P<0.05). The proportion of straight upper lip profiles accounted for 59% (19/32), and the proportion of concave upper lip profiles accounted for 41% (13/32) after the final prosthesis treatment. In addition, the results of correlation analysis showed that the nasolabial angle variation was weak and negatively correlated with residual bone height (r=-0.37, P=0.490). Conclusions: After the treatment of the maxillary full-arch implant-supported fixed prosthesis, the length of the upper lip increases, and the thickness of the upper lip becomes significantly thin. The maxillary full-arch implant-supported fixed prostheses support upper lips to improve the patients' side appearances.

Prevention of graft versus host disease by inactivation of host antigen-presenting cells.

Graft versus host disease, an alloimmune attack on host tissues mounted by donor T cells, is the most important toxicity of allogeneic bone marrow transplantation. The mechanism by which allogeneic T cells are initially stimulated is unknown. In a murine allogeneic bone marrow transplantation model it was found that, despite the presence of numerous donor antigen-presenting cells, only host-derived antigen-presenting cells initiated graft versus host disease. Thus, strategies for preventing graft versus host disease could be developed that are based on inactivating host antigen-presenting cells. Such strategies could expand the safety and application of allogeneic bone marrow transplantation in treatment of common genetic and neoplastic diseases.

Antitumor activity of the rapamycin analog CCI-779 in human primitive neuroectodermal tumor/medulloblastoma models as single agent and in combination chemotherapy.

We examined the cytotoxicity of the immunosuppressant agent rapamycin and its analogue CCI-779 in human brain tumor cell lines in vitro and in vivo as single agents and in combination with standard chemotherapeutic drugs. In the rapamycin-sensitive PNET/MB cell line DAOY, rapamycin exhibited additive cytotoxicity with cisplatin and with camptothecin. In vivo, CCI-779 delayed DAOY xenograft growth by 160% after 1 week and 240% after 2 weeks of systemic treatment, compared with controls. Single high-dose treatment induced 37% regression of tumor solume. Growth inhibition of DAOY xenografts was 1.3 times greater after simultaneous treatment with CCI-779 and cisplatin than after cisplatin alone. Interestingly, CCI-779 also produced growth inhibition of xenografts derived from U251 malignant glioma cells, a human cell line resistant to rapamycin in vitro. These studies suggest that the rapamycin analogue CCI-779 is an important new agent to investigate in the treatment of human brain tumors, particularly PNET/MB.

Antitumor activity of a human cytotoxic T-cell line (TALL-104) in brain tumor xenografts.

Malignant glioma in adults and primitive neuroectodermal tumors/medulloblastomas in children are the most common malignant primary brain tumors that either respond poorly to current treatment or tend to recur. Adoptive therapy with TALL-104 cells-an IL-2-dependent, major histocompatibility complex nonrestricted, cytotoxic T-cell line-has demonstrated significant antitumor activity against a broad range of implanted or spontaneously arising tumors. This study investigates distribution of systemically and locally administered TALL-104 cells and their efficacy in effecting survival of a rat model of human brain tumor. In vitro, TALL-104 cells showed significant cytotoxic activity when added to human glioblastoma cell lines U-87 MG, U-251 MG, and A1690; the medulloblastoma cell lines DAOY, D283 Med, and D341 Med; and the epidermoid cancer cell line A431. In brain tumor-bearing rats, the amount of fluorescent dye-labeled TALL-104 cells in brain increased after they were given by intracarotid injection as compared with i.v. cell administration. However, TALL-104 cells rapidly decreased to low levels within 1 h after intracarotid injection. This finding suggests that TALL-104 cells given systemically may not invade brain or tumor tissues, but rather may remain in the vascular system, making this approach less efficient for brain tumor treatment. In a model of athymic rats engrafted with human A431 carcinoma brain tumor, repetitive local administration of TALL-104 cells directly into the tumor bed resulted in a significant increase in survival time compared with control animals. Therefore, local therapy with TALL-104 cells may be a novel and highly effective treatment approach for malignant brain tumors.

Decreased cyclin B1 expression contributes to G2 delay in human brain tumor cells after treatment with camptothecin.

DNA damage produces delayed mitosis (G2/M delay) in proliferating cells, and shortening the delay sensitizes human malignant glioma and medulloblastoma cells to cytotoxic chemotherapy. Although activation of the cyclin-dependent kinase CDC2 mediates G2/M transition in all tumor cells studied to date, regulation of CDC2 varies between tumor types. Persistent hyperphosphorylation of kinase and reduced cyclin expression have been implicated as mediators of treatment-induced G2 delay in different tumor models. To evaluate regulation of G2/M transition in human brain tumors, we studied the expression and/or activity of CDC2 kinase and cyclins A and B1 in U-251 MG and DAOY medulloblastoma cells after their treatment with camptothecin (CPT). Synchronized cells were treated during S phase, then harvested at predetermined intervals for evaluation of cell cycle kinetics, kinase activity mRNA, and protein expression. CPT produced G2 delay associated with decreased CDC2 kinase activity and cyclin B1 expression. Kinase activity was associated with CDC2 bound to cyclin B1, not cyclin A, in both cell lines. Cyclin A mRNA and protein expression were reduced after CPT treatment; however, decreased protein expression was short lived and moderate in the glioma and primitive neuroectodermal tumor/medulloblastoma cells, respectively. We conclude that G2 delay is a common response of brain tumor cells to chemotherapy with topoisomerase I inhibitors and that a mechanism of this delay may be reduced expression of cyclin B1.

Influence of airway inflammatory changes on airway hyperresponsiveness in asthmatics.

The effect of changes of airway inflammation on airway nonspecific reactivity were studied in 29 patients with chronic asthma. Detailed examinations of bronchial lavage (BAL) fluid and airway responses to histamine, propranolol and exercise were performed before and after treatment. The patients treated with steroids had significant improvements in parameters of BAL fluid cells and mediators with consistent changes of decreasing airway reactivities to propranolol and exercise after treatment. Whereas no significant changes occurred in the patients treated with B2-agonist either in inflammatory parameters or airway responses. On the other hand, airway response to histamine changed little in all asthmatic patients. Our study implied that inhibiting the airway inflammation in asthmatics may lead to marked decrease of airway response to non-mediator stimuli but fail to attenuate bronchial hyperresponse to mediator stimuli like histamine.

Age-related changes in anatomic bases for the insertion of zygomatic implants.

The objectives of this study were to verify whether Chinese patients are well-suited for zygomatic implantation and to observe age-related changes in the linear and angular anatomic bases of the maxilla and zygoma. Using three-dimensional images selected from maxillofacial cone beam computed tomography (CBCT) scans generated by SimPlant, linear and angular measurements were obtained by simulating zygomatic implantation. The edentulous group comprised 40 subjects aged between 62 and 65 years. A total of 120 dentate cases were divided into three groups based on age: the established occlusion group (n=40; 12-15 years old), the adult group (n=40; 37-40 years old), and the elderly group (n=40; 62-65 years old). The mean potential insertion length of the ordinary and additional zygomatic implants became longer with age in the dentate groups. For both zygomatic implant insertion areas, the anteroposterior lengths of the maxilla and zygoma were thicker in the older dentate groups (P<0.05). Significant differences were verified in the installation direction among the dentate groups. Gender was not a significant factor. The zygomatic skeleton changes with age, which results in linear and angular variations in the zygomatic implant insertion area. Therefore, the anatomic bases in Chinese adults are suitable for zygomatic implants.

When a groin lump is more than a simple groin lump.

Groin lump secondary to avulsion fracture of the adductor muscles of the middle thigh in the absence of any hernia is rare. The authors discuss a case of a young footballer who presented with a painful groin swelling. Surgical exploration revealed that the cause of the lump was an avulsion fracture of the adductor muscles.

Varicose veins: loss of release of vascular endothelial growth factor and reduced plasma nitric oxide.

OBJECTIVES: To examine the release of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in primary varicose veins (VVs) and normal vein controls following experimentally-induced venous stasis. DESIGN, MATERIALS AND METHODS: Patients with primary VVs (n=21) and control subjects (n=11) were rested supine for 15 min. Blood was collected from both an arm and foot vein. A below-knee cuff was applied and inflated to 90-95 mmHg for 10 min (to prompt venous stasis). Further blood samples were collected from the foot vein. Levels of plasma VEGF and NO were analysed. RESULTS: In control subjects, application of the cuff increased levels of plasma VEGF in the foot (p<0.025). In contrast, in patients with VVs, there was little or no change in these levels of plasma VEGF. Cuff application had little effect on levels of plasma NO in either controls, or those with VVs. When compared to controls however, the levels of plasma NO in all samples with VVs (arm, or foot before, or after, cuff application) were reduced (all, p<0.05). CONCLUSIONS: Loss of VEGF release with experimentally-induced venous stasis, and reduced levels of plasma NO may suggest a mechanism important in the development of primary VVs.

[An epidemiological study on the relationship between musculoskeletal disorders and work load]. / Atiologische Feldstudie zur Beziehung zwischen Wirbelsäulenerkrankung und Arbeitsbelastung.

965 workers engaged in working tasks of work intensity grade 2, 3, 4 (based on Chinese National Standard) were investigated on the musculoskeletal disorders with a questionnaire. The lumbar vertebra of 136 randomly chosen workers were also radiologically examined. The result revealed that the prevalence of low-back disorders was 51.2% on average and it was obviously correlated with such factors as age, standing, previous back injury, education level, sport activity, work intensity, working posture, satisfaction with the tools as well as work condition and house work. Heavy work load and unneutral working posture were proved to be the main factors as revealed by the multifactor analysis and further supported by the findings of X-ray examination.